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41.
Studies showed that the metabolic unlike the neuroendocrine effects of ghrelin could be abrogated by co-administered unacylated ghrelin. The aim was to investigate the interaction between ghrelin and desacyl ghrelin administered intraperitoneally on food intake and neuronal activity (c-Fos) in the arcuate nucleus in non-fasted rats. Ghrelin (13 μg/kg) significantly increased food intake within the first 30 min post-injection. Desacyl ghrelin at 64 and 127 μg/kg injected simultaneously with ghrelin abolished the stimulatory effect of ghrelin on food intake. Desacyl ghrelin alone at both doses did not alter food intake. Both doses of desacyl ghrelin injected separately in the light phase had no effects on food intake when rats were fasted for 12 h. Ghrelin and desacyl ghrelin (64 μg/kg) injected alone increased the number of Fos positive neurons in the arcuate nucleus compared to vehicle. The effect on neuronal activity induced by ghrelin was significantly reduced when injected simultaneously with desacyl ghrelin. Double labeling revealed that nesfatin-1 immunoreactive neurons in the arcuate nucleus are activated by simultaneous injection of ghrelin and desacyl ghrelin. These results suggest that desacyl ghrelin suppresses ghrelin-induced food intake by curbing ghrelin-induced increased neuronal activity in the arcuate nucleus and recruiting nesfatin-1 immunopositive neurons.  相似文献   
42.

Background  

We present a biological data warehouse called Atlas that locally stores and integrates biological sequences, molecular interactions, homology information, functional annotations of genes, and biological ontologies. The goal of the system is to provide data, as well as a software infrastructure for bioinformatics research and development.  相似文献   
43.
X-ray study of chicken cytosolic aspartate aminotransferase revealed conformational changes in the protein of two kinds: (1) a shift of the small domain adjacent to substrate-binding area due to interaction of the protein with two carboxyl groups of substrate and (2) a change in inclination of the coenzyme plane due to replacement of C = N bond of the coenzyme with Lys-258 by C = N bond with a substrate. An asymmetry in subunit behaviour is observed in both cases: the domain is shifted in one subunit and the coenzyme is rotated in other. Substrate-binding properties of each subunit are strictly dependent on the protein conformation in substrate-binding area.  相似文献   
44.
Helicobacter pylori infection is highly prevalent in Chile (73%). Usually a minority of infected patients develops complications such as ulcers and gastric cancer that have been associated with the presence of virulence factors (cagA, vacA) and host T helper response (Th1/Th2). Our aim was to evaluate the relationship between strain virulence and host immune response, using a multiple regression approach for the development of a model based on data collected from H. pylori infected patients in Chile. We analyzed levels of selected cytokines determined by ELISA (interleukin (IL)-12, IL-10, interferon (IFN)-gamma and IL-4) and the presence of cagA and vacA alleles polymorphisms determined by PCR in antral biopsies of 41 patients referred to endoscopy. By multiple regression analysis we established a correlation between bacterial and host factors using clinical outcome (gastritis and duodenal ulcer) as dependent variables. The selected model was described by: clinical outcome=0.867491 (cagA)+0.0131847 (IL-12/IL-10)+0.0103503 (IFN-gamma/IL-4) and it was able to explain over 90% of clinical outcomes observations (R(2)=96.4). This model considers that clinical outcomes are better explained by the interaction of host immune factors and strain virulence as a complex and interdependent mechanism.  相似文献   
45.
A successful pregnancy requires synchronized adaptation of maternal immune-endocrine mechanisms to the fetus. Here we show that galectin-1 (Gal-1), an immunoregulatory glycan-binding protein, has a pivotal role in conferring fetomaternal tolerance. Consistently with a marked decrease in Gal-1 expression during failing pregnancies, Gal-1-deficient (Lgals1-/-) mice showed higher rates of fetal loss compared to wild-type mice in allogeneic matings, whereas fetal survival was unaffected in syngeneic matings. Treatment with recombinant Gal-1 prevented fetal loss and restored tolerance through multiple mechanisms, including the induction of tolerogenic dendritic cells, which in turn promoted the expansion of interleukin-10 (IL-10)-secreting regulatory T cells in vivo. Accordingly, Gal-1's protective effects were abrogated in mice depleted of regulatory T cells or deficient in IL-10. In addition, we provide evidence for synergy between Gal-1 and progesterone in the maintenance of pregnancy. Thus, Gal-1 is a pivotal regulator of fetomaternal tolerance that has potential therapeutic implications in threatened pregnancies.  相似文献   
46.
ObjectiveFor the treatment of obesity, both conservative and surgical procedures are available. Psychological factors are likely to influence the choice of treatment; however, to date, systematic studies that investigate these factors are few in number. The aim of our study was to analyze whether patients who undergo a surgical treatment differ from those who require a conservative treatment in regard to psychological factors, regardless of their somatic conditions. Furthermore, predictors of treatment choice will be examined.MethodsA total of 244 patients (189 women), with a mean body mass index of 45.1 kg/m2, underwent a weight reduction treatment, with 126 patients undergoing bariatric surgery and 118 patients participating in a conservative, multimodal outpatient weight reduction program. Differences in the results of the psychological questionnaires between conservatively and surgically treated patients were evaluated through the use of t-tests, χ2-tests and an ANCOVA. For the analysis of the predictors, logistic regression models were calculated.ResultsSurgically and conservatively treated obese patients differ in psychological, somatic, and socio-demographic factors. The psychological differences between the groups are independent of obesity-related co-morbidities, such as body mass index (BMI), type 2 diabetes mellitus, hypertension and coronary heart disease. The following psychological and somatic factors equally predict the choice of bariatric surgery: apathy, delegated active coping, a sense of coherence, complaints, type 2 diabetes mellitus, BMI, and age.ConclusionLongitudinal studies are required to assess the predictive value of the psychological factors in regard to the postsurgical weight course to improve the pre-surgical screening and treatment selection process. The pre-surgical identification of psychological predictors should result in a more personalized medicine course and may ensure long term outcomes.  相似文献   
47.

Background

Fatigue can be triggered by previous perceived stress which may lead to impairment of performance and function. The purpose of the study was to investigate the relationship between fatigue and perceived stress.

Method

Health determinants including sociodemographic factors for associations between fatigue and perceived stress in the general population (N = 2,483) are outlined. Fatigue and stress were assessed with the Chalder Fatigue Scale (CFS) and the Perceived Stress Questionnaire (PSQ).

Results

Within the general population, 25.9% of male and 34.5% of female respondents reported moderate fatigue during the last six months; 9.7% of subjects reported substantial fatigue lasting six months or longer. An adjusted regression analysis (R2corr = .28, p < .001) showed that fatigue is highest associated with perceived stress and self-perceived health status. The following factors were correlated with increased rates of fatigue and perceived stress: female gender, divorce/separation, low social class and poor health status.

Conclusion

We conclude that the two conditions overlap most in terms of socio-economic status and self-perceived health status.
  相似文献   
48.
Recently, a new neuropeptide, named nesfatin-1, was discovered. It has been reported that nesfatin-1 inhibits food intake after injection into the third ventricle as well as intraperitoneal (ip) injection. Cholecystokinin (CCK) is well established to play a role in the regulation of food intake. The aim of the study was to examine whether CCK-8S injected ip modulates neuronal activity in nesfatin-1 immunoreactive (ir) neurons localized in the PVN and in the nucleus of the solitary tract (NTS). Additionally, tyrosine hydroxylase-immunoreactivity (TH-ir) in the PVN was determined to assess the distribution of TH-ir fibers in relation to nesfatin-1-ir. Non-fasted male Sprague-Dawley rats received 6 or 10 µg CCK-8S/kg or vehicle solution (0.15 M NaCl; n = 4 all groups) ip. The number of c-Fos-ir neurons was determined in the PVN, arcuate nucleus (ARC), and NTS. Double staining procedure for nesfatin-1 and c-Fos revealed that CCK-8S increased significantly and in a dose-dependent manner the number of c-Fos positive nesfatin-1-ir neurons in the PVN ( 4-fold and 7-fold) and NTS ( 9-fold and 26-fold). Triple staining in the PVN showed a dose-dependent neuronal activation of nesfatin-1 neurons that were colocalized with CRF and oxytocin. Double labeling against nesfatin-1 and TH revealed that nefatin-1-ir neurons were encircled in a network of TH-ir fibers in the PVN. No effect on the number of c-Fos-ir neurons was observed in the ARC. These results suggest that the effects of CCK on the HPA axis and on food intake may, at least in part, be mediated by nesfatin-1-ir neurons in the PVN.  相似文献   
49.
Ohne ZusammenfassungInstitut für Pflanzenbau und Pflanzenzüchtung der Landwirtschaftl. Hochschule Hohenheim.Vortrag, gehalten auf dem Anerkennungskursus des Reichsnährstandes Berlin-Dahlem am 4. Juli 1934.  相似文献   
50.
Our understanding why a woman's immune system does not reject her histoincompatible fetus is still very limited. Distinct insights into the mechanisms involved in pregnancy maintenance may help us to prevent pregnancy complications, e.g., miscarriages or pre-eclampsia. Immune integration and tolerance at the feto-maternal interface appear to be indispensable for successful pregnancy maintenance. Little is known about the cross talk between ICAM-1, expressed on epithelium, endothelium, and APC, and its ligand, LFA-1, at the feto-maternal interface. However, based on the role of ICAM-1/LFA-1 in allograft acceptance or rejection upon transplantation, adhesion molecules are likely to interfere with successful pregnancy outcome. In this study, we tested the hypothesis that ICAM-1/LFA-1 pathways may be involved in pregnancy rejection in murine models. By blocking ICAM-1/LFA-1-mediated intercellular adhesion events, we show that fetal immune acceptance is restored in challenged pregnancies (e.g., upon exposure to sound stress), and adoptive transfer of LFA-1 cells into pregnant mice induces rejection only in abortion-prone mouse models. ICAM-1/LFA-1 cross talk leads to increased recruitment of proinflammatory cells to the implantation site, promotes dendritic cell maturation in the decidua, and subsequently induces additional local Th1 polarization via mature dendritic cells. Furthermore, our observations clearly point out that mechanisms of fetal tolerance, e.g., indoleamine 2,3-dioxygenase expression, presence of CD4+CD25bright regulatory T cells, and synthesis of asymmetric Abs, are ICAM-1/LFA-1 dependent. Hence, our data shed light on a hierarchical network of immune integration at the feto-maternal interface, in which ICAM-1/LFA-1 cross talk is clearly a proximate mediator capable of disrupting successful pregnancy maintenance.  相似文献   
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