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There has been a growing interest over the past few years in the impact of male nutrition on fertility. Infertility has been linked to male overweight or obesity, and conventional semen parameter values seem to be altered in case of high body mass index (BMI). A few studies assessing the impact of BMI on sperm DNA integrity have been published, but they did not lead to a strong consensus. Our objective was to explore further the relationship between sperm DNA integrity and BMI, through a 3-year multicentre study. Three hundred and thirty male partners in subfertile couples were included. Using the terminal uridine nick-end labelling (TUNEL) assay, we observed an increased rate of sDerm DNA damage in obese men (odds ratio (95% confidence interval): 2.5 (1.2-5.1)).  相似文献   
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Many rhythmically active networks involve heterogeneous populations of pacemaker neurons with potentially distinct synaptic outputs that can be differentially targeted by extrinsic inputs or neuromodulators, thereby increasing possible network output patterns. To understand the roles of heterogeneous pacemaker neurons, we characterized differences in synaptic output from the anterior burster (AB) and pyloric dilator (PD) neurons in the lobster pyloric network. These intrinsically distinct neurons are strongly electrically coupled, coactive, and constitute the pyloric pacemaker ensemble. During pyloric oscillations, the pacemaker neurons produce compound inhibitory synaptic connections to the follower lateral pyloric (LP) and pyloric constrictor (PY) neurons, which fire out of phase with AB/PD and with different delay times. Using pharmacological blockers, we separated the synapses originating from the AB and PD neurons and investigated their temporal dynamics. These synapses exhibited distinct short-term dynamics, depending on the presynaptic neuron type, and had different relative contributions to the total synaptic output depending on waveform shape and cycle frequency. However, paired comparisons revealed that the amplitude or dynamics of synapses from either the AB or PD neuron did not depend on the postsynaptic neuron type, LP or PY. To address the functional implications of these findings, we examined the correlation between synaptic inputs from the pacemakers and the burst onset phase of the LP and PY neurons in the ongoing pyloric rhythm. These comparisons showed that the activity of the LP and PY neurons is influenced by the peak phase and amplitude of the synaptic inputs from the pacemaker neurons.  相似文献   
65.
Complex regulation of T cell functions during pregnancy is required to ensure materno-fetal tolerance. Here we reveal a novel pathway for the temporary suppression of maternal T cell responses in uncomplicated human pregnancies. Our results show that arginase activity is significantly increased in the peripheral blood of pregnant women and remarkably high arginase activities are expressed in term placentae. High enzymatic activity results in high turnover of its substrate L-arginine and concomitant reduction of this amino acid in the microenvironment. Amino acid deprivation is emerging as a regulatory pathway of lymphocyte responses and we assessed the consequences of this enhanced arginase activity on T cell responses. Arginase-mediated L-arginine depletion induces down-regulation of CD3 zeta, the main signalling chain of the TCR, and functional T cell hyporesponsiveness. Importantly, this arginase-mediated T cell suppression was reversible, as inhibition of arginase activity or addition of exogenous L-arginine restored CD3 zeta chain expression and T cell proliferation. Thus, L-arginine metabolism constitutes a novel physiological mechanism contributing to the temporary suppression of the maternal immune response during human pregnancy.  相似文献   
66.
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by progressive death of cortical and spinal motor neurons, for which there is no effective treatment. Using a cell-based assay for compounds capable of preventing motor neuron cell death in vitro, a collection of approximately 40,000 low-molecular-weight compounds was screened to identify potential small-molecule therapeutics. We report the identification of cholest-4-en-3-one, oxime (TRO19622) as a potential drug candidate for the treatment of ALS. In vitro, TRO19622 promoted motor neuron survival in the absence of trophic support in a dose-dependent manner. In vivo, TRO19622 rescued motor neurons from axotomy-induced cell death in neonatal rats and promoted nerve regeneration following sciatic nerve crush in mice. In SOD1(G93A) transgenic mice, a model of familial ALS, TRO19622 treatment improved motor performance, delayed the onset of the clinical disease, and extended survival. TRO19622 bound directly to two components of the mitochondrial permeability transition pore: the voltage-dependent anion channel and the translocator protein 18 kDa (or peripheral benzodiazepine receptor), suggesting a potential mechanism for its neuroprotective activity. TRO19622 may have therapeutic potential for ALS and other motor neuron and neurodegenerative diseases.  相似文献   
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The association between dementia and smoking or alcohol use has been examined in several epidemiological studies. In many case-control studies, a decreased risk of dementia or Alzheimer's disease (AD) was observed among smokers. However, when this association was analysed in prospective studies, an increased risk of AD was observed. In addition, in the PAQUID study, we showed that the decreased risk disappeared after adjustment for educational level and occupation. These factors are strong confounders in the association between dementia and tobacco use. We also showed that moderate consumption of wine was associated with a lower risk of developing AD. This result remains unchanged after adjustment for many potential confounders. The association between moderate alcohol consumption and risk of developing a dementia or AD was recently confirmed by prospective studies. In some studies, wine consumption was more specifically associated with a decreased risk, whereas beer or spirit consumption was not associated. These results suggest that tobacco consumption is not associated with a lower risk of dementia and that moderate alcohol intake does not increase the risk of developing dementia.  相似文献   
69.
Graefe's Archive for Clinical and Experimental Ophthalmology - To report the effectiveness of intravitreal aflibercept (IVT-AFL) treatment for diabetic macular edema (DME) in French clinical...  相似文献   
70.
The incidence of glioblastoma (GBM) has increased in patients aged 70 years or older, and will continue to grow. Elderly GBM patients have been excluded from most clinical trials; furthermore, optimal care management as well as benefit/risk ratio of GBM treatments are still being debated. This study describes oncological patterns of care, prognostic factors, and survival for patients ≥70 years in France. We identified patients over 70 with newly diagnosed and histologically confirmed GBM on data previously published by the French Brain Tumor DataBase. We included 265 patients. Neurological deficits and mental status disorders were the most frequent symptoms. The surgery consisted of resection (RS n?=?95) or biopsy (B n?=?170); 98 patients did not have subsequent oncological treatment. After surgery, first-line treatment consisted of radiotherapy (RT n?=?76), chemotherapy (CT n?=?52), and concomitant radiochemotherapy (CRC n?=?39). The median age at diagnosis was 76, 74, and 73 years, respectively, for the untreated, B?+?RT and/or CT, RS?±?RT and/or CT groups. Median survival (in days, 95 % CI) with these main strategies, when analyzed according to surgical groups, was: B-CT n?=?41, 199[155–280]; B-CRC n?=?21, 318[166–480]; B-RT n?=?37, 149[130–214]; RS-CT n?=?11, 245[211–na]; RS-CRC n?=?18, 372[349–593]; RS-RT n?=?39, 269[218–343]. This population study for elderly GBM patients is one of the most important in Europe, and could be considered as a historical cohort to compare future treatments. Moreover, we can hypothesize that elderly patients (versus patients <70 years) are undertreated. Karnofsky performance status seems to be the most relevant clinical predictive factor, and RS and CRC have a positive impact on survival for elderly GBM patients in the general population, at least when feasible.  相似文献   
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