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We studied the influence of the rs1182 polymorphism of the TOR1A gene on the risk of dystonia spread in two representative cohorts of patients presenting with primary blepharospasm (BSP), one from Italy and the other from the United States of America. The relationship between rs1182 polymorphism and spread was estimated by Kaplan‐Meier survival curves and Cox proportional hazard regression models adjusted by age and sex, age of BSP onset. In both series, patients carrying the T allele (G/T or T/T) in the rs1182 polymorphism were more likely to have dystonia spread as compared with the homozygous carriers of the common G allele. The comparable findings obtained in two independent cohorts support a genetic contribution to BSP spread. © 2009 Movement Disorder Society  相似文献   
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BackgroundNo long-term, international, multicenter studies of the effectiveness and safety of the SAGB in morbid obesity have been previously published. The objective of this study was to assess the effectiveness and safety of the Swedish Adjustable Gastric Band (SAGB) at 6 bariatric centers in Australia, Europe, and Brazil, with ≤5 years of follow-up; the effect on patient covariates; and changes in co-morbidity.MethodsA 2-phase study design was used, involving both retrospective and prospective data. SAGB was implanted by way of the pars flaccida 1, 3, and 5 years previously. The retrospective phase entailed a review of the records. The prospective phase included a subset of eligible patients who agreed to undergo additional clinical assessments. The percentage of excess weight loss (%EWL), patient level predictors, change in co-morbidities, and complications were analyzed.ResultsA total of 481 patients in 3 mutually exclusive follow-up cohorts (1 yr, n = 200; 3 yr, n = 184; 5 yr, n = 97) participated in the present study. Of these 481 patients, 339 (1 yr, n = 139; 3 yr, n = 131; 5 yr, n = 69) underwent prospective evaluations. The mean %EWL was 43.5% ± 21.8%, 57.7% ± 25.9%, and 49.8% ± 27.6% and the mean change in body mass index was ?7.64, ?10.75, and ?9.52 in the 1-, 3-, and 5-year cohorts, respectively (P <.001). Gender and age did not predict the %EWL; however, a greater preoperative body mass index was inversely related to the %EWL. Longer postimplantation times were associated with greater improvement in co-morbidities and with greater frequencies of reoperation. Fewer than 15% of the patients in the 5-year cohort had undergone band removal and 10% required band revisions. No fatal or life-threatening complications occurred.ConclusionSAGB is safe and effective in inducing weight loss and improvement of co-morbidities in morbidly obese patients at international bariatric centers at 1, 3, and 5 years postoperatively.  相似文献   
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Background.

Environmental exposures to tobacco, alcohol, human papillomavirus (HPV) and/or Epstein‐Barr virus (EBV), all of which can perturb multiple cell cycle proteins or tumor suppressors, have been implicated in the pathogenesis of different subsets of head and neck cancers. The aim of this study was to investigate to which extent the virus infection by itself, and/or the altered cell cycle proteins, contributes to prognosis in locally advanced tonsillar squamous cell carcinomas (TSCCs) treated with concurrent chemoradiotherapy (CCRT) alone.

Methods.

Serial tumor tissue arrays from archival samples were tested for the presence of HPV genome integration or EBV episome by means of DNA sequencing, real‐time polymerase chain reaction (PCR), and in situ hybridization. Alterations of cell cycle proteins (p53, pRb, and p21) were evaluated by immunohistochemical staining. The association of viral presence with altered cell cycle proteins was correlated to clinical outcomes.

Results.

Of the 46 patients with the same T2N2bM0 stage IVA among consecutive patients with TSCC, 23 (50%) had integrated HPV DNA and only 1 (2%) had EBV episome. The HPV types detected were almost all HPV‐16. A reduced expression pattern of p53, pRb, and p21 was noted in HPV‐positive tumors, and the incremental number of alterations in the 3 proteins was significantly associated with HPV‐negative tumors. The presence or absence of HPV together with the number of altered expression of the 3 cell cycle markers resulted in further identification of 4 biologically and clinically distinct subgroups with different outcomes after CCRT.

Conclusions.

Use of combined biomarkers of oncogenic HPV and tumor suppressors of p53, pRb, and p21 in advanced TSCC provides prognostic molecular classification superior to the TNM stage system and identifies low‐risk patients for organ preservation by CCRT alone and high‐risk patients who might benefit from planned tonsillectomy and neck dissection before or after CCRT. © 2008 Wiley Periodicals, Inc. Head Neck, 2009  相似文献   
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Background

Vagus nerve stimulation (VNS) is a recent intervention for treatment-resistant depression. Electrophysiological recordings in the rat brain showed that VNS increases the firing rate of norepinephrine (NE) neurons after 1 day of stimulation and that of serotonin (5-HT) neurons after 14 days. This study was conducted to further characterize these effects.

Methods

We implanted rats with a VNS electrode and stimulator. We used the selective noradrenergic toxin DSP-4 to lesion NE neurons of the locus coeruleus. We recorded dorsal raphe 5-HT neurons under chloral hydrate anesthesia. We recorded hippocampus CA3 pyramidal neurons using 5-barreled iontophoretic pipettes.

Results

Analysis of a previously published data set revealed that VNS increased not only the spontaneous firing rates of NE neurons, but also the percentage of neurons firing in bursts. The enhancement of the 5-HT neuron firing rate by VNS was abolished by lesioning NE neurons. We found that VNS increased the degree of activation of postsynaptic α1-adrenoceptors on 5-HT neurons, probably through an increased release of endogenous NE. The tonic activation of postsynaptic 5-HT1A receptors in the hippocampus was enhanced after 14 days of VNS, as with other antidepressant treatments.

Limitations

Our study limitations include the fact that we turned off the stimulator during the electrophysiological recordings, which likely decreased the vagal tone to the brain. Also, we obtained the data while the animals were under anesthesia, therefore studies need to be carried out in unanesthetized rats to ascertain whether the anesthetic agent influenced the changes observed between control rats and those treated with VNS.

Conclusion

Vagus nerve stimulation initially increases the firing activity and pattern of NE neurons and subsequently those of 5-HT neurons, presumably as a cascade effect via α1-postsynaptic adrenoceptors. To date, VNS appears to be a unique antidepressant treatment increasing 5-HT transmission and enhancing the firing activity of NE neurons. These effects could contribute to the effectiveness of VNS in treatment-resistant depression.  相似文献   
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