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L.J. Mackintosh† M.N.C. de Koning‡ W.G.V. Quint‡ J. ter Schegget‡ I.M. Morgan R.M. Herd† M.S. Campo 《The British journal of dermatology》2009,161(1):56-62
Background Nonmelanoma skin cancer (NMSC) has been linked to cutaneous human papillomaviruses of the genus beta (betaPV).
Objectives We sought to assess the presence of betaPV in NMSC biopsies from a group of Scottish skin cancer patients, both immunocompetent (IC) patients and immunosuppressed (IS) organ transplant recipients.
Methods One hundred and twenty-one paraffin-embedded skin tumours (27 actinic keratosis, 41 intraepidermal carcinoma, 53 squamous cell carcinoma) and 11 normal skin samples were analysed for the presence of betaPV by a polymerase chain reaction–reverse hybridization assay designed to detect the presence of the 25 known betaPV genotypes.
Results In IC patients, betaPV was detected in 30 of 59 (51%) tumours and two of 11 (18%) normal skin samples ( P = 0·046). In IS patients, betaPV was found in 27 of 62 (44%) tumours; no normal skin samples were available for comparison. The most frequently found genotypes were HPV-24, HPV-15 and HPV-38. Of those tumours infected with betaPV, 28 of 57 (49%) were infected with more than one genotype (range 2–8). Tumours from IS patients were from a younger age group (mean age 57·4 years) than IC patients (mean age 73·8 years). Multiple infections were more common in tumours from IC patients (21 of 30; 70%) compared with those from IS patients (seven of 27; 26%) ( P < 0·001). In the IC group, age did not appear to influence the distribution of single and multiple infections whereas in IS patients the proportion of multiple infections to single infections increased with age. There were no multiple infections in normal skin.
Conclusions A wide spectrum of betaPV types was detected in our samples. Further characterization of betaPV in vivo is needed in order to determine the mechanisms by which the virus contributes to cutaneous carcinogenesis. 相似文献
Objectives We sought to assess the presence of betaPV in NMSC biopsies from a group of Scottish skin cancer patients, both immunocompetent (IC) patients and immunosuppressed (IS) organ transplant recipients.
Methods One hundred and twenty-one paraffin-embedded skin tumours (27 actinic keratosis, 41 intraepidermal carcinoma, 53 squamous cell carcinoma) and 11 normal skin samples were analysed for the presence of betaPV by a polymerase chain reaction–reverse hybridization assay designed to detect the presence of the 25 known betaPV genotypes.
Results In IC patients, betaPV was detected in 30 of 59 (51%) tumours and two of 11 (18%) normal skin samples ( P = 0·046). In IS patients, betaPV was found in 27 of 62 (44%) tumours; no normal skin samples were available for comparison. The most frequently found genotypes were HPV-24, HPV-15 and HPV-38. Of those tumours infected with betaPV, 28 of 57 (49%) were infected with more than one genotype (range 2–8). Tumours from IS patients were from a younger age group (mean age 57·4 years) than IC patients (mean age 73·8 years). Multiple infections were more common in tumours from IC patients (21 of 30; 70%) compared with those from IS patients (seven of 27; 26%) ( P < 0·001). In the IC group, age did not appear to influence the distribution of single and multiple infections whereas in IS patients the proportion of multiple infections to single infections increased with age. There were no multiple infections in normal skin.
Conclusions A wide spectrum of betaPV types was detected in our samples. Further characterization of betaPV in vivo is needed in order to determine the mechanisms by which the virus contributes to cutaneous carcinogenesis. 相似文献
995.
Kathryn Nichol Sean P. Deeny Joseph Seif Kevin Camaclang Carl W. Cotman 《Alzheimer's & dementia》2009,5(4):287-294
BackgroundHuman studies on exercise, cognition, and apolipoprotein E (APOE) genotype show that ε4 carriers may benefit from regular physical activity.MethodsWe examined voluntary wheel-running, memory, and hippocampal plasticity in APOE ε3 and APOE ε4 transgenic mice at 10–12 months of age.ResultsSedentary ε4 mice exhibited deficits in cognition on the radial-arm water maze (RAWM), a task dependent on the hippocampus. Six weeks of wheel-running in ε4 mice resulted in improvements on the RAWM to the level of ε3 mice. Hippocampal brain-derived neurotrophic factor (BDNF) levels were similar in ε3 and ε4 mice, and after exercise BDNF was similarly increased in both ε3 and ε4 mice. In sedentary ε4 mice, tyrosine kinase B (Trk B) receptors were reduced by 50%. Exercise restored Trk B in ε4 mice to the level of ε3 mice, and in ε4 mice, exercise dramatically increased synaptophysin, a marker of synaptic function.ConclusionsOur results support the hypothesis that exercise can improve cognitive function, particularly in ε4 carriers. 相似文献
996.
自制32P敷贴器治疗瘢痕疙瘩 总被引:1,自引:0,他引:1
目的:观察自制32P敷贴器局部敷贴治疗不同类型瘢痕疙瘩的临床疗效。
方法:105例瘢痕疙瘩患者中,39例病变厚度≤ 0.3 cm的行单纯敷贴治疗,病变厚度> 0.3 cm的66例随机分为2组,单纯敷贴组36例,手术+敷贴组30例。单纯敷贴根据病变表面积大小及形状剪取敷贴片,根据剂量率和衰变校正计算每天敷贴时间,直接贴于病变表面,每天4.0~5.0 Gy/(部位•次),连续4 d为一疗程,每疗程间隔4周,总治疗4~6个疗程。幼儿单次剂量控制在每天4 Gy/(部位•次)以下。手术+敷贴组患者手术切除瘢痕疙瘩,待手术伤口无渗出后根据伤口形状剪取敷贴片对准伤口敷贴,剂量及疗程同单纯敷贴组。
结果:单纯敷贴治疗对病变厚度≤0.3 cm的39例瘢痕疙瘩治愈32例(82%),总有效率98%;对病变厚度> 0.3 cm的瘢痕疙瘩单纯敷贴和手术+敷贴两组治疗总有效率分别为56%和93% ,两组差异有显著性意义(P < 0.01),其中病程< 9个月的患者治疗有效率分别为25%和75%,病程较长患者治疗有效率分别为13%和77%。治疗过程中有26例在敷帖过程中出现局部皮肤烧灼和刺痛感,均以炉甘石洗剂局部外用处理后缓解;5例出现Ⅰ度放射性皮炎,2例出现Ⅱ度放射性皮炎,以百多邦软膏局部外用后缓解,无出现Ⅲ度以上放射性皮炎病例。治愈患者局部皮肤均有不同程度的色素沉着或皮肤颜色改变。
结论:32P敷贴治疗瘢痕疙瘩治疗安全有效,对病程较短或病变厚度小于0.3 cm的患者可单纯敷贴治疗,病程较长或病变厚度大于0.3 cm患者建议先手术后再敷贴治疗。 相似文献
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The recent development of brain atlases with computer graphics templates, and of huge databases of neurohistochemical data on the internet, has forced a systematic re-examination of errors associated with comparing histological features between adjacent sections of the same brain, between brains treated in the same way, and between brains from groups treated in different ways. The long-term goal is to compare as accurately as possible a broad array of data from experimental brains within the framework of reference atlases. Main sources of error, each of which ideally should be measured and minimized, include intrinsic biological variation, linear and nonlinear distortion of histological sections, plane of section differences between each brain, section alignment problems, and sampling errors. These variables are discussed, along with approaches to error estimation and minimization in terms of a specific example—the distribution of neuroendocrine neurons in the rat paraventricular nucleus. Based on the strategy developed here, the main conclusion is that the best long-term solution is a high-resolution 3D computer graphics model of the brain that can be sliced in any plane and used as the framework for quantitative neuroanatomy, databases, knowledge management systems, and structure–function modeling. However, any approach to the automatic annotation of neuroanatomical data—relating its spatial distribution to a reference atlas—should deal systematically with these sources of error, which reduce localization reliability. 相似文献
999.
Paul H. Lysaker Louanne W. Davis Gary J. Bryson Morris D. Bell 《Schizophrenia Research》2009,107(2-3):186-191
Designed to help persons with schizophrenia to persist and perform better at job placements, the Indianapolis Vocational Intervention Program (IVIP) is a program of cognitive-behavioral group and individual interventions. While its feasibility has been previously demonstrated, it is unknown whether IVIP assists persons to achieve greater levels of participation in vocational rehabilitation and higher levels of job performance. In this study, 100 participants with schizophrenia or schizoaffective disorder were offered a six month job placement and randomized to receive IVIP (n = 50) or support services (n = 50) matched for treatment intensity. Number of hours worked was recorded weekly and job performance was assessed biweekly using the Work Behavior Inventory with raters blind to condition. t-tests revealed that participants in the IVIP group worked a significantly greater number of weeks than those in the support condition. Also, repeated measures ANOVA revealed the IVIP group worked more hours across that 26 week period as well. And with regards to work performance, repeated measures of the 56 participants who worked for at least two-thirds of the intervention revealed that participants in the IVIP group had generally better work performance than those in the support condition. Results suggest a connection between cognitive-behavioral interventions and higher levels of work performance in people with schizophrenia. 相似文献
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