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101.
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Orthostatic hypotension (OH) is a frequent nonmotor feature of Parkinson’s disease (PD), and its occurrence has been associated with cognitive impairment. The underlying mechanism could be mediated by development of cerebrovascular disease induced by chronic or episodic hypoperfusion, but the extent of brain vascular load in PD patients with OH has never been investigated. This study aimed to assess the relationship between OH and cognitive function in PD patients and to investigate the contribution of brain vascular lesions. Forty-eight PD patients underwent a tilt table test (TT) to assess supine and orthostatic blood pressure as well as an extensive neuropsychological evaluation to evaluate cognitive function. Brain magnetic resonance imaging was acquired in 44/48 patients and analyzed by a visual semiquantitative scale. Twenty-three patients presented OH at TT (13/23 were symptomatic), and 25 did not. There were no differences in motor severity or disease duration between patients with and without OH. In patients with OH we found significantly worse cognitive performance in specific tasks, such as sustained attention, visuospatial and verbal memory, compared with patients without OH. However, there were no differences in vascular burden between the two groups. Our study confirms that there is an association between OH and selective cognitive deficits in PD, but rebuts the hypothesis that this is underlined by the development of cerebrovascular disease.  相似文献   
103.
We studied how nicotinic acetylcholine receptors (nAChRs) regulate glutamate release in the secondary motor area (Fr2) of the dorsomedial murine prefrontal cortex, in the presence of steady agonist levels. Fr2 mediates response to behavioral situations that require immediate attention and is a candidate for generating seizures in the frontal epilepsies caused by mutant nAChRs. Morphological analysis showed a peculiar chemoarchitecture and laminar distribution of pyramidal cells and interneurons. Tonic application of 5 µM nicotine on Layer V pyramidal neurons strongly increased the frequency of spontaneous glutamatergic excitatory postsynaptic currents. The effect was inhibited by 1 µM dihydro‐β‐erythroidine (which blocks α4‐containing nAChRs) but not by 10 nM methyllicaconitine (which blocks α7‐containing receptors). Excitatory postsynaptic currents s were also stimulated by 5‐iodo‐3‐[2(S)‐azetidinylmethoxy]pyridine, selective for β2‐containing receptors, in a dihydro‐β‐erythroidine ‐sensitive way. We next studied the association of α4 with different populations of glutamatergic terminals, by using as markers the vesicular glutamate transporter type (VGLUT) 1 for corticocortical synapses and VGLUT2 for thalamocortical projecting fibers. Immunoblots showed higher expression of α4 in Fr2, as compared with the somatosensory cortex. Immunofluorescence showed intense VGLUT1 staining throughout the cortical layers, whereas VGLUT2 immunoreactivity displayed a more distinct laminar distribution. In Layer V, colocalization of α4 nAChR subunit with both VGLUT1 and VGLUT2 was considerably stronger in Fr2 than in somatosensory cortex. Thus, in Fr2, α4β2 nAChRs are expressed in both intrinsic and extrinsic glutamatergic terminals and give a major contribution to control glutamate release in Layer V, in the presence of tonic agonist levels. Synapse 00:000–000, 2013 . © 2013 Wiley Periodicals, Inc.  相似文献   
104.
The aim of this study was to determine the effect of isolated psychological intimate partner violence and psychosocial factors (social support and alcohol or drug use by a partner/family member) on psychological well-being (depression or poor self-perceived health status) at 5 and 12 months post-partum. A longitudinal cohort study was carried out with a consecutive sample of 1,400 women in their first trimester of pregnancy, who attended the prenatal programme in the Valencia Region (Spain) in 2008 and were followed up at 5 months and 12 months post-partum. A logistic regression model was fitted using generalized estimating equations, to assess the effect of isolated psychological intimate partner violence, social support, alcohol consumption and illicit drug use problems by a partner or family member on subsequent psychological well-being at follow-up. We observed a decrease in the incidence of poorer psychological well-being (post-partum depression and poor self-perceived health status) at 12 months post-partum. The strongest predictor of poor psychological well-being was depression (AOR = 6.83, 95 % CI: 3.44–13.58) or poor self-perceived health status (AOR = 5.34, 95 % CI: 2.37–12.02) during pregnancy. Isolated psychological IPV increased the risk of a deterioration in psychological well-being. Having a tangible social network was also a predictor of both post-partum depression and poor self-perceived health status. The effect of functional social support varied according to the type of psychological well-being indicator being used. Problems of alcohol consumption or illicit drug use by a partner or family member were a predictor of post-partum depression only. Psychological well-being during the first year after birth is highly affected by isolated psychological IPV and psychosocial factors.  相似文献   
105.
The hepatitis C virus (HCV) infects more than 180 million people globally, with increasing incidence, especially in developing countries. HCV infection frequently progresses to liver cirrhosis leading to liver transplantation or death, and HCV recurrence still constitutes a major challenge for the transplant team. Antiviral therapy is the only available instrument to slow down this process, although its actual impact on liver histology, in responders and nonresponders, is still controversial. We are now facing a “new era” of direct antiviral agents that is already changing the approach to HCV burden both in the pre‐ and in the post‐liver transplantation settings. Available data on sofosbuvir/ledipasvir and sofosbuvir/simeprevir in patients with decompensated cirrhosis sustain a SVR12 of 89% 1 , but one‐third of patients do not clinically improved. The sofosbuvir/ribavirin treatment in stable cirrhotic patients with HCC before liver transplantation is associated with 2% recurrence rate if liver transplantation is performed at least one month after undetectable HCV‐RNA is achieved. The treatment of recurrence with the new antiviral drugs is associated with a SVR that ranges between 60 and 90%. In this review, we have focused on the evolution of antiviral therapy for HCV recurrence from the “old” interferon‐based therapy to the “new” interferon‐free regimens, highlighting useful information to aid the transplant hepatologist in the clinical practice.  相似文献   
106.
Biopsy‐proven acute cellular rejection (ACR) is the primary efficacy endpoint in most randomized trials evaluating immunosuppression in liver transplantation. However, ACR is not a major cause of graft loss, and a certain grade of immune activation may be even beneficial for long‐term graft acceptance. Validated criteria to select candidates for liver biopsy are lacking, and routine clinical practice relies on liver tests, which are inaccurate markers of ACR. Indeed, both the agreement among clinicians to select candidates for liver biopsy and the correlation between the clinical suspicion of ACR and histological findings are poor. In randomized trials evaluating immunosuppression protocols, this concern grows exponentially due to the open‐label and multicenter nature of most studies. Therefore, biopsy‐proven ACR is a suboptimal efficacy endpoint given its limited impact on prognosis and the heterogeneous diagnosis, which may increase the risk of bias. Chronic rejection and/or graft loss would be more appropriate endpoints, but would certainly require larger studies with prolonged surveillances. An objective method to select candidates for liver biopsy is therefore urgently needed, and only severe episodes of histological ACR should be considered as potentially harmful. Emerging surrogate markers of ACR and antibody‐mediated rejection require further investigation to determine their clinical role.  相似文献   
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Nicotine is known to decrease body weight in normal rodents and human smokers, whereas nicotine withdrawal or smoking cessation can increase body weight. We have found that mice fed a high fat diet do not show the anorectic effect of chronic nicotine treatment, but do increase their body weight following nicotine withdrawal. Nicotine withdrawal is accompanied by increased expression of the orexigenic peptides neuropeptide Y and Agouti-related protein in the hypothalamus, and decreased expression of the metabolic protein uncoupling protein-3 in brown adipose tissue. These data suggest that diet can influence the ability of nicotine to modulate body weight regulation and demonstrate that chronic nicotine exposure results in adaptive changes in central and peripheral molecules which regulate feeding behavior and energy metabolism.  相似文献   
110.
We describe the case of a young woman showing yolk sac tumors (YST) and a Sertoli-Leydig cell tumor (SLCT) in the right ovary, with recurrences in the right adnexum and with hepatic metastasis. To our knowledge, YST and SLCT have never been described as components of the same tumor or reported as associated in the same patient. The patient's karyotype showed the presence of Y chromosome inserted into the 1qh region; the inserted region corresponded to Yq12 heterochromatin. LOH analysis revealed 1p36 paternal allele loss in the proband tumor, thus supporting a germ cell origin for the tumor. The presence of Y heterochromatin in 1qh DNA might induce disturbances in the normal regulation of oncogenes located in 1q.  相似文献   
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