In JoVE (1)

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Articles by Joseph M. Wider in JoVE

Other articles by Joseph M. Wider on PubMed

The Complete Amino Acid Sequence of Porcine Gastrotropin, an Ileal Protein Which Stimulates Gastric Acid and Pepsinogen Secretion

The Journal of Biological Chemistry. Oct, 1988  |  Pubmed ID: 3049572

The stomach is stimulated by an enterooxyntin factor in a delayed response to feeding, resulting in an increase in both gastric acid and pepsinogen secretion. We have previously reported on the identity of such a factor from the porcine ileum (Wider, M. D., Vinik, A. I., and Heldsinger, A. (1984) Endocrinology 115, 1484-1491). This protein, termed gastrotropin, is localized to the distal region of the ileum where it constitutes less than 0.1% of the cytosolic protein. We have completed the primary structure of porcine gastrotropin by Edman degradation and mass spectrometry. Gastrotropin (Mr = 14,054) contains 127 amino acid residues and has a blocked (acetylated) alanine at its NH2 terminus. The sequence of porcine gastrotropin is similar to rat liver fatty acid-binding protein (FABP), with 44 of 127 residues being identical (35%). Homology with other members of the FABP family is significantly less apparent, with the order of similarity being liver FABP greater than heart FABP greater than retinol-binding protein greater than intestine FABP. The sequences of the NH2-terminal regions of these proteins account for virtually all of the homology; there are 9 conserved residues common to all five proteins. Gastrotropin represents the first member of the FABP family which has an extracellular function.

Isolation and Partial Characterization of Gastrotropin from Canine Ileum: Further Studies of the Parietal and Chief Cell Response

Endocrinology. Nov, 1988  |  Pubmed ID: 3168934

Gastrotropin (GT), a protein previously isolated from porcine ileal mucosa, with a molecular mass of 14,054 daltons, was extracted from canine ileum and purified to homogeneity. The canine and porcine peptides had similar relative molecular mass, charge, hydrophobicity, and amino acid compositions. Direct Edman degradation yielded no free amino acids, indicating a blocked NH2-terminus, and a partial sequence determination of the CNBr fragments demonstrated a high degree of homology with porcine GT. Previous studies have indicated that GT is a potent enterooxyntin, and to further characterize these observations we have investigated the actions of both porcine and canine GT on isolated enriched preparations of guinea pig and dog parietal and chief cells. The results of these studies demonstrate that GT is present in more than one species and that the cellular response to porcine and canine GT is identical. The efficacies of canine and porcine GT preparations in stimulating pepsinogen secretion and [14C]aminopyrine uptake were identical and equal to those of cholecystokinin octapeptide (CCK8) and pentagastrin. GT was 100-fold more potent than either of these two major secretagogues. Maximal [14C]aminopyrine accumulation was observed with 10(-8) M GT, with an ED50 of 2 x 10(-9) M compared to pentagastrin, which caused maximal accumulation at 10(-6) M and had an ED50 of 5 x 10(-8) M. Maximal pepsinogen secretion was observed with 10(-7) M GT, with an ED50 of 10(-10) M, compared to 10(-6) M for CCK8, with an ED50 of 10(-8) M. The maximal chief cell response to GT was unaffected by the addition of CCK8 or carbachol, but responded additively with forskolin, indicating that GT uses the same transduction mechanism as CCK8 and carbachol and does not involve the activation of adenylate cyclase. The ED50 values observed with both parietal and chief cells in these studies were close to the basal circulating levels of GT (3.5 x 10(-9) M) in adult pigs. These results clearly demonstrate that GT is a potent component of the enterooxyntin factor identified in studies of the role of the small bowel in the regulation of gastric secretion.

Sequence-specific 1H NMR Assignments and Determination of the Secondary Structure for the Activation Domain Isolated from Pancreatic Procarboxypeptidase B

Biochemistry. Aug, 1990  |  Pubmed ID: 2223783

Nearly complete sequence-specific 1H NMR assignments are presented for amino acid residues 3-81 in the 81-residue globular activation domain of porcine pancreatic procarboxypeptidase B isolated after limited tryptic proteolysis of the zymogen. These resonance assignments are consistent with the chemically determined amino acid sequence. Regular secondary structure elements were identified from nuclear Overhauser effects and the sequence locations of slowly exchanging backbone amide protons. The molecule contains two alpha-helices, including residues 20-30 and approximately residues 58-72, and a three-stranded antiparallel beta-sheet with the individual strands extending approximately from 12 to 17, 50 to 55, and 75 to 77. The identification of these secondary structures and a preliminary analysis of additional long-range NOE distance constraints show that isolated activation domain B forms a stable structure with the typical traits of a globular protein. The data presented here are the basis for the determination of the complete three-dimensional structure of activation domain B, which is currently in progress.

Protein Secondary Structure Determination by NMR. Application with Recombinant Human Cyclophilin

FEBS Letters. Jul, 1991  |  Pubmed ID: 1855591

It is a unique trait of the NMR method for protein structure determination that a description of the polypeptide secondary structure can be obtained at an early stage and quite independently of the complete structure calculation. In this paper the procedures used for secondary structure determination are reviewed and placed in perspective relative to the other steps in a complete three-dimensional structure determination. As an illustration the identification of the regular secondary structure elements in human cyclophilin is described.

Structure of Human Cyclophilin and Its Binding Site for Cyclosporin A Determined by X-ray Crystallography and NMR Spectroscopy

Nature. Sep, 1991  |  Pubmed ID: 1896075

The protein cyclophilin is the major intracellular receptor for the immunosuppressive drug cyclosporin A. Cyclosporin A acts as an inhibitor of T-cell activation and can prevent graft rejection in organ and bone marrow transplantation. Cyclophilin may be responsible for mediating this immunosuppressive response. Cyclophilin also catalyses the interconversion of the cis and trans isomers of the peptidyl-prolyl amide bonds of peptide and protein substrates. Here we report the X-ray crystal structure of human recombinant cyclophilin complexed with a tetrapeptide and the identification, by nuclear magnetic resonance spectroscopy, of the specific binding site for cyclosporin A. Cyclophilin has an eight-stranded antiparallel beta-barrel structure. The prolyl isomerase substrate-binding site is coincident with the cyclosporine-binding site. These results may help to provide a structural basis for rationalizing the immunosuppressive function of the cyclosporin-cyclophilin system and will also be important in the design of improved immunosuppressant drugs.

Skin Closure with Dye-enhanced Laser Welding and Fibrinogen

Plastic and Reconstructive Surgery. Dec, 1991  |  Pubmed ID: 1946752

The topical application of wavelength-specific dye and fibrinogen has been used to enhance laser closure of vascular anastomoses. We compared the closure of skin incisions by two different dye-enhanced, fibrinogen-based laser welding systems [argon laser (power density 4.78 W/cm2) with fluorescein isothiocyanate dye (n = 32) and diode laser (power density 9.55 W/cm2) with indocyanine green dye (n = 32)] with closure by interrupted 5-0 nylon suture (n = 64) and examined tensile strength, hydroxyproline production, histology, and cosmesis. Two 3-cm full-thickness incisions were made on the shaved backs of 64 rats. One incision was closed with suture, whereas the other, after treatment with the appropriate dye, was welded with either argon- or diode-lasered fibrinogen. At postoperative days 5, 10, 15, and 28, the closure sites were harvested and sectioned for analysis. Initially, wounds closed with argon-lasered fibrinogen showed less inflammatory response, greater collagen production (34.61 +/- 0.74 mg/gm), and greater mean peak stress at rupture (64.85 lbs/in2) than those closed with suture (16.42 +/- 3.20 mg/gm, 26.68 lbs/in2) (p less than 0.05). By 15 days, both argon and diode laser closures are superior in strength and collagen production to suture closure (p less than 0.05). At 28 days, diode laser closures (1315.60 lbs/in2) are stronger than suture closures (998.09 lbs/in2), whereas both are stronger than argon laser closures (813.16 lbs/in2) (p less than 0.05). Cosmetically, argon-welded wounds consistently appeared finer and lacked cross-hatched suture scars.(ABSTRACT TRUNCATED AT 250 WORDS)

Receptor-induced Conformation Change of the Immunosuppressant Cyclosporin A

Science (New York, N.Y.). Nov, 1991  |  Pubmed ID: 1948082

The NMR Structure of the Activation Domain Isolated from Porcine Procarboxypeptidase B

The EMBO Journal. Jan, 1991  |  Pubmed ID: 1989879

The three-dimensional structure of the activation domain isolated from porcine pancreatic procarboxypeptidase B was determined using 1H NMR spectroscopy. A group of 20 conformers is used to describe the solution structure of this 81 residue polypeptide chain, which has a well-defined backbone fold from residues 11-76 with an average root mean square distance for the backbone atoms of 1.0 +/- 0.1 A relative to the mean of the 20 conformers. The molecular architecture contains a four-stranded beta-sheet with the polypeptide segments 11-17, 36-39, 50-56 and 75-76, two well defined alpha-helices from residues 20-30 and 60-70, and a 3(10) helix from residues 43-46. The three helices are oriented almost exactly antiparallel to each other, are all on the same side of the beta-sheet, and the helix axes from an angle of approximately 45 degrees relative to the direction of the beta-strands. Three segments linking beta-strands and helical secondary structures, with residues 32-35, 39-43 and 56-61, are significantly less well ordered than the rest of the molecule. In the three-dimensional structure two of these loops (residues 32-35 and 56-61) are located close to each other near the protein surface, forming a continuous region of increased mobility, and the third disordered loop is separated from this region only by the peripheral beta-strand 36-39 and precedes the short 3(10) helix.

The NMR Structure of Cyclosporin A Bound to Cyclophilin in Aqueous Solution

Biochemistry. Jul, 1991  |  Pubmed ID: 2054355

Cyclosporin A bound to the presumed receptor protein cyclophilin was studied in aqueous solution at pH 6.0 by nuclear magnetic resonance spectroscopy using uniform 15N- or 13C-labeling of cyclosporin A and heteronuclear spectral editing techniques. Sequence-specific assignments were obtained for all but one of the cyclosporin A proton resonances. With an input of 108 intramolecular NOEs and four vicinal 3JHN alpha coupling constants, the three-dimensional structure of cyclosporin A bound to cyclophilin was calculated with the distance geometry program DISMAN, and the structures resulting from 181 converged calculations were energy refined with the program FANTOM. A group of 120 conformers was selected on the basis of the residual constraint violations and energy criteria to represent the solution structure. The average of the pairwise root-mean-square distances calculated for the backbone atoms of the 120 structures was 0.58 A. The structure represents a novel conformation of cyclosporin A, for which the backbone conformation is significantly different from the previously reported structures in single crystals and in chloroform solution. The structure has all peptide bonds in the trans form, contains no elements of regular secondary structure and no intramolecular hydrogen bonds, and exposes nearly all polar groups to its environment. The root-mean-square distance between the backbone atoms of the crystal structure of cyclosporin A and the mean of the 120 conformers representing the NMR structure of cyclosporin A bound to cyclophilin is 2.5 A.

Comparison of the NMR Solution Structure with the X-ray Crystal Structure of the Activation Domain from Procarboxypeptidase B

Journal of Biomolecular NMR. Jan, 1992  |  Pubmed ID: 1422143

The NMR solution structure of the activation domain isolated from porcine procarboxypeptidase B is compared with the X-ray crystal structure of the corresponding segment in the intact proenzyme. For the region of the polypeptide chain that has a well-defined three-dimensional structure in solution, i.e., the backbone atoms of residues 11-76 and 25 amino acid side chains in this segment that form a hydrophobic core in the activation domain, the root-mean-square distance between the two structures is 1.1.A. There are no significant differences in average atom positions between the two structures, but only the NMR structure shows increased structural disorder in three outlying loops located along the same edge of the activation domain. These regions of increased structural disorder in the free domain coincide only partially with the interface to the enzyme domain in the proenzyme.

Pancreatic Procarboxypeptidases: Their Activation Processes Related to the Structural Features of the Zymogens and Activation Segments

Biological Chemistry Hoppe-Seyler. Jul, 1992  |  Pubmed ID: 1515065

The molecular events leading to the complete activation of pancreatic procarboxypeptidases A and B have been investigated. For both proteins the activation process follows a similar general scheme: trypsin is responsible for the first cleavage that separates the active enzyme from the activation segment, the degradation of the activation segment proceeds only from its C-terminal end, and activity release can be correlated with the disappearance of the long forms of the activation segment. In both systems, trypsin and the released carboxypeptidase participate in the trimming of the severed activation regions. However, the rate of enzymatic activation is much faster in the case of procarboxypeptidase B. This phenomenon may be explained by some structural differences in the connecting region which acts as a linker between the globular domain of the activation segment and the N-terminal end of carboxypeptidases and also by the higher efficiency of carboxypeptidase B for the digestion of its own activation segment. It is not due to unfolding of the activation domain, since the isolated activation domain retains its globular conformation in solution.

NMR Determination of Residual Structure in a Urea-denatured Protein, the 434-repressor

Science (New York, N.Y.). Sep, 1992  |  Pubmed ID: 1523410

A nuclear magnetic resonance (NMR) structure determination is reported for the polypeptide chain of a globular protein in strongly denaturing solution. Nuclear Overhauser effect (NOE) measurements with a 7 molar urea solution of the amino-terminal 63-residue domain of the 434-repressor and distance geometry calculations showed that the polypeptide segment 54 to 59 forms a hydrophobic cluster containing the side chains of Val54, Val56, Trp58, and Leu59. This residual structure in the urea-unfolded protein is related to the corresponding region of the native, folded protein by simple rearrangements of the residues 58 to 60. Based on these observations a model for the early phase of refolding of the 434-repressor(1-63) is proposed.

Cyclosporin A-cyclophilin Complex Formation. A Model Based on X-ray and NMR Data

FEBS Letters. Apr, 1992  |  Pubmed ID: 1555658

The previously determined 3D NMR solution structure of cyclophilin-bound cyclosporin A (CsA) was docked onto the X-ray crystal structure of cyclophilin. Intermolecular nuclear Overhauser effects (NOE) between CsA and cyclophilin were used as constraints in a restrained energy minimization to generate a model of the complex which satisfied all the NOE distance constraints. The model shows that the residues 9 to 11 and 1 to 5 of the cyclic CsA molecule are in contact with cyclophilin. Comparing the model of the CsA-cyclophilin complex to the X-ray crystal structure of a complex of cyclophilin with a substrate for peptidyl-proline cis-trans isomerase activity, i.e. the linear tetrapeptide substrate ac-Ala-Ala-Pro-Ala-amc (ac, acetyl; amc, amidomethylcoumarin), one notices that the contacting peptide segments in the two ligands are oriented in opposite directions, and that the side chain of MeVal-11 of CsA superposes rather precisely with the position of the prolyl residue in ac-Ala-Ala-Pro-Ala-amc.

Complete 15N and 1H NMR Assignments for the Amino-terminal Domain of the Phage 434 Repressor in the Urea-unfolded Form

Proceedings of the National Academy of Sciences of the United States of America. May, 1992  |  Pubmed ID: 1584772

The amino-terminal domain of the phage 434 repressor consisting of residues 1-69 forms a globular structure of five tightly packed helices, with nearly identical molecular architectures in crystals and in solution. Upon addition of urea to an aqueous solution of this protein, the NMR spectrum of a second form of the protein appears in addition to the native form, and at a urea concentration of 7 M, this urea-unfolded form is the only species observed. At intermediate urea concentrations, the two forms of the protein inter-convert at a rate that allows the observation of the exchange process by NMR. Starting from the previous assignments for the native protein, we obtained nearly complete sequence-specific (1)H and (15)N NMR assignments for the unfolded form of the protein. For most amino acid residues, the (1)H chemical shifts of the urea-unfolded protein are very similar to the random coil values, but some discrete regions of the polypeptide chain were identified that are likely to retain residual nonrandom spatial structure as evidenced by deviations of (1)H chemical shifts and amide proton exchange rates from the expected random coil values.

1H, 15N and 13C NMR Assignments of the 434 Repressor Fragments 1-63 and 44-63 Unfolded in 7 M Urea

FEBS Letters. Jun, 1992  |  Pubmed ID: 1607010

An E. coli overexpression system for the N-terminal domain of the 434 repressor with residues 1-63 (434 repressor(1-63)) was constructed and used to produce this polypeptide with uniform 15N-labeling, and with 13C-labeling of the methyl groups of valine and leucine. Using these protein preparations almost complete sequence-specific resonance assignments were obtained for the urea-unfolded form of the 434 repressor(1-63). In addition, the isotope-labeled tryptic peptide, 44-63, was produced by enzymatic cleavage of the recombinant 434 repressor(1-63), and its NMR spectrum was assigned. Corresponding residues in 434 repressor(1-63) and 434 repressor(44-63) in 7 M urea were found to have nearly identical chemical shifts, and in both species similar deviations from 1H random coil shifts were found as previously in 434 repressor(1-69). These indicate the presence of residual non-random structure in the polypeptide segment 50-60. The present NMR assignments, which include stereospecific assignments for the diastereotopic methyl groups of Val and Leu, are the basis for detailed studies of this residual structure in the urea-unfolded form of the 434 repressor.

The Effect of Fibrin Glue on Skin Grafts in Infected Sites

Plastic and Reconstructive Surgery. Feb, 1992  |  Pubmed ID: 1732894

Fibrin bonding of skin grafts to wounds is an essential part of the graft-adherence process. Bacteria, in concentrations greater than 10(5)/gm of tissue, are associated with graft failure. Sixty-five rats were randomly divided into three groups, dorsal split-thickness skin grafts were harvested, and the sites were inoculated with Staphylococcus aureus. After incubation, each wound was quantitatively biopsied and treated with saline, fibrin glue with aprotinin, or fibrin glue alone. We found that the addition of commercially available fibrin glue with or without the antifibrinolytic agent aprotinin is capable of restoring graft adherence to normal levels in graft sites infected with greater than 10(5) bacteria/gm of tissue. Fibrin glue may have potential for increasing skin-graft take in the clinical situation where the graft bed is infected.

3D 13C-15N-heteronuclear Two-spin Coherence Spectroscopy for Polypeptide Backbone Assignments in 13C-15N-double-labeled Proteins

Journal of Biomolecular NMR. Jan, 1993  |  Pubmed ID: 8448432

The pulse sequence of a new constant-time 3D triple-resonance experiment, ct-HA[CAN]HN, is presented. This experiment delineates exclusively scalar connectivities and uses 13C alpha-15N heteronuclear two-spin coherence to overlay the chemical shift evolution periods of the 13C alpha and 15N nuclei, thereby providing the four resonance frequencies of the alpha-proton, the alpha-carbon, the amide nitrogen, and the amide proton of a given amino acid residue in three dimensions. This experiment promises to be a valid alternative to 4D experiments, providing the same information on intraresidue polypeptide backbone connectivities in 13C-15N-double-labeled proteins.

The Inhibition of Fibroblast-populated Collagen Lattice Contraction by Human Amniotic Fluid: a Chronologic Examination

Plastic and Reconstructive Surgery. Jun, 1993  |  Pubmed ID: 8497529

The effect of human amniotic fluid on fetal wound healing remains to be fully elucidated and may lead to the isolation of factors that could modulate adult wound healing. This study uses an in vitro model of wound contraction, the fibroblast-populated collagen lattice, to examine the effects of chronologically sampled human amniotic fluid on contraction of lattices composed of either human adult or fetal fibroblasts. This chronology has not been reported previously. Human amniotic fluid was obtained in a sterile fashion via amniocentesis from 120 different women at different time points in gestation, ranging from 13 to 24 weeks. At each time point of gestation, three to five samples were individually examined in duplicate sets. Only fluid from pregnancies deemed normal by amniocentesis was included. Contaminated specimens were discarded. Using Bell's protocol, lattices were constructed of acid-soluble rat tail collagen, growth medium, and either human adult fibroblasts or human fetal fibroblasts. Lattices contained 20% v/v human amniotic fluid. In the control lattices, phosphate-buffered saline replaced amniotic fluid in equal volumes. Area was measured at 24-hour intervals, and all tests were run in duplicate for each specimen. The mean area at each interval was computed for each gestational week examined. Data were analyzed for significance with ANOVA and Dunnett's t test against control.(ABSTRACT TRUNCATED AT 250 WORDS)

Determination of the NMR Solution Structure of the Cyclophilin A-cyclosporin A Complex

Journal of Biomolecular NMR. Jul, 1994  |  Pubmed ID: 8075536

The three-dimensional NMR solution structure of the cyclophilin A (Cyp)-cyclosporin A (CsA) complex was determined, and here we provide a detailed description of the analysis of the NMR data and the structure calculation. Using 15N- and 13C-resolved three- and four-dimensional [1H,1H]-nuclear Overhauser enhancement (NOE) spectroscopy with uniformly isotope-labeled Cyp in the complex, a final data set of 1810 intra-Cyp, 107 intra-CsA and 63 intermolecular NOE upper distance constraints was collected as input for the structure calculation with the program DIANA. A group of DIANA conformers, selected by a previously described analysis of the dependence of the maximal root-mean-square deviation (rmsd) among the individual conformers on the residual target function value, was subjected to energy refinement with the program FANTOM. The 22 best energy-refined conformers were then used to represent the solution structure. The average rmsd relative to the mean structure of these 22 conformers is 1.1 A for the backbone atoms of all residues of the complex. The molecular architecture of Cyp in the Cyp-CsA complex includes an eight-stranded antiparallel beta-barrel, which is closed on each side by an amphipathic helix. CsA is bound in a cavity formed by part of the barrel surface and four loops with nonregular secondary structure. Comparison of this structure with structures of Cyp-CsA and other Cyp-peptide complexes determined by different approaches shows extensive similarities.

Platelets and Lipoproteins

Platelets. 1994  |  Pubmed ID: 21043643

Salt-stabilized Globular Protein Structure in 7 M Aqueous Urea Solution

FEBS Letters. Sep, 1995  |  Pubmed ID: 7556686

A 7 M aqueous urea solution of the 63-residue N-terminal domain of the 434-repressor at pH 7.5 and 18 degrees C contains a mixture of about 10% native, folded protein and 90% unfolded protein. Interconversion between the two conformations is slow on the NMR chemical shift time scale, so that observation of separate resonances can be used to monitor the equilibrium between folded and unfolded protein when changing the solution conditions. In this paper we describe the influence of various salts or non-ionic compounds on this conformational equilibrium. Solution conditions are described which contain a homogenous preparation of the folded protein in the presence of 6 to 7 M urea, providing a basis for an NMR structure determination in concentrated urea and for studies of the solvation of the folded protein in mixed water/urea/salt environments.

Frey's Syndrome: Prevention with Temporoparietal Fascial Flap Interposition

Annals of Plastic Surgery. Mar, 1995  |  Pubmed ID: 7598387

The recent trend in management of Frey's syndrome has been the use of prophylactic procedures performed at the time of parotidectomy to prevent its symptoms postoperatively. An additional benefit of this approach is the prevention of the typical cheek contour deformity after parotidectomy. We reviewed our experience with interposition of a vascularized temporoparietal fascial flap between the parotid bed and overlying skin immediately after complete superficial parotidectomies to prevent Frey's syndrome and contour defects. The results of seven consecutive attempts revealed it to be an effective technique, achieving both goals in all patients with minimal morbidity.

Interaction of Urea with an Unfolded Protein. The DNA-binding Domain of the 434-repressor

FEBS Letters. Jun, 1995  |  Pubmed ID: 7789518

Experimental techniques are presented for the observation of the solvation of the unfolded form of a globular protein, the N-terminal 63-residue polypeptide from the 434 repressor, in 7 M aqueous urea solution by both water and urea. With the use of 15N-labelled urea it is demonstrated that the cross sections through two-dimensional nuclear Overhauser enhancement (NOE) spectra at the chemical shifts of H2O and urea both contain direct NOEs with the protein, under conditions where exchange peaks are observed only in the water cross section. A preliminary analysis of the data showed that the residence times of urea molecules in solvation sites near the methyl groups of Val, Leu and Ile are significantly longer than those of water molecules in the same sites.

Internal Brain Herniation in a Patient with Apert's Syndrome

Annals of Plastic Surgery. Apr, 1995  |  Pubmed ID: 7793791

Patients with Apert's syndrome typically exhibit craniosynostosis, exorbitism, midface hypoplasia, and symmetric syndactyly. There have also been occasional descriptions of the variable dysmorphology of the inner surface of the calvarium. We present a patient with Apert's syndrome who had an intracranial herniation of a portion of the frontal lobe through a ridge of ossified dura. The ridge and the gliotic cortical tissue were removed when the patient underwent repair of the hypertelorism at age six. Bone grafts for this repair were fashioned in part from the resected ridge. We believe this finding may be the result of a small dural tear that occurred during prior surgery.

Generation of Antigen-presenting Cells for Soluble Protein Antigens Ex Vivo from Peripheral Blood CD34+ Hematopoietic Progenitor Cells in Cancer Patients

European Journal of Immunology. Mar, 1996  |  Pubmed ID: 8605926

Peripheral blood CD34+ hematopoietic cells (PBPC) mediate hematopoietic reconstitution in cancer patients after autologous transplantation and can be expanded ex vivo in the presence of colony-stimulating factors. This study shows that functionally active antigen-presenting cells (APC) for soluble proteins are generated and expanded in these PBPC cultures. CD34+ cells were cultured ex vivo in medium containing stem cell factor, interleukin-1 beta (IL-1 beta), IL-3, IL-6, and erythropoietin (EPO). The cells from these cultures developed into very potent APC of tetanus toxoid and purified derivative of tuberculin for autologous T cells in vitro. The antigen-presenting capacity of these cell was maintained for at least 38 days of culture. These APC resembled immature cells of the myelomonocytic cell lineage by surface marker, immunocytochemistry and ultrastructural analysis. Such APC might be able to present antigens from certain tumors to the immune system.

NMR Structure of the Mouse Prion Protein Domain PrP(121-231)

Nature. Jul, 1996  |  Pubmed ID: 8700211

The 'protein only' hypothesis states that a modified form of normal prion protein triggers infectious neurodegenerative diseases, such as bovine spongiform encephalopathy (BSE), or Creutzfeldt-Jakob disease (CJD) in humans. Prion proteins are thought to exist in two different conformations: the 'benign' PrPcform, and the infectious 'scrapie form', PrPsc. Knowledge of the three-dimensional structure of PrPc is essential for understanding the transition to PrPsc. The nuclear magnetic resonance (NMR) structure of the autonomously folding PrP domain comprising residues 121-231 (ref. 6) contains a two-stranded antiparallel beta-sheet and three alpha-helices. This domain contains most of the point-mutation sites that have been linked, in human PrP, to the occurrence of familial prion diseases. The NMR structure shows that these mutations occur within, or directly adjacent to, regular secondary structures. The presence of a beta-sheet in PrP(121-231) is in contrast with model predictions of an all-helical structure of PrPc (ref. 8), and may be important for the initiation of the transition from PrPc to PrPsc.

Prevention of Splashing During High-pressure Irrigation of Contaminated Wounds

Plastic and Reconstructive Surgery. Sep, 1996  |  Pubmed ID: 8773705

Monitoring NMR Spectrometer Performance During Data Accumulation for Macromolecular Structure Determination

Journal of Magnetic Resonance. Series B. Mar, 1996  |  Pubmed ID: 8867449

The Use of the Labiocolumellar Crease Incision in Rhinoplasty

Annals of Plastic Surgery. Dec, 1996  |  Pubmed ID: 8988767

Aurel Rethi, in 1934, first described the transverse upper columellar incision for open rhinoplasty for resection of a portion of columella in cases of overly projecting nasal tip. The mid columellar incision has come to be known as the "Rethi" incision. Numerous variations of this approach have been popularized through the years. Recently, a great debate has raged over the criteria to be used in selecting patients for rhinoplasty. In this paper, we review 100 consecutive rhinoplasties and discuss our technique of labiocolumellar crease incision for open approach, and relate the criteria that we utilize to select patients for open rhinoplasty. There were 37 male and 63 female patients. Of these, 32 primary, 45 secondary, 18 cleft, and 5 reconstructive rhinoplasties were performed. Twenty-eight percent of primary, 62% of secondary, 78% of cleft, and 80% of reconstructive rhinoplasties were performed using the open approach via the labiocolumellar crease incision. There were no cases of circulatory compromise of the columella. The presence of a scar along the columella base (as with the C-flap in cleft patients) should be an indication for open rhinoplasty. Several myths about the labiocolumellar crease incision are dispelled. Adhering to principles of aesthetic subunits should guide the surgeon to place scars in a less noticeable position.

Simultaneous Osseous Genioplasty and Meloplasty

Plastic and Reconstructive Surgery. Apr, 1997  |  Pubmed ID: 9105353

A review was done of the records of 50 patients who had osseous genioplasty performed at the same sitting as face lifting and, in many cases, submental lipectomy over a 20-year period by the senior author. The types of genioplasties were sliding advancement (40), lengthening with interpositional bone graft (7), and reduction (3). In 9 patients, chin implants were removed, generally because of inadequate chin projection or implant erosion. Three patients were operated on under local anesthesia, the remainder under general anesthesia. Associated procedures, done in 46 patients, included rhinoplasty, forehead lifting, blepharoplasty, lateral canthopexy, excision of buccal fat pads, reduction mammaplasty, and abdominoplasty. In 4 patients, associated maxillofacial procedures were performed, including Le Fort I and III osteotomies, two-jaw surgery, mandibular advancement with sagittal splitting, and orbital expansion. The perceived advantages of osseous genioplasty were greater versatility in dealing with problems in other than the sagittal plane, the possibility of greater chin projection, and a tightening of the submental musculature. Complications occurred in 10 patients. These included two hematomas requiring aspiration in the office, a prolapsed submandibular gland requiring later excision, a transient weakness of the marginal mandibular nerve, a transient numbness of the lower lip on one side, four revisions of scars resulting from the face lifting, and one localized wound infection in the parasymphyseal area that resolved with oral antibiotics. The most common complaint, which came from 8 female patients at some time from 1 month to 3 years postoperatively, was that the chin was "too strong." In 6 of these patients, most of whom were operated on early in the series, some of the chin projection was reduced by burring. Osseous genioplasty can be performed safely along with face lifting and submental lipectomy. The degree of advancement necessary in aesthetic surgical patients is generally less than that required in reconstructive patients. Patient satisfaction is great unless the chin is overly advanced.

The NMR Solution Structure of the Non-classical Homeodomain from the Rat Liver LFB1/HNF1 Transcription Factor

Journal of Molecular Biology. Apr, 1997  |  Pubmed ID: 9126845

The nuclear magnetic resonance (NMR) solution structure of the non-classical homeodomain from the rat liver LFB1/HNF1 transcription factor was determined with the program DIANA from an input of 1356 nuclear Overhauser enhancement (NOE) upper distance constraints and 228 dihedral angle constraints collected using experiments with the unlabelled, the uniformly 15N-labelled and the uniformly 13C-labelled protein. Out of a group of 50 independently calculated conformers the 20 conformers with the smallest residual DIANA target function values were refined by energy minimization with the program OPAL and are used to represent the NMR structure. The average of the pairwise root-mean-square deviations (r.m.s.d.) of these 20 individual NMR conformers relative to the mean coordinates is 0.73 A (1 A = 0.1 nm) for the backbone atoms N, C(alpha) and C' of residues 15 to 82. The chain-terminal polypeptide segments 1-14 and 90-99 are disordered in solution. The globular fold contains three well-defined helices comprising the residues 19 to 29, 37 to 53 and 71 to 81, and the third helix is extended by a less well-ordered fourth helix with residues 82 to 89, which coincides with corresponding observations in "classical" homeodomains. Side-chain analysis resulted in 33 "best-defined" side-chains, with global displacements smaller than 1.1 A, and addition of these side-chains to the global superposition of residues 15 to 82 resulted in a r.m.s.d of 0.81 A. The protein contains two hydrophobic cores, one of which corresponds to the helical packing seen in classical homeodomains, while the other one stabilizes the conformation of the 21-residue insertion between helices II and III. The individual helices and their relative spatial arrangements are stabilized by a variety of structural motifs, which include medium-range and long-range hydrogen bonds and salt bridges. Detailed comparison with the Antennapedia homeodomain, and studies of the complex formation with an operator DNA half-site provided initial information on the DNA-binding mode of the LFB1/HNF1 homeodomain.

Prion Protein NMR Structure and Species Barrier for Prion Diseases

Proceedings of the National Academy of Sciences of the United States of America. Jul, 1997  |  Pubmed ID: 9207082

The structural basis of species specificity of transmissible spongiform encephalopathies, such as bovine spongiform encephalopathy or "mad cow disease" and Creutzfeldt-Jakob disease in humans, has been investigated using the refined NMR structure of the C-terminal domain of the mouse prion protein with residues 121-231. A database search for mammalian prion proteins yielded 23 different sequences for the fragment 124-226, which display a high degree of sequence identity and show relevant amino acid substitutions in only 18 of the 103 positions. Except for a unique isolated negative surface charge in the bovine protein, the amino acid differences are clustered in three distinct regions of the three-dimensional structure of the cellular form of the prion protein. Two of these regions represent potential species-dependent surface recognition sites for protein-protein interactions, which have independently been implicated from in vitro and in vivo studies of prion protein transformation. The third region consists of a cluster of interior hydrophobic side chains that may affect prion protein transformation at later stages, after initial conformational changes in the cellular protein.

Three-dimensional NMR Structure of a Self-folding Domain of the Prion Protein PrP(121-231)

Trends in Biochemical Sciences. Jul, 1997  |  Pubmed ID: 9255063

Recombinant Full-length Murine Prion Protein, MPrP(23-231): Purification and Spectroscopic Characterization

FEBS Letters. Aug, 1997  |  Pubmed ID: 9280297

The cellular prion protein of the mouse, mPrP(C), consists of 208 amino acids (residues 23-231). It contains a carboxy-terminal domain, mPrP(121-231), which represents an autonomous folding unit with three alpha-helices and a two-stranded antiparallel beta-sheet. We expressed the complete amino acid sequence of the prion protein, mPrP(23-231), in the cytoplasm of Escherichia coli. mPrP(23-231) was solubilized from inclusion bodies by 8 M urea, oxidatively refolded and purified to homogeneity by conventional chromatographic techniques. Comparison of near-UV circular dichroism, fluorescence and one-dimensional 1H-NMR spectra of mPrP(23-231) and mPrP(121-231) shows that the amino-terminal segment 23-120, which includes the five characteristic octapeptide repeats, does not contribute measurably to the manifestation of three-dimensional structure as detected by these techniques, indicating that the residues 121-231 might be the only polypeptide segment of PrP(C) with a defined three-dimensional structure.

NMR Characterization of the Full-length Recombinant Murine Prion Protein, MPrP(23-231)

FEBS Letters. Aug, 1997  |  Pubmed ID: 9280298

The recombinant murine prion protein, mPrP(23-231), was expressed in E. coli with uniform 15N-labeling. NMR experiments showed that the previously determined globular three-dimensional structure of the C-terminal domain mPrP(121-231) is preserved in the intact protein, and that the N-terminal polypeptide segment 23-120 is flexibly disordered. This structural information is based on nearly complete sequence-specific assignments for the backbone amide nitrogens, amide protons and alpha-protols of the polypeptide segment of residues 121-231 in mPrP(23-231). Coincidence of corresponding sequential and medium-range nuclear Overhauser effects (NOE) showed that the helical secondary structures previously identified in mPrP(121-231) are also present in mPrP(23-231), and near-identity of corresponding amide nitrogen and amide proton chemical shifts indicates that the three-dimensional fold of mPrP(121-231) is also preserved in the intact protein. The linewidths in heteronuclear 1H-15N correlation spectra and 15N[1H]-NOEs showed that the well structured residues 126-230 have correlation times of several nanoseconds, as is typical for small globular proteins, whereas correlation times shorter than 1 nanosecond were observed for all residues of mPrP(23-231) outside of this domain.

Biomphalaria Glabrata: Relevance of Albino Organisms As a Useful Tool for Environmental Lead Monitoring

Bulletin of Environmental Contamination and Toxicology. Nov, 1997  |  Pubmed ID: 9323235

Attenuated T2 Relaxation by Mutual Cancellation of Dipole-dipole Coupling and Chemical Shift Anisotropy Indicates an Avenue to NMR Structures of Very Large Biological Macromolecules in Solution

Proceedings of the National Academy of Sciences of the United States of America. Nov, 1997  |  Pubmed ID: 9356455

Fast transverse relaxation of 1H, 15N, and 13C by dipole-dipole coupling (DD) and chemical shift anisotropy (CSA) modulated by rotational molecular motions has a dominant impact on the size limit for biomacromolecular structures that can be studied by NMR spectroscopy in solution. Transverse relaxation-optimized spectroscopy (TROSY) is an approach for suppression of transverse relaxation in multidimensional NMR experiments, which is based on constructive use of interference between DD coupling and CSA. For example, a TROSY-type two-dimensional 1H,15N-correlation experiment with a uniformly 15N-labeled protein in a DNA complex of molecular mass 17 kDa at a 1H frequency of 750 MHz showed that 15N relaxation during 15N chemical shift evolution and 1HN relaxation during signal acquisition both are significantly reduced by mutual compensation of the DD and CSA interactions. The reduction of the linewidths when compared with a conventional two-dimensional 1H,15N-correlation experiment was 60% and 40%, respectively, and the residual linewidths were 5 Hz for 15N and 15 Hz for 1HN at 4 degrees C. Because the ratio of the DD and CSA relaxation rates is nearly independent of the molecular size, a similar percentagewise reduction of the overall transverse relaxation rates is expected for larger proteins. For a 15N-labeled protein of 150 kDa at 750 MHz and 20 degrees C one predicts residual linewidths of 10 Hz for 15N and 45 Hz for 1HN, and for the corresponding uniformly 15N,2H-labeled protein the residual linewidths are predicted to be smaller than 5 Hz and 15 Hz, respectively. The TROSY principle should benefit a variety of multidimensional solution NMR experiments, especially with future use of yet somewhat higher polarizing magnetic fields than are presently available, and thus largely eliminate one of the key factors that limit work with larger molecules.

[Changes in the Levels of Delta-aminolevulinic Acid Dehydratase in Chronic Alcoholic Patients]

Medicina. 1997  |  Pubmed ID: 9640759

Medical and biochemical analysis were performed on 58 patients with chronic alcoholism. In accordance with medical characterisation, patients were divided in three groups: A (patients having only hepatopathy), B (patients with hepatopathy and neuropathy) and C (patients having only alcoholic neuropathy). Simultaneously, several parameters related to heme biosynthesis were examined. Urinary delta-aminolevulic acid (ALA), porphobilinogen (PBG) and porphyrins and fecal porphyrins measurements did not show significant difference among all studied groups. The activities of ALA-dehydratase (ALA-D), uroporphyrinogen-I-synthase (URO-I-S) and uroporphyrinogen-III-synthase (URO-III-S) were monitored in peripheral erythrocytes. From the enzymes measured, only ALA-D levels in groups B and C were significantly depressed (p < 0.002) compared with normal subjects. The decrease in ALA-D correlated with the degree of neuropathy.

The Frontonasal Flap for Increased Exposure in Posttraumatic Nasal Deformity: a Technical Overview

The Journal of Cranio-maxillofacial Trauma. 1997  |  Pubmed ID: 11951272

Nasal reconstruction continues to be a surgical challenge. The prominent location of the nose, the unique quality and texture of its skin, and the intricacies of its cartilaginous and bony infrastructure demand careful attention to fine detail. Attempts to refine reconstructive techniques have resulted in a myriad of local flaps. The frontonasal flap is well-described and reliable, but it is infrequently used. A brief review of the literature is presented. The authors describe a unique case of a 64-year-old woman with posttraumatic nasal tip and dorsal deformity. The frontonasal flap provided soft tissue coverage for the nasal tip and allowed excellent exposure for reconstruction of the hard nasal framework with cartilage and bone grafts. It provides local tissue with excellent contour, color, and texture match, and can be performed in one stage.

Solvent Magnetization Artifacts in High-field NMR Studies of Macromolecular Hydration

Journal of Magnetic Resonance (San Diego, Calif. : 1997). Feb, 1998  |  Pubmed ID: 9500888

With the use of high magnetic fields and improved quality factor ratings of the probeheads in modern NMR spectrometers, radiation damping becomes more and more important. In addition, the demagnetizing field effect from protonated solvents gains significance with the increase of the magnetic field strength. During a typical NMR pulse sequence the magnetic fields caused by these effects become time-dependent, which makes the system nonlinear and may, for example, measurably influence the precession frequencies of all nuclei in the sample. Since radiation damping can affect signals that are several kilohertz away from the solvent resonance, the amplitude, phase, and frequency of the desired signals can be disturbed so as to give rise to spectral artifacts. In particular when difference methods are used to obtain the final spectrum, the data sets may be severely deteriorated by such artifacts. This paper investigates effects from the demagnetizing field and from radiation damping with a selection of pulse sequences in use for studies of macromolecular hydration, and strategies are described for the detection and elimination of the ensuing artifacts.

Prion Protein Structural Features Indicate Possible Relations to Signal Peptidases

FEBS Letters. Apr, 1998  |  Pubmed ID: 9600253

Transmissible spongiform encephalopathies (TSEs) in mammalian species are believed to be caused by an oligomeric isoform, PrP(Sc), of the cellular prion protein, PrP(C). One of the key questions in TSE research is how the observed accumulation of PrP(Sc), or possibly the concomitant depletion of PrP(C) can cause fatal brain damage. Elucidation of the so far unknown function of PrP(C) is therefore of crucial importance. PrP(C) is a membrane-anchored cell surface protein that possesses a so far unique three-dimensional structure. While the N-terminal segment 23-120 of PrP(C) is flexibly disordered, its C-terminal residues 121-231 form a globular domain with three alpha-helices and a two-stranded beta-sheet. Here we report the observation of structural similarities between the domain of PrP(121-231) and the soluble domains of membrane-anchored signal peptidases. At the level of the primary structure we find 23% identity and 41% similarity between residues 121-217 of the C-terminal domain of murine PrP and a catalytic domain of the rat signal peptidase. The invariant PrP residues Tyr-128 and His-177 align with the two presumed active-site residues of signal peptidases and are in close spatial proximity in the three-dimensional structure of PrP(121-231).

Prion Protein NMR Structure and Familial Human Spongiform Encephalopathies

Proceedings of the National Academy of Sciences of the United States of America. Sep, 1998  |  Pubmed ID: 9751723

The refined NMR structure of the mouse prion protein domain mPrP(121-231) and the recently reported NMR structure of the complete 208-residue polypeptide chain of mPrP are used to investigate the structural basis of inherited human transmissible spongiform encephalopathies. In the cellular form of mPrP no spatial clustering of mutation sites is observed that would indicate the existence of disease-specific subdomains. A hydrogen bond between residues 128 and 178 provides a structural basis for the observed highly specific influence of a polymorphism in position 129 in human PrP on the disease phenotype that segregates with the mutation Asp-178-Asn. Overall, the NMR structure implies that only part of the disease-related amino acid replacements lead to reduced stability of the cellular form of PrP, indicating that subtle structural differences in the mutant proteins may affect intermolecular signaling in a variety of different ways.

TROSY in Triple-resonance Experiments: New Perspectives for Sequential NMR Assignment of Large Proteins

Proceedings of the National Academy of Sciences of the United States of America. Nov, 1998  |  Pubmed ID: 9811843

The NMR assignment of 13C, 15N-labeled proteins with the use of triple resonance experiments is limited to molecular weights below approximately 25,000 Daltons, mainly because of low sensitivity due to rapid transverse nuclear spin relaxation during the evolution and recording periods. For experiments that exclusively correlate the amide proton (1HN), the amide nitrogen (15N), and 13C atoms, this size limit has been previously extended by additional labeling with deuterium (2H). The present paper shows that the implementation of transverse relaxation-optimized spectroscopy ([15N,1H]-TROSY) into triple resonance experiments results in several-fold improved sensitivity for 2H/13C/15N-labeled proteins and approximately twofold sensitivity gain for 13C/15N-labeled proteins. Pulse schemes and spectra recorded with deuterated and protonated proteins are presented for the [15N, 1H]-TROSY-HNCA and [15N, 1H]-TROSY-HNCO experiments. A theoretical analysis of the HNCA experiment shows that the primary TROSY effect is on the transverse relaxation of 15N, which is only little affected by deuteration, and predicts sensitivity enhancements that are in close agreement with the experimental data.

Dialogue. Industry Consolidation: What's at Stake for Consumers and Purchasers?

Behavioral Healthcare Tomorrow. Aug, 1998  |  Pubmed ID: 10182151

The behavioral healthcare field has undergone massive consolidation, especially in the last year. Health plans, hospital systems, and community-based organizations have all been affected. Economists argue that consolidation is a logical consequence of the current, competitive healthcare market. But consumers and purchasers wonder if the mergers and acquisitions will benefit them. Efficient markets are supposed to stimulate competition in ways that reward purchasers and consumers of services. When prices go down and quality improves as a result of competitive market forces, then the market has functioned properly and has served its purpose. Behavioral healthcare, however, is an essential human service, not a commodity. And the consumers and purchasers of healthcare are typically not the same person or entity, which also makes the healthcare market different from the markets for cars, computers, food, or any other type of consumer product. More than 100 million Americans now receive managed behavioral health benefits from only three companies. With such intense power concentrated in the hands of such a small number of providers, the time has come to evaluate the impact of the consolidation trend. In the following dialogue article, leaders, representing different interest groups review the benefits and risks of massive industry consolidation, and propose solutions to the critical challenges that it raises.

Single Transition-to-single Transition Polarization Transfer (ST2-PT) in [15N,1H]-TROSY

Journal of Biomolecular NMR. Aug, 1998  |  Pubmed ID: 21136330

This paper describes the use of single transition-to-single transition polarization transfer (ST2-PT) in transverse relaxation-optimized spectroscopy (TROSY), where it affords a [Formula: see text] sensitivity enhancement for kinetically stable amide 15N-1H groups in proteins. Additional, conventional improvements of [15N,1H]-TROSY include that signal loss for kinetically labile 15N-1H groups due to saturation transfer from the solvent water is suppressed with the 'water flip back' technique and that the number of phase steps is reduced to two, which is attractive for the use of [15N,1H]-TROSY as an element in more complex NMR schemes. Finally, we show that the impact of the inclusion of the 15N steady-state magnetization (Pervushin et al., 1998) on the signal-to-noise ratio achieved with [15N,1H]-TROSY exceeds by up to two-fold the gain expected from the gyromagnetic ratios of 1H and 15N.

Polarization Transfer by Cross-correlated Relaxation in Solution NMR with Very Large Molecules

Proceedings of the National Academy of Sciences of the United States of America. Apr, 1999  |  Pubmed ID: 10220394

In common multidimensional NMR experiments for studies of biological macromolecules in solution, magnetization transfers via spin-spin couplings [insensitive nuclei enhanced by polarization transfer (INEPT)] are key elements of the pulse schemes. For molecular weights beyond 100,000, transverse relaxation during the transfer time may become a limiting factor. This paper presents a transfer technique for work with big molecules, cross relaxation-enhanced polarization transfer (CRINEPT), which largely reduces the size limitation of INEPT transfers with the use of cross-correlated relaxation-induced polarization transfer. The rate of polarization transfer by cross-correlated relaxation is proportional to the rotational correlation time, so that it becomes a highly efficient transfer mechanism for solution NMR with very high molecular weights. As a first implementation, [15N,1H]-correlation experiments were designed that make use of cross-correlation between dipole-dipole coupling and chemical shift anisotropy of the 15N---1H-moieties for both CRINEPT and transverse relaxation-optimized spectroscopy (TROSY). When compared with INEPT-based [15N,1H]-TROSY, these experiments yielded up to 3-fold signal enhancement for amide groups of a 110,000-Da protein in aqueous solution at 4 degrees C. CRINEPT opens avenues for solution NMR with supramolecular structures such as membrane proteins solubilized in micelles or lipid vesicles, proteins attached to nucleic acid fragments, or oligomeric proteins.

Photostimulable Storage Phosphor Image Acquisition: Evaluation of Three Commercially Available State-of-the-art Systems

Journal of Digital Imaging. May, 1999  |  Pubmed ID: 10342166

Photostimulable storage phosphor (PSP) image acquisition systems have been available for several years. The technology has had the opportunity to mature; however, there has not been an independent comparison of recently marketed commercial systems. For this study, three computed radiography (CR) systems using PSP technology (Kodak CR System 400 with autoloader [Eastman Kodak, Rochester, NY], Fuji FCR AC-3CS [Fuji Medical Systems, Stamford, CT], and Agfa ADC Compact [Bayer Corp, Ridgefield Park, NJ]) were connected to an IBM RadWorks diagnostic radiology workstation (IBM Corp, White Plains, NY) and evaluated for conformance to their performance specifications using guidance provided in the most recent draft acceptance testing protocol from Task Group No. 10, American Association of Physicists in Medicine. In addition, the physical requirements (e.g., space and power) and connectivity to another manufacturer's diagnostic workstation were examined. X-ray technologist comfort with each PSP imaging system and an assessment by our supporting biomedical equipment maintenance activity of their ability to service each PSP imaging system were also considered.

[13C]-constant-time [15N,1H]-TROSY-HNCA for Sequential Assignments of Large Proteins

Journal of Biomolecular NMR. May, 1999  |  Pubmed ID: 10382310

The greatly improved sensitivity resulting from the use of TROSY during 15N evolution and amide proton acquisition enables the recording of HNCA spectra of large proteins with constant-time 13C alpha evolution. In [13C]-ct-[15N,1H]-TROSY-HNCA experiments with a 2H/13C/15N-labeled 110 kDa protein, 7,8-dihydroneopterin aldolase from Staphylococcus aureus, nearly all correlation peaks seen in the [15N,1H]-TROSY-HNCA spectrum were also detected. The improved resolution in the 13C dimension then enabled a significant number of sequential assignments that could not be obtained with [15N,1H]-TROSY-HNCA without [13C]-constant-time period.

NMR Structure of the Sea Urchin (Strongylocentrotus Purpuratus) Metallothionein MTA

Journal of Molecular Biology. Aug, 1999  |  Pubmed ID: 10438629

The three-dimensional structure of [(113)Cd7]-metallothionein-A (MTA) of the sea urchin Strongylocentrotus purpuratus was determined by homonuclear(1)H NMR experiments and heteronuclear [(1)H, (113)Cd]-correlation spectroscopy. MTA is composed of two globular domains, an N-terminal four-metal domain of the amino acid residues 1 to 36 and a Cd4Cys11cluster, and a C-terminal three-metal domain including the amino acid residues 37 to 65 and a Cd3Cys9cluster. The structure resembles the known mammalian and crustacean metallothioneins, but has a significantly different connectivity pattern of the Cys-metal co-ordination bonds and concomitantly contains novel local folds of some polypeptide backbone segments. These differences can be related to variations of the Cys sequence positions and thus emphasize the special role of the cysteine residues in defining the structure of metallothioneins, both on the level of the domain architecture and the topology of the metal-thiolate clusters.

The 3D NOESY-[(1)H,(15)N,(1)H]-ZQ-TROSY NMR Experiment with Diagonal Peak Suppression

Proceedings of the National Academy of Sciences of the United States of America. Aug, 1999  |  Pubmed ID: 10449740

In our 3D NOESY-[(1)H,(15)N,(1)H]-ZQ-TROSY experiment, the TROSY principle (transverse relaxation-optimized spectroscopy) is used in three-dimensional (3D) (15)N-resolved nuclear Overhauser enhancement spectroscopy (NOESY), which enables resonance assignments by sequential nuclear Overhauser effects and the collection of structural constraints in large (15)N- or (2)H,(15)N-labeled proteins. Our experiment affords optimization of the transverse relaxation in all three frequency dimensions, provides suppression of the strong diagonal autorelaxation peaks, which otherwise tend to interfere with the analysis of nearby informative crosspeaks, and yields improved resolution for the entire spectrum when compared with conventional 3D (15)N-resolved-[(1)H,(1)H]-NOESY, because of the narrower lineshapes along both proton dimensions. The key element of this experiment is an approach for correlating the (15)N and (1)H chemical shifts with two-dimensional ZQ-[(15)N,(1)H]-TROSY, where zero-quantum (ZQ) coherence is generated and the remote cross-correlation between the (1)H and (15)N chemical shift anisotropy interactions is used to reduce transverse relaxation during (15)N evolution. Practical applications are illustrated with spectra of a protein with a molecular mass of 110,000 Da.

NMR Spectroscopy of Large Molecules and Multimolecular Assemblies in Solution

Current Opinion in Structural Biology. Oct, 1999  |  Pubmed ID: 10508768

New strategies and technical advances in NMR spectroscopy and biochemical methods for isotope labeling have enabled solution NMR studies of biomacromolecular systems of 100 kDa and larger. Recent progress has been made, in particular, with techniques for sequential resonance assignments, novel approaches for the direct observation of hydrogen bonds in nucleic acids and proteins, and segmental isotope labeling.

Improved Sensitivity and Coherence Selection for [15N,1H]-TROSY Elements in Triple Resonance Experiments

Journal of Biomolecular NMR. Oct, 1999  |  Pubmed ID: 10605091

In experiments with proteins of molecular weights around 100 kDa the implementation of [15N,1H]-TROSY-elements in [15N]-constant-time triple resonance experiments yields sensitivity enhancements of one to two orders of magnitude. An additional gain of 10 to 20% may be obtained with the use of 'sensitivity enhancement elements'. This paper describes a novel sensitivity enhancement scheme which is based on concatenation of the 13C alpha-->15N magnetization transfer with the ST2-PT element, and which enables proper TROSY selection of the 15N multiplet components.

UK Medical Charities and Clinical Trials

The British Journal of General Practice : the Journal of the Royal College of General Practitioners. Sep, 1999  |  Pubmed ID: 10756628

NMR Solution Structure of the Human Prion Protein

Proceedings of the National Academy of Sciences of the United States of America. Jan, 2000  |  Pubmed ID: 10618385

The NMR structures of the recombinant human prion protein, hPrP(23-230), and two C-terminal fragments, hPrP(90-230) and hPrP(121-230), include a globular domain extending from residues 125-228, for which a detailed structure was obtained, and an N-terminal flexibly disordered "tail." The globular domain contains three alpha-helices comprising the residues 144-154, 173-194, and 200-228 and a short anti-parallel beta-sheet comprising the residues 128-131 and 161-164. Within the globular domain, three polypeptide segments show increased structural disorder: i.e., a loop of residues 167-171, the residues 187-194 at the end of helix 2, and the residues 219-228 in the C-terminal part of helix 3. The local conformational state of the polypeptide segments 187-193 in helix 2 and 219-226 in helix 3 is measurably influenced by the length of the N-terminal tail, with the helical states being most highly populated in hPrP(23-230). When compared with the previously reported structures of the murine and Syrian hamster prion proteins, the length of helix 3 coincides more closely with that in the Syrian hamster protein whereas the disordered loop 167-171 is shared with murine PrP. These species variations of local structure are in a surface area of the cellular form of PrP that has previously been implicated in intermolecular interactions related both to the species barrier for infectious transmission of prion disease and to immune reactions.

Sensitivity Gain by Simultaneous Acquisition of Two Coherence Pathways: the HNCA(+) Experiment

Journal of Magnetic Resonance (San Diego, Calif. : 1997). Mar, 2000  |  Pubmed ID: 10698664

In most multidimensional nuclear magnetic resonance experiments a single and distinct coherence transfer pathway is selected by phase cycling or by pulsed field gradients. It was shown that simultaneously exploiting more than one coherence transfer pathway could increase the overall sensitivity of NMR experiments. However, sensitivity enhancement schemes described to date introduce additional delays in the pulse schemes, resulting in considerable decrease of the expected sensitivity gain when applied to biomolecules due their fast transverse relaxation. A novel sensitivity enhancement principle which increases sensitivity of an experiment by simultaneously exploiting two completely independent coherence pathways in a single NMR pulse scheme is presented in this paper. As an example an improved HNCA experiment, the HNCA(+), is presented, which combines the "out-and-back" coherence transfer pathway used in HNCA with an "out-and-stay" experiment, analogous to HCANH, without adding any time periods compared to the conventional HNCA pulse sequence. The applicability of the HNCA(+) was theoretically evaluated with regard to different sizes of peptides or proteins, which showed that the experimental time can be reduced twofold in ideal cases. The application of this novel experiment to a 7-kDa protein showed a 20% sensitivity gain of HNCA(+) when compared to conventional HNCA.

NMR Experiments for Resonance Assignments of 13C, 15N Doubly-labeled Flexible Polypeptides: Application to the Human Prion Protein HPrP(23-230)

Journal of Biomolecular NMR. Feb, 2000  |  Pubmed ID: 10723992

A combination of three heteronuclear three-dimensional NMR experiments tailored for sequential resonance assignments in uniformly 15N, 13C-labeled flexible polypeptide chains is described. The 3D (H)N(CO-TOCSY)NH, 3D (H)CA(CO-TOCSY)NH and 3D (H)CBCA(CO-TOCSY)NH schemes make use of the favorable 15N chemical shift dispersion in unfolded polypeptides, exploit the slow transverse 15N relaxation rates of unfolded polypeptides in high resolution constant-time [1H, 15N]-correlation experiments, and use carbonyl carbon homonuclear isotropic mixing to transfer magnetization sequentially along the amino acid sequence. Practical applications are demonstrated with the 100-residue flexible tail of the recombinant human prion protein, making use of spectral resolution up to 0.6 Hz in the 15N dimension, simultaneous correlation with the two adjacent amino acid residues to overcome problems associated with spectral overlap, and the potential of the presently described experiments to establish nearest-neighbor correlations across proline residues in the amino acid sequence.

Picture Archiving and Communication Systems Project Management Using Web-based Tools

Journal of Digital Imaging. May, 2000  |  Pubmed ID: 10847404

As the technology of picture archiving and communications systems (PACS) improves and implementation becomes more widespread, the project management of deploying substantially large, multiple-facility systems becomes an integral part of success. A successful deployment requires project support from the initial planning and surveying to the final acceptance, even encompassing support during active use of the PACS. The sharing of information between project stakeholders of a PACS implementation can be daunting at times, but with the flexibility of the worldwide web, this aspect can be eased. This report speaks to the tools and usability of the worldwide web to disseminate project management information for planning, implementation, and support of any PACS implementation--anywhere. This sharing of knowledge prepares the end user for what will be available for them when the complete systems is in place, allowing for a smoother migration to PACS.

Planning Factors for Developing an Enterprise-wide Picture Archiving and Communication System Maintenance Program

Journal of Digital Imaging. May, 2000  |  Pubmed ID: 10847412

Picture archiving and communication system (PACS) maintenance on an individual site basis has historically been a complex and costly challenge. With the advent of enterprise-wide PACS projects such as the Virtual Radiology Environment (VRE) project, the challenge of a maintenance program with even more complexities has presented itself. The approach of the project management team for the VRE project is not one of reactive maintenance, but one of highly proactive planning and negotiations, in hopes of capitalizing on the economies of scale of an enterprise-wide PACS maintenance program. A proactive maintenance program is one aspect of life-cycle management. As with any capital acquisition, life-cycle management may be used to manage the specific project aspects related to PACS. The purpose of an enterprise-wide warranty and maintenance life-cycle management approach is to maintain PACS at its maximum operational efficiency and utilization levels through a flexible, shared, yet symbiotic relationship between local, regional, and vendor resources. These goals include providing maximum operational performance levels on a local, regional, and enterprise basis, while maintaining acceptable costs and resource utilization levels. This goal must be achieved without negatively impacting point of care activities, regardless of changes to the clinical business environment.

Unilateral Mydriasis After Nasal Reconstruction Surgery

Canadian Journal of Anaesthesia = Journal Canadien D'anesthésie. Nov, 2000  |  Pubmed ID: 11097544

To present a case of iatrogenic, unilateral pupillary dilatation after general anesthesia for nasal surgery. Unilateral pupillary dilatation after general anesthesia has sinister implications, which might prompt further investigations. However, in patients undergoing nasal surgery, it might be caused by the action of drugs injected intranasally. Consideration of iatrogenic causes of pupillary dilatation might help clinicians to avoid time-consuming and costly investigations.

Structure Determination of Biological Macromolecules in Solution Using Nuclear Magnetic Resonance Spectroscopy

BioTechniques. Dec, 2000  |  Pubmed ID: 11126132

A detailed understanding of the function of a biological macromolecule requires knowledge of its three-dimensional structure. Most atomic-resolution structures of biological macromolecules have been solved either by X-ray diffraction in single crystals or by nuclear magnetic resonance (NMR) in solution. This review surveys the method of NMR structure determination. First, a brief introduction to NMR and its basic concepts is presented. The main part of the article deals with the individual steps necessary for an NMR structure determination. At the end, the discussion turns to considerations on the influence of the molecular size of the macromolecules on the structure determination by NMR. New techniques are discussed that greatly enhance the possibilities of applying NMR to large molecular systems.

Atomically Resolved Images from Near Node Photoelectron Holography Experiments on Al(111)

Physical Review Letters. Mar, 2001  |  Pubmed ID: 11289923

Szöke's concept for electron holography is hampered by forward scattering that dominates electron diffraction from electron point sources below the surface top layer. Forward scattering was proposed to be suppressed if the anisotropic nature of the electron source wave is exploited [T. Greber and J. Osterwalder, Chem. Phys. Lett. 256, 653 (1996)]. Experiments show a strong suppression of forward scattering in Al(111) if Al 2s photoelectrons (E(kin) = 952 eV) are measured near the nodal plane of the outgoing p wave. The holographic reconstruction from such diffraction data provides three dimensional images of atomic sites in unit cells with a size of more than 10 A.

Enhanced in Vitro Induced Production of Interleukin 10 by Peripheral Blood Mononuclear Cells in Rheumatoid Arthritis is Associated with Clinical Response to Methotrexate Treatment

The Journal of Rheumatology. Mar, 2001  |  Pubmed ID: 11296948

To investigate the effect of in vivo treatment with methotrexate (MTX) on the regulation of ex vivo interleukin 10 (IL-10) production by peripheral blood mononuclear cells (PBMC) derived from patients with rheumatoid arthritis (RA).

Size-dependent Melting of Self-assembled Indium Nanostructures

Physical Review Letters. Aug, 2001  |  Pubmed ID: 11531576

We have measured the melting temperature of nanoscale indium islands on a WSe(2) substrate using perturbed angular correlations combined with scanning tunneling microscopy. The indium islands are self-assembled nanostructures whose diameter can vary between about 5 and 100 nm, depending on deposition conditions. The melting point decreases due to surface energies as the islands get smaller. This decrease depends on the faceting of the crystalline nanostructures and interactions between the islands and the substrate.

Modeling Pentachlorophenol Bioavailability and Bioaccumulation by the Freshwater Fingernail Clam Sphaerium Corneum Using Artificial Particles and Humic Acids

Environmental Toxicology and Chemistry / SETAC. Dec, 2001  |  Pubmed ID: 11764179

The uptake of anthropogenic chemicals by benthic bivalves may occur through the water phase and also by the ingestion of particles from both the suspended matter and bottom sediments. Many chemicals sorb to sediments and, subsequently, are released in the digestive tract of animals. The assessment of sediment-bound chemicals has been difficult because of the complexity of the association between these chemicals and natural particles. To simplify this complexity, we previously devised a test system using artificial particles with known chemical structures. In the present work, we improved this experimental design by adding humic materials as a source of organic matter. Bioassays were conducted by exposing the fingernail clam Sphaerium corneum to sublethal levels of pentachlorophenol (PCP) in the presence or absence of the artificial particles, treated with or without a commercial preparation of humic acids. The results showed that the bioavailability and bioaccumulation could be explained on the basis of the interactions of PCP with the active groups and/or the backbone of the resins, both in systems with or without humic acids. This model may constitute a useful approach to modeling and predicting the uptake and accumulation of chemicals bound to natural sediments.

Evidence of Differences in the Biotransformation of Organic Contaminants in Three Species of Freshwater Invertebrates

Environmental Pollution (Barking, Essex : 1987). 2002  |  Pubmed ID: 11926182

Acute static bioassays were performed using three freshwater invertebrate species (the oligochaete Lumbriculus variegatus, the fingernail clam Sphaerium corneum and the larvae Chironomus riparius) exposed separately to a variety of 14C radiolabelled contaminants. The aim of this work was to investigate if the chemicals remained as parent compounds after the treatments. Chemicals used were 2,4-dichlorophenol; 2,4,5-trichlorophenol; pentachlorophenol; pyrene; Fenpropidin, and Trifluralin. Homogenates of the whole body tissue of each organism were prepared and total radioactivity was measured. Contaminants were then extracted into organic solvents and analysed by high-pressure liquid chromatography techniques. Chromatograms showed that most of the substances extracted were present as parent compounds in S. corneum and in L. variegatus. In contrast, for C. riparius a low proportion of the chemicals was recovered as parent compounds. These results suggest that different metabolic processes could take place in the different species.

[Acupuncture for Back Pain: Meta-analysis of Randomised Controlled Trials and an Update with Data from the Most Recent Studies]

Schmerz (Berlin, Germany). Apr, 2002  |  Pubmed ID: 11956898

Acupuncture is commonly used to treat back pain. A meta-analysis of clinical trials of acupuncture for this condition came to a positive conclusion whilst a qualitative review was negative.

Lipid-protein Interactions in DHPC Micelles Containing the Integral Membrane Protein OmpX Investigated by NMR Spectroscopy

Proceedings of the National Academy of Sciences of the United States of America. Oct, 2002  |  Pubmed ID: 12370417

Intermolecular nuclear Overhauser effects (NOEs) between the integral outer membrane protein OmpX from Escherichia coli and dihexanoylphosphatidylcholine (DHPC) provided a detailed description of protein-detergent interactions. The NOEs were measured in 3D (15)N- and (13)C-resolved [(1)H,(1)H]-NOESY spectra recorded with selectively methyl-protonated and otherwise uniformly (2)H,(13)C,(15)N-labeled OmpX in micelles of DHPC at natural isotope abundance. In these mixed micelles the NMR structure of OmpX consists of an eight-stranded antiparallel beta-barrel. The OmpX surface area covered with intermolecular NOEs to the DHPC hydrophobic tails forms a continuous cylinder jacket of approximately 28 A in height, which is centered about the middle of the long axis through the beta-barrel. In addition, some intermolecular NOEs with methyl groups of the DHPC polar head were identified along both boundaries of this cylinder jacket. The experimental data suggest that the hydrophobic surface areas of OmpX are covered with a monolayer of DHPC molecules, which appears to mimic quite faithfully the embedding of the beta-barrel in a double-layer lipid membrane.

Differential Expression of Inflammatory Mediators in Radiation-impaired Wound Healing

The Journal of Surgical Research. Sep, 2002  |  Pubmed ID: 12384069

Radiation impairs healing, although the underlying mechanisms are not clearly defined. Normal healing requires a fine balance of promoting and inhibiting factors. We hypothesize that there may be a down-regulation of promoting factors (nitric oxide) and, in turn, an up-regulation of healing inhibiting factors (TNF-alpha and IFN-gamma) in the wound after radiation.

Side Chain NMR Assignments in the Membrane Protein OmpX Reconstituted in DHPC Micelles

Journal of Biomolecular NMR. Aug, 2002  |  Pubmed ID: 12398349

Sequence-specific assignments have been obtained for side chain methyl resonances of Val, Leu and Ile in the outer membrane protein X (OmpX) from Escherichia coli reconstituted in 60 kDa micelles in aqueous solution. Using previously established techniques, OmpX was uniformly 2H,13C,15N-labeled with selectively protonated Val-gamma(1,2), Leu-delta(1,2) and Ile-delta1 methyl groups. The thus labeled protein was studied with the novel experiments 3D (H)C(CC)-TOCSY-(CO)-[15N,1H]-TROSY and 3D H(C)(CC)-TOCSY-(CO)-[15N,1H]-TROSY. Compared to the corresponding conventional experimental schemes, the TROSY-type experiments yielded a sensitivity gain of about 2 at 500 MHz. The overall sensitivity of the experiments was further enhanced more than two-fold by the use of a cryoprobe. Complete assignments of the proton and carbon chemical shifts were obtained for all isopropyl methyl groups of Val and Leu, as well as for the delta1-methyls of Ile. The present approach is applicable for soluble proteins or micelle-reconstituted membrane proteins in structures with overall molecular weights up to about 100 kDa, and adds to the potentialities of solution NMR for de novo structure determination as well as for functional studies, such as ligand screening with proteins in large structures.

Medical Research Charities Should Fund More Trials

BMJ (Clinical Research Ed.). Nov, 2002  |  Pubmed ID: 12446554

Influence of Particle Characteristics and Organic Matter Content on the Bioavailability and Bioaccumulation of Pyrene by Clams

Environmental Pollution (Barking, Essex : 1987). 2003  |  Pubmed ID: 12475068

Hydrophobic chemicals are known to associate with sediment particles including those from both suspended particulate matter and bottom deposits. The complex and variable composition of natural particles makes it very difficult therefore, to predict the bioavailability of sediment-bound contaminants. To overcome these problems we have previously devised a test system using artificial particles, with or without humic acids, for use as an experimental model of natural sediments. In the present work we have applied this experimental technique to investigate the bioavailability and bioaccumulation of pyrene by the freshwater fingernail clam Sphaerium corneum. The uptake and accumulation of pyrene in clams exposed to the chemical in the presence of a sample of natural sediment was also investigated. According to the results obtained, particle surface properties and organic matter content are the key factors for assessing the bioavailability and bioaccumulation of pyrene by clams.

Stereospecific Assignments of the Isopropyl Methyl Groups of the Membrane Protein OmpX in DHPC Micelles

Journal of Biomolecular NMR. Dec, 2003  |  Pubmed ID: 14512734

In NMR studies of large molecular structures, the number of conformational constraints based on NOE measurements is typically limited due to the need for partial deuteration. As a consequence, when using selective protonation of peripheral methyl groups on a perdeuterated background, stereospecific assignments of the diastereotopic methyl groups of Val and Leu can have a particularly large impact on the quality of the NMR structure determination. For example, 3D 15N- and 13C-resolved [1H,1H]-NOESY spectra of the E. Coli membrane protein OmpX in mixed micelles with DHPC, which have an overall molecular weight of about 60 kDa, showed that about 50% of all obtainable NOEs involve the diastereotopic methyl groups of Val and Leu. In this paper, we used biosynthetically-directed fractional 13C labeling of OmpX and [13C,1H]-HSQC spectroscopy to obtain stereospecific methyl assignments of Val and Leu in OmpX/DHPC. For practical purposes it is of interest that this data could be obtained without use of a deuterated background, and that combinations of NMR experiments have been found for obtaining the desired information either at a 1H frequency of 500 MHz, or with significantly reduced measuring time on a high-frequency instrument.

NMR Structure of the Apoptosis- and Inflammation-related NALP1 Pyrin Domain

Structure (London, England : 1993). Oct, 2003  |  Pubmed ID: 14527388

Signaling in apoptosis and inflammation is often mediated by proteins of the death domain superfamily in the Fas/FADD/Caspase-8 or the Apaf-1/Caspase-9 pathways. This superfamily currently comprises the death domain (DD), death effector domain (DED), caspase recruitment domain (CARD), and pyrin domain (PYD) subfamilies. The PYD subfamily is most abundant, but three-dimensional structures are only available for the subfamilies DD, DED, and CARD, which have an antiparallel arrangement of six alpha helices as common fold. This paper presents the NMR structure of PYD of NALP1, a protein that is involved in the innate immune response and is a component of the inflammasome. The structure of NALP1 PYD differs from all other known death domain superfamily structures in that the third alpha helix is replaced by a flexibly disordered loop. This unique feature appears to relate to the molecular basis of familial Mediterranean fever (FMF), a genetic disease caused by single-point mutations.

Dissection of Heteronuclear NMR Experiments for Studies of Magnetization Transfer Efficiencies

Journal of Magnetic Resonance (San Diego, Calif. : 1997). Nov, 2003  |  Pubmed ID: 14568519

Modern NMR experiments for applications with biological macromolecules in solution typically include multiple magnetization transfer steps. When working with large structures, a significant fraction of the magnetization is lost during these transfers. For the design and optimization of complex experimental schemes, the magnetization transfer efficiencies have therefore commonly been calculated from the spin relaxation times. This paper now suggests a new method for measurement of individual transfer efficiencies directly with the system of interest, using short, reliable experiments. Initial applications of this approach with a 110,000 Da protein indicate that there is a wide range of transfer efficiencies among individual spin pairs in a structure of this size, which leads to a correspondingly large variation of the individual signal intensities and the need for techniques to enhance the weak signals.

TROSY in NMR Studies of the Structure and Function of Large Biological Macromolecules

Current Opinion in Structural Biology. Oct, 2003  |  Pubmed ID: 14568611

Transverse relaxation-optimized spectroscopy (TROSY), in combination with various isotope-labeling techniques, has opened avenues to study biomolecules with molecular masses of up to 1000000Da by solution NMR. Important recent applications of TROSY include the structure determination of membrane proteins in detergent micelles, structural and functional studies of large proteins in both monomeric form and macromolecular complexes, and investigations of intermolecular interactions in large complexes. TROSY improves the measurement of residual dipolar couplings and the detection of scalar couplings across hydrogen bonds - techniques that promise to further enhance the determination of solution structures of large proteins and oligonucleotides.

CAM Research Funding in the UK: Surveys of Medical Charities in 1999 and 2002

Complementary Therapies in Medicine. Sep, 2003  |  Pubmed ID: 14659380

A custom-made questionnaire was sent to all UK medical charities in 1999 and again in 2002. Its primary aim was to assess the commitment of these institutions towards funding research in complementary and alternative medicine (CAM). Sixty-two (1999) and 60 (2002) answers were received corresponding to response rates of 62% and 55%. The total CAM research funds have increased from pound 70,000 in 1999 to pound 412,755 in 2002. In terms of total research budgets, this amounts to 0.05% and 0.31%, respectively. The number of CAM research projects has increased but so has the number of charities who do not fund CAM research. We conclude from these data that CAM research funding by UK medical charities has increased. In relative terms it does, however, remain low and out of proportion to the prevalence of CAM use in the UK.

NMR Structure of the Integral Membrane Protein OmpX

Journal of Molecular Biology. Mar, 2004  |  Pubmed ID: 15037080

The structure of the integral membrane protein OmpX from Escherichia coli reconstituted in 60 kDa DHPC micelles (OmpX/DHPC) was calculated from 526 NOE upper limit distance constraints. The structure determination was based on complete sequence-specific assignments for the amide protons and the Val, Leu, and Ile(delta1) methyl groups in OmpX, which were selectively protonated on a perdeuterated background. The solution structure of OmpX in the DHPC micelles consists of a well-defined, eight-stranded antiparallel beta-barrel, with successive pairs of beta-strands connected by mobile loops. Several long-range NOEs observed outside of the transmembrane barrel characterize an extension of a four-stranded beta-sheet beyond the height of the barrel. This protruding beta-sheet is believed to be involved in intermolecular interactions responsible for the biological functions of OmpX. The present approach for de novo structure determination should be quite widely applicable to membrane proteins reconstituted in mixed micelles with overall molecular masses up to about 100 kDa, and may also provide a platform for additional functional studies.

Determination of the Absolute Chirality of Adsorbed Molecules

Angewandte Chemie (International Ed. in English). May, 2004  |  Pubmed ID: 15150767

Membrane Protein-lipid Interactions in Mixed Micelles Studied by NMR Spectroscopy with the Use of Paramagnetic Reagents

Chembiochem : a European Journal of Chemical Biology. Apr, 2004  |  Pubmed ID: 15185370

For solution NMR studies of the structure and function of membrane proteins, these macromolecules have to be reconstituted and solubilized in detergent micelles. Detailed characterization of the mixed detergent/protein micelles is then of key importance to validate the results from such studies, and to evaluate how faithfully the natural environment of the protein in the biological membrane is mimicked by the micelle. In this paper, a selection of paramagnetic probes with different physicochemical properties are used to characterize the 60 kDa mixed micelles consisting of about 90 molecules of the detergent dihexanoylphosphatidylcholine (DHPC) and one molecule of the Escherichia coli outer-membrane protein X (OmpX), which had previously been extensively studied by solution NMR techniques. The observation of highly selective relaxation effects on the NMR spectra of OmpX and DHPC from a water-soluble relaxation agent and from nitroxide spin labels attached to lipophilic molecules, confirmed data obtained previously with more complex NMR studies of the diamagnetic OmpX/DHPC system, and yielded additional novel insights into the protein-detergent interactions in the mixed micelles. The application of paramagnetic probes to the well-characterized OmpX/DHPC system indicates that such probes should be widely applicable as an efficient support of NMR studies of the topology of mixed membrane protein-detergent micelles.

NMR Structure of a Variant 434 Repressor DNA-binding Domain Devoid of Hydroxyl Groups

Journal of Biomolecular NMR. Jul, 2004  |  Pubmed ID: 15213439

Segmental Dystonia Induced by Wearing Glasses with a Ribbon: an Unusual Case of a Reverse Sensory Geste

Movement Disorders : Official Journal of the Movement Disorder Society. Aug, 2004  |  Pubmed ID: 15300666

Craniocervical muscles are the most frequently involved in dystonia, which can be either focal of segmental. While often experiencing an increase in dystonia with voluntary motor activity, many patients report temporary relief with geste antagoniste. We describe a patient who presented a peculiar craniocervical segmental dystonia, triggered by putting on glasses with a ribbon.

NMR Structures of Salt-refolded Forms of the 434-repressor DNA-binding Domain in 6 M Urea

Biochemistry. Nov, 2004  |  Pubmed ID: 15518542

The N-terminal 63-residue fragment of the phage 434-repressor, 434(1-63), has a well-defined globular fold in H(2)O solution, and is unfolded in 6 M urea at pH 7.5. In this study, 434(1-63) has been refolded by adding either 1.7 M NaCl or 0.47 M NaTFA to the solution in 6 M urea, and the NMR structures of both refolded forms have been determined. The two refolded forms have similar free energies of unfolding and are approximately 16 kJ/mol less stable than the protein in H(2)O solution. 434(1-63) refolded with NaCl exhibits NMR chemical shifts very similar to and a three-dimensional structure nearly identical to those of 434(1-63) in H(2)O solution. The protein refolded with NaTFA also has a similar global fold, but it shows local differences near Phe44, of which two different orientations of the aromatic ring are compatible with the experimental data. This local conformational polymorphism attracted our interest because hydrophobic contacts between two subdomains of residues 1-36 and 45-63 are mediated by the Phe44 side chain. Anion binding experiments suggest that this polymorphism is caused by binding of TFA(-) anions to a cluster of positively charged Arg and Lys residues located in the loop connecting the two subdomains, with apparent binding constants for TFA(-) (K(app)) on the order of 30 mM(-1).

Comparative Study on Two Freshwater Invertebrates for Monitoring Environmental Lead Exposure

Toxicology. May, 2005  |  Pubmed ID: 15804457

Two freshwater invertebrate organisms, Biomphalaria glabrata and Lumbriculus variegatus, were tested as potential experimental animal models to assess Pb exposure using acute laboratory bioassays. Since long, the enzyme delta-aminolevulinic acid dehydratase (ALA-D) has been recognised as a useful biomarker of Pb exposure and effect. Therefore, determinations of ALA-D activity were performed in the whole body soft tissues of pigmented and non-pigmented gastropods B. glabrata and in the oligochaete L. variegatus. The organisms were exposed to varying concentrations of Pb for 48 h. Levels of Pb in the invertebrates were also analysed. Highly significant negative correlations were found between the enzymatic activity and the levels of Pb exposure, and also between the enzymatic activity and the metal incorporated by the invertebrates. No significant differences were found in the enzyme activity nor in the resulting metal accumulation based on gastropod pigmentation. The values of Pb concentration that produce 50% of inhibition on the enzyme activity (EIC50) were 0.023 and 0.029 mg Pb/L for pigmented and non-pigmented B. glabrata, respectively. A much higher value was found for L. variegatus (0.703 mg Pb/L). The non-observed effect concentration (NOEC) on enzyme activity for the oligochaetes was 0.05 mg Pb/L, about twice the EIC50 calculated for the gastropods. These data showed that both pigmented and non-pigmented B. glabata were much more sensitive organisms than the oligochaetes. The differences in enzyme inhibition could be attributed, at least partly, to differences in the metal body burden found between the organisms, since levels of Pb accumulated by B. glabrata were approximately three times higher compared to those observed in L. variegatus. Therefore B. glabrata showed to be a more suitable and reliable bioindicator organism for assessing Pb contamination in aquatic ecosystems, especially at low levels of metal exposure.

NMR Techniques Used with Very Large Biological Macromolecules in Solution

Methods in Enzymology. 2005  |  Pubmed ID: 15808229

Methods for the characterization of very large biological macromolecules by NMR in solution are presented. For studies of molecular structures with molecular weights beyond 100,000 Da transverse relaxation in common multidimensional NMR experiments becomes a limiting factor. Novel techniques optimize transverse relaxation based on cross-correlated relaxation between dipole-dipole interactions and chemical shift anisotropy (CSA), and include transverse relaxation-optimized spectroscopy (TROSY), cross-correlated relaxation-enhanced polarization transfer (CRINEPT), and cross-correlated relaxation-induced polarization transfer (CRIPT). In combination with various biochemical isotope-labeling techniques these experimental schemes make possible studies of biological macromolecules with molecular masses of up to 1,000,000 Da by NMR in solution. The physical basis and the implementation of the experiments are discussed.

CAM Research in Britain: the Last 10 Years

Complementary Therapies in Clinical Practice. Feb, 2005  |  Pubmed ID: 15984219

Research into complementary and alternative medicine (CAM) is not as new as it might appear from a U.K. perspective. Most continental European countries have a long tradition in CAM research. Many studies of homoeopathy, for instance, were published decades ago in languages other than English [The trials of homeopathy. Origins, structure and development. Stiftung: Essen, Karl und Veronica Carstens, 2004]. However, it is probably true to say that, in the English speaking world and particularly in the U.K., CAM has become a respectable area of scientific investigation only during the last decade. In this article, we review the 10 years of CAM research in Britain.

Managing the Solvent Water Polarization to Obtain Improved NMR Spectra of Large Molecular Structures

Journal of Biomolecular NMR. May, 2005  |  Pubmed ID: 16041484

In large molecular structures, the magnetization of all hydrogen atoms in the solute is strongly coupled to the water magnetization through chemical exchange between solvent water and labile protons of macromolecular components, and through dipole-dipole interactions and the associated "spin diffusion" due to slow molecular tumbling. In NMR experiments with such systems, the extent of the water polarization is thus of utmost importance. This paper presents a formalism that describes the propagation of the water polarization during the course of different NMR experiments, and then compares the results of model calculations for optimized water polarization with experimental data. It thus demonstrates that NMR spectra of large molecular structures can be improved with the use of paramagnetic spin relaxation agents which selectively enhance the relaxation of water protons, so that a substantial gain in signal-to-noise can be achieved. The presently proposed use of a relaxation agent can also replace the water flip-back pulses when working with structures larger than about 30 kDa. This may be a valid alternative in situations where flip-back pulses are difficult to introduce into the overall experimental scheme, or where they would interfere with other requirements of the NMR experiment.

Automated Projection Spectroscopy (APSY)

Proceedings of the National Academy of Sciences of the United States of America. Aug, 2005  |  Pubmed ID: 16043707

This work presents the automated projection spectroscopy (APSY) method for the recording of discrete sets of j projections from N-dimensional (N > or = 3) NMR experiments at operator-selected projection angles and automatic identification of the correlation cross peaks. The result from APSY is the fully automated generation of the complete or nearly complete peak list for the N-dimensional NMR spectrum from a geometric analysis of the j experimentally recorded, low-dimensional projections. In the present implementation of APSY, two-dimensional projections of the N-dimensional spectrum are recorded by using techniques developed for projection-reconstruction spectroscopy [Kupce,E.& Freeman, R. (2004) J. Am. Chem. Soc. 126, 6429-6440]. All projections are peak-picked with the available automated routine atnos. The previously undescribed algorithm GAPRO (geometric analysis of projections) uses vector algebra to identify subgroups of peaks in different projections that arise from the same resonance in the N-dimensional spectrum, and from these subgroups it calculates the peak positions in the N-dimensional frequency space. Unambiguous identification thus can be achieved for all cross peaks that are not overlapped with other peaks in at least one of the N dimensions. Because of the correlation between the positions of corresponding peaks in multiple projections, uncorrelated noise is efficiently suppressed, so that APSY should be quite widely applicable for correlation spectra of biological macromolecules, which have intrinsically low peak density in the N-dimensional spectral space.

Direct NMR Observation of a Substrate Protein Bound to the Chaperonin GroEL

Proceedings of the National Academy of Sciences of the United States of America. Sep, 2005  |  Pubmed ID: 16116078

The reaction cycle and the major structural states of the molecular chaperone GroEL and its cochaperone, GroES, are well characterized. In contrast, very little is known about the nonnative states of the substrate polypeptide acted on by the chaperonin machinery. In this study, we investigated the substrate protein human dihydrofolate reductase (hDHFR) while bound to GroEL or to a single-ring analog, SR1, by NMR spectroscopy in solution under conditions where hDHFR was efficiently recovered as a folded, enzymatically active protein from the stable complexes upon addition of ATP and GroES. By using the NMR techniques of transverse relaxation-optimized spectroscopy (TROSY), cross-correlated relaxation-induced polarization transfer (CRIPT), and cross-correlated relaxation-enhanced polarization transfer (CRINEPT), bound hDHFR could be observed directly. Measurements of the buildup of hDHFR NMR signals by different magnetization transfer mechanisms were used to characterize the dynamic properties of the NMR-observable parts of the bound substrate. The NMR data suggest that the bound state includes random coil conformations devoid of stable native-like tertiary contacts and that the bound hDHFR might best be described as a dynamic ensemble of randomly structured conformers.

Ubiquitin-binding Domains in Y-family Polymerases Regulate Translesion Synthesis

Science (New York, N.Y.). Dec, 2005  |  Pubmed ID: 16357261

Translesion synthesis (TLS) is the major pathway by which mammalian cells replicate across DNA lesions. Upon DNA damage, ubiquitination of proliferating cell nuclear antigen (PCNA) induces bypass of the lesion by directing the replication machinery into the TLS pathway. Yet, how this modification is recognized and interpreted in the cell remains unclear. Here we describe the identification of two ubiquitin (Ub)-binding domains (UBM and UBZ), which are evolutionarily conserved in all Y-family TLS polymerases (pols). These domains are required for binding of poleta and poliota to ubiquitin, their accumulation in replication factories, and their interaction with monoubiquitinated PCNA. Moreover, the UBZ domain of poleta is essential to efficiently restore a normal response to ultraviolet irradiation in xeroderma pigmentosum variant (XP-V) fibroblasts. Our results indicate that Ub-binding domains of Y-family polymerases play crucial regulatory roles in TLS.

Effective Rotational Correlation Times of Proteins from NMR Relaxation Interference

Journal of Magnetic Resonance (San Diego, Calif. : 1997). Jan, 2006  |  Pubmed ID: 16188473

Knowledge of the effective rotational correlation times, tauc, for the modulation of anisotropic spin-spin interactions in macromolecules subject to Brownian motion in solution is of key interest for the practice of NMR spectroscopy in structural biology. The value of tauc enables an estimate of the NMR spin relaxation rates, and indicates possible aggregation of the macromolecular species. This paper reports a novel NMR pulse scheme, [15N,1H]-TRACT, which is based on transverse relaxation-optimized spectroscopy and permits to determine tauc for 15N-1H bonds without interference from dipole-dipole coupling of the amide proton with remote protons. [15N,1H]-TRACT is highly efficient since only a series of one-dimensional NMR spectra need to be recorded. Its use is suggested for a quick estimate of the rotational correlation time, to monitor sample quality and to determine optimal parameters for complex multidimensional NMR experiments. Practical applications are illustrated with the 110 kDa 7,8-dihydroneopterin aldolase from Staphylococcus aureus, the uniformly 15N-labeled Escherichia coli outer membrane protein X (OmpX) in 60 kDa mixed OmpX/DHPC micelles with approximately 90 molecules of unlabeled 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC), and the 16 kDa pheromone-binding protein from Bombyx mori, which cover a wide range of correlation times.

Effects of 5-aza-2'-deoxycytidine on Proliferation, Differentiation and P15/INK4b Regulation of Human Hematopoietic Progenitor Cells

Leukemia. Jan, 2006  |  Pubmed ID: 16307025

The demethylating agents 5-azacytidine and 5-aza-2'-deoxycytidine (DAC) have been shown to induce differentiation and inhibit growth of leukemic myeloid cells at low concentrations. However, the effect of DAC in changing the differentiation and proliferation behavior of normal human myeloid progenitors has rarely been investigated. Therefore, we established an in vitro model of normal hematopoietic differentiation, using CD34+ cells from mobilized peripheral blood, to study proliferation and colony formation, expression of several myeloid maturation markers and of the inhibitor of cyclin-dependent kinases p15/INK4b. Upon DAC treatment, cell growth was significantly decreased in a dose-dependent manner, without an increase in cytotoxicity. DAC treatment also resulted in a substantial increase of lysozyme-positive cells, which could be enhanced by G-CSF, a modest increase of myeloperoxidase+ and CD15+ cells, as well as an increase of colony-forming cells (CFU-GM) compared to control cells. p15/INK4b protein expression was strongly upregulated upon myeloid maturation, and additional DAC treatment did not change p15 expression or the methylation status of the p15 promoter at the noncytotoxic concentrations used. Taken together, these data indicate a role of DAC in changing myeloid progenitor cell expansion and differentiation. This model appears suitable also for global analyses of multiple differentially methylated genes.

NMR-derived Dynamic Aspects of N-type Inactivation of a Kv Channel Suggest a Transient Interaction with the T1 Domain

Biochemistry. Feb, 2006  |  Pubmed ID: 16460013

Some eukaryotic voltage-gated K+ (Kv) channels contain an N-terminal inactivation peptide (IP), which mediates a fast inactivation process that limits channel function during membrane depolarization and thus shapes the action potential. We obtained sequence-specific nuclear magnetic resonance (NMR) assignments for the polypeptide backbone of a tetrameric N-terminal fragment (amino acids 1-181) of the Aplysia Kv1.1 channel. Additional NMR measurements show that the tetramerization domain 1 (T1) has the same globular structure in solution as previously determined by crystallography and that the IP (residues 1-20) and the linker (residues 21-65) are in a flexibly disordered, predominantly extended conformation. A potential contact site between the T1 domain and the flexible tail (residues 1-65) has been identified on the basis of chemical-shift changes of individual T1 domain amino acids, which map to the T1 surface near the interface between adjacent subunits. Paramagnetic perturbation experiments further indicate that, in the ensemble of solution conformers, there is at least a small population of species with the IP localized in close proximity to the proposed interacting residues of the T1 tetramer. Electrophysiological measurements show that all three mutations in this pocket that we tested slow the rate of inactivation and speed up recovery, as predicted from the preinactivation site model. These results suggest that specific, short-lived transient interactions between the T1 domain and the IP or the linker segment may play a role in defining the regulatory kinetics of fast channel inactivation.

Chiral Recognition of Organic Molecules by Atomic Kinks on Surfaces

Physical Review Letters. Feb, 2006  |  Pubmed ID: 16486958

Two distinct non-mirror-symmetric conformations of D- and L-cysteine were found after adsorption on Au(17 11 9)S. This demonstrates chiral heterorecognition, i.e., enantioselectivity of S kinks on vicinal Au(111). The structures as determined by angle scanned x-ray photoelectron diffraction agree well with those from density functional theory calculations. The calculations predict adsorption energies of approximately 2 eV where D-cysteine binds 140 meV stronger than L-cysteine. The classical three point contact model for molecular recognition fails to explain these findings.

Measuring Protein Concentrations by NMR Spectroscopy

Journal of the American Chemical Society. Mar, 2006  |  Pubmed ID: 16492040

In applications of NMR to biological macromolecules in solution, the concentration of the NMR sample is an important parameter describing the sample and providing information for the selection and planning of experiments. Although concentrations can be measured directly by NMR spectroscopy, other methods are usually preferred to measure the concentration of macromolecules in NMR samples. The reasons are the difficulties in the correlation of the sample of interest with the signal intensity representing a known concentration. This correlation is usually obtained by adding to the sample a reference compound with known concentration and comparing the integral over resolved resonance lines of the molecules with known and unknown concentrations. For solutions of biological macromolecules it is very difficult to find a compound that does not interact with the macromolecules and has a resonance outside their spectral range. We introduce PULCON which is a method that correlates the absolute intensities of two spectra measured in different solution conditions. PULCON is easy to implement and apply on all NMR spectrometers; it does not need any special hardware or software. PULCON is very robust and at the same time delivers accurate concentrations of samples in the NMR tube. We demonstrate that PULCON has the potential to replace UV spectroscopy for concentration measurements of NMR samples.

[Neuronal Death and Growth Factors: New Therapeutic Approaches in Parkinson's Disease]

Revue Médicale Suisse. May, 2006  |  Pubmed ID: 16734187

Neurodegenerative disorders represent a major and growing cause of morbidity and mortality in our populations, and a therapeutic challenge for the years to come. This paper reviews the mechanisms implicated in neuronal death, focusing on the model of Parkinson's disease. Available data are critically presented, and oriented in a therapeutic perspective. Neuroprotective strategies are mentioned, along with stem cell transplantation, growth factor production and gene therapy.

Potential Use of Glycogen Level As Biomarker of Chemical Stress in Biomphalaria Glabrata

Toxicology. Jul, 2006  |  Pubmed ID: 16740351

Biomphalaria glabrata, a freshwater gastropod mollusc, was tested as biondicator organism to assess cadmium, lead and arsenic exposure using acute laboratory bioassays. Modifications of glycogen levels were measured in different anatomical regions of B. glabrata in order to test the usefulness of this parameter as a general biomarker of chemical stress. The snails were exposed 96 h to different concentrations of the following contaminants: 0.1 and 0.05 mg Cd/L; 0.5, 0.1 and 0.05 mg Pb/L; 0.5, 0.1 and 0.05 mg As/L. Significant decreases in the polysaccharide content were observed in gonadal region for all treated animals. Arsenic and lead at 0.1 and 0.5 mg/L level of exposure were also able to decrease the levels of glycogen in the pulmonary and digestive gland region. Glycogen content in the cephalopedal region of treated animals presented a significant decrease (p<0.05) when compared with control organisms only for arsenic at the highest level of exposure. To establish possible correlations between glycogen and contaminants accumulated by snails, analyses of the elements bioaccumulated in the different anatomical regions of B. glabrata were also performed. Cadmium and lead followed a similar pattern of bioaccumulation with highest values in the digestive gland region. Arsenic bioaccumulation, however, was highest in the gonadal region.

Automated Resonance Assignment of Proteins: 6D APSY-NMR

Journal of Biomolecular NMR. May, 2006  |  Pubmed ID: 16791738

The 6-dimensional (6D) APSY-seq-HNCOCANH NMR experiment correlates two sequentially neighboring amide moieties in proteins via the C' and Calpha nuclei, with efficient suppression of the back transfer from Calpha to the originating amide moiety. The automatic analysis of two-dimensional (2D) projections of this 6D experiment with the use of GAPRO (Hiller et al., 2005) provides a high-precision 6D peak list, which permits automated sequential assignments of proteins with the assignment software GARANT (Bartels et al., 1997). The procedure was applied to two proteins, the 63-residue 434-repressor(1-63) and the 115-residue TM1290. For both proteins, complete sequential assignments for all NMR-observable backbone resonances were obtained, and the polypeptide segments thus identified could be unambiguously located in the amino acid sequence. These results demonstrate that APSY-NMR spectroscopy in combination with a suitable assignment algorithm can provide fully automated sequence-specific backbone assignments of small proteins.

Bilateral Compressive Lumbosacral Plexopathy Due to Internal Iliac Artery Aneurysms

Journal of Neurology. Jun, 2006  |  Pubmed ID: 16807687

Concentration Measurements by PULCON Using X-filtered or 2D NMR Spectra

Magnetic Resonance in Chemistry : MRC. Jul, 2006  |  Pubmed ID: 16823904

Sample concentrations can be measured by nuclear magnetic resonance (NMR) spectroscopy without an internal reference compound using pulse length based concentration determination (PULCON) with 1D NMR spectra. PULCON delivers most accurate results if the spectrum of the sample of interest contains a resolved resonance; but can also be applied to spectral regions with overlapping resonances. If the exact number of lines contributing to the overlapping spectral region is not known, a corresponding error makes the result less precise. The uncertainty about the number of contributing resonances can be reduced with experiments that discriminate different classes of resonances by filtering techniques or by extending PULCON to two-dimensional NMR spectra. We demonstrate the application of PULCON with a 1D 15N-filtered experiment where aromatic resonances of a protein can be observed without interference from 15N-bound protons. Further, we extend PULCON to 2D NMR spectra that permits to determine the exact number of resonances. This extension can readily be applied with sample that contain different solutes.

Long-duration Response to Levodopa in Patients with Advanced Parkinson Disease Treated with Subthalamic Deep Brain Stimulation

Archives of Neurology. Jul, 2006  |  Pubmed ID: 16831963

Long-duration response (LDR) to levodopa is supposed to decrease with Parkinson disease (PD) progression, but direct observation of this response in advanced PD has never been performed.

Painful Hand and Moving Finger Treated by Wearing a Glove

Neurology. Aug, 2006  |  Pubmed ID: 16894112

The authors report a patient with unilateral painful hand and moving finger in whom tactile stimulation interrupted both the movement and the pain. This effect suggests a gating mechanism at a segmental level. The difference between afferent and efferent pathway levels and the delay of several months between trauma and occurrence of symptoms support a central mechanism, most probably involving sensorimotor reorganization at a segmental level.

Proton-proton Overhauser NMR Spectroscopy with Polypeptide Chains in Large Structures

Proceedings of the National Academy of Sciences of the United States of America. Oct, 2006  |  Pubmed ID: 17032756

The use of 1H-1H nuclear Overhauser effects (NOE) for structural studies of uniformly deuterated polypeptide chains in large structures is investigated by model calculations and NMR experiments. Detailed analysis of the evolution of the magnetization during 1H-1H NOE experiments under slow-motion conditions shows that the maximal 1H-1H NOE transfer is independent of the overall rotational correlation time, even in the presence of chemical exchange with the bulk water, provided that the mixing time is adjusted for the size of the structure studied. 1H-1H NOE buildup measurements were performed for the 472-kDa complex of the 72-kDa cochaperonin GroES with a 400-kDa single-ring variant of the chaperonin GroEL (SR1). These experiments demonstrate that multidimensional NOESY experiments with cross-correlated relaxation-enhanced polarization transfer and transverse relaxation-optimized spectroscopy elements can be applied to structures of molecular masses up to several hundred kilodaltabs, which opens new possibilities for studying functional interactions in large maromolecular assemblies in solution.

Complementary Therapies for Back Pain: is the Evidence Getting Stronger?

Clinical Rheumatology. May, 2007  |  Pubmed ID: 16941201

Back pain is the most common reason for using complementary therapies. This analysis of the trial evidence is aimed at determining whether the evidence base for or against complementary therapies for back pain is getting stronger. Two series of systematic reviews conducted with the same methodology 5 years apart were compared. The results suggest that the weight of the evidence has increased between 2000 and 2005 for a number of interventions. The direction of the evidence, however, remained unchanged for all but one therapy. We conclude that the value of complementary therapies in the management of back pain remains encouraging but not fully convincing.

Complementary/alternative Medicine for Supportive Cancer Care: Development of the Evidence-base

Supportive Care in Cancer : Official Journal of the Multinational Association of Supportive Care in Cancer. May, 2007  |  Pubmed ID: 17093910

The aim of this article is to compare the evidence relating to the effectiveness of complementary/alternative medicine (CAM) in palliative cancer care as it existed in 2000 and 2005.

Does Starvation Influence the Antioxidant Status of the Digestive Gland of Nacella Concinna in Experimental Conditions?

Comparative Biochemistry and Physiology. Toxicology & Pharmacology : CBP. Jul-Aug, 2007  |  Pubmed ID: 17196886

In a previous study we analysed the effect of diesel seawater contamination in the digestive gland of the Antarctic limpet Nacella concinna. We observed that antioxidant enzyme activities decreased after one-week starvation prior to the experiment, and this was considered in the analysis of the obtained results. To know whether the digestive gland oxidant-antioxidant status may be altered by starvation and experimental conditions, we evaluated the food deprivation effect in limpets from the nearshore shallow waters of Potter Cove, Antarctica. Organisms were acclimated to laboratory conditions and were divided in fed and starved groups, and maintained in these conditions during one month. Every week 20 limpets were sampled from each group. Digestive glands were dissected and kept frozen until they were processed. Superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) activities, as well as lipid peroxidation (LPO) measured as thiobarbituric reactive substances (TBARS), protein oxidation (PO) and reduced glutathione (GSH) were measured. For both groups of limpets, SOD increased its activity in the first week of the exposure period, with a maximum in the second week. CAT activity increased significantly in the second week, only for the starved group. Similarly, GST activity also increased for starved group in the second week; but maintained this tendency for both groups until the fourth week. In fed and starved limpets, TBARS values increased significantly, during the first week and then returned to normal values. The PO levels in the starved group increased only during the first week. The GSH content, for the fed group, increased significantly after the third week. The obtained results indicate that biochemical or physiological studies conducted with N. concinna should consider the effects of food deprivation and time spent under experimental conditions.

Acupuncture: Its Evidence-base is Changing

The American Journal of Chinese Medicine. 2007  |  Pubmed ID: 17265547

The effectiveness of acupuncture remains a controversial issue. The aim of this article is to evaluate trends over time in the development of the evidence-base of acupuncture. A comparison of two series of systematic reviews was conducted. The first related to the evidence-base in 2000, the second related to 2005. Both employed virtually the same methodology and criteria for evaluation. The results indicate that the evidence base has increased for 13 of the 26 conditions included in this comparison. For 7 indications it has become more positive (i.e. favoring acupuncture) and for 6 it had changed in the opposite direction. It is concluded, that acupuncture research is active. The emerging clinical evidence seems to imply that acupuncture is effective for some but not all conditions.

Quantification of Tremor and Bradykinesia in Parkinson's Disease Using a Novel Ambulatory Monitoring System

IEEE Transactions on Bio-medical Engineering. Feb, 2007  |  Pubmed ID: 17278588

An ambulatory system for quantification of tremor and bradykinesia in patients with Parkinson's disease (PD) is presented. To record movements of the upper extremities, a sensing units which included miniature gyroscopes, has been fixed to each of the forearms. An algorithm to detect and quantify tremor and another algorithm to quantify bradykinesia have been proposed and validated. Two clinical studies have been performed. In the first study, 10 PD patients and 10 control subjects participated in a 45-min protocol of 17 typical daily activities. The algorithm for tremor detection showed an overall sensitivity of 99.5% and a specificity of 94.2% in comparison to a video reference. The estimated tremor amplitude showed a high correlation to the Unified Parkinson's Disease Rating Scale (UPDRS) tremor subscore (e.g., r = 0.87, p < 0.001 for the roll axis). There was a high and significant correlation between the estimated bradykinesia related parameters estimated for the whole period of measurement and respective UPDRS subscore (e.g., r = -0.83, p < 0.001 for the roll axis). In the second study, movements of upper extremities of 11 PD patients were recorded for periods of 3-5 hr. The patients were moving freely during the measurements. The effects of selection of window size used to calculate tremor and bradykinesia related parameters on the correlation between UPDRS and these parameters were studied. By selecting a window similar to the period of the first study, similar correlations were obtained. Moreover, one of the bradykinesia related parameters showed significant correlation (r = -0.74, p < 0.01) to UPDRS with window sizes as short as 5 min. Our study provides evidence that objective, accurate and simultaneous assessment of tremor and bradykinesia can be achieved in free moving PD patients during their daily activities.

Real-time Imaging of the Spatial Distribution of Rf-heating in NMR Samples During Broadband Decoupling

Journal of Magnetic Resonance (San Diego, Calif. : 1997). Aug, 2007  |  Pubmed ID: 17507272

Continuous radio-frequency (rf) irradiation during decoupling and spin-lock periods in NMR pulse sequences may lead to undesired sample heating. Heat-sensitive samples can suffer damage from the sudden temperature rise which cannot be adequately compensated by the temperature control system. Moreover, as the heating is spatially inhomogeneous, higher temperature increases can arise locally than are indicated by the average increase detected by the temperature controller. In this work we present a technique that allows measurement of a real-time 2D-image of the temperature distribution inside an NMR sample during an experiment involving rf-heating. NMR imaging methods have previously been used to project the temperature distribution inside an NMR sample onto a single spatial axis or to acquire steady-state 2D- temperature distributions. The real-time 2D-temperature profiles obtained with our procedure provide much more detailed data. Our results show, that not only inhomogeneous heating but also inhomogeneous sample cooling contribute to the build-up of temperature gradients across the sample. The technique can be used to visualize rf-heating in order to protect sensitive samples and to experimentally test new coil geometries or to guide probehead design.

The Antioxidant Vitamins A, C, E and Selenium in the Treatment of Arthritis: a Systematic Review of Randomized Clinical Trials

Rheumatology (Oxford, England). Aug, 2007  |  Pubmed ID: 17522095

To systematically review the evidence from randomized clinical trials (RCTs) for the effectiveness of the antioxidant vitamins A, C, E or selenium or their combination in the treatment of arthritis. METHODSL: A systematic search of computerized databases from inception to September 2006 for relevant RCTs, application of pre-defined inclusion/exclusion criteria and independent data extraction by two authors. Methodological quality was assessed using the Jadad scale.

Sequence-specific Resonance Assignment of Soluble Nonglobular Proteins by 7D APSY-NMR Spectroscopy

Journal of the American Chemical Society. Sep, 2007  |  Pubmed ID: 17691781

Based on sequence-specific resonance assignments, NMR is the method of choice for obtaining atomic-resolution experimental data on soluble nonglobular proteins. So far, however, NMR assignment of unfolded polypeptides in solution has been a time-consuming task, mainly due to the small chemical shift dispersion, which has limited practical applications of the NMR approach. This paper presents an efficient, fully automated method for sequence-specific backbone and beta-carbon NMR assignment of soluble nonglobular proteins with sizes up to at least 150 residues. The procedure is based on new APSY (automated projection spectroscopy) experiments which benefit from the short effective rotational correlation times in soluble nonglobular polypeptides to record five- to seven-dimensional NMR data sets, which reliably resolves chemical shift degeneracies. Fully automated sequence-specific resonance assignments of the backbone nuclei and C(beta) are described for the uniformly (13)C,(15)N-labeled urea-denatured 148-residue outer membrane protein X (OmpX) from E. coli. The method is generally applicable to systems with similar spectroscopic properties as unfolded OmpX, and we anticipate that this paper may open the door for extensive atomic-resolution studies of chemical denaturant-unfolded proteins, as well as some classes of functional nonglobular polypeptides in solution.

Structure-function Analysis of the Endoplasmic Reticulum Oxidoreductase TMX3 Reveals Interdomain Stabilization of the N-terminal Redox-active Domain

The Journal of Biological Chemistry. Nov, 2007  |  Pubmed ID: 17881353

Disulfide bond formation in the endoplasmic reticulum is catalyzed by enzymes of the protein disulfide-isomerase family that harbor one or more thioredoxin-like domains. We recently discovered the transmembrane protein TMX3, a thiol-disulfide oxidoreductase of the protein disulfide-isomerase family. Here, we show that the endoplasmic reticulum-luminal region of TMX3 contains three thioredoxin-like domains, an N-terminal redox-active domain (named a) followed by two enzymatically inactive domains (b and b'). Using the recombinantly expressed TMX3 domain constructs a, ab, and abb', we compared structural stability and enzymatic properties. By structural and biophysical methods, we demonstrate that the reduced a domain has features typical of a globular folded domain that is, however, greatly destabilized upon oxidization. Importantly, interdomain stabilization by the b domain renders the a domain more resistant toward chemical denaturation and proteolysis in both the oxidized and reduced form. In combination with molecular modeling studies of TMX3 abb', the experimental results provide a new understanding of the relationship between the multidomain structure of TMX3 and its function as a redox enzyme. Overall, the data indicate that in addition to their role as substrate and co-factor binding domains, redox-inactive thioredoxin-like domains also function in stabilizing neighboring redox-active domains.

Characterization of in Vitro Growth of Multiple Myeloma Cells

Experimental Hematology. Oct, 2007  |  Pubmed ID: 17889722

To develop an in vitro culture system for rapid assessment of multiple myeloma (MM) cell growth.

Mind-body Therapies: Are the Trial Data Getting Stronger?

Alternative Therapies in Health and Medicine. Sep-Oct, 2007  |  Pubmed ID: 17900044

The effectiveness of mind-body therapies is sometimes doubted. The aim of this article is to evaluate trends in the development of the evidence base for autogenic training, hypnotherapy, and relaxation therapy. For this purpose, a comparison of 2 series of systematic reviews was conducted. The first is related to the evidence base in 2000, the second to that in 2005. Both employed virtually the same methodology and criteria for evaluation. The results of our comparisons show considerable changes during the observation period. The weight of the evidence has become stronger for several indications, and the direction of the evidence has been altered in a positive sense in several conditions. Applying the rules of evidence-based medicine, the following mind-body therapies are now supported by strong evidence: hypnotherapy for labor pain and relaxation therapy for anxiety and insomnia, as well as for nausea and vomiting induced by chemotherapy. It is concluded that an evidence-based approach for mind-body therapies is constructive and can generate positive results.

Clinical Genetics of Parkinson's Disease and Related Disorders

Parkinsonism & Related Disorders. 2007  |  Pubmed ID: 18267241

Our knowledge regarding the genetics of Parkinson's disease (PD) and parkinsonism has evolved dramatically during the past decade, with the discovery of numerous loci and genes. The LRRK2 gene has emerged as the most commonly involved in both familial and sporadic PD. Several variants in LRRK2 and SNCA have been associated with an increased risk of sporadic PD. PRKN, PINK1 and DJ1 mutations cause early-onset recessively inherited PD. Autosomal dominant dementia and parkinsonism is caused by mutations in the MAPT gene, and in the most recently discovered PGRN gene.

Study of a Swiss Dopa-responsive Dystonia Family with a Deletion in GCH1: Redefining DYT14 As DYT5

Neurology. Apr, 2008  |  Pubmed ID: 17804835

To report the study of a multigenerational Swiss family with dopa-responsive dystonia (DRD).

Long-term Outcome of 50 Consecutive Parkinson's Disease Patients Treated with Subthalamic Deep Brain Stimulation

Parkinsonism & Related Disorders. 2008  |  Pubmed ID: 17822940

To describe the long-term outcome in 50 consecutive advanced Parkinson's disease (PD) patients treated with subthalamic nucleus deep brain stimulation (STN-DBS).

Rapidly Progressive Familial Parkinsonism with Central Hypoventilation, Depression and Weight Loss (Perry Syndrome)--a Literature Review

Parkinsonism & Related Disorders. 2008  |  Pubmed ID: 17870652

Autosomal dominant parkinsonism, hypoventilation, depression and weight loss (Perry syndrome) has been reported in only seven families worldwide. It is a rapidly progressive disease leading to death from respiratory insufficiency within a few years. Parkinsonism is usually mild, with bradykinesia, rigidity, rest and postural tremor, and axial signs. Response to levodopa is poor although transient response has been occasionally observed. The early signs include parkinsonism, depression and weight loss, whereas hypoventilation is a late feature. Neuropathology shows severe neuronal loss in the substantia nigra, less prominent neuronal loss in the locus coeruleus, and no or few Lewy bodies. In this review, we also propose diagnostic criteria for this condition.

Interactions with Hydrophobic Clusters in the Urea-unfolded Membrane Protein OmpX

Angewandte Chemie (International Ed. in English). 2008  |  Pubmed ID: 18161715

Program Strategies for Adolescent Smoking Cessation

The Journal of School Nursing : the Official Publication of the National Association of School Nurses. Feb, 2008  |  Pubmed ID: 18220452

School nurses who work with adolescents are in an ideal position to promote smoking cessation. This opportunity is important because research suggests teens who smoke are likely to become habitual smokers. This study characterizes adolescents' patterns and levels of smoking, describes adolescents' perceptions toward smoking, and delineates quit strategies that may prove helpful for adolescents who attempt smoking cessation. Results suggest adolescent smokers have highly variable patterns and levels of smoking. They fail to consider their future health and continue to be unaware of the harmful effects of smoking and the addictive nature of tobacco. Among adolescent smokers, there are few gender differences in perception of smoking. Therefore, gender specific cessation programs may not be necessary. The most effective quit strategy was the acquisition of information on contents of cigarettes and the health effects of smoking. Armed with these strategies, school nurses can provide leadership in the design and implementation of school based smoking cessation programs.

Projected [(1)H, (15)N]-HMQC-[ (1)H, (1)H]-NOESY for Large Molecular Systems: Application to a 121 KDa Protein-DNA Complex

Journal of Biomolecular NMR. Mar, 2008  |  Pubmed ID: 18231863

We present a projected [(1)H,(15)N]-HMQC-[(1)H,(1)H]-NOESY experiment for observation of NOE interactions between amide protons with degenerate (15)N chemical shifts in large molecular systems. The projection is achieved by simultaneous evolution of the multiple quantum coherence of the nitrogen spin and the attached proton spin. In this way NOE signals can be separated from direct-correlation peaks also in spectra with low resolution by fully exploiting both (1)H and (15)N frequency differences, such that sensitivity can be increased by using short maximum evolution times. The sensitivity of the experiment is not dependent on the projection angle for projections up to 45 degrees and no additional pulses or delays are required as compared to the conventional 2D [(1)H,(15)N]-HMQC-NOESY. The experiment provides two distinct 2D spectra corresponding to the positive and negative angle projections, respectively. With a linear combination of 1D cross-sections from the two projections the unavoidable sensitivity loss in projection spectra can be compensated for each particular NOE interaction. We demonstrate the application of the novel projection experiment for the observation of an NOE interaction between two sequential glycines with degenerate (15)N chemical shifts in a 121.3 kDa complex of the linker H1 histone protein with a 152 bp linear DNA.

Etiology and Pathophysiology of Frontotemporal Dementia, Parkinson Disease and Alzheimer Disease: Lessons from Genetic Studies

Neuro-degenerative Diseases. 2008  |  Pubmed ID: 18322368

Genetic studies have led to major discoveries in the pathogenesis of various neurodegenerative diseases. Ubiquitin-positive familial frontotemporal dementia was recently found to be caused by mutations in the progranulin gene (PGRN), and the major constituent of the inclusions, TDP-43, was subsequently identified. The tau gene (MAPT) causes frontotemporal dementia with parkinsonism linked to chromosome 17. In Parkinson disease, LRRK2 mutations have emerged as a major cause of both familial and sporadic forms, adding to the previously known genes SNCA,PRKN,DJ1 and PINK1. Several genes have been implicated in Alzheimer disease, including the APP gene and the PSEN genes. Recently, variants in the sortilin-related receptor 1 gene, SORL1, were associated with Alzheimer disease.

Autosomal Dominant Dopa-responsive Parkinsonism in a Multigenerational Swiss Family

Parkinsonism & Related Disorders. Aug, 2008  |  Pubmed ID: 18342564

To describe a large family with autosomal dominant parkinsonism.

Progranulin Gene Mutation with an Unusual Clinical and Neuropathologic Presentation

Movement Disorders : Official Journal of the Movement Disorder Society. Jun, 2008  |  Pubmed ID: 18442119

Progranulin gene (PGRN) mutations cause frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U). Patients usually present with a frontotemporal dementia syndrome and have prominent atrophy and neuronal loss in frontal and temporal cortices and the striatum, with neuronal intranuclear and cytoplasmic inclusions. Clinical, neuropathological, and genetic studies are reported on an individual with PGRN mutation and her family members. We describe a patient with a PGRN c.26C>A mutation who presented with progressive stuttering dysarthria, oculomotor abnormalities, choreic buccolingual movements, and mild parkinsonism. Two other family members were affected, one with a behavioral variant frontotemporal dementia syndrome, the other with a diagnosis of probable Alzheimer's disease. At autopsy there was no neuronal loss in the cortex or medial temporal lobe structures, but there was striatal gliosis. Immunohistochemistry for ubiquitin and TDP-43 revealed neuronal cytoplasmic and intranuclear inclusions as well as neurites. This study further expands the clinical and pathological spectrum of PGRN mutations, and suggests the diagnosis could be missed in some individuals with atypical presentations.

Automated NMR Assignment of Protein Side Chain Resonances Using Automated Projection Spectroscopy (APSY)

Journal of the American Chemical Society. Sep, 2008  |  Pubmed ID: 18710239

This paper describes an automated method for sequence-specific NMR assignment of the aliphatic resonances of protein side chains in small- and medium-sized globular proteins in aqueous solution. The method requires the recording of a five-dimensional (5D) automated projection spectroscopy (APSY-) NMR experiment and the subsequent analysis of the APSY peak list with the algorithm ALASCA (Algorithm for local and linear assignment of side chains from APSY data). The 5D APSY-HC(CC-TOCSY)CONH experiment yields 5D chemical shift correlations of aliphatic side chain C-H moieties with the backbone atoms H(N), N, and C'. A simultaneous variation of the TOCSY mixing times and the projection angles in this APSY-type TOCSY experiment gives access to all aliphatic C-H moieties in the 20 proteinogenic amino acids. The correlation peak list resulting from the 5D APSY-HC(CC-TOCSY)CONH experiment together with the backbone assignment of the protein under study is the sole input for the algorithm ALASCA that assigns carbon and proton resonances of protein side chains. The algorithm is described, and it is shown that the aliphatic parts of 17 of the 20 common amino acid side chains are assigned unambiguously, whereas the remaining three amino acids are assigned with a certainty of above 95%. The overall feasibility of the approach is demonstrated with the globular 116-residue protein TM1290, for which reference assignments are known. For this protein, 97% of the expected side chain carbon atoms and 87% of the expected side chain protons were detected with the 5D APSY-HC(CC-TOCSY)CONH experiment in 24 h of spectrometer time, and all these resonances were correctly assigned by ALASCA. Based on the experience with TM1290, we expect that the approach presented in this work is routinely applicable to globular proteins with sizes up to at least 120 amino acids.

Insights into the Dynamics of Hereditary Diffuse Leukoencephalopathy with Axonal Spheroids

Neurology. Sep, 2008  |  Pubmed ID: 18794495

To report a new American family with hereditary diffuse leukoencephalopathy with spheroids (HDLS), including serial, presymptomatic and symptomatic, cranial MRIs from the proband.

APSY-NMR with Proteins: Practical Aspects and Backbone Assignment

Journal of Biomolecular NMR. Nov, 2008  |  Pubmed ID: 18841481

Automated projection spectroscopy (APSY) is an NMR technique for the recording of discrete sets of projection spectra from higher-dimensional NMR experiments, with automatic identification of the multidimensional chemical shift correlations by the dedicated algorithm GAPRO. This paper presents technical details for optimizing the set-up and the analysis of APSY-NMR experiments with proteins. Since experience so far indicates that the sensitivity for signal detection may become the principal limiting factor for applications with larger proteins or more dilute samples, we performed an APSY-NMR experiment at the limit of sensitivity, and then investigated the effects of varying selected experimental parameters. To obtain the desired reference data, a 4D APSY-HNCOCA experiment with a 12-kDa protein was recorded in 13 min. Based on the analysis of this data set and on general considerations, expressions for the sensitivity of APSY-NMR experiments have been generated to guide the selection of the projection angles, the calculation of the sweep widths, and the choice of other acquisition and processing parameters. In addition, a new peak picking routine and a new validation tool for the final result of the GAPRO spectral analysis are introduced. In continuation of previous reports on the use of APSY-NMR for sequence-specific resonance assignment of proteins, we present the results of a systematic search for suitable combinations of a minimal number of four- and five-dimensional APSY-NMR experiments that can provide the input for algorithms that generate automated protein backbone assignments.

Pallidonigral TDP-43 Pathology in Perry Syndrome

Parkinsonism & Related Disorders. May, 2009  |  Pubmed ID: 18723384

Autosomal dominant parkinsonism, hypoventilation, depression and severe weight loss (Perry syndrome) is an early-onset rapidly progressive disease. At autopsy, previous studies have found severe neuronal loss in the substantia nigra without Lewy bodies. Transactive response DNA-binding protein of 43 kDa (TDP-43) has recently been identified as a major ubiquitinated constituent of neuronal and glial inclusions in frontotemporal lobar degeneration with ubiquitin-positive inclusions and in amyotrophic lateral sclerosis. This study reports clinical, genetic and neuropathologic investigations of Perry syndrome.

Movement Disorders: Insights into Mechanisms and Hopes for Treatment

Lancet Neurology. Jan, 2009  |  Pubmed ID: 19081502

Effect of Cadmium, Lead and Arsenic on the Oviposition, Hatching and Embryonic Survival of Biomphalaria Glabrata

The Science of the Total Environment. Mar, 2009  |  Pubmed ID: 19108873

Biomphalaria glabrata is a widespread freshwater gastropod mollusc. The easy aquaculture of these organisms allow its use as an accessible tool for contamination bioassays. B. glabrata showed marked metabolic responses when exposed to cadmium, lead and arsenic. Those responses could also affect the reproduction of the snails. Taking into account this hypothesis, B. glabrata were exposed for 96 h (acute laboratory bioassays) to different concentrations of cadmium (0.1, 0.05 and 0 mg/L), lead (0.5, 0.1, 0.05 and 0 mg/L) and arsenic (0.5, 0.1, 0.05 and 0 mg/L). Snails were removed from the aquaria while eggs were left in the same contaminant concentrations. The effect of the assayed toxicants on snail reproduction was registered as the alterations of the total number of laid eggs (TNLE), hatching time and embryonic survival. At 0.10 mg/L cadmium significantly decreased the TNLE (p<0.05) and no embryos survived. The lowest assayed level (0.05 mg/L) of cadmium, delayed the hatching time twice when it was compared with the control group (p<0.01). Lead decreased the TNLE at 0.5 mg/L level (p<0.01). The other assayed doses (0.05 and 0.10 mg/L) also decreased embryonic survival significantly (p<0.05 and p<0.01 respectively) and extended twice the time to hatching (p<0.01). The 0.50 mg/L level killed all embryos. Arsenic at all studied concentrations decreased the TNLE (p<0.05) while the hatching time was increased by 50%. Embryo survival only decreased at the highest level (0.5 mg/L) of arsenic assayed. In summary, the acute exposure (96 h) to cadmium lead and arsenic, altered the reproduction of B. glabrata, modifying the TNLE, hatching time and embryonic survival.

FGF20 and Parkinson's Disease: No Evidence of Association or Pathogenicity Via Alpha-synuclein Expression

Movement Disorders : Official Journal of the Movement Disorder Society. Feb, 2009  |  Pubmed ID: 19133659

Genetic variation in fibroblast growth factor 20 (FGF20) has been associated with risk of Parkinson's disease (PD). Functional evidence suggested the T allele of one SNP, rs12720208 C/T, altered PD risk by increasing FGF20 and alpha-synuclein protein levels. Herein we report our association study of FGF20 and PD risk in four patient-control series (total: 1,262 patients and 1,881 controls), and measurements of FGF20 and alpha-synuclein protein levels in brain samples (nine patients). We found no evidence of association between FGF20 variability and PD risk, and no relationship between the rs12720208 genotype, FGF20 and alpha-synuclein protein levels.

DCTN1 Mutations in Perry Syndrome

Nature Genetics. Feb, 2009  |  Pubmed ID: 19136952

Perry syndrome consists of early-onset parkinsonism, depression, severe weight loss and hypoventilation, with brain pathology characterized by TDP-43 immunostaining. We carried out genome-wide linkage analysis and identified five disease-segregating mutations affecting the CAP-Gly domain of dynactin (encoded by DCTN1) in eight families with Perry syndrome; these mutations diminish microtubule binding and lead to intracytoplasmic inclusions. Our findings show that DCTN1 mutations, previously associated with motor neuron disease, can underlie the selective vulnerability of other neuronal populations in distinct neurodegenerative disorders.

Familial Idiopathic Basal Ganglia Calcification: a Challenging Clinical-pathological Correlation

Journal of Neurology. May, 2009  |  Pubmed ID: 19252803

The Complementation of Yeast with Human or Plasmodium Falciparum Hsp90 Confers Differential Inhibitor Sensitivities

Molecular and Biochemical Parasitology. Apr, 2009  |  Pubmed ID: 19320098

Developing novel drugs against the unicellular parasite Plasmodium is complicated by the paucity of simple screening systems. Heat-shock proteins are an essential class of proteins for the parasite's cyclical life style between different cellular milieus and temperatures. The molecular chaperone Hsp90 assists a large variety of proteins, but its supporting functions for many proteins that are important for cancer have made it into a well-studied drug target. With a better understanding of the differences between Hsp90 and of the malarial parasite and Hsp90 of its human host, new therapeutic options might become available. We have generated a set of isogenic strains of the budding yeast Saccharomyces cerevisiae where the essential yeast Hsp90 proteins have been replaced with either of the two human cytosolic isoforms Hsp90alpha or Hsp90beta, or with Hsp90 from Plasmodium falciparum (Pf). All strains express large amounts of the Flag-tagged Hsp90 proteins and are viable. Even though the strain with Pf Hsp90 grows more poorly, it provides a tool to reconstitute additional aspects of the parasite Hsp90 complex and its interactions with substrates in yeast as a living test tube. Upon exposure of the set of Hsp90 test strains to the two Hsp90 inhibitors radicicol (Rd) and geldanamycin (GA), we found that the strain with Pf Hsp90 is relatively more sensitive to GA than to Rd compared to the strains with human Hsp90's. This indicates that this set of yeast strains could be used to screen for new Pf Hsp90 inhibitors with a wider therapeutic window.

[Alternative Diagnostic Methods]

MMW Fortschritte Der Medizin. Jan, 2009  |  Pubmed ID: 19391395

Phactr2 and Parkinson's Disease

Neuroscience Letters. Mar, 2009  |  Pubmed ID: 19429005

Attempts at replicating the first genome-wide association study (GWAS) in Parkinson's disease (PD) have not successfully identified genetic risk factors. The present study reevaluates data from the first GWAS and focuses on the SNP (rs11155313, located in the Phactr2 gene) with the lowest P-value in the Tier 2 patient-control series. We employed four case-control series to examine the nominated SNP rs11155313 and identified association in US (OR: 1.39, P=0.032), Canadian (OR: 1.41, P=0.014) and Irish (OR: 1.44, P=0.034) patient-control series, but not in the Norwegian series (OR: 1.15, P=0.27). When combining all four series the observed trend was statistically significant (OR: 1.30, P<0.001). This study shows that reappraisal of publicly available results of GWAS may help nominate new risk factors for PD.

GRN 3'UTR+78 C>T is Not Associated with Risk for Parkinson's Disease

European Journal of Neurology : the Official Journal of the European Federation of Neurological Societies. Aug, 2009  |  Pubmed ID: 19473366

A single nucleotide polymorphism in the 3'-untranslated region of the progranulin gene (GRN; 3'UTR+78C>T; rs5848) was reported to alter the risk for frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U). rs5848 is located within a micro-RNA binding site and affects the expression of GRN.

Leukoencephalopathy with Spheroids (HDLS) and Pigmentary Leukodystrophy (POLD): a Single Entity?

Neurology. Jun, 2009  |  Pubmed ID: 19487654

Hereditary diffuse leukoencephalopathy with axonal spheroids (HDLS) and familial pigmentary orthochromatic leukodystrophy (POLD) present as adult-onset dementia with motor impairment and epilepsy. They are regarded as distinct diseases. We review data from the literature that support their being a single entity. Apart from a slightly older age at onset, a more rapid course, and more prominent pyramidal tract involvement, familial POLD is clinically similar to HDLS. Moreover, the pathologic hallmarks of the two diseases, axonal spheroids in HDLS and pigmented macrophages in POLD, can be identified in both conditions. This supports HDLS and POLD being referred collectively as adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP).

Characterization of DCTN1 Genetic Variability in Neurodegeneration

Neurology. Jun, 2009  |  Pubmed ID: 19506225

Recently, mutations in DCTN1 were found to cause Perry syndrome, a parkinsonian disorder with TDP-43-positive pathology. Previously, mutations in DCTN1 were identified in a family with lower motor neuron disease, in amyotrophic lateral sclerosis (ALS), and in a family with ALS/frontotemporal dementia (FTD), suggesting a central role for DCTN1 in neurodegeneration.

GCH1 Expression in Human Cerebellum from Healthy Individuals is Not Gender Dependent

Neuroscience Letters. Oct, 2009  |  Pubmed ID: 19573577

Dopa-responsive dystonia (DRD) is a familial childhood-onset disease characterized by fluctuating dystonia, associated with tremor and parkinsonism in some patients. In most families the disease displays autosomal dominant inheritance due to mutations in the GTP cyclohydrolase 1 gene (GCH1). Penetrance and symptom severity display strong female predominance for which gender-specific GCH1 expression has been hypothesized. In this study, GCH1 mRNA expression was measured in cerebellar tissue from 66 healthy human subjects (30 women), and in cerebellar and nigral tissue from eight individuals. No significant difference was found between men and women with small effect sizes observed. Although the correlation between cerebellar and nigral GCH1 expression remains to be further examined, this exploratory study does not support gender-specific GCH1 expression being the basis for the skewed gender distribution observed in DRD patients.

Serenoa Repens (saw Palmetto): a Systematic Review of Adverse Events

Drug Safety : an International Journal of Medical Toxicology and Drug Experience. 2009  |  Pubmed ID: 19591529

Serenoa repens (W. Bartram) Small, also known as saw palmetto, is one of the most widely used herbal preparations for the treatment of lower urinary tract symptoms (LUTS) and benign prostatic hyperplasia (BPH). Although a number of randomized controlled trials (RCTs) and systematic reviews of the efficacy of S. repens for the treatment of LUTS and BPH have been published, no systematic review on its drug interactions or adverse events currently exists. This review assesses all available human safety data of S. repens monopreparations. Systematic literature searches were conducted from date of inception to February 2008 in five electronic databases; reference lists and our departmental files were checked for further relevant publications. Information was requested from spontaneous reporting schemes of the WHO and national safety bodies. Twenty-four manufacturers/distributors of S. repens preparations and four herbalist organizations were contacted for additional information. No language restrictions were imposed. Only reports of adverse events in humans from monopreparations of S. repens were included. Data from all articles, regardless of study design, reporting adverse events or interactions were independently extracted by the first author and validated by the second. Forty articles (26 randomized controlled trials, 4 non-randomized controlled trials, 6 uncontrolled trials and 4 case reports/series) were included. They suggest that adverse events associated with the use of S. repens are mild and similar to those with placebo. The most frequently reported adverse events are abdominal pain, diarrhoea, nausea, fatigue, headache, decreased libido and rhinitis. More serious adverse events such as death and cerebral haemorrhage are reported in isolated case reports and data from spontaneous reporting schemes, but causality is questionable. No drug interactions were reported. Currently available data suggest that S. repens is well tolerated by most users and is not associated with serious adverse events. The majority of adverse events are mild, infrequent and reversible, and include abdominal pain, diarrhoea, nausea and fatigue, headache, decreased libido and rhinitis. We found no evidence for drug interactions with S. repens. However, higher quality reporting of adverse events is essential if safety assessments are to be improved in future.

1H, 15N, 13C Resonance Assignment of the Acyl Carrier Protein Subunit of the Saccharomyces Cerevisiae Fatty Acid Synthase

Biomolecular NMR Assignments. Jun, 2009  |  Pubmed ID: 19636964

Acyl carrier proteins participate in the synthesis of fatty acids. Here we report the NMR resonances assignment of the acyl carrier protein domain of the Saccharomyces cerevisiae fatty acid synthase which corresponds to the fragment 138A-302L in the primary structure. The assignment will allow performing NMR studies with the aim to investigate the intrinsic dynamics of this protein, and to study the structural changes upon apo-holo transformation in order to unveil the mechanism of binding of the growing acyl chain.

Coping Strategies Help Women Facing Economic Stress

Dermatology Nursing / Dermatology Nurses' Association. Jul-Aug, 2009  |  Pubmed ID: 19694063

GCH1 in Early-onset Parkinson's Disease

Movement Disorders : Official Journal of the Movement Disorder Society. Oct, 2009  |  Pubmed ID: 19735094

Mutations in GTP-cyclohydrolase 1 (GCH1) cause autosomal dominant dopa-responsive dystonia (DRD), characterized by childhood-onset foot dystonia that later generalizes. DRD patients frequently present with associated Parkinsonism. Conversely, early-onset Parkinson's disease (EOPD) patients commonly display dystonia. Herein, we investigated the frequency of GCH1 mutations in a series of 53 familial EOPD patients (21 with dystonia) and screened them for mutations in PRKN, PINK1, and DJ-1. In addition, we examined a matched EOPD patient-control series for association of common variability at the GCH1 locus and EOPD susceptibility. No GCH1 coding change or copy-number abnormality was identified in familial EOPD patients. A novel 18-bp deletion was found in the proximal promoter (two patients, one control), which is expected to knock out two regulatory elements previously shown to regulate GCH1 transcription. No association was found between GCH1 variability and risk of EOPD. Fourteen (26.4%) familial EOPD patients had homozygous or compound heterozygous PRKN mutations. PRKN-positive patients were 10 years younger than PRKN-negative patients and had a twofold higher prevalence of dystonia. This study does not support a significant role for genetic variation at the GCH1 locus in EOPD. However, our results further highlight the relevance of PRKN screening in familial EOPD.

Artichoke Leaf Extract for Treating Hypercholesterolaemia

Cochrane Database of Systematic Reviews (Online). 2009  |  Pubmed ID: 19821306

Hypercholesterolaemia is directly associated with an increased risk for coronary heart disease and other sequelae of atherosclerosis. Artichoke leaf extract (ALE) has been implicated in lowering cholesterol levels. Whether ALE is truly effective for this indication, however, is still a matter of debate.

Conducting Systematic Reviews of Complementary and Alternative Medicine: Common Pitfalls

Evaluation & the Health Professions. Dec, 2009  |  Pubmed ID: 19942632

Systematic reviews (SRs) are considered the best tools for summarizing the evidence for or against the effectiveness of health care interventions. The principles and methods of SRs apply equally to both, mainstream and complementary/alternative medicine (CAM). Certain challenges are, however, more commonly encountered in CAM or even specific to it; this article is aimed at raising awareness of these among systematic reviewers. When searching for literature, specific issues relating to specialist databases, indexing, access, foreign language studies, and certain forms of publication bias need to be considered. Researchers also need to be aware of the difficulties of comparing CAM studies and address the variability between studies. CAM modalities are highly diversified and great variations exist in the standardization of herbal products and other dietary supplements. Individualization of treatment as well as different classifications of disease and different diagnostic methods need to be addressed. Expectation bias is high in CAM, and finding appropriate controls and blinding are often challenging. It is important that these issues are taken into account early on in the planning stages of an SR so that proper consideration can be given to the search strategies, inclusion/exclusion criteria and methods of analysis with the overall aim of reducing bias.

Calbindin-1 Association and Parkinson's Disease

European Journal of Neurology : the Official Journal of the European Federation of Neurological Societies. Feb, 2010  |  Pubmed ID: 19674066

Calcium levels have been proposed to play an important role in the selective vulnerability of nigrostriatal dopaminergic neurons in Parkinson's disease (PD). Recently, an association was reported between the calcium buffer, calbindin (rs1805874) and risk of PD in a Japanese patient-control series.

LINGO1 Rs9652490 is Associated with Essential Tremor and Parkinson Disease

Parkinsonism & Related Disorders. Feb, 2010  |  Pubmed ID: 19720553

Recently, a variant in LINGO1 (rs9652490) was found to associate with increased risk of essential tremor. We set out to replicate this association in an independent case-control series of essential tremor from North America. In addition, given the clinical and pathological overlap between essential tremor and Parkinson disease, we also evaluate the effect of LINGO1 rs9652490 in two case-control series of Parkinson disease. Our study demonstrates a significant association between LINGO1 rs9652490 and essential tremor (P = 0.014) and Parkinson disease (P = 0.0003), thus providing the first evidence of a genetic link between both diseases.

A Comparative Study of LRRK2, PINK1 and Genetically Undefined Familial Parkinson's Disease

Journal of Neurology, Neurosurgery, and Psychiatry. Apr, 2010  |  Pubmed ID: 19726410

Genetic classification of Parkinson's disease (PD) subtypes may become the preferred diagnostic tool for neurologists. Herein we compare clinical features from a large cohort of patients with familial PD of unknown aetiology or attributable to distinct genetic forms. Comprehensive neurological examinations were performed in 231 familial PD patients from Tunisia. Analysis was previously performed to screen for mutations in leucine rich repeat kinase 2 (LRRK2), PTEN induced kinase 1 (PINK1) and parkin (PRKN). Clinical features were compared between patients with genetically undefined PD (n=107) and those with LRRK2 (n=73) and PINK1 (n=42) mutations using regression analyses adjusted for gender, age of onset and disease duration. PRKN cases (n=9) were too few for meaningful statistical analysis. In comparison with genetically undefined patients, LRRK2 mutation carriers had more severe motor symptoms (median Unified Parkinson's Disease Rating Scale scores approximately 1.6 times higher, p<0.001), a higher rate of dyskinesia (OR 4.21, p=0.002) and use of dopamine agonists (OR 3.64, p<0.001), and less postural tremor (OR 0.21, p<0.001). PINK1 mutation carriers presented an increased rate of drug induced dyskinesia (OR 3.81, p=0.007) and a lower rate of postural tremor (OR 0.16, p<0.001) than genetically undefined patients. As expected, PINK1 patients had younger ages and ages at disease onset, and a longer disease duration compared with LRRK2 mutation carriers and genetically undefined patients. Clinical differences between LRRK2, PINK1 and genetically undefined familial PD appear more pronounced than previously appreciated, and may prove useful in clinical practice. As future therapies are targeted to specific protein abnormalities, identifying the genetic causes and associated clinical and pathological features will determine diagnosis, preventative medicine and drug intervention strategies.

Elucidating the Genetics and Pathology of Perry Syndrome

Journal of the Neurological Sciences. Feb, 2010  |  Pubmed ID: 19732908

Perry syndrome is characterized clinically by autosomal dominantly inherited, rapidly progressive parkinsonism, depression, weight loss and hypoventilation. In the seven families reported previously and the two new families presented herein (the Hawaii family and the Fukuoka-4 Japanese family), the mean disease onset age is 48 years (range: 35-61) and the mean disease duration five years (range: 2-10). Histology and immunohistochemistry show severe neuronal loss in the substantia nigra and locus coeruleus, with TDP-43-positive pathology in neurons (intranuclear and cytoplasmic inclusions, dystrophic neurites, axonal spheroids) and glial cells (glial cytoplasmic inclusions). Compared with other TDP-43-proteinopathies (amyotrophic lateral sclerosis and ubiquitin-positive frontotemporal lobar degeneration), the distribution is unique in Perry syndrome with pallidonigral distribution and sparing of the cortex, hippocampus and motor neurons. The genetic cause of Perry syndrome was recently identified with five mutations in the dynactin gene (DCTN1) segregating with disease in eight families. DCTN1 encodes p150(glued), the major subunit of the dynactin protein complex, which plays a crucial role in retrograde axonal and cytoplasmic transport of various cargoes. Evidence suggests the Perry mutations alter the binding of p150(glued) to microtubules. Further studies will examine reasons for the vulnerability of selected neuronal populations in Perry syndrome, and the link between the genetic defect and TDP-43 pathology.

Association of the MAPT Locus with Parkinson's Disease

European Journal of Neurology : the Official Journal of the European Federation of Neurological Societies. Mar, 2010  |  Pubmed ID: 19912324

Whilst an association between the tau gene (MAPT)-containing H1 haplotype and supranuclear gaze palsy (PSP) has long been recognized, the effect of H1 on risk for Parkinson's disease (PD) has remained more contentious.

Glucocerebrosidase Mutations Are Not a Common Risk Factor for Parkinson Disease in North Africa

Neuroscience Letters. Jun, 2010  |  Pubmed ID: 19945510

Mutations in the glucocerebrosidase gene (GBA) have recently been associated with an increased risk of Parkinson disease (PD). GBA mutations have been observed to be particularly prevalent in the Ashkenazi Jewish population. Interestingly, this population also has a high incidence of the Lrrk2 p.G2019S mutation which is similar in North African Arab-Berber populations. Herein, our sequencing of the GBA gene, in 33 North African Arab-Berber familial parkinsonism probands, identified two novel mutations in three individuals (p.K-26R and p.K186R). Segregation analysis of these two variants did not support a pathogenic role. Genotyping of p.K-26R, p.K186R and the common p.N370S in an ethnically matched series consisting of 395 patients with PD and 372 control subjects did not show a statistically significant association (P>0.05). The p.N370S mutation was only identified in 1 sporadic patient with PD and 3 control subjects indicating that the frequency of this mutation in the North African Arab-Berber population is much lower than that observed in Ashkenazi Jews, and therefore arose in the latter after expansion of the Lrrk2 p.G2019S variant in North Africa.

Depression in Parkinson's Disease

The Canadian Journal of Neurological Sciences. Le Journal Canadien Des Sciences Neurologiques. Jan, 2010  |  Pubmed ID: 20169775

To examine predictive factors associated with onset of depression among individuals diagnosed with Parkinson's disease (PD).

Clinical Implications of Gene Discovery in Parkinson's Disease and Parkinsonism

Movement Disorders : Official Journal of the Movement Disorder Society. 2010  |  Pubmed ID: 20187245

Over the past decade, major progress has been achieved in the identification of genes associated with Parkinson's disease (PD) and parkinsonism. Five genes have now been shown conclusively to play a role in PD susceptibility. Mutations in three of these genes, PRKN, PINK1, and DJ1, are important in early onset, recessively inherited PD, while mutations in LRRK2 and SNCA result in autosomal-dominant PD. LRRK2 has emerged as the most prevalent genetic cause of PD and has been implicated in both familial and sporadic forms of disease. In addition, autosomal-dominant dementia and Parkinsonism has been shown to be caused by mutations in the MAPT and PGRN genes. Molecular tests are now commercially available for several of these genes; however, in some of them, positive results need to be interpreted with caution until penetrance is better understood. In addition, clinical treatment of PD remains largely unaltered by the results of genetic testing.

Leucine-rich Repeat Kinase 2 Gene-associated Disease: Redefining Genotype-phenotype Correlation

Neuro-degenerative Diseases. 2010  |  Pubmed ID: 20197701

Leucine-rich repeat kinase 2 (LRRK2) has emerged as the most prevalent genetic cause of Parkinson's disease (PD) among Caucasians. Patients carrying an LRRK2 mutation display significant variability of clinical and pathologic phenotypes across and within affected families.

LINGO1 and LINGO2 Variants Are Associated with Essential Tremor and Parkinson Disease

Neurogenetics. Oct, 2010  |  Pubmed ID: 20369371

Genetic variation in the leucine-rich repeat and Ig domain containing 1 gene (LINGO1) was recently associated with an increased risk of developing essential tremor (ET) and Parkinson disease (PD). Herein, we performed a comprehensive study of LINGO1 and its paralog LINGO2 in ET and PD by sequencing both genes in patients (ET, n=95; PD, n=96) and by examining haplotype-tagging single-nucleotide polymorphisms (tSNPs) in a multicenter North American series of patients (ET, n=1,247; PD, n= 633) and controls (n=642). The sequencing study identified six novel coding variants in LINGO1 (p.S4C, p.V107M, p.A277T, p.R423R, p.G537A, p.D610D) and three in LINGO2 (p.D135D, p.P217P, p.V565V), however segregation analysis did not support pathogenicity. The association study employed 16 tSNPs at the LINGO1 locus and 21 at the LINGO2 locus. One variant in LINGO1 (rs9652490) displayed evidence of an association with ET (odds ratio (OR) =0.63; P=0.026) and PD (OR=0.54; P=0.016). Additionally, four other tSNPs in LINGO1 and one in LINGO2 were associated with ET and one tSNP in LINGO2 associated with PD (P<0.05). Further analysis identified one tSNP in LINGO1 and two in LINGO2 which influenced age at onset of ET and two tSNPs in LINGO1 which altered age at onset of PD (P<0.05). Our results support a role for LINGO1 and LINGO2 in determining risk for and perhaps age at onset of ET and PD. Further studies are warranted to confirm these findings and to determine the pathogenic mechanisms involved.

Association of Pyridoxal Kinase and Parkinson Disease

Annals of Neurology. Mar, 2010  |  Pubmed ID: 20373354

Cancer Pain: Part 2: Physical, Interventional and Complimentary Therapies; Management in the Community; Acute, Treatment-related and Complex Cancer Pain: a Perspective from the British Pain Society Endorsed by the UK Association of Palliative Medicine and the Royal College of General Practitioners

Pain Medicine (Malden, Mass.). Jun, 2010  |  Pubmed ID: 20456069

This discussion document about the management of cancer pain is written from the pain specialists' perspective in order to provoke thought and interest in a multimodal approach to the management of cancer pain, not just towards the end of life, but pain at diagnosis, as a consequence of cancer therapies, and in cancer survivors. It relates the science of pain to the clinical setting and explains the role of psychological, physical, interventional and complementary therapies in cancer pain.

Genetics of Parkinson Disease and Essential Tremor

Current Opinion in Neurology. Aug, 2010  |  Pubmed ID: 20489616

Elucidating the genetic background of Parkinson disease and essential tremor is crucial to understand the pathogenesis and improve diagnostic and therapeutic strategies.

Establishing Partnerships to Recruit and Retain Critical Care Nurses

Journal for Nurses in Staff Development : JNSD : Official Journal of the National Nursing Staff Development Organization. May-Jun, 2010  |  Pubmed ID: 20508419

The current need to increase numbers of critical care nurses presents an exciting opportunity for nurses in staff development. Partnerships forged between university faculty and nurses have potential to recruit students into critical care settings. This article describes a course taught by faculty and practicing nurses that encourages students to pursue careers in critical care. The success of this initiative provides evidence that academic and clinical partnerships can develop a critical care nurse workforce.

Monitoring Bortezomib Therapy in Multiple Myeloma: Screening of Cyclin D1, D2, and D3 Via Reliable Real-time Polymerase Chain Reaction and Association with Clinico-pathological Features and Outcome

Leukemia & Lymphoma. Sep, 2010  |  Pubmed ID: 20578819

Cyclins D1, D2, and D3 (CCND1, 2, 3) are regulated by proteasomal degradation. Their overexpression in multiple myeloma (MM) has prognostic value. We performed this pilot study to analyze a possible association between CCND1-3 overexpression and response to treatment with the proteasome inhibitor bortezomib, since a specific prognostic marker for bortezomib response has not been reported, but would be ideal to predict who benefits most from bortezomib in times of several potentially efficient therapeutic options. Bone marrow (BM) specimens of 20/47 consecutive patients were available for reliable CCND1-3 analyses by real-time PCR. With CCND1 overexpression in 9/20 patients, the risk for progression after bortezomib treatment was significantly decreased (HR 0.102, 95% CI 0.021-0.498, p = 0.0048) and progression-free survival substantially prolonged (p = 0.0011). Our study is the first to suggest that overexpressed CCND1 in MM is an independent prognostic marker associated with a more durable response to bortezomib. These preliminary results warrant a larger study.

Novel Pathogenic LRRK2 P.Asn1437His Substitution in Familial Parkinson's Disease

Movement Disorders : Official Journal of the Movement Disorder Society. Oct, 2010  |  Pubmed ID: 20669305

Genealogical investigation of a large Norwegian family (F04) with autosomal dominant parkinsonism has identified 18 affected family members over four generations. Genetic studies have revealed a novel pathogenic LRRK2 mutation c.4309 A>C (p.Asn1437His) that co-segregates with disease manifestation (LOD = 3.15, θ = 0). Affected carriers have an early age at onset (48 ± 7.7 SD years) and are clinically asymmetric and levodopa responsive. The variant was absent in 623 Norwegian control subjects. Further screening of patients from the same population identified one additional affected carrier (1 of 692) with familial parkinsonism who shares the same haplotype. The mutation is located within the Roc domain of the protein and enhances GTP-binding and kinase activity, further implicating these activities as the mechanisms that underlie LRRK2-linked parkinsonism.

Association of Alpha-, Beta-, and Gamma-Synuclein with Diffuse Lewy Body Disease

Archives of Neurology. Aug, 2010  |  Pubmed ID: 20697047

To determine the association of the genes that encode alpha-, beta-, and gamma-synuclein (SNCA, SNCB, and SNCG, respectively) with diffuse Lewy body disease (DLBD).

Complementary and Alternative Medicine Use in England: Results from a National Survey

International Journal of Clinical Practice. Oct, 2010  |  Pubmed ID: 20698902

In many countries, recent data on the use of complementary and alternative medicine (CAM) are available. However, in England, there is a paucity of such data. We sought to determine the prevalence and predictors of CAM use in England.

Comprehensive Sequencing of the LRRK2 Gene in Patients with Familial Parkinson's Disease from North Africa

Movement Disorders : Official Journal of the Movement Disorder Society. Oct, 2010  |  Pubmed ID: 20721913

The LRRK2 gene is a key player in Parkinson's disease (PD), however prevalence and pathogenicity of LRRK2 variants remain to be investigated in ethnically diverse populations. Herein, we performed comprehensive sequencing of the LRRK2 gene in 92 Tunisian probands with familial PD. We then performed an association study using all identified variants in a series of 167 Lrrk2 p.G2019S-negative patients with sporadic PD and 365 Lrrk2 p.G2019S-negative healthy control subjects, all from the same Arab-Berber ethnicity. We identified one novel coding substitution (p.M2408I) and 24 known coding changes. Only the Lrrk2 p.G2019S mutation segregated with disease within families and was found in 39% of familial probands. None of the variants displayed significant association with risk for sporadic PD, however a trend was observed for Lrrk2 p.Y2189C. The present study underscores the importance of the LRRK2 gene in the Tunisian PD population.

Profound Cardioprotection with Chloramphenicol Succinate in the Swine Model of Myocardial Ischemia-reperfusion Injury

Circulation. Sep, 2010  |  Pubmed ID: 20837911

Emerging evidence suggests that "adaptive" induction of autophagy (the cellular process responsible for the degradation and recycling of proteins and organelles) may confer a cardioprotective phenotype and represent a novel strategy to limit ischemia-reperfusion injury. Our aim was to test this paradigm in a clinically relevant, large animal model of acute myocardial infarction.

Cerebral and Somatic Venous Oximetry in Adults and Infants

Surgical Neurology International. 2010  |  Pubmed ID: 21170366

The development in the last decade of noninvasive, near infrared spectroscopy (NIRS) analysis of tissue hemoglobin saturation in vivo has provided a new and dramatic tool for the management of hemodynamics, allowing early detection and correction of imbalances in oxygen delivery to the brain and vital organs.

Food Supplements for Body Weight Reduction: a Systematic Review of Systematic Reviews

Obesity (Silver Spring, Md.). Feb, 2011  |  Pubmed ID: 20814412

Structural Analysis of the Conserved Ubiquitin-binding Motifs (UBMs) of the Translesion Polymerase Iota in Complex with Ubiquitin

The Journal of Biological Chemistry. Jan, 2011  |  Pubmed ID: 20929865

Ubiquitin-binding domains (UBDs) provide specificity to the ubiquitin system, which is also involved in translesion synthesis (TLS) in eukaryotic cells. Upon DNA damage, the UBDs (UBM domains) of polymerase iota (Pol ι) interact with ubiquitinated proliferating cell nuclear antigen to regulate the interchange between processive DNA polymerases and TLS. We report a biophysical analysis and solution structures of the two conserved UBM domains located in the C-terminal tail of murine Pol ι in complex with ubiquitin. The 35-amino acid core folds into a helix-turn-helix motif, which belongs to a novel domain fold. Similar to other UBDs, UBMs bind to ubiquitin on the hydrophobic surface delineated by Leu-8, Ile-44, and Val-70, however, slightly shifted toward the C terminus. In addition, UBMs also use electrostatic interactions to stabilize binding. NMR and fluorescence spectroscopy measurements revealed that UBMs bind monoubiquitin, and Lys-63- but not Lys-48-linked chains. Importantly, these biophysical data are supported by functional studies. Indeed, yeast cells expressing ubiquitin mutants specifically defective for UBM binding are viable but sensitive to DNA damaging conditions that require TLS for repair.

SNCA, MAPT, and GSK3B in Parkinson Disease: a Gene-gene Interaction Study

European Journal of Neurology : the Official Journal of the European Federation of Neurological Societies. Jun, 2011  |  Pubmed ID: 21159074

Recent evidence suggests that variation in the SNCA, MAPT, and GSK3B genes interacts in affecting risk for Parkinson disease (PD). In the current study, we attempt to validate previously published findings, evaluating gene-gene interactions between SNCA, MAPT, and GSK3B in association with PD.

Acute Induction of Autophagy As a Novel Strategy for Cardioprotection: Getting to the Heart of the Matter

Autophagy. Apr, 2011  |  Pubmed ID: 21187719

There is no question that necrosis and apoptosis contribute to cardiomyocyte death in the setting of myocardial ischemia-reperfusion. Indeed, considerable effort and resources have been invested in the development of novel therapies aimed at attenuating necrotic and apoptotic cell death, with the ultimate goal of applying these strategies to reduce infarct size and improve outcome in patients suffering acute myocardial infarction (MI) or 'heart attack'. However, an issue that remains controversial is the role of autophagy in determining the fate of ischemic-reperfused cardiomyocytes: i.e., is induction of autophagy detrimental or protective? Recent data from our group obtained in the clinically relevant, in vivo swine model of acute MI provides novel evidence of a positive association between pharmacological upregulation of autophagy (achieved by administration of chloramphenicol succinate (CAPS)) and increased resistance to myocardial ischemia-reperfusion injury.

The Use of Garcinia Extract (Hydroxycitric Acid) As a Weight Loss Supplement: A Systematic Review and Meta-Analysis of Randomised Clinical Trials

Journal of Obesity. 2011  |  Pubmed ID: 21197150

The aim of this systematic review is to examine the efficacy of Garcinia extract, hydroxycitric acid (HCA) as a weight reduction agent, using data from randomised clinical trials (RCTs). Electronic and nonelectronic searches were conducted to identify relevant articles, with no restrictions in language or time. Two independent reviewers extracted the data and assessed the methodological quality of included studies. Twenty-three eligible trials were identified and twelve were included. Nine trials provided data suitable for statistical pooling. The meta-analysis revealed a small, statistically significant difference in weight loss favouring HCA over placebo (MD: -0.88 kg; 95% CI: -1.75, -0.00). Gastrointestinal adverse events were twice as common in the HCA group compared with placebo in one included study. It is concluded that the RCTs suggest that Garcinia extracts/HCA can cause short-term weight loss. The magnitude of the effect is small, and the clinical relevance is uncertain. Future trials should be more rigorous and better reported.

Successful Heart and Liver Transplantation in a Swiss Patient with Glu89Lys Transthyretin Amyloidosis

Transplantation. Mar, 2011  |  Pubmed ID: 21383601

Early and Mature Endothelial Progenitors and VEGFR2+-cells in Multiple Myeloma: Association with Disease Characteristics and Variation in Different Cell Compartments

Leukemia Research. Sep, 2011  |  Pubmed ID: 21684596

We analyzed (1) early endothelial progenitors (EPCs; CD34(+)/AC133(+)/VEGFR2(+)), mature EPCs (CD34(+)/VEGFR2(+)) and VEGFR2(+)-cells in bone marrow (BM)-specimens of multiple myeloma (MM)- vs. monoclonal gammopathy (MGUS)-patients and healthy controls; (2) differences of BM-, peripheral blood (PB)- and leukapheresis (LP)-samples; and (3) the association of EPCs and VEGFR2(+)-cells with MM-parameters. MM patients demonstrated highest early and mature EPCs and VEGFR2(+)-cells in the BM, particularly with advanced and active disease. Endothelial cells differed in BM-, PB- and LP-specimens, albeit seemed less associated with unfavorable prognostic MM-parameters. Our data suggest that especially VEGFR2(+)-cells and mature EPCs in MM are of value to explore further.

Near-infrared Spectroscopy Monitoring of Cerebral Oxygen During Assisted Ventilation

Surgical Neurology International. 2011  |  Pubmed ID: 21697979

Changes in the arterial partial pressure of CO(2) (PaCO(2)) has a direct though transient effect on the cerebral vasculature and cerebral circulation. Decreased PaCO(2) levels lead to vasoconstriction and can result in dangerously low levels of cerebral perfusion that resolve in 4-6 h. It is currently believed that perfusion abnormalities contribute to intraventricular hemorrhage (IVH) and periventricular leukomalacia (PVL) in the neonate. PaCO(2)-induced vasoconstriction may contribute to the pathology of IVH and PVL.

Death-associated Protein Kinase 1 Variation and Parkinson's Disease

European Journal of Neurology : the Official Journal of the European Federation of Neurological Societies. Aug, 2011  |  Pubmed ID: 21749573

  Mutations of the LRRK2 gene are now recognized as major risk factors for Parkinson's disease. The Lrrk2 protein is a member of the ROCO family, which also includes Lrrk1 and Dapk1. Functional genetic variants of the DAPK1 gene (rs4877365 and rs4878104) have been previously associated with Alzheimer's disease.

VPS35 Mutations in Parkinson Disease

American Journal of Human Genetics. Jul, 2011  |  Pubmed ID: 21763482

The identification of genetic causes for Mendelian disorders has been based on the collection of multi-incident families, linkage analysis, and sequencing of genes in candidate intervals. This study describes the application of next-generation sequencing technologies to a Swiss kindred presenting with autosomal-dominant, late-onset Parkinson disease (PD). The family has tremor-predominant dopa-responsive parkinsonism with a mean onset of 50.6 ± 7.3 years. Exome analysis suggests that an aspartic-acid-to-asparagine mutation within vacuolar protein sorting 35 (VPS35 c.1858G>A; p.Asp620Asn) is the genetic determinant of disease. VPS35 is a central component of the retromer cargo-recognition complex, is critical for endosome-trans-golgi trafficking and membrane-protein recycling, and is evolutionarily highly conserved. VPS35 c.1858G>A was found in all affected members of the Swiss kindred and in three more families and one patient with sporadic PD, but it was not observed in 3,309 controls. Further sequencing of familial affected probands revealed only one other missense variant, VPS35 c.946C>T; (p.Pro316Ser), in a pedigree with one unaffected and two affected carriers, and thus the pathogenicity of this mutation remains uncertain. Retromer-mediated sorting and transport is best characterized for acid hydrolase receptors. However, the complex has many types of cargo and is involved in a diverse array of biologic pathways from developmental Wnt signaling to lysosome biogenesis. Our study implicates disruption of VPS35 and retromer-mediated trans-membrane protein sorting, rescue, and recycling in the neurodegenerative process leading to PD.

Dose-dependent Hemodynamic and Metabolic Effects of Vasoactive Medications in Normotensive, Anesthetized Neonatal Piglets

Pediatric Research. Nov, 2011  |  Pubmed ID: 21775923

The developmentally regulated hemodynamic effects of vasoactive medications have not been well characterized. We used traditional and near-infrared spectroscopy monitoring technologies and investigated the changes in heart rate, blood pressure, common carotid artery (CCA) blood flow (BF), cerebral, renal, intestinal, and muscle regional tissue O2 saturation, and acid-base and electrolyte status in response to escalating doses of vasoactive medications in normotensive anesthetized neonatal piglets. We used regional tissue O2 saturation and CCA BF as surrogates of organ and systemic BF, respectively, and controlled minute ventilation and oxygenation. Low to medium doses of dopamine, epinephrine, dobutamine, and norepinephrine increased blood pressure and systemic and regional BF in a drug-specific manner, whereas milrinone exerted minimal effects. At higher doses, dopamine, epinephrine, and norepinephrine but not dobutamine decreased systemic, renal, intestinal, and muscle BF, while cerebral BF remained unchanged. Epinephrine induced significant increases in muscle BF and serum glucose and lactate concentrations. The findings reveal novel drug- and dose-specific differences in the hemodynamic response to escalating doses of vasoactive medications in the neonatal cardiovascular system and provide information for future clinical studies investigating the use of vasoactive medications for the treatment of neonatal cardiovascular compromise.

Structure, Folding and Stability of FimA, the Main Structural Subunit of Type 1 Pili from Uropathogenic Escherichia Coli Strains

Journal of Molecular Biology. Sep, 2011  |  Pubmed ID: 21816158

Filamentous type 1 pili are responsible for attachment of uropathogenic Escherichia coli strains to host cells. They consist of a linear tip fibrillum and a helical rod formed by up to 3000 copies of the main structural pilus subunit FimA. The subunits in the pilus interact via donor strand complementation, where the incomplete, immunoglobulin-like fold of each subunit is complemented by an N-terminal donor strand of the subsequent subunit. Here, we show that folding of FimA occurs at an extremely slow rate (half-life: 1.6 h) and is catalyzed more than 400-fold by the pilus chaperone FimC. Moreover, FimA is capable of intramolecular self-complementation via its own donor strand, as evidenced by the loss of folding competence upon donor strand deletion. Folded FimA is an assembly-incompetent monomer of low thermodynamic stability (-10.1 kJ mol(-1)) that can be rescued for pilus assembly at 37 °C because FimC selectively pulls the fraction of unfolded FimA molecules from the FimA folding equilibrium and allows FimA refolding on its surface. Elongation of FimA at the C-terminus by its own donor strand generated a self-complemented variant (FimAa) with alternative folding possibilities that spontaneously adopts the more stable conformation (-85.0 kJ mol(-1)) in which the C-terminal donor strand is inserted in the opposite orientation relative to that in FimA. The solved NMR structure of FimAa revealed extensive β-sheet hydrogen bonding between the FimA pilin domain and the C-terminal donor strand and provides the basis for reconstruction of an atomic model of the pilus rod.

4D APSY-HBCB(CG)CDHD Experiment for Automated Assignment of Aromatic Amino Acid Side Chains in Proteins

Journal of Biomolecular NMR. Nov, 2011  |  Pubmed ID: 21947871

A four-dimensional (4D) APSY (automated projection spectroscopy)-HBCB(CG)CDHD experiment is presented. This 4D experiment correlates aromatic with aliphatic carbon and proton resonances from the same amino acid side chain of proteins in aqueous solution. It thus allows unambiguous sequence-specific assignment of aromatic amino acid ring signals based on backbone assignments. Compared to conventional 2D approaches, the inclusion of evolution periods on (1)H(β) and (13)C(δ) efficiently removes overlaps, and provides two additional frequencies for consequent automated or manual matching. The experiment was successfully applied to three proteins with molecular weights from 6 to 13 kDa. For the complementation of the assignment of the aromatic resonances, TOCSY- or COSY-based versions of a 4D APSY-HCCH(aro) sequence are proposed.

Automated Projection Spectroscopy and Its Applications

Topics in Current Chemistry. 2012  |  Pubmed ID: 21710379

This chapter presents the NMR technique APSY (automated projection spectroscopy) and its applications for sequence-specific resonance assignments of proteins. The result of an APSY experiment is a list of chemical shift correlations for an N-dimensional NMR spectrum (N≥3). This list is obtained in a fully automated way by the dedicated algorithm GAPRO (geometric analysis of projections) from a geometric analysis of experimentally recorded, low-dimensional projections. Because the positions of corresponding peaks in multiple projections are correlated, thermal noise and other uncorrelated artifacts are efficiently suppressed. We describe the theoretical background of the APSY method and discuss technical aspects that guide its optimal use. Further, applications of APSY-NMR spectroscopy for fully automated sequence-specific backbone and side chain assignments of proteins are described. We discuss the choice of suitable experiments for this purpose and show several examples. APSY is of particular interest for the assignment of soluble unfolded proteins, which is a time-consuming task by conventional means. With this class of proteins, APSY-NMR experiments with up to seven dimensions have been recorded. Sequence-specific assignments of protein side chains in turn are obtained from a 5D TOCSY-APSY-NMR experiment.

Loss of Ability to Work and Ability to Live Independently in Parkinson's Disease

Parkinsonism & Related Disorders. Feb, 2012  |  Pubmed ID: 21975262

Ability to work and live independently is of particular concern for patients with Parkinson's disease (PD). We studied a series of PD patients able to work or live independently at baseline, and evaluated potential risk factors for two separate outcomes: loss of ability to work and loss of ability to live independently.

Sugar-to-base Correlation in Nucleic Acids with a 5D APSY-HCNCH or Two 3D APSY-HCN Experiments

Journal of Biomolecular NMR. Feb, 2012  |  Pubmed ID: 22143941

A five-dimensional (5D) APSY (automated projection spectroscopy) HCNCH experiment is presented, which allows unambiguous correlation of sugar to base nuclei in nucleic acids. The pulse sequence uses multiple quantum (MQ) evolution which enables long constant-time evolution periods in all dimensions, an improvement that can also benefit non-APSY applications. Applied with an RNA with 23 nucleotides the 5D APSY-HCNCH experiment produced a complete and highly precise 5D chemical shift list within 1.5 h. Alternatively, and for molecules where the out-and-stay 5D experiment sensitivity is not sufficient, a set of out-and-back 3D APSY-HCN experiments is proposed: an intra-base (3D APSY-b-HCN) experiment in an MQ or in a TROSY version, and an MQ sugar-to-base (3D APSY-s-HCN) experiment. The two 3D peak lists require subsequent matching via the N1/9 chemical shift values to one 5D peak list. Optimization of the 3D APSY experiments for maximal precision in the N1/9 dimension allowed matching of all (15)N chemical shift values contained in both 3D peak lists. The precise 5D chemical shift correlation lists resulting from the 5D experiment or a pair of 3D experiments also provide a valuable basis for subsequent connection to chemical shifts derived with other experiments.

Genetics of Essential Tremor

Parkinsonism & Related Disorders. Jan, 2012  |  Pubmed ID: 22166413

Essential tremor (ET) is a prevalent condition manifesting with progressive action tremor. Although ET was traditionally viewed as a sporadic disease, a significant proportion of cases report a positive family history of tremor. Autosomal dominant inheritance can be demonstrated in many families. Previously, genome-wide linkage studies in families mapped three loci for ET, hereditary essential tremor-1 (ETM1), ETM2 and ETM3. However, no causal mutation has been replicated in candidate genes within these loci, including dopamine D3 receptor (DRD3) and HS1-binding protein 3 (HS1BP3). Recently, the first genome-wide association study in ET followed by replication studies conducted in diverse populations identified a significant association between the leucine-rich repeat and Ig domain containing 1 gene (LINGO1) SNP rs9652490 and risk for ET Although further novel variants were indentified in LINGO1 and its paralog LINGO2 that may be associated with risk for ET, the pathogenic mechanisms involved remain elusive. Given the possibility that ET as a complex trait may be influenced by the combined effects of rare variants, novel high-throughput technologies sequencing all exons across the genome (exome sequencing) or the whole genome (genome sequencing) may become crucial in understanding/deciphering the genetic background of ET.

Overview of Primary Monogenic Dystonia

Parkinsonism & Related Disorders. Jan, 2012  |  Pubmed ID: 22166420

Primary monogenic forms of dystonia manifest solely or mainly with dystonia; they have been linked to a number of genes and loci and assigned "DYT" numbers. The pure dystonia syndrome early-onset primary dystonia (DYT1) manifests with dominantly-inherited generalized dystonia, often with focal onset in a limb. DYT1 is caused by a GAG deletion in the TOR1A gene. Mutations in the THAP1 gene cause DYT6, a form of pure dystonia that primarily involves cranio-cervical and upper limb muscles. Patients with the dystonia plus syndrome DYT5 display levodopa-responsive dystonia sometimes associated with tremor or parkinsonism (DYT5a, mutations in GCH1); a more severe phenotype with psychomotor involvement can be seen in recessive forms (DYT5b with TH mutations, SPR-deficiency syndrome). Other forms of dystonia plus syndromes include myoclonic dystonia (DYT11) and rapid-onset dystonia-parkinsonism (DYT12). Finally, paroxysmal exertion-induced dystonia (DYT18, GLUT1 deficiency) is caused by mutations in the SLC2A1 gene (DYT9 and DYT18). It is part of the paroxysmal dystonia group and manifests with paroxystic movements sometimes associated with seizures and psychomotor developmental delay.

Mutations in the Colony Stimulating Factor 1 Receptor (CSF1R) Gene Cause Hereditary Diffuse Leukoencephalopathy with Spheroids

Nature Genetics. Feb, 2012  |  Pubmed ID: 22197934

Hereditary diffuse leukoencephalopathy with spheroids (HDLS) is an autosomal-dominant central nervous system white-matter disease with variable clinical presentations, including personality and behavioral changes, dementia, depression, parkinsonism, seizures and other phenotypes. We combined genome-wide linkage analysis with exome sequencing and identified 14 different mutations affecting the tyrosine kinase domain of the colony stimulating factor 1 receptor (encoded by CSF1R) in 14 families with HDLS. In one kindred, we confirmed the de novo occurrence of the mutation. Follow-up sequencing identified an additional CSF1R mutation in an individual diagnosed with corticobasal syndrome. In vitro, CSF-1 stimulation resulted in rapid autophosphorylation of selected tyrosine residues in the kinase domain of wild-type but not mutant CSF1R, suggesting that HDLS may result from partial loss of CSF1R function. As CSF1R is a crucial mediator of microglial proliferation and differentiation in the brain, our findings suggest an important role for microglial dysfunction in HDLS pathogenesis.

When Funds for Professional Development Are Scarce

Journal of Continuing Education in Nursing. Jan, 2012  |  Pubmed ID: 22214413

This column describes an approach to sustaining interprofessional education for perioperative staff when budgetary cuts in professional education significantly limit professional development.

An Evaluation of the Impact of MAPT, SNCA and APOE on the Burden of Alzheimer's and Lewy Body Pathology

Journal of Neurology, Neurosurgery, and Psychiatry. Apr, 2012  |  Pubmed ID: 22291217

The study investigates the effects of genetic factors on the pathology of Alzheimer's disease (AD) and Lewy body (LB) diseases, including Parkinson's disease and dementia with Lewy bodies.

Quality of Herbal Medicines: Challenges and Solutions

Complementary Therapies in Medicine. Feb-Apr, 2012  |  Pubmed ID: 22305255

The popularity of herbal medicines has risen worldwide. This increase in usage renders safety issues important. Many adverse events of herbal medicines can be attributed to the poor quality of the raw materials or the finished products. Different types of herbal medicines are associated with different problems. Quality issues of herbal medicines can be classified into two categories: external and internal. In this review, external issues including contamination (e.g. toxic metals, pesticides residues and microbes), adulteration and misidentification are detailed. Complexity and non-uniformity of the ingredients in herbal medicines are the internal issues affecting the quality of herbal medicines. Solutions to the raised problems are discussed. The rigorous implementation of Good Agricultural and Collection Practices (GACP) and Good Manufacturing Practices (GMP) would undoubtedly reduce the risk of external issues. Through the use of modern analytical methods and pharmaceutical techniques, previously unsolved internal issues have become solvable. Standard herbal products can be manufactured from the standard herbal extracts.

Identifying and Responding to Child Abuse in the Home

Home Healthcare Nurse. Feb, 2012  |  Pubmed ID: 22306752

Given the sheer numbers of abused children, home health clinicians will likely encounter youngsters who are living in volatile and neglectful homes. This article details information that is designed to assist clinicians to identify and respond to child abuse and neglect.

Characterizing the Mechanical Parameters of Forward and Backward Falls As Experienced in Snowboarding

Sports Biomechanics / International Society of Biomechanics in Sports. Mar, 2012  |  Pubmed ID: 22518945

Wrist injuries are frequently observed after falls in snowboarding. In this study, laboratory experiments mimicking forward and backward falls were analysed. In six different falling scenarios, participants self-initiated falls from a static initial position. Eighteen volunteers conducted a total of 741 trials. Measurements were taken for basic parameters describing the kinematics as well as the biomechanical loading during impact, such as impact force, impact acceleration, and velocity. The effective mass affecting the wrist in a fall also was determined. The elbow angle at impact showed a more extended arm in backward falls compared to forward falls, whereas the wrist angle at impact remained similar in forward and backward falls. The study results suggest a new performance standard for wrist guards, indicating the following parameters to characterize an impact: an effective mass acting on one wrist of 3-5 kg, an impact angle of 75 degrees of the forearm relative to the ground, and an impact velocity of 3 m/s.

MRI Characteristics and Scoring in HDLS Due to CSF1R Gene Mutations

Neurology. Aug, 2012  |  Pubmed ID: 22843259

To describe the brain MRI characteristics of hereditary diffuse leukoencephalopathy with spheroids (HDLS) with known mutations in the colony-stimulating factor 1 receptor gene (CSF1R) on chromosome 5.

Automated Projection Spectroscopy (APSY) for the Assignment of NMR Resonances of Biological Macromolecules

Chimia. 2012  |  Pubmed ID: 23146263

High resolution nuclear magnetic resonance (NMR) spectroscopy in solution is an established technique in structural biology. Detailed functional and structural studies of biological macromolecules by NMR require the assignment of the chemical shifts to specific nuclei. In biological applications, the necessary data is usually obtained from a number of two- and three-dimensional (2D and 3D) NMR experiments. Often, these data cannot be fully analyzed by automated computer programs due to insufficient separation and resolution of the signals in the available spectra. Then, complete resonance assignment requires manual interaction and can become a long and labor-intensive task. Automated projection spectroscopy (APSY) allows the substantial improvement of the resolution by providing spectral information from four and higher dimensional experiments without measuring the full spectrum, which would by far exceed any acceptable measuring time. APSY only measures a series of projections of the high-dimensional spectrum which can be obtained in a much shorter time. Peak picking of the projection spectra provides the basis for the calculation of the high-dimensional chemical shift correlation space by the algorithm GAPRO. The resulting high-dimensional peak lists are commonly artifact-free and of exceptional precision. Along with their high number of correlated nuclei they provide an ideal basis for reliable automated assignment. We will introduce the basic concepts of APSY, illustrate them with an application of a 6D APSY-seq-HNCOCANH experiment, and discuss some practical aspects.

Effect of Vagus Nerve Stimulation in an Adult Patient with Dravet Syndrome: Contribution to Sudden Unexpected Death in Epilepsy Risk Reduction?

European Neurology. 2013  |  Pubmed ID: 23207687

We report on a patient who developed, from 5 months of age, multiple seizure types, including myoclonic, associated with severe psychomotor delay, leading to the diagnosis of Dravet syndrome. Over the years, he developed refractory epilepsy and was implanted with a vagus nerve stimulator at the age of 19. After 3 months, he experienced a progressive improvement of partial and generalized seizures, with a >90% reduction, and better alertness. This meaningful clinical improvement is discussed in the light of the sudden unexpected death in epilepsy risk, which is high in this setting, and seems remarkably diminished in our patient in view of the reduction of generalized convulsions.

Potent in Vitro and in Vivo Activity of Sorafenib in Multiple Myeloma: Induction of Cell Death, CD138-downregulation and Inhibition of Migration Through Actin Depolymerization

British Journal of Haematology. Apr, 2013  |  Pubmed ID: 23384035

Despite considerable advances, multiple myeloma (MM) remains incurable and the development of novel therapies targeting the interplay between plasma cells (PCs) and their bone marrow (BM) microenvironment remains essential. We investigated the effect of various agents in vitro on the proliferation, phenotype, morphology, actin polymerization and migration of MM cells and, in vivo, the tumour growth of L363-bearing non-obese diabetic severe combined immunodeficient mice with a deficient interleukin-2 receptor gamma chain (NSG). In vitro, we observed a dose-dependent cytotoxicity with bortezomib and sorafenib. Using RPMI8226 cells co-expressing histone 2B-mCherry and cytochrome c-GFP, bortezomib- and sorafenib-induced apoptosis was confirmed, and both agents combined showed synergism. Sorafenib induced CD138-downregulation and abolished CXCL12-induced actin polymerization. L363 cells expressed CCR4 and CCR5 and migrated to their common ligand CCL5. Chemotaxis to BM stroma cells was notable and significantly reduced by sorafenib. Downregulation of phospho-ERK appeared relevant for the inhibition of actin polymerization and chemotaxis. Sorafenib alone, and combined with bortezomib, showed substantial antitumour activity in L363-bearing NSG. Correspondingly, sorafenib induced clinical responses in MM-/AL-amyloidosis patients. We conclude that, in addition to the cytotoxic and anti-angiogenic effects of sorafenib, blocking of MM cell migration and homing represent promising mechanisms to interrupt the interplay between PCs and their supportive microenvironment.

CSF1R Mutations Link POLD and HDLS As a Single Disease Entity

Neurology. Mar, 2013  |  Pubmed ID: 23408870

Pigmented orthochromatic leukodystrophy (POLD) and hereditary diffuse leukoencephalopathy with axonal spheroids (HDLS) are rare neurodegenerative disorders characterized by cerebral white matter abnormalities, myelin loss, and axonal swellings. The striking overlap of clinical and pathologic features of these disorders suggested a common pathogenesis; however, no genetic or mechanistic link between POLD and HDLS has been established. Recently, we reported that mutations in the colony-stimulating factor 1 receptor (CSF1R) gene cause HDLS. In this study, we determined whether CSF1R mutations are also a cause of POLD.

Artichoke Leaf Extract for Treating Hypercholesterolaemia

Cochrane Database of Systematic Reviews (Online). 2013  |  Pubmed ID: 23543518

Hypercholesterolaemia is directly associated with an increased risk for coronary heart disease and other sequelae of atherosclerosis. Artichoke leaf extract (ALE) has been implicated in lowering cholesterol levels. Whether ALE is truly effective for this indication is still a matter of debate. This is an update of a review first published in 2002 and last updated in 2009.

Successful Long-term Bilateral Subthalamic Nucleus Deep Brain Stimulation in VPS35 Parkinson's Disease

Parkinsonism & Related Disorders. Jul, 2013  |  Pubmed ID: 23623008

4D Experiments Measured with APSY for Automated Backbone Resonance Assignments of Large Proteins

Journal of Biomolecular NMR. Apr, 2013  |  Pubmed ID: 23625454

Detailed structural and functional characterization of proteins by solution NMR requires sequence-specific resonance assignment. We present a set of transverse relaxation optimization (TROSY) based four-dimensional automated projection spectroscopy (APSY) experiments which are designed for resonance assignments of proteins with a size up to 40 kDa, namely HNCACO, HNCOCA, HNCACB and HN(CO)CACB. These higher-dimensional experiments include several sensitivity-optimizing features such as multiple quantum parallel evolution in a 'just-in-time' manner, aliased off-resonance evolution, evolution-time optimized APSY acquisition, selective water-handling and TROSY. The experiments were acquired within the concept of APSY, but they can also be used within the framework of sparsely sampled experiments. The multidimensional peak lists derived with APSY provided chemical shifts with an approximately 20 times higher precision than conventional methods usually do, and allowed the assignment of 90 % of the backbone resonances of the perdeuterated primase-polymerase ORF904, which contains 331 amino acid residues and has a molecular weight of 38.4 kDa.

Combination Therapy With Insulin-like Growth Factor-1 and Hypothermia Synergistically Improves Outcome After Transient Global Brain Ischemia in the Rat

Academic Emergency Medicine : Official Journal of the Society for Academic Emergency Medicine. Apr, 2013  |  Pubmed ID: 23701341

Hypothermia has a well-established neuroprotective effect and offers a foundation for combination therapy for brain ischemia. The authors evaluated the effect of combination therapy with insulin-like growth factor-1 (IGF-1) and hypothermia on brain structure and function in the setting of global brain ischemia and reperfusion in rats.

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