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Since its’ discovery over 20 years ago, BDNF has been shown to play a key role in neuronal survival, in promoting neuronal regeneration following injury, regulating transmitter systems and attenuating neural-immune responses. Estrogen’s actions in the young and mature brain, and its role in neurodegenerative diseases in many cases overlaps with those observed for BDNF. Reduced estrogen and BDNF are observed in patients with Parkinson’s disease and Alzheimer’s disease, while high estrogen levels are a risk factor for development of multiple sclerosis. Estrogen receptors, which transduce the actions of estrogen, colocalize to cells that express BDNF and its receptor trkB, and estrogen further regulates the expression of this neurotrophin system. This review describes the distribution of BDNF and trkB expressing cells in the forebrain, and the roles of estrogen and the BDNF–trkB neurotrophin system in Parkinson’s disease, Alzheimer’s disease and multiple sclerosis. 相似文献
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AIM: To determine the prevalence of Hp infection in patients with chronic urticaria (CU) and to evaluate the result of autologous serum skin test (ASST) in CU patients with Hp infections. METHODS: In this cross-sectional study, 16 patients with chronic urticaria and 16 non-urticaria volunteers were investigated (matched for age and sex). All subjects were examined for Hp infection with the 13C-urea breath test. Autologous serum skin test was performed in patients with proven Hp infection. RESULTS: Helicobacter pylori was detected in 12.5% of patients and 0% of the control group. There was no significant difference between the two groups (p = 0.484 using Fisher exact test). Autologous serum skin test was positive in 1 of 2 CU patients with Hp infection. CONCLUSION: In this study, there was no significant difference in the seroprevalence of Hp infection between CU patients and controls. Autologous serum skin test was positive in 1 of 2 CU patients with Hp infection. 相似文献
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Pietro Leccese Yesim Ozguler Robin Christensen Sinem Nihal Esatoglu Dongsik Bang Bahram Bodaghi Aykut Ferhat Celik Farida Fortune Julien Gaudric Ahmet Gül Ina Kötter Alfred Mahr Robert J. Moots Jutta Richter David Saadoun Carlo Salvarani Francesco Scuderi Petros P. Sfikakis Gulen Hatemi 《Seminars in arthritis and rheumatism》2019,48(4):752-762
Objectives
The aim of this systematic review was to inform the update of European League Against Rheumatism (EULAR) Recommendations for the management of Behçet’s syndrome (BS), on the evidence for the treatment of skin, mucosa and joint involvement of BS.Methods
A systematic literature search, data extraction, statistical analyses and assessment of the quality of evidence were performed according to a pre-specified protocol using the PRISMA guidelines. Studies that assessed the efficacy of an intervention in comparison to an active comparator or placebo for oral ulcers, genital ulcers, papulopustular lesions, nodular lesions or arthritis were included. Where possible, risk ratios were calculated for binary outcomes and mean difference for continuous outcomes.Results
Among the 3927 references that were screened, 37 were included in the analyses. Twenty-seven of these assessed mucocutaneous and 17 assessed joint involvement. Twenty-one of these studies were randomised controlled trials (RCTs). RCTs with colchicine, azathioprine, interferon-alpha, thalidomide, etanercept and apremilast showed beneficial results with some differences according to lesion type and gender. These agents were generally well tolerated with few adverse events causing withdrawal from the study.Conclusions
RCTs comprised more than a half (21/37, 57%) of the sources included in the evidence synthesis related to skin, mucosa and joint involvement applicable for the EULAR Recommendations for the management of BS. Differences in the outcome measures that were used across the included studies often made it difficult to combine and compare the results. 相似文献47.
Sajapitak S Iwata K Shahab M Uenoyama Y Yamada S Kinoshita M Bari FY I'Anson H Tsukamura H Maeda K 《Endocrinology》2008,149(6):3016-3024
The present study aims to clarify the role of fatty acids in regulating pulsatile LH secretion in rats. To produce an acute central lipoprivic condition, mercaptoacetate (MA), an inhibitor of fatty acids oxidation, was administered into the fourth cerebroventricle (4V) in ad libitum fed ovariectomized (OVX) rats (0.4, 2, and 10 micromol/rat) with or without an estradiol (E2) implant producing diestrus plasma E2 levels. Pulsatile LH secretion was suppressed by 4V MA administration in a dose-dependent manner in both OVX and OVX plus E2 rats. Mean LH levels and LH pulse frequency and amplitude were significantly reduced by the highest dose of MA in OVX rats, and by the middle and highest dose of MA in E2-treated rats, suggesting that estrogen enhanced LH suppression. Blood glucose levels increased immediately after the highest dose of MA in both groups. Fourth ventricular injection of trimetazidine (2 and 3 micromol/rat), another inhibitor of fatty acids oxidation, also inhibited pulsatile LH release, resulting in significant and dose-dependent suppression of LH pulse frequency and an increase in blood glucose levels in OVX plus E2 rats. In contrast, peripheral injection of the highest 4V dose of MA (10 micromol/rat) did not alter LH release or blood glucose levels. Microdialysis of the hypothalamic paraventricular nucleus (PVN) revealed that norepinephrine release in the region was increased by 4V MA administration. Preinjection of alpha-methyl-p-tyrosine, a catecholamine synthesis inhibitor, into the PVN completely blocked the lipoprivic inhibition of LH and the counter-regulatory increase in blood glucose levels in OVX plus E2 rats. Together, these studies indicate that fatty acid availability may be sensed by a central detector, located in the lower brainstem to maintain reproduction, and that noradrenergic inputs to the PVN mediate this lipoprivic-induced suppression of LH release. 相似文献
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The relative accuracies of ECG precordial lead waveforms derived from EASI leads and those acquired from paramedic applied standard leads 总被引:2,自引:0,他引:2
Sejersten M Pahlm O Pettersson J Clemmensen PM Rautaharju F Zhou S Maynard C Feldman CL Wagner GS 《Journal of electrocardiology》2003,36(3):179-185
Accurate precordial electrode placement can be difficult in emergency situations leading either to loss of time or diminished accuracy. A possible solution is the quasi-orthogonal EASI lead system, with only five electrodes and easily defined landmarks to provide a derived 12-lead electrocardiogram (ECG). The purpose of this study was to test the hypothesis that precordial waveforms in EASI-derived ECGs have no greater deviation from those in gold standard ECGs, than do the precordial waveforms in paramedic acquired standard ECGs. Twenty paramedics applied the standard precordial electrodes employing the routine procedure. A certified ECG technician applied the 6 standard precordial electrodes in their correct gold standard positions, and the EASI electrodes. 12-lead ECGs were obtained from the paramedics' standard leads, and derived from the EASI leads, for comparison with the gold standard ECG. In each precordial lead recording, 6 computer-measured QRS-T waveform parameters were considered. Differences between deltaEASI-gold standard versus deltaparamedic-gold standard were calculated for every waveform in every lead resulting in 720 comparisons. EASI and paramedic results were "equally accurate" in 47%, the paramedic was more accurate in 31%, and EASI was more accurate in the remaining 22%. The differences from gold standard recording of precordial waveforms in ECGs derived from the EASI leads and those acquired via paramedic-applied standard electrodes are similar. The results suggest that the EASI lead system may provide an alternative to the standard ECG precordial leads to facilitate data acquisition and possibly save valuable time in emergency situations. 相似文献
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