249 research outputs found
Distribution of Connectin (Titin) and Transverse Tubules at Myotendinous Junctions
The ends of muscle fibers form many longitudinal projections which are further divided into numerous processes and attach to the collagen fibrils of tendons to form myotendinous junctions (MTJs). Immunocytochemical and electron microscopic observations on pectoralis muscles of the chicken revealed the presence of an elastic filamentous protein, connectin (titin), within the terminal sarcomere on the side adjacent to the terminal Z bands, and the absence of connectin and myosin and the presence of actin at the apical sarcoplasmic region of MTJ processes between the terminal Z band and the MTJ sarcolemma. Intermediate voltage electron microscopy showed that T tubules in the terminal sarcomere were absent at the level of the A-I junction on the MTJ side in the rat vastus intermedius, and at the level of the terminal Z band or under the MTJ subsarcolemmal densities in the chicken pectoralis
Effect of Static Extraction TIME on Extraction Efficiencies Using On-line Supercritical Fluid Extraction-High Performance Liquid Chromatography for Lipoquinone Analysis in Activated Sludge
Analysis of microbial community is important for monitoring the performance of biological processes. One of the most simple, quantitative and high reproducible method for analysis of the microbial community is lipoquinone profile method. Lipoquinone is constituent of bacterial plasma membrane that is essential for electron transporter. Lipoquinone could be used as a biomarker to analyze the microbial community because in general one species or genus of bacteria has one dominant type of lipoquinone, thus any changes in the lipoquinone profile would reflect the changes in the microbial community. The method for lipoquinone determination in environmental sample is direct extraction using organic solvent and analysis using chromatography system. Since the method is tedious and uses a large amount of organic solvent, the on-line supercritical fluid extraction-high performance liquid chromatography (on-line SFE-HPLC) has been developed to simplify the method, and was successful determine lipoquinone compounds in activated sludges. The effect of static extraction time on extraction efficiencies of the lipoquinone was investigated in order to eliminate the water pump and methanol pump in the previous system. The CO2 was used as an extraction solvent. The 0.1 g of freeze dried activated sludge was placed into a 1 mL stainless steel extraction vessel and methanol was spiked into the sludge as a modifier. The SFE was connected to HPLC by using trapping column as an interface for collecting lipoquinone extracted from the sludge. The static extraction time was conducted by allowed the matrix to immersed in CO2 and methanol. When the static extraction time finished, the dynamic extraction time was carried out. The extracted and trapped lipoquinone then directly transferred to HPLC system for determination. In this study, the effect of static, dynamic extraction time and volume of spiked methanol were optimized using simplified on-line SFEHPLC for lipoquinone analysis. The best results in terms of extraction yield were obtained at 25 MPa, 45°C, 10 min static extraction time with 500 µL methanol spiked, and 25 min dynamic extraction time with 0.9 mL min-1 CO2 flow rate. It was concluded that the developed method could simplify the online SFE-HPLC system of lipoquinone determination which is useful for a rapid and routine analysis of microbial community in activated sludge
Metallopanstimulin as a marker for head and neck cancer
BACKGROUND: Metallopanstimulin (MPS-1) is a ribosomal protein that is found in elevated amounts in the sera of patients with head and neck squamous cell carcinoma (HNSCC). We used a test, denoted MPS-H, which detects MPS-1 and MPS-1-like proteins, to determine the relationship between MPS-H serum levels and clinical status of patients with, or at risk for, HNSCC. PATIENTS AND METHODS: A total of 125 patients were prospectively enrolled from a university head and neck oncology clinic. Participants included only newly diagnosed HNSCC patients. Two control groups, including 25 non-smokers and 64 smokers, were studied for comparison. A total of 821 serum samples collected over a twenty-four month period were analyzed by the MPS-H radioimmunoassay. RESULTS: HNSCC, non-smokers, and smokers had average MPS-H values of 41.5 ng/mL, 10.2 ng/mL, and 12.8 ng/mL, respectively (p = 0.0001). CONCLUSION: We conclude that MPS-1 and MPS-1-like proteins are elevated in patients with HNSCC, and that MPS-H appears to be a promising marker of presence of disease and response to treatment in HNSCC patients
A proteomic approach for the identification of novel lysine methyltransferase substrates
<p>Abstract</p> <p>Background</p> <p>Signaling via protein lysine methylation has been proposed to play a central role in the regulation of many physiologic and pathologic programs. In contrast to other post-translational modifications such as phosphorylation, proteome-wide approaches to investigate lysine methylation networks do not exist.</p> <p>Results</p> <p>In the current study, we used the ProtoArray<sup>® </sup>platform, containing over 9,500 human proteins, and developed and optimized a system for proteome-wide identification of novel methylation events catalyzed by the protein lysine methyltransferase (PKMT) SETD6. This enzyme had previously been shown to methylate the transcription factor RelA, but it was not known whether SETD6 had other substrates. By using two independent detection approaches, we identified novel candidate substrates for SETD6, and verified that all targets tested <it>in vitro </it>and in cells were genuine substrates.</p> <p>Conclusions</p> <p>We describe a novel proteome-wide methodology for the identification of new PKMT substrates. This technological advance may lead to a better understanding of the enzymatic activity and substrate specificity of the large number (more than 50) PKMTs present in the human proteome, most of which are uncharacterized.</p
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Changes in Hematopoietic Cell Transplantation Practices in Response to COVID-19: A Survey from the Worldwide Network for Blood & Marrow Transplantation.
SARS-CoV-2 has spread rapidly worldwide, but the full impact of the COVID-19 pandemic on the field of hematopoietic cell transplantation (HCT) remains unknown. To understand this better, an 18-item online survey was disseminated by the Worldwide Network for Blood & Marrow Transplantation with questions exploring SARS-CoV-2 testing algorithms, mobilization, and cryopreservation strategies and COVID-19 infections in allogeneic related and autologous hematopoietic progenitor cell (HPC) donors. The aim of this survey was to assess the impact of the outbreak on policies relating to HPC mobilization, collection, and processing with respect to changes in daily routine. A total of 91 individual responses from distinct centers in 6 continents were available for analysis. In these centers, the majority (72%) of allogeneic related and autologous donors are routinely tested for SARS-CoV-2 before HPC collection, and 80% of centers implement cryopreservation of allogeneic HPC grafts before commencing conditioning regimens in patients. Five related and 14 autologous donors who tested positive for COVID-19 did not experience any unexpected adverse events or reactions during growth factor administration (eg, hyperinflammatory syndrome). These data are limited by the small number of survey respondents but nonetheless suggest that centers are following the recommendations of appropriate scientific organizations and provide some preliminary data to suggest areas of further study
Clinical impact of the loss of chromosome 7q on outcomes of patients with myelodysplastic syndromes treated with allogeneic hematopoietic stem cell transplantation
We conducted a nationwide retrospective study to evaluate the prognostic influence of +1, der(1;7)(q10;p10) [hereafter der(1;7)] and ?7/del(7q) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) for de novo myelodysplastic syndromes (MDS). In this database, 69 MDS patients with der(1;7), 75 with ?7/del(7q), and 511 with normal karyotype (NK) underwent allo-HSCT at advanced disease status. The 3-year overall survival (OS) and cumulative incidence of relapse (CIR) were 50.4 and 19.4% for those with der(1;7), 36.2 and 38.4% for ?7/del(7q),and 51.1 and 20.7% for NK, respectively. In the multivariate analysis, the presence of ?7/del(7q) correlated with a significantly shorter OS (HR [95% CI], 1.38 [1.00?1.89]; P = 0.048) and higher CIR (HR, 2.11 [1.36?3.28]; P = 0.001) than those with NK. There were 23 patients with der(1;7), 29 with ?7/del(7q), and 347 with NK who underwent allo-HSCT at early disease status.The 3-year OS and CIR were as follows: 47.3 and 9.5% for the der(1;7) group, 70.5 and 13.8% for ?7/del(7q), and 70.9 and 5.6% for NK,respectively. No significant differences were observed in OS and CIR among three groups. The impact of the loss of chromosome 7q on OS and CIR may differ based on its type and disease status after allo-HSCT for MDS
Analytical in vitro approach for studying cyto- and genotoxic effects of particulate airborne material
In the field of inhalation toxicology, progress in the development of in vitro methods and efficient exposure strategies now offers the implementation of cellular-based systems. These can be used to analyze the hazardous potency of airborne substances like gases, particles, and complex mixtures (combustion products). In addition, the regulatory authorities require the integration of such approaches to reduce or replace animal experiments. Although the animal experiment currently still has to provide the last proof of the toxicological potency and classification of a certain compound, in vitro testing is gaining more and more importance in toxicological considerations. This paper gives a brief characterization of the CULTEX® Radial Flow System exposure device, which allows the exposure of cultivated cells as well as bacteria under reproducible and stable conditions for studying cellular and genotoxic effects after the exposure at the air–liquid or air–agar interface, respectively. A commercial bronchial epithelial cell line (16HBE14o-) as well as Salmonella typhimurium tester strains were exposed to smoke of different research and commercial available cigarettes. A dose-dependent reduction of cell viability was found in the case of 16HBE14o- cells; S. typhimurium responded with a dose-dependent induction of revertants. The promising results recommend the integration of cellular studies in the field of inhalation toxicology and their regulatory acceptance by advancing appropriate validation studies
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