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991.
Study of antibiotic resistance was done among the metal tolerant E. coli isolates from hospital wastewater at Lucknow city. Metal
tolerance was determined in terms of visible growth on metal amended plates at their varying concentrations. MICs were also
determined among all metal tolerant E. coli isolates. All the isolates showed their MIC in between 100-2000 µg/ml while maximum
isolates demonstrated their MICs at 400, 800 and 1600 µg/ml against all the metal tested. 23.07% of the isolates showed their MIC at
2000 µg/ml against Ni3+. Multiple antibiotic resistances were recorded among all the metal resistant E.coli isolates. A high level of
resistance was observed against Methicillin (86.53%) followed by penicillin (73.07%), Cephradin (57.69%), Rifampicin (34.61%),
Erythromycin (26.92%), Nalidixic acids (25%), Chloramphenicol (3.84%) and least to Gentamycine (1.92%). Streptomycin was
recorded most effective against E.coli isolates among the entire antibiotic tested. Antimicrobial resistance observed among the
bacteria from the aquatic system contaminated with hospital wastes may be threatful for the environment and public health both. 相似文献
992.
Yee Wen Choon Mohd Saberi Mohamad Safaai Deris Rosli Md. Illias Chuii Khim Chong Lian En Chai Sigeru Omatu Juan Manuel Corchado 《PloS one》2014,9(7)
Microbial strains optimization for the overproduction of desired phenotype has been a popular topic in recent years. The strains can be optimized through several techniques in the field of genetic engineering. Gene knockout is a genetic engineering technique that can engineer the metabolism of microbial cells with the objective to obtain desirable phenotypes. However, the complexities of the metabolic networks have made the process to identify the effects of genetic modification on the desirable phenotypes challenging. Furthermore, a vast number of reactions in cellular metabolism often lead to the combinatorial problem in obtaining optimal gene deletion strategy. Basically, the size of a genome-scale metabolic model is usually large. As the size of the problem increases, the computation time increases exponentially. In this paper, we propose Differential Bees Flux Balance Analysis (DBFBA) with OptKnock to identify optimal gene knockout strategies for maximizing the production yield of desired phenotypes while sustaining the growth rate. This proposed method functions by improving the performance of a hybrid of Bees Algorithm and Flux Balance Analysis (BAFBA) by hybridizing Differential Evolution (DE) algorithm into neighborhood searching strategy of BAFBA. In addition, DBFBA is integrated with OptKnock to validate the results for improving the reliability the work. Through several experiments conducted on Escherichia coli, Bacillus subtilis, and Clostridium thermocellum as the model organisms, DBFBA has shown a better performance in terms of computational time, stability, growth rate, and production yield of desired phenotypes compared to the methods used in previous works. 相似文献
993.
Mohd Basyaruddin Abdul Rahman Muhammad Alif Mohammad Latif Mahiran Basri Abu Bakar Salleh Raja Noor Zaliha Abdul Rahman 《Molecular simulation》2013,39(5):403-407
Problems with transdermal drug delivery were directly associated with the skin barrier which is the lipid bilayer at the stratum corneum. Chemical penetration enhancers such as swollen micelles that formed from the solubilisation of the surfactants in the nano-emulsion system could provide an effective solution. However, the structural properties of swollen micelles from nano-emulsions of palm-oil esters, whose behaviour is related to colloidal systems, have not been studied in great detail. In this paper, we report on the use of molecular dynamics (MD) simulations to investigate the structural properties of swollen micelles of oleyl oleate (OE). Five series of 10 ns MD simulations were performed at different micelle compositions to determine the structural evolution of OE/Span20 (S20) swollen micelles. We also carried out four MD simulations on the structure of S20, OE/S20, Tween80 (T80) and OE/T80 micelles to study the effect of different surfactants and the addition of OE into the systems. The shapes of the swollen micelles were observed to vary by the difference in the micelle composition, the surfactants used and the addition of OE. The results were correlated with published theory, and consistent with experimental results on the phase behaviour of the nano-emulsion system. 相似文献
994.
The activation of nuclear factor kappa B (NF-κB) plays a major role in the pathogenesis of a number of inflammatory diseases. In this study, we investigated the anti-inflammatory mechanism of Gelam honey in inflammation induced rats via NF-κB signalling pathway. Rats paw edema was induced by subplantar injection of 1% carrageenan into the right hind paw. Rats were pre-treated with Gelam honey at different doses (1 or 2 g/kg, p.o.) and NSAID Indomethacin (10 mg/kg, p.o.), in two time points (1 and 7 days). Our results showed that Gelam honey at both concentrations suppressed the gene expressions of NF-κB (p65 & p50) and IκBα in inflamed rats paw tissues. In addition, Gelam honey inhibited the nuclear translocation and activation of NF-κB and decreased the cytosolic degradation of IκBα dose dependently in inflamed rats paw tissues. The immunohistochemical expressions of pro-inflammatory mediators COX-2 and TNF-α were also decreased in inflamed rats paw tissues when treated with Gelam honey. The results of our findings suggest that Gelam honey exhibits its inhibitory effects by attenuating NF-κB translocation to the nucleus and inhibiting IκBα degradation, with subsequent decrease of inflammatory mediators COX-2 and TNF-α. 相似文献
995.
Salma Firdaus Nazia Hassan Mohd. Aamir Mirza Tabasum Ara Hamed A. El-Serehy Fahad A. Al-Misned Zeenat Iqbal 《Saudi Journal of Biological Sciences》2021,28(1):317-326
Candidal vulvovaginitis (CVV), is the second most leading vaginal infection (global prevalence > 75%), caused due to excessive growth of Candida spp., predominantly Candida albicans (>95% cases). The current treatment regimens for CVV are marred with the challenges of fungal resistance & infection recurrence, subsequently leading to the compromised therapeutic efficacy of anti-fungal drugs, prolonged treatment and low patient compliance. The core of the present research was the fabrication & investigation of 2 T-SLN (solid lipid nanoparticles) gel carrying luliconazole for the amelioration of CVV. ‘2T’ symbolizes transvaginal & thermosensitive attributes of the present formulation. SLNs were prepared by a modified melt emulsification-ultra sonication method using a combination of solid lipids (Gelucire 50/13 & Precirol ATO 5), surfactant (Tween 80) and co-surfactant (Kolliphor). Formulation by design (FbD) approach was adopted to obtain appropriately screened and tailored SLNs. The optimized SLNs yielded a particle size, polydispersity index & entrapment efficiency of 62.18 nm, 0.263 & 81.5% respectively. To formulate the 2 T-gel, the final SLNs were loaded into Carbopol 971P-NF and Triethanolamine based gel. The 2 T-SLN gel was found to be easily spreadable and homogenous with mean extrudability (15 ± 0.4 g/cm2), viscosity (696.42 ± 2.34 Pa·s) and %drug content (93.24 ± 0.73%) values.. The pH of the prepared 2 T-SLN gel (4.5 ± 0.5) was in concordance with the vaginal pH (normal conditions). For in-vitro characterization of an optimized 2 T-SLN gel the release kinetics & anticandidal activity were assessed which offers a %cumulative drug release of 62 ± 0.5% in 72 h and 37.3 ± 1.5 mm zone of inhibition in 48 h. The visual appearance & dimensions were determined using fluorescent microscopy (spherical shape) & transmission electron microscopy (90–120 nm) respectively. The optimized 2 T-SLN gel showcases a skin-friendly profile with no significant signs of erythema and oedema and was found to be stable at room temperature for 2 months without any visual non-uniformity/cracking/breaking. In conclusion, the current research serves a new therapeutic perspective in assessing the activity of luliconazole for vaginal drug delivery using a 2 T-SLN gel system. 相似文献
996.
Asgher Mohd Per Tasir S. Verma Susheel Pandith Shahzad A. Masood Asim Khan Nafees A. 《Journal of Plant Growth Regulation》2018,37(4):1300-1317
Journal of Plant Growth Regulation - The effect of chromium (Cr) toxicity on four cultivars of mustard (Brassica juncea), Varuna, Pusa Bold, Rohini and SS2, was studied to select the cultivar with... 相似文献
997.
We investigated the structure and Brownian rotational motion of the PEST region (201-268) from human c-Myc oncoprotein, whose overexpression/dysregulation is associated with various types of cancer. The 77-residue PEST fragment revealed a large Stokes radius (~3.1 nm) and CD spectrum highlighting abundance of disordered structure. Changes in structure/dynamics at two specific sites in PEST degron were observed using time-resolved fluorescence spectroscopy by labeling Cys9 near N-terminal with dansyl probe and inserting a Trp70 near C-terminal (PEST M1). Trp in PEST M1 at pH 3 was inaccessible to quencher, showed hindered segmental motion and slow global rotation (~30 ns) in contrast to N-terminal where the dansyl probe was free, exposed with fast global rotation (~5 ns). Remarkably, this large monomeric structure at acidic pH was retained irrespective of ionic strength (0.03-0.25 M) and partially so in presence of 6 M Gdn.HCl. With gradual increase in pH, a structural transition (~pH 4.8) into a more exposed and freely rotating Trp was noticeable. Interestingly, the induced structure at C-terminal also influenced the dynamics of dansyl probe near N-terminal, which otherwise remained unstructured at pH > 5. FRET measurements confirmed a 11 Å decrease in distance between dansyl and indole at pH 4 compared to pH 9, coinciding with enhanced ANS binding and increase in strand/helix population in both PEST fragments. The protonation of glutamate/aspartate residues in C-terminal region of PEST is implicated in this disorder-order transition. This may have a bearing on the role of PEST in endocytic trafficking of eukaryotic proteins. 相似文献
998.
999.
Sunil Kumar Theboral Jeevaraj Mohd H. Yunus Subhra Chakraborty Niranjan Chakraborty 《Plant, cell & environment》2023,46(1):5-22
Stress resilience behaviours in plants are defensive mechanisms that develop under adverse environmental conditions to promote growth, development and yield. Over the past decades, improving stress resilience, especially in crop species, has been a focus of intense research for global food security and economic growth. Plants have evolved specific mechanisms to sense external stress and transmit information to the cell interior and generate appropriate responses. Plant cytoskeleton, comprising microtubules and actin filaments, takes a center stage in stress-induced signalling pathways, either as a direct target or as a signal transducer. In the past few years, it has become apparent that the function of the plant cytoskeleton and other associated proteins are not merely limited to elementary processes of cell growth and proliferation, but they also function in stress response and resilience. This review summarizes recent advances in the role of plant cytoskeleton and associated proteins in abiotic stress management. We provide a thorough overview of the mechanisms that plant cells employ to withstand different abiotic stimuli such as hypersalinity, dehydration, high temperature and cold, among others. We also discuss the crucial role of the plant cytoskeleton in organellar positioning under the influence of high light intensity. 相似文献
1000.
Zinc complexes were reported to have anti-ulcer activity and used as drug for the treatment of gastrointestinal disorders. A novel compound dichlorido-zinc(II)-4-(2-(5-methoxybenzylidene amino)ethyl)piperazin-1-iumphenolate (ZnHMS) was synthesized, characterized and evaluated for its gastroprotective activity against ethanol-induced ulcer in rats. Gross and microscopic lesions, histochemical staining of glycogen storage, biochemical and immunological parameters were taken into consideration. Oral administration of ZnHMS (30 and 60 mg/kg; 14 days) dose-dependently inhibited gastric lesions. It significantly increased the mucus content and total acidity compared to the control group (P<0.01). Serum levels of aspartate (AST), alanine (ALT) transaminases, pro-inflammatory interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) and anti-inflammatory interleukin-10 (IL-10) in the rats exposed to ethanol induced ulceration have been altered. ZnHMS considerably enhances (P<0.05) the protection of gastric epithelia by modulating the acute alterations of AST, ALT, IL-6, IL-10, TNF-α and stomach glycogen. Interestingly, ZnHMS did interfere with the natural release of nitric oxide. In addition, acute toxicity study revealed no abnormal sign to the rats treated with ZnHMS (2000 mg/kg). These findings suggest that the gastroprotective activity of ZnHMS might contribute in adjusting the inflammatory cytokine-mediated oxidative damage to the gastric mucosa. 相似文献