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Find video protocols related to scientific articles indexed in Pubmed.
Identification of human TERT elements necessary for telomerase recruitment to telomeres.
Elife
PUBLISHED: 06-03-2014
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Human chromosomes terminate in telomeres, repetitive DNA sequences bound by the shelterin complex. Shelterin protects chromosome ends, prevents recognition by the DNA damage machinery, and recruits telomerase. A patch of amino acids, termed the TEL-patch, on the OB-fold domain of the shelterin component TPP1 is essential to recruit telomerase to telomeres. In contrast, the site on telomerase that interacts with the TPP1 OB-fold is not well defined. In this study, we identify separation-of-function mutations in the TEN-domain of human telomerase reverse transcriptase (hTERT) that disrupt the interaction of telomerase with TPP1 in vivo and in vitro but have very little effect on the catalytic activity of telomerase. Suppression of a TEN-domain mutation with a compensatory charge-swap mutation in the TEL-patch indicates that their association is direct. Our findings define the interaction interface required for telomerase recruitment to telomeres, an important step towards developing modulators of this interaction as therapeutics for human disease.
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Effect of anaerobiosis on indigenous microorganisms in blackwater with fish offal as co-substrate.
Water Res.
PUBLISHED: 05-20-2014
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The aim of this study was to compare the effect of mesophilic anaerobic digestion with aerobic storage on the survival of selected indigenous microorganisms and microbial groups in blackwater, including the effect of addition of Greenlandic Halibut and shrimp offal. The methane yield of the different substrate mixtures was determined in batch experiments to study possible correlation between methanogenic activity in the anaerobic digesters and reduction of indigenous microorganisms in the blackwater. By the end of the experiments a recovery study was conducted to determine possible injury of the microorganisms. In both anaerobic and aerobic samples, survival of Escherichia coli was better in the presence of Greenlandic Halibut offal when compared to samples containing blackwater only and blackwater and shrimp offal, possibly due to more available carbon in the samples containing Greenlandic Halibut offal. Reduction of faecal streptococci was large under both anaerobic and aerobic conditions, and the results indicated a complete removal of faecal streptococci in the anaerobic samples containing blackwater and a mixture of blackwater and shrimp offal after 17 and 31 days, respectively. Amoxicillin resistant bacteria were reduced in the anaerobic samples in the beginning of the study but increased towards the end of it. The opposite pattern was observed in the aerobic samples, with a growth in the beginning followed by a reduction. During the anaerobic digestion tetracycline resistant bacteria showed the least reduction in the mixture of blackwater and shrimp offal, which had the lowest methane yield while the highest reduction was observed in the mixture of blackwater and Greenlandic Halibut, where the highest methane yield was measured Reduction of coliphages was larger under anaerobic conditions. Addition of fish offal had no effect on survival of coliphages. The results of the recovery study indicated that a fraction of the E. coli in the aerobic blackwater sample and of the faecal streptococci in both the anaerobic and aerobic samples containing blackwater and Greenlandic Halibut were injured only, and thus able to resuscitate during recovery. The use of anaerobic digestion in the Arctic is limited to substrate types like those tested in this study because of absence of agriculture. The results indicate that anaerobic digestion of wastewater could benefit from the addition of fish offal, with respect to both microbial reduction and energy production.
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Collagenase followed by compression for the treatment of earlobe keloids.
Dermatol Surg
PUBLISHED: 03-07-2014
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Many therapeutic options are available for treating keloids, but success rates vary widely, and the keloids often recur. The Food and Drug Administration has recently approved intralesional collagenase for the treatment of Dupuytren's contracture. This medication has not been explored for the treatment of earlobe keloids, a common problem.
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Heronapyrrole D: A case of co-inspiration of natural product biosynthesis, total synthesis and biodiscovery.
Beilstein J Org Chem
PUBLISHED: 01-01-2014
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The heronapyrroles A-C have first been isolated from a marine-derived Streptomyces sp. (CMB-0423) in 2010. Structurally, these natural products feature an unusual nitropyrrole system to which a partially oxidized farnesyl chain is attached. The varying degree of oxidation of the sesquiterpenyl subunit in heronapyrroles A-C provoked the hypothesis that there might exist other hitherto unidentified metabolites. On biosynthetic grounds a mono-tetrahydrofuran-diol named heronapyrrole D appeared a possible candidate. We here describe a short asymmetric synthesis of heronapyrrole D, its detection in cultivations of CMB-0423 and finally the evaluation of its antibacterial activity. We thus demonstrate that biosynthetic considerations and the joint effort of synthetic and natural product chemists can result in the identification of new members of a rare class of natural products.
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Inclusion body myositis: from immunopathology and degenerative mechanisms to treatment perspectives.
Expert Rev Clin Immunol
PUBLISHED: 10-21-2013
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Inclusion body myositis is the most common inflammatory myopathy above the age of 50. It becomes clinically apparent around the fourth decade and leads to a slowly, but relentlessly progressive decline in muscular wasting and weakness. The pathology consists of a complex network of inflammatory and degenerative mechanisms, which lead to an attack of muscle fibers by auto-reactive T cells and possibly antibodies. At the same time, various aberrant proteins accumulate within the muscle fibers, including ?-amyloid, tau and ?-synuclein. Several key components of proinflammatory cell stress mechanisms such as nitric oxide production and macroautophagic processing contribute to the muscle fiber damage. So far, none of the anti-inflammatory or immunomodulatory treatment efforts have been able to halt the disease progression and help the patients. In this summary, the current concept of the complex disease pathology of IBM is reviewed with a focus on recent findings as well as future treatment perspectives.
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The Role of FOXP3 in Regulating Immune Responses.
Int. Rev. Immunol.
PUBLISHED: 08-15-2013
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Regulatory T cells (Tregs) act in trans to control immune responses. The suppressive function of Tregs relies heavily on high and stable expression of the transcription factor FOXP3, which, together with other transcription factors, activates anti-inflammatory genes and represses proinflammatory genes. FOXP3 is required to shape the unique signaling mechanisms in Tregs, creating a positive-feedback pathway to further enhance its own expression. In addition, FOXP3 is thought to switch on a complex transcriptional network that leads to the stabilization of the Treg phenotype. Emerging data reveal that FOXP3 achieves this function in concert with several other transcription factors, many of which are associated with lineages of conventional T cells. In this review, we will discuss the structural features of FOXP3 and how it functions by interacting with other transcription factors. We will also summarize the role of FOXP3 in establishing the unique signaling cascades in Tregs. Finally, we will dissect the cooperative roles of FOXP3 and other T-cell lineage-defining transcription factors and discuss how these networks not only control the ability to Tregs to suppress different types of immune responses, but also enable Treg plasticity.
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Indirect viscosimetric method is less accurate than ektacytometry for the measurement of red blood cell deformability.
Clin. Hemorheol. Microcirc.
PUBLISHED: 04-19-2013
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The aim of this study was to test the accuracy of viscosimetric method to estimate the red blood cell (RBC) deformability properties. Thirty-three subjects were enrolled in this study: 6 healthy subjects (AA), 11 patients with sickle cell-hemoglobin C disease (SC) and 16 patients with sickle cell anemia (SS). Two methods were used to assess RBC deformability: 1) indirect viscosimetric method and 2) ektacytometry. The indirect viscosimetric method was based on the Dintenfass equation where blood viscosity, plasma viscosity and hematocrit are measured and used to calculate an index of RBC rigidity (Tk index). The RBC deformability/rigidity of the three groups was compared using the two methods. Tk index was not different between SS and SC patients and the two groups had higher values than AA group. When ektacytometry was used, RBC deformability was lower in SS and SC groups compared to the AA group and SS and SC patients were different. Although the two measures of RBC deformability were correlated, the association was not very high. Bland and Altman analysis demonstrated a 3.25 bias suggesting a slight difference between the two methods. In addition, the limit of agreement represented 28% (>15%) of the mean values of RBC deformability, showing no interchangeability between the two methods. In conclusion, measuring RBC deformability by indirect viscosimetry is less accurate than by ektacytometry, which is considered the gold standard.
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Resonance assignments of the microtubule-binding domain of the C. elegans spindle and kinetochore-associated protein 1.
Biomol NMR Assign
PUBLISHED: 04-10-2013
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During mitosis, kinetochores coordinate the attachment of centromeric DNA to the dynamic plus ends of microtubules, which is hypothesized to pull sister chromatids toward opposing poles of the mitotic spindle. The outer kinetochore Ndc80 complex acts synergistically with the Ska (spindle and kinetochore-associated) complex to harness the energy of depolymerizing microtubules and power chromosome movement. The Ska complex is a hexamer consisting of two copies of the proteins Ska1, Ska2 and Ska3, respectively. The C-terminal domain of the spindle and kinetochore-associated protein 1 (Ska1) is the microtubule-binding domain of the Ska complex. We solved the solution structure of the C. elegans microtubule-binding domain (MTBD) of the protein Ska1 using NMR spectroscopy. Here, we report the resonance assignments of the MTBD of C. elegans Ska1.
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Update on treatment of inclusion body myositis.
Curr Rheumatol Rep
PUBLISHED: 03-27-2013
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Degenerative mechanisms such as protein accumulation and vacuolar transformation in the skeletal muscle distinguish inclusion body myositis (IBM) from other inflammatory myopathies. IBM is particularly common in patients over the age of 50 years and inevitably leads to progressive muscle weakness and atrophy. Conventional immunotherapies, albeit effective in other forms of myositis, seem to have only a transient or no beneficial effect on disease progression of IBM. So far, no established evidence-based treatment exists and therapy recommendations are based on expert opinion. Recent clinical trials using monoclonal antibodies such as alemtuzumab or etanercept have failed to demonstrate efficacy. Different treatment studies with drugs that aim at degenerative disease mechanisms are planned or ongoing. This review aims to provide an overview of the current treatment options for IBM.
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Cell stress molecules in the skeletal muscle of GNE myopathy.
BMC Neurol
PUBLISHED: 03-04-2013
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Mutations of the UDP-N-acetylglucosamine-2-epimerase/N-acetylmannosamine-kinase (GNE)-gene are causally related to GNE myopathy. Yet, underlying pathomechanisms of muscle fibre damage have remained elusive. In sporadic inclusion body myositis (sIBM), the pro-inflammatory cell-stress mediators ?B-crystallin and inducible nitric oxide synthase (iNOS) are crucial markers of the disease pathology.
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Specific humoral immune response to the Thomsen-Friedenreich tumor antigen (CD176) in mice after vaccination with the commensal bacterium Bacteroides ovatus D-6.
Cancer Immunol. Immunother.
PUBLISHED: 01-12-2013
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The tumor-specific Thomsen-Friedenreich antigen (TF?, CD176) is an attractive target for a cancer vaccine, especially as TF-directed antibodies play an important role in cancer immunosurveillance. However, synthetic TF vaccines have not overcome the low intrinsic immunogenicity of TF. Since natural TF-directed antibodies present in human sera are generated in response to microbes found in the gastrointestinal tract, microbial TF structures are obviously more immunogenic than synthetic TF. We recently isolated a new strain (D-6) of the human gut bacterium Bacteroides ovatus, which carries the true TF? antigen. Here, we present experimental data on the immunogenicity of this strain. Mice immunized with B. ovatus D-6 in the absence of adjuvants developed specific anti-TF? IgM and IgG antibodies which also bound to human cancer cells carrying TF?. Our data suggest that B. ovatus D-6 presents a unique TF?-specific immunogenicity based on a combination of several inherent properties including: expression of the true TF? antigen, clustering and accessible presentation of TF? as repetitive side chains on a capsular polysaccharide, and intrinsic adjuvant properties. Therefore, B. ovatus strain D-6 is an almost perfect candidate for the development of the first adjuvant-free TF?-specific anti-tumor vaccine.
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TNF-? upregulates macroautophagic processing of APP/?-amyloid in a human rhabdomyosarcoma cell line.
J. Neurol. Sci.
PUBLISHED: 01-05-2013
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Sporadic inclusion body myositis is a chronic progressive, inflammatory disorder of the skeletal muscle. No effective treatment is available for this debilitating condition and the complex disease pathology is far from being understood. The major hallmark of the pathomechanisms is the co-occurrence of inflammatory as well as degenerative cascades including aggregates consisting of ?-amyloid within skeletal muscle fibers. Macroautophagy, a homeostatic process that shuttles cytoplasmic constituents into endosomal and lysosomal compartments, has recently been shown to be upregulated via the proinflammatory cytokine TNF-? in human skeletal muscle cells. In a human cell line from rhabdomyosarcoma as a model to study muscle cells, we here show that TNF-?-mediated upregulation of macroautophagy modulates APP and ?-amyloid load and can be blocked by inhibition of macroautophagy. Thus, macroautophagy may be a crucial mediator between inflammation and ?-amyloid-associated degeneration in skeletal muscle.
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Preliminary safety evaluation of a new Bacteroides xylanisolvens isolate.
Appl. Environ. Microbiol.
PUBLISHED: 11-18-2011
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Besides conferring some health benefit to the host, a bacterial strain must present an unambiguous safety status to be considered a probiotic. We here present the preliminary safety evaluation of a new Bacteroides xylanisolvens strain (DSM 23964) isolated from human feces. First results suggest that it may be able to provide probiotic health benefits. Its identity was confirmed by biochemical analysis, by sequencing of its 16S rRNA genes, and by DNA-DNA hybridization. Virulence determinants known to occur in the genus Bacteroides, such the bft enterotoxin and other enzymatic activities involved in the degradation of the extracellular matrix and the capsular polysaccharide PS A, were absent in this strain. The investigation of the antibiotic susceptibility indicated that strain DSM 23964 was sensitive to metronidazole, meropenem agents, and clindamycin. Resistance to penicillin and ampicillin was identified to be conferred by the ?-lactamase cepA gene and could therefore be restored by adding ?-lactamase inhibitors. The localization of the cepA gene in the genome of strain DSM 23964 and the absence of detectable plasmids further suggest that a transfer of ?-lactamase activity or the acquisition of other antibiotic resistances are highly improbable. Taken together, the presented data indicate that the strain B. xylanisolvens DSM 23964 has no virulence potential. Since it also resists the action of gastric enzymes and low-pH conditions, this strain is an interesting candidate for further investigation of its safety and potential health-promoting properties.
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E. coli chaperones DnaK, Hsp33 and Spy inhibit bacterial functional amyloid assembly.
Prion
PUBLISHED: 10-01-2011
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Amyloid formation is an ordered aggregation process, where ?-sheet rich polymers are assembled from unstructured or partially folded monomers. We examined how two Escherichia coli cytosolic chaperones, DnaK and Hsp33, and a more recently characterized periplasmic chaperone, Spy, modulate the aggregation of a functional amyloid protein, CsgA. We found that DnaK, the Hsp70 homologue in E. coli, and Hsp33, a redox-regulated holdase, potently inhibited CsgA amyloidogenesis. The Hsp33 anti-amyloidogenesis activity was oxidation dependent, as oxidized Hsp33 was significantly more efficient than reduced Hsp33 at preventing CsgA aggregation. When soluble CsgA was seeded with preformed amyloid fibers, neither Hsp33 nor DnaK were able to efficiently prevent soluble CsgA from adopting the amyloid conformation. Moreover, both DnaK and Hsp33 increased the time that CsgA was reactive with the amyloid oligomer conformation-specific A11 antibody. Since CsgA must also pass through the periplasm during secretion, we assessed the ability of the periplasmic chaperone Spy to inhibit CsgA polymerization. Like DnaK and Hsp33, Spy also inhibited CsgA polymerization in vitro. Overexpression of Spy resulted in increased chaperone activity in periplasmic extracts and in reduced curli biogenesis in vivo. We propose that DnaK, Hsp33 and Spy exert their effects during the nucleation stages of CsgA fibrillation. Thus, both housekeeping and stress induced cytosolic and periplasmic chaperones may be involved in discouraging premature CsgA interactions during curli biogenesis.
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Co-production of ethanol, biogas, protein fodder and natural fertilizer in organic farming--evaluation of a concept for a farm-scale biorefinery.
Bioresour. Technol.
PUBLISHED: 09-24-2011
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The addition of a biorefinery to an organic farm was investigated, where ethanol was produced from germinated rye grains and whey, and the effluent was separated into two streams: the protein-rich solid fraction, to be used as animal feed, and the liquid fraction, which can be co-digested with clover grass silage to produce biogas. A method for ethanol production from rye was applied by utilizing inherent amylase activity from germination of the seed. Biogas potential of ethanol fermentation effluent was measured through anaerobic digestion trials. The effluent from the trials was assumed to serve as natural fertilizer. A technoeconomic analysis was also performed; total capital investment was estimated to be approximately 4 M USD. Setting a methane selling price according to available incentives for "green electricity" (0.72 USD/m(3)) led to a minimum ethanol selling price of 1.89 USD/L (project lifetime 25 yr, at a discount rate 10%).
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Safety assessment of the commensal strain Bacteroides xylanisolvens DSM 23964.
Regul. Toxicol. Pharmacol.
PUBLISHED: 08-31-2011
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We recently isolated and characterized the new strain Bacteroides xylanisolvens DSM 23964 and presented it as potential candidate for the first natural probiotic strain of the genus Bacteroides. In order to evaluate the safety of this strain for use in food, the following standard toxicity assays were conducted with this strain in both viable and pasteurized form: in vitro bacterial reverse mutation assay, in vitro chromosomal aberration assay, and 90day subchronic repeated oral toxicity studies in mice. No mutagenic, clastogenic, or toxic effects were detected even at extremely high doses. In addition, no clinical, hematological, ophthalmological, or histopathological abnormality could be observed after necropsy at any of the doses tested. Hence, the NOAEL could be estimated to be greater than 2.3×10(11) CFUs, and 2.3×10(14) for pasteurized bacteria calculated as equivalent for an average 70kg human being. In addition, the absence of any in vivo pathogenic properties of viable B. xylanisolvens DSM 23964 cells was confirmed by means of an intraperitoneal abscess formation model in mice which also demonstrated that the bacteria are easily eradicated by the hosts immune system. The obtained results support the assumed safety of B. xylanisolvens DSM 23964 for use in food.
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Chromosome segregation: keeping kinetochores in the loop.
Curr. Biol.
PUBLISHED: 02-09-2011
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The Ndc80 complex is a key component of the kinetochore-microtubule interface. Two studies now demonstrate that a conserved loop region within the extended coiled-coil of Ndc80 plays an unexpected role in recruiting proteins to the kinetochore.
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Slip resistance of non-slip socks--an accelerometer-based approach.
Gait Posture
PUBLISHED: 01-10-2011
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The present study investigated the relative slip resistance of commercially available non-slip socks during gait. Twenty-four healthy subjects (29.3±10.4 years) participated in the study. Each subject completed 4 different test conditions (barefoot, non-slip socks, conventional socks, backless slippers) in a randomized, balanced order. The slip resistance was estimated by measuring the heel deceleration time using a heel-mounted accelerometer. Repeated measures ANOVA and post hoc paired-sample t-test with Bonferroni correction were used for statistical analysis. Compared to barefoot walking absolute deceleration times [ms] were significantly increased when wearing conventional socks or slippers. No significant differences were observed between the barefoot and non-slip socks conditions. The present study shows that non-slip socks improved slip-resistance during gait when compared to conventional socks and slippers. Future investigations should verify the present findings in hospital populations prone to slip-related falls.
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TNF-alpha induces macroautophagy and regulates MHC class II expression in human skeletal muscle cells.
J. Biol. Chem.
PUBLISHED: 10-27-2010
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Macroautophagy, a homeostatic process that shuttles cytoplasmic constituents into endosomal and lysosomal compartments, has recently been shown to deliver antigens for presentation on major histocompatibility complex (MHC) class II molecules. Skeletal muscle fibers show a high level of constitutive macroautophagy and express MHC class II molecules upon immune activation. We found that tumor necrosis factor-? (TNF-?), a monokine overexpressed in inflammatory myopathies, led to a marked up-regulation of macroautophagy in skeletal myocytes. Furthermore, TNF-? augmented surface expression of MHC class II molecules in interferon-? (IFN-?)-treated myoblasts. The synergistic effect of TNF-? and IFN-? on the induction of MHC class II surface expression was not reflected by higher intracellular human leukocyte antigen (HLA)-DR levels and was reversed by macroautophagy inhibition, suggesting that TNF-? facilitates antigen processing via macroautophagy for more efficient MHC class II loading. Muscle biopsies from patients with sporadic inclusion body myositis, a well defined myopathy with chronic inflammation, showed that over 20% of fibers that contained autophagosomes costained for MHC class II molecules and that more than 40% of double-positive muscle fibers had contact with CD4(+) and CD8(+) immune cells. These findings establish a mechanism through which TNF-? regulates both macroautophagy and MHC class II expression and suggest that macroautophagy-mediated antigen presentation contributes to the immunological environment of the inflamed human skeletal muscle.
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Aurora B kinase controls the targeting of the Astrin-SKAP complex to bioriented kinetochores.
J. Cell Biol.
PUBLISHED: 10-11-2010
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During mitosis, kinetochores play multiple roles to generate interactions with microtubules, and direct chromosome congression, biorientation, error correction, and anaphase segregation. However, it is unclear what changes at the kinetochore facilitate these distinct activities. Here, we describe a complex of the spindle- and kinetochore-associated protein Astrin, the small kinetochore-associated protein (SKAP), and the dynein light chain LC8. Although most dynein-associated proteins localize to unaligned kinetochores in an Aurora B-dependent manner, Astrin, SKAP, and LC8 localization is antagonized by Aurora B such that they target exclusively to bioriented kinetochores. Astrin-SKAP-depleted cells fail to maintain proper chromosome alignment, resulting in a spindle assembly checkpoint-dependent mitotic delay. Consistent with a role in stabilizing bioriented attachments, Astrin and SKAP bind directly to microtubules and are required for CLASP localization to kinetochores. In total, our results suggest that tension-dependent Aurora B phosphorylation can act to control outer kinetochore composition to provide distinct activities to prometaphase and metaphase kinetochores.
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Pathomechanisms of inflammatory myopathies: recent advances and implications for diagnosis and therapies.
Expert Opin Med Diagn
PUBLISHED: 03-29-2010
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Importance of the field: The main subtypes of inflammatory myopathies include dermatomyositis (DM), polymyositis (PM), necrotising myopathy (NM) and sporadic inclusion body myositis (sIBM). Recent observations have helped us to understand better the unique pathomechanisms of each subset. Advances in the pathogenesis of these disorders have led to a more precise diagnosis and specific therapeutic strategies. Areas covered in this review: A critical review regarding tissue biomarkers for the diagnosis of DM, PM, NM and sIBM is provided and an outline for more effective treatment strategies is discussed, particularly in sIBM, for which there is no effective therapy. What the reader will gain: The reader will gain an objective overview of the different pathomechanisms of the major forms of myositis, the best means of arriving at the correct diagnosis, and a critical outline of the present and future therapeutic strategies. Take home message: Whereas DM is mainly mediated by humoral mechanisms, a T-cell-mediated cytotoxicity is operational in PM and sIBM. NM is multifactorial, but a subset is autoimmune, mediated by macrophages and possibly antibodies. Accumulation of aberrant molecules contributes to the pathology of sIBM. Muscle biopsy is required for the correct diagnosis of each entity. Standard immunotherapy is effective in DM and PM, but not usually in sIBM, for which new treatment strategies are discussed.
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Effect of Alemtuzumab (CAMPATH 1-H) in patients with inclusion-body myositis.
Brain
PUBLISHED: 05-19-2009
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Sporadic inclusion-body myositis (sIBM) is the most common disabling, adult-onset, inflammatory myopathy histologically characterized by intense inflammation and vacuolar degeneration. In spite of T cell-mediated cytotoxicity and persistent, clonally expanded and antigen-driven endomysial T cells, the disease is resistant to immunotherapies. Alemtuzumab is a humanized monoclonal antibody that causes an immediate depletion or severe reduction of peripheral blood lymphocytes, lasting at least 6 months. We designed a proof-of-principle study to examine if one series of Alemtuzumab infusions in sIBM patients depletes not only peripheral blood lymphocytes but also endomysial T cells and alters the natural course of the disease. Thirteen sIBM patients with established 12-month natural history data received 0.3 mg/kg/day Alemtuzumab for 4 days. The study was powered to capture > or =10% increase strength 6 months after treatment. The primary end-point was disease stabilization compared to natural history, assessed by bi-monthly Quantitative Muscle Strength Testing and Medical Research Council strength measurements. Lymphocytes and T cell subsets were monitored concurrently in the blood and the repeated muscle biopsies. Alterations in the mRNA expression of inflammatory, stressor and degeneration-associated molecules were examined in the repeated biopsies. During a 12-month observation period, the patients total strength had declined by a mean of 14.9% based on Quantitative Muscle Strength Testing. Six months after therapy, the overall decline was only 1.9% (P < 0.002), corresponding to a 13% differential gain. Among those patients, four improved by a mean of 10% and six reported improved performance of daily activities. The benefit was more evident by the Medical Research Council scales, which demonstrated a decline in the total scores by 13.8% during the observation period but an improvement by 11.4% (P < 0.001) after 6 months, reaching the level of strength recorded 12 months earlier. Depletion of peripheral blood lymphocytes, including the naive and memory CD8+ cells, was noted 2 weeks after treatment and persisted up to 6 months. The effector CD45RA(+)CD62L(-) cells, however, started to increase 2 months after therapy and peaked by the 4th month. Repeated muscle biopsies showed reduction of CD3 lymphocytes by a mean of 50% (P < 0.008), most prominent in the improved patients, and reduced mRNA expression of stressor molecules Fas, Mip-1a and alphaB-crystallin; the mRNA of desmin, a regeneration-associated molecule, increased. This proof-of-principle study provides insights into the pathogenesis of inclusion-body myositis and concludes that in sIBM one series of Alemtuzumab infusions can slow down disease progression up to 6 months, improve the strength of some patients, and reduce endomysial inflammation and stressor molecules. These encouraging results, the first in sIBM, warrant a future study with repeated infusions
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Ex-situ bioremediation of polycyclic aromatic hydrocarbons in sewage sludge.
J. Hazard. Mater.
PUBLISHED: 05-19-2009
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Polycyclic aromatic hydrocarbons (PAH) are regarded as environmental pollutants. A promising approach to reduce PAH pollution is based on the implementation of the natural potential of some microorganisms to utilize hydrocarbons. In this study Proteiniphilum acetatigenes was used for bioaugmentation of sewage sludge to improve the PAH removal. Bioaugmentation experiments were performed in parallel semi-continuously fed reactors started up with digested primary and secondary sludge. Three bioaugmentation approaches were investigated: A1, addition of bacteria once during starting up; A2, addition of bacteria at the beginning and then every 2nd day and A3, addition of encapsulated bacteria once during starting up. Removal of PAH was found to be both biotic and abiotic. All three approaches had a positive effect of the biological removal of PAH. Highest biological removal of individual PAH (up to 80%) was observed using continuous addition (approach A2) of the bacteria to the reactors. In general, the effect of bioaugmentation was higher in the reactors fed with primary sludge compared to the reactors fed with mixed sludge. Bioaugmentation resulted in biological removal of low molecular weight PAH in the reactors fed with primary sludge using all three approaches while clear biological removal of the medium- and high molecular weight PAH only was observed if the bacteria were added continuously (approach A2).
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Long term studies on the anaerobic biodegradability of MTBE and other gasoline ethers.
J. Hazard. Mater.
PUBLISHED: 04-03-2009
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Anaerobic biodegradation of methyl tert-butyl ether (MTBE) using electron acceptors such as nitrate, Fe(III), sulfate and bicarbonate, may be more cost effective and feasible compared to aerobic treatment methods, for dealing with the MTBE problem. Currently, there are a few reports in the literature which have documented anaerobic biodegradation of MTBE in batch studies. However, some of the reports have been controversial, additionally many other studies have failed to document anaerobic biodegradation. Experiments were conducted over a long term period in both batch and continuous reactors to investigate the anaerobic biodegradability of MTBE and other gasoline ethers. Inoculums collected from various environments were used, along with different electron acceptors. Only one set of the batch experiments showed a 30-60% conversion of MTBE to tert-butyl alcohol under Fe(III)-reducing conditions, using complexed Fe(III). The use of complexed Fe(III) created an initial low pH of 1-2 in these batches due to its acidic nature, therefore, the removal may be due to acid hydrolysis rather than biological processes. Based on the findings obtained, caution should be applied in the interpretation of experimental data in which complexed Fe(III) is used for bioremediation of MTBE.
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The kinetochore-bound Ska1 complex tracks depolymerizing microtubules and binds to curved protofilaments.
Dev. Cell
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To ensure equal chromosome segregation during mitosis, the macromolecular kinetochore must remain attached to depolymerizing microtubules, which drive chromosome movements. How kinetochores associate with depolymerizing microtubules, which undergo dramatic structural changes forming curved protofilaments, has yet to be defined in vertebrates. Here, we demonstrate that the conserved kinetochore-localized Ska1 complex tracks with depolymerizing microtubule ends and associates with both the microtubule lattice and curved protofilaments. In contrast, the Ndc80 complex, a central player in the kinetochore-microtubule interface, binds only to the straight microtubule lattice and lacks tracking activity. We demonstrate that the Ska1 complex imparts its tracking capability to the Ndc80 complex. Finally, we present a structure of the Ska1 microtubule-binding domain that reveals its interaction with microtubules and its regulation by Aurora B. This work defines an integrated kinetochore-microtubule interface formed by the Ska1 and Ndc80 complexes that associates with depolymerizing microtubules, potentially by interacting with curved microtubule protofilaments.
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Provision of an explanation for the inefficacy of immunotherapy in sporadic inclusion body myositis: quantitative assessment of inflammation and ?-amyloid in the muscle.
Arthritis Rheum.
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In sporadic inclusion body myositis (IBM), inflammation and accumulation of ?-amyloid-associated molecules cause muscle fiber damage. We undertook this study to determine why intravenous immunoglobulin (IVIG) and prednisone are not effective in sporadic IBM despite their effectiveness in other inflammatory myopathies.
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Biomimetic synthesis and proposal of relative and absolute stereochemistry of heronapyrrole C.
Org. Lett.
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The first synthesis of (-)-heronapyrrole C, the enantiomer of a unique farnesylated 2-nitropyrrole natural product is described. With none of the chiral centers of heronapyrrole C originally assigned, we proposed the most likely natural configuration on the basis of a putative biosynthetic pathway. The key step of the synthesis is a biomimetic polyepoxide cyclization cascade to establish the bis-THF moiety. Thus, (-)-heronapyrrole C is synthesized in eight steps from commercially available starting materials.
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Hemorheological risk factors of acute chest syndrome and painful vaso-occlusive crisis in children with sickle cell disease.
Haematologica
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Little is known about the effects of blood rheology on the occurrence of acute chest syndrome and painful vaso-occlusive crises in children with sickle cell anemia and hemoglobin SC disease.
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Nitric oxide stress in sporadic inclusion body myositis muscle fibres: inhibition of inducible nitric oxide synthase prevents interleukin-1?-induced accumulation of ?-amyloid and cell death.
Brain
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Sporadic inclusion body myositis is a severely disabling myopathy. The design of effective treatment strategies is hampered by insufficient understanding of the complex disease pathology. Particularly, the nature of interrelationships between inflammatory and degenerative pathomechanisms in sporadic inclusion body myositis has remained elusive. In Alzheimers dementia, accumulation of ?-amyloid has been shown to be associated with upregulation of nitric oxide. Using quantitative polymerase chain reaction, an overexpression of inducible nitric oxide synthase was observed in five out of ten patients with sporadic inclusion body myositis, two of eleven with dermatomyositis, three of eight with polymyositis, two of nine with muscular dystrophy and two of ten non-myopathic controls. Immunohistochemistry confirmed protein expression of inducible nitric oxide synthase and demonstrated intracellular nitration of tyrosine, an indicator for intra-fibre production of nitric oxide, in sporadic inclusion body myositis muscle samples, but much less in dermatomyositis or polymyositis, hardly in dystrophic muscle and not in non-myopathic controls. Using fluorescent double-labelling immunohistochemistry, a significant co-localization was observed in sporadic inclusion body myositis muscle between ?-amyloid, thioflavine-S and nitrotyrosine. In primary cultures of human myotubes and in myoblasts, exposure to interleukin-1? in combination with interferon-? induced a robust upregulation of inducible nitric oxide synthase messenger RNA. Using fluorescent detectors of reactive oxygen species and nitric oxide, dichlorofluorescein and diaminofluorescein, respectively, flow cytometry revealed that interleukin-1? combined with interferon-? induced intracellular production of nitric oxide, which was associated with necrotic cell death in muscle cells. Intracellular nitration of tyrosine was noted, which partly co-localized with amyloid precursor protein, but not with desmin. Pharmacological inhibition of inducible nitric oxide synthase by 1400W reduced intracellular production of nitric oxide and prevented accumulation of ?-amyloid, nitration of tyrosine as well as cell death inflicted by interleukin-1? combined with interferon-?. Collectively, these data suggest that, in skeletal muscle, inducible nitric oxide synthase is a central component of interactions between interleukin-1? and ?-amyloid, two of the most relevant molecules in sporadic inclusion body myositis. The data further our understanding of the pathology of sporadic inclusion body myositis and may point to novel treatment strategies.
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[Aorta-caval fistula as a complication to abdominal aorta aneurysm].
Ugeskr. Laeg.
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An 84 year-old man with a history of mild well-controlled hypertension was admitted acute with severe chest and epigastrial pains, radiation to the back and nausea lasting one hour under the diagnosis acute coronary syndrome. Acute computed tomography of the thorax and abdomen showed an 8 x 10 cm infrarenal abdominal aorta aneurysm with a 10 mm fistula through the wall of the aorta into the inferior caval vein.
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Motor performance of young dystrophic mdx mice treated with long-circulating prednisolone liposomes.
J. Neurosci. Res.
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For Duchenne muscular dystrophy (DMD), a common myopathy that leads to severe disability, no causal therapy is available. Glucocorticosteroids improve patients muscle strength, but their long-term use is limited by negative side effects. Thus, pharmacological modifications of glucocorticosteroids are required to increase the efficacy by drug targeting. Liposomal encapsulation augments systemic half-life and local tissue concentrations of glucocorticosteroids and, at the same time, reduces systemic side effects. In this study, the efficacy of novel, long-circulating, polyethylene-glycol-coated liposomes encapsulating prednisolone was compared with free prednisolone in the treatment of mdx mice, a well-established animal model for DMD. Using an objective and sensitive computerized 24-hr detection system of voluntary wheel-running in single cages, we demonstrate a significant impairment of the running performance in mdx compared with black/10 control mice aged 3-6 weeks. Treatment with liposomal or free prednisolone did not improve running performance compared with saline control or empty liposomes. Histopathological parameters, including the rate of internalized nuclei and fiber size variation, and mRNA and protein expression levels of transforming growth factor (TGF)-? and monocytes chemotactic protein (MCP)-1 also remained unchanged. Bioactivity in skeletal muscle of liposomal and free prednisolone was demonstrated by elevated mRNA expression of muscle ring finger protein 1 (MuRF1), a mediator of muscle atrophy, and its forkhead box transcription factors (Foxo1/3). Our data support the assessment of voluntary running to be a robust and reproducible outcome measure of skeletal muscle performance during the early disease course of mdx mice and suggest that liposomal encapsulation is not superior in treatment efficacy compared with conventional prednisolone. Our study helps to improve the future design of experimental treatment in animal models of neuromuscular diseases.
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Synthetic Endeavors Towards 2-Nitro-4-Alkyl-Pyrroles in the Context of the Total Synthesis of Heronapyrrole C and Preparation of a Carboxylate Natural Product Analogue.
J. Org. Chem.
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The synthesis of 2-nitro-4-oligoprenyl substituted pyrrole derivatives relevant to the heronapyrroles and related natural products was investigated. Among numerous approaches nitration of a 3-farnesyl-substituted unprotected pyrrole using AcONO2 gave best results, albeit still with unsatisfactory yield and regioselectivity. Therefore, the synthesis of (-)-heronapyrrole C acid, an analogue of the naturally occurring antibiotic heronapyrrole C, carrying a bioisosteric carboxylate in place of the nitro group was examined. In lieu of the unsatisfactory nitration a regioselective acylation with Cl3CCOCl was carried out (> 8:1 regioselectivity; in contrast to the 1:1.3 ratio for the nitration). The trichloromethyl ketone was converted to the desired acid in a haloform reaction at the final stage of the synthesis. Further key steps of the analogue synthesis involved a position- and stereoselective Corey-Noe-Lin-dihydroxylation and an organocatalytic double Shi-epoxidation. A biomimetic polyepoxide cyclization cascade established the bis-THF backbone. Thus, (-)-heronapyrrole C acid was synthesized in 8 steps (14.5% overall yield) from commercially available starting materials.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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