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991.
Smadar Nahaliel Eliane Sommerfeld Israel Orbach Aron Weller Alan Apter Gil Zalsman 《Comprehensive psychiatry》2014
Background
This study used path-analysis to examine the assumption that the presence of mental pain in adults mediates the relationship between self-destruction, number of losses experienced in one’s life, and suicidal tendency.Methods
Fifty suicidal inpatients, 50 non-suicidal inpatients and 50 healthy volunteers were assessed for self-destruction, losses experienced, depression, suicidal tendency, and mental pain.Results
Self-destruction was found to have both a direct effect on suicidal tendency as well as one mediated by the presence of mental pain. Number of losses effected suicidal tendency only indirectly, mediated by the presence of mental pain. Overall, self-destruction was a more significant determinant of suicidal tendency than were the number of losses experienced during one’s life. A competing model, with depression replacing mental pain as the mediator, was also found to fit the data.Discussion
These findings provide evidence that the presence of mental pain is a mediator in the relationships between both self-destruction and number of losses experienced, and between suicidal tendencies. More studies are needed in order to further differentiate between mental pain and depression as mediators in suicidal tendency. 相似文献992.
Alan E. Jones 《Chest》2012,141(5):1362-1363
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One of the hallmarks of polycystic ovary syndrome (PCOS) is increased ovarian androgen secretion that contributes to the ovarian, hormonal, and metabolic features of this condition. Thecal cells from women with PCOS have an enhanced capacity for androgen synthesis. To investigate whether this propensity is a potential cause, rather than a consequence, of PCOS, we used an ovine prenatal androgenization model of PCOS and assessed ewes at 11 months of age. Pregnant Scottish Greyface ewes were administered 100 mg testosterone propionate (TP) or vehicle control twice weekly from d 62 to 102 of gestation, and female offspring (TP = 9, control = 5) were studied. Prenatal TP exposure did not alter ovarian morphology or cyclicity, or plasma androgen, estrogen, and gonadotropin concentrations, at this stage. However, follicle function was reprogrammed in vivo with increased proportions of estrogenic follicles (P < 0.05) in the TP-exposed cohort. Furthermore, in vitro the thecal cells of follicles (>4 mm) secreted more LH-stimulated androstenedione after prenatal androgenization (P < 0.05), associated with increased basal expression of thecal StAR (P < 0.01), CYP11A (P < 0.05), HSD3B1 (P < 0.01), CYP17 (P < 0.05), and LHR (P < 0.05). This provides the first evidence of increased thecal androgenic capacity in the absence of a PCOS phenotype, suggesting a thecal defect induced during fetal life. 相似文献
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Tartarin P Guibert E Touré A Ouiste C Leclerc J Sanz N Brière S Dacheux JL Delaleu B McNeilly JR McNeilly AS Brillard JP Dupont J Foretz M Viollet B Froment P 《Endocrinology》2012,153(7):3468-3481
AMP-activated protein kinase (AMPK), a key regulator of cellular energy homeostasis, is present in metabolic tissues (muscle and liver) and has been identified as a modulator of the female reproductive functions. However, its function in the testis has not yet been clearly defined. We have investigated the potential role of AMPK in male reproduction by using transgenic mice lacking the activity of AMPK catalytic subunit α1 gene [α1AMPK knockout (KO)]. In the testis, the α1AMPK subunit is expressed in germ cells and also in somatic cells (Sertoli and Leydig cells). α1AMPK KO male mice show a decrease in fertility, despite no clear alteration in the testis morphology or sperm production. However, in α1AMPK(-/-) mice, we demonstrate that spermatozoa have structural abnormalities and are less motile than in control mice. These spermatozoa alterations are associated with a 50% decrease in mitochondrial activity, a 60% decrease in basal oxygen consumption, and morphological defects. The α1AMPK KO male mice had high androgen levels associated with a 5- and 3-fold increase in intratesticular cholesterol and testosterone concentrations, respectively. High concentrations of proteins involved in steroid production (3β-hydroxysteroid dehydrogenase, cytochrome steroid 17 alpha-hydroxylase/17,20 lysate, and steroidogenic acute regulatory protein) were also detected in α1AMPK(-/-) testes. In the pituitary, the LH and FSH concentrations tended to be lower in α1AMPK(-/-) male mice, probably due to the negative feedback of the high testosterone levels. These results suggest that total α1AMPK deficiency in male mice affects androgen production and quality of spermatozoa, leading to a decrease in fertility. 相似文献
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Theken KN Schuck RN Edin ML Tran B Ellis K Bass A Lih FB Tomer KB Poloyac SM Wu MC Hinderliter AL Zeldin DC Stouffer GA Lee CR 《Atherosclerosis》2012,222(2):530-536
ObjectivePreclinical and genetic epidemiologic studies suggest that modulating cytochrome P450 (CYP)-mediated arachidonic acid metabolism may have therapeutic utility in the management of coronary artery disease (CAD). However, predictors of inter-individual variation in CYP-derived eicosanoid metabolites in CAD patients have not been evaluated to date. Therefore, the primary objective was to identify clinical factors that influence CYP epoxygenase, soluble epoxide hydrolase (sEH), and CYP ω-hydroxylase metabolism in patients with established CAD.MethodsPlasma levels of epoxyeicosatrienoic acids (EETs), dihydroxyeicosatrienoic acids (DHETs), and 20-hydroxyeicosatetraenoic acid (20-HETE) were quantified by HPLC–MS/MS in a population of patients with stable, angiographically confirmed CAD (N = 82) and healthy volunteers from the local community (N = 36). Predictors of CYP epoxygenase, sEH, and CYP ω-hydroxylase metabolic function were evaluated by regression.ResultsObesity was significantly associated with low plasma EET levels and 14,15-EET:14,15-DHET ratios. Age, diabetes, and cigarette smoking also were significantly associated with CYP epoxygenase and sEH metabolic activity, while only renin-angiotensin system inhibitor use was associated with CYP ω-hydroxylase metabolic activity. Compared to healthy volunteers, both obese and non-obese CAD patients had significantly higher plasma EETs (P < 0.01) and epoxide:diol ratios (P < 0.01), whereas no difference in 20-HETE levels was observed (P = NS).ConclusionsCollectively, these findings suggest that CYP-mediated eicosanoid metabolism is dysregulated in certain subsets of CAD patients, and demonstrate that biomarkers of CYP epoxygenase and sEH, but not CYP ω-hydroxylase, metabolism are altered in stable CAD patients relative to healthy individuals. Future studies are necessary to determine the therapeutic utility of modulating these pathways in patients with CAD. 相似文献
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