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881.
Bun Poh Keong Siti Shapor Siraj Siti Khalijah Daud Jothi Malar Panandam Arina Nadia Abdul Rahman 《Gene》2014
A preliminary linkage map was constructed by applying backcross and testcross strategy using microsatellite (SSR) markers developed for Xiphophorus and Poecilia reticulata in ornamental fish, molly Poecilia sp. The linkage map having 18 SSR loci consisted of four linkage groups that spanned a map size of 516.1 cM. Association between genotypes and phenotypes was tested in a random fashion and QTL for dorsal fin length was found to be linked to locus Msb069 on linkage group 2. Coincidentally, locus Msb069 was also reported as putative homologue primer pairs containing SSRs repeat motif which encoded hSMP-1, a sex determining locus. Dorsal fin length particularly in males of Poecilia latipinna is an important feature during courtship display. Therefore, we speculate that both dorsal fin length and putative hSMP-1 gene formed a close proximity to male sexual characteristics. 相似文献
882.
Likely changes in precipitation (P) and potential evapotranspiration (PET) resulting from policy-driven expansion of bioenergy crops in the United States are shown to create significant changes in streamflow volumes and increase water stress in the High Plains. Regional climate simulations for current and biofuel cropping system scenarios are evaluated using the same atmospheric forcing data over the period 1979–2004 using the Weather Research Forecast (WRF) model coupled to the NOAH land surface model. PET is projected to increase under the biofuel crop production scenario. The magnitude of the mean annual increase in PET is larger than the inter-annual variability of change in PET, indicating that PET increase is a forced response to the biofuel cropping system land use. Across the conterminous U.S., the change in mean streamflow volume under the biofuel scenario is estimated to range from negative 56% to positive 20% relative to a business-as-usual baseline scenario. In Kansas and Oklahoma, annual streamflow volume is reduced by an average of 20%, and this reduction in streamflow volume is due primarily to increased PET. Predicted increase in mean annual P under the biofuel crop production scenario is lower than its inter-annual variability, indicating that additional simulations would be necessary to determine conclusively whether predicted change in P is a response to biofuel crop production. Although estimated changes in streamflow volume include the influence of P change, sensitivity results show that PET change is the significantly dominant factor causing streamflow change. Higher PET and lower streamflow due to biofuel feedstock production are likely to increase water stress in the High Plains. When pursuing sustainable biofuels policy, decision-makers should consider the impacts of feedstock production on water scarcity. 相似文献
883.
Saud N. Al Sifri Wael Almahmeed Sami Azar Osama Okkeh Peter Bramlage Claus Jünger Islam Halawa Baishali Ambegaonkar Sameh Wajih Philippe Brudi 《PloS one》2014,9(1)
Background
Therapeutic intervention with low-density lipoprotein cholesterol-lowering agents known as statins has been demonstrated to reduce cardiovascular risk. However, many patients on statin treatment have persistent dyslipidemia and remain at a high risk of cardiovascular disease. Therefore, the objective of this study was to assess the frequency of lipid abnormalities in patients receiving chronic statin treatment.Methods
As part of an international, cross-sectional, observational study, DYSIS-Middle East enrolled 2,182 patients in the United Arab Emirates (UAE), Saudi Arabia, Lebanon and Jordan. All patients were over 45 years of age and had been on statin treatment for at least three months. Data on demographics, lipid parameters and cardiovascular risk profile were recorded. Cardiovascular risk was defined according the guidelines of the European Society of Cardiology.Results
The majority of patients (82.6%) were classified as being at very high risk of cardiovascular events, and 61.8% of all patients did not attain LDL-C target levels. Low high-density lipoprotein cholesterol levels and elevated triglyceride levels were noted in 55.5% and 48.5% of patients, respectively. Multivariate logistical regression modeling indicated that factors independently associated with LDL-C levels not being at goal were lifestyle choices, diabetes mellitus, ischemic heart disease, and blood pressure ≥ 140/90 mmHg.Conclusions
Almost two-thirds of statin-treated patients in the United Arab Emirates, Saudi Arabia, Lebanon and Jordan had inadequately controlled lipid levels. More comprehensive surveillance, awareness and treatment regimens, as well as modification of lifestyle choices, is necessary to halt the rise in cardiovascular disease-related mortality. 相似文献884.
Here we report the characterization of an octopamine/tyramine (OA/TA or TyrR1) receptor (OA/TAMac) cloned from the freshwater prawn, Macrobrachium rosenbergii, an animal used in the study of agonistic social behavior. The invertebrate OA/TA receptors are seven trans-membrane domain G-protein coupled receptors that are related to vertebrate adrenergic receptors. Behavioral studies in arthropods indicate that octopaminergic signaling systems modulate fight or flight behaviors with octopamine and/or tyramine functioning in a similar way to the adrenalins in vertebrate systems. Despite the importance of octopamine signaling in behavioral studies of decapod crustaceans there are no functional data available for any of their octopamine or tyramine receptors. We expressed OA/TAMac in Xenopus oocytes where agonist-evoked trans-membrane currents were used as readouts of receptor activity. The currents were most effectively evoked by tyramine but were also evoked by octopamine and dopamine. They were effectively blocked by yohimbine. The electrophysiological approach we used enabled the continuous observation of complex dynamics over time. Using voltage steps, we were able to simultaneously resolve two types of endogenous currents that are affected over different time scales. At higher concentrations we observe that octopamine and tyramine can produce different and opposing effects on both of these currents, presumably through the activity of the single expressed receptor type. The pharmacological profile and apparent functional-selectivity are consistent with properties first observed in the OA/TA receptor from the insect Drosophila melanogaster. As the first functional data reported for any crustacean OA/TA receptor, these results suggest that functional-selectivity between tyramine and octopamine is a feature of this receptor type that may be conserved among arthropods. 相似文献
885.
Uday Jadhav Jagdish Hiremath Deepak J. Namjoshi Vinod K. Gujral Kamlakar K. Tripathi Mohammad Siraj Paramesh Shamanna Michel Safar 《PloS one》2014,9(4)
Objective
Despite antihypertensive treatment, most hypertensive patients still have high blood pressure (BP), notably high systolic blood pressure (SBP). The EFFICIENT study examines the efficacy and acceptability of a single-pill combination of sustained-release (SR) indapamide, a thiazide-like diuretic, and amlodipine, a calcium channel blocker (CCB), in the management of hypertension.Methods
Patients who were previously uncontrolled on CCB monotherapy (BP≥140/90 mm Hg) or were previously untreated with grade 2 or 3 essential hypertension (BP≥160/100 mm Hg) received a single-pill combination tablet containing indapamide SR 1.5 mg and amlodipine 5 mg daily for 45 days, in this multicenter prospective phase 4 study. The primary outcome was mean change in BP from baseline; percentage of patients achieving BP control (BP<140/90 mm Hg) was a secondary endpoint. SBP reduction (ΔSBP) versus diastolic BP reduction (ΔDBP) was evaluated (ΔSBP/ΔDBP) from baseline to day 45. Safety and tolerability were also assessed.Results
Mean baseline BP of 196 patients (mean age 52.3 years) was 160.2/97.9 mm Hg. After 45 days, mean SBP decreased by 28.5 mm Hg (95% CI, 26.4 to 30.6), while diastolic BP decreased by 15.6 mm Hg (95% CI, 14.5 to 16.7). BP control (<140/90 mm Hg) was achieved in 85% patients. ΔSBP/ΔDBP was 1.82 in the overall population. Few patients (n = 3 [2%]) reported side effects, and most (n = 194 [99%]) adhered to treatment.Conclusion
In patients who were previously uncontrolled on CCB monotherapy or untreated with grade 2 or 3 hypertension, single-pill combination indapamide SR/amlodipine reduced BP effectively—especially SBP— over 45 days, and was safe and well tolerated.Trial Registration
Clinical Trial Registry – India CTRI/2010/091/000114 相似文献886.
887.
Einat Karpestam Sami Merilaita Anders Forsman 《Biological journal of the Linnean Society. Linnean Society of London》2014,112(3):546-555
Polymorphism, the coexistence of two or more variants within a population, has served as a classic model system to address questions about the evolution and maintenance of intraspecific variation. It has been hypothesized that a natural level of colour polymorphism may impair the search efficiency of visually orientated predators. To test this polymorphism protects hypothesis, we asked human participants to search for images of natural black, striped or grey Tetrix subulata grasshopper colour morphs presented against photographs of their natural habitat on computer screens. Fewer grasshoppers were detected when morphs were presented in mixed than in uniform sequences. All three morphs benefited to comparable degrees, in terms of reduced detection, from being presented in polymorphic sequences. Our findings demonstrate that natural levels of polymorphic variation can impede the efficiency of visually orientated predators and increase survival of prey. This protective effect supports the limited attention hypothesis, explains why predators develop ‘search images’, may account for the spread and establishment of novel colour variants, and contributes to maintenance of polymorphisms. © 2014 The Authors. Biological Journal of the Linnean Society published by John Wiley & Sons Ltd on behalf of The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 112 , 546–555. 相似文献
888.
A proteomic approach reveals new actors of nodule response to drought in split‐root grown pea plants
Sami Irar Esther M. González Cesar Arrese‐Igor Daniel Marino 《Physiologia plantarum》2014,152(4):634-645
Drought is considered the more harmful abiotic stress resulting in crops yield loss. Legumes in symbiosis with rhizobia are able to fix atmospheric nitrogen. Biological nitrogen fixation (SNF) is a very sensitive process to drought and limits legumes agricultural productivity. Several factors are known to regulate SNF including oxygen availability to bacteroids, carbon and nitrogen metabolisms; but the signaling pathways leading to SNF inhibition are largely unknown. In this work, we have performed a proteomic approach of pea plants grown in split‐root system where one half of the root was well‐irrigated and the other was subjected to drought. Water stress locally provoked nodule water potential decrease that led to SNF local inhibition. The proteomic approach revealed 11 and 7 nodule proteins regulated by drought encoded by Pisum sativum and Rhizobium leguminosarum genomes respectively. Among these 18 proteins, 3 proteins related to flavonoid metabolism, 2 to sulfur metabolism and 3 RNA‐binding proteins were identified. These proteins could be molecular targets for future studies focused on the improvement of legumes tolerance to drought. Moreover, this work also provides new hints for the deciphering of SNF regulation machinery in nodules. 相似文献
889.
The studies reported in this work are aimed to elucidate the ternary inclusion complex formation of gemfibrozil (GFZ), a poorly
water-soluble drug, with β-cyclodextrin (β-CD) with the aid of auxiliary substances like different grades of povidone(s) (viz.
PVP K-29/32, PVP K-40, Plasdone S-630, and Polyplasdone XL), organic base (viz. triethanolamine), and metal ion (viz. MgCl2·6H2O), by investigating their interactions in solution and solid state. Phase solubility studies were carried out to evaluate
the solubilizing power of β-cyclodextrin, in association with various auxiliary substances, to determine the apparent stability
constant (K
C) and complexation efficiency (CE) of complexes. Improvement in K
C values for ternary complexes clearly proves the benefit of the addition of auxiliary substances to promote CE. Of all the
approaches used, the use of polymer Plasdone S-630 was found to be the most promising approach in terms of optimum CE and
K
C. GFZ–β-CD (1:1) binary and ternary systems were prepared by kneading and lyophilization methods. The ternary systems clearly
signified superiority over binary systems in terms of CE, solubility, K
C, and reduction in the formulation bulk. Optimized ternary system of GFZ–β-CD–Plasdone S-630 prepared by using lyophilization
method indicated a significant improvement in intrinsic dissolution rate when compared with ternary kneaded system. Differential
scanning calorimetry, X-ray diffraction, Fourier transform infrared, scanning electron microscopy, and proton nuclear magnetic
resonance were carried out to characterize the binary and optimized ternary complex. The results suggested the formation of
new solid phases, eliciting strong evidences of ternary inclusion complex formation between GFZ, β-CD, and Plasdone S-630,
particularly for lyophilized products. 相似文献
890.
Prafulla Dutta Siraj Ahmed Khan Dibya Ranjan Bhattarcharyya Abdul Mabood Khan Chandra Kanta Sharma Jagdish Mahanta 《EcoHealth》2010,7(4):498-506
Entomological survey was conducted to know the breeding habitat preference of the forest breeder malaria vector Anopheles baimaii, known earlier as An. dirus species D in the northeastern region of India. Breeding potential of the vector in forest areas was found to be high in water stored in jungle pool (69.84%) followed by elephant footprints with clear water (39.13%) and with turbid water (26.19%), whereas in forest fringe areas, the vector breeding was more prominent in elephant footprints: 65.11% in clear water and 62.5% in turbid water. Although other habitats had shown only low breeding of the vector, all types of habitats were positively correlated with malaria occurrence. Cattle hoof marks (r = 0.998) and elephant footprint (turbid; r = 0.999) explained nearly the same amount of variance. It was observed that deforestation as well as elephant habitat-type destruction had engendered man–elephant conflicts intensively in fringe areas. Seasonal abundance pattern of this vector was found to vary in forest and forest fringe areas in relation to different habitats. Seasonal abundance of An. baimaii was significantly different in different habitats. The Tukey post hoc comparisons indicated that the abundance of An. baimaii in different habitats was significantly higher (P < 0.05) in monsoon season than that of premonsoon and postmonsoon seasons. No significant difference was observed between premonsoon and postmonsoon seasons. The findings therefore will eventually help to predict transmission of malaria in targeted area and in formulating an improved malaria control program in the northeastern region of India. 相似文献