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81.
Dixit Sharma Ankita Sharma Shailender Kumar Verma Birbal Singh 《Journal of molecular recognition : JMR》2019,32(4)
Orientia tsutsugamushi (Ott) is a causative agent of chigger‐borne zoonosis, scrub typhus which is life threatening and highly pervasive illness in humans. In this report, we have mined and classified the proteins involved in pathways unique to Ott by using high‐throughput computational techniques. The 12 metabolic pathways were found to be unique to the pathogen. Forty‐six proteins were reported to be essential for the pathogen's survival and non‐homologous to the humans. The proteins were categorized into different classes, ie, enzymes, transporters, DNA‐binding, secretory, and outer membrane proteins. Further, in silico analysis of 46 proteins showed that 25 proteins were suitable therapeutic targets with known druggable properties. The structural modeling of B3CSG3 (MurA) protein was carried out and catalytic site essential for its functioning was analyzed. Virtual screening of chemical compounds was performed against modeled structure. The docking study by AutodockVina reported compound from PubChem with CID: 16036947 as best and potential inhibitor by means of docking score and binding affinity. The reliability and stability of the MurA‐16036947 complex were confirmed with molecular dynamics simulation. The report will provide insight to understand the mechanism of pathogenesis of Ott and instigate the development of effective treatment strategies against this disease. 相似文献
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Scaffolds of agar and gelatin were developed using a novel entrapment method where agar and gelatin molecules mutually entrapped one another forming stable cell adhesive matrices. Glutaraldehyde was used as a crosslinking agent for gelatin. Three types of hybrid matrices were prepared using agar and gelatin in different proportions in the weight ratio of 1:1, 2:1, and 3:1. Surface characterization of dry scaffolds was carried out by scanning electron microscope. Swelling studies were carried out in phosphate buffer saline (PBS) at physiological pH 7.4. The integral stability of the scaffolds was evaluated by estimating the released disintegrated gelatin from them in PBS at pH 7.4. The attachment kinetics of the cells was evaluated by culturing mouse fibroblast cell line NIH 3T3 on films. The cytocompatibility of these matrices was determined by studying growth kinetics of NIH 3T3 cells on them and morphology of cells was observed through optical photographs taken at various days of culture. It was found that the matrices containing agar and gelatin in 2:1 weight ratio exhibited best growth kinetics. The results obtained from these studies have suggested that the above-described method is a cheap and easy way to fabricate agar-gelatin hybrid scaffolds to grow cells which can be used in various in vitro tissue engineering applications like screening of drugs. 相似文献
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Members of the herpesviridae family including Kaposi's sarcoma-associated herpesvirus (KSHV) persist latently in their hosts and harbor their genomes as closed circular episomes. Propagation of the KSHV genome into new daughter cells requires replication of the episome once every cell division and is considered critically dependent on expression of the virus encoded latency-associated nuclear antigen (LANA). This study demonstrates a LANA-independent mechanism of KSHV latent DNA replication. A cis-acting DNA element within a discreet KSHV genomic region termed the long unique region (LUR) can initiate and support replication of plasmids lacking LANA-binding sequences or a eukaryotic replication origin. The human cellular replication machinery proteins ORC2 and MCM3 associated with the LUR element and depletion of cellular ORC2 abolished replication of the plasmids indicating that recruitment of the host cellular replication machinery is important for LUR-dependent replication. Thus, KSHV can initiate replication of its genome independent of any trans-acting viral factors. 相似文献
86.
Jaiswal Nancy Verma Yashodhara Misra Pragati 《In vitro cellular & developmental biology. Plant》2022,58(3):427-436
In Vitro Cellular & Developmental Biology - Plant - Licorice (Glycyrrhiza glabra L.), Fabaceae, has a wide range of medicinal properties due to the metabolites found in the plant tissues.... 相似文献
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We have explored the mechanism of coupling of an approximately 50 mT static magnetic field with the α helices of poly-L-lysine. Structural changes in poly-L-lysine were determined by Raman spectroscopy. Our testable hypothesis is that static magnetic fields of this magnitude can couple with the α-helical segments of the polypeptide, and, as a result, the structure of the polypeptide is significantly altered. Our model further suggests that a static magnetic field can promote protein unfolding and can prevent refolding. © 1996 Wiley-Liss, Inc. 相似文献
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Background. A large proportion of patients in primary care are still being maintained on long‐term acid suppression, without any attempts to identify Helicobacter pylori status and to treat those that test positive. Objectives. To assess the prevalence and economic and symptomatic benefits of H. pylori eradication in patients maintained on long‐term H2 receptor antagonists (H2RA) in primary care. Patients and Methods. Patients on long‐term (i.e. 6 months or longer) H2RA were identified from the computerised records of six practices in north England. Helicobacter pylori status was identified using serology and H. pylori positive patients were then offered standard 7‐day proton pump based triple therapy, followed by a urea breath test (UBT) to confirm H. pylori eradication. Those who had a positive UBT were offered a second line course of H. pylori eradication therapy. Follow up period was 1 year. The main outcome measures were improvement in dyspepsia symptom scores, amount of H2RA being consumed, and economic benefits after H. pylori eradication. Results. One thousand and seven patients (1.5%) were identified on long‐term H2RA, of whom 471 (46%) ultimately had their H. pylori serology assessed. Sixty‐three (297) percent of the patients tested had a positive serology for H. pylori, the majority of whom (58%, 172) had prior evidence of peptic ulcer disease. The mean duration of therapy and mean time since endoscopy/barium studies was significantly longer in patients with peptic ulcer disease compared to their counterparts with nonulcer dyspepsia and gastro‐oesophageal reflux disease, p= .0002 and .0001, respectively. After successful H. pylori eradication (which was possible in 84% of the patients), at the end of the 1‐year study period, on an intention to treat basis 62% of the patients could either stop or significantly reduce dosage of their H2RA. There was also significant reduction in the mean dose of H2RA being consumed and severity of symptoms at the end of the study period (p < .00001). Conclusion. Almost two‐thirds of patients on long‐term H2RA in primary care will have a positive serology for H. pylori; the majority of these will have peptic ulcer disease. In over 60% of cases H. pylori eradication led to significant improvement in symptom scores and reduction in dosage of H2RA being consumed. Cessation or reduction in long‐term H2RA prescribing is cost effective. 相似文献
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