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991.
Merozoite surface antigen-1 (MSA-1) of Plasmodium falciparum is highly immunogenic in human. Several studies suggest that MSA-1 protein is an effective target for a protective immune response. Attempt has been made to find new point mutations by analyzing 244 bp [codon 1655(R) to 1735 (I)] relatively conserved C-terminus region of MSA-1 gene in 125 isolates. This region contains two EGF like domains, which are involved in generating protective immune response in human. Point mutations in this region are very much important in view of vaccine development. Searching of mutational hot spots in MSA-1 protein by sequencing method in a representative number of isolates is quite critical and expensive. Therefore, in this study slot blot and PCR-SSCP method have been used to find out new mutations in the individual isolates showing alterations in the mobility of DNA fragment. Sequencing of the altered bands from the SSCP gel shows a rare non-synonymous point mutation in 7 (5.6%) of the 125 isolates at amino acid position 1704 of MSA-1 gene where isoleucine is replaced by valine. 相似文献
992.
Tuberculous pleuritis (TB) provides a good model to study the correlates of protective immune response at the site of infection. To study the in vivo correlates of immunity, cell subset profile and cytokine assay in plasma (BL) and pleural fluid (PF) of 82 patients were done. Lymphocyte proliferation and cytokine response to mycobacterial antigens were measured in 32 subjects to understand the in vitro correlates. Increase in CD4(+) cells and CD4(+)/CD8(+) ratio with selective concentration of interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha and interleukin (IL)-12 in PF suggests that the CD4(+) population may be of TH1 type. We observed an accelerated lymphoproliferative response to purified protein derivative (PPD) and heat killed Mycobacterium tuberculosis (MTB) in PF cells of both TB and non-TB (NTB) subjects. Interestingly, in in vitro studies, IL-4 levels together with IFN-gamma were significantly increased in the supernatants of PF mononuclear cells (PFMC) of TB patients and showed a shift in immune response towards TH0/TH2 type. PPD and MTB antigens induced an enhanced proliferation of PFMC and also increased in vitro IL-4 response together with apoptosis, thus eliciting a dual response. 相似文献
993.
Basak A Mandal S Kumar Das A Bertolasi V 《Bioorganic & medicinal chemistry letters》2002,12(6):873-877
Monocyclic enediynyl amides 2a-2c have been synthesized via the corresponding free amine 5. Kinetic studies in chloroform revealed the reactivity of these amides towards Bergman cyclization to be less than that of the corresponding sulfonamides. However, differential scanning calorimetry (DSC) measurements in the solid state and DNA-cleavage studies in aqueous buffer showed higher reactivity for the amides than the sulphonamides. 相似文献
994.
The uptake of water vapour by 20 different polyaminoacids have been evaluated by an isopiestic vapour pressure technique in absence of solute at three different temperatures (22 degrees C, 30 degrees C and 37 degrees C). The water vapour adsorption isotherm for different polyaminoacids in the range of water activity varying between zero and unity apparently agreed with that expected from a type III BET isotherm. From the linear BET plots, obeyed in the lower range of water activity, the BET constants n(m) and Qm for different polyamines have been evaluated. The amount of water vapour adsorbed (n1) was calculated in moles/kg of polyaminoacids as well as in moles/mole of amino acid residue. Its value at unit water activity (deltan(o)1) has been evaluated by an extrapolation method and the results support that the multilayer adsorption of water vapour at the interface of polyaminoacids takes place. Values of deltan(o)1 are strictly comparable in terms of moles per kg rather than mole per mole unit. In case of beta lactoglobulin (betalg), lysozyme and BSA, theoretically obtained deltan(o)1 values were observed to be considerably larger than experimental values of deltan(o)1. This indicated that amino acid residues in the polypeptide release a large amount of water due to the formation of a globular structure. Using the Bull equation in the integrated form, standard free energies, deltaGo(w) for water-polyamino acid binding interaction at two different temperatures have been evaluated. Based on the Clausius-Clapeyron equation in an integrated form, the integral enthalpy for water-polyamino acid interaction has also been evaluated. 相似文献
995.
Vertical Profile of Phosphatase Activity in the Sundarban Mangrove Forest,North East Coast of Bay of Bengal,India 总被引:2,自引:0,他引:2
Impact of phosphate solubilizing bacteria along with soil phosphatase activity on phosphorous cycle was found to be quiet interesting in the Sundarban mangrove ecosystem. Soil phosphatase activity showed a decreasing pattern with increase in depth [soil phosphatase activity (μg pnp produced g?1 dry wt of soil) = 906.85 – 5.6316 Depth (cm)] from the deep forest region of the Sundarban forest ecosystem. Soil salinity showed a very little effect on soil phosphatase activity whereas soil temperature and pH was found to show significant impact on the soil phosphatase activity. This ensured that the microbes associated with phosphate mineralization present in the Sundarban forest ecosystem are more tolerant to fluctuation in salinity than that of temperature and pH. A direct correlation was perceptible between the number of phosphate solubilizing bacteria and phosphatase activity in the soil during the study period from 2007 to 2012. Soil phosphate concentration was found to be directly governed by the soil phosphatase activity [The regression equation is: avg PO4?3-P (μg g?1 dry wt of soil) = 0.0311 + 0.000606 soil phosphatase activity (μg pnp produced g?1 dry wt of soil); R2 = 63.2%, p < 0.001, n = 62]. 相似文献
996.
Huguette Gaelle Ngassa Mbenda Gauri Awasthi Poonam K Singh Inocent Gouado Aparup Das 《Journal of biosciences》2014,39(4):727-738
Cameroon, a west-central African country with a ~20 million population, is commonly regarded as ‘Africa in miniature’ due to the extensive biological and cultural diversities of whole Africa being present in a single-country setting. This country is inhabited by ancestral human lineages in unique eco-climatic conditions and diverse topography. Over 90% Cameroonians are at risk of malaria infection, and ~41% have at least one episode of malaria each year. Historically, the rate of malaria infection in Cameroon has fluctuated over the years; the number of cases was about 2 million in 2010 and 2011. The Cameroonian malaria control programme faces an uphill task due to high prevalence of multidrug-resistant parasites and insecticide-resistant malaria vectors. Above all, continued human migration from the rural to urban areas as well as population exchange with adjoining countries, high rate of ecological instabilities caused by deforestation, poor housing, lack of proper sanitation and drainage system might have resulted in the recent increase in incidences of malaria and other vector-borne diseases in Cameroon. The available data on eco-environmental variability and intricate malaria epidemiology in Cameroon reflect the situation in the whole of Africa, and warrant the need for in-depth study by using modern surveillance tools for meaningful basic understanding of the malaria triangle (host-parasite-vector-environment). 相似文献
997.
Jaseetha Abdul Salam Nilanjana Das 《World journal of microbiology & biotechnology》2014,30(4):1301-1313
A new yeast strain was isolated from sugarcane cultivation field which was able to utilize lindane as sole carbon source for growth in mineral medium. The yeast was identified and named as Candida sp. VITJzN04 based on a polyphasic approach using morphological, biochemical and 18S rDNA, D1/D2 and ITS sequence analysis. The isolated yeast strain efficiently degraded 600 mg L?1 of lindane within 6 days in mineral medium under the optimal conditions (pH 7; temperature 30 °C and inoculum dosage 0.06 g L?1) with the least half-life of 1.17 days and degradation constant of 0.588 per day. Lindane degradation was tested with various kinetic models and results revealed that the reaction could be described best by first-order and pseudo first-order models. In addition, involvement of the enzymes viz. dechlorinase, dehalogenase, dichlorohydroquinone reductive dechlorinase, lignin peroxidase and manganese peroxidase was noted during lindane degradation. Addition of H2O2 in the mineral medium showed 32 % enhancement of lindane degradation within 3 days. Based on the metabolites identified by GC–MS and FTIR analysis, sequential process of lindane degradation by Candida VITJzN04 was proposed. To the best of our knowledge, this is the first report of isolation and characterization of lindane-degrading Candida sp. and elucidation of enzyme systems during the degradation process. 相似文献
998.
A. Selvi Jaseetha Abdul Salam Nilanjana Das 《World journal of microbiology & biotechnology》2014,30(11):2839-2850
Cefdinir, a semi-synthetic third generation cephalosporin antibiotic being considered as an emerging pollutant, demands removal from aquatic ecosystems. A yeast strain isolated from pharmaceutical wastewater which was identified as Ustilago sp. SMN03 by molecular techniques and was found to be capable of utilizing cefdinir as a sole carbon source. The isolate was found to degrade 81 % of cefdinir within 6 days under optimized conditions viz. pH 6.0, temperature 30 °C, a shaking speed of 120 rpm, an inoculum dosage of 4 % (w/v) and an initial cefdinir concentration of 200 mg L?1. Kinetic studies revealed that cefdinir degradation followed the pseudo-first order model, a rate constant of 0.222 per day and a half-life period of 3.26 days. Using LC–MS analysis, six novel intermediates formed during the cefdinir degradation were identified and characterized. FT-IR analysis showed that the functional groups ranging from 1,766 to 1,519 cm?1, characteristic for lactam ring were completely removed during the cefdinir degradation. The opening of the β-lactam ring was one of the major steps in the cefdinir degradation process. Based on the results from the present study, a possible pathway of cefdinir degradation by Ustilago sp. SMN03 was proposed. To the best of our knowledge, this is the first report on microbial degradation of cefdinir by yeast. 相似文献
999.
Prakash?Chandra?JoshiEmail author Mirak?Raj?Angdembe Sumon?Kumar?Das Shahnawaz?Ahmed Abu?Syed?Golam?Faruque Tahmeed?Ahmed 《International breastfeeding journal》2014,9(1):7
Background
Exclusive breastfeeding (EBF) means that the infant receives only breast milk for the first six months of life after birth. In Bangladesh, the prevalence of EBF remained largely unchanged for nearly two decades and was 43% in 2007. However, in 2011, a prevalence of 64% was reported, an increase by 21 percentage points. The reasons for this large change remain speculative at this point. Thus to investigate the issue further, this study was conducted. The objective was to assess the prevalence of EBF and associated factors among mothers having children aged 0–6 months in rural Bangladesh.Methods
A cross-sectional study was conducted in Mirzapur Upazilla (sub district) among 121 mothers of infants aged 0–6 months. Eligible mothers were identified and randomly selected using the demographic surveillance system’s computerized database that is updated weekly. A semi-structured questionnaire was used for interviews that inquired information on socio-demographic characteristics, obstetric, health service, breastfeeding related factors (initiation of breastfeeding, prelacteal feeding and colostrum feeding) and economic factors. EBF prevalence was calculated using 24 hour recall method. In multivariate analysis, a logistic regression model was developed using stepwise modeling to analyze the factors associated with EBF.Results
The prevalence of EBF in the last 24 hours preceding the survey was 36%. Bivariate and multivariate analysis revealed no significant association between EBF and its possible predictors at 0.05 level of alpha. However, there was some evidence of an association between EBF and having a caesarean delivery (OR?=?0.47, 95% CI: 0.21, 1.06). In multivariate analysis, type of delivery: caesarean (AOR?=?0.45, 95% CI: 0.19, 1.03) and wealth quintile: richer (AOR?=?2.40, 95% CI: 0.94, 6.16) also showed some evidence of an association with EBF.Conclusion
The prevalence of EBF in Mirzapur (36%) is lower than the national figure (64%). Prelacteal feeding was not uncommon. These findings suggest that there is a need for breastfeeding support provided by health services. Hence, promotion of EBF during the first six months of life needs to be addressed and future breastfeeding promotion programmes should give special attention to those women who are not practicing EBF.1000.
Lorraine Iacovitti Xiaotao Wei Jingli Cai Eric W. Kostuk Ruihe Lin Alexander Gorodinsky Philip Roman Gretchen Kusek Sonal S. Das Audrey Dufour Terina N. Martinez Kuldip D. Dave 《PloS one》2014,9(12)
Parkinson disease (PD) is the second leading neurodegenerative disease in the US. As there is no known cause or cure for PD, researchers continue to investigate disease mechanisms and potential new therapies in cell culture and in animal models of PD. In PD, one of the most profoundly affected neuronal populations is the tyrosine hydroxylase (TH)-expressing dopaminergic (DA) neurons of the substantia nigra pars compacta (SNpc). These DA-producing neurons undergo degeneration while neighboring DA-producing cells of the ventral tegmental area (VTA) are largely spared. To aid in these studies, The Michael J. Fox Foundation (MJFF) partnered with Thomas Jefferson University and Taconic Inc. to generate new transgenic rat lines carrying the human TH gene promoter driving EGFP using a 11 kb construct used previously to create a hTH-GFP mouse reporter line. Of the five rat founder lines that were generated, three exhibited high level specific GFP fluorescence in DA brain structures (ie. SN, VTA, striatum, olfactory bulb, hypothalamus). As with the hTH-GFP mouse, none of the rat lines exhibit reporter expression in adrenergic structures like the adrenal gland. Line 12141, with its high levels of GFP in adult DA brain structures and minimal ectopic GFP expression in non-DA structures, was characterized in detail. We show here that this line allows for anatomical visualization and microdissection of the rat midbrain into SNpc and/or VTA, enabling detailed analysis of midbrain DA neurons and axonal projections after toxin treatment in vivo. Moreover, we further show that embryonic SNpc and/or VTA neurons, enriched by microdissection or FACS, can be used in culture or transplant studies of PD. Thus, the hTH-GFP reporter rat should be a valuable tool for Parkinson''s disease research. 相似文献