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Dive into the research topics where Sérgio Antonio Barbosa do Nascimento is active.

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Featured researches published by Sérgio Antonio Barbosa do Nascimento.


Clinics | 2007

Classical osteoblastoma, atypical osteoblastoma, and osteosarcoma: a comparative study based on clinical, histological, and biological parameters

Cláudia Regina Gomes Cardim Mendes de Oliveira; Berenice Bilharino de Mendonça; Olavo Pires de Camargo; Emilia M. Pinto; Sérgio Antonio Barbosa do Nascimento; Maria do Rosário Dias de Oliveira Latorre; Maria Claudia Nogueira Zerbini

OBJECTIVE To investigate the biological behavior of classical and atypical osteoblastomas in comparison to osteosarcomas. METHODS Based on histological parameters, 30 osteoblastomas were subclassified as classical osteoblastomas (23/30) or atypical osteoblastoma (high cellularity, prominent blue osteoid, and epithelioid osteoblasts--7/30). Comparative immunohistochemical and clinical analysis was performed in 17 cases of patients with high-grade osteosarcoma. Formalin-fixed, paraffin-embedded archival tissue was immunostained for p53 and proliferation cell nuclear antigen. Tumors with positive p53 stain underwent molecular analyses for fragments of exon 10. RESULTS The mean proliferating cell nuclear antigen indexes for classical osteoblastoma, atypical osteoblastoma, and osteosarcoma were 33%, 61%, and 79%, respectively. The atypical subgroup showed similar results to those of the osteosarcoma group (P < 0.001). p53 protein was detected in 4 (13%) osteoblastomas (3 of these were atypical osteoblastoma), and 4 osteosarcomas (23%) also showed p53 positivity. DNA mutation performed in p53-positive cases was confirmed in exon 10 in 2 atypical osteoblastomas (2/3), 1 classical osteoblastoma (1/1), and 1 osteosarcoma (1/4). Disease recurrence was correlated with p53 expression (P = 0.009), atypical subtype (P = 0.031), spiculated blue bone on histology (P = 0.018), and proliferating-cell nuclear antigen labeling index > or =40 (P = 0.015). CONCLUSION These results validate atypical osteoblastoma as an entity, with p53 and proliferation cell nuclear antigen immuno-expression closer to that of osteosarcoma than of classical osteoblastoma. Proliferating cell nuclear antigen labeling index and p53 may be useful predictors of recurrence.


American Journal of Forensic Medicine and Pathology | 2005

A qualitative study of compact bone microstructure and nuclear short tandem repeat obtained from femur of human remains found on the ground and exhumed 3 years after death.

Edna Sadayo Miazato Iwamura; Cláudia Regina Gomes Cardim Mendes de Oliveira; José Arnaldo Soares-Vieira; Sérgio Antonio Barbosa do Nascimento; Daniel Romero Muñoz

Forensic identification of human remains is composed of anthropological study of race, sex, age, etc. By using these traditional methods, inconclusive or nonidentified cases could be subjected to DNA analysis. However, in spite of advances in human identification techniques, especially by PCR-amplified DNA, some limitations that affect the ability of obtaining DNA from human remains still persist. Light microscope sections of postmortem compact bones from human remains are presented here for the purpose of increasing a forensic examiners prediction of successful nuclear DNA typing. Femoral compact bones were obtained from 7 human remains found on the ground, in different degrees of decomposition, and were cleaned by boiling to remove soft tissues, 8 collections of bones having undergone natural decomposition, not boiled (as no soft tissue was adhered), and 5 cadavers 12 to 16 hours postmortem. The histologic sections were stained by hematoxylin and eosin, the loci CSF1PO, TPOX, TH01, F13A01, FESFPS, vWA, D16S539, D7S820, D13S317, and amelogenin were amplified by PCR, and the polyacrylamide gel was stained with silver. The results presented here clarify questions concerning the viability of DNA for identification analysis, and they also may help to establish better strategies for optimization of DNA extraction and analysis in compact bones of human remains.


Revista Do Instituto De Medicina Tropical De Sao Paulo | 1996

Parinaud syndrome caused by Bartonella henselae: case report

Carlos Alberto Yamashita; Adriana Mielle; Natasha Slhessarenko; Sérgio Antonio Barbosa do Nascimento; Alfredo Elias Gilio; Marcia Melo Campos Pahl; Bernardo Ejzenberg; Evandro Roberto Baldacci; Yassuhiko Okay

The authors report a case of Parinaud syndrome (conjunctivitis with pre-auricular satellite adenitis) caused by Bartonella henselae, the etiologic agent of Cat Scratch Disease. The etiologic assessment of this case was performed by serum indirect immunofluorescence reaction and allowed for a better therapeutics and follow up, avoiding ineffective antibiotics and surgical interventions.


Acta Ortopedica Brasileira | 2009

Estudo histopatológico do trajeto de biópsia de tumores musculoesqueléticos malignos

Marcelo Barbosa Ribeiro; Claudia Regina G. C. Mendes de Oliveira; Renée Zon Filippi; André Mathias Baptista; Marcelo Tadeu Caiero; Carlos Fernando Saito; Sérgio Antonio Barbosa do Nascimento; Olavo Pires de Camargo

OBJECTIVE: To investigate whether there is any risk of seeding by neoplasic cells along biopsy tracks and to study local histological abnormalities. METHODS: This was a prospective study on biopsy tracks in patients who underwent operations due to malignant musculoskeletal tumors between April 2006 and April 2007. RESULTS: Neoplasic cell implantation occurred in 32% of the tracks. The most common histological abnormalities in positive cases were classified as severe fibrosis, mild inflammatory component and severe neovascularization. CONCLUSION: We suggest that traditional oncological resection of the track should be carried out together with excision of the specimen.


Brazilian Journal of Cardiovascular Surgery | 2004

In vivo endothelialization of cardiac bioprostheses: conventional versus non-aldehyde preservation

Vinicius José da Silva Nina; Pablo Maria Alberto Pomerantzeff; Ivan Sergio Joviano Casagrande; David Chung; Carlos Manuel de Almeida Brandão; Sérgio Antonio Barbosa do Nascimento; Luiz Alberto Benvenuti; Sérgio Almeida de Oliveira

Objective: A protective layer of endothelial cells (EC) of host origin on the entire surface of bioprosthetic heart valves has never been reported. Current commercial bioprosthetic heart valves are commonly preserved in glutaraldehyde (GA) and are cytotoxic to host cells preventing spontaneous endothelialization. The aim of this study is to demonstrate the potential for in vivo endothelialization of heart valves treated by the L.-Hydro™ preservation process. Method: L-Hydro™ preservation process consists of mild extraction of antigenic substances by the action of polyethyleneglycol and incorporation of an antiinflammatory and a anti-thrombotic agent. Seven stented porcine valves treated by the L-Hydro™ process and three GA-fixed porcine valves were implanted in the mitral position of juvenile sheep. The valves were evaluated by echocardiography and angiography prior to sacrifice at five months. Recovered valves were also histologically and histochemically evaluated. Results: There were no hemodynamic differences between the groups. However, scanning and transmission electron microscopy showed a nearly complete coverage of EC on the surfaces of all leaflets in the L-Hydro™ treated valves. The EC were in direct contact with the underlying collagen layer and expressed von Willebrand-related antigens (vW). The surfaces of the GA-treated valves were covered by fibrin deposition, macrophages, calcium and thrombotic material. Only sparse EC were observed and contact of the EC where the underlying tissue was incomplete. Conclusion: These data indicate that L-Hydro™ treated porcine valve tissues are capable of inducing spontaneous endothelialization with evidence of strong cell attachment of the new endothelium to the collagen matrix.


Revista Da Sociedade Brasileira De Medicina Tropical | 1992

Emprego da azida sódica, como conservador de fezes, para a pesquisa de ovos de Schistosoma mansoni e de outros helmintos, pelo método de Kato-Katz: estudo em área endêmica

Vicente Amato Neto; Pedro Luiz Silva Pinto; Ogvalda Dawey de Souza Torres; Luís Matsubara; Lúcia Maria Almeida Braz; Sérgio Antonio Barbosa do Nascimento

In two aliquots of 208 samples of stool, tests have been made by the Kato-Katz method, one being made after the use of 0.2mg of sodic azide for 200mg, and the other without the aforesaid conservant. The resulted percentages with or without the conservant were, respectively, for Ancylostomideos: 12.5 and 25.9; for Ascaris lumbrieoides; 71.6 and 72.5; for Schistosoma mansoni: 7.6 and 17.7, and for Trichuris trichiura: 86 and 85. The count of the eggs with and without the conservant was, respectively, 264 and 539 for Ancylostomideos, 13186 and 33751 for A. lumbricoides, 55.5 and 63.5 for S. mansoni, and 1345 and 2068 for T. trichiura. The authors did not confirm the advantage of using sodic azide for study in endemic areas. They suggest that the exsiccation of the stool and the low intensity of infections can explain the unfavourable results of the present clinical trial.


Revista Do Instituto De Medicina Tropical De Sao Paulo | 1990

Observaçöes sobre a viabilidade do Trypanosoma cruzi no caldo da cana

Pedro Luiz Silva Pinto; Vicente Amato Neto; Sérgio Antonio Barbosa do Nascimento; Hertha Barbara Wüllert Telles de Souza; Akimi Miyamoto; Antonio Augusto Baillot Moreira; Lúcia Maria Almeida Braz


Revista do hospital das clinicas. Faculdade de medicina da Universidade de Sao Paulo | 1989

Avaliaçäo da utilidade do Coprotest para exame parasitológico das fezes

Vicente Amato Neto; Rubens Campos; Pedro Luiz Silva Pinto; Luís Matsubara; Lúcia Maria Almeida Braz; Akimi Miyamoto; Roberto Foster; Sérgio Antonio Barbosa do Nascimento; Hertha Barbara Wüllert Telles de Souza; Antonio Augusto Baillot Moreira


Rev. Hosp. Clin. Fac. Med. Univ. Säo Paulo | 1990

Estudo sobre a possível atividade terapêutica da deferoxamina na infecçäo experimental de camundongos pelo Plasmodium berghei

Lúcia Maria Almeida Braz; Vicente Amato Neto; Rubens Campos; Antonio Augusto Baillot Moreira; Roberta Foster; Sérgio Antonio Barbosa do Nascimento; Akimi Miyamoto


Acta Ortopedica Brasileira | 2009

Estudo histopatolgico do trajeto de bipsia de tumores musculoesquelticos malignos

Marcelo Barbosa Ribeiro; Claudia Regina G. C. Mendes de Oliveira; Renée Zon Filippi; André Mathias Baptista; Marcelo Tadeu Caiero; Carlos Fernando Saito; Sérgio Antonio Barbosa do Nascimento; Olavo Pires de Camargo

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Ivan Sergio Joviano Casagrande

Universidade Federal de Minas Gerais

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