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91.
Sumiti Vinayak Md Tauqeer Alam Tonya Mixson-Hayden Andrea M. McCollum Rithy Sem Naman K. Shah Pharath Lim Sinuon Muth William O. Rogers Thierry Fandeur John W. Barnwell Ananias A. Escalante Chansuda Wongsrichanalai Frederick Ariey Steven R. Meshnick Venkatachalam Udhayakumar 《PLoS pathogens》2010,6(3)
The Thailand-Cambodia border is the epicenter for drug-resistant falciparum malaria. Previous studies have shown that chloroquine (CQ) and pyrimethamine resistance originated in this region and eventually spread to other Asian countries and Africa. However, there is a dearth in understanding the origin and evolution of dhps alleles associated with sulfadoxine resistance. The present study was designed to reveal the origin(s) of sulfadoxine resistance in Cambodia and its evolutionary relationship to African and South American dhps alleles. We sequenced 234 Cambodian Plasmodium falciparum isolates for the dhps codons S436A/F, A437G, K540E, A581G and A613S/T implicated in sulfadoxine resistance. We also genotyped 10 microsatellite loci around dhps to determine the genetic backgrounds of various alleles and compared them with the backgrounds of alleles prevalent in Africa and South America. In addition to previously known highly-resistant triple mutant dhps alleles SGEGA and AGEAA (codons 436, 437, 540, 581, 613 are sequentially indicated), a large proportion of the isolates (19.3%) contained a 540N mutation in association with 437G/581G yielding a previously unreported triple mutant allele, SGNGA. Microsatellite data strongly suggest the strength of selection was greater on triple mutant dhps alleles followed by the double and single mutants. We provide evidence for at least three independent origins for the double mutants, one each for the SGKGA, AGKAA and SGEAA alleles. Our data suggest that the triple mutant allele SGEGA and the novel allele SGNGA have common origin on the SGKGA background, whereas the AGEAA triple mutant was derived from AGKAA on multiple, albeit limited, genetic backgrounds. The SGEAA did not share haplotypes with any of the triple mutants. Comparative analysis of the microsatellite haplotypes flanking dhps alleles from Cambodia, Kenya, Cameroon and Venezuela revealed an independent origin of sulfadoxine resistant alleles in each of these regions. 相似文献
92.
93.
Alam N 《Journal of biosocial science》2007,39(5):769-778
While a country's health policy aims to provide health services to all who need them, very little in known about unmet need for additional medical care from users' perspectives in Bangladesh. This study examined unmet medical need (defined as whether a mother felt that, to manage sickness, her child had required medical care that was not available, regardless of reasons and medical care sought) of 2123 under-15 sick children by illness and child's socioeconomic characteristics in rural Bangladesh. The 1996 Health and Socioeconomic Survey conducted in Matlab recorded children's chronic (a disease or a condition lasting 3 months or more) and acute (a disease or a condition with a rapid onset and a short, severe course) morbidity, medical care sought to combat illness and unmet needs for additional medical services in mothers' views to manage the illness. The survey also recorded household socioeconomic data. Logistic regression was used to examine the data. The results reveal that unmet needs for additional medical care were 5.4% for children with acute illnesses, and 30.2% for children with chronic illnesses. For chronic illnesses, seeking medical care to manage illness from any health provider outside the home reduced unmet medical needs. Economic inequalities existed for both acute and chronic illnesses: the odds ratio of unmet medical needs for sick children of the least poor households was 0.42 (95% CI: 0.28-0.64) times that for sick children of the very poor households. The critically high unmet needs for children's chronic morbidity reveal that the chronic disease control programme in Bangladesh needs urgent revisiting and strengthening. 相似文献
94.
Chomvarin C Namwat W Wongwajana S Alam M Thaew-Nonngiew K Sinchaturus A Engchanil C 《The Journal of General and Applied Microbiology》2007,53(4):229-237
Toxigenic Vibrio cholerae, the cause of cholera, is a native flora of the aquatic environment which is transmitted through drinking water and still remains the leading cause of morbidity and mortality in many developing countries including Thailand. The culture method (CM), which is routinely used for assessing water quality, has not proven as efficient as molecular methods because the notorious pathogen survives in water mostly in a non-culturable state. We employed duplex-polymerase chain reaction (duplex-PCR) for detection of tcpA and ctxA genes in toxigenic V. cholerae, and compared PCR detection with CM in various waters of Khon Kaen Municipality, Thailand. We also evaluated the effect of different pre-PCR conditions on the results of ctxA and tcpA detection including: 1) water filtered and enriched in alkaline peptone water (APW) for 3 h before PCR, 2) water filtered without enrichment before PCR, and 3) use of only enrichment in APW for 6 h before PCR. Of the 96 water samples (taken from waste-water, potable and waste-water from patients' houses, and from rivers) tested, 48 (50%) were positive for ctxA and tcpA by duplex-PCR, whereas only 29 (30%) were positive for V. cholerae by CM. Of the 29 V. cholerae isolated by CM, 2 (7%) were toxigenic V. cholerae belonging to serovar O1, while the rests were non-O1/ non-O139. Results revealed, therefore, that ctxA and tcpA-targeted duplex PCR is more sensitive than CM for detection of toxigenic V. cholerae from water samples because CM detected much less toxigenic V. cholerae than the non-toxigenic V. cholerae. Template DNA as low as 100 fg or 23 cells of V. cholerae in the water sample was detected in duplex PCR. Pre-PCR filtration followed by enrichment for 3 h significantly increase in the efficiency of duplex-PCR detection of toxigenic V. cholerae. 相似文献
95.
Daly-Burns B Alam TN Mackay A Clark J Shepherd CJ Rizzo S Tatoud R O'Hare MJ Masters JR Hudson DL 《Differentiation; research in biological diversity》2007,75(1):35-48
In the normal human prostate, undifferentiated proliferative cells reside in the basal layer and give rise to luminal secretory cells. There are, however, few epithelial cell lines that have a basal cell phenotype and are able to differentiate. We set out to develop a cell line with these characteristics that would be suitable for the study of the early stages of prostate epithelial cell differentiation. We produced a matched pair of conditionally immortalized prostate epithelial and stromal cell lines derived from the same patient. The growth of these cells is temperature dependent and differentiation can be induced following a rise in culture temperature. Three-dimensional co-cultures of these cell lines elicited gland-like structures reminiscent of prostatic acini. cDNA microarray analysis of the epithelial line demonstrated changes in gene expression consistent with epithelial differentiation. These genes may prove useful as markers for different prostate cell types. The cell lines provide a model system with which to study the process of prostatic epithelial differentiation and stromal-epithelial interactions. This may prove to be useful in the development of differentiation-targeted prostate cancer therapies. 相似文献
96.
Background
Mimivirus isolated from A. polyphaga is the largest virus discovered so far. It is unique among all the viruses in having genes related to translation, DNA repair and replication which bear close homology to eukaryotic genes. Nevertheless, only a small fraction of the proteins (33%) encoded in this genome has been assigned a function. Furthermore, a large fraction of the unassigned protein sequences bear no sequence similarity to proteins from other genomes. These sequences are referred to as ORFans. Because of their lack of sequence similarity to other proteins, they can not be assigned putative functions using standard sequence comparison methods. As part of our genome-wide computational efforts aimed at characterizing Mimivirus ORFans, we have applied fold-recognition methods to predict the structure of these ORFans and further functions were derived based on conservation of functionally important residues in sequence-template alignments.Results
Using fold recognition, we have identified highly confident computational 3D structural assignments for 21 Mimivirus ORFans. In addition, highly confident functional predictions for 6 of these ORFans were derived by analyzing the conservation of functional motifs between the predicted structures and proteins of known function. This analysis allowed us to classify these 6 previously unannotated ORFans into their specific protein families: carboxylesterase/thioesterase, metal-dependent deacetylase, P-loop kinases, 3-methyladenine DNA glycosylase, BTB domain and eukaryotic translation initiation factor eIF4E.Conclusion
Using stringent fold recognition criteria we have assigned three-dimensional structures for 21 of the ORFans encoded in the Mimivirus genome. Further, based on the 3D models and an analysis of the conservation of functionally important residues and motifs, we were able to derive functional attributes for 6 of the ORFans. Our computational identification of important functional sites in these ORFans can be the basis for a subsequent experimental verification of our predictions. Further computational and experimental studies are required to elucidate the 3D structures and functions of the remaining Mimivirus ORFans. 相似文献97.
Development and evaluation of acid-buffering bioadhesive vaginal tablet for mixed vaginal infections
An acid-buffering bioadhesive vaginal tablet was developed for the treatment of genitourinary tract infections. From the bioadhesion experiment and release studies it was found that polycarbophil and sodium carboxymethylcellulose is a good combination for an acid-buffering bioadhesive vaginal tablet. Sodium monocitrate was used as a buffering agent to provide acidic pH (4.4), which is an attribute of a healthy vagina. The effervescent mixture (citric acid and sodium bicarbonate) along with a superdisintegrant (Ac-Di-sol) was used to enhance the swellability of the bioadhesive tablet. The drugs clotrimazole (antifungal) and metronidazole (antiprotozoal as well as an antibacterial) were used in the formulation along with Lactobacillus acidophilus spores to treat mixed vaginal infections. From the ex vivo retention study it was found that the bioadhesive polymers hold the tablet for more than 24 hours inside the vaginal tube. The hardness of the acid-buffering bioadhesive vaginal tablet was optimized, at 4 to 5 kg hardness the swelling was found to be good and the cumulative release profile of the developed tablet was matched with a marketed conventional tablet (Infa-V). The in vitro spreadability of the swelled tablet was comparable to the marketed gel. In the in vitro antimicrobial study it was found that the acid-buffering bioadhesive tablet produces better antimicrobial action than marketed intravaginal drug delivery systems (Infa-V, Candid-V and Canesten 1). 相似文献
98.
Dawar Khadim Rahman Umar Alam Syed Sartaj Tariq Mohammad Khan Aamir Fahad Shah Datta Rahul Danish Subhan Saud Shah Noor Muhammad 《Journal of Plant Growth Regulation》2022,41(1):216-226
Journal of Plant Growth Regulation - The field experiment was conducted to investigate the effects of applying urea with nitrification inhibitor (NI) (Nitrapyrine) alone or in combination with... 相似文献
99.
Environmental Biology of Fishes - This is the first study conducted on the food and feeding habits of the yellowtail mullet (Minimugil cascasia), in the Ganga River (India). The gut contents of 276... 相似文献
100.
A high cell density transient transfection system for therapeutic protein expression based on a CHO GS‐knockout cell line: Process development and product quality assessment
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