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101.
The orexins A (oxA) and B are peptides discovered in the rat hypothalamus and successively found in some peripheral organs of the mammalian body. They binds two protein G-coupled receptors defined receptor 1 (ox1r) and 2 for orexins, the first of which is highly specific for oxA while the second binds both the peptides with equal affinity. This work aimed to detect the presence of oxA and ox1r in the testis of the South American camelid alpaca (Vicugna pacos) and investigate the role played by them on Leydig cell steroidogenesis. The species alpaca acquired, in the last years, increasing zootechnical interest for the quality of the wool produced and its breeding spread from the country of origin to USA, Australia and Europe. Immunohistochemistry allowed us to detect oxA in Leydig and Sertoli cells, spermatogonia, resting spermatocytes, round and oval spermatids. Ox1r-immunoreactivity was found in Leydig cells and round, oval and elongated spermatids. The expression of the two peptides in tissue extracts was established by using Western blotting technique. Such results demonstrated that in the alpaca testis exists in a cellular complex able to produce and/or internalize oxA. Finally, the effect of oxA on steroidogenesis was investigated by means of in vitro cultured thin testis slices which were added with oxA or/and Müllerian Inhibiting Substance (MIS), a steroidolitic agent basally produced by the Sertoli cell. OxA evoked increase of testosterone production while MIS a decrease. The consecutive addition of oxA and MIS, or vice versa, highlighted an antagonistic interplay between the two substances which has been thought to be the main molecular event at the basis of the oxA-stimulated steroidogenesis mechanism.  相似文献   
102.
Although pulmonary embolism (PE) and deep vein thrombosis (DVT) share many risk factors, it is uncertain whether thrombophilic abnormalities may impact differently on the development of these two clinical manifestations of venous thromboembolism (VTE). To give further insight into this issue, we estimated the association of PE with different types of thrombophilia and evaluated whether these abnormalities have a different prevalence in patients presenting with PE, alone or associated with DVT, as compared with those with isolated DVT. In this study 443 consecutive patients with a first episode of VTE and 304 matched healthy controls underwent laboratory screening for thrombophilia, including natural anticoagulants, factor V Leiden and prothrombin G20210A polymorphisms, antiphospholipid antibodies, homocysteine, factor VIII, and lipoprotein(a). Of the 443 patients, 224 patients had isolated DVT, 144 had combined DVT/PE, and 75 had isolated PE. At least one thrombophilic abnormality was detected in 72.8% of DVT, 66% of DVT/EP, and 60% of isolated PE patients. A high prevalence of hyperhomocysteinemia and elevated lipoprotein(a) levels was found in all patients with no significant differences among the three groups. The prevalence of prothrombin G20210A polymorphism and of elevated factor VIII levels was significantly higher in patients with DVT and DVT/PE than in controls, but not in those with isolated PE, whereas factor V Leiden polymorphism was associated with isolated DVT but not with DVT/PE or isolated PE. In conclusion, the thrombophilic burden seems different in isolated PE versus DVT with or without PE, suggesting that PE may encompass a different pathophysiological process of thrombosis to DVT.  相似文献   
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The relationship between low-density lipoprotein receptor-related protein-1 (LRP1) and von Willebrand factor (VWF) has remained elusive for years. Indeed, despite a reported absence of interaction between both proteins, liver-specific deletion of LRP1 results in increased VWF levels. To investigate this discrepancy, we used mice with a macrophage-specific deficiency of LRP1 (macLRP1(-)) because we previously found that macrophages dominate VWF clearance. Basal VWF levels were increased in macLRP1(-) mice compared with control mice (1.6 ± 0.4 vs 1.0 ± 0.4 U/mL). Clearance experiments revealed that half-life of human VWF was significantly increased in macLRP1(-) mice. Ubiquitous blocking of LRP1 or additional lipoprotein receptors by overexpressing receptor-associated protein in macLRP1(-) mice did not result in further rise of VWF levels (0.1 ± 0.2 U/mL), in contrast to macLRP1(+) mice (rise in VWF, 0.8 ± 0.4 U/mL). This points to macLRP1 being the only lipoprotein receptor regulating VWF levels. When testing the mechanism(s) involved, we observed that VWF-coated beads adhered efficiently to LRP1 but only when exposed to shear forces exceeding 2.5 dyne/cm(2), implying the existence of shear stress-dependent interactions. Furthermore, a mechanism involving β2-integrins that binds both VWF and LRP1 also is implicated because inhibition of β2-integrins led to increased VWF levels in control (rise, 0.19 ± 0.16 U/mL) but not in macLRP1(-) mice (0.08 ± 0.15 U/mL).  相似文献   
104.
INTRODUCTION: The objective of this study was to compare, in a naturalistic setting, the efficacy and tolerability of selective serotonin reuptake inhibitors (paroxetine, sertraline, citalopram) and venlafaxine, in 120 depressed inpatients. This paper attempts to review which variables may influence a physician's choice of a specific antidepressant for a specific patient. METHOD: Patients were assessed using the Hamilton Psychiatric Rating Scale for Depression (HAM-D), the Montgomery-Åsberg Depression Rating Scale (MADRS), the Clinical Global Impression (CGI) and the Symptoms Check List (SCL-90). The two groups under assessment were comparable in all socio-demographic characteristics. We used logistic regression analyses to identify variables that differentiate the two groups at baseline. This, in turn, would represent those variables with the potential to influence a physician's selection of an antidepressant. RESULTS: Venlafaxine patients reported significantly worse scores on MADRS at baseline, but any difference was no longer present at discharge. We found no significant variation in the efficacy of the antidepressants under study and there were no differences in the incidence and profiles of adverse events between the groups of patients. CONCLUSION: The degree of severity of the actual depressive picture appears to influence choice in favour of venlafaxine. However, it appears that the choice of SSRIs is more closely linked to patients who present a previous history of non-mood psychiatric symptoms.  相似文献   
105.
The objective of this study was to analyze the impact of family history of suicidal behaviour on psychopathlogical features of inmates. A sample of 1,179 prisoners had a psychiatric interview including the Brown-Goodwin Assessment for Lifetime History of Aggression (BGLHA). Prisoners completed the Barratt Impulsivity Scale (BIS), Buss-Durkee Hostility Inventory (BDHI), and Eysenck Personality Questionnaire (EPQ). Prisoners with a family history of suicide were compared with prisoners without a family history of suicide on clinical and personality variables. Seventy of the 1,179 prisoners (5.9%) had a family history of suicide. Significantly more FHS positive prisoners had attempted suicide compared with FHS negative prisoners (36% vs. 12%, P < 0.0001). Significantly more FHS positive prisoners had a previous history of convictions, a history of juvenile convictions, and had exhibited aggressive behavior in jail. FHS positive prisoners had significantly higher aggression scores on the BGLHA, higher hostility scores on the BDHI, higher impulsivity scores on the BIS, and higher neuroticism scores on the EPQ. A family history of suicide may be a useful clinical indicator that a prisoner is at increased risk for suicidal behaviour and may have problems with impulsive-aggression.  相似文献   
106.
Patients with Parkinson’s disease (PD) may present delusional jealousy (DJ). In a previous cross-sectional prevalence study we identified 15 cognitively preserved and five demented PD patients with DJ. The current study aimed at evaluating their clinical (motor and non-motor) characteristics and the pharmacological treatments associated with DJ, and its subsequent pharmacological management. Patients were assessed by neurologists and psychiatrists using the Hoehn and Yahr scale, the Unified Parkinson’s Disease Rating Scale, the Brief Psychiatric Rating Scale, the Beck Depression Inventory, the Hamilton Anxiety Scale and the Neuropsychiatric Inventory. Efficacy of DJ management was evaluated in follow-up visits. All patients were in therapy with dopamine agonists. A subgroup of five cognitively preserved patients developed DJ after a short period of treatment of therapy with dopamine agonists, while other patients developed DJ after a longer period of dopaminergic treatment. Psychiatric comorbidities were common in cognitively preserved and in demented patients. The pharmacological management included the interruption of dopamine agonists in two patients and the reduction of dopamine agonist dose plus the use of antipsychotics in other patients. These clinical data suggest that the management of medicated PD patients should include investigation for the presence of DJ and the evaluation of clinical characteristics potentially relevant to the prevention or the early recognition of delusions.  相似文献   
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We describe a case of longitudinal stent compression induced by withdrawal of a "buddy wire," which we managed by crushing the retracted struts using another stent. To the best of our knowledge, this is one of the first reports of this complication induced by wire manipulation.  相似文献   
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