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1.
Summary Soybean plants were grown in pots with or without vesicular-arbuscular myocorrhizal (VAM) fungi in three soils of low plant-available P content, different texture and different water-holding capacities. Mineral nutrients, except P, were provided in a complete nutrient solution. The biomass of non-VAM plants was positively and fungal colonization negatively correlated with increasingly coarse soil texture. There was no correlation of soil P with host or endophyte growth. Plant growth enhancement was positively correlated with soil water content at −1.5 MPa. These observations suggest soil water status and the mycorrhizal condition interact in influencing plant growth.  相似文献   
2.
Summary Intracellular ethanol concentrations inSaccharomyces cerevisiae were measured using a high cell density fermentation technique which permits samples to be fixed for analysis in less than two seconds. No accumulation of intracellular ethanol was detected, regardless of the stage of fermentation. The technique eliminates artifacts associated with concentrating the cell sample and provides a reliable means for detecting whether other fermentation products accumulate intracellularly.  相似文献   
3.
Russian Journal of Bioorganic Chemistry - A series of novel hybrids of indole-pyrimidine moieties were synthesized and evaluated for their in vitro anti-cancer, in vitro anti-bacteria and...  相似文献   
4.
Abstract

Electrospray mass spectra for selected modified deoxynucleosides and deoxynucleoside monophosphates have been determined. Protonated molecular ions are abundant in the positive ion spectrum, while (M-H) appears in the negative ion spectrum. However, fragment ion intensities are usually low in both spectra. Conditions which promote collision-induced dissociation within the electrospray source facilitate fragment ion formation, and the intensity of BH2 + and S+ (positive ion spectrum) and (M-BH) and B (negative ion spectrum) are enhanced by increasing the skimmer cone voltage. MH+ was detected with as little as 3 pmol of deoxynucleoside, and the protonated molecular ion intensity is linear with respect to analyte concentration over two orders of magnitude.  相似文献   
5.
The conservation of hox genes as well as their genomic organization across the phyla suggests that this system of anterior–posterior axis formation arose early during evolution and has come under strong selection pressure. Studies in the split Hox cluster of Drosophila have shown that proper expression of hox genes is dependent on chromatin domain boundaries that prevent inappropriate interactions among different types of cis-regulatory elements. To investigate whether boundary function and their role in regulation of hox genes is conserved in insects with intact Hox clusters, we used an algorithm to locate potential boundary elements in the Hox complex of mosquito, Anopheles gambiae. Several potential boundary elements were identified that could be tested for their functional conservation. Comparative analysis revealed that like Drosophila, the bithorax region in A. gambiae contains an extensive array of boundaries and enhancers organized into domains. We analysed a subset of candidate boundary elements and show that they function as enhancer blockers in Drosophila. The functional conservation of boundary elements from mosquito in fly suggests that regulation of hox genes involving chromatin domain boundaries is an evolutionary conserved mechanism and points to an important role of such elements in key developmentally regulated loci.  相似文献   
6.

Background

Inequalities in progress towards achievement of Millennium Development Goal four (MDG-4) reflect unequal access to child health services.

Objective

To examine the time trends, socio-economic and regional inequalities of under-five mortality rate (U5MR) in Nepal.

Methods

We analyzed the data from complete birth histories of four Nepal Demographic and Health Surveys (NDHS) done in the years 1996, 2001, 2006 and 2011. For each livebirth, we computed survival period from birth until either fifth birthday or the survey date. Using direct methods i.e. by constructing life tables, we calculated yearly U5MRs from 1991 to 2010. Projections were made for the years 2011 to 2015. For each NDHS, U5MRs were calculated according to child''s sex, mother’s education, household wealth index, rural/urban residence, development regions and ecological zones. Inequalities were calculated as rate difference, rate ratio, population attributable risk and hazard ratio.

Results

Yearly U5MR (per 1000 live births) had decreased from 157.3 (95% CIs 178.0-138.9) in 1991 to 43.2 (95% CIs 59.1-31.5) in 2010 i.e. 114.1 reduction in absolute risk. Projected U5MR for the year 2015 was 54.33. U5MRs had decreased in absolute terms in all sub groups but relative inequalities had reduced for gender and rural/urban residence only. Wide inequalities existed by wealth and education and increased between 1996 and 2011. For lowest wealth quintile (as compared to highest quintile) hazard ratio (HR) increased from 1.37 (95% CIs 1.27, 1.49) to 2.54 ( 95% CIs 2.25, 2.86) and for mothers having no education (as compared to higher education) HR increased from 2.55 (95% CIs 1.95, 3.33) to 3.75 (95% CIs 3.17, 4.44). Changes in regional inequities were marginal and irregular.

Conclusions

Nepal is most likely to achieve MDG-4 but eductional and wealth inequalities may widen further. National health policies should address to reduce inequalities in U5MR through ‘inclusive policies''.  相似文献   
7.
In 2010 the identities of thousands of anti-Plasmodium compounds were released publicly to facilitate malaria drug development. Understanding these compounds’ mechanisms of action—i.e., the specific molecular targets by which they kill the parasite—would further facilitate the drug development process. Given that kinases are promising anti-malaria targets, we screened ~14,000 cell-active compounds for activity against five different protein kinases. Collections of cell-active compounds from GlaxoSmithKline (the ~13,000-compound Tres Cantos Antimalarial Set, or TCAMS), St. Jude Children’s Research Hospital (260 compounds), and the Medicines for Malaria Venture (the 400-compound Malaria Box) were screened in biochemical assays of Plasmodium falciparum calcium-dependent protein kinases 1 and 4 (CDPK1 and CDPK4), mitogen-associated protein kinase 2 (MAPK2/MAP2), protein kinase 6 (PK6), and protein kinase 7 (PK7). Novel potent inhibitors (IC50 < 1 μM) were discovered for three of the kinases: CDPK1, CDPK4, and PK6. The PK6 inhibitors are the most potent yet discovered for this enzyme and deserve further scrutiny. Additionally, kinome-wide competition assays revealed a compound that inhibits CDPK4 with few effects on ~150 human kinases, and several related compounds that inhibit CDPK1 and CDPK4 yet have limited cytotoxicity to human (HepG2) cells. Our data suggest that inhibiting multiple Plasmodium kinase targets without harming human cells is challenging but feasible.  相似文献   
8.
Background: Circulating microRNAs (miRNA) are present in body fluids in stable, cell-free form. Likewise, these miRNAs can be identified in various stages of coronary artery disease (CAD) such as inflammation, endothelial dysfunction, proliferation and atherosclerosis among others. miRNA expression levels can be identified.

Aims and objectives: To determine the expression of circulating miRNAs (miR-126, miR-92, miR-33, miR-145 and miR-155) in CAD patients of Indian origin.

Material and methods: miRNA profiling analysis in blood plasma was performed by quantitative real-time-PCR (qRT-PCR) in 60 angiographically verified subjects including 30 CAD patients and 30 age- and gender-matched controls. Association between the expression of all five circulating miRNAs and clinical characteristics of patients with CAD were analysed using Medcalc statistics. The severity of CAD was assessed using SYNTAX score (SS).

Results: Expression of plasma miR-33 increased by 2.9 folds in CAD patients than in control group (p value ≥0.002) also it was found that miR-33 expression levels in mild cases (SS: ≤22) were significantly higher than CAD controls. There was a modest negative correlation between miR-33 and total cholesterol/high density lipoprotein ratio, triglycerides and very low density lipoprotein.

Conclusion: The study reports a significant association between increased levels of plasma miR-33 and CAD. Thus, plasma miR-33 appears to be a promising non-invasive biomarker, but requires further validation in a large cohort.  相似文献   

9.
Global climate change has profound implications on species distributions and ecosystem functioning. In the coastal zone, ecological responses may be driven by various biogeochemical and physical environmental factors. Synergistic interactions can occur when the combined effects of stressors exceed their individual effects. The Red Sea, characterized by strong gradients in temperature, salinity, and nutrients along the latitudinal axis provides a unique opportunity to study ecological responses over a range of these environmental variables. Using multiple linear regression models integrating in situ, satellite and oceanographic data, we investigated the response of coral reef taxa to local stressors and recent climate variability. Taxa and functional groups responded to a combination of climate (temperature, salinity, air‐sea heat fluxes, irradiance, wind speed), fishing pressure and biogeochemical (chlorophyll a and nutrients ‐ phosphate, nitrate, nitrite) factors. The regression model for each species showed interactive effects of climate, fishing pressure and nutrient variables. The nature of the effects (antagonistic or synergistic) was dependent on the species and stressor pair. Variables consistently associated with the highest number of synergistic interactions included heat flux terms, temperature, and wind speed followed by fishing pressure. Hard corals and coralline algae abundance were sensitive to changing environmental conditions where synergistic interactions decreased their percentage cover. These synergistic interactions suggest that the negative effects of fishing pressure and eutrophication may exacerbate the impact of climate change on corals. A high number of interactions were also recorded for algae, however for this group, synergistic interactions increased algal abundance. This study is unique in applying regression analysis to multiple environmental variables simultaneously to understand stressor interactions in the field. The observed responses have important implications for understanding climate change impacts on marine ecosystems and whether managing local stressors, such as nutrient enrichment and fishing activities, may help mitigate global drivers of change.  相似文献   
10.
Monoacylglycerol lipase (MGL) inhibition provides a potential treatment approach to glaucoma through the regulation of ocular 2-arachidonoylglycerol (2-AG) levels and the activation of CB1 receptors. Herein, we report the discovery of new series of carbamates as highly potent and selective MGL inhibitors. The new inhibitors showed potent nanomolar inhibitory activity against recombinant human and purified rat MGL, were selective (>1000-fold) against serine hydrolases FAAH and ABHD6 and lacked any affinity for the cannabinoid receptors CB1 and CB2. Protein-based 1H NMR experiments indicated that inhibitor 2 rapidly formed a covalent adduct with MGL with a residence time of about 6?h. This interconversion process “intrinsic reversibility” was exploited by modifications of the ligand’s size (length and bulkiness) to generate analogs with “tunable’ adduct residence time (τ). Inhibitor 2 was evaluated in a normotensive murine model for assessing intraocular pressure (IOP), which could lead to glaucoma, a major cause of blindness. Inhibitor 2 was found to decrease ocular pressure by ~4.5?mmHg in a sustained manner for at least 12?h after a single ocular application, underscoring the potential for topically-administered MGL inhibitors as a novel therapeutic target for the treatment of glaucoma.  相似文献   
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