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941.
942.
943.
INTRODUCTION: A large body of evidence suggests that predisposition to suicide, an important public health problem, is mediated to a certain extent by neurobiological factors. The objective of this cross-sectional study was to compare the prevalence of white matter hyperintensities (WMH) in patients with major affective disorders with and without histories of suicide attempts. METHODS: T2-weighted magnetic resonance images (MRI) of 65 psychiatric inpatients with major depressive disorder or bipolar disorder were rated for the presence of WMH. Diagnoses, presence or absence of suicide risk and substance abuse were determined by the Mini International Neuropsychiatric Interview (MINI). Medical charts were reviewed to ascertain history of suicide attempt and basic clinical variables. Fisher's Exact Tests and logistic regression modeling were used to test the association between WMH and suicidality. Suicidal patients and controls were not matched for demographic variables and exposure to some risk factors. RESULTS: Bivariate analysis showed that the prevalence of WMH was significantly higher in subjects with past suicide attempts (Fisher's Exact Test, p = 0.01) and other clinical indicators of elevated suicide risk. Logistic regression analyses controlling for age, sex, and several clinical risk factors supported this finding (odds ratio = 4.7; 95% confidence interval: 1.4, 16.1). CONCLUSIONS: The increased prevalence of WMH in adults with major affective disorders and a history of suicide attempt, compared to similar patients without such a history, is consistent with previous findings in depressed children, youth and young adults. However, the association between WMH and suicidality holds true for both, depressed and bipolar patients. Our results suggest that WMH in patients with major affective disorders might be useful biological markers of suicidality.  相似文献   
944.
Rationale  Preclinical models are needed to investigate the neurobiology and psychobiology of binge eating and to identify innovative pharmacotherapeutic strategies. Objectives  A modification of the model based on the combination of cyclic caloric restrictions and acute stress was developed to further increase its face validity and reliability and, for the first time, to assess its predictive value. Materials and methods  Four groups of female rats were employed: group 1 was normally fed and not stressed on the test day (25th); group 2 was fed normally but was exposed to an acute stress on day 25; group 3 was exposed to three cycles (4 days 66% of chow intake + 4 days food ad libitum) of yo-yo dieting but not stressed; and group 4 was exposed to cyclic yo-yo dieting and then stressed. All groups were fed highly palatable food (HPF) for 2 h on days 5–6 and 13–14. Acute stress was elicited by exposing rats to HPF, but preventing them from access to it for 15 min. Results  The combination of cyclic food restriction and stressful exposure to food markedly increased HPF intake. Sibutramine and fluoxetine inhibited food intake in all conditions. Topiramate selectively inhibited compulsive HPF intake in rats submitted to caloric restriction and stress. Midazolam increased HPF intake. Conclusions  Pharmacological results suggest that this model, in addition to face validity as an isomorphic model of human binge eating, is endowed with good predictive validity.  相似文献   
945.

Introduction

The present study was designed to assess the antidepressant effects of UFP-101, a selective nociceptin/orphanin FQ peptide (NOP) receptor antagonist, in a validated animal model of depression: the chronic mild stress (CMS).

Materials and methods and Results

UFP-101 (5, 10 and 20 nmol/rat; i.c.v., once a day for 21 days) dose- and time-dependently reinstated sucrose consumption in stressed animals without affecting the same parameter in non-stressed ones. In the forced swimming test, UFP-101 reduced immobility of stressed rats from day 8 of treatment. After a 3-week treatment, rats were killed for biochemical evaluations. UFP-101 abolished increase in serum corticosterone induced by CMS and reverted changes in central 5-HT/5-HIAA ratio. The behavioural and biochemical effects of UFP-101 mimicked those of imipramine, the reference antidepressant drug, administered at the dose of 15 mg/kg (i.p.). Co-administration of nociceptin/orphanin FQ (5 nmol/rat, from day 12 to 21) prevented the effects of UFP-101. Brain-derived neurotrophic factor mRNA and protein in hippocampus were not reduced by CMS nor did UFP-101 modify these parameters.

Discussion and Conclusion

This study demonstrated that chronic treatment with UFP-101 produces antidepressant-like effects in rats subjected to CMS supporting the proposal that NOP receptors represent a candidate target for the development of innovative antidepressant drugs.  相似文献   
946.
947.
Cardiovascular disease (CVD) is an increasing concern for human immunodeficiency virus (HIV)-infected patients, and risk assessment is recommended in routine HIV care. The absolute cardiovascular risk in an individual is determined by several factors, and various algorithms may be applied. To date, few comparisons of HIV patients with persons of the same age from the general population have been conducted. We hypothesized that the calculated risk of CVD may be increased in HIV patients. The probability for acute coronary events within 10 y (Framingham Risk Score) and the probability for fatal cardiovascular disease (SCORE algorithm) were assessed in 403 consecutive HIV-positive subjects free from overt cardiovascular disease, as well as in 96 age- and gender-matched control subjects drawn from the general population living in the same geographical area. The average 10-y risk for acute coronary events (Framingham Risk Score) was 7.0%+/-5% in HIV subjects and 6.3%+/-5% in the control group (p =0.32). The 10-y estimated risk for cardiovascular mortality (SCORE algorithm) was 1.23%+/-2.3% and 0.83%+/-0.9%, respectively (p =0.01). The main contributor to the increased CVD risk was the high proportion of smokers, but not an increase in cholesterol level. In conclusion, a limited increase in estimated risk of CVD was found in HIV-infected patients compared to the general population. In HIV-infected individuals other factors of less value in the general population and not included in any cardiovascular algorithm might be important. In our patients intervention to modify traditional risk factors should be addressed primarily towards modifying smoking habits.  相似文献   
948.
BACKGROUND: Although the neurotrophin-inducible gene vgf is expressed in mammalian neurons and endocrine cells, limited data is available in man. AIM: The objective of the study was to map proVGF peptides in human endocrine cells during development, adulthood, hyperplasia, and tumors. METHODS: Antisera were generated against peptides related to internal cleavage or cleavage-amidation sites (rat proVGF(422-430) and human proVGF(298-306)-NH2) and the proVGF C-terminal ending (human proVGF(607-615)). Developing and normal adult endocrine cells, hyperplastic endocrine lesions (thyroid, parathyroid, lung, and stomach), and 120 tumors (102 endocrine) were studied. Immunogold electron microscopy was performed on normal adult pancreas and gut, and Western blotting was performed on extracts of control tissues and endocrine tumors. RESULTS: proVGF fragments were revealed in developing pituitary, gut, pancreas, and adrenal medulla from 10 gestational weeks, in normal adult pituitary and adrenal medulla, pancreatic glucagon, and insulin cells and gut serotonin cells, in hyperplastic thyroid calcitonin cells, lung P cells, gastric enterochromaffin-like cells, and gastrin cells, and in 88 of 102 endocrine tumors. At electron microscopy proVGF immunoreactivity was restricted to electron-dense granules. Western blotting revealed large molecular weight forms and cleavage fragments in both control tissues and tumor extracts. CONCLUSIONS: proVGF-related peptides are present in endocrine cells early during development and adulthood and increase in hyperplasia and tumors, and proVGF fragments could be novel diagnostic tools for endocrine cells and related lesions, including tumors.  相似文献   
949.
CONTEXT: Ghrelin, well-known modulator of food intake and energy balance, is a rather ubiquitous peptide involved in several endocrine and nonendocrine actions. A possible as-yet-unknown role for ghrelin in modulating luteal function has been suggested because both ghrelin and its receptor (GRLN-R) have been immunohistochemically detected in human corpus luteum. OBJECTIVE: We first investigated GRLN-R mRNA expression in midluteal phase human luteal cells. Ghrelin effect on basal and human chorionic gonadotropin (hCG)-stimulated progesterone (P) release was then analyzed. Finally, we investigated whether ghrelin could affect luteal release of vascular endothelial growth factor (VEGF), prostaglandin (PG) E(2), both luteotropic factors, and PGF(2alpha), luteolytic modulator. Ghrelin effect on both basal and hypoxia-stimulated VEGF luteal expression was analyzed. METHODS: Human luteal cells were incubated for 24 h with ghrelin (10(-13) to 10(-7) m) or hCG (100 ng/ml) or CoCl(2) (10 microm), chemical hypoxia, or with hCG or CoCl(2) in combination with ghrelin. Both GRLN-R mRNA and VEGF mRNA were evaluated by real-time RT-PCR. PGs and P release was assayed by RIA, whereas VEGF release by ELISA. RESULTS: GRLN-R mRNA expression was demonstrated in human luteal cells. Both basal and hCG-stimulated P release was significantly decreased by ghrelin, which was able to reduce PGE(2) and increase PGF(2alpha) luteal release. Both basal and hypoxia-stimulated VEGF release was significantly decreased by ghrelin, which did not affect VEGF mRNA luteal expression. CONCLUSIONS: The present in vitro study provides the first evidence of a direct inhibitory influence of ghrelin on human luteal function.  相似文献   
950.
Primary hypobetalipoproteinemia (HBL) includes a group of genetic disorders: abetalipoproteinemia (ABL) and chylomicron retention disease (CRD), with a recessive transmission, and familial hypobetalipoproteinemia (FHBL) with a co-dominant transmission. ABL and CRD are rare disorders due to mutations in the MTP and SARA2 genes, respectively. Heterozygous FHBL is much more frequent. FHBL subjects often have fatty liver and, less frequently, intestinal fat malabsorption. FHBL may be linked or not to the APOB gene. Most mutations in APOB gene cause the formation of truncated forms of apoB which may or may be not secreted into the plasma. Truncated apoBs with a size below that of apoB-30 are not detectable in plasma; they are more frequent in patients with the most severe phenotype. Only a single amino acid substitution (R463W) has been reported as the cause of FHBL. Approximately 50% of FHBL subjects are carriers of pathogenic mutations in APOB gene; therefore, a large proportion of FHBL subjects have no apoB gene mutations or are carriers of rare amino acid substitutions in apoB with unknown effect. In some kindred FHBL is linked to a locus on chromosome 3 (3p21) but the candidate gene is unknown. Recently a FHBL plasma lipid phenotype was observed in carriers of mutations of the PCSK9 gene causing loss of function of the encoded protein, a proprotein convertase which regulates LDL-receptor number in the liver. Inactivation of this enzyme is associated with an increased LDL uptake and hypobetalipoproteinemia. HBL carriers of PCSK9 mutations do not develop fatty liver disease.  相似文献   
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