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51.
p16 overexpression identifies HPV-positive vulvar squamous cell carcinomas   总被引:3,自引:0,他引:3  
Two types of vulvar squamous cell carcinomas (VSCCs) are recognized according to their relationship to human papillomavirus (HPV). Basaloid or warty carcinomas are considered HPV-associated tumors, whereas differentiated keratinizing neoplasms are considered non-HPV-associated. Recently, immunohistochemical detection of p16 and p53 has been proposed to differentiate these 2 types of VSCCs. We conducted a histologic study with immunohistochemical evaluation of p16 and p53 and HPV detection and typing by polymerase chain reaction using 2 different sets of primers in 92 cases of VSCCs to evaluate the usefulness of immunohistochemistry in the classification of VSCCs and to describe the clinico-pathologic characteristics of both types of VSCCs. HPV was detected in 16/92 (17.4%) specimens, HPV16 being identified in 75% of positive cases. A significant number of discrepancies between histology and HPV detection were observed, with 37.5% of HPV-positive tumors being keratinizing and 9.2% of HPV-negative carcinomas showing basaloid or warty features. Diffuse positivity for p16 and p53 was observed in 100% and 6.2% of HPV-positive tumors and in 2.3% and 64.5% of HPV-negative neoplasms, respectively. The sensitivity and specificity of p16 immunostaining to detect HPV-associated carcinomas (100% and 98.7%, respectively) were better than those of histologic criteria (93.8% and 35.5%) and of p53 negative stain (62.5% and 93.4%). Vulvar intraepithelial neoplasia grade 3 of basaloid/warty type was identified in 53.8% HPV-positive tumors, including 3 keratinizing tumors. All these cases were p16 positive and p53 negative. Vulvar intraepithelial neoplasia grade 3 of differentiated type was observed in 45.6% of HPV-negative cases; 90.8% of them were positive for p53 but all were negative for p16. No differences in age, stage, or development of recurrence were observed between HPV-positive and negative tumors. In summary, the current morphologic criteria to discriminate HPV-positive and negative VSCCs have a significant overlap. Immunostaining for p16 is a reliable marker for HPV-positive VSSCs, which improves the results of histologic classification.  相似文献   
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BACKGROUND: Paraganglioma (PGL) and phaeochromocytoma (PCC) are chemotherapy and radiation-resistant neuroendocrine tumors that arise from sympathetic tissue, and rarely occur in children. PCC may be associated with predisposing (germline) conditions like the multiple endocrine neoplasia type 2 (MEN2; OMIM 164761), von Hippel-Lindau syndrome (VHL; OMIM 193300), and rarely neurofibromatosis type 1 syndrome (NF1; OMIM 162200) and multiple endocrine neoplasia type 1 (MEN1; OMIM 131100). PGL, on the other hand, may be related to predisposing germline conditions like the familial PGL syndrome and the NF1 syndrome. In adult studies, one of the highest predisposing factors for germline mutation among patients presenting apparently sporadic PCC/PGL was their age at presentation. The aim of this study was to determine the rate of germline mutations among the rare patients presenting with sporadic PGL during childhood. PROCEDURE: In this study, we report the genetic analysis for predisposing conditions for the only three PGL cases retrospectively identified at our pediatric institution in the last 20 years. RESULTS: None had NF1 clinical associated lesions. Mutation screening of genes associated to VHL (VHL), MEN (RET), and familial PGL (SDH-B, -C, and -D) showed that all cases had germline deletions in the SDHB gene. We report a novel mutation, c.778 del C. Importantly, several non-symptomatic relatives were found to be carriers, thus ensuring them a clinical follow-up. CONCLUSION: According to our findings, PGL presenting during childhood represents an early manifestation of an adult disease caused by predisposing germline mutations. These results underline the importance of genetic studies in pediatric PGLs.  相似文献   
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BACKGROUND: There are two promising methods to assess cardiovascular risk: the Adult Treatment Panel III (ATPIII) and the Systematic Coronary Risk Evaluation (SCORE). The ATPIII calculates the 10-year risk of coronary events based on an adaptation of the original Framingham function. The SCORE chart is based on European studies and measures the absolute risk of cardiovascular mortality in the next 10 years. OBJECTIVE: To evaluate the clinical consequences of using different methods to calculate cardiovascular risk and different primary prevention guidelines. METHODS: A cross sectional study of 914 dyslipidemic patients from three primary health centres from Catalonia, Spain, was conducted. Outcome variables were the risk level according to the different equations (classical Framingham table by Anderson, ATPIII adapted Framingham table, and SCORE system), and candidates for lipid lowering treatment according to European and ATPIII guidelines. RESULTS: The proportion of high-risk patients according to the three equations and excluding diabetic patients was 13.5%, 11.4% and 7.1%, respectively, and 20.2%, 25.7% and 29.2%, respectively when including diabetic patients. The prevalence of candidates for lipid lowering treatment according to European guidelines and ATPIII guidelines were 28.8% and 39.3%, respectively. A 49% disagreement with a Kappa of -0.1, and a 37% disagreement with a Kappa of 0.08 were observed when comparing candidates identified for lipid lowering treatment and patients actually receiving that treatment, according to ATPIII and SCORE guidelines, respectively. CONCLUSION: Our results suggest important clinical and economic consequences when comparing European guidelines or ATPIII guidelines for the treatment of dyslipidemic patients in general practice.  相似文献   
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We hereby present a clinical case of a germinal tumour with a pulmonary and retroperitoneal dissemination in form of a great adenopathic mass that fistulizes into the duodenum, that obtained a complete resolution with chemotherapy.  相似文献   
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Background/ObjectivesTo analyze the ophthalmic characteristics of congenital prepapillary vascular loop (PVL) and to propose a new morphologic classification dividing the loops into six types.Subjects/MethodsCollaborative multinational multicentre retrospective study of PVL cases.ResultsThere was a total of 49 cases (61 eyes), 37 unilateral (75.5%) and 12 bilateral (24.5%), 32 arterial type (65.3%) and 18 venous type (36.7%) (one patient had either kind in each eye). The mean number of loops per eye was 2.7 (range, 1–7). The loops were asymptomatic in 42 cases (85.7%). Other findings included: the presence of cilioretinal artery (14 cases), retinal vascular tortuosity (26 cases), amaurosis fugax (1 case), branch retinal artery occlusion (1 case) and vitreous haemorrhage (3 cases). Six morphologic loop types could be discerned based on elevation (flat vs. elevated), shape (figure of 8 or corkscrew with hyaline sheath), number (multiple or single), location (central or peripheral), lumen size (arterial vs. arteriolar) and presence of vascular tortuosity or vitreous traction.ConclusionsPVL are usually asymptomatic and can be divided into six morphologic types with different pathogenesis during early embryogenesis.Subject terms: Anatomy, Physiology  相似文献   
59.
OBJECTIVES: To investigate the BH4 response in a group of patients with phenylketonuria (PKU) in order to offer this alternative treatment to the responsive patients. DESIGN AND METHODS: The 24-h-long Phe/BH4 loading test was performed on 64 PKU patients requiring dietary treatment. RESULTS: All patients with mild-PKU and 75% of patients with moderate-PKU were BH4 responsive, while only 11% of classic-PKU patients showed good/partial response (P < 0.0001). The percentages of Phe decrease after the BH4 loading test were significantly different in the three PKU phenotypes (mild PKU: 67.9 +/- 18.7; moderate PKU: 37.4 +/- 16.8; and classical PKU: 21.9 +/- 13.7; ANOVA with Bonferroni correction: P < 0.0001). We report four mutations (P147S, D222G, P275S, and P362T) not previously associated with BH4 responsiveness, all of them combined with mutations with zero predicted residual activity. CONCLUSION: Both the percentage of Phe decrease and the Phe value achieved 24 h after BH4 loading are valuable data in predicting a response. We report four mutations not previously associated with BH4 responsiveness.  相似文献   
60.
Shelton DL  Zeller J  Ho WH  Pons J  Rosenthal A 《Pain》2005,116(1-2):8-16
Pain and cachexia are two of the most debilitating aspects of rheumatoid arthritis. Despite that, the mechanisms by which they are mediated are not well understood. We provide evidence that nerve growth factor (NGF), a secreted regulatory protein that controls neuronal survival during development, is a key mediator of pain and weight loss in auto-immune arthritis. Function blocking antibodies to NGF completely reverse established pain in rats with fully developed arthritis despite continuing joint destruction and inflammation. Likewise, these antibodies reverse weight loss while not having any effect on levels of the pro-cachectic agent tumor necrosis factor (TNF). Taken together, these findings argue that pathological joint pain and joint destruction are mechanistically independent processes and that NGF regulates an alternative cachexia pathway that is independent or downstream of TNF.  相似文献   
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