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81.
Head and neck cancers affect more than half million person a year worldwide. More than 40% have an advanced stage at diagnosis. The incidence in Lebanon according to the statistics of the Ministry of Public Health was 268 new cases in 2007. The tumors and their treatment modalities have an important impact on the quality of life because they influence communication, breathing and4 swallowing. Treatment modalities are evolving to more conservative approaches for better functional results without impeding survival. We present in this review the state of the art of the management of head and neck cancer in 2011 with emphasis on the most recent advances in the assessment, treatment and follow-up.  相似文献   
82.
T‐cell‐based immunological memory has the potential to provide the host with life‐long protection against pathogen reexposure and thus offers tremendous promise for the design of vaccines targeting chronic infections or cancer. In order to exploit this potential in the design of new vaccines, it is necessary to understand how and when memory T cells acquire their poised effector potential, and moreover, how they maintain these properties during homeostatic proliferation. To gain insight into the persistent nature of memory T‐cell functions, investigators have turned their attention to epigenetic mechanisms. Recent efforts have revealed that many of the properties acquired among memory T cells are coupled to stable changes in DNA methylation and histone modifications. Furthermore, it has recently been reported that the delineating features among memory T cells subsets are also linked to distinct epigenetic events, such as permissive and repressive histone modifications and DNA methylation programs, providing exciting new hypotheses regarding their cellular ancestry. Here, we review recent studies focused on epigenetic programs acquired during effector and memory T‐cell differentiation and discuss how these data may shed new light on the developmental path for generating long‐lived CD8+ T‐cell memory.  相似文献   
83.
Pityriasis versicolor (PV) is a chronic superficial fungal infection. Management using azole drugs leads to drug resistance. The present study aimed to compare the clinical outcome of 0.1% adapalene gel vs 2% ketoconazole cream and their combination in PV. This randomized double‐blinded study was conducted on 90 PV patients divided into three equal groups. GI was treated with topical ketoconazole 2% cream twice daily and placebo, GII was treated with topical 0.1% adapalene gel twice daily and placebo and GIII was treated with topical combination of 0.1% adapalene gel (at night) and ketoconazole 2% cream (in the morning). All patients received medications for 4 weeks. Evaluation was done at 2 and 4 weeks and included clinical assessment, laboratory assessment, and patient satisfaction. We found that after 4 weeks of treatment, all groups showed significant improvement. There was better response in GIII in terms of lower rate of positive potassium hydroxide staining, higher rate of significantly improved cases and higher rate of well‐satisfied patients. However, the difference fell short of statistical significance. We concluded that a combination of adapalene gel and ketoconazole cream is very effective in treatment of PV with no or mild side effects.  相似文献   
84.
BackgroundThe freezing phenomenon is among the most disabling symptoms of Parkinson's disease (PD) manifesting most commonly as Freezing of Gait with a paroxysmal cessation of effective stepping. Recent studies have suggested that freezing is related to both impairments in conflict resolution as well as the processing of environmentally salient information.MethodsIn this study, we utilized a virtual reality gait paradigm to investigate differences in motor outflow between PD patients with (n = 36) and without (n = 37) Freezing of Gait, as well as age-matched healthy controls (n = 18). Subjects were required to navigate a realistic on-screen environment with the use of foot pedals to simulate stepping whilst responding to either cues associated with conflict resolution (congruent ‘Red’, ‘Green’ or ‘Blue’) or environmental salience (wide, narrow and sliding doorways). Footstep latency was used as a measure of motor output.ResultsSignificantly increased stepping latencies were observed in freezers compared to non-freezers (p = 0.004) and controls (p = 0.016) in response to stimuli requiring the inhibition of implicitly cued behavior (‘red’ cue). Patients with Freezing of Gait also demonstrated increased motor latency compared to non-freezers and controls specifically in response to environmentally salient triggers including narrow doorways (p = 0.03 and 0.01 respectively) and the opening of a sliding door (p = 0.036 and 0.048 respectively). Performance on the paradigm in relation to these triggers correlated significantly with self-reported freezing severity.ConclusionThese results suggest that deficits in conflict resolution and visuospatial processing may reflect some of the neural mechanisms associated with freezing behavior and that these can be probed in a virtual reality environment.  相似文献   
85.

Background.

Research biopsies are crucial for exploring the impact of novel agents on putative targets. The current study assesses the safety and success rate associated with performing such biopsies.

Methods.

We reviewed the medical records of 155 consecutive patients who had one or more research biopsies as part of a phase I trial from September 2004 to October 2009.

Results.

Of 281 research biopsies performed, 118 were paired before and after treatment biopsies (total = 236 biopsies). The most common sites of biopsy were superficial lymph node (19.9%), followed by liver (16.4%), and then soft tissue (15.7%). Ultrasound-guided biopsies were the most frequent type (53.7%). Among 142 patients who consented for mandatory biopsy, 86.6% had the biopsy performed, compared with 4.4% of 911 patients offered a biopsy on an optional basis (p < .0001). Biopsy was obtained most frequently on industry-sponsored trials; lack of funding on nonindustry trials was the most common reason that biopsies were not obtained. Of 281 single biopsies, only 4 (1.4%) had complications: pneumothorax requiring chest tube placement (n = 2), infection requiring admission (n = 1), and arrhythmia with hypotension (n = 1). All but one biopsy was successful in obtaining tissue. No deaths were attributable to biopsy.

Conclusions.

Our experience demonstrates that research biopsies in early phase clinical trials are safe (1.4% risk of serious complications), and a higher percentage of patients underwent mandatory biopsies (86.6%) compared with that of the patients with optional biopsies (4.4%).  相似文献   
86.
Aim of the workAssessment of synovitis in rheumatoid arthritis (RA) is a major issue for proper treatment; it has been proven that high resolution ultrasound (US) examination could be of valuable help. The B-cell chemokine, CXCL13, is a proposed serum biomarker of synovitis in RA. We aimed to find out the presence of synovitis in patients with recent-onset RA and its correlation with disease activity.Patients and methodsWe evaluated 30 patients with early RA for the presence and degree of synovitis by performing high resolution US and obtaining serum CXCL13 levels. In addition, we correlated these results with disease activity score 28 (DAS 28). Results of high resolution US and serum CXCL13 were also obtained for 20 healthy age- and sex-matched volunteers and served as controls.ResultsSerum CXCL13 level was significantly increased in early RA patients vs. controls (p < 0.001). High resolution US revealed that RA patients had a significant increased synovial thickness and high power Doppler US score. In RA patients, DAS 28 had a significant correlation with serum CXCL13 (r = 0.42, p = 0.02), synovial thickness (r = 0.39, p = 0.03) and power Doppler US score (r = 0.43, p = 0.02). Serum CXCL13 level correlated with synovial thickness (r = 0.63, p = 0.001) and power Doppler US score (r = 0.69, p = 0.001).ConclusionRecent-onset RA patients suffer from synovitis as evidenced by significantly increased serum CXCL13 and by high resolution US. Serum CXCL13 is a reliable marker of synovial inflammation which correlates better with synovial thickening and power Doppler US scores than DAS28.  相似文献   
87.

Background

Three protein products of ghrelin gene (acylated ghrelin, des-acylated ghrelin, and obestatin) are involved in appetite stimulation and suppression. Additionally, there is some evidence suggesting their involvement in metabolic and inflammatory pathways which may be implicated in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). The aim of this study was to examine the relationships of ghrelin gene products in patients with NAFLD.

Methods

We included 75 morbidly obese patients with biopsy-proven NAFLD (41 with histologic non-alcoholic steatohepatitis (NASH)) with clinical and laboratory data as well as frozen serum samples from the time of liver biopsy. Fasting serum was assayed for obestatin as well as acylated and des-acyl-ghrelin concentrations using ELISA. Bio-Plex inflammatory cytokine assays were used to profile expression of 17 inflammatory mediators, including IL-6, IL-7, IL-8, G-CSF, CCL2, and MIP-1??.

Results

Patients with NASH had twofold higher concentration of des-acyl-ghrelin than patients with non-NASH (2.58 vs. 1.24 pg/ml, P?P?P?P?=?0.014). Obestatin levels at baseline significantly correlated with rate of weight loss after bariatric surgery at various time points.

Conclusions

This study suggests that products of the GHRL gene may be important for the pathogenesis of NASH and fibrosis. Additional confirmatory studies are needed.  相似文献   
88.
The effect of domperidone (2 mg kg-1) on the pharmacokinetics of a single oral dose of theophylline (25 mg kg-1) was studied in the rat. Theophylline concentrations were measured serially for 12 h using an HPLC technique. Domperidone did not have any significant effect on any of the four parameters studied: peak plasma levels (Cpmax), the time these were attained (tmax), elimination half-life (t1/2) and area under the plasma concentration-time curve (AUC). Our data preliminarily suggests that domperidone may be safely coadministered with theophylline but clearly further studies in patients or relevant animal models of gastric motility disturbances are needed to reliably rule out any potential interaction between these agents.  相似文献   
89.
90.
We compared estrogen and/or ghrelin effects on pelvic floor muscles in old versus young adult ovariectomized rats. Ovariectomized Fisher 344 rats (18 and 3 months old, n = 24 x 2) received 42 daily intraperitoneal 17-beta estradiol (10 mug kg(-1)), ghrelin (2 mug kg(-1)), both, or vehicle (n = 6 x 4/group). Cytoplasmic p27(kip1) expression and isomyosin I proportion in striated urethral and anal sphincters and levator ani were measured, respectively, by Western blot analysis and gel electrophoresis with immunohistochemistry of muscle ghrelin receptors and radioimmunoassay of circulating growth hormone. In young adult rats, estrogen significantly decreased cytoplasmic p27(kip1) and isomyosin I signal intensities. In old rats, ghrelin and estrogen/ghrelin significantly decreased both intensities with greater estrogen/ghrelin effect. Ghrelin receptors were not immunostained in any muscle. Estrogen and/or ghrelin significantly increased or decreased, respectively, circulating growth hormone in old and young adult rats. Estrogen/ghrelin administration reversed pelvic floor muscle ageing changes in old ovariectomized rats through growth hormone production.  相似文献   
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