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Find video protocols related to scientific articles indexed in Pubmed.
Au36(SPh)24 Nanomolecules: X-ray Crystal Structure, Optical Spectroscopy, Electrochemistry, and Theoretical Analysis.
J Phys Chem B
PUBLISHED: 10-16-2014
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The physicochemical properties of gold:thiolate nanomolecules depend on their crystal structure and the capping ligands. The effects of protecting ligands on the crystal structure of the nanomolecules are of high interest in this area of research. Here we report the crystal structure of an all aromatic thiophenolate-capped Au36(SPh)24 nanomolecule, which has a face-centered cubic (fcc) core similar to other nanomolecules such as Au36(SPh-tBu)24 and Au36(SC5H9)24 with the same number of gold atoms and ligands. The results support the idea that a stable core remains intact even when the capping ligand is varied. We also correct our earlier assignment of "Au36(SPh)23" which was determined based on MALDI mass spectrometry which is more prone to fragmentation than ESI mass spectrometry. We show that ESI mass spectrometry gives the correct assignment of Au36(SPh)24, supporting the X-ray crystal structure. The electronic structure of the title compound was computed at different levels of theory (PBE, LDA, and LB94) using the coordinates extracted from the single crystal X-ray diffraction data. The optical and electrochemical properties were determined from experimental data using UV-vis spectroscopy, cyclic voltammetry, and differential pulse voltammetry. Au36(SPh)24 shows a broad electrochemical gap near 2 V, a desirable optical gap of ?1.75 eV for dye-sensitized solar cell applications, as well as appropriately positioned electrochemical potentials for many electrocatalytic reactions.
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Ophthalmologic Pathology: SY20-2 WHAT IS YOUR DIAGNOSIS?
Pathology
PUBLISHED: 09-05-2014
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Leiomyosarcoma is a malignant smooth-muscle tumor having a predilection for the female genital and gastrointestinal tracts. Although few cases of orbital metastases of leiomyosarcoma have been reported in literature, primary leiomyosarcoma involving the ocular structures is extremely rare. We report a case of primary orbital leiomyosarcoma in a 21-year-old, African male who presented with progressive proptosis and pain.
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Long-term Survival and Late Effects among 1-year Survivors of Second Allogeneic Hematopoietic Cell Transplantation for Relapsed Acute Leukemia and Myelodysplastic Syndromes.
Biol. Blood Marrow Transplant.
PUBLISHED: 08-19-2014
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We analyzed the outcomes of patients who survived disease-free for 1-year or more following second allogeneic hematopoietic cell transplantation (HCT) for relapsed acute leukemia or myelodysplastic syndromes between 1980 and 2009. A total of 1285 patients received a second allogeneic transplant following disease relapse; among these 325 survived relapse-free at 1-year after the second HCT. The median time from first to second HCT was 17 and 24 months for children and adults, respectively. A myeloablative preparative regimen was used in the second transplant in 62% of children and 45% of adult patients. The overall 10-year conditional survival rates after second transplantation in this cohort of patients who had survived disease-free for at least one year were 55% in children and 39% in adults. Relapse was the leading cause of mortality (77% and 54% of deaths in children and adults, respectively). In multivariate analyses, only disease status prior to second HCT was significantly associated with higher risk for overall mortality (HR 1.71 for patients with disease not in complete remission prior to second HCT, P<0.01). Chronic graft-versus-host disease (GVHD) developed in 43% and 75% of children and adults following second transplant. Chronic GVHD was the leading cause of non-relapse mortality followed by organ failure and infection. The cumulative incidence of developing at least one of the studied late effects at 10-years after second HCT was 63% in children and 55% in adults. The most frequent late effects in children were growth disturbance (10-year cumulative incidence 22%) and cataracts (20%), and in adults were cataracts (20%) and avascular necrosis (13%). Among patients with acute leukemia and myelodysplastic syndromes who receive a second allogeneic HCT for relapse and survive disease-free for at least 1-year, many can be expected to survive long term. However, they continue to be at risk for relapse and non-relapse morbidity and mortality. Novel approaches are needed to minimize relapse risk and long-term transplant morbidity in this population.
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Maternal supplementation of ?-linolenic acid in normal and protein-restricted diets modulate lipid metabolism, adipose tissue growth and leptin levels in the suckling offspring.
Eur J Nutr
PUBLISHED: 08-11-2014
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Lipid quantity and quality have been shown to affect serum cholesterol, adipose and serum leptin levels during prenatal and postnatal dietary supplementation of adult rats. Maternal protein deficiency during pregnancy and lactation also affects polyunsaturated fatty acid (PUFA) levels in the offspring. The aim of the present study was to analyze the effect of ?-linolenic acid (ALA; n-3) on n-3 PUFA accretion, lipid profile, leptin levels and adipose growth in normal and protein-restricted (deficient) dams and their suckling pups.
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Structures and organization of adenovirus cement proteins provide insights into the role of capsid maturation in virus entry and infection.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 07-28-2014
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Adenovirus cement proteins play crucial roles in virion assembly, disassembly, cell entry, and infection. Based on a refined crystal structure of the adenovirus virion at 3.8-Å resolution, we have determined the structures of all of the cement proteins (IIIa, VI, VIII, and IX) and their organization in two distinct layers. We have significantly revised the recent cryoelectron microscopy models for proteins IIIa and IX and show that both are located on the capsid exterior. Together, the cement proteins exclusively stabilize the hexon shell, thus rendering penton vertices the weakest links of the adenovirus capsid. We describe, for the first time to our knowledge, the structure of protein VI, a key membrane-lytic molecule, and unveil its associations with VIII and core protein V, which together glue peripentonal hexons beneath the vertex region and connect them to the rest of the capsid on the interior. Following virion maturation, the cleaved N-terminal propeptide of VI is observed, reaching deep into the peripentonal hexon cavity, detached from the membrane-lytic domain, so that the latter can be released. Our results thus provide the molecular basis for the requirement of maturation cleavage of protein VI. This process is essential for untethering and release of the membrane-lytic region, which is known to mediate endosome rupture and delivery of partially disassembled virions into the host cell cytoplasm.
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Au???(SR)?? nanomolecules: composition, optical spectroscopy, electrochemistry and electrocatalytic reduction of CO?.
Chem. Commun. (Camb.)
PUBLISHED: 07-17-2014
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Au137(SR)56, a nanomolecule with a precise number of metal atoms and ligands, was synthesized. The composition was confirmed by MALDI and ESI mass spectrometry using three unique ligands (-SCH2CH2Ph, -SC6H13, and -SC4H9) and nano-alloys with Ag and Pd. The electrocatalytic properties were tested for CO2 reduction.
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Orbital alveolar soft-part sarcoma: clinico-pathological profiles, management and outcomes.
J Cancer Res Ther
PUBLISHED: 07-16-2014
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To study the clinico-radiological and clinic-pathological features of orbital alveolar soft-part sarcomas (ASPS).
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Investigation of Cardiovascular Effects of Tetrahydro-?-carboline sstr3 antagonists.
ACS Med Chem Lett
PUBLISHED: 07-10-2014
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Antagonism of somatostatin subtype receptor 3 (sstr3) has emerged as a potential treatment of Type 2 diabetes. Unfortunately, the development of our first preclinical candidate, MK-4256, was discontinued due to a dose-dependent QTc (QT interval corrected for heart rate) prolongation observed in a conscious cardiovascular (CV) dog model. As the fate of the entire program rested on resolving this issue, it was imperative to determine whether the observed QTc prolongation was associated with hERG channel (the protein encoded by the human Ether-à-go-go-Related Gene) binding or was mechanism-based as a result of antagonizing sstr3. We investigated a structural series containing carboxylic acids to reduce the putative hERG off-target activity. A key tool compound, 3A, was identified from this SAR effort. As a potent sstr3 antagonist, 3A was shown to reduce glucose excursion in a mouse oGTT assay. Consistent with its minimal hERG activity from in vitro assays, 3A elicited little to no effect in an anesthetized, vagus-intact CV dog model at high plasma drug levels. These results afforded the critical conclusion that sstr3 antagonism is not responsible for the QTc effects and therefore cleared a path for the program to progress.
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Synthesis of Au130(SR)50 and Au(130-x)Ag(x)(SR)50 nanomolecules through core size conversion of larger metal clusters.
Phys Chem Chem Phys
PUBLISHED: 04-16-2014
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Gold nanomolecules with a precise number of metal atoms and thiolate ligands are being used for catalysis, biosensing, drug delivery and as alternative energy sources. Highly monodisperse products, with reproducible synthesis and complete characterization, are essential for these purposes. Post synthetic etching is used to synthesize highly stable gold nanomolecules. We report a synthetic protocol for the scalable synthesis of Au130(SR)50 for the first time, by etching of larger clusters via a core conversion process. Au130(SR)50 is not present in the crude product, but, is exclusively formed by etching larger clusters (>40 kDa). This is the first evidence that larger nanocluster cores convert to Au130(SR)50. The special stability of Au130(SR)50 is confirmed by the formation of Au130-x(metal)x(SR)50, where R = CH2CH2Ph, C6H13, C12H25 and metal = Ag, Pd. AuxAg130-x(SR)50 is isolated and characterized with two different Au?:?Ag precursor ratios. Upon alloying there is a change in the optical features of this 130-metal atom nanomolecule. To understand the process of etching and core conversion, a possible mechanism is being proposed. Highly stable nanomolecules like this can find potential applications in high temperature catalysis and sensing.
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eSNaPD: a versatile, web-based bioinformatics platform for surveying and mining natural product biosynthetic diversity from metagenomes.
Chem. Biol.
PUBLISHED: 04-14-2014
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Environmental Surveyor of Natural Product Diversity (eSNaPD) is a web-based bioinformatics and data aggregation platform that aids in the discovery of gene clusters encoding both novel natural products and new congeners of medicinally relevant natural products using (meta)genomic sequence data. Using PCR-generated sequence tags, the eSNaPD data-analysis pipeline profiles biosynthetic diversity hidden within (meta)genomes by comparing sequence tags to a reference data set of characterized gene clusters. Sample mapping, molecule discovery, library mapping, and new clade visualization modules facilitate the interrogation of large (meta)genomic sequence data sets for diverse downstream analyses, including, but not limited to, the identification of environments rich in untapped biosynthetic diversity, targeted molecule discovery efforts, and chemical ecology studies. eSNaPD is designed to generate a global atlas of biosynthetic diversity that can facilitate a systematic, sequence-based interrogation of nature's biosynthetic potential.
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Application of chimeric mice with humanized liver for study of human-specific drug metabolism.
Drug Metab. Dispos.
PUBLISHED: 04-03-2014
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Human-specific or disproportionately abundant human metabolites of drug candidates that are not adequately formed and qualified in preclinical safety assessment species pose an important drug development challenge. Furthermore, the overall metabolic profile of drug candidates in humans is an important determinant of their drug-drug interaction susceptibility. These risks can be effectively assessed and/or mitigated if human metabolic profile of the drug candidate could reliably be determined in early development. However, currently available in vitro human models (e.g., liver microsomes, hepatocytes) are often inadequate in this regard. Furthermore, the conduct of definitive radiolabeled human ADME studies is an expensive and time-consuming endeavor that is more suited for later in development when the risk of failure has been reduced. We evaluated a recently developed chimeric mouse model with humanized liver on uPA/SCID background for its ability to predict human disposition of four model drugs (lamotrigine, diclofenac, MRK-A, and propafenone) that are known to exhibit human-specific metabolism. The results from these studies demonstrate that chimeric mice were able to reproduce the human-specific metabolite profile for lamotrigine, diclofenac, and MRK-A. In the case of propafenone, however, the human-specific metabolism was not detected as a predominant pathway, and the metabolite profiles in native and humanized mice were similar; this was attributed to the presence of residual highly active propafenone-metabolizing mouse enzymes in chimeric mice. Overall, the data indicate that the chimeric mice with humanized liver have the potential to be a useful tool for the prediction of human-specific metabolism of xenobiotics and warrant further investigation.
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Quantized double layer charging of Au130(SR)50 nanomolecules.
Analyst
PUBLISHED: 03-08-2014
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Quantized double layer (QDL) charging of a Au130(SR)50 nanomolecule is reported for the first time. In the past, QDL charging was known only for Au144(SR)60 and Au225(SR)75 nanomolecules, which intrigued much research in this field. Here, using differential pulse voltammetry, we demonstrate that Au130 shows QDL charging. Furthermore, 13 different oxidation-reduction waves corresponding to single electron charging events with a clear electrochemical gap of ? 450 mV are reported. For Au130(SR)50, both the QDL behaviour and electrochemical gap were observed. Considering the charging energy, the HOMO-LUMO gap of the nanomolecule is 200 mV. Further data analysis was performed to find the capacitance of Au130(SR)50. A comprehensive comparison with other magic sized nanomolecules was made to confirm the molecule-like to bulk metal transition with increasing size of gold nanomolecules. Gold nanomolecules with these electrochemical properties are of great interest in the field of catalysis.
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Adenovirus composition, proteolysis, and disassembly studied by in-depth qualitative and quantitative proteomics.
J. Biol. Chem.
PUBLISHED: 03-03-2014
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Using high-resolution MS-based proteomics in combination with multiple protease digestion, we profiled, with on average 90% sequence coverage, all 13 viral proteins present in an human adenovirus (HAdV) vector. This in-depth profile provided multiple peptide-based evidence on intrinsic protease activity affecting several HAdV proteins. Next, the generated peptide library was used to develop a targeted proteomics method using selected reaction monitoring (SRM) aimed at quantitative profiling of the stoichiometry of all 13 proteins present in the HAdV. We also used this method to probe the release of specific virus proteins initiated by thermal stimulation, mimicking the early stage of HAdV disassembly during entry into host cells. We confirmed the copy numbers of the most well characterized viral capsid components and established the copy numbers for proteins whose stoichiometry has so far not been accurately defined. We also found that heating HAdV induces the complete release of the penton base and fiber proteins as well as a substantial release of protein VIII and VI. For these latter proteins, maturational proteolysis by the adenoviral protease leads to the differential release of fragments with certain peptides being fully released and others largely retained in the AdV particles. This information is likely to be beneficial for the ongoing interpretation of high resolution cryoEM and x-ray electron density maps.
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Management and outcome of retinoblastoma with vitreous seeds.
Ophthalmology
PUBLISHED: 02-28-2014
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To report the treatment response of retinoblastoma with vitreous seeds to high-dose chemotherapy coupled with periocular carboplatin.
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Core size conversion: route for exclusive synthesis of Au38 or Au40 nanomolecules.
Langmuir
PUBLISHED: 02-27-2014
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Gold nanomolecules with a precise number of gold atoms and ligands have promise for catalytic, optical, and biomedical applications. For practical applications, it is essential to develop synthetic protocols to prepare monodisperse gold nanomolecules. A typical synthesis yields a number of nanomolecules with discrete numbers of core atoms. Thermochemical treatment in the presence of excess thiol, etching, is known to narrow down the number of discrete nanomolecules, by selective degradation of sizes with lower stability. Au38(SR)24 and Au40(SR)24 are abundantly formed in these etching reactions due to their extraordinary stability to chemical etching. These nanomolecules are of high interest due in part to its stability, X-ray crystallographic structure availability (Au38), and intrinsic chirality arising from the arrangement of the Au-SR interface. However, the synthetic routes typically yield a mixture of Au38 and Au40, demanding extensive separation protocols. Here, we present a synthetic route to prepare either Au38 or Au40 exclusively in the product of etching. This was made possible by conducting a comprehensive mechanistic study starting from single-sized reactant. Au67 on etching yields Au40 exclusively. Au(103-105)(SR)(45-46) on etching also yields Au40 exclusively. Clusters of various sizes smaller than Au67 on etching yield Au38 exclusively. This is the first direct evidence for the exclusive formation of Au38 and Au40 nanomolecules by core size conversion. Mass spectrometry was used to study the core size conversion reactions to understand the mechanism. Au38 and Au40 nanomolecules form via different intermediates, as observed in the mass spectrometry data.
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The cleaved N-terminus of pVI binds peripentonal hexons in mature adenovirus.
J. Mol. Biol.
PUBLISHED: 02-25-2014
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Mature human adenovirus particles contain four minor capsid proteins, in addition to the three major capsid proteins (penton base, hexon and fiber) and several proteins associated with the genomic core of the virion. Of the minor capsid proteins, VI plays several crucial roles in the infection cycle of the virus, including hexon nuclear targeting during assembly, activation of the adenovirus proteinase (AVP) during maturation and endosome escape following cell entry. VI is translated as a precursor (pVI) that is cleaved at both N- and C-termini by AVP. Whereas the role of the C-terminal fragment of pVI, pVIc, is well established as an important co-factor of AVP, the role of the N-terminal fragment, pVIn, is currently elusive. In fact, the fate of pVIn following proteolytic cleavage is completely unknown. Here, we use a combination of proteomics-based peptide identification, native mass spectrometry and hydrogen-deuterium exchange mass spectrometry to show that pVIn is associated with mature human adenovirus, where it binds at the base of peripentonal hexons in a pH-dependent manner. Our findings suggest a possible role for pVIn in targeting pVI to hexons for proper assembly of the virion and timely release of the membrane lytic mature VI molecule.
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Chemical-biogeographic survey of secondary metabolism in soil.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 02-18-2014
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In this study, we compare biosynthetic gene richness and diversity of 96 soil microbiomes from diverse environments found throughout the southwestern and northeastern regions of the United States. The 454-pyroseqencing of nonribosomal peptide adenylation (AD) and polyketide ketosynthase (KS) domain fragments amplified from these microbiomes provide a means to evaluate the variation of secondary metabolite biosynthetic diversity in different soil environments. Through soil composition and AD- and KS-amplicon richness analysis, we identify soil types with elevated biosynthetic potential. In general, arid soils show the richest observed biosynthetic diversity, whereas brackish sediments and pine forest soils show the least. By mapping individual environmental amplicon sequences to sequences derived from functionally characterized biosynthetic gene clusters, we identified conserved soil type-specific secondary metabolome enrichment patterns despite significant sample-to-sample sequence variation. These data are used to create chemical biogeographic distribution maps for biomedically valuable families of natural products in the environment that should prove useful for directing the discovery of bioactive natural products in the future.
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Estrogen receptor coregulators and pioneer factors: the orchestrators of mammary gland cell fate and development.
Front Cell Dev Biol
PUBLISHED: 01-01-2014
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The steroid hormone, 17?-estradiol (E2), plays critical role in various cellular processes such as cell proliferation, differentiation, migration and apoptosis, and is essential for reproduction and mammary gland development. E2 actions are mediated by two classical nuclear hormone receptors, estrogen receptor ? and ? (ERs). The activity of ERs depends on the coordinated activity of ligand binding, post-translational modifications (PTMs), and importantly the interaction with their partner proteins called "coregulators." Because coregulators are proved to be crucial for ER transcriptional activity, and majority of breast cancers are ER? positive, an increased interest in the field has led to the identification of a large number of coregulators. In the last decade, gene knockout studies using mouse models provided impetus to our further understanding of the role of these coregulators in mammary gland development. Several coregulators appear to be critical for terminal end bud (TEB) formation, ductal branching and alveologenesis during mammary gland development. The emerging studies support that, coregulators along with the other ER partner proteins called "pioneer factors" together contribute significantly to E2 signaling and mammary cell fate. This review discusses emerging themes in coregulator and pioneer factor mediated action on ER functions, in particular their role in mammary gland cell fate and development.
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Au103(SR)45, Au104(SR)45, Au104(SR)46 and Au105(SR)46 nanoclusters.
Nanoscale
PUBLISHED: 10-18-2013
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High resolution ESI mass spectrometry of the "22 kDa" nanocluster reveals the presence of a mixture containing Au103(SR)45, Au104(SR)45, Au104(SR)46, and Au105(SR)46 nanoclusters, where R = -CH2CH2Ph. MALDI TOF MS data confirm the purity of the sample and a UV-vis spectrum shows minor features. Au102(SC6H5COOH)44, whose XRD crystal structure was recently reported, is not observed. This is due to ligand effects, because the 102?:?44 composition is produced using aromatic ligands. However, the 103-, 104- and 105-atom nanoclusters, protected by -SCH2CH2Ph and -SC6H13 ligands, are at or near 58 electron shell closing.
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Lymphatic absorption, metabolism, and excretion of a therapeutic peptide in dogs and rats.
Drug Metab. Dispos.
PUBLISHED: 10-02-2013
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The objective of the current study was to evaluate the mechanism of absorption and metabolism of a PEGylated peptide, MRL-1 (46 kDa), after s.c. dosing in dogs and rats. Thoracic lymph duct-cannulated (LDC) dog and rat models were developed that allowed continuous collection of lymph for up to 8 days. When [(3)H]MRL-1 was administered s.c. to LDC dogs, ?73% of the administered radioactivity was recovered in pooled lymph over a period of 120 hours, suggesting that lymphatic uptake is the major pathway of s.c. absorption for this peptide. In agreement with these data, the systemic exposure of radioactivity related to [(3)H]MRL-1 in LDC dogs was decreased proportionately when compared with that in noncannulated control dogs. After i.v. dosing with [(3)H]MRL-1 in LDC dogs, 20% of the administered radioactivity was recovered in pooled lymph over 168 hours, suggesting some level of recirculation of radioactivity related to [(3)H]MRL-1 from the plasma compartment into the lymphatic system. Experiments conducted in the LDC rat model also resulted in similar conclusions. Analysis of injection site s.c. tissue showed significant metabolism of [(3)H]MRL-1, which provides an explanation for the <100% bioavailability of therapeutic proteins and peptides after s.c. dosing. After s.c. dosing, the major circulating components in plasma were the parent peptide and the PEG-linker [(3)H]MRL-2. The metabolism profiles in lymph were similar to those in plasma, suggesting that the loss of peptide was minimal during lymphatic transport. After i.v. dosing in rats, [(3)H]MRL-1 was metabolized and excreted primarily in the urine as metabolites.
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Establishment of norms of the beta angle to assess the sagittal discrepancy for Nellore district population.
J Nat Sci Biol Med
PUBLISHED: 10-02-2013
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In orthodontic diagnosis and treatment planning, assessment of anteroposterior discrepancy is of importance to the orthodontist. Both angular and linear measurements have been incorporated into various cephalometric analyses to help the clinician diagnose anteroposterior discrepancies and establish the most appropriate treatment plan. Hence the present study is designed to establish the norms of Beta angle to assess the sagittal discrepancy for Nellore district population.
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Amino acid substitution at peptide-binding pockets of HLA class I molecules increases risk of severe acute GVHD and mortality.
Blood
PUBLISHED: 08-27-2013
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HLA disparity has a negative impact on the outcomes of hematopoietic cell transplantation (HCT). We studied the independent impact of amino acid substitution (AAS) at peptide-binding positions 9, 99, 116, and 156, and killer immunoglobulin-like receptor binding position 77 of HLA-A, B, or C, on the risks for grade 3-4 acute graft-versus-host disease (GVHD), chronic GVHD, treatment-related mortality (TRM), relapse, and overall survival. In multivariate analysis, a mismatch at HLA-C position 116 was associated with increased risk for severe acute GVHD (hazard ratio [HR] = 1.45, 95% confidence interval [CI] = 1.15-1.82, P = .0016). Mismatch at HLA-C position 99 was associated with increased transplant-related mortality (HR = 1.37, 95% CI = 1.1-1.69, P = .0038). Mismatch at HLA-B position 9 was associated with increased chronic GVHD (HR = 2.28, 95% CI = 1.36-3.82, P = .0018). No AAS were significantly associated with outcome at HLA-A. Specific AAS pair combinations with a frequency >30 were tested for association with HCT outcomes. Cysteine to tyrosine substitution at position 99 of HLA-C was associated with increased TRM (HR = 1.78, 95% = CI 1.27-2.51, P = .0009). These results demonstrate that donor-recipient mismatch for certain peptide-binding residues of the HLA class I molecule is associated with increased risk for acute and chronic GVHD and death.
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Mapping gene clusters within arrayed metagenomic libraries to expand the structural diversity of biomedically relevant natural products.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 07-03-2013
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Complex microbial ecosystems contain large reservoirs of unexplored biosynthetic diversity. Here we provide an experimental framework and data analysis tool to facilitate the targeted discovery of natural-product biosynthetic gene clusters from the environment. Multiplex sequencing of barcoded PCR amplicons is followed by sequence similarity directed data parsing to identify sequences bearing close resemblance to biosynthetically or biomedically interesting gene clusters. Amplicons are then mapped onto arrayed metagenomic libraries to guide the recovery of targeted gene clusters. When applied to adenylation- and ketosynthase-domain amplicons derived from saturating soil DNA libraries, our analysis pipeline led to the recovery of biosynthetic clusters predicted to encode for previously uncharacterized glycopeptide- and lipopeptide-like antibiotics; thiocoraline-, azinomycin-, and bleomycin-like antitumor agents; and a rapamycin-like immunosuppressant. The utility of the approach is demonstrated by using recovered eDNA sequences to generate glycopeptide derivatives. The experiments described here constitute a systematic interrogation of a soil metagenome for gene clusters capable of encoding naturally occurring derivatives of biomedically relevant natural products. Our results show that previously undetected biosynthetic gene clusters with potential biomedical relevance are very common in the environment. This general process should permit the routine screening of environmental samples for gene clusters capable of encoding the systematic expansion of the structural diversity seen in biomedically relevant families of natural products.
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PATIENT EDUCATION AND CARE FOR PERITONEAL DIALYSIS CATHETER PLACEMENT: A QUALITY IMPROVEMENT STUDY.
Perit Dial Int
PUBLISHED: 07-01-2013
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Background and OBJECTIVES: Peritoneal dialysis catheter (PDC) complications are an important barrier to peritoneal dialysis (PD) utilization. Practice guidelines for PDC placement exist, but it is unknown if these recommendations are followed. We performed a quality improvement study to investigate this issue.
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A simple mini-screw assembly for simultaneous molar uprighting and distalization--a case of adjunctive adult orthodontics.
Int J Orthod Milwaukee
PUBLISHED: 06-05-2013
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Anchorage is a major concern in adult mutilated dentition. However, with the explosive development of Temporary Anchorage Devices (TADs) newer avenues in orthodontic treatment philosophy have opened up. Mini-screws are found to be stable during such treatments, demonstrating that they could provide absolute anchorage for tooth movement. The present article describes a simple, yet effective technique for simultaneous molar uprighting and distalization, using direct skeletal anchorage using a mini-screw supported assembly in a 38 years old male patient as part of adjunctive adult orthodontics with mutilated dentition.
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Circummandibular wiring of symphysis fracture in a five-year-old child.
Case Rep Dent
PUBLISHED: 05-11-2013
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The treatment of pediatric maxillofacial fractures is unique due to the psychological, physiological, developmental, and anatomical characteristics of children. Method. This case report describes the management of symphysis fracture of mandible in a 5-year-old boy. The fracture was treated by acrylic splint with circummandibular wiring. Results. The splint was removed after 3 weeks. The patient had no complaints, and radiograph revealed a healed fracture. Conclusion. The clinical outcome in the present case indicates the management of mandibular fractures in pediatric patients using acrylic splint with circummandibular wiring.
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Adenoid cystic carcinoma of the lacrimal gland: role of nuclear survivin (BIRC5) as a prognostic marker.
Histopathology
PUBLISHED: 04-25-2013
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This study aimed to evaluate the expression of nuclear survivin in adenoid cystic carcinoma (ACC) of the lacrimal gland and to determine if this expression is associated with histopathological features, markers of apoptosis and proliferation or clinical outcomes.
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Distant metastatic retinoblastoma without central nervous system involvement.
Indian J Ophthalmol
PUBLISHED: 04-04-2013
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Retinoblastoma is the most common intraocular malignancy in children, with a reported incidence ranging from 1 in 15,000 to 1 in 18,000 live births. Metastatic retinoblastoma is rare in developed countries, with a reported range from 4.8% in the United States to 5.8% in the United Kingdom. However, the frequency reported from developing countries varies from 9 to 11% at presentation. The mortality is very high owing to late presentations, delayed diagnosis compounded by socio-economic factors. The management of metastatic retinoblastoma is evolving, but it is still a challenge in pediatric oncology. We present a case of an extensive skeletal metastasis that initially presented as a massive orbital retinoblastoma.
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Primary intraocular malignant extrarenal rhabdoid tumor: a clinicopathological correlation.
J Pediatr Ophthalmol Strabismus
PUBLISHED: 03-04-2013
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Malignant extrarenal rhabdoid tumor is a rare and highly aggressive tumor of childhood. Intraocular involvement by malignant extrarenal rhabdoid tumor has only been described once as a metastasis. No report exists in published literature describing a primary intraocular malignant extrarenal rhabdoid tumor. The authors report the first such case along with its clinico-radiological features and histopathologic and electron microscopic characteristics.
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Malignant teratoid ciliary body medulloepithelioma in a neonate.
J Pediatr Ophthalmol Strabismus
PUBLISHED: 02-28-2013
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Ciliary body medulloepithelioma is an intraocular tumor manifesting in early childhood, rarely at birth. A unique case of intraocular malignant teratoid ciliary body medulloepithelioma in a neonate presenting as buphthalmos at birth is reported. There was rapid progression with extraocular extension within 2 months and developed regional lymph node metastasis despite enucleation. The child underwent lymph node dissection and local radiotherapy with complete remission. [J Pediatr Ophthalmol Strabismus 2013;50:e37-e40.].
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Birth order and transplantation outcome in HLA-identical sibling stem cell transplantation: an analysis on behalf of the Center for International Blood and Marrow Transplantation.
Biol. Blood Marrow Transplant.
PUBLISHED: 01-25-2013
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Allogeneic stem cell transplantation (SCT) is the most effective treatment option for many hematologic malignancies, but graft-versus-host disease (GVHD) remains a major cause of treatment failure. Along with well-established risk factors for transplantation outcomes, recent single-center studies have identified a birth order effect in HLA-identical sibling SCT, with lower rates of acute and chronic GVHD and improved overall survival when the donor is younger than the recipient. One hypothesized mechanism for this effect is microchimerism due to fetomaternal and transmaternal sibling cell trafficking during pregnancy as the donor is exposed to recipient antigens in utero. The aim of the present study was to validate previously reported single-center data in a large, multicenter cohort provided by the Center for International Blood and Marrow Transplantation. All adult and pediatric patients (n = 11,365) with a hematologic malignancy who underwent allogeneic SCT with a graft from an HLA-identical sibling donor between 1990 and 2007 were included. When donors were younger than recipients, there was a significantly lower rate of acute GVHD grade II-IV and chronic GVHD in children, as well as a lower rate of chronic GVHD in adolescents. However, the hypothesized overall positive effect of lower relapse and better survival when donors are younger than recipients was not observed. Our data suggest that if otherwise equally matched, a graft from a younger sibling may be superior to a graft from an older sibling for children and adolescents undergoing SCT.
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Derivative 11;22 (emanuel) syndrome: a case report and a review.
Case Rep Pediatr
PUBLISHED: 01-15-2013
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Emanuel syndrome (ES) is a rare anomaly characterized by a distinctive phenotype, consisting of characteristic facial dysmorphism, microcephaly, severe mental retardation, developmental delay, renal anomalies, congenital cardiac defects, and genital anomalies in boys. Here, we report a male neonate, with the classical features of Emanuel syndrome.
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Optic nerve meningeal hemangiopericytoma: a clinicopathologic case report.
Surv Ophthalmol
PUBLISHED: 01-04-2013
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A 36-year-old woman presented with progressive loss of vision in the left eye for 3 years, and rapid progression and painful protrusion of the eye for one month. Clinical evaluation revealed no light perception, severe proptosis and hypoglobus, optic atrophy, and optociliary shunt vessels. Orbital imaging showed a well-defined heterogeneous intraconal mass partially encasing the optic nerve. A clinical diagnosis of optic nerve sheath meningioma was made, and the tumor was completely excised along with enucleation, followed by postoperative adjuvant external beam radiotherapy. There was no local recurrence at 15 month follow-up. Histopathologically, the tumor was found to be arising from the optic nerve meninges with classical "stag-horn" pattern and abundant cellularity. Immunohistochemistry supported the histopathological diagnosis of hemangiopericytoma. Optic nerve meningeal hemangiopericytoma is extremely rare-only two such cases have been reported in the literature.
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Identification of adenovirus serotype 5 hexon regions that interact with scavenger receptors.
J. Virol.
PUBLISHED: 12-07-2011
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Most of an intravenous dose of species C adenovirus serotype 5 (Ad5) is destroyed by liver Kupffer cells. In contrast, another species C virus, Ad6, evades these cells to mediate more efficient liver gene delivery. Given that this difference in Kupffer cell interaction is mediated by the hypervariable (HVR) loops of the virus hexon protein, we genetically modified each of the seven HVRs of Ad5 with a cysteine residue to enable conditional blocking of these sites with polyethylene glycol (PEG). We show that these modifications do not affect in vitro virus transduction. In contrast, after intravenous injection, targeted PEGylation at HVRs 1, 2, 5, and 7 increased viral liver transduction up to 20-fold. Elimination or saturation of liver Kupffer cells did not significantly affect this increase in the liver transduction. In vitro, PEGylation blocked uptake of viruses via the Kupffer cell scavenger receptor SRA-II. These data suggest that HVRs 1, 2, 5, and 7 of Ad5 may be involved in Kupffer cell recognition and subsequent destruction. These data also demonstrate that this conditional genetic-chemical mutation strategy is a useful tool for investigating the interactions of viruses with host tissues.
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Interstaple dithiol cross-linking in Au25(SR)18 nanomolecules: a combined mass spectrometric and computational study.
J. Am. Chem. Soc.
PUBLISHED: 11-22-2011
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A systematic study of cross-linking chemistry of the Au(25)(SR)(18) nanomolecule by dithiols of varying chain length, HS-(CH(2))(n)-SH where n = 2, 3, 4, 5, and 6, is presented here. Monothiolated Au(25) has six [RSAuSRAuSR] staple motifs on its surface, and MALDI mass spectrometry data of the ligand exchanged clusters show that propane (C3) and butane (C4) dithiols have ideal chain lengths for interstaple cross-linking and that up to six C3 or C4 dithiols can be facilely exchanged onto the cluster surface. Propanedithiol predominately exchanges with two monothiols at a time, making cross-linking bridges, while butanedithiol can exchange with either one or two monothiols at a time. The extent of cross-linking can be controlled by the Au(25)(SR)(18) to dithiol ratio, the reaction time of ligand exchange, or the addition of a hydrophobic tail to the dithiol. MALDI MS suggests that during ethane (C2) dithiol exchange, two ethanedithiols become connected by a disulfide bond; this result is supported by density functional theory (DFT) prediction of the optimal chain length for the intrastaple coupling. Both optical absorption spectroscopy and DFT computations show that the electronic structure of the Au(25) nanomolecule retains its main features after exchange of up to eight monothiol ligands.
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Granulocyte-macrophage colony-stimulating factor increases the proportion of circulating dendritic cells after autologous but not after allogeneic hematopoietic stem cell transplantation.
Cytotherapy
PUBLISHED: 05-24-2011
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Granulocyte-macrophage (GM) colony-stimulating factor (CSF) has been used as an adjuvant in cancer immunotherapy. We tested the hypothesis that GM-CSF (Leukine(®); sargramostim) improves immune reconstitution after hematopoietic stem cell transplantation (HSCT) based on our prior in vitro work that demonstrated the pro-inflammatory effects of GM-CSF on dendritic cells (DC).
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Orbital retinoblastoma: where do we go from here?
J Cancer Res Ther
PUBLISHED: 05-07-2011
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Diagnosis of orbital retinoblastoma traditionally carries a dismal prognosis. Although its incidence is less in the developed countries, it continues to contribute to an epidemic of extraocular disease at diagnosis in the developing world. Orbital retinoblastoma encompasses a wide range of distinct clinical entities with varying tumor load. There are no standard treatment protocols as of now but the current preferred management is multimodal with a combination of initial high-dose chemotherapy, surgery, external beam radiotherapy and prolonged chemotherapy for 12 cycles. Though orbital retinoblastoma is a catastrophic event, rapid advances on many fronts, especially the genetic, makes the future appear brighter than what it is now. This review looks at all the new frontiers that are in store in the near as well as the distant future. Looking at the ever expanding horizons makes one believe of a definite hope that one day we will conquer this disease as we have conquered many others in the past.
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Progressive improvement in cutaneous and extracutaneous chronic graft-versus-host disease after a 24-week course of extracorporeal photopheresis--results of a crossover randomized study.
Biol. Blood Marrow Transplant.
PUBLISHED: 02-11-2011
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In a prior multicenter randomized controlled trial, we found that a 12-week course of extracorporeal photopheresis (ECP) plus standard immunosuppressive therapy resulted in several beneficial outcomes in patients with corticosteroid-refractory/intolerant/dependent chronic graft-versus-host disease (GVHD). Here, we report the results of an open-label crossover ECP study in 29 eligible participants randomized initially to the standard of care non-ECP (control) arm. Eligible for the crossover ECP study were control arm patients who either (1) had progression of cutaneous chronic GVHD (cGVHD), defined as >25% worsening from baseline as measured by the percent change in the total skin score (TSS) at any time, or (2) had less than 15% improvement in the TSS, or had a ?25% reduction in corticosteroid dose at week 12 of the initial study. ECP was administered 3 times during week 1, then twice weekly until week 12, followed by 2 treatments monthly until week 24. The median age of the study cohort was 43 (20-67) years and 90% had extensive cGVHD. The median months from onset of cGVHD to start of ECP were 26 (range: 4-79). Twenty-five of 29 patients (86%) completed the 24-week course of ECP. Complete or partial skin response at week 24 was noted in 9 patients (31%). The median percent of decrease in TSS from baseline to weeks 12 and 24 was -7.9 and -25.8, respectively. In 4 (17%) and 8 (33%) patients, a ?50% reduction in corticosteroid dose at weeks 12 and 24 was observed. Extracutaneous cGVHD response was highest in oral mucosa with 70% complete and partial resolution after week 24. In conclusion, progressive improvement in cutaneous and extracutaneous cGVHD was observed after a 24-week course of ECP in patients who previously had no clinical improvement or exhibited worsening of cGVHD while receiving standard immunosuppressive therapy alone in a randomized study. These results confirm previous findings and support the notion that prolonged ECP appears to be necessary for optimal therapeutic effects in corticosteroid-refractory cGVHD patients.
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Design of a novel pyrrolidine scaffold utilized in the discovery of potent and selective human ?3 adrenergic receptor agonists.
Bioorg. Med. Chem. Lett.
PUBLISHED: 11-09-2010
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A novel class of human ?(3)-adrenergic receptor agonists was designed in effort to improve selectivity and metabolic stability versus previous disclosed ?(3)-AR agonists. As observed, many of the ?(3)-AR agonists seem to need the acyclic ethanolamine core for agonist activity. We have synthesized derivatives that constrained this moiety by introduction of a pyrrolidine. This unique modification maintains human ?(3) functional potency with improved selectivity versus ancillary targets and also eliminates the possibility of the same oxidative metabolites formed from cleavage of the N-C bond of the ethanolamine. Compound 39 exhibited excellent functional ?(3) agonist potency across species with good pharmacokinetic properties in rat, dog, and rhesus monkeys. Early de-risking of this novel pyrrolidine core (44) via full AMES study supports further research into various new ?(3)-AR agonists containing the pyrrolidine moiety.
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Orbital retinoblastoma: Present status and future challenges - A review.
Saudi J Ophthalmol
PUBLISHED: 09-24-2010
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Orbital retinoblastoma is a catastrophic event traditionally carrying a dismal prognosis. Although its incidence is less in the developed countries it continues to be one of the major diagnosis at presentation in the developing world. Orbital retinoblastoma encompasses a wide range of distinct clinical entities with varying tumor load. There are no standard treatment protocols as of now but the current preferred management is multimodal with a combination of initial high-dose chemotherapy, surgery, external beam radiotherapy and prolonged chemotherapy for twelve cycles. In spite of progress on all fronts including surgical, medical, diagnostic, genetic and rehabilitative with improving survival rates, however, lack of access to medical facilities, lack of education about the need for early medical attention and cultural resistance to enucleation continue to contribute to an epidemic of extra ocular disease at diagnosis in the developing world. This review introduces the various terminologies used in the spectrum of orbital retinoblastoma, discusses in details the clinical aspects and management protocols, current status and the future directions.
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Crystal structure of human adenovirus at 3.5 A resolution.
Science
PUBLISHED: 08-28-2010
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Rational development of adenovirus vectors for therapeutic gene transfer is hampered by the lack of accurate structural information. Here, we report the x-ray structure at 3.5 angstrom resolution of the 150-megadalton adenovirus capsid containing nearly 1 million amino acids. We describe interactions between the major capsid protein (hexon) and several accessory molecules that stabilize the capsid. The virus structure also reveals an altered association between the penton base and the trimeric fiber protein, perhaps reflecting an early event in cell entry. The high-resolution structure provides a substantial advance toward understanding the assembly and cell entry mechanisms of a large double-stranded DNA virus and provides new opportunities for improving adenovirus-mediated gene transfer.
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Metabolism and excretion of [14C]taranabant, a cannabinoid-1 inverse agonist, in humans.
Xenobiotica
PUBLISHED: 08-21-2010
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Taranabant (N-[(1S,2S)-3-(4-chlorophenyl)-2-(3-cyanophenyl)-1-methylpropyl]-2-methyl-2-{[5-(trifluoromethyl)pyridin-2-yl]oxy}propanamide or MK-0364) is an orally active inverse agonist of the cannabinoid 1 (CB-1) receptor that was under development for the management of obesity. The metabolism and excretion of taranabant were investigated following a single oral dose of 5?mg/201 ?Ci [14C]taranabant to six healthy male subjects. The overall excretion recovery of the administered radioactivity was nearly quantitative (?92%), with the majority of the dose (?87%) excreted into faeces and a much smaller fraction (?5%) into urine. Taranabant was absorbed rapidly, with C(max) of radioactivity attained at 1-2-h postdose. The parent compound and its monohydroxylated metabolite, M1, were the major radioactive components circulating in plasma and comprised ?12-24% and 33-42%, respectively, of the plasma radioactivity for up to 48?h. A second monohydroxylated metabolite, designated as M1a, represented ?10-12% of the radioactivity in the 2- and 8-h postdose plasma profiles. Metabolite profiles of the faeces samples consisted mainly of the (unabsorbed) parent compound and multiple diastereomeric carboxylic acid derivatives derived from oxidation of the geminal methyl group of the parent compound and of the hydroxylated metabolite/s. These data suggest that, similar to rats and monkeys, taranabant is primarily eliminated in humans via oxidative metabolism and excretion of metabolites via the biliary/faecal route.
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Discovery of N-[(4R)-6-(4-chlorophenyl)-7-(2,4-dichlorophenyl)-2,2-dimethyl-3,4-dihydro-2H-pyrano[2,3-b]pyridin-4-yl]-5-methyl-1H-pyrazole-3-carboxamide (MK-5596) as a novel cannabinoid-1 receptor (CB1R) inverse agonist for the treatment of obesity.
J. Med. Chem.
PUBLISHED: 04-29-2010
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This paper describes the discovery of N-[(4R)-6-(4-chlorophenyl)-7-(2,4-dichlorophenyl)-2,2-dimethyl-3,4-dihydro-2H-pyrano[2,3-b]pyridin-4-yl]-5-methyl-1H-pyrazole-3-carboxamide (MK-5596, 12c) as a novel cannabinoid-1 receptor (CB1R) inverse agonist for the treatment of obesity. Structure-activity relationship (SAR) studies of lead compound 3, which had off-target hERG (human ether-a-go-go related gene) inhibition activity, led to the identification of several compounds that not only had attenuated hERG inhibition activity but also were subject to glucuronidation in vitro providing the potential for multiple metabolic clearance pathways. Among them, pyrazole 12c was found to be a highly selective CB1R inverse agonist that reduced body weight and food intake in a DIO (diet-induced obese) rat model through a CB1R-mediated mechanism. Although 12c was a substrate of P-glycoprotein (P-gp) transporter, its high in vivo efficacy in rodents, good pharmacokinetic properties in preclinical species, good safety margins, and its potential for a balanced metabolism profile in man allowed for the further evaluation of this compound in the clinic.
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RB1 gene mutations in retinoblastoma and its clinical correlation.
Saudi J Ophthalmol
PUBLISHED: 04-19-2010
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To find correlation between the type of mutations observed and the severity of the disease using multiple techniques like polymerase chain reactions (PCR), quantitative multiplex PCR, sequencing and RNA analysis.
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Spiritual absence and 1-year mortality after hematopoietic stem cell transplant.
Biol. Blood Marrow Transplant.
PUBLISHED: 03-03-2010
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Religiosity and spirituality have been associated with better survival in large epidemiologic studies. This study examined the relationship between spiritual absence and 1-year all-cause mortality in allogeneic hematopoietic stem cell transplant (HSCT) recipients. Depression and problematic compliance were examined as possible mediators of a significant spiritual absence-mortality relationship. Eighty-five adults (mean = 46.85 years old, SD = 11.90 years) undergoing evaluation for allogeneic HSCT had routine psychologie evaluation prior to HSCT admission. The Millon Behavioral Medicine Diagnostic was used to assess spiritual absence, depression, and problematic compliance, the psychosocial predictors of interest. Patient status at 1 year and survival time in days were abstracted from medical records. Cox regression analysis was used to examine the relationship between the psychosocial factors of interest and mortality after adjusting for relevant biobehavioral factors. Twenty-nine percent (n = 25) of participants died within 1 year of HSCT. After covarying for disease type, individuals with the highest spiritual absence and problematic compliance scores were significantly more likely to die 1-year post-HSCT (hazard ratio [HR] = 2.49, P = .043 and HR = 3.74, P = .029, respectively), particularly secondary to infection, sepsis, or graft-versus-host disease (GVHD) (HR = 4.56, P = .01 and HR = 5.61, P = .014), relative to those without elevations on these scales. Depression was not associated with 1-year mortality, and problematic compliance did not mediate the relationship between spiritual absence and mortality. These preliminary results suggest that both spiritual absence and problematic compliance may be associated with poorer survival following HSCT. Future research should examine these relations in a larger sample using a more comprehensive assessment of spirituality.
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Virtual screening and selection of drug-like compounds to block noggin interaction with bone morphogenetic proteins.
J. Mol. Graph. Model.
PUBLISHED: 01-13-2010
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Noggin is a major natural extracellular antagonist to bone morphogenetic proteins (BMPs) which binds to BMPs and blocks binding of them to BMP-specific receptors and thus negatively regulates BMP-induced osteoblastic differentiation. Bone morphogenetic proteins (BMPs) signal through heteromeric protein complexes composed of type I and type II serine/threonine kinase receptors. Preventing the BMP-2/noggin interaction will preserve free BMP-2 and enhance the efficacy of BMP-2 to induce bone formation. This work is an attempt to use the current understanding of BMP-2, and its interaction with its receptors and antagonist to design an inhibitor of BMP-2/noggin interaction with the goal of lowering the dose of BMP-2 required in clinical applications. The crystal structure of the BMP-7/noggin complex, the BMP-2/BMP receptor IA ectodomain complex and the extracellular domain of BMP receptor II monomer are known. We modeled the BMP-2 based on the structure of its homologue BMP-7 and its binding complex with noggin. We also modeled a complex of BMP-2/BMPRIA/BMPRII by modeling BMPRII and replacing ActRIIB in the BMP-2/BMPRIA/ActRIIB complex. We then identified the binding region of noggin with BMP-2 and the receptors with BMP-2. From the analysis of structures of these complexes and modeling we identified the key amino acids present in the entire interacting surfaces among these proteins that play important physiological role in the regulation of cell differentiation and bone metabolism. By in silico screening we selected and ranked several compounds that have high theoretical scores to bind to noggin to block BMP-noggin interaction.
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Quality of life as a key indicator of patient satisfaction and treatment compliance in people with type 2 diabetes mellitus in the IMPROVE study: a multicentre, open label, non-randomised, observational trial.
J Indian Med Assoc
PUBLISHED: 12-02-2009
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Diabetes is a debilitating chronic illness having multiple impacts on physical and mental well-being of patients. When treating chronic conditions like diabetes, psychosocial aspects and quality of life (QoL) have to be considered; however, these receive less attention due to various reasons. Patients with diabetic complications have increased levels of depression and decreased QoL This necessitates evaluating QoL of patient which now is used as a primary or secondary end point in clinical trials eg, Diab-MedSat QoL questionnaire used in diabetes. At some point all diabetic patients may require insulin to control hyperglycaemia and disease progression. The traditional insulin syringe and needle delivery system has been the principal barrier in the treatment of diabetes as it was not well accepted among the patients due to various reasons. A success over this approach has been pen like devices like FlexPen and Novopen3 which are becoming more popular than the conventional syringe-and-needles as they have several advantages like, easy to carry, use, maintain and also reduces administrative errors ensuring accurate doses are delivered. The objective of IMPROVE study is to evaluate the safety and effectiveness of biphasic insulin aspart (NovoMix 30) in normal clinical practice conditions, in India. This is an open label, non-randomised, non-interventional, observational, safety and effectiveness study in approximately 17,995 patients with type 2 diabetes mellitus. A cohort of Indian patients (n = 349) from all 4 geographical locations (North, West, East and South of India) were administered QoL instrument Diab-MedSat at baseline and 346 patients at final visit (n = 346) to assess their satisfaction with the treatment they received. The results were included in the final statistical analysis as additional outcome variables. The Diab-MedSat Novo Nordisk June 2004 English (UK) version is used. The Diab-MedSat has 21 items that need to be answered and it is scored as an overall score (all 21 items) as well as three subscale scores regarding burden (11 items), symptoms (5 items), efficacy (5 items). The complete analysis took into account all 21 items of Diab-MedSat questionnaire with their subscales. Analyses of the cohort showed higher patient satisfaction among the patients administered Diab-MedSat questionnaire from baseline (n = 349) to final visit (n = 346). The mean of overall score was 52.33 (baseline visit) versus 79.03 (final visit). The difference in the overall score and sub parameters like burden, symptoms and efficacy between the baseline and final visits were statistically significant (p-value < 0.001). The mean value of difference in overall score between the baseline visit and final visit was 26.73 +/- 20.83; while the difference for burden, symptoms and efficacy were respectively 27.86 +/- 20.81, 19.75 +/- 20.94 and 32.87 +/- 28.08. A fairly clear picture emerged that the use of biphasic insulin aspart resulted in improved QoL of the patients substantially. This is demonstrated in the results for all the parameters that were used like symptoms, efficacy and burden. The overall number of extremely satisfied patients had increased from 5.4% in the baseline visit to 91% in the final visit. This unambiguously proves that the satisfaction of patients on biphasic insulin aspart (NovoMix 30) is beyond question.
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Sebaceous carcinoma of the eyelid metastasizing to the lacrimal sac after 5 years.
Orbit
PUBLISHED: 10-31-2009
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Eyelid sebaceous carcinoma metastasizing to lacrimal sac is rare. A 65 year old female underwent excision with 5 mm margins and Cutler-beard reconstruction for a nodulo-ulcerative mass showing eyelash loss in the middle third of the right upper eyelid. Histopathology confirmed it to be sebaceous carcinoma with uninvolved margins. Five years after primary excision, the patient presented with persistent epiphora and mass in the ipsilateral lacrimal sac region. Repeat excision biopsy and conjunctival map biopsy confirmed recurrent sebaceous carcinoma of the lacrimal sac. Thirteen months after adjuvant radiotherapy to the orbit, the patient is alive and well with no loco-regional recurrence.
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Development and optimization of a cell-based assay for the selection of synthetic compounds that potentiate bone morphogenetic protein-2 activity.
Cell Biochem. Funct.
PUBLISHED: 10-29-2009
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The requirement of large amounts of the recombinant human bone morphogenetic protein-2 (BMP-2) produces a huge translational barrier for its routine clinical use due to high cost. This leads to an urgent need to develop alternative methods to lower costs and/or increase efficacies for using BMP-2. In this study, we describe the development and optimization of a cell-based assay that is sensitive, reproducible, and reliable in identifying reagents that potentiate the effects of BMP-2 in inducing transdifferentiation of C2C12 myoblasts into the osteoblastic phenotype. The assay is based on a BMP-responsive Smad1-driven luciferase reporter gene. LIM mineralization protein-1 (LMP-1) is a novel intracellular LIM domain protein that has been shown by our group to enhance cellular responsiveness to BMP-2. Our previous report elucidated that the binding of LMP-1 with the WW2 domain in Smad ubiquitin regulatory factor-1 (Smurf1) rescues the osteogenic Smads from degradation. Here, using the optimized cell-based assay, we first evaluated the activity of the recombinantly prepared proteins, LMP-1, and its mutant (LMP-1DeltaSmurf1) that lacks the Smurf1-WW2 domain-binding motif. Both the wild type and the mutant proteins were engineered to contain an 11-amino acid HIV-TAT protein derived membrane transduction domain to aid the cellular delivery of recombinant proteins. The cell-based reporter assay confirmed that LMP-1 potentiates the BMP-induced stimulation of C2C12 cells towards the osteoblastic phenotype. The potentiating effect of LMP-1 was significantly reduced when a specific-motif known to interact with Smurf1 was mutated. We validated the results obtained in the reporter assay by also monitoring the expression of mRNA for osteocalcin and alkaline phosphatase (ALP) which is widely accepted osteoblast differentiation marker genes. Finally, we provide further confirmation of our results by measuring the activity of alkaline phosphatase in support of the accuracy and reliability of our cell-based assay. Direct delivery of synthesized protein can be limited by high cost, instability or inadequate post-translational modifications. Thus, there would be a clear benefit for a low cost, cell penetrable chemical compound. We successfully used our gene expression-based assay to choose an active compound from a select group of compounds that were identified by computational screenings as the most likely candidates for mimicking the function of LMP-1. Among them, we selected SVAK-3, a compound that showed a dose-dependent potentiation of BMP-2 activity in inducing osteoblastic differentiation of C2C12 cells. We show that either the full length LMP-1 protein or its potential mimetic compound consistently exhibit similar potentiation of BMP-2 activity even when multiple markers of the osteoblastic phenotype were parallely monitored.
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Synthesis and evaluation of N-[(1S,2S)-3-(4-chlorophenyl)-2-(3-cyanophenyl)-1-methylpropyl]-2-methyl-2-aminopropanamide as human cannabinoid-1 receptor (CB1R) inverse agonists.
Bioorg. Med. Chem. Lett.
PUBLISHED: 05-05-2009
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Obesity is a chronic medical condition that is affecting large population throughout the world. CB1 as a target for treatment of obesity has been under intensive studies. Taranabant was discovered and then developed by Merck as the 1st generation CB1R inverse agonist. Reported here is part of our effort on the 2nd generation of CB1R inverse agonist from the acyclic amide scaffold. We replaced the oxygen linker in taranabant with nitrogen and prepared a series of amino heterocyclic analogs through a divergent synthesis. Although in general, the amine linker gave reduced binding affinity, potent and selective CB1R inverse agonist was identified from the amino heterocycle series. Molecular modeling was applied to study the binding of the amino heterocycle series at CB1 binding site. The in vitro metabolism of representative members was studied and only trace glucuronidation was found. Thus, it suggests that the right hand side of the molecule may not be the appropriate site for glucuronidation.
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Histopathologic risk factors in retinoblastoma in India.
Arch. Pathol. Lab. Med.
PUBLISHED: 04-09-2009
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The presence of histopathologic risk factors is associated with development of metastasis in a patient with retinoblastoma. Adjuvant chemotherapy administered to such patients decreases the risk of metastasis.
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VIPERdb2: an enhanced and web API enabled relational database for structural virology.
Nucleic Acids Res.
PUBLISHED: 03-04-2009
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VIPERdb (http://viperdb.scripps.edu) is a relational database and a web portal for icosahedral virus capsid structures. Our aim is to provide a comprehensive resource specific to the needs of the virology community, with an emphasis on the description and comparison of derived data from structural and computational analyses of the virus capsids. In the current release, VIPERdb(2), we implemented a useful and novel method to represent capsid protein residues in the icosahedral asymmetric unit (IAU) using azimuthal polar orthographic projections, otherwise known as Phi-Psi (Phi-Psi) diagrams. In conjunction with a new Application Programming Interface (API), these diagrams can be used as a dynamic interface to the database to map residues (categorized as surface, interface and core residues) and identify family wide conserved residues including hotspots at the interfaces. Additionally, we enhanced the interactivity with the database by interfacing with web-based tools. In particular, the applications Jmol and STRAP were implemented to visualize and interact with the virus molecular structures and provide sequence-structure alignment capabilities. Together with extended curation practices that maintain data uniformity, a relational database implementation based on a schema for macromolecular structures and the APIs provided will greatly enhance the ability to do structural bioinformatics analysis of virus capsids.
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Invariant polymorphism in virus capsid assembly.
J. Am. Chem. Soc.
PUBLISHED: 02-10-2009
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Directed self-assembly of designed viral capsids holds significant potential for applications in materials science and medicine. However, the complexity of preparing these systems for assembly and the difficulty of quantitative experimental measurements on the assembly process have limited access to critical mechanistic questions that dictate the final product yields and isomorphic forms. Molecular simulations provide a means of elucidating self-assembly of viral proteins into icosahedral capsids and are the focus of the present study. Using geometrically realistic coarse-grained models with specialized molecular dynamics methods, we delineate conditions of temperature and coat protein concentration that lead to the spontaneous self-assembly of T = 1 and T = 3 icosahedral capsids. In addition to the primary product of icosahedral capsids, we observe a ubiquitous presence of nonicosahedral yet highly symmetric and enclosed aberrant capsules in both T = 1 and T = 3 systems. This polymorphism in assembly products recapitulates the scope and morphology of particle types that have been observed in mis-assembly experiments of virus capsids. Moreover, we find that this structural polymorphism in the end point structures is an inherent property of the coat proteins and arises from condition-dependent kinetic mechanisms that are independent of the elemental mechanisms of capsid growth (as long as the building blocks of the coat proteins are all monomeric, dimeric, or trimeric) and the capsid T number. The kinetic mechanisms responsible for self-assembly of icosahedral capsids and aberrant capsules are deciphered; the self-assembly of icosahedral capsids requires a high level of assembly fidelity, whereas self-assembly of nonicosahedral capsules is a consequence of an off-pathway mechanism that is prevalent under nonoptimal conditions of temperature or protein concentration during assembly. The latter case involves kinetically trapped dislocations of pentamer-templated proteins with hexameric organization. These findings provide insights into the complex processes that govern viral capsid assembly and suggest some features of the assembly process that can be exploited to control the assembly of icosahedral capsids and nonicosahedral capsules.
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Modeling and analysis of MH1 domain of Smads and their interaction with promoter DNA sequence motif.
J. Mol. Graph. Model.
PUBLISHED: 01-23-2009
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The Smads are a group of related intracellular proteins critical for transmitting the signals to the nucleus from the transforming growth factor-beta (TGF-beta) superfamily of proteins at the cell surface. The prototypic members of the Smad family, Mad and Sma, were first described in Drosophila and Caenorhabditis elegans, respectively. Related proteins in Xenopus, Humans, Mice and Rats were subsequently identified, and are now known as Smads. Smad protein family members act downstream in the TGF-beta signaling pathway mediating various biological processes, including cell growth, differentiation, matrix production, apoptosis and development. Smads range from about 400-500 amino acids in length and are grouped into the receptor-regulated Smads (R-Smads), the common Smads (Co-Smads) and the inhibitory Smads (I-Smads). There are eight Smads in mammals, Smad1/5/8 (bone morphogenetic protein regulated) and Smad2/3 (TGF-beta/activin regulated) are termed R-Smads, Smad4 is denoted as Co-Smad and Smad6/7 are inhibitory Smads. A typical Smad consists of a conserved N-terminal Mad Homology 1 (MH1) domain and a C-terminal Mad Homology 2 (MH2) domain connected by a proline rich linker. The MH1 domain plays key role in DNA recognition and also facilitates the binding of Smad4 to the phosphorylated C-terminus of R-Smads to form activated complex. The MH2 domain exhibits transcriptional activation properties. In order to understand the structural basis of interaction of various Smads with their target proteins and the promoter DNA, we modeled MH1 domain of the remaining mammalian Smads based on known crystal structures of Smad3-MH1 domain bound to GTCT Smad box DNA sequence (1OZJ). We generated a B-DNA structure using average base-pair parameters of Twist, Tilt, Roll and base Slide angles. We then modeled interaction pose of the MH1 domain of Smad1/5/8 to their corresponding DNA sequence motif GCCG. These models provide the structural basis towards understanding functional similarities and differences among various Smads.
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Comparative proteome analysis of psychrophilic versus mesophilic bacterial species: Insights into the molecular basis of cold adaptation of proteins.
BMC Genomics
PUBLISHED: 01-08-2009
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Cold adapted or psychrophilic organisms grow at low temperatures, where most of other organisms cannot grow. This adaptation requires a vast array of sequence, structural and physiological adjustments. To understand the molecular basis of cold adaptation of proteins, we analyzed proteomes of psychrophilic and mesophilic bacterial species and compared the differences in amino acid composition and substitution patterns to investigate their likely association with growth temperatures.
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Tomato bushy stunt virus (TBSV), a versatile platform for polyvalent display of antigenic epitopes and vaccine design.
Virology
PUBLISHED: 01-07-2009
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Viruses-like particles (VLPs) are frequently being used as platforms for polyvalent display of foreign epitopes of interest on their capsid surface to improve their presentation enhancing the antigenicity and host immune response. In the present study, we used the VLPs of Tomato bushy stunt virus (TBSV), an icosahedral plant virus, as a platform to display 180 copies of 16 amino acid epitopes of ricin toxin fused to the C-terminal end of a modified TBSV capsid protein (NDelta52). Expression of the chimeric recombinant protein in insect cells resulted in spontaneous assembly of VLPs displaying the ricin epitope. Cryo-electron microscopy and image reconstruction of the chimeric VLPs at 22 A resolution revealed the locations and orientation of the ricin epitope exposed on the TBSV capsid surface. Furthermore, injection of chimeric VLPs into mice generated antisera that detected the native ricin toxin. The ease of fusing of short peptides of 15-20 residues and their ability to form two kinds (T=1, T=3) of bio-nanoparticles that result in the display of 60 or 180 copies of less constrained and highly exposed antigenic epitopes makes TBSV an attractive and versatile display platform for vaccine design.
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Orbital plasmablastic lymphoma: a clinico-pathological correlation of a rare disease and review of literature.
Clin Ophthalmol
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Ocular involvement by plasmablastic lymphoma is extremely rare with very few reports in the literature. Its morphological and immunological resemblance to plasma cell myeloma makes it a diagnostic challenge, while its clinical course, which is characterized by recurrence and death, makes therapy a challenge for clinicians. We present three cases of plasmablastic lymphoma, each of which has distinct clinicoradiological features, and we also review the literature on orbital plasmablastic lymphomas.
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Integrin and defensin modulate the mechanical properties of adenovirus.
J. Virol.
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The propensity for capsid disassembly and uncoating of human adenovirus is modulated by interactions with host cell molecules like integrins and alpha defensins. Here, we use atomic force microscopy (AFM) nanoindentation to elucidate, at the single-particle level, the mechanism by which binding of these host molecules affects virus particle elasticity. Our results demonstrate the direct link between integrin or defensin binding and the mechanical properties of the virus. We show that the structure and geometry of adenovirus result in an anisotropic elastic response that relates to icosahedral symmetry. This elastic response changes upon binding host molecules. Whereas integrin binding softens the vertex regions, binding of a human alpha defensin has exactly the opposite effect. Our results reveal that the ability of these host molecules to influence adenovirus disassembly correlates with a direct effect on the elastic strength of the penton region. Host factors that influence adenovirus infectivity thus modulate the elastic properties of the capsid. Our findings reveal a direct link between virus-host interactions and capsid mechanics.
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Persistent complete molecular remission after nilotinib and graft-versus-leukemia effect in an acute lymphoblastic leukemia patient with cytogenetic relapse after allogeneic stem cell transplantation.
Exp Hematol Oncol
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We report the successful treatment and sustained molecular remission using single agent nilotinib in a relapsed Philadelphia chromosome positive (Ph+) acute lymphoblastic leukemia patient after allogeneic hematopoietic stem cell transplantation. Compared to previously published studies, this is the first report where a patient did not receive additional chemotherapy after relapse, nor did she receive donor lymphocyte infusions. With nilotinib, the patient reverted back to normal blood counts and 100% donor reconstitution by single tandem repeat (STR) chimerism analysis in the bone marrow and in peripheral blood, granulocytes, T and B-lymphocytes. This report also highlights the use of nilotinib in combination with extracorporeal photopheresis (ECP) for concomitant graft-versus-host disease. Our data suggests that ECP, together with nilotinib, did not adversely affect the overall Graft-versus-leukemia (GVL) effect.
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Formulation and optimization of mucoadhesive bilayer buccal tablets of atenolol using simplex design method.
Int J Pharm Investig
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In the present study, mucoadhesive buccal bilayer tablets of atenolol were fabricated with the objective of avoiding first pass metabolism and to improve its bioavailability with reduction in dosing frequency. Hence, the aim of this work was to design oral controlled release mucoadhesive tablets of atenolol and to optimize the drug release profile and bioadhesion.
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Derailed estrogen signaling and breast cancer: an authentic couple.
Endocr. Rev.
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Estrogen or 17?-estradiol, a steroid hormone, plays a critical role in the development of mammary gland via acting through specific receptors. In particular, estrogen receptor-? (ER?) acts as a transcription factor and/or a signal transducer while participating in the development of mammary gland and breast cancer. Accumulating evidence suggests that the transcriptional activity of ER? is altered by the action of nuclear receptor coregulators and might be responsible, at least in part, for the development of breast cancer. In addition, this process is driven by various posttranslational modifications of ER?, implicating active participation of the upstream receptor modifying enzymes in breast cancer progression. Emerging studies suggest that the biological outcome of breast cancer cells is also influenced by the cross talk between microRNA and ER? signaling, as well as by breast cancer stem cells. Thus, multiple regulatory controls of ER? render mammary epithelium at risk for transformation upon deregulation of normal homeostasis. Given the importance that ER? signaling has in breast cancer development, here we will highlight how the activity of ER? is controlled by various regulators in a spatial and temporal manner, impacting the progression of the disease. We will also discuss the possible therapeutic value of ER? modulators as alternative drug targets to retard the progression of breast cancer.
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Late effects in hematopoietic cell transplant recipients with acquired severe aplastic anemia: a report from the late effects working committee of the center for international blood and marrow transplant research.
Biol. Blood Marrow Transplant.
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With improvements in hematopoietic cell transplant (HCT) outcomes for severe aplastic anemia (SAA), there is a growing population of SAA survivors after HCT. However, there is a paucity of information regarding late effects that occur after HCT in SAA survivors. This study describes the malignant and nonmalignant late effects in survivors with SAA after HCT. A descriptive analysis was conducted of 1718 patients post-HCT for acquired SAA between 1995 and 2006 reported to the Center for International Blood and Marrow Transplant Research (CIBMTR). The prevalence and cumulative incidence estimates of late effects are reported for 1-year HCT survivors with SAA. Of the HCT recipients, 1176 (68.5%) and 542 (31.5%) patients underwent a matched sibling donor (MSD) or unrelated donor (URD) HCT, respectively. The median age at the time of HCT was 20 years. The median interval from diagnosis to transplantation was 3 months for MSD HCT and 14 months for URD HCT. The median follow-up was 70 months and 67 months for MSD and URD HCT survivors, respectively. Overall survival at 1 year, 2 years, and 5 years for the entire cohort was 76% (95% confidence interval [CI]: 74-78), 73% (95% CI: 71-75), and 70% (95% CI: 68-72). Among 1-year survivors of MSD HCT, 6% had 1 late effect and 1% had multiple late effects. For 1-year survivors of URD HCT, 13% had 1 late effect and 2% had multiple late effects. Among survivors of MSD HCT, the cumulative incidence estimates of developing late effects were all <3% and did not increase over time. In contrast, for recipients of URD HCT, the cumulative incidence of developing several late effects exceeded 3% by 5 years: gonadal dysfunction 10.5% (95% CI: 7.3-14.3), growth disturbance 7.2% (95% CI: 4.4-10.7), avascular necrosis 6.3% (95% CI: 3.6-9.7), hypothyroidism 5.5% (95% CI: 2.8-9.0), and cataracts 5.1% (95% CI: 2.9-8.0). Our results indicated that all patients undergoing HCT for SAA remain at risk for late effects, must be counseled about, and should be monitored for late effects for the remainder of their lives.
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Evaluation of HLA matching in unrelated hematopoietic stem cell transplantation for nonmalignant disorders.
Blood
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The importance of human leukocyte antigen (HLA) matching in unrelated donor transplantation for nonmalignant diseases (NMD) has yet to be defined. We analyzed data from 663 unrelated marrow and peripheral blood stem cell transplants performed from 1995 to 2007 for treatment of NMD. Transplantation from a donor mismatched at the HLA-A, -B, -C, or -DRB1, but not -DQB1 or -DPB1, loci was associated with higher mortality in multivariate analyses (P = .002). The hazard ratio for mortality for single (7/8) and double mismatched (6/8) transplants was 1.29 (0.97-1.72; P = .079) and 1.82 (1.30-2.55; P = .0004), respectively, compared with 8/8 matched transplants. HLA mismatches were not associated with acute or chronic GVHD, but were strongly associated with graft failure. After adjustment for other factors, the odds ratio for graft failure for 7/8 and 6/8 (allele and/or antigen) matched pairs compared with 8/8 matched transplants was 2.81 (1.74-4.54; P < .0001) and 2.22 (1.26-3.97; P = .006), respectively. Patients with NMD should receive transplants from allele matched (8/8) donors if possible. Unlike the case with malignancies, HLA mismatching in NMD is associated with graft failure rather than GVHD.
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Ag44(SR)30(4-): a silver-thiolate superatom complex.
Nanoscale
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Intensely and broadly absorbing nanoparticles (IBANs) of silver protected by arylthiolates were recently synthesized and showed unique optical properties, yet question of their dispersity and their molecular formulas remained. Here IBANs are identified as a superatom complex with a molecular formula of Ag(44)(SR)(30)(4-) and an electron count of 18. This molecular character is shared by IBANs protected by 4-fluorothiophenol or 2-naphthalenethiol. The molecular formula and purity is determined by mass spectrometry and confirmed by sedimentation velocity-analytical ultracentrifugation. The data also give preliminary indications of a unique structure and environment for Ag(44)(SR)(30)(4-).
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Endodontic management of mandibular first molar with middle distal canal: a case report.
Case Rep Dent
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The knowledge of variations in root canal morphology is critical for a successful endodontic treatment. This article presents the endodontic management of a unique case of mandibular molar with middle distal canal which is quite uncommon.
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Evaluation of HER-2/neu status in breast cancer specimens using immunohistochemistry (IHC) & fluorescence in-situ hybridization (FISH) assay.
Indian J. Med. Res.
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Fluorescence in situ hybridization (FISH) is increasingly being recognized as the most accurate and predictive test for HER 2/neu gene amplification and response to therapy in breast cancer. In the present study we investigated HER-2/neu gene amplification by FISH in breast carcinoma tissue specimens and compared the results with that of immunohistochemical (IHC) analysis.
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Ligand dependence of the synthetic approach and chiroptical properties of a magic cluster protected with a bicyclic chiral thiolate.
Chem. Commun. (Camb.)
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Chiral gold clusters stabilised by enantiopure thiolates were prepared, size-selected and characterised by circular dichroism and mass spectrometry. The product distribution is found to be ligand dependent. Au(25) clusters protected with camphorthiol show clear resemblance of their chiroptical properties with their glutathionate analogue.
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Structure of human adenovirus.
Curr Opin Virol
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A detailed structural analysis of the entire human adenovirus capsid has been stymied by the complexity and size of this 150 MDa macromolecular complex. Over the past 10 years, the steady improvements in viral genome manipulation concomitant with advances in crystallographic techniques and data processing software has allowed structure determination of this virus by X-ray diffraction at 3.5 ? resolution. The virus structure revealed the location, folds, and interactions of major and minor (cement proteins) on the inner and outer capsid surface. This new structural information sheds further light on the process of adenovirus capsid assembly and virus-host cell interactions.
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Natural product biosynthetic gene diversity in geographically distinct soil microbiomes.
Appl. Environ. Microbiol.
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The number of bacterial species estimated to exist on Earth has increased dramatically in recent years. This newly recognized species diversity has raised the possibility that bacterial natural product biosynthetic diversity has also been significantly underestimated by previous culture-based studies. Here, we compare 454-pyrosequenced nonribosomal peptide adenylation domain, type I polyketide ketosynthase domain, and type II polyketide ketosynthase alpha gene fragments amplified from cosmid libraries constructed using DNA isolated from three different arid soils. While 16S rRNA gene sequence analysis indicates these cloned metagenomes contain DNA from similar distributions of major bacterial phyla, we found that they contain almost completely distinct collections of secondary metabolite biosynthetic gene sequences. When grouped at 85% identity, only 1.5% of the adenylation domain, 1.2% of the ketosynthase, and 9.3% of the ketosynthase alpha sequence clusters contained sequences from all three metagenomes. Although there is unlikely to be a simple correlation between biosynthetic gene sequence diversity and the diversity of metabolites encoded by the gene clusters in which these genes reside, our analysis further suggests that sequences in one soil metagenome are so distantly related to sequences in another metagenome that they are, in many cases, likely to arise from functionally distinct gene clusters. The marked differences observed among collections of biosynthetic genes found in even ecologically similar environments suggest that prokaryotic natural product biosynthesis diversity is, like bacterial species diversity, potentially much larger than appreciated from culture-based studies.
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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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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.