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41.
Considerable clinical and experimental evidence now supports the idea that deficiencies or imbalances in certain highly unsaturated fatty acids may contribute to a range of common developmental disorders including Attention Deficit Hyperactivity Disorder (ADHD). Few intervention studies with LCPUFA supplementation have reported inconsistent and marginal results. This pilot study evaluates the effect of alpha linolenic acid (ALA)-rich nutritional supplementation in the form of flax oil and antioxidant emulsion on blood fatty acids composition and behavior in children with ADHD. Post-supplementation levels of RBC membrane fatty acids were significantly higher than pretreatment levels as well as the levels in control. There was significant improvement in the symptoms of ADHD reflected by reduction in total hyperactivity scores of ADHD children derived from ADHD rating scale.  相似文献   
42.
This short review describes how solid-state NMR has provided a mechanistic and electronic picture of pigment-protein and pigment-pigment interactions in photosynthetic antenna complexes. NMR results on purple bacterial antenna complexes show how the packing of the protein and the pigments inside the light-harvesting oligomers induces mutual conformational stress. The protein scaffold produces deformation and electrostatic polarization of the BChl macrocycles and leads to a partial electronic charge transfer between the BChls and their coordinating histidines, which can tune the light-harvesting function. In chlorosome antennae assemblies, the NMR template structure reveals how the chromophores can direct their self-assembly into higher macrostructures which, in turn, tune the light-harvesting properties of the individual molecules by controlling their disorder, structural deformation, and electronic polarization without the need for a protein scaffold. These results pave the way for addressing the next challenge, which is to resolve the functional conformational dynamics of the lhc antennae of oxygenic species that allows them to switch between light-emitting and light-energy dissipating states.  相似文献   
43.
Currently used anti-tubercular drugs target actively growing Mycobacterium tuberculosis (Mtb) but there are no current therapies targeting persistent mycobacteria. Isocitrate lyase (ICL) is an important enzyme of the glyoxylate shunt pathway used by Mtb for sustaining intracellular infection in inflammatory macrophages under conditions of stress such as nutrient depletion and anaerobic metabolism. Since the humans do not possess this enzyme it constitutes an attractive target for selective drug design. Present work describes synthesis and structural characterization of pyruvate-isoniazid conjugates and their copper complexes with potent anti-tubercular activities against M. tuberculosis H37Rv.  相似文献   
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Cadmium and cadmium compounds are water soluble, mobile in most soils, bio-available, and tend to bio-accumulate. A pot culture experiment was conducted on contaminated soil to study the influence of lime and organic matter on the mobility of cadmium in spinach and its rhizosphere soil. Application of lime (50% and 100% lime requirement) and organic matter (0.5 and 1% by weight of soil) to soil decreased the availability of Cd to the soil and plant throughout the crop growth. The highest diethylene triamine penta-acetic acid (DTPA) extractable Cd was 10.84 mg kg?1 in the treatment OM0 L0 (No application of organic matter and lime) at 20 days after sowing of spinach. Likewise, the highest Cd concentration in spinach roots and shoots were 19.80 and 17.0 mg kg?1 in the treatment OM0 L0 at 20 days after sowing. The Cd concentration in spinach roots and shoots were decreased by 63.23 and 71.88%, respectively, in the treatment OM1 L100 (application of FYM at 1.0% by weight of soil and lime at 100% lime requirement) after 60 days of growth. The lowest concentrations of Cd in the soil and plant after the harvest of the crop were 2.88 and 4.27 mg kg?1, respectively, in the treatment OM1 L100 and resulted in 65.75 and 71.55% decrease over control (OM0 L0). The highest total chlorophyll content of leaves was 2.19 mg kg?1 of fresh weight in the treatment OM1 L100 at 40 days of crop growth.  相似文献   
46.
Pathogens like HIV-1, which evolve into many closely related variants displaying differential infectivity and evolutionary dynamics in a short time scale, require fast and accurate classification. Conventional whole genome sequence alignment-based methods are computationally expensive and involve complex analysis. Alignment-free methodologies are increasingly being used to effectively differentiate genomic variations between viral species. Multifractal analysis, which explores the self-similar nature of genomes, is an alignment-free methodology that has been applied to study such variations. However, whether multifractal analysis can quantify variations between closely related genomes, such as the HIV-1 subtypes, is an open question. Here we address the above by implementing the multifractal analysis on four retroviral genomes (HIV-1, HIV-2, SIVcpz, and HTLV-1), and demonstrate that individual multifractal properties can differentiate between different retrovirus types easily. However, the individual multifractal measures do not resolve within-group variations for different known subtypes of HIV-1 M group. We show here that these known subtypes can instead be classified correctly using a combination of the crucial multifractal measures. This method is simple and computationally fast in comparison to the conventional alignment-based methods for whole genome phylogenetic analysis.  相似文献   
47.
Bupranolol is a promising candidate for transdermal drug delivery system (TDDS) development. The effect of permeation enhancers on the in vivo delivery and beta-blocking effect of reservoir type TDDS was studied in comparison with intravenous BPL in rabbits. The beta-blocking effect was quantified by measuring the inhibition of isoprenaline induced tachycardia in rabbits after BPL administration via transdermal and intravenous routes. The reservoir type TDDS containing a hydroxypropyl cellulose gel and polyethylene membrane was used as a control device. In comparison, the TDDS containing skin penetration enhancers, either 2-pyrrolidone or partially methylated beta cyclodextrin (PMbetaCD) were evaluated. The control device (no enhancer) produced about 52% inhibition of isoprenaline induced tachycardia at 2 h and the effect continued over 24 h application period, however, the devices with 2-pyrolidone or PMbetaCD produced about 85% inhibition of isoprenaline induced tachycardia at 3 h and the same effect continued over 24 h application period. Likewise, the AUC of these devices were significantly higher than that of control device. The intravenous bupranolol showed rapid decline in the pharmacodynamic effect with time indicating its rapid elimination. The in vivo delivery of bupranolol (as estimated by a mass balance study) from the devices made with pyrolidone or PMbetaCD was 3-fold higher than that of control. The results of this study strongly suggest that the penetration enhancers in the TDDS increased the in vivo delivery of BPL, thereby increased the beta-blocking activity of BPL by 50-60% higher than control, enabling the reduction of the TDDS patch size, accordingly.  相似文献   
48.
Daily rhythms are described in almost every variable that can be measured, including suicide rate. The present study aims to find if circadian rhythm exist in suicidal poisoning and completed suicide due to poisoning in central Nepal. The study included all the attempted suicide cases admitted in Patan Hospital and all the completed suicide cases by poisoning reported to Kathmandu District Police during March 2002 to April 2003. The time was grouped into 24 increments of 1 hour. The data were analysed by Kolmogorov-Smirnov test and cosinor analysis. The circadian rhythm of attempted suicide by deliberate self poisoning exhibits a peak at 18:00 h, whereas no circadian rhythm is seen in completed suicides by poisoning although it is bimodal in distribution (6:00-12:00 and 15:00-20:00) with peaks at 7:00 and 18:00 h.  相似文献   
49.
The breast is not a frequent site of filarial infection. We report a case of fine needle aspiration cytologic diagnosis of filariasis of the breast, not previously reported.  相似文献   
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