1,720,986 research outputs found
Actin-rich desmoplastic malignant melanoma: report of three cases
No full textWe report three cases of desmoplastic malignant melanoma (DMM) rich in smooth muscle actin. They occurred in two men (Cases 1 and 3) and in one woman (Case 2). Cases 1 and 2 were recurrent lesions from common melanomas excised, respectively, 3 and 1 years previously. In Case 3, DMM was associated with lentigo maligna at the time of presentation. Morphologically, DMMs were composed of spindle neoplastic cells organized in haphazardly orientated long fascicles separated by collagen bundles. Perineural invasion was present and mitotic activity was prominent in all cases. The neoplastic spindle cells were intensely positive with S100 protein and smooth muscle actin antisera and negative with HMB45 and Melan-A (Mart-1) antibodies. Double staining for smooth muscle actin and S100 protein revealed no definite coexpression of the two antigens. Follow-up was available for patients 1 and 2 who had local recurrences and are still alive. It is possible that actin rich elements differentiate toward mesenchymal elements, paralleling the phenotypic changes seen in sarcomatoid carcinomas. Therefore, multidirectional differentiation may explain the mesenchymal (sarcomatoid) differentiation of neoplastic melanocytes and may be responsible for the different biologic behavior of DMMs, which is closer to mesenchymal tumors than to conventional melanomas
Controllo di qualità in anatomia patologica: un'eperienza di 10 anni
No full textThe quality assurance scheme in use at the Section of Anatomic Pathology of the University of Bologna-Bellaria Hospital is described. Since 1992 a quality assurance (QA) scheme has been set up in this Institution. The scheme and results have been reported in this same Journal previously: here are reported the changes to the scheme that have intervened in the last four years. All data collected from January 1999 to December 2002 have been reviewed for monitoring the laboratory performance. Emphasis has been given to changes that have been introduced recently to improve QA
Duodenal gangliocytic paraganglioma. Case report with immunohistochemical study on the expression of keratin polypeptides.
No full textA case of duodenal gangliocytic paraganglioma is described and the expression of keratin polypeptides is discussed
Histoplasma capsulatum var. capsulatum occurring in an HIV-positive Ghanaian immigrant to Italy - Identification of H-capsulatum DNA by PCR from paraffin sample
No full textHistoplasmosis, which is highly endemic in the United States, is rare in Europe, usually imported but sometimes autochthonous. In Africa, histoplasmosis capsulati coexists with African histoplasmosis, a characteristic skin infection caused by H. capsulatum var. duboisii. Histoplamosis due to H. capsulatum is one of the 12 secondary infections listed in the surveillance definitions of AIDS. We report the case of a 36-year-old black man with acquired immunodeficiency syndrome (AIDS) who was living in Italy but originally came from Ghana. Histoplasmosis was disseminated with fever and cutaneous manifestations. The diagnosis was demonstrated morphologically based on the presence of yeast, observed by light microscopy, in skin lesions and by identification of H. capsulatum var. capsulatum DNA by nested PCR from a paraffin sample. No clinical reports of histoplamosis capsulati in Ghana have been published until now. The present case stresses the role of immigration of subjects from outside Europe who have been infected in their native country
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Extra-axial chordoma. Report of a case with immunohistochemical study.
No full textA case of extra-axial chordoma arisen in the soft tissues of the posterior thoracic wall is reported. Immunohistochemistry showed coexpression of low molecular weight keratins, vimentin and S-100 protein in neoplastic cells. Although rare, examples of chordomas developing in extra-axial locations are reported in the literature and need be differentiated from other tumors that can mimic their histopathological features, such as myxoid chondrosarcomas
Expression of MHC class I and class II antigens in primary breast carcinomas and synchronous nodal metastases
No full textExpression of the major histocompatibility (MHC) class I and class II antigens was studied by immunohistochemistry in a series of 70 primary breast carcinomas and in nodal metastases, In particular, the expression of class I (HLA A-B-C) and class II (DP, DQ and DR) molecules was compared in: a) primary breast cancers devoid of nodal metastases (n = 36) and tumors exhibiting metastatic deposits (n = 34) at the time of surgery, and b) primary breast carcinomas and their corresponding synchronous axillary nodal metastases, Reduced or absent HLA A-B-C antigen expression was seen in approximately 54.3% of primary breast carcinomas, whereas a partial or complete induction of class II products was observed in 18.5% (DQ), 30% (DP) or 48.5% (DR) of the same cases, An almost complete overlap of antigen expression was observed in breast tumors in which no metastases were found by histological examination of axillary nodes and in neoplasms showing histologically-diagnosed synchronous metastases, The reactivity for class I and class II antigens in nodal metastases roughly paralleled that exhibited by corresponding primary tumors, A discordant expression was seen in 11 cases (32%) stained for HLA A-B-C and in 8 (24%), 7 (21%) and 6 (18%) cases assayed for DP, DQ and DR products, respectively, When a discordant expression was detected, either decreased or increased staining patterns were observed in metastases, The finding of overlapping MHC antigenic profiles in the majority of primary breast tumors and nodal metastases casts doubts on the hypothesis that loss of MHC antigens can play an important role in the seeding and growth of metastatic breast carcinoma cells
Myxoid metastases of melanoma: report of three cases and review of the literature
No full textWe report three cases of melanoma whose metastases to skin and regional lymph nodes showed myxoid foci, findings absent in their cutaneous primary tumors
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