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1.
This study was conducted to examine the psycho-emotional effects of repeated oral exposure to capsaicin, the principal active component of chili peppers. Each rat received 1 mL of 0.02% capsaicin into its oral cavity daily, and was subjected to behavioural tests following 10 daily administrations of capsaicin. Stereotypy counts and rostral grooming were significantly increased, and caudal grooming decreased, in capsaicin-treated rats during the ambulatory activity test. In elevated plus maze test, not only the time spent in open arms but also the percent arm entry into open arms was reduced in capsaicin-treated rats compared with control rats. In forced swim test, although swimming duration was decreased, struggling increased in the capsaicin group, immobility duration did not differ between the groups. Repeated oral capsaicin did not affect the basal levels of plasma corticosterone; however, the stress-induced elevation of plasma corticosterone was prolonged in capsaicin treated rats. Oral capsaicin exposure significantly increased c-Fos expression not only in the nucleus tractus of solitarius but also in the paraventricular nucleus. Results suggest that repeated oral exposure to capsaicin increases anxiety-like behaviours in rats, and dysfunction of the hypothalamic-pituitary-adrenal axis may play a role in its pathophysiology.  相似文献   
2.

Background:

Vascular growth is a prerequisite for adipose tissue (AT) development and expansion. Some AT cytokines and hormones have effects on vascular development, like vascular endothelial growth factor (VEGF‐A), angiopoietin (ANG‐1), ANG‐2 and angiopoietin‐like protein‐4 (ANGPTL‐4).

Methods:

In this study, the independent and combined effects of diet‐induced weight loss and exercise on AT gene expression and proteins levels of those angiogenic factors were investigated. Seventy‐nine obese males and females were randomized to: 1. Exercise‐only (EXO; 12‐weeks exercise without diet‐restriction), 2. Hypocaloric diet (DIO; 8‐weeks very low energy diet (VLED) + 4‐weeks weight maintenance diet) and 3. Hypocaloric diet and exercise (DEX; 8‐weeks VLED + 4‐weeks weight maintenance diet combined with exercise throughout the 12 weeks). Blood samples and fat biopsies were taken before and after the intervention.

Results:

Weight loss was 3.5 kg in the EXO group and 12.3 kg in the DIO and DEX groups. VEGF‐A protein was non‐significantly reduced in the weight loss groups. ANG‐1 protein levels were significantly reduced 22‐25% after all three interventions (P < 0.01). The ANG‐1/ANG‐2 ratio was also decreased in all three groups (P < 0.05) by 27‐38%. ANGPTL‐4 was increased in the EXO group (15%, P < 0.05) and 9% (P < 0.05) in the DIO group. VEGF‐A, ANG‐1, and ANGPTL‐4 were all expressed in human AT, but only ANGPTL‐4 was influenced by the interventions.

Conclusions:

Our data show that serum VEGF‐A, ANG‐1, ANG‐2, and ANGPTL‐4 levels are influenced by weight changes, indicating the involvement of these factors in the obese state. Moreover, it was found that weight loss generally was associated with a reduced angiogenic activity in the circulation.  相似文献   
3.
Convergence is a significant evolutionary phenomenon. Arrival at similar morphologies from different starting points indicates a strong role for natural selection in shaping morphological phenotypes. There is no evidence yet of convergence in the developmental mechanisms that underlie the evolution of convergent developmental phenotypes. Here we report the expression domains in sea urchins of two important developmental regulatory genes ( Orthodenticle and Runt), and show evidence of molecular convergence in the evolution of direct-developing sea urchins. Indirect development is ancestral in sea urchins. Evolutionary loss of the feeding pluteus stage and precocious formation of the radially symmetric juvenile has evolved independently in numerous sea urchin lineages, thus direct development is an evolutionary convergence. Indirect-developing species do not express Otx during the formation of their five primordial tube feet, the ancestral condition. However, each direct-developing urchin examined does express Otx in the tube feet. Otx expression in the radial arms of direct-developing sea urchins is thus convergent, and may indicate a specific need for Otx use in direct development, a constraint that would make direct development less able to evolve than if there were multiple molecular means for it to evolve. In contrast, Runt is expressed in tube feet in both direct- and indirect-developing species. Because echinoderms are closely related to chordates and postdate the protostome/deuterostome divergence, they must have evolved from bilaterally symmetrical ancestors. Arthropods and chordates use Otx in patterning their anterior axis, and Runt has multiple roles including embryonic patterning in arthropods, and blood and bone cell differentiation in vertebrates. Runt has apparently been co-opted in echinoderms for patterning of pentamery, and Otx in pentameral patterning among direct-developing echinoids. The surprisingly dynamic nature of Otx evolution reinvigorates debate on the role of natural selection vs shared ancestry in the evolution of novel features.  相似文献   
4.

Background  

The present study was designed to examine the effect of chronic treatment with rosiglitazone - thiazolidinedione used in the treatment of type 2 diabetes mellitus for its insulin sensitizing effects - on the Leydig cell steroidogenic capacity and expression of the steroidogenic acute regulatory protein (StAR) and cholesterol side-chain cleavage enzyme (P450scc) in normal adult rats.  相似文献   
5.
Larval dorsoventral (DV) and left-right (LR) axial patterning unfold progressively in sea urchin development, leading to commitment of the major embryonic regions by the gastrula stage. The direct-developing sea urchin Heliocidaris erythrogramma has lost oral-aboral differentiation along the DV axis but has accelerated vestibular ectoderm development on the left side. NiCl(2) radializes indirect-developing sea urchins by shifting cells toward a ventral fate (oral ectoderm). We treated embryos of H. erythrogramma and the indirect-developing H. tuberculata with NiCl(2). H. tuberculata was ventralized exactly like other indirect developers, establishing that basic patterning mechanisms are conserved in this genus. H. erythrogramma was also radialized; timing, dosage response, and some morphological features were similar to those in other sea urchins. Ectodermal explant and recombination experiments demonstrate that the effect of nickel is autonomous to the ectoderm, another feature in common with indirect developers. However, H. erythrogramma is distinctly sinistralized rather than ventralized, its cells shifting toward a left-side fate (vestibular ectoderm). This geometric contrast in the midst of pervasive functional similarity suggests that nickel-sensitive processes in H. erythrogramma axial patterning, homologous to those in indirect developers, have been redeployed, and hence co-opted, from their ancestral role in DV axis determination to a new role in LR axis determination. We discuss DV and LR axial patterning and their evolutionary transformation.  相似文献   
6.

Background  

Topic detection is a task that automatically identifies topics (e.g., "biochemistry" and "protein structure") in scientific articles based on information content. Topic detection will benefit many other natural language processing tasks including information retrieval, text summarization and question answering; and is a necessary step towards the building of an information system that provides an efficient way for biologists to seek information from an ocean of literature.  相似文献   
7.
Kong M  Kim M  Ryu S 《Journal of virology》2012,86(11):6379-6380
Bacillus cereus is a ubiquitous, spore-forming bacterium associated with food poisoning cases. To develop an efficient biocontrol agent against B. cereus, we isolated lytic phage PBC1 and sequenced its genome. PBC1 showed a very low degree of homology to previously reported phages, implying that it is novel. Here we report the complete genome sequence of PBC1 and describe major findings from our analysis.  相似文献   
8.
9.

Background  

Several forms of progressive retinal atrophy (PRA) segregate in more than 100 breeds of dog with each PRA segregating in one or a few breeds. This breed specificity may be accounted for by founder effects and genetic drift, which have reduced the genetic heterogeneity of each breed, thereby facilitating the identification of causal mutations. We report here a new form of PRA segregating in the Border Collie breed. The clinical signs, including the loss of night vision and a progressive loss of day vision, resulting in complete blindness, occur at the age of three to four years and may be detected earlier through systematic ocular fundus examination and electroretinography (ERG).  相似文献   
10.
三氧化二砷对食管癌细胞增殖和热休克蛋白70表达的影响   总被引:2,自引:0,他引:2  
目的:研究三氧化二砷(As2O3)对食管癌细胞增殖和热休克蛋白70(HSP70)表达的影响。方法:通过相差显微镜、流式细胞术、免疫细胞化学染色和免疫印迹分析等方法观察As2O3对人食管癌细胞株EC1的作用效果和作用机制。结果:与对照组相比,经2μmol/L和5μmol/Las2O3作用的细胞出现明显的生长抑制,G2/M期细胞比例增加;2μmol/Las2O3作用48h后经Ecl细胞HSP70(heat shock protein70)及HSC70(heat shock cognate protein70)表达均增加。结论:As2O3诱导食管癌细胞G2/M期阻滞抑制细胞增殖和生长;HSP70的升高是细胞对As2O3作用后出现的应激反应,并与细胞周期阻滞相关。  相似文献   
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