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161.
JB Farinha DL Dos Santos G Bresciani LF Bard F de Mello ST Stefanello AA Courtes FAA Soares 《Biology of sport / Institute of Sport》2015,32(2):109-114
The aim of this study was to investigate the impact of moderate aerobic training on functional, anthropometric, biochemical, and health-related quality of life (HRQOL) parameters on women with metabolic syndrome (MS). Fifteen untrained women with MS performed moderate aerobic training for 15 weeks, without modifications of dietary behaviours. Functional, anthropometric, biochemical, control diet record and HRQOL parameters were assessed before and after the training. Despite body weight maintenance, the patients presented decreases in waist circumference (P = 0.001), number of MS components (P = 0.014), total cholesterol (P = 0.049), HDL cholesterol (P = 0.004), LDL cholesterol (P = 0.027), myeloperoxidase activity (P = 0.002) and thiobarbituric acid-reactive substances levels (P = 0.006). There were no differences in total energy, carbohydrate, protein and lipid intake pre- and post-training. Furthermore, improvements in the HRQOL subscales of physical functioning (P = 0.03), role-physical (P = 0.039), bodily pain (P = 0.048), general health (P = 0.046) and social functioning scoring (P = 0.011) were reported. Despite the absence of weight loss, aerobic training induced beneficial effects on functional, anthropometric, biochemical and HRQOL parameters in women with MS. 相似文献
162.
Estimation of the membrane potential of cultured macrophages from the fast potential transient upon microelectrode entry 总被引:3,自引:1,他引:2 下载免费PDF全文
Analysis of membrane potential recordings upon microelectrode impalement of four types of macrophages (cell lines P388D1 and PU5-1.8, cultured mouse peritoneal macrophages, and cultured human monocytes) reveals that these cells have membrane potentials at least two times more negative than sustained potential values (E(s)) frequently reported. Upon microelectrode entry into the cell (P388D1), the recorded potential drops to a peak value (E(p)) (mean -37 mV for 50 cells, range -15 to -70 mV) within 2 ms, after which it decays to a depolarized potential (E(n)) (mean -12 mV) in about 20 ms. Thereafter, the membrane develops one or a series of slow hyperpolarizations before a final sustained membrane potential (E(s)) (mean -14 mV, range -5 to -40) is established. The mean value of the peak of the first hyperpolarization (E(h)) is -30 mV (range -10 to -55 mV). The initial fast peak transient, measured upon microelectrode entry, was first described and analyzed by Lassen et al. (Lassen, U.V., A.M. T. Nielson, L. Pape, and L. O. Simonsen, 1971, J. Membr. Biol. 6:269-288 for other change in the membrane potential from its real value before impalement to a sustained depolarized value. This was shown to be true for macrophages by two-electrode impalements of single cells. Values of E(p), E(n), E(h), E(s), and membrane resistance (R(m)) measured for the other macrophages were similar to those of P388D1. From these results we conclude that E(p) is a better estimate of the true membrane potential of macrophages than E(s), and that the slow hyperpolarizations upon impalement should be regarded as transient repolarizations back to the original membrane potentials. Thus, analysis of the initial fast impalement transient can be a valuable aid in the estimation of the membrane potential of various sorts of small isolated cells by microelectrodes. 相似文献
163.
164.
Sze SH; Roytberg MA; Gelfand MS; Mironov AA; Astakhova TV; Pevzner PA 《Bioinformatics (Oxford, England)》1998,14(1):14-19
MOTIVATION: Gene annotation is the final goal of gene prediction
algorithms. However, these algorithms frequently make mistakes and
therefore the use of gene predictions for sequence annotation is hardly
possible. As a result, biologists are forced to conduct time-consuming gene
identification experiments by designing appropriate PCR primers to test
cDNA libraries or applying RT-PCR, exon trapping/amplification, or other
techniques. This process frequently amounts to 'guessing' PCR primers on
top of unreliable gene predictions and frequently leads to wasting of
experimental efforts. RESULTS: The present paper proposes a simple and
reliable algorithm for experimental gene identification which bypasses the
unreliable gene prediction step. Studies of the performance of the
algorithm on a sample of human genes indicate that an experimental protocol
based on the algorithm's predictions achieves an accurate gene
identification with relatively few PCR primers. Predictions of PCR primers
may be used for exon amplification in preliminary mutation analysis during
an attempt to identify a gene responsible for a disease. We propose a
simple approach to find a short region from a genomic sequence that with
high probability overlaps with some exon of the gene. The algorithm is
enhanced to find one or more segments that are probably contained in the
translated region of the gene and can be used as PCR primers to select
appropriate clones in cDNA libraries by selective amplification. The
algorithm is further extended to locate a set of PCR primers that uniformly
cover all translated regions and can be used for RT-PCR and further
sequencing of (unknown) mRNA.
相似文献
165.
The clock gene period (per) controls a number of biological rhythms in
Drosophila. In D. melanogaster, per has a repetitive region that encodes a
number of alternating threonine-glycine residues. We sequenced and compared
this region from several different Drosophila species belonging to various
groups within the Drosophila and Sophophora subgenera. This part of per
shows a great variability in both DNA sequence and length. Furthermore,
analysis of the data suggests that changes in the length of this variable
region might be associated with amino acid replacements in the more
conserved flanking sequences.
相似文献
166.
Seeds of alfalfa (Medicago sativa L.) can exhibit seedcoat imposed dormancy, which produces hard seeds within a seed lot. These seeds do not germinate because they do not imbibe water due to a barrier to water entry in the seed coat. The aim of this work was to analyze the anatomical and chemical characteristics of the testa of alfalfa seeds with respect to water permeability levels. The anatomy of seeds of the cv. Baralfa 85 was studied and structural substances, polyphenols, tannins and cutin present in the testa of seeds of different water permeability levels were determined. The anatomical characteristics of the seed coat and the proportions of components were found to determine the permeability level of the seed coat, an aspect that is associated with the physical seed dormancy level. Anatomically, increased thickness of the testa was associated with a lower permeability level. The difference may be attributed to the variation in cuticle thickness, length of macrosclereids and thickness of the cell wall, and presence and development of osteosclereids. From the physiological and chemical points of view, the mechanism of physical dormancy of the testa is explained by a greater amount of components that repel water and cement the cell wall, such as polyphenols, lignins, condensed tannins, pectic substances, and a lower proportion of cellulose and hemicellulose. 相似文献
167.
Background
Quantifying the amount of standing genetic variation in fitness represents an empirical challenge. Unfortunately, the shortage of detailed studies of the genetic architecture of fitness has hampered progress in several domains of evolutionary biology. One such area is the study of sexual selection. In particular, the evolution of adaptive female choice by indirect genetic benefits relies on the presence of genetic variation for fitness. Female choice by genetic benefits fall broadly into good genes (additive) models and compatibility (non-additive) models where the strength of selection is dictated by the genetic architecture of fitness. To characterize the genetic architecture of fitness, we employed a quantitative genetic design (the diallel cross) in a population of the seed beetle Callosobruchus maculatus, which is known to exhibit post-copulatory female choice. From reciprocal crosses of inbred lines, we assayed egg production, egg-to-adult survival, and lifetime offspring production of the outbred F1 daughters (F1 productivity). 相似文献168.
Hekmat A Saboury AA Moosavi-Movahedi AA Ghourchian H Ahmad F 《Acta biochimica Polonica》2008,55(3):549-557
A reversible effect of pH on the ionization of amino-acid residues at the active center of choline oxidase was observed near the optimum pH (8). Inactivation of choline oxidase took place in the pH ranges 3-6 and 9-11, in which irreversible changes in the structure occur leading to the enzyme inactivation. The first order rate constants of the enzyme's inactivation at various pH values were estimated for the irreversible changes. The Arrhenius analysis revealed no significant changes in the activation enthalpy, while an increase in the activation entropy reflected an increase in the conformational freedom. 相似文献
169.
Ajloo D Taghizadeh E Saboury AA Bazyari E Mahnam K 《International journal of biological macromolecules》2008,43(2):151-158
Effects of sodium dodecyl sulfate, dodecyltrimethylammonium bromide, sodium chloride, sodium sulfate, methanol and ethanol, on the structure and activity of adenosine deaminase (ADA) were investigated by UV-Vis, circular dichroism spectrophotometry and molecular dynamics (MDs) studies. Relative activity, experimental and computational helix content, total accessible surface area (ASA) and exposed charged surface area (ECSA) were obtained. The relative activity of ADA in the absence and the presence of denaturants were compared with structural results. It was shown that an increase in the surface area and a decrease in the amount of helicity are associated with a decrease in the activity of ADA. 相似文献
170.