E-cadherin immunoexpression patterns in the characterisation of gastric carcinoma histotypes.

AIMS: E-cadherin, the main epithelial intercellular adhesion molecule, is abnormally expressed in many cancer types, including gastric carcinoma, which is the second leading cause of cancer death worldwide. The aim of this study was to contribute to the characterisation of gastric carcinoma histotypes based on a new approach to E-cadherin immunoexpression. METHODS: 97 gastric tumour samples obtained from the files of the Hospital of Cancer/Cancer Institute of Ceará, Brazil, were histologically analysed and classified as intestinal (n=40), diffuse (n=34), mixed (n=16) or unclassified (n=7) carcinomas. Immunohistochemistry was performed on the tissue microarray sections. Scores were applied according to the system of Jawhari: 0, no staining; 1, cytoplasmic staining; 2, cytoplasmic and membranous staining in the same case; 3, normal membranous immunoexpression; abnormal patterns: scores 0, 1 and 2; normal pattern: score 3. Jawhari scores were then evaluated utilising another approach: the absence of membranous expression scores (0 and 1) versus the presence of membranous expression (scores 2 and 3). RESULTS: A significant association between membranous expression of E-cadherin and the intestinal histotype (36/40 (90%), and 28/41 (68%) for other histotypes) was found, while diffuse carcinomas were related to the absence of membranous expression. A very strong and peculiar relationship was observed between cytoplasm-exclusive E-cadherin expression (score 1) and the diffuse component of mixed tumours (11/16 (69%)). CONCLUSIONS: E-cadherin immunoexpression patterns help us to characterise gastric carcinoma histotypes. The presence or absence of membranous staining is the most valuable criterion in evaluating E-cadherin expression. Mixed tumours show a characteristic E-cadherin cytoplasmic expression in gastric carcinomas.

Bone marrow fibrosis (pseudo-myelofibrosis) in human kala-azar.

Thirty cases of human kala-azar were diagnosed by iliac crest biopsy and myeloculture. Histological analysis of 12 patients showed diffuse thickening of reticulin fibers. To the best of our knowledge, this is the third report describing secondary bone marrow fibrosis (myelofibrosis-like) associated with kala-azar. Patients with positive bone marrow fibrosis (pbmf = 12) were compared to patients without detectable bone marrow fibrosis (wbmf = 18). There were no significant differences in clinical and blood parameters following treatment. All patients showed regression of hepatosplenomegaly. Our findings suggest that associated bone marrow fibrosis is transient and did not interfere in the evolution of treated patients.

Analise antigenica de diferentes cepas do Trypanosoma cruzi. / Antigenic analysis of various strains of Trypanosoma cruzi

Foi feita analise imunoeletroforetica dos extratos antigenicos de tres diferentes cepas do Trypanosoma cruzi que, pelos seus caracteres morfobiologicos e histopatologicos, representam os prototipos de tres diferentes tipos de cepas: Tipos I (cepa Peruana), II (12SF) e III (Colombiana). A analise foi feita contra soros hiper-imunes obtidos em coelhos sensibilizados com os mesmos antigenos, de mistura com o Adjuvante de Freund. A analise de cada antigeno foi feita contra o antissoro homologo (obtido pela sensibilizacao com a mesma cepa) e contra os antissoros heterologos. Verificou-se para cada cepa estudada, nitidas diferencas do padrao imunoeletroforetico em relacao ao numero, distribuicao e intensidade das linhas de precipitacao.Os soros anti-Peruana e anti-12SF quando reagiram com os antigenos heterologos mantiveram o mesmo padrao observado em sua reacao com o antigeno homologo. O soro anti-Colombiana, entretanto, mostrou padroes diferentes quando reagiu com os antigenos heterologos. Os resultados sugerem que existem componentes comuns nas tres cepas, que diferem quanto a sua imunogenicidade e que a cepa Colombiana tem, alem disto, componentes proprios, que diferem das demais. Parece interessante a verificacao de que cepas de diferentes tipos tambem diferem quanto aos seus componentes antigenicos