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1.
Little is known about the effect of exercise training on the expression of adiponectin receptor genes in peripheral blood mononuclear cells (PBMCs). In this study, we investigated the effects of aerobic training on the expression of AdipoR1 and AidpoR2 mRNAs in PBMCs, whole body insulin sensitivity, and circulating adiponectins in men. Thirty young men were randomly assigned to either a control (n=15) or an exercise (n=15) group. Subjects assigned to the exercise group underwent a 12-week jogging and/or running programme on a motor-driven treadmill at an intensity of 60%-75% of the age-based maximum heart rate with duration of 40 minutes per session and a frequency of 5 days per week. Two-way mixed ANOVA with repeated measures was used to test any significant time-by-group interaction effects for the measured variables at p=0.05. We found significant time-by-group interaction effects for waist circumference (p=0.001), VO2max (p<0.001), fasting insulin (p=0.016), homeostasis model assessment for insulin resistance (HOMA-IR) (p=0.010), area under the curve (AUC) for insulin response during the 75-g oral glucose tolerance test (p=0.002), high-molecular weight (HMW) adiponectin (p=0.016), and the PBMC mRNA levels of AdipoR1 (p<0.001) and AdipoR2 (p=0.001). The exercise group had significantly increased mRNA levels of AdipoR1 and AdipoR2 in PBMCs, along with increased whole body insulin sensitivity and HMW adiponectin, decreased waist circumference, and increased VO2max compared with the control group. In summary, the current findings suggest that exercise training modulates the expression of AdipoR1 and AdipoR2 mRNAs in PBMCs, implying that manipulation of the expression of these genes could be a potential surrogate for lifestyle intervention-mediated improvements of whole body insulin sensitivity and glucose homeostasis.  相似文献   
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Although Uncinaria stenocephala is the most frequent hookworm in the intestine of dogs from Northern, Central and Southern Europe, little is known about its host-parasite relationship. Three groups of sera from dogs (Group 1: dogs naturally infected only by U. stenocephala; Group 2: helminth-free dogs at necropsy, and Group 3: dogs parasitized by other helminths) were analyzed by ELISA using U. stenocephala antigens from adult worms (somatic and excretory-secretory antigens) and from L3 larvae (somatic antigens). All three sources of antigens were found to be suitable for immunodiagnosis of canine uncinariosis with up to 90% efficacy. However, an analysis to assess the diagnostic value of the different antigens demonstrated that the adult excretory-secretory antigens had a higher diagnostic efficacy (96.7%), indicating that this is the best antigen source for the diagnosis of Uncinaria infection.  相似文献   
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The chemical nature of the sensitizer and its selective uptake by malignant cells are decisive to choose an appropriate biocompatible carrier, able to preserve the photosensitizing characteristics of the dye. In this paper we demonstrate the photodynamic properties of three chlorins, derived from chlorophyll a, and the usefulness of liposomal carriers to design pharmaceutical formulations. The chlorins have been quantitatively incorporated into stable liposomes obtained from a mixture of l-α-palmitoyloleoylphosphatidylcholine and l-α-dioleoylphosphatidylserine in a 13.5:1.5 molar ratio (POPC/OOPS-liposomes). The chlorin uptake by skin fibroblasts increases steadily, reaching in all cases a plateau level dependent on both the chlorin structure and the vehicle employed. The photophysical properties of the three chlorins in THF are nearly identical and fulfill the requirements for a PDT photosensitizer. Incorporation of chlorins into liposomes induces important changes in their photophysics, but does not impair their cellular uptake or their cell photosensitization ability. In fact we observe in the cells the same photophysical behavior as in THF solution. Specifically, we demonstrate, by recording the near-IR phosphorescence of 1O2, that the chlorins are able to photosensitize the production of 1O2 in the cell membrane. The cell-photosensitization efficiency depended on the chlorin and cell line nature, the carrier, and the length of pre-incubation and post-irradiation periods. The high photodynamic activity of chlorin-loaded liposomes and the possibility to design liposomal carriers to achieve a specific target site favors this approach to obtain an eventual pharmaceutical formulation.  相似文献   
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Background

Many studies have provided evidence of the existence of genetic heterogeneity of environmental variance, suggesting that it could be exploited to improve robustness and uniformity of livestock by selection. However, little is known about the perspectives of such a selection strategy in beef cattle.

Methods

A two-step approach was applied to study the genetic heterogeneity of residual variance of weight gain from birth to weaning and long-yearling weight in a Nellore beef cattle population. First, an animal model was fitted to the data and second, the influence of additive and environmental effects on the residual variance of these traits was investigated with different models, in which the log squared estimated residuals for each phenotypic record were analyzed using the restricted maximum likelihood method. Monte Carlo simulation was performed to assess the reliability of variance component estimates from the second step and the accuracy of estimated breeding values for residual variation.

Results

The results suggest that both genetic and environmental factors have an effect on the residual variance of weight gain from birth to weaning and long-yearling in Nellore beef cattle and that uniformity of these traits could be improved by selecting for lower residual variance, when considering a large amount of information to predict genetic merit for this criterion. Simulations suggested that using the two-step approach would lead to biased estimates of variance components, such that more adequate methods are needed to study the genetic heterogeneity of residual variance in beef cattle.  相似文献   
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Golgi antiapoptotic protein (GAAP) is a novel regulator of cell death that is highly conserved in eukaryotes and present in some poxviruses, but its molecular mechanism is unknown. Given that alterations in intracellular Ca2+ homeostasis play an important role in determining cell sensitivity to apoptosis, we investigated if GAAP affected Ca2+ signaling. Overexpression of human (h)-GAAP suppressed staurosporine-induced, capacitative Ca2+ influx from the extracellular space. In addition, it reduced histamine-induced Ca2+ release from intracellular stores through inositol trisphosphate receptors. h-GAAP not only decreased the magnitude of the histamine-induced Ca2+ fluxes from stores to cytosol and mitochondrial matrices, but it also reduced the induction and frequency of oscillatory changes in cytosolic Ca2+. Overexpression of h-GAAP lowered the Ca2+ content of the intracellular stores and decreased the efficacy of IP3, providing possible explanations for the observed results. Opposite effects were obtained when h-GAAP was knocked down by siRNA. Thus, our data demonstrate that h-GAAP modulates intracellular Ca2+ fluxes induced by both physiological and apoptotic stimuli.  相似文献   
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Aim  The aim of this work was to identify the main changes in the flora and vegetation of the Iberian Peninsula over the Cenozoic Era, to record the disappearance of taxa associated with these changes and to determine the influence of climate and human activity on these events.
Location  The Iberian Peninsula and Balearic Islands.
Methods  A critical review was made of the palaeobotanical literature with the aims of detecting patterns of floristic change and extracting information on the disappearance of different taxa over the Cenozoic. These data are viewed alongside the most recent data for the climate of this period. A critical analysis is made of the role of Palaeotropical and Arctotertiary taxa in the forest communities of the Iberian Peninsula throughout the Cenozoic.
Results  Although the Eocene–Oligocene transition was a time when many taxa disappeared, the most outstanding events occurred between the end of the Oligocene and throughout the Miocene. Substantial floristic changes took place over this period, including the disappearance of 177 Palaeotropical taxa. This was probably related to acute cooling and aridification; no evidence exists that the Messinian Salinity Crisis had any important effect in the Iberian Peninsula. The last great disappearance of Palaeotropical taxa (36 in total) ended in the Middle–Late Piacenzian; Arctotertiary taxa were most affected during the Pleistocene. The Lower–Middle Pleistocene transition, best represented by marine isotopic stages (MIS) 36–34 and 20–18 and characterized by a change in glacial cyclicity, was the time of the last notable disappearance of taxa.
Main conclusions  This work provides the first chronogram of extinctions for the Iberian flora, and records the disappearance of 277 taxa during the Cenozoic. A clear relationship was detected between the main climatic events and the latest appearances of the different taxa.  相似文献   
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