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1.
McKeown SC Hall A Giblin GM Lorthioir O Blunt R Lewell XQ Wilson RJ Brown SH Chowdhury A Coleman T Watson SP Chessell IP Pipe A Clayton N Goldsmith P 《Bioorganic & medicinal chemistry letters》2006,16(18):4767-4771
The discovery, synthesis and structure-activity relationship (SAR) of a novel series of EP1 receptor antagonists is described. Pyrazole acid 4, identified from a chemical array, had desirable physicochemical properties, an excellent in vitro microsomal inhibition and cytochrome P450 (CYP450) profile and good exposure levels in blood. This compound had an ED50 of 1.3 mg/kg in a rat pain model. A range of more potent analogues in the in vitro assay was identified using efficient array chemistry. These EP1 antagonists have potential as agents in the treatment of PGE2 mediated pain. 相似文献
2.
Rafiqul I. Chowdhury Mohammed Ataharul Islam 《Biometrical journal. Biometrische Zeitschrift》2020,62(4):898-915
Life expectancy is increasing in many countries and this may lead to a higher frequency of adverse health outcomes. Therefore, there is a growing demand for predicting the risk of a sequence of events based on specified factors from repeated outcomes. We proposed regressive models and a framework to predict the joint probabilities of a sequence of events for multinomial outcomes from longitudinal studies. The Markov chain is used to link marginal and sequence of conditional probabilities to predict the joint probability. Marginal and sequence of conditional probabilities are estimated using marginal and regressive models. An application is shown using the Health and Retirement Study data. The bias of parameter estimates for all models from all bootstrap simulation is less than 1% in most of the cases. The estimated mean squared error is also very low. Results from the simulation study show negligible bias and the usefulness of the proposed model. The proposed model and framework would be useful to solve real-life problems from various fields and big data analysis. 相似文献
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Shams Forruque Ahmed;Fatema Mehejabin;Ashfaque Ahmed Chowdhury;Fares Almomani;Nadeem A. Khan;Irfan Anjum Badruddin;Sarfaraz Kamangar; 《Global Change Biology Bioenergy》2024,16(8):e13175
Biochar possesses unique characteristics, including a substantial surface area, a high carbon content, sufficient capacity for cation exchange, and a robust structure. However, biochar contains hazardous pollutants like volatile organic compounds that harm soil properties and functionality. Although several studies on biochar production from various feedstocks have been undertaken in recent years, several issues about feedstock preparation, economic feasibility, influencing factors, and the proper utilization of biochar production processes need to be addressed. This paper thus addresses these issues by providing potential solutions identified through a comprehensive review. Slow pyrolysis of lignocellulosic biomass and Acacia nilotica yields biochar from 20 to 52 wt% at various temperatures and residence times. Biochar yield varies from 29 to 48.3 wt% when waste tires and corn stalks are rapidly pyrolyzed at higher temperatures and for shorter periods. Torrefaction of algal biomass at moderate temperatures with different residence times can result in a substantial yield of 50–60 wt%. However, the variability and heterogeneity of waste feedstocks pose potential challenges affecting biochar's quality and properties. Given its widespread use in carbon sequestration, soil remediation, wastewater purification, and organic waste composting, the mechanisms of biochar production in environmental usage need to be investigated. 相似文献
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Stephen P. East Clara Bantry White Oliver Barker Stephanie Barker James Bennett David Brown E. Andrew Boyd Christopher Brennan Chandana Chowdhury Ian Collins Emmanuelle Convers-Reignier Brian W. Dymock Rowena Fletcher David J. Haydon Mihaly Gardiner Stuart Hatcher Peter Ingram Paul Lancett Paul Mortenson Konstantinos Papadopoulos Lloyd G. Czaplewski 《Bioorganic & medicinal chemistry letters》2009,19(3):894-899
The synthesis and antibacterial activities of three chemotypes of DNA supercoiling inhibitors based on imidazolo[1,2-a]pyridine and [1,2,4]triazolo[1,5-a]pyridine scaffolds that target the ATPase subunits of DNA gyrase and topoisomerase IV (GyrB/ParE) is reported. The most potent scaffold was selected for optimization leading to a series with potent Gram-positive antibacterial activity and a low resistance frequency. 相似文献
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Chowdhury SF Guerrero RH Brun R Ruiz-Perez LM Pacanowska DG Gilbert IH 《Journal of enzyme inhibition and medicinal chemistry》2002,17(5):293-302
Dihydrofolate reductase is a drug target that has not been thoroughly investigated in leishmania and trypanosomes. Work has previously shown that 5-benzyl-2,4-diaminopyrimidines are selective inhibitors of the leishmanial and trypanosome enzymes. Modelling predicted that alkyl/aryl substitution on the 6-position of the pyrimidine ring should increase enzyme activity of 5-benzyl-2,4-diaminopyrimidines as inhibitors of leishmanial and trypanosomal dihydrofolate reductase. Various compounds were prepared and evaluated against both the recombinant enzymes and the intact organisms. The presence of a substituent had a small or negative effect on activity against the enzyme or intact parasites compared to unsubstituted compounds. 相似文献
9.
Effect of osmolytes and chaperone-like action of P-protein on folding of nucleocapsid protein of Chandipura virus. 总被引:10,自引:0,他引:10
A Majumder S Basak T Raha S P Chowdhury D Chattopadhyay S Roy 《The Journal of biological chemistry》2001,276(33):30948-30955
Amino acid sequences of nucleocapsid proteins are mostly conserved among different rhabdoviruses. The protein plays a common functional role in different RNA viruses by enwrapping the viral genomic RNA in an RNase-resistant form. Upon expression of the nucleocapsid protein alone in COS cells and in bacteria, it forms large insoluble aggregates. In this work, we have reported for the first time the full-length cloning of the N gene of Chandipura virus and its expression in Escherichia coli in a soluble monomeric form and purification using nonionic detergents. The biological activity of the soluble recombinant protein has been tested, and it was found to possess efficient RNA-binding ability. The state of aggregation of the recombinant protein was monitored using light scattering. In the absence of nonionic detergents, it formed large aggregates. Aggregation was significantly reduced in the presence of osmolytes such as d-sorbitol. Aggregate formation was suppressed in the presence of another viral product, phosphoprotein P, in a chaperone-like manner. Both the osmolyte and phosphoprotein P also suppressed aggregation to a great extent during refolding from a guanidine hydrochloride-denatured form. The function of the phosphoprotein and osmolyte appears to be synergistic to keep the N-protein in a soluble biologically competent form in virus-infected cells. 相似文献
10.
Various national surveys suggest that the % of eligible couples in Bangladesh who are using traditional methods of contraception has been growing. This article presents detailed information on knowledge and use patterns of traditional methods and compares the use patterns of traditional and modern methods of contraception. The data are derived from the 1981 Contraceptive Prevalence Survey and information collected from a nationally representative sample of ever married women aged under 50, by way of field interviews using female interviewers. Quality of data was checked at different phases of the survey. Over 96% of the women reported that they knew at least 1 traditional method of contraception. The safe period was the most well known method (36.5%); about 30% reported knowledge of abstinence and 22% knew about withdrawal. Compared with modern methods, where knowledge declined with increased age, the knowledge of traditional methods shows no systematic pattern by age. Respondents with primary and higher education have higher knowledge of traditional methods than women who have never been to school. A similar pattern exists for employment status; non-Muslim women have consistently higher levels of knowledge than Muslim women. Data on patterns of use suggest that about 36% have used at least 1 contraceptive method, 15% having used traditional methods and 20.4% modern methods. The number of women who have used traditional methods increases from ages 20 to 44 and then declines. Use of traditional methods is relatively higher by the number of living children than by the number of children ever born. A similar pattern of association between background characteristics (education, employment and religion) and contraceptive knowledge is evident regarding level of use. Husband's level of education does not show any significant relationship with the use of traditional methods. The use rate of traditional methods was more than doubled among the women owning land compared to those having no land. The total current use rate of modern methods was higher among women aged 40-44 having relatively higher numbers of living children. As with current use, a positive relationship was observed between the socioeconomic variables and ever use. In general, it is concluded that socioeconomic variables played a dominant role in the decision of couples in choosing various methods of contraception. It is suggested that traditional methods still have an important role in family planning and that this should not be disregarded. 相似文献