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21.
The purpose of this study was to examine the effects of prolonged basketball skills training on maximal aerobic power, isokinetic strength, joint mobility, and body fat percentage, in young basketball players, and controls of the same age. Twenty basketball players and 18 control boys participated in the study. Basketball players participated both in their school's physical education program and in a children's basketball team training program. Controls participated only in their school's physical education program. All subjects were tested every 6 months (18 months total, 11(1/2), 12, 12(1/2), 13 years old) for VO(2)max, peak torque values of the quadriceps and hamstrings at 180 and 300 degrees x s(-1) and range of motion of the knee and hip joints. Body fat percentage was assessed at the beginning and the end of the experimental period. Results showed that the basketball group had lower heart rate values in all ages and higher VO(2) values in the initial test compared with the control in submaximal intensity. The VO(2)max was altered in both groups on the final test, when compared to the initial test. However, the basketball group had a higher VO(2)max on each of the 6-month follow-up measurements, compared to the control group (p < 0.001). At the end of the 18-month follow-up period no significant differences were observed in isokinetic strength and joint mobility of the lower limbs between the 2 groups. On the contrary, the boys of the trained group had significantly lower percentage body fat values, compared to controls. In conclusion, regular basketball training increased aerobic power and decreased body fat percentage of prepubescent boys, while it did not affect muscle strength and joint mobility of the lower limbs. The major implication suggested by the findings of the present study is that, in order to improve the basic physical components, specific training procedures should be incorporated during the basketball training sessions. It is recommended that all children should be involved in some type of cardiovascular and resistance training program.  相似文献   
22.
Metagenomics is a rapidly emerging field of research for studying microbial communities. To evaluate methods presently used to process metagenomic sequences, we constructed three simulated data sets of varying complexity by combining sequencing reads randomly selected from 113 isolate genomes. These data sets were designed to model real metagenomes in terms of complexity and phylogenetic composition. We assembled sampled reads using three commonly used genome assemblers (Phrap, Arachne and JAZZ), and predicted genes using two popular gene-finding pipelines (fgenesb and CRITICA/GLIMMER). The phylogenetic origins of the assembled contigs were predicted using one sequence similarity-based (blast hit distribution) and two sequence composition-based (PhyloPythia, oligonucleotide frequencies) binning methods. We explored the effects of the simulated community structure and method combinations on the fidelity of each processing step by comparison to the corresponding isolate genomes. The simulated data sets are available online to facilitate standardized benchmarking of tools for metagenomic analysis.  相似文献   
23.

Background

Retinal dystrophies (RD) are a group of hereditary diseases that lead to debilitating visual impairment and are usually transmitted as a Mendelian trait. Pathogenic mutations can occur in any of the 100 or more disease genes identified so far, making molecular diagnosis a rather laborious process. In this work we explored the use of whole exome sequencing (WES) as a tool for identification of RD mutations, with the aim of assessing its applicability in a diagnostic context.

Methodology/Principal Findings

We ascertained 12 Spanish families with seemingly recessive RD. All of the index patients underwent mutational pre-screening by chip-based sequence hybridization and resulted to be negative for known RD mutations. With the exception of one pedigree, to simulate a standard diagnostic scenario we processed by WES only the DNA from the index patient of each family, followed by in silico data analysis. We successfully identified causative mutations in patients from 10 different families, which were later verified by Sanger sequencing and co-segregation analyses. Specifically, we detected pathogenic DNA variants (∼50% novel mutations) in the genes RP1, USH2A, CNGB3, NMNAT1, CHM, and ABCA4, responsible for retinitis pigmentosa, Usher syndrome, achromatopsia, Leber congenital amaurosis, choroideremia, or recessive Stargardt/cone-rod dystrophy cases.

Conclusions/Significance

Despite the absence of genetic information from other family members that could help excluding nonpathogenic DNA variants, we could detect causative mutations in a variety of genes known to represent a wide spectrum of clinical phenotypes in 83% of the patients analyzed. Considering the constant drop in costs for human exome sequencing and the relative simplicity of the analyses made, this technique could represent a valuable tool for molecular diagnostics or genetic research, even in cases for which no genotypes from family members are available.  相似文献   
24.
The uracil permease UraA of Escherichia coli is a structurally known prototype for the ubiquitous Nucleobase‐Ascorbate Transporter (NAT) or Nucleobase‐Cation Symporter‐2 (NCS2) family and represents a well‐defined subgroup of bacterial homologs that remain functionally unstudied. Here, we analyze four of these homologs, including RutG of E. coli which shares 35% identity with UraA and is encoded in the catabolic rut (pyr imidine ut ilization) operon. Using amplified expression in E. coli K‐12, we show that RutG is a high‐affinity permease for uracil, thymine and, at low efficiency, xanthine and recognizes also 5‐fluorouracil and oxypurinol. In contrast, UraA and the homologs from Acinetobacter calcoaceticus and Aeromonas veronii are permeases specific for uracil and 5‐fluorouracil. Molecular docking indicates that thymine is hindered from binding to UraA by a highly conserved Phe residue which is absent in RutG. Site‐directed replacement of this Phe with Ala in the three uracil‐specific homologs allows high‐affinity recognition and/or transport of thymine, emulating the RutG profile. Furthermore, all RutG orthologs from enterobacteria retain an Ala at this position, implying that they can use both uracil and thymine and, possibly, xanthine as substrates and provide the bacterial cell with a range of catabolizable nucleobases.  相似文献   
25.
Rhizobium leguminosarum bv. trifolii strain TA1 is an aerobic, motile, Gram-negative, non-spore-forming rod that is an effective nitrogen fixing microsymbiont on the perennial clovers originating from Europe and the Mediterranean basin. TA1 however is ineffective with many annual and perennial clovers originating from Africa and America. Here we describe the features of R. leguminosarum bv. trifolii strain TA1, together with genome sequence information and annotation. The 8,618,824 bp high-quality-draft genome is arranged in a 6 scaffold of 32 contigs, contains 8,493 protein-coding genes and 83 RNA-only encoding genes, and is one of 20 rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Community Sequencing Program.  相似文献   
26.
27.
Structural changes between [OsIIL3]2+ and [OsIIIL3]3+ (L: 2,2′-bipyridine; 1,10-phenanthroline) and molecular and electronic structures of the OsIII complexes [OsIII(bpy)3]3+ and [OsIII(phen)3]3+ are discussed in this paper. Mid-infrared spectra in the ν(bpy) and ν(phen) ring stretching region for [OsII(bpy)3](PF6)2, [OsIII(bpy)3](PF6)3, [OsII(phen)3](PF6)2, and [OsIII(phen)3](PF6)3 are compared, as are X-ray crystal structures. Absorption spectra in the UV region for [OsIII(bpy)3](PF6)3 and [OsIII(phen)3](PF6)3 are dominated by very intense absorptions (ε = 40 000-50 000 M−1 cm−1) due to bpy and phen intra-ligand π → π transitions. In the visible region, relatively narrow bands with vibronic progressions of ∼1500 cm−1 appear, and have been assigned to bpy or phen-based, spin-orbit coupling enhanced, 1π → 3π electronic transitions. Also present in the visible region are ligand-to-metal charge transfer bands (LMCT) arising from π(bpy) → t2g(OsIII) or π(phen) → t2g(OsIII) transitions. In the near infrared, two broad absorption features appear for oxidized forms [OsIII(bpy)3](PF6)3 and [OsIII(phen)3](PF6)3 arising from dπ-dπ interconfigurational bands characteristic of dπ5OsIII. They are observed at 4580 and 5090 cm−1 for [OsIII(bpy)3](PF6)3 and at 4400 and 4990 cm−1 for [OsIII(phen)3](PF6)3. The bpy and phen infrared vibrational bands shift to higher energy upon oxidation of Os(II) to Os(III). In the cation structure in [OsIII(bpy)3](PF6)3, the OsIII atom resides at a distorted octahedral site, as judged by ∠N-Os-N, which varies from 78.78(22)° to 96.61(22)°. Os-N bond lengths are also in general longer for [OsIII(bpy)3](PF6)3 compared to [OsII(bpy)3](PF6)2 (0.010 Å), and for [OsIII(phen)3](PF6)3 compared to [OsII(phen)3](PF6)2 (0.014 Å). Structural changes in the ligands between oxidation states are discussed as originating from a combination of dπ(OsII) → π (bpy or phen) backbonding and charge redistribution on the ligands as calculated by natural population analysis.  相似文献   
28.

Background

Numerous studies have examined the effect of psychological variables on surgical recovery, but no definite conclusion has been reached yet. We sought to examine whether psychological factors influence early surgical recovery.

Methods

We performed a systematic search in PubMed, Scopus and PsycINFO databases to identify studies examining the association of preoperative psychological variables or interventions with objectively measured, early surgical outcomes.

Results

We identified 16 eligible studies, 15 of which reported a significant association between at least one psychological variable or intervention and an early postoperative outcome. However, most studies also reported psychological factors not influencing surgical recovery and there was significant heterogeneity across the studies. Overall, trait and state anxiety, state anger, active coping, subclinical depression, and intramarital hostility appeared to complicate recovery, while dispositional optimism, religiousness, anger control, low pain expectations, and external locus of control seemed to promote healing. Psychological interventions (guided relaxation, couple support visit, and psychiatric interview) also appeared to favor recovery. Psychological factors unrelated to surgical outcomes included loneliness, perceived social support, anger expression, and trait anger.

Conclusion

Although the heterogeneity of the available evidence precludes any safe conclusions, psychological variables appear to be associated with early surgical recovery; this association could bear important implications for clinical practice. Large clinical trials and further analyses are needed to precisely evaluate the contribution of psychology in surgical recovery.  相似文献   
29.
The transfer of the phosphopantetheine chain from coenzyme A (CoA) to the acyl carrier protein (ACP), a key protein in both fatty acid and polyketide synthesis, is catalyzed by ACP synthase (AcpS). Streptomyces coelicolor AcpS is a doubly promiscuous enzyme capable of activation of ACPs from both fatty acid and polyketide synthesis and catalyzes the transfer of modified CoA substrates. Five crystal structures have been determined, including those of ligand-free AcpS, complexes with CoA and acetyl-CoA, and two of the active site mutants, His110Ala and Asp111Ala. All five structures are trimeric and provide further insight into the mechanism of catalysis, revealing the first detailed structure of a group I active site with the essential magnesium in place. Modeling of ACP binding supported by mutational analysis suggests an explanation for the promiscuity in terms of both ACP partner and modified CoA substrates.  相似文献   
30.
Recently we showed that ABA is at least partly responsible for the induction of the polyamine exodus pathway in Vitis vinifera plants. Both sensitive and tolerant plants employ this pathway to orchestrate stress responses, differing between stress adaptation and programmed cell death. Herein we show that ABA is an upstream signal for the induction of the polyamine catabolic pathway in Vitis vinifera. Thus, amine oxidases are producing H2O2 which signals stomata closure. Moreover, the previously proposed model for the polyamine catabolic pathway is updated and discussed.Key words: plant growth, abscissic acid, polyamines, amine oxidases, signaling, oxidative stress, programmed cell deathWe have shown that tobacco salinity induces an exodus of the polyamine (PA) spermidine (Spd) into the apoplast where it is oxidized by polyamine oxidase (PAO) generating hydrogen peroxide (H2O2). Depending on the size of H2O2, it signals either tolerance-effector genes or the programmed cell death syndrome1 (PCD). PAs are ubiquitous and biologically active molecules. In the recent years remarkable progress has been accomplished regarding the regulation of PAs biosynthesis and catalysis, not only under normal physiological but also under stress conditions.1 The most studied PAs are the diamine Putrescine (Put) and its derivatives the triamine Spd and the tetramine spermine (Spm). They are present in the cells in soluble form (S), or conjugated either to low molecular weight compounds (soluble hydrolyzed form, SH) or to “macro” molecules or cell walls (pellet hydrolyzed form, PH). In higher plants, Put is synthesized either directly from ornithine via ornithine decarboxylase (ODC; EC 4.1.1.17) or indirectly from arginine via arginine decarboxylase (ADC; EC 4.1.1.19). Spd and Spm are synthesized via Spd synthase (EC 2.5.1.16, SPDS) and Spm synthase (EC 2.5.1.22, SPMS), respectively, by sequential addition of aminopropyl groups to Put, catalyzed by S-adenosyl-L-methionine decarboxylase (SAMDC; EC 4.1.1.50).2,3 In plants, PAs are present in the cytoplasm, as well as in cellular organelles.4 Recently it was shown that during stress, they are secreted into the apoplast where they are oxidized by amine oxidases (AOs), such as diamine oxidase for Put (DAO, E.C. 1.4.3.6) and polyamine oxidase (PAO, E.C. 1.4.3.4) for Spd and Spm.1,5,6 Oxidation of PAs generates, amongst other products, H2O21,7,8 which is involved in cell signaling processes coordinated by abscissic acid (ABA),9 but also acts as efficient oxidant and, at high concentration, orchestrates the PCD syndrome.6,10 Two types of PA catabolism by PAO are known in plants: the terminal and the back-conversion pathways. The terminal one takes place in the apoplast, produces except H2O2, 1,3-diaminopropane and an aldehyde depending on the species. On the other hand, the back-conversion pathway is intracellular (cytoplasm and peroxisomes) resulting to the production of H2O2 and the sequential production of Put by Spm via Spd.1,7 Now we have shown that PA exodus also occurs in Vitis vinifera and this phenomenon is at least partially induced by abscissic acid (ABA).11 Thus, exogenous application of ABA results to PA exodus into the apoplast of grapevine. PA is oxidized by an AO resulting to production of H2O2. When the titer of H2O2 is below a threshold, expression of tolerance-effector genes is induced, while when it exceeds this threshold the programmed cell death (PCD) syndrome is induced.  相似文献   
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