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71.
A. K. J. Hasan N. Choudhury A. Begum N. Nahar 《World journal of microbiology & biotechnology》1993,9(1):73-76
Two locally-produced seasonal vegetables, carrot and patol, were preserved in brine, with and without radiation, with marked changes in their properties as foods and their microbiology. The treated vegetables could be preserved, at optimum salt and irradiation levels, for up to 60 days without becoming unacceptable in terms of appearance, texture, flavour and taste. The optimum salt concentrations for preservation of carrot and patol were 2% (w/v) and 3% (w/v), respectively. The microbial load initially showed an upward trend and then declined after 5 to 10 days of storage. Lactic acid bacteria predominated in treated vegetables. 相似文献
72.
Adnan Ali Khan Choudhury James V. Conlan Vanessa Nadine Racloz Simon Andrew Reid Stuart D. Blacksell Stanley G. Fenwick Andrew R. C. Thompson Boualam Khamlome Khamphouth Vongxay Maxine Whittaker 《EcoHealth》2013,10(1):54-62
The parasitic zoonoses human cysticercosis (Taenia solium), taeniasis (other Taenia species) and trichinellosis (Trichinella species) are endemic in the Lao People’s Democratic Republic (Lao PDR). This study was designed to quantify the economic burden pig-associated zoonotic disease pose in Lao PDR. In particular, the analysis included estimation of the losses in the pork industry as well as losses due to human illness and lost productivity. A Markov-probability based decision-tree model was chosen to form the basis of the calculations to estimate the economic and public health impacts of taeniasis, trichinellosis and cysticercosis. Two different decision trees were run simultaneously on the model’s human cohort. A third decision tree simulated the potential impacts on pig production. The human capital method was used to estimate productivity loss. The results found varied significantly depending on the rate of hospitalisation due to neurocysticerosis. This study is the first systematic estimate of the economic impact of pig-associated zoonotic diseases in Lao PDR that demonstrates the significance of the diseases in that country. 相似文献
73.
Namrata Tomar Olivia Choudhury Ankush Chakrabarty Rajat K. De 《Molecular biology reports》2013,40(2):1103-1125
Biochemical networks comprise many diverse components and interactions between them. It has intracellular signaling, metabolic and gene regulatory pathways which are highly integrated and whose responses are elicited by extracellular actions. Previous modeling techniques mostly consider each pathway independently without focusing on the interrelation of these which actually functions as a single system. In this paper, we propose an approach of modeling an integrated pathway using an event-driven modeling tool, i.e., Petri nets (PNs). PNs have the ability to simulate the dynamics of the system with high levels of accuracy. The integrated set of signaling, regulatory and metabolic reactions involved in Saccharomyces cerevisiae’s HOG pathway has been collected from the literature. The kinetic parameter values have been used for transition firings. The dynamics of the system has been simulated and the concentrations of major biological species over time have been observed. The phenotypic characteristics of the integrated system have been investigated under two conditions, viz., under the absence and presence of osmotic pressure. The results have been validated favorably with the existing experimental results. We have also compared our study with the study of idFBA (Lee et al., PLoS Comput Biol 4:e1000–e1086, 2008) and pointed out the differences between both studies. We have simulated and monitored concentrations of multiple biological entities over time and also incorporated feedback inhibition by Ptp2 which has not been included in the idFBA study. We have concluded that our study is the first to the best of our knowledge to model signaling, metabolic and regulatory events in an integrated form through PN model framework. This study is useful in computational simulation of system dynamics for integrated pathways as there are growing evidences that the malfunctioning of the interplay among these pathways is associated with disease. 相似文献
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76.
In the present work, indigenously prepared rigid superporous (pore size of approximately 3 microm) cross-linked cellulose matrix (CELBEADS) has been used as a support for the immobilization of Bacillus licheniformis alpha-amylase (BLA). Optimum pH and temperature, and Michaelis-Menten constants were determined for both free and immobilized BLA. Immobilized BLA was observed to produce a different saccharide profile than free BLA at any value of dextrose equivalent. It was observed that pH, temperature, and initial starch concentration has a significant effect on the saccharide profile of starch hydrolysate produced using immobilized BLA in the batch mode, whereas the ratio of concentration of enzyme units to initial starch concentration has no influence on the same. Hence immobilized BLA can be used as an additional tool for production of maltodextrins with different saccharide profiles. Immobilized BLA has better thermostability than free BLA. Immobilized BLA was found to retain full activity even after eight batches of hydrolysis, each of 8h duration at 55 degrees C and 90 mg/mL initial starch concentration. A semiempirical model has been used for the prediction of saccharide composition of starch hydrolysate with respect to time. 相似文献
77.
Molecular Evidence for the Association of Tomato leaf curl Gujarat virus with a Leaf Curl Disease of Phaseolus vulgaris L. 下载免费PDF全文
Naimuddin Kamaal Mohammad Akram Aniruddha Kumar Agnihotri 《Journal of Phytopathology》2015,163(1):58-62
A leaf curl disease with symptoms typical of begomoviruses was observed in bean (Phaseolus vulgaris) at the Main Research Farm of the Indian Institute of Pulses Research, Kanpur, India. Infected plants had severe distortion of leaves and the plants were unproductive. PCR indicated the involvement of French bean leaf curl virus (JQ866297), a recently described Begomovirus, and Tomato leaf curl Gujarat virus (ToLCGV). The full‐length genome of ToLCGV associated with leaf curl disease of bean was 2757 nucleotides long and had maximum identity (97–98%) with seven isolates of ToLCGV (AY234383, AF449999, EU573714, GQ994098, AY190290, FR819708, AF413671) and is designated as Tomato leaf curl Gujarat virus‐(IN:Knp:Bean:2013) (KF440686). To the best of our knowledge, this is the first record of ToLCGV infecting a leguminous host, P. vulgaris. 相似文献
78.
Microsatellites are the markers of choice due to their high abundance reproducibility, degree of polymorphism and co-dominant nature. These are mainly used for studying the genetic variability in different species and Marker assisted selection. Expressed Sequence Tags (ESTs) serve as the main resource for Simple Sequence Repeats (SSRs). The computational approach for detecting SSRs and developing SSR markers from EST-SSRs is preferred over the conventional methods as it reduces time and cost to a great extent. The available EST sequence databases, various web interfaces and standalone tools provide the platform for an easy analysis of the EST sequences leading to the development of potential EST-SSR Markers. This paper is an overview of in silico approach to develop SSR Markers from the EST sequence using some of the most efficient tools that are available freely for academic purpose. 相似文献
79.
Dey N Das F Mariappan MM Mandal CC Ghosh-Choudhury N Kasinath BS Choudhury GG 《The Journal of biological chemistry》2011,286(29):25586-25603
Hyperglycemia induces a wide array of signaling pathways in the kidney that lead to hypertrophy and matrix expansion, eventually culminating in progressive kidney failure. High glucose-induced reduction of the tumor suppressor protein phosphatase and tensin homolog deleted in chromosome 10 (PTEN) contributes to renal cell hypertrophy and matrix expansion. We identified microRNA-21 (miR-21) as the molecular link between high glucose and PTEN suppression. Renal cortices from OVE26 type 1 diabetic mice showed significantly elevated levels of miR-21 associated with reduced PTEN and increased fibronectin content. In renal mesangial cells, high glucose increased the expression of miR-21, which targeted the 3'-UTR of PTEN mRNA to inhibit PTEN protein expression. Overexpression of miR-21 mimicked the action of high glucose, which included a reduction in PTEN expression and a concomitant increase in Akt phosphorylation. In contrast, expression of miR-21 Sponge, to inhibit endogenous miR-21, prevented down-regulation of PTEN and phosphorylation of Akt induced by high glucose. Interestingly, high glucose-stimulated miR-21 inactivated PRAS40, a negative regulator of TORC1. Finally, miR-21 enhanced high glucose-induced TORC1 activity, resulting in renal cell hypertrophy and fibronectin expression. Thus, our results identify a previously unrecognized function of miR-21 that is the reciprocal regulation of PTEN levels and Akt/TORC1 activity that mediate critical pathologic features of diabetic kidney disease. 相似文献
80.
Urinary excretion of hydroxycinnamates and flavonoids after oral and intravenous administration. 总被引:5,自引:0,他引:5
The urinary recoveries of the hydroxycinnamates, ferulic acid (3-methoxy, 4-hydroxy cinnamic acid), and chlorogenic acid (the quinic acid ester of 3,4-dihydroxycinnamic acid), and three structurally related flavonoids were studied in the rat. For the latter, the aglycone quercetin was compared with its 3-glucoside (isoquercitrin) and 3-rhamnoglucoside (rutin). Doses of 50 mg/kg were administered via the oral and intravenous routes and urine collected over the subsequent 24-h period. Reverse phase HPLC with photo-diode array detection was used to analyze the unchanged compound and their metabolites excreted in the urine. Ferulic acid and isoquercitrin were orally absorbed (5.4 and 0.48% of administered dose, respectively) and are therefore bioavailable. In contrast, neither unchanged chlorogenic acid, rutin, quercetin, nor the conjugated metabolites in the form of glucuronide or sulphate were detected in the urine after oral dosing. All the flavonoids studied produced low total urinary recoveries after intravenous administration, 9.2% for quercetin-3-rhamnoglucoside, 6.7% for the 3-glucoside, and 2.4% for the aglycone, indicating that extensive metabolism to low molecular weight compounds or excretion via other routes may be occurring. Overall it can be stated that renal excretion is not a major pathway of elimination for intact flavonoids and hydroxycinnamates in the rat. 相似文献