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991.
R Baddam KL Thong TS Avasthi S Shaik KP Yap CS Teh LC Chai N Kumar N Ahmed 《Journal of bacteriology》2012,194(18):5122-5123
Many of the developing countries of the Southeast Asian region are significantly affected by endemic typhoid fever, possibly as a result of marginal living standards. It is an important public health problem in countries such as Papua New Guinea, which is geographically close to some of the foci of endemicity in Asia. The severity of the disease varies in different regions, and this may be attributable to genetic diversity among the native strains. Genome sequence data on strains from different countries are needed to clearly understand their genetic makeup and virulence potential. We describe the genomes of two Salmonella Typhi isolates from patients with fatal and nonfatal cases of typhoid fever in Papua New Guinea. We discuss in brief the underlying sequencing methodology, assembly, genome statistics, and important features of the two draft genomes, which form an essential step in our functional molecular infection epidemiology program centering on typhoid fever. The comparative genomics of these and other isolates would enable us to identify genetic rearrangements and mechanisms responsible for endemicity and the differential severity of pathogenic salmonellae in Papua New Guinea and elsewhere. 相似文献
992.
Kamal A Srikanth YV Ramaiah MJ Khan MN Kashi Reddy M Ashraf M Lavanya A Pushpavalli SN Pal-Bhadra M 《Bioorganic & medicinal chemistry letters》2012,22(1):571-578
A series of bisindole-pyrrolobenzodiazepine conjugates (5a-f) linked through different alkane spacers was prepared and evaluated for their anticancer activity. All compounds exhibited significant anticancer potency and the most potent compounds 5b and 5e were taken up for detailed studies on MCF-7 cell line. Cell cycle effects were examined apart from investigating the inhibition of tubulin polymerization for compounds 2a, 2b, 5b and 5e at 2μM. FACS analysis showed that at higher concentrations (4 and 8μM) there was an increase of sub-G1 phase cells and decrease of G2/M phase cells, thus indicating that compounds 5b and 5e are effective in causing apoptosis in MCF-7 cells. It was also observed that compounds 5b and 5e showed the down regulation of histone deacetylase protein levels such as HDAC1, 2, 3, 8 and increase in the levels of p21, followed by apoptotic cell death. The apoptotic nature of these compounds was further evidenced by increased expression of cleaved-PARP and active caspase-7 in MCF-7 cells. 相似文献
993.
Blastocystis infection has a worldwide distribution especially among the disadvantaged population and immunocompromised subjects. This study was carried out to determine the prevalence and the association of Blastocystis infection with the socio-economic characteristics among 300 primary schoolchildren, living in rural communities in Lipis and Raub districts of Pahang state, Malaysia. Stool samples were collected and examined for the presence of Blastocystis using direct smear microscopy after in vitro cultivation in Jones' medium. The overall prevalence of Blastocystis infection was found to be as high as 25.7%. The prevalence was significantly higher among children with gastrointestinal symptoms as compared to asymptomatic children (x2 =4.246; P=0.039). Univariate and multivariate analyses showed that absence of a piped water supply (OR=3.13; 95% CI=1.78, 5.46; P<0.001) and low levels of mothers' education (OR=3.41; 95% CI=1.62, 7.18; P<0.01) were the significant predictors of Blastocystis infection. In conclusion, Blastocystis is prevalent among rural children and the important factors that determine the infection were the sources of drinking water and mothers' educational level. Interventions with provision of clean water supply and health education especially to mothers are required. 相似文献
994.
Ismail HA Quan JH Wei Z Choi IW Cha GH Shin DW Lee YH Song CJ 《The Korean journal of parasitology》2012,50(1):7-13
Toxoplasma gondii can modulate host cell gene expression; however, determining gene expression levels in intermediate hosts after T. gondii infection is not known much. We selected 5 genes (ALDH1A2, BEX2, CCL3, EGR2 and PLAU) and compared the mRNA expression levels in the spleen, liver, lung and small intestine of genetically different mice infected with T. gondii. ALDH1A2 mRNA expressions of both mouse strains were markedly increased at day 1-4 postinfection (PI) and then decreased, and its expressions in the spleen and lung were significantly higher in C57BL/6 mice than those of BALB/c mice. BEX2 and CCR3 mRNA expressions of both mouse strains were significantly increased from day 7 PI and peaked at day 15-30 PI (P<0.05), especially high in the spleen liver or small intestine of C57BL/6 mice. EGR2 and PLAU mRNA expressions of both mouse strains were significantly increased after infection, especially high in the spleen and liver. However, their expression patterns were varied depending on the tissue and mouse strain. Taken together, T. gondii-susceptible C57BL/6 mice expressed higher levels of these 5 genes than did T. gondii-resistant BALB/c mice, particularly in the spleen and liver. And ALDH1A2 and PLAU expressions were increased acutely, whereas BEX2, CCL3 and EGR2 expressions were increased lately. Thus, these demonstrate that host genetic factors exert a strong impact on the expression of these 5 genes and their expression patterns were varied depending on the gene or tissue. 相似文献
995.
Fine mapping of QTLs for rice grain yield under drought reveals sub-QTLs conferring a response to variable drought severities 总被引:1,自引:0,他引:1
Dixit S Swamy BP Vikram P Ahmed HU Sta Cruz MT Amante M Atri D Leung H Kumar A 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,125(1):155-169
Fine-mapping studies on four QTLs, qDTY(2.1), qDTY(2.2), qDTY(9.1) and qDTY(12.1), for grain yield (GY) under drought were conducted using four different backcross-derived populations screened in 16 experiments from 2006 to 2010. Composite and bayesian interval mapping analyses resolved the originally identified qDTY(2.1) region of 42.3 cM into a segment of 1.6 cM, the qDTY(2.2) region of 31.0 cM into a segment of 6.7 cM, the qDTY(9.1) region of 32.1 cM into two segments of 9.4 and 2.4 cM and the qDTY(12.1) region of 10.6 cM into two segments of 3.1 and 0.4 cM. Two of the four QTLs (qDTY(9.1) and qDTY(12.1)) having effects under varying degrees of stress severity showed the presence of more than one region within the original QTL. The study found the presence of a donor allele at RM262 within qDTY(2.1) and RM24334 within qDTY(9.1) showing a negative effect on GY under drought, indicating the necessity of precise fine mapping of QTL regions before using them in marker-assisted selection (MAS). However, the presence of sub-QTLs together in close vicinity to each other provides a unique opportunity to breeders to introgress such regions together as a unit into high-yielding drought-susceptible varieties through MAS. 相似文献
996.
Ben Ahmed M Zaraa I Rekik R Elbeldi-Ferchiou A Kourda N Belhadj Hmida N Abdeladhim M Karoui O Ben Osman A Mokni M Louzir H 《Pigment cell & melanoma research》2012,25(1):99-109
Auto-reactive cytotoxic T lymphocytes play a key role in the progressive loss or destruction of melanocytes in vitiligo but the mechanism underlying the loss of self-tolerance is unknown. A deregulation of regulatory T-cell biology has recently been suggested. The analysis of the suppressive effects of peripheral T regulatory cells in vitiligo patients revealed a functional defect in seven of 15 cases. This defect was strongly correlated with disease activity. The evaluation of the percentage of peripheral regulatory T lymphocytes did not reveal any intrinsic quantitative defect. Yet, a decrease in the percentage of such cells was noted in patients with progressive forms, suggesting a recruitment of regulatory T cells from the peripheral blood to the site of injury. This was further corroborated by the significant increase of Forkhead box P3 expression in the vitiliginous skin of patients. Our data support the involvement of a functional defect of peripheral regulatory T cells in the pathogenesis of vitiligo and open new possibilities to advance therapeutic approaches. 相似文献
997.
ABSTRACT: BACKGROUND: PubMed is a free web literature search service that contains almost 21 millions of abstracts and publications with almost 5 million user queries daily. The purposes of the study were to compare trends in PubMed-indexed cancer and biomedical publications from Egypt to that of the world and to predict future publication volumes. METHODS: The PubMed was searched for the biomedical publications between 1991 and 2010 (publications dates). Affiliation was then limited to Egypt. Further limitation was applied to cancer, human and animal publications. Poisson regression model was used for prediction of future number of publications between 2011 and 2020. RESULTS: Cancer publications contributed 23% to biomedical publications both for Egypt and the world. Egyptian biomedical and cancer publications contributed about 0.13% to their world counterparts. This contribution was more than doubled over the study period. Egyptian and world's publications increased from year to year with rapid rise starting the year 2003. Egyptian as well as world's human cancer publications showed the highest increases. Egyptian publications had some peculiarities; they showed some drop at the years 1994 and 2002 and apart from the decline in the animal: human ratio with time, all Egyptian publications in the period 1991-2000 were significantly more than those in 2001-2010 (P<0.05 for all). By 2020, Egyptian biomedical and cancer publications will increase by 158.7% and 280% relative to 2010 to constitute 0.34% and 0.17% of total PubMed publications, respectively. CONCLUSIONS: The Egyptian contribution to world's biomedical and cancer publications needs significant improvements through research strategic planning, setting national research priorities, adequate funding and researchers' training. 相似文献
998.
Jedy-Agba EE Curado MP Oga E Samaila MO Ezeome ER Obiorah C Erinomo OO Ekanem IO Uka C Mayun A Afolayan EA Abiodun P Olasode BJ Omonisi A Otu T Osinubi P Dakum P Blattner W Adebamowo CA 《Cancer epidemiology》2012,36(5):430-435
Background: The incidence of cancer continues to rise all over the world and current projections show that there will be 1.27 million new cases and almost 1 million deaths by 2030. In view of the rising incidence of cancer in sub-Saharan Africa, urgent steps are needed to guide appropriate policy, health sector investment and resource allocation. We posit that hospital based cancer registries (HBCR) are fundamental sources of information on the frequent cancer sites in limited resource regions where population level data is often unavailable. In regions where population based cancer registries are not in existence, HBCR are beneficial for policy and planning. Materials and methods: Nineteen of twenty-one cancer registries in Nigeria met the definition of HBCR, and from these registries, we requested data on cancer cases recorded from January 2009 to December 2010. 16 of the 19 registries (84%) responded. Data on year hospital was established; year cancer registry was established, no. of pathologists and types of oncology services available in each tertiary health facility were shown. Analysis of relative frequency of cancers in each HBCR, the basis of diagnosis recorded in the HBCR and the total number of cases recorded by gender was carried out. Results: The total number of cancers registered in these 11 hospital based cancer registries in 2009 and 2010 was 6484. The number of new cancer cases recorded annually in these hospital based cancer registries on average was 117 cases in males and I77 cases in females. Breast and cervical cancer were the most common cancers seen in women while prostate cancer was the commonest among men seen in these tertiary hospitals. Conclusion: Information provided by HBCR is beneficial and can be utilized for the improvement of cancer care delivery systems in low and middle income countries where there are no population based cancer registries. 相似文献
999.
Ramanathan?K?KasimanickamEmail author Vanmathy?R?Kasimanickam Gary?J?Haldorson Ahmed?Tibary 《Reproductive biology and endocrinology : RB&E》2012,10(1):4
Background
Interleukins (IL) play an important role in angiogenesis. Tocopherol possesses immunomodulating effect in addition to antioxidant property. The objective of this study was to determine whether gamma tocopherol's (gT) angiogenic activity in placental network is enhanced via promoting interleukins. 相似文献1000.