Pan-cytokeratin immunoexpression in Wilms' tumors: a simple approach for understanding tumor epithelial differentiation

Wilms' tumor is one of the most common solid tumors in children and is an interesting model for understanding the pathogenesis of embryonal tumors. Cytokeratins are intracellular fibrous proteins present in tissue of epithelial origin. The immunoexpression of the pan-cytokeratin AE1AE3 was studied in paraffin-embedded tissue sections from 24 Wilms' tumors (12 with nephrogenic rests) and also tissue samples from 15 corresponding normal kidneys, to evaluate epithelial differentiation in the genesis of Wilms' tumor. We observed that the intensity of the expression of AE1AE3 in the epithelial component of Wilms' tumors directly correlated with the degree of maturity of the epithelial structures correspondent to the collecting ducts

Use of a new fibrin sealant and laser irradiation in the repair of skull defects in rats

This study evaluated the osteogenic capacity of a new fibrin sealant (FS) combined with bone graft and laser irradiation in the bone repair. Defects were created in the skull of 30 rats and filled with autogenous graft and FS derived from snake venom. Immediately after implantation, low-power laser was applied on the surgical site. The animals were divided in: control group with autogenous graft (G1), autogenous graft and laser 5 J/cm2 (G2), autogenous graft and laser 7 J/cm2 (G3), autogenous graft and FS (G4), autogenous graft, FS and laser 5 J/cm2 (G5), autogenous graft, FS and laser 7 J/cm2 (G6). The animals were sacrificed 6 weeks after implant. Results showed absence of inflammatory infiltrate in the bone defect. New bone formation occurred in all groups, but it was most intense in G6. Thus, the FS and laser 7 J/cm2 showed osteoconductive capacity and can be an interesting resource to be applied in surgery of bone reconstruction.Este estudo avaliou a capacidade osteogênica de um novo selante de fibrina (FS) associado com enxerto ósseo e irradiação laser no reparo ósseo. Defeitos foram criados no crânio de 30 ratos e preenchidos com enxerto autógeno e FS derivado do veneno de cobra. Imediatamente após implantação, foi aplicado laser de baixa potência na área cirúrgica. Os animais foram divididos em grupo controle com autógeno (G1), autógeno e laser 5 J/cm2 (G2), autógeno e laser 7J/cm2 (G3), autógeno e FS (G4), autógeno, FS e laser 5J/cm2 (G5), autógeno, FS e laser 7J/cm2 (G6). Os animais foram sacrificados 6 semanas após implante. Resultados mostraram ausência de infiltrado inflamatório no defeito ósseo. Neoformação óssea ocorreu em todos os grupos, entretanto, foi mais intenso em G6. Desta maneira, o FS e laser 7J/cm2 mostraram capacidade osteocondutiva e podem ser um interessante recurso a ser aplicado nas cirurgias de reconstrução óssea.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Evaluation of reliability of FISH versus brightfield dual-probe in situ hybridization (BDISH) for frontline assessment of HER2 status in breast cancer samples in a community setting

Aims: To evaluate the reliability of novel brightfield microscopy–based dual in situ hybridization (BDISH) methods for frontline HER2 status analysis in selected suboptimally preserved breast cancer tissue samples reflecting of the worst scenario in a community. Methods and Results: A total of 320 morphologically poorly preserved breast invasive ductal carcinomas from the archives of 2 tertiary institutions in Brazil were selected for a tissue microarray–based analysis. 4B5 antibody was used for immunohistochemistry. Fluorescence in situ hybridization (FISH), DuoCISH, ZytoDot CISH, and silver in situ hybridization (SISH) were performed and compared. The highest agreement was observed between SISH and FISH. In addition, SISH was easier to assess in both amplified and nonamplified cases when compared with the other chromogenic methods, due to the sharpness of its dots. DuoCISH produced false-positive results, associated with thicker ill-defined dots, causing poor distinction between nonamplification and low amplification. ZytoDot CISH showed lower sensitivity, with increased frequency of false-positive results. Conclusions: SISH is the most reliable of the BDISH methods, with sensitivity and specificity highly comparable with FISH. It is also less deleterious than other BDISH methods, producing signals that were more distinct and therefore more readily analyzable even in poorly preserved tissue