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Abstract

This research was aimed to assess the photosynthetic activities of barley (Hordeum valgare L.), clover (Trifolium repens L.), and pearl millet (Pennisetum glaucum (L.) R. Br.) under different saline conditions with two strains of Pseudomonas putida (UW3 and UW4) treatments. An exceptional observation was revealed on barley biomass ratio (288.8%) that irrigated with brackish saline water (10,000?mg/L) with the presence of P. putida UW4 strain. In general, P. putida UW3 strain was significantly increased crops biomass ratio (249.4%, 202.1%, and 212.5%) for barley, pearl millet, and clover, respectively, which were irrigated with 10,000?mg/L brackish saline water. Plant root and shoot systems were significantly increased in their length and weight reflecting the improvement of plants’ photosynthetic activities under salt stress conditions with the presence of P. putida strains. The results from pulse amplitude modulation fluorometry showed that the plants were recovered from the saline stress effect once P. putida strains were applied. The outcome of this research was highly recommended to apply P. putida strains (UW3 and UW4) with field crops for phytoremediation, in particular, where salinity (soil and/or brackish water) was environmentally challenging.  相似文献   
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MethodsThis cross-sectional cohort study was conducted to identify LOMS and YOMS patients’ with relapsing remitting course at MS diagnosis. Time (years) to reach sustained EDSS 6.0 was compared between LOMS and AOMS patients. Cox proportional hazards model was used to evaluate the demographic and clinical predictors of time to EDSS 6.0 in these cohorts.ResultsLOMS and YOMS cohorts comprised 99 (10.7%) and 804 (89.3%) patients respectively. Spinal cord presentation at MS onset was more common among LOMS patients (46.5% vs. 32.3%). The proportions of LOMS and YOMS patients reaching EDSS 6.0 during the follow-up period were 19.2% and 15.7% respectively. In multivariable Cox proportional hazards model, older age at MS onset (adjusted hazard ratio (aHR) = 3.96; 95% CI: 2.14–7.32; p < 0.001), male gender (aHR = 1.85; 95% CI: 1.22–2.81; p = 0.004) and spinal cord presentation at onset (aHR = 1.47; 95% CI: 0.98–2.21; p = 0.062) were significantly associated with shorter time to EDSS 6.0.ConclusionsLOMS patients attained EDSS 6.0 in a significantly shorter period that was influenced by male gender and spinal cord presentation at MS onset.  相似文献   
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Decreased production of vasodilator substances such as nitric oxide (NO) has been proposed as important in development of pulmonary arterial hypertension (PAH). We hypothesize that NO measured over time serves as a non invasive marker of severity of PAH and response to therapy. We prospectively and serially measured exhaled NO and carbon monoxide (CO), a vasodilator and anti-inflammatory product of heme oxygenases, in 17 PAH patients in conjunction with hemodynamic parameters over 2 years. Although pulmonary artery pressures and NO were similar in all patients at entry to the study, NO increased in the 12 individuals who survived to complete the study, and correlated with change in pulmonary artery pressures. In contrast, CO did not change or correlate with hemodynamic parameters. Investigation of NO-oxidant reaction products in PAH in comparison to controls suggests that NO synthesis is impaired in the lung and that reactive oxygen species may be involved in the pathophysiology of pulmonary hypertension. Endogenous NO is inversely related to pulmonary artery pressure in PAH, with successful therapy of PAH associated with increase in NO.  相似文献   
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We are reporting the discovery of small molecule inhibitors for vascular endothelial growth factor receptor type 2 (VEGFR-2) extracellular domain. The VEGFR-2 extracellular domain is responsible for the homo-dimerization process, which has been recently reported as a main step in VEGFR signal transduction cascade. This cascade is essential for the vascularization and survival of most types of cancers. Two main design strategies were used; Molecular docking-based Virtual Screening and Fragment Based Design (FBD). A virtual library of drug like compounds was screened using a cascade of docking techniques in order to discover an inhibitor that binds to this new binding site. Rapid docking methodology was used first to filter the large number of compounds followed by more accurate and slow ones. Fragment based molecular design was adopted afterwards due to unsatisfactory results of screening process. Screening and design process resulted in a group of inhibitors with superior binding energies exceeding that of the natural substrate. Molecular dynamics simulation was used to test the stability of binding of these inhibitors and finally the drug ability of these compounds was assisted using Lipinski rule of five. By this way the designed compounds have shown to possess high pharmacologic potential as novel anticancer agents.  相似文献   
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Background  

The literature is nearly unanimous in recommending elective cesarean delivery at 39 weeks of gestation because of the lower rates of neonatal respiratory complications compared to 38 weeks. However, elective cesarean delivery at 39 weeks or more may have maternal and other fetal consequences compared to delivery at 38 weeks, which are not always addressed in these studies.  相似文献   
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Gene targeting techniques have led to the phenotypic characterization of numerous genes; however, many genes show minimal to no phenotypic consequences when disrupted, despite many having highly conserved sequences. The standard explanation for these findings is functional redundancy. A competing hypothesis is that these genes have important ecological functions in natural environments that are not needed under laboratory settings. Here we discriminate between these hypotheses by competing mice (Mus musculus) whose Hoxb1 gene has been replaced by Hoxa1, its highly conserved paralog, against matched wild-type controls in seminatural enclosures. This Hoxb1A1 swap was reported as a genetic manipulation resulting in no discernible embryonic or physiological phenotype under standard laboratory tests. We observed a transient decline in first litter size for Hoxb1A1 homozygous mice in breeding cages, but their fitness was consistently and more dramatically reduced when competing against controls within seminatural populations. Specifically, males homozygous for the Hoxb1A1 swap acquired 10.6% fewer territories and the frequency of the Hoxb1A1 allele decreased from 0.500 in population founders to 0.419 in their offspring. The decrease in Hoxb1A1 frequency corresponded with a deficiency of both Hoxb1A1 homozygous and heterozygous offspring. These data suggest that Hoxb1 and Hoxa1 are more phenotypically divergent than previously reported and support that sub- and/or neofunctionalization has occurred in these paralogous genes leading to a divergence of gene function and incomplete redundancy. Furthermore, this study highlights the importance of obtaining fitness measures of mutants in ecologically relevant conditions to better understand gene function and evolution.  相似文献   
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