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Aetiological factors for oral manifestations of HIV   总被引:2,自引:0,他引:2  
OBJECTIVES: Describe the oral diseases in HIV-infected individuals in London, UK and identify social and medical factors related to the presence of specific oral diseases.
DESIGN: Cross-sectional analytic study.
SETTING: Dental clinics.
SUBJECTS: Consecutive sample of 456 patients with HIV infection.
METHODS: Social and medical history and clinical examinations. Univariate and logistic regression analysis.
OUTCOMES: Presence of HIV-associated oral disease.
RESULTS: 80% of patients with AIDS and 50% of patients with HIV had a specific oral disease. The most common diseases were hairy leukoplakia (30%), erythematous candidiasis (24%), pseudomembranous candidiasis (14%), angular chielitis (6%), necrotising periodontal disease (8%) and non-recurrent ulceration (6%).
CONCLUSIONS: The presence of erythematous candidiasis was not related to advanced HIV disease. Pseudomembranous candidiasis, hairy leukoplakia and mucosal ulceration were significantly associated with advanced HIV disease. Smoking was also identified as a strong aetiological factor in oral diseases. Longitudinal studies are required to further explore the prognostic significance of oral diseases in HIV infection.  相似文献   
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Introduction

The median survival of patients with glioblastoma multiforme (astrocytoma grade 4) remains less than 18 months despite radical surgery, radiotherapy and systemic chemotherapy. Surgical implantation of chemotherapy eluting wafers into the resection cavity has been shown to improve length of survival but the current licensed therapy has several drawbacks. This paper investigates in vivo efficacy of a novel drug eluting paste in glioblastoma.

Methods

Poly(lactic-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) self-sintering paste was loaded with the chemotherapeutic agent etoposide and delivered surgically into partially resected tumours in a flank murine glioblastoma xenograft model.

Results

Surgical delivery of the paste was successful and practical, with no toxicity or surgical morbidity to the animals. The paste was retained in the tumour cavity, and preliminary results suggest a useful antitumour and antiangiogenic effect, particularly at higher doses. Bioluminescent imaging was not affected significantly by the presence of the paste in the tumour.

Conclusions

Chemotherapy loaded PLGA/PEG paste seems to be a promising technology capable of delivering active drugs into partially resected tumours. The preliminary results of this study suggest efficacy with no toxicity and will lead to larger scale efficacy studies in orthotopic glioblastoma models.  相似文献   
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Background: Long QT syndrome (LQTS) is a potentially lethal cardiac channelopathy that affects one in 2,000 persons; causes syncope, seizures, and sudden death; and is both under‐ and overdiagnosed. LQTS diagnostic miscues have stemmed from assessment of ambulatory electrocardiographic monitoring (Holter) results. Objective: We sought to determine the prevalence of positive Holter monitor tests and its diagnostic significance in evaluating LQTS. Methods: We performed an institutional review board‐approved review of patients evaluated in our LQTS clinic from 2000 to 2009 who had Holter testing during their evaluation. Included patients (N = 473) were diagnosed with LQTS or dismissed as otherwise normal. Holters classified as positive had an episode of nonsustained ventricular tachycardia, supraventricular tachycardia, ≥4 couplets/day, ≥10 premature ventricular contractions/hour, or >5‐second sinus pause. Results: Among 209 patients dismissed as normal (128 females, average age 21 ± 15 years, average QTc 424 ± 39 ms), 27 (12.9%) had a positive Holter, while among 264 patients with LQTS (149 females, average age 22 ± 16 years, average QTc 472 ± 41 ms), 30 (11.3%) had a positive Holter (P = NS). Patients with LQT3 (5/23, 21%) and genotype‐negative LQTS (5/19, 26%) had a higher rate of positive Holter testing compared to LQT1 patients (7/124, 6%, P < 0.03). Among the 473 Holters, only one (0.2%) impacted clinical decision making. Conclusion: Routine Holter monitoring appears to be of minimal clinical utility from a diagnostic and prognostic perspective in evaluating LQTS, and may not be cost effective. Whether Holter monitoring aids in therapeutic decisions such as dosing or whether ambulatory QTc measurements, provided by some newer devices, might help in the diagnostic evaluation warrants further scrutiny. (PACE 2011; 34:1100–1104)  相似文献   
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OBJECTIVE: To perform a molecular autopsy involving the RyR2-encoded cardiac ryanodine receptor/calcium release channel to determine whether mutations responsible for catecholaminergic polymorphic ventricular tachycardia (CPVT) represent a novel pathogenic basis for unexplained drownings. METHODS: A cardiac channel molecular autopsy was performed on 2 individuals who died of unexplained drowning and whose cases were referred to the Sudden Death Genomics Laboratory at the Mayo Clinic in Rochester, Minn. Comprehensive mutational analysis of all 60 protein-encoded exons of the 5 long QT syndrome-causing cardiac channel genes and a targeted analysis of 18 RyR2 exons known to host RyR2-mediated CPVT-causing mutations (CPVT1) was performed using polymerase chain reaction, denaturing high-performance liquid chromatography, and DNA sequencing. RESULTS: Both individuals harbored novel mutations in RyR2. Postmortem mutational analysis revealed a familial missense mutation in exon 14, R414C, in a 16-year-old girl. A 9-year-old boy possessed a sporadic missense mutation in exon 49, V2475F. Both amino acid positions involve highly conserved residues that localize to critical functional domains in the calcium release channel. Neither substitution was present in 1000 reference alleles. CONCLUSIONS: This molecular autopsy study provides proof of principle that RyR2 mutations can underlie some unexplained drownings. A population-based genetic epidemiology study that involves molecular autopsies of individuals who die of unexplained drowning is needed to determine the prevalence and spectrum of KCNQ1 and now RyR2 mutations as potential pathogenic mechanisms for drowning.  相似文献   
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膈下逐瘀汤对肝癌Bel-7402细胞增殖的抑制及其机制   总被引:1,自引:0,他引:1  
目的:观察中药复方膈下逐瘀汤对肝癌Bel-7402细胞增殖的抑制及其相关机制。方法:实验于2005-09/2006-07在南方医科大学细胞生物实验室完成。膈下逐瘀汤(按《医林改错》方组成:五灵脂6g,当归9g,川芎6g,桃仁9g,丹皮6g,赤芍6g,乌药6g,延胡索3g,甘草9g,香附5g,红花9g,枳壳5g。均购自南方医院中药房)经研粉、煮沸、离心、过滤配成质量浓度为25,50,100,200mg/L的药液;顺铂配制成质量浓度为0.5,1.0,1.5,2.0mg/L的药液(作为阳性对照),均作用于Bel-7402细胞,并设空白对照(未加任何药物)。采用甲基噻唑基四唑(methyl thiazoly ltetrazolium,MTT)比色法检测膈下逐瘀汤各组对Bel-7402细胞生长的影响,用酶标仪测定培养细胞在600nm处吸光度值,并计算细胞抑制率,抑制率(%)=(实验组吸光度值-对照组吸光度值/对照组吸光度值)×100%。用蛋白印迹试验检测不同质量浓度药物作用48,72h时第10号染色体同源丢失性磷酸酶-张力蛋白基因蛋白的表达水平。结果:①中药复方膈下逐瘀汤对Bel-7402细胞增殖的影响:膈下逐瘀汤对肝癌Bel-7402细胞有明显的生长抑制作用,呈良好的剂量-效应关系。膈下逐瘀汤质量浓度在200mg/L时其48h细胞生长抑制率介于0.5mg/L顺铂组与1.0mg/L顺铂组之间(分别为41.27%,34.01%,47.49%);膈下逐瘀汤质量浓度在50,25mg/L时,其细胞抑制率明显低于顺铂组,72h细胞抑制率结果基本相同。②药物作用肝癌Bel-7402细胞48h后第10号染色体同源丢失性磷酸酶-张力蛋白基因蛋白的表达:第10号染色体同源丢失性磷酸酶-张力蛋白基因蛋白的表达增多,200mg/L膈下逐瘀汤组介于0.5mg/L顺铂组和1.0mg/L顺铂组之间。结论:中药复方膈下逐瘀汤抑制Bel-7402细胞的增殖机制可能是第10号染色体同源丢失性磷酸酶-张力蛋白基因表达增多的原因。  相似文献   
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