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991.
Velazquez EF Barreto JE Rodriguez I Piris A Cubilla AL 《International journal of surgical pathology》2004,12(2):139-146
Surgeons often perform small or superficial penile biopsies that are difficult to classify definitely with regard to a benign or malignant nature, and if malignant, cannot always be accurately subclassified. Staging and therapeutic decisions rely on the identification, in these materials, of pathologic parameters related to prognosis. In this study, we evaluated the accuracy and completeness of pathologic information obtained from biopsies of 57 consecutive patients with squamous cell carcinoma (SSC) of the penis, and compared it with the information obtained from penectomies. Diagnostic accuracy was determined by recording discordances of critical factors in biopsies and penectomies. The evaluated parameters were as follows: cancer diagnosis, histologic type, tumor grade, depth of invasion (anatomical levels), and vascular invasion. Histologic subtypes of SCC were the following: usual 37, verruciform 11, mixed 7, pseudohyperplastic 1, and sarcomatoid 1. Grades were 1, 2, and 3 (well, moderately and poorly differentiated). Levels of invasion were lamina propria, corpus spongiosum, and corpus cavernosum in the glans; and lamina propria, dartos, and skin in the foreskin. In 2 patients with well-differentiated tumors a diagnosis of cancer could not be established in biopsy material. In 17 cases (30%) there was a biopsy-penectomy discordance of histologic types, especially of verruciform and mixed carcinomas. Biopsies failed to identify the correct histologic grade in 30% of the cases. A higher grade was usually identified in penectomy specimens. Because biopsies were superficial, the deepest point of invasion could not be determined in 91% of the cases. Vascular invasion was identified in biopsies in only 1 of 8 patients. In summary, biopsies were useful for cancer diagnosis except in 2 differentiated variants of penile squamous cell carcinoma. However, important pathologic parameters related to prognosis were missed on biopsy materials, and they were more accurately evaluated in penectomy specimens. We conclude that clinical and pathologic staging of penile cancer, at least in our material, cannot depend on biopsy information alone. Data from biopsies may be insufficient to make a decision whether to perform a groin dissection, or for prognostic evaluation in those patients in whom other treatment modalities (such as radiotherapy or chemotherapy) are being considered. 相似文献
992.
Nardelli DT Burchill MA England DM Torrealba J Callister SM Schell RF 《Clinical and diagnostic laboratory immunology》2004,11(6):1075-1084
CD4+ CD25+ T cells are a population of regulatory T cells responsible for active suppression of autoimmunity. Specifically, CD4+ CD25+ T cells have been shown to prevent insulin-dependent diabetes mellitus, inflammatory bowel disease, and pancreatitis. Here, we present evidence that CD4+ CD25+ T cells also play a major role in controlling the severity of arthritis detected in Borrelia burgdorferi-vaccinated gamma interferon-deficient (IFN-gamma degrees ) C57BL/6 mice challenged with the Lyme spirochete. When B. burgdorferi-vaccinated and challenged IFN-gamma degrees mice were treated with anti-interleukin-17 (IL-17) antibody, the number of CD4+ CD25+ T cells increased in the local lymph nodes. Furthermore, histopathologic examination showed the mice to be free of destructive arthritis. When these anti-IL-17-treated B. burgdorferi-vaccinated and challenged mice were also administered anti-CD25 antibody, the number of CD4+ CD25+ T cells in the local lymph nodes decreased. More importantly, severe destructive arthropathy was induced. In addition, delayed administration of anti-CD25 antibody decreased the severity of the arthritis. These results suggest that CD4+ CD25+ T cells are involved in regulation of a severe destructive arthritis induced with an experimental model of vaccination and challenge with B. burgdorferi. 相似文献
993.
Respiratory syncytial virus and other pneumoviruses: a review of the international symposium--RSV 2003 总被引:3,自引:0,他引:3
Schmidt AC Johnson TR Openshaw PJ Braciale TJ Falsey AR Anderson LJ Wertz GW Groothuis JR Prince GA Melero JA Graham BS 《Virus research》2004,106(1):1-13
The Respiratory Syncytial Virus 2003 symposium took place from 8th-11th November 2003 in Stone Mountain, Georgia, and brought together more than 200 international investigators engaged in RSV research. RSV biology, pathogenesis, and clinical data, as well as RSV vaccines and antivirals, were addressed in the meeting, and this review will aim to briefly summarize and discuss the implications of new findings. The meeting also served as the inauguration of the Robert M. Chanock Award for lifetime achievement in RSV research, an award named in honor of the person who started the field of RSV research by recovering the first human RS virus from infants with severe bronchiolitis in 1956. 相似文献
994.
Role of tau protein in both physiological and pathological conditions 总被引:21,自引:0,他引:21
The morphology of a neuron is determined by its cytoskeletal scaffolding. Thus proteins that associate with the principal cytoskeletal components such as the microtubules have a strong influence on both the morphology and physiology of neurons. Tau is a microtubule-associated protein that stabilizes neuronal microtubules under normal physiological conditions. However, in certain pathological situations, tau protein may undergo modifications, mainly through phosphorylation, that can result in the generation of aberrant aggregates that are toxic to neurons. This process occurs in a number of neurological disorders collectively known as tauopathies, the most commonly recognized of which is Alzheimer's disease. The purpose of this review is to define the role of tau protein under normal physiological conditions and to highlight the role of the protein in different tauopathies. 相似文献
995.
Role of intrathyroidal calcifications detected on ultrasound as a marker of malignancy 总被引:15,自引:0,他引:15
OBJECTIVES: Clinically palpable thyroid nodules are present in between 4% and 7% of the population, with only a small percentage of those harboring malignancy. Thus, it is important to find a cost-effective way to determine which nodules are more likely to be malignant. The purpose of this study was to evaluate the use of intrathyroidal calcifications detected on ultrasound as a risk factor for malignancy. STUDY DESIGN: Retrospective chart review. METHODS: One hundred fifty-nine patients with thyroid disease were included in this study. Patients were selected from a thyroid ultrasound (TUS) database. Charts were then reviewed, and only those patients who had a preoperative TUS and underwent surgery for tissue diagnosis were included. RESULTS: Of the 159 patients, 66 (41.5%) were diagnosed with cancer. Of those with malignancy, 52 (78.8%) had calcifications noted on TUS. Ninety-three of the patients were diagnosed with benign pathology. Of those 93 patients, 36 (38.7%) had TUS findings consistent with calcifications, whereas 57 (61.3%) did not. Statistical analysis using a chi-square test showed a strong association between cancer status and calcification, with P <.001. In our study, calcifications on TUS had a sensitivity of 78.8% and a specificity of 61.3%, with an odds ratio of 5.88. CONCLUSION: The presence of calcifications detected on TUS should alert the physician for the possibility of malignancy, and further work-up should be pursued. This information may be used to improve the sensitivity of other diagnostic tests such as fine needle aspiration biopsies. Given the relatively low sensitivity and specificity of the test, its use alone as a marker of malignancy is limited, but it may be used in combination with other known risk factors and tests to decide on the most appropriate treatment plan. 相似文献
996.
Otero-Garcia JE Youssef E Enamorado II Du W Yoo GH Merati K Kewson D Lonardo F Jacobs JR Kim H 《American journal of otolaryngology》2004,25(4):231-239
OBJECTIVE: To determine the prognostic significance of p53 and fragile histidine triad (FHIT) expression in advanced oropharyngeal squamous cell carcinoma. STUDY DESIGN: A retrospective collection of clinical data was correlated with the protein expression. METHOD: The expression of p53 and FHIT in specimens from patients with previously untreated advanced squamous cell carcinoma of the oropharynx was determined by immunohistochemistry. The expression of p53 and FHIT was statistically correlated with survival outcome. The primary endpoints were overall survival and disease-free survival. RESULTS: Thirty-four patients were analyzed in this study. Overexpression of p53 was observed in 41.2% (14/34) of tumors and was associated with a trend toward an improved overall survival using univariate (P =.1088, risk ratio [RR] = 0.503) and multivariate (P =.1533, RR = 0.470) analyses. Marked reduction or complete absence of FHIT expression was observed in 57.6% (19/33) of tumors. Patients with tumors showing no reduction in FHIT expression had a lower overall survival using univariate (P =.04, RR = 2.27) and multivariate (P =.013, RR = 4.41) analyses. CONCLUSION: Overexpression of p53 predicted a trend toward an improved prognosis, whereas no reduction in FHIT expression predicted a significantly poorer outcome in patients with advanced oropharyngeal cancer. 相似文献
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