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11.
Amit Kumar Solanki Abhishek Acharya Himani Kaushik Bharti Bhatia Lalit C Garg 《Bioinformation》2021,17(6):628
Beta toxin from Clostridium perfringens after being secreted in gut is capable of causing necrotic enteritis in humans and several other animal species and does not respond to routinely used antibiotics. Therefore, there is a need to design an effective inhibitor for the Clostridium perfringens beta toxin (CPB) using cutting edge drug discovery technologies. Hence, potential CPB inhibitors were identified using computer aided screening of compounds from the ZINC database. Further, we document the molecular docking analysis of Clostridium perfringens beta toxin model (that revealed 4 binding pockets, A-D) with the identified potential inhibitors. We show that ZINC291192 [N-[(1-methylindol-3-yl) methyl eneamino]-7,10-dioxabicyclo[4.4.0]deca-2,4,11-triene-8- carboxamide] has optimal binding features with calculated binding energy of -10.38 kcal/mol and inhibition constant of 24.76 nM for further consideration. 相似文献
12.
Implants of chloroquine phosphate (CQP) using biodegradable polymer, gelatin (G) and cross-linked gelatin (CLG) were prepared and evaluated to assess their physicochemical properties and in vitro release profile. The mechanism and kinetics of release were studied to correlate the release phenomenon with the formulation parameters. Out of many batches of the implants investigated, the implant prepared with 20% gelatin at 2:1 drug polymer ratio, 10% crosslinking agent and 2% plasticizer (Batch J) was found to provide optimum release behavior conforming to the requirements of a long term implant for a week. In vivo studies conducted on albino rats showed consistent therapeutic blood level over a period of 7 days. Mean residence time (MRT) of the drug released in the body, calculated as the ratio of the area under the first moment curve (AUMC) to area under concentration time curve (AUC) was 72 hr for implant against 2.42 hr for subcutaneous injection. 相似文献
13.
Ayse Ercumen Benjamin F. Arnold Emily Kumpel Zachary Burt Isha Ray Kara Nelson John M. Colford Jr. 《PLoS medicine》2015,12(10)
Background
Intermittent delivery of piped water can lead to waterborne illness through contamination in the pipelines or during household storage, use of unsafe water sources during intermittencies, and limited water availability for hygiene. We assessed the association between continuous versus intermittent water supply and waterborne diseases, child mortality, and weight for age in Hubli-Dharwad, India.Methods and Findings
We conducted a matched cohort study with multivariate matching to identify intermittent and continuous supply areas with comparable characteristics in Hubli-Dharwad. We followed 3,922 households in 16 neighborhoods with children <5 y old, with four longitudinal visits over 15 mo (Nov 2010–Feb 2012) to record caregiver-reported health outcomes (diarrhea, highly credible gastrointestinal illness, bloody diarrhea, typhoid fever, cholera, hepatitis, and deaths of children <2 y old) and, at the final visit, to measure weight for age for children <5 y old. We also collected caregiver-reported data on negative control outcomes (cough/cold and scrapes/bruises) to assess potential bias from residual confounding or differential measurement error.Continuous supply had no significant overall association with diarrhea (prevalence ratio [PR] = 0.93, 95% confidence interval [CI]: 0.83–1.04, p = 0.19), bloody diarrhea (PR = 0.78, 95% CI: 0.60–1.01, p = 0.06), or weight-for-age z-scores (Δz = 0.01, 95% CI: −0.07–0.09, p = 0.79) in children <5 y old. In prespecified subgroup analyses by socioeconomic status, children <5 y old in lower-income continuous supply households had 37% lower prevalence of bloody diarrhea (PR = 0.63, 95% CI: 0.46–0.87, p-value for interaction = 0.03) than lower-income intermittent supply households; in higher-income households, there was no significant association between continuous versus intermittent supply and child diarrheal illnesses. Continuous supply areas also had 42% fewer households with ≥1 reported case of typhoid fever (cumulative incidence ratio [CIR] = 0.58, 95% CI: 0.41–0.78, p = 0.001) than intermittent supply areas. There was no significant association with hepatitis, cholera, or mortality of children <2 y old; however, our results were indicative of lower mortality of children <2 y old (CIR = 0.51, 95% CI: 0.22–1.07, p = 0.10) in continuous supply areas. The major limitations of our study were the potential for unmeasured confounding given the observational design and measurement bias from differential reporting of health symptoms given the nonblinded treatment. However, there was no significant difference in the prevalence of the negative control outcomes between study groups that would suggest undetected confounding or measurement bias.Conclusions
Continuous water supply had no significant overall association with diarrheal disease or ponderal growth in children <5 y old in Hubli-Dharwad; this might be due to point-of-use water contamination from continuing household storage and exposure to diarrheagenic pathogens through nonwaterborne routes. Continuous supply was associated with lower prevalence of dysentery in children in low-income households and lower typhoid fever incidence, suggesting that intermittently operated piped water systems are a significant transmission mechanism for Salmonella typhi and dysentery-causing pathogens in this urban population, despite centralized water treatment. Continuous supply was associated with reduced transmission, especially in the poorer higher-risk segments of the population. 相似文献14.
Gulati A Sood S Rahi P Thakur R Chauhan S Chawla I 《Journal of microbiology and biotechnology》2011,21(6):545-555
The diversity elucidation by amplified ribosomal DNA restriction analysis and 16S rDNA sequencing of 96 associative diazotrophs, isolated from the feeder roots of tea on enriched nitrogen-free semisolid media, revealed the predominance of Gram-positive over Gram-negative bacteria within the Kangra valley in Himachal Pradesh, India. The Gram-positive bacteria observed belong to two taxonomic groupings; Firmicutes, including the genera Bacillus and Paenibacillus; and Actinobacteria, represented by the genus Microbacterium. The Gram-negative bacteria included alpha-Proteobacteria genera Brevundimonas, Rhizobium, and Mesorhizobium; gamma-Proteobacteria genera Pseudomonas and Stenotrophomonas; and beta-Proteobacteria genera Azospira, Burkholderia, Delftia, Herbaspirillum and Ralstonia. The low level of similarity of two isolates, with the type strains Paenibacillus xinjiangensis and Mesorhizobium albiziae, suggests the possibility of raising species novum. The bacterial strains of different phylogenetic groups exhibited distinct carbon-source utilization patterns and fatty acid methyl ester profiles. The strains differed in their nitrogenase activities with relatively high activity seen in the Gramnegative strains exhibiting the highest similarity to Azospira oryzae, Delftia lacustris and Herbaspirillum huttiense. 相似文献
15.
Srivastava BK Soni R Patel JZ Solanki M Valani D Gupta S Mishra B Takale V Pandya P Jain MR Patel PR 《Bioorganic & medicinal chemistry letters》2007,17(18):5227-5232
Design and synthesis of a few novel methylamino piperidinyl substituted oxazolidinones are reported. Their antibacterial activities have been evaluated in a MIC assay against broader panel of both susceptible and resistant Gram-positive strains. (S)-N-{3-[3-Fluoro-4-(methyl-{1-[3-(5-nitrofuran-2-yl)-acryloyl]-piperidin-4-yl}-amino)-phenyl]-2-oxo-oxazolidin-5-ylmethyl}-acetamide 4i has shown comparable antibacterial activity to linezolid and eperezolid in the MIC assay, additionally compound 4i showed good antibacterial activity with an in vitro MIC value of 2-4 microg/mL against linezolid resistant Staphylococcus aureus (linezolid 16 microg/mL). 相似文献
16.
Zhixiang Tong Aniruddh Solanki Allison Hamilos Oren Levy Kendall Wen Xiaolei Yin Jeffrey M Karp 《The EMBO journal》2015,34(8):987-1008
Derived from any somatic cell type and possessing unlimited self-renewal and differentiation potential, induced pluripotent stem cells (iPSCs) are poised to revolutionize stem cell biology and regenerative medicine research, bringing unprecedented opportunities for treating debilitating human diseases. To overcome the limitations associated with safety, efficiency, and scalability of traditional iPSC derivation, expansion, and differentiation protocols, biomaterials have recently been considered. Beyond addressing these limitations, the integration of biomaterials with existing iPSC culture platforms could offer additional opportunities to better probe the biology and control the behavior of iPSCs or their progeny in vitro and in vivo. Herein, we discuss the impact of biomaterials on the iPSC field, from derivation to tissue regeneration and modeling. Although still exploratory, we envision the emerging combination of biomaterials and iPSCs will be critical in the successful application of iPSCs and their progeny for research and clinical translation. 相似文献
17.
Yumi Ueki Michael A Hadders Melanie B Weisser Isha Nasa Paula SoteloParrilla Lauren E Cressey Tanmay Gupta Emil P T Hertz Thomas Kruse Guillermo Montoya A Arockia Jeyaprakash Arminja Kettenbach Susanne M A Lens Jakob Nilsson 《EMBO reports》2021,22(7)
The shugoshin proteins are universal protectors of centromeric cohesin during mitosis and meiosis. The binding of human hSgo1 to the PP2A‐B56 phosphatase through a coiled‐coil (CC) region mediates cohesion protection during mitosis. Here we undertook a structure function analysis of the PP2A‐B56‐hSgo1 complex, revealing unanticipated aspects of complex formation and function. We establish that a highly conserved pocket on the B56 regulatory subunit is required for hSgo1 binding and cohesion protection during mitosis in human somatic cells. Consistent with this, we show that hSgo1 blocks the binding of PP2A‐B56 substrates containing a canonical B56 binding motif. We find that PP2A‐B56 bound to hSgo1 dephosphorylates Cdk1 sites on hSgo1 itself to modulate cohesin interactions. Collectively our work provides important insight into cohesion protection during mitosis. 相似文献
18.
Acylation of Pseudomonas cepacia lipase with Pyromellitic dianhydride to modify 72% of total amino groups was carried out. Different organic solvents were screened for precipitation of modified lipase. It was found that 1,2-dimethoxyethane was the best precipitant which precipitated 97% protein and complete activity. PCMC (protein coated microcrystals), CLPCMC (crosslinked protein coated microcrystals), EPROS (enzyme precipitated and rinsed with organic solvents) and pH tuned preparations of modified and unmodified lipase were prepared and used for carrying out transesterification reaction with n-octane and dimethyl formamide (DMF) as reaction medium. In n-octane, among all the preparations, CLPCMC of modified lipase gave highest rate (1970 nmol min−1 mg−1) as compared to unmodified pH tuned lipase (128 nmol min−1 mg−1). In DMF, with both 1% (v/v) and 5% (v/v) water content, CLPCMC showed highest initial rate of 0.72 and 7.2 nmol min−1 mg−1, respectively. Unmodified pH tuned lipase showed no activity at all in DMF with both 1% and 5% (v/v) water content. 相似文献
19.
20.
A birth during the day by a capped langur (Trachypithecus pileatus Blyth, 1843) was recorded at Pakhui Wildlife Sanctuary, Arunachal Pradesh, India. The birth took 43 min. Allomothering was observed 3 h after the birth. An average of 9% of daily active time was shared by four allomothers (three adults, one subadult) during the first 15 days of the infants life. Total time allomothering was proportional to the age of the allomothers (241 min for oldest; 214 min for youngest). 相似文献