Search results for "Histochemistry"
showing 10 items of 1604 documents
BDNF, but not NT-4, is necessary for normal development of Meissner corpuscles.
2005
Abstract Meissner corpuscles are rapidly adapting cutaneous mechanoreceptors depending for development on TrkB expressing sensory neurons, but it remains to be established which of the known TrkB ligands, BDNF or NT-4, is responsible of this dependence. In this study we analyze Meissner corpuscles in the digital pads of mice with target mutations in the genes encoding for either BDNF or NT-4, using immunohistochemistry and transmission-electron microscopy, and they were identified based on their morphology and expression of S100 protein. All wild-type animals as well as NT-4 −/− animals and BDNF and NT4 heterozygous animals have Meissner corpuscles that are normal in number and size. Howeve…
C-erbB-2-oncogene expression in breast carcinoma: Analysis by S1 nuclease protection assay and immunohistochemistry in relation to clinical parameters
1992
The c-erbB-2 mRNA was detected by the S1 nuclease protection assay and Northern blotting in breast cancer tissues. In contrast to the Northern blot analysis which has been used in all recent publications concerning c-erbB-2 expression on the level of RNA, the S1-nuclease protection assay has distinct advantages with respect to sensitivity, reproducibility, and handling of radioactive probes. We compared the expression of c-erbB-2 in 120 breast carcinomas which were operated in the years 1989-1990 on the level of the mRNA (S1 nuclease protection assay) and the protein (immunohistochemistry), respectively. In general, results obtained with both methods were in good agreement. Only minor diffe…
Immunohistochemical expression of Bcl-2 in benign and malignant salivary gland tumors
2010
Objectives: The present study was undertaken to assess and compare the immunohistochemical expression of Bcl-2 in selected benign and malignant salivary gland tumors. Study Design: A total of 50 cases of buffered formalin-fixed, paraffin embedded tissues of previously diagnosed cases of benign and malignant salivary gland tumors from the archives of Department of Oral and Maxillofacial Pathology and Microbiology, SDM College of Dental Sciences and Hospital, Dharwad, India, were taken for the study. The immunohistochemical staining procedure was performed using monoclonal anti Bcl-2 antibody, as directed by the manufacturer. Results: Thirty six cases (72%) out of 50 cases showed a positive e…
SOX2 and BCL-2 Expressions in Odontogenic Keratocyst and Ameloblastoma
2020
Background The purpose of this experimental study was to compare the immunohistochemical expression of SOX2 and BCL-2 in Odontogenic Keratocyst (OKC) and Ameloblastoma (AB) specimens, and to identify a possible correlation in their expression. Material and Methods Immunohistochemical analysis was performed to evaluate SOX2 and BCL-2 expression in OKC (n = 20) and AB (n = 20). The immunoexpression was analyzed by a quantitative and qualitative scoring system. The comparison between the immunoexpression of SOX 2 and BCL-2 was assessed by the Mann-Whitney U-test. Spearman’s correlation coefficient evaluated the correlation between SOX2 and BCL-2 expressions. Results SOX2 and BCL-2 expression w…
Papulo-purpuric dermatitis of childhood: a distinct PLEVA-like eruption associated to SARS-CoV-2 infection. Clinical, histopathological and immunohis…
2021
Abstract We observed ten children with a papular eruption with purpuric features during the SARS‐CoV‐2 pandemic in Northern Italy (May‐December 2020). Histological examination showed signs of SARS‐CoV‐2‐related dermatosis. Evidence of nucleocapsid viral proteins using SARS‐CoV‐2 (2019‐nCoV) nucleocapsid antibody revealed cuticular staining of the deep portion of the eccrine glands in all cases.
Plexiform Atypical Spitz Tumor With Rosette-Like Giant Cells. A Histologic and Immunohistochemical Study on a Case Suggesting Ganglioneuroblastic Dif…
2018
Spitz nevi, atypical Spitz tumors and Spitzoid melanoma, the three clinicopathologic forms that constitute the spectrum of the Spitz-type melanocytic lesions, share a histologic picture characterized by large spindle and/or epithelioid ganglion-like cells, with various admixtures of multinucleate bizarre cells. This remarkable cytology has always been interpreted as an unusual, as well as unexplained form of atypia. We report a case of atypical Spitz tumor with Homer Wright-like rosettes, a feature characteristic of ganglioneuroblastic proliferation. Furthermore, the ganglion-like cells of the tumor showed basophilic punctuation in the cytoplasm, reminiscent of Nissl substance, and a few ce…
Study of the immunophenotype of the inflammatory cells in melanomas with regression and halo nevi.
2015
Abstract The pathogenesis and prognostic implications of regression in melanoma are not well understood. It has traditionally been considered an immunologically mediated phenomenon. Improvement in the knowledge of the mechanisms that lead to regression may prove to be of great value in an era in which treatments oriented to the augmentation of the host's immunity against melanoma have demonstrated excellent clinical results. This study was designed to improve the understanding of the mechanisms underlying melanoma regression and the differences between similar situations in benign melanocytic nevus. The study sample consisted of 77 lesions: 62 melanomas and 15 halo nevi. The following marke…
Comparative expression of cyclooxygenase 2 and Ki67 in amelanotic and conventional oral melanomas
2020
Background Oral melanomas have some histopathological resemblance with its cutaneous counterpart; however, an aggressive behavior is more common in tumors that occur in the oral cavity. Several markers have been suggested as indicative of tumoral progression and aggressiveness, such as cyclooxygenase 2 (COX-2) and Ki67. Material and Methods In this study, we have compared the expression of COX-2 and Ki67 in a series of amelanotic (n=7) and melanotic oral melanomas (n=22). The cases were selected from 4 pathology laboratories and submitted to the immunohistochemical (IHC) reactions. We analyzed the IHC staining based on a qualitative – using visual scores; and a computer-assisted method (qua…
Primary cutaneous plasmacytosis in a child. Is this a new entity?
2002
Plasma cell proliferations represent a heterogeneous spectrum of disorders. A 7-year-old Caucasian female had suffered an asymptomatic eruption on the trunk for 4 years. Physical examination revealed a plaque with scattered red-brown papules and nodules. Chemical analysis revealed normal proteinaemia. Histological examination of biopsy specimens showed dense perivascular and periadnexal infiltrate, consisting largely of plasma cells, in the superficial and deep dermis. Immunohistochemical study showed that many cells of the infiltrate were CD20 positive. The plasma cells expressed kappa and lambda light chains. The girl's status (age; absence of hypergammaglobulinaemia, lymphadenopathy and …
Metallothionein immunoexpression in non-syndromic and syndromic keratocystic odontogenic tumour
2015
Background To compare the metallothionein (MT) immunoexpression in non-syndromic and syndromic keratocystic odontogenic tumour (KOT), to correlate MT with cellular proliferation, and to evaluate the influence of inflammation in MT. Material and Methods Fourteen cases of KOT were submitted to immunohistochemistry for MT and Ki-67 analysis. The lesions were grouped according to their grade of inflammation, and statistical analysis was performed. Results MT was higher in non-syndromic KOT than in syndromic KOT (p<0.05). No statistical difference in Ki-67 could be identified; however, an inverse correlation was observed between MT and Ki-67 in both lesions. When analysing inflammation, non-synd…