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371.
Raquel González Meghna Desai Eusebio Macete Peter Ouma Mwaka A. Kakolwa Salim Abdulla John J. Aponte Helder Bulo Abdunoor M. Kabanywanyi Abraham Katana Sonia Maculuve Alfredo Mayor Arsenio Nhacolo Kephas Otieno Golbahar Pahlavan María Rupérez Esperan?a Sevene Laurence Slutsker Anifa Vala John Williamsom Clara Menéndez 《PLoS medicine》2014,11(9)
Background
Intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP) is recommended for malaria prevention in HIV-negative pregnant women, but it is contraindicated in HIV-infected women taking daily cotrimoxazole prophylaxis (CTXp) because of potential added risk of adverse effects associated with taking two antifolate drugs simultaneously. We studied the safety and efficacy of mefloquine (MQ) in women receiving CTXp and long-lasting insecticide treated nets (LLITNs).Methods and Findings
A total of 1,071 HIV-infected women from Kenya, Mozambique, and Tanzania were randomized to receive either three doses of IPTp-MQ (15 mg/kg) or placebo given at least one month apart; all received CTXp and a LLITN. IPTp-MQ was associated with reduced rates of maternal parasitemia (risk ratio [RR], 0.47 [95% CI 0.27–0.82]; p = 0.008), placental malaria (RR, 0.52 [95% CI 0.29–0.90]; p = 0.021), and reduced incidence of non-obstetric hospital admissions (RR, 0.59 [95% CI 0.37–0.95]; p = 0.031) in the intention to treat (ITT) analysis. There were no differences in the prevalence of adverse pregnancy outcomes between groups. Drug tolerability was poorer in the MQ group compared to the control group (29.6% referred dizziness and 23.9% vomiting after the first IPTp-MQ administration). HIV viral load at delivery was higher in the MQ group compared to the control group (p = 0.048) in the ATP analysis. The frequency of perinatal mother to child transmission of HIV was increased in women who received MQ (RR, 1.95 [95% CI 1.14–3.33]; p = 0.015). The main limitation of the latter finding relates to the exploratory nature of this part of the analysis.Conclusions
An effective antimalarial added to CTXp and LLITNs in HIV-infected pregnant women can improve malaria prevention, as well as maternal health through reduction in hospital admissions. However, MQ was not well tolerated, limiting its potential for IPTp and indicating the need to find alternatives with better tolerability to reduce malaria in this particularly vulnerable group. MQ was associated with an increased risk of mother to child transmission of HIV, which warrants a better understanding of the pharmacological interactions between antimalarials and antiretroviral drugs.Trial registration
ClinicalTrials.gov ; NCT 00811421Pan African Clinical Trials Registry PACTR 2010020001813440 Please see later in the article for the Editors'' Summary 相似文献372.
Carolin R Loescher Tobias Gro?kopf Falguni D Desai Diana Gill Harald Schunck Peter L Croot Christian Schlosser Sven C Neulinger Nicole Pinnow Gaute Lavik Marcel M M Kuypers Julie LaRoche Ruth A Schmitz 《The ISME journal》2014,8(11):2180-2192
Nitrogen fixation, the biological reduction of dinitrogen gas (N2) to ammonium (NH4+), is quantitatively the most important external source of new nitrogen (N) to the open ocean. Classically, the ecological niche of oceanic N2 fixers (diazotrophs) is ascribed to tropical oligotrophic surface waters, often depleted in fixed N, with a diazotrophic community dominated by cyanobacteria. Although this applies for large areas of the ocean, biogeochemical models and phylogenetic studies suggest that the oceanic diazotrophic niche may be much broader than previously considered, resulting in major implications for the global N-budget. Here, we report on the composition, distribution and abundance of nifH, the functional gene marker for N2 fixation. Our results show the presence of eight clades of diazotrophs in the oxygen minimum zone (OMZ) off Peru. Although proteobacterial clades dominated overall, two clusters affiliated to spirochaeta and archaea were identified. N2 fixation was detected within OMZ waters and was stimulated by the addition of organic carbon sources supporting the view that non-phototrophic diazotrophs were actively fixing dinitrogen. The observed co-occurrence of key functional genes for N2 fixation, nitrification, anammox and denitrification suggests that a close spatial coupling of N-input and N-loss processes exists in the OMZ off Peru. The wide distribution of diazotrophs throughout the water column adds to the emerging view that the habitat of marine diazotrophs can be extended to low oxygen/high nitrate areas. Furthermore, our statistical analysis suggests that NO2− and PO43− are the major factors affecting diazotrophic distribution throughout the OMZ. In view of the predicted increase in ocean deoxygenation resulting from global warming, our findings indicate that the importance of OMZs as niches for N2 fixation may increase in the future. 相似文献
373.
Cisplatin, first (platinum) compound to be evolved as an anticancer agent, has found its important place in cancer chemotherapy. However, the dose-dependent toxicities of cisplatin, namely nephrotoxicity, ototoxicity, peripheral neuropathy, and gastrointestinal toxicity hinder its widespread use. Liposomes can reduce the toxicity of cisplatin and provide a better therapeutic action, but the low lipid solubility of cisplatin hinders its high entrapment in such lipid carrier. In the present investigation, positively charged reactive aquated species of cisplatin were complexed with negatively charged caprylate ligands, resulting in enhanced interaction of cisplatin with lipid bilayer of liposomes and increase in its encapsulation in liposomal carrier. Prepared cisplatin liposomes were found to have a vesicular size of 107.9 ± 6.2 nm and zeta potential of −3.99 ± 3.45 mV. The optimized liposomal formulation had an encapsulation efficiency of 96.03 ± 1.24% with unprecedented drug loading (0.21 mg cisplatin / mg of lipids). The in vitro release studies exhibited a pH-dependent release of cisplatin from liposomes with highest release (67.55 ± 3.65%) at pH 5.5 indicating that a maximum release would occur inside cancer cells at endolysosomal pH. The prepared liposomes were found to be stable in the serum and showed a low hemolytic potential. In vitro cytotoxicity of cisplatin liposomes on A549 lung cancer cell line was comparable to that of cisplatin solution. The developed formulation also had a significantly higher median lethal dose (LD50) of 23.79 mg/kg than that of the cisplatin solution (12 mg/kg). A promising liposomal formulation of cisplatin has been proposed that can overcome the disadvantages associated with conventional cisplatin therapy and provide a higher safety profile.Key Words: cisplatin, complexation, cytotoxicity, LD50, liposome 相似文献
374.
Subhankar Chakraborty D. Boominathan Ajay A. Desai T. N. C. Vidya 《Conservation Genetics》2014,15(4):897-907
With growing human and, possibly, elephant populations and a drastic increase in anthropogenic activities, human–elephant conflict in Asia has been on the rise. The Alur area in Karnataka state, southern India, is one such case in point, which has witnessed increasing levels of human–elephant conflict over the last two decades. The tiny, moderately protected habitat available for elephants in this human-dominated landscape does not appear to be able to support elephants over the long term. Options to deal with the escalating conflict include translocation of elephants, bringing elephants into captivity, and culling. We carried out a molecular genetic study of elephants in the Alur area to estimate the minimum number of elephants using the area, the sex ratio, genetic relatedness between individuals, and genetic structure with regard to the larger population in the landscape, so that informed management decisions could be made. Fresh dung samples were collected from the field and genotyped using 12 microsatellite loci. We found 29 unique individuals in the population, comprising 17 females and 12 males of different age classes. Relatedness between females suggested independent colonisations by discrete, small groups rather than by one cohesive clan of related females. This obviates the need for a single solution for dealing with all the females in the area in order to maintain social integrity, and has implications in terms how these elephants can be dealt with. We demonstrate how social organization inferred through molecular data from non-invasive sampling can inform management decisions. 相似文献
375.
376.
Liang Xie Qinming Zhou Shigang Liu Qingyuan Wu Yongjia Ji Lujun Zhang Fan Xu Wei Gong Narayan D. Melgiri Peng Xie 《PloS one》2014,9(1)
Background
The cynomolgus monkey (Macaca fascicularis) has been increasingly used as a non-human primate model in biomedical research. As establishing baseline thoracic radiography for the cynomolgus monkey is essential, we tested the hypothesis that age and sex may affect the thoracic radiography parameters of this species.Methods
Here, 697 healthy cynomolgus monkeys were segregated by sex and age (three age groups: 25–36 months, 37–48 months, 49–60 months). The lung length (LL), maximal interior thoracic depth (TD), maximal interior thoracic breadth (TBr), cardiac silhouette breadth (CBr), cardiothoracic ratio (CR), right and left costophrenic angles (RCA and LCA), and right hilar height ratio (R-HHR) were assessed by chest film. Statistical analysis was applied to examine the effect of age, sex, and age × sex interactions.Results
Significant effects by age were shown for LL, TD, TBr, CBr, and CR. Significant effects by sex were found for TD, TBr, CBr, CR, and R-HHR. Significant effects by age × sex were observed for TD, TBr, CBr, and CR. Both TD and TBr increased with age in both sexes, and both were significantly higher in males than in females in the group aged 49–60 months. CBr increased with age and was significantly higher in males than in females across all age groups. CR declined with age and was significantly higher in males than females across all age groups, and CR was similar or slightly higher relative to those previously found in other non-human primate species. As to the other parameters with no significant sex nor age-related differences, the R-HHR was greater than 1.00, and the angulation of bilateral costophrenic angles were sharp.Conclusions
The thoracic radiographic parameters for the healthy cynomolgus monkey presented here should prove useful in veterinary practice, research involving non-human primate models of respiratory or cardiovascular disorders, and morphological studies on cynomolgus monkeys. 相似文献377.
Archana Yadav Rajiv S. Desai Bansari A. Bhuta Jatinder S. Singh Reema Mehta Akash P. Nehete 《PloS one》2014,9(5)
Mast cells (MCs) expressing serine proteases; tryptase and chymase, are associated with fibrosis in various diseases. However, little is known about their involvement in oral submucous fibrosis (OSF). Our goal was to evaluate the role of MC tryptase and chymase in the pathogenesis of OSF and its malignant transformation. Immunohistochemical expression of MC tryptase and chymase was evaluated in 20 cases of OSF, 10 cases of oral squamous cell carcinoma (OSCC) and 10 cases of healthy controls. Subepithelial zone of Stage 1 and 2 while deep zone of Stage 3 and 4 OSF demonstrated increased tryptase positive MCs. OSCC revealed a proportionate increase in tryptase and chymase positive MCs irrespective of areas of distribution. An altered balance in the subepithelial and deep distribution of tryptase and chymase positive MCs play an important role in the pathogenesis of OSF and its malignant transformation. 相似文献
378.
Narayan Shivapurkar Louis M. Weiner John L. Marshall Subha Madhavan Anne Deslattes Mays Hartmut Juhl Anton Wellstein 《PloS one》2014,9(1)
Systemic treatment of patients with early-stage cancers attempts to eradicate occult metastatic disease to prevent recurrence and increased morbidity. However, prediction of recurrence from an analysis of the primary tumor is limited because disseminated cancer cells only represent a small subset of the primary lesion. Here we analyze the expression of circulating microRNAs (miRs) in serum obtained pre-surgically from patients with early stage colorectal cancers. Groups of five patients with and without disease recurrence were used to identify an informative panel of circulating miRs using quantitative PCR of genome-wide miR expression as well as a set of published candidate miRs. A panel of six informative miRs (miR-15a, mir-103, miR-148a, miR-320a, miR-451, miR-596) was derived from this analysis and evaluated in a separate validation set of thirty patients. Hierarchical clustering of the expression levels of these six circulating miRs and Kaplan-Meier analysis showed that the risk of disease recurrence of early stage colon cancer can be predicted by this panel of miRs that are measurable in the circulation at the time of diagnosis (P = 0.0026; Hazard Ratio 5.4; 95% CI of 1.9 to 15). 相似文献
379.
Objective
We investigated the role of state-level differences in modifiable cardiovascular (CV) risk factors in contributing to state disparities in cardiovascular mortality rates in the US.Methods
Adults aged 45–74 in 2010 were examined. We constructed a CV risk index summarizing state-level exposure to current smoking, obesity, physical inactivity, alcohol abstinence, hypertension, elevated cholesterol, and diabetes using the Behavioral Risk Factor Surveillance System. Outcomes were cardiovascular, coronary heart disease, and stroke mortality. Linear regression was used to estimate associations between the CV risk index and mortality outcomes. Models accounted for state-level socioeconomic characteristics and other potential confounders.Results
Risk factors were highly correlated at the state-level (Cronbach''s alpha 0.85 (men) and 0.92 (women). Each +1SD difference in the cardiovascular risk index was associated with higher adjusted cardiovascular mortality rates by 41.0 (95%CI = 26.3, 55.7) and 33.3 (95%CI = 24.4, 42.2) deaths per 100,000 for men and women, respectively. The index accounted for 8% (men) and 11% (women) of the variation in state-level cardiovascular mortality. Comparable associations were also observed for coronary heart disease and stroke mortality.Conclusions
CV risk factors were highly correlated at the state-level and were independently associated with state CV mortality, suggesting the utility of generalized CV risk reduction. 相似文献380.