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11.
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Intracellular total soluble proteins of Beauveria bassiana are believed to play an important role in virulence against insect hosts. Thirty B. bassiana isolates collected from different geographical regions and host ranges were characterised by total soluble proteins present in cells, using the SDS–PAGE technique to differentiate the isolates based on virulence and host insect origin. In vitro analysis of total soluble protein profiles of 30 isolates was studied to understand the relationship of isolates with their host of origin and virulence against Helicoverpa armigera. There was a positive relationship between virulence and host origin. All the non-virulent isolates are grouped together. Similarly, highly virulent isolates against H. armigera were grouped together. The relationship between total soluble proteins and pathogenicity was positively correlated. Thirty isolates shared only 22% similarity in their protein profiles.  相似文献   
13.

Objectives

To investigate the associations of environmental MS risk factors with clinical and MRI measures of progression in high-risk clinically isolated syndromes (CIS) after the first demyelinating event.

Methods

We analyzed 211 CIS patients (age: 28.9±7.8 years) enrolled in the SET study, a multi-center study of high-risk CIS patients. Pre-treatment samples were analyzed for IgG antibodies against cytomegalovirus (anti-CMV), Epstein Barr virus (EBV) early nuclear antigen-1 (EBNA-1), viral capsid antigen (VCA), early antigen-diffuse (EA-D), 25 hydroxy-vitamin D3 and cotinine levels and HLA DRB1*1501 status. The inclusion criteria required evaluation within 4 months of the initial demyelinating event, 2 or more brain MRI lesions and the presence of two or more oligoclonal bands in cerebrospinal fluid. All patients were treated with interferon-beta. Clinical and MRI assessments were obtained at baseline, 6, 12, and 24 months.

Results

The time to first relapse decreased and the number of relapses increased with anti-CMV IgG positivity. Smoking was associated with increased number and volume of contrast-enhancing lesions (CEL) during the 2-year period. The cumulative number of CEL and T2 lesions during the 2-year period was greater for individuals in the highest quartile of anti-EBV VCA IgG antibodies. The percent loss of brain volume was increased for those in the highest quartile of with anti-EBV VCA IgG antibodies.

Conclusions

Relapses in CIS patients were associated with CMV positivity whereas anti-EBV VCA positivity was associated with progression on MRI measures, including accumulation of CEL and T2 lesions and development of brain atrophy.  相似文献   
14.

In India, genetically modified organisms and products thereof are regulated under the “Rules for the manufacture, use, import, export and storage of hazardous microorganisms, genetically engineered organisms or cells, 1989” (referred to as Rules, 1989) notified under the Environment (Protection) Act, 1986. These Rules are implemented by the Ministry of Environment, Forest and Climate Change, Department of Biotechnology and State Governments though six competent authorities. The Rules, 1989 are supported by series of guidelines on contained research, biologics, confined field trials, food safety assessment, environmental risk assessment etc. The definition of genetic engineering in the Rules, 1989 implies that new genome engineering technologies including gene editing technologies like CRISPR/Cas9 and gene drives may be covered under the rules. The regulatory authorities if required, may also review the experiences of other countries in dealing with such new and emerging technologies.

  相似文献   
15.
In Caenorhabditis elegans, the kinase ZYG-1 is required for centrosome duplication. To identify factors that interact with ZYG-1, we used a classical genetic approach and identified 21 szy (suppressor of zyg-1) genes that when mutated restore partial viability to a zyg-1 mutant. None of the suppressors render animals completely independent of zyg-1 activity and analysis of a subset of the suppressors indicates that all restore the normal process of centrosome duplication to zyg-1 mutants. Thirteen of these suppressor mutations confer phenotypes of their own and cytological examination reveals that these genes function in a variety of cellular processes including cell cycle timing, microtubule organization, cytokinesis, chromosome segregation, and centrosome morphology. Interestingly, several of the szy genes play a role in attaching the centrosome to the nuclear envelope. We have found that one such szy gene is sun-1, a gene encoding a nuclear envelope component. We further show that the role of SUN-1 in centrosome duplication is distinct from its role in attachment. Our approach has thus identified numerous candidate regulators of centrosome duplication and uncovered an unanticipated regulatory mechanism involving factors that tether the centrosome to the nucleus.  相似文献   
16.
17.
Isl1(+) cardiovascular progenitors and their downstream progeny play a pivotal role in cardiogenesis and lineage diversification of the heart. The mechanisms that control their renewal and differentiation are largely unknown. Herein, we show that the Wnt/beta-catenin pathway is a major component by which cardiac mesenchymal cells modulate the prespecification, renewal, and differentiation of isl1(+) cardiovascular progenitors. This microenvironment can be reconstituted by a Wnt3a-secreting feeder layer with ES cell-derived, embryonic, and postnatal isl1(+) cardiovascular progenitors. In vivo activation of beta-catenin signaling in isl1(+) progenitors of the secondary heart field leads to their massive accumulation, inhibition of differentiation, and outflow tract (OFT) morphogenic defects. In addition, the mitosis rate in OFT myocytes is significantly reduced following beta-catenin deletion in isl1(+) precursors. Agents that manipulate Wnt signals can markedly expand isl1(+) progenitors from human neonatal hearts, a key advance toward the cloning of human isl1(+) heart progenitors.  相似文献   
18.
SUMMARY:: Suprahepatic inferior vena caval (IVC) injuries are rare but carry nearly a 100% mortality rate. The main problem with its surgical management is the technical difficulty in draining the IVC during cardiopulmonary bypass. In this report, an efficient method of IVC drainage for repair of the IVC on cardiopulmonary bypass is described.  相似文献   
19.
During their commitment and differentiation toward the osteoblast lineage, mesenchymal stem cells secrete a unique extracellular matrix (ECM) that contains large quantities of glycosaminoglycans (GAGs). Proteoglycans (PGs) are major structural and functional components of the ECM and are composed of a core protein to which one or more glycosaminoglycan sugar chains (GAGs) attach. The association of BMP2, a member of the TGF-β super-family of growth factors, and a known heparin-binding protein, with GAGs has been implicated as playing a significant role in modulating the growth factor’s in vitro bioactivity. Here we have characterised an osteoblast-derived matrix (MX) obtained from decellularised MC3T3-E1 cell monolayers for its structural attributes, using SEM and histology, and for its functional ability to maintain cell growth and viability. Using a combination of histology and anion exchange chromatography, we first confirmed the retention of GAGs within MX following the decellularisation process. Then the binding specificity of the retained GAG species within the MX for BMP2 was examined using a BMP2-HBP/EGFP (BMP2 Heparin-Binding Peptide/Enhanced Green Fluorescent Protein) fusion protein. The results of this study provide further evidence for a central role of the ECM in the regulation of BMP2 bioactivity, hence on mesenchymal stem cell commitment to the osteoblast lineage.  相似文献   
20.
In vivo models of myocardial infarction induced by coronary artery ligation (CAL) in rats usually suffer from high early mortality and a low rate of induction. This study investigated the time course initiation of chronic myocardial infarction (CMI) in albino rats and the possibility of reducing early mortality rate due to myocardial infarction by modification of the surgical technique. CAL was carried out by passing the suture through the epicardial layer around the midway of the left anterior descending coronary artery including a small area of the myocardium to avoid mechanical damage to the heart geometry. In addition, the role of endothelin-1 (ET-1) in rat heart with congestive heart failure was critically assessed. Time course initiation experiments were designed by sacrificing the animals at different time intervals and by carrying out physiological, biochemical, histopathological, electron microscopical and immunohistochemical studies. Specific markers of myocardial injury, viz. cardiac troponin-T (cTnT), high sensitivity C-reactive protein, lactate dehydrogenase and fibrinogen were measured at different time points. Serum marker enzymes and activities of lysosomal hydrolases were found to be elevated on the eighth day post-ligation. Histopathological studies demonstrated focal areas showing fibrovascular tissue containing fibroblasts, collagenous ground substance and numerous small capillaries replacing cardiac muscle fibers. Transmission electron micrographs exhibited mitochondrial changes of well-developed irreversible cardiac injury, viz. swelling, disorganization of cristae, appearance of mitochondrial amorphous matrix densities, significant distortion of muscle fibers and distinct disruption of the intercalated discs. Immunoblotting studies confirmed the presence of alpha 2-macroglobulin which supported the inflammatory response. The severity of the CMI was inferred by the measurement of the level of ET-1 in plasma and left ventricle which was significantly higher in the CMI rats than in the sham-operated rats. Immunohistochemical studies at different time intervals showed that there was a significant immunoexpression of ET-1 on the eighth day post-ligation. This study conclusively showed that ligation of left anterior descending artery minimized mortality and ET-1 was expressed during CMI.  相似文献   
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