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Dive into the research topics where Bernardo Silveira Volkweis is active.

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Featured researches published by Bernardo Silveira Volkweis.


Revista do Colégio Brasileiro de Cirurgiões | 2016

Reliability of nutritional assessment in patients with gastrointestinal tumors

Aline Kirjner Poziomyck; Ana Valeria Goncalves Fruchtenicht; Geórgia Brum Kabke; Bernardo Silveira Volkweis; Jorge Luiz Antoniazzi; Luis Fernando Moreira

Patients with gastrointestinal cancer and malnutrition are less likely to tolerate major surgical procedures, radiotherapy or chemotherapy. In general, they display a higher incidence of complications such as infection, dehiscence and sepsis, which increases the length of stay and risk of death, and reduces quality of life. The aim of this review is to discuss the pros and cons of different points of view to assess nutritional risk in patients with gastrointestinal tract (GIT) tumors and their viability, considering the current understanding and screening approaches in the field. A better combination of anthropometric, laboratory and subjective evaluations is needed in patients with GIT cancer, since malnutrition in these patients is usually much more severe than in those patients with tumors at sites other than the GIT. RESUMO Pacientes com neoplasia gastrointestinal e desnutridos são menos propensos a tolerar procedimentos cirúrgicos de grande porte, radioterapia ou quimioterapia. Em geral, apresentam maior incidência de complicações, como infecção, deiscência e sepse, o que aumenta o tempo de internação e o risco de morte, e reduz a qualidade de vida. O objetivo desta revisão é abordar os prós e contras de diferentes pontos de vista que avaliam risco nutricional em pacientes com tumores do Trato Gastrointestinal (TGI) e sua viabilidade, considerando o atual entendimento e abordagens de triagem neste campo. Melhor combinação de avaliações antropométricas, laboratoriais e subjetivas se faz necessária em pacientes com câncer do TGI, uma vez que a desnutrição nestes pacientes costuma ser muito mais grave do que naqueles indivíduos com tumores em outros sítios que não o TGI.


Gastroenterology Research and Practice | 2012

Ki-67 Antigen Overexpression Is Associated with the Metaplasia-Adenocarcinoma Sequence in Barrett's Esophagus

Bernardo Silveira Volkweis; Richard Ricachenevsky Gurski; Luíse Meurer; Guilherme Gonçalves Pretto; Guilherme da Silva Mazzini; Maria Isabel Albano Edelweiss

Introduction. The objective of this study was to evaluate Ki-67 antigen expression in patients with Barretts esophagus and esophageal adenocarcinoma and to assess its correlation with the metaplasia-esophageal adenocarcinoma progression. Methods. Using immunohistochemistry we evaluated the Ki-67 index in patients with Barretts esophagus, esophageal adenocarcinoma, and controls. We included patients with endoscopically visible columnar mucosa of the distal esophagus (whose biopsies revealed specialized intestinal-type metaplasia), patients with esophageal and esophagogastric tumors types I and II, and patients with histologically normal gastric mucosa (control). Results. In the 57 patients studied there were no statistically significant differences between the groups with respect to age or race. Patients with cancer were predominantly men. The Ki-67 index averaged 10 ± 4 % in patients with normal gastric mucosa (n = 17), 21 ± 15 % in patients with Barretts esophagus (n = 21), and 38 ± 16 % in patients with cancer (n = 19). Ki-67 expression was significantly different between all groups (P < 0.05). There was a strong linear correlation between Ki-67 expression and the metaplasia-adenocarcinoma sequence (P < 0.01). In patients with cancer, Ki-67 was not associated with clinical or surgical staging. Conclusions. Ki-67 antigen has increased expression along the metaplasia-adenocarcinoma sequence. There is a strong linear correlation between Ki-67 proliferative activity and Barretts carcinogenesis.


ABCD. Arquivos Brasileiros de Cirurgia Digestiva (São Paulo) | 2008

Tratamento cirúrgico do divertículo de Zenker

Guilherme Behrend Silva Ribeiro; Fernando Rossi Mielke; Bernardo Silveira Volkweis; Carlos Cauduro Schirmer; Cleber Dario Pinto Kruel; Gustavo Morellato; Marcelo Binato; Richard Ricachenevsky Gurski

RACIONAL: O tratamento cirurgico do diverticulo de Zenker inclui na maioria dos casos a cricomiotomia do musculo cricofaringeo, a qual pode ser associada a diverticulopexia ou diverticulectomia. A escolha destas opcoes cirurgicas ainda e controversa. OBJETIVO: Avaliar os resultados de dois tratamentos cirurgicos (diverticulopexia ou diverticulectomia, ambos associados a cricomiotomia) em uma serie de casos. METODOS: Estudo retrospectivo em periodo de 10 anos de 26 pacientes submetidos ao tratamento cirurgico do diverticulo de Zenker. Para analise estatistica, os pacientes foram divididos em dois grupos: Grupo 1 - diverticulectomia (n=17) e Grupo 2 - diverticulopexia (n=9). Em todos realizou-se miotomia. Foram avaliadas as variaveis: tempo cirurgico, de internacao e de inicio da alimentacao via oral, complicacoes gerais, ocorrencia de fistulas, recidiva dos sintomas e mortalidade. Consideraram-se diferencas significativas quando P<0.05. RESULTADOS: A idade media dos pacientes foi de 64 anos. Sintomas pre-operatorios principais: disfagia (91%) e regurgitacao (46%). Todos foram investigados com estudo radiografico contrastado de faringe-esofago-estomago e 58% dos casos com endoscopia digestiva alta. Nao houve diferenca significativa entre os Grupos 1 e 2 em relacao ao tempo operatorio (96 x 99 min), tempo de internacao (5,5 x 5 dias), inicio da alimentacao via oral (7,5 x 4 dias), ocorrencia de fistulas esofago-cutâneas (35 x 22%), recidiva da disfagia (6 x 11%), complicacoes pos-operatorias em geral (41 x 33%) e tempo de seguimento (7,5 x 9 meses). A mortalidade foi nula. CONCLUSAO: O tratamento cirurgico do diverticulo de Zenker e metodo terapeutico relativamente seguro, com morbidade aceitavel e seus resultados independem da opcao por resseccao ou pexia do diverticulo.


Anticancer Research | 2018

CD117 Expression in Squamous Cell Carcinoma of the Oesophagus

Luis Fernando Moreira; Marcelo Marafon Maino; Henrique Iahnke Garbin; Gabriella Richter Da Natividade; Bernardo Silveira Volkweis; Jane Ulbricht Kulczynski

Background/Aim: Identification of changes in specific genes may help new attempts in finding targeted therapy for oesophageal cancer which still has a very poor prognosis. The aim of this study was to investigate CD117 expression in squamous cell carcinoma of the oesophagus (SCCO). Materials and Methods: A preliminary study was performed for CD177 immunoreactivity using a monoclonal antibody against CD117 on 27 SCCO specimens from patients who underwent surgical resection. Specimens of oesophageal mucosa obtained from 10 healthy individuals were studied as a control group. Results: Most patients had TNM American Joint Committee on Cancer stage IIb or III SCCO and mean overall survival was 21 (range=2-72) months. Cytoplasmic membrane CD117 immunoreactivity was demonstrated in only four (15%) out of 27 tumours and in none of the controls. Conclusion: Although immunohistochemical expression of CD117 was higher than previously demonstrated, the lack of expression does not warranty further use in targeted therapy of SCCO.


Revista do Colégio Brasileiro de Cirurgiões | 2016

Cultural adaptation and the Clavien-Dindo surgical complications classification translated to Brazilian Portuguese.

Luis Fernando Moreira; Marcelo Castro Marçal Pessôa; Diego Sachet Mattana; Fernando Fernandes Schmitz; Bernardo Silveira Volkweis; Jorge Luiz Antoniazzi; Liacyr Ribeiro

OBJECTIVE to generate a translated and validated version of the Clavien-Dindo Classification of Surgical Complications (CDC) to Brazilian Portuguese (CDC-BR). METHODS the process of translation and adaptation followed the guideline of Beaton et al., 2000. We divided 76 participating surgeons, in different levels of experience, from the Department Surgery of the Hospital de Clínicas de Porto Alegre, into two groups: Group I applied the original version (CDC, n=36);r Group II used the modified version (CDC-BR, n=40). Each group classified 15 clinical cases of surgical complications. We compared performance between the groups (Mann-Whitney test) relating to the level of experience of the surgeon (Kruskal-Wallis test), considering p value <0.05 as significant. RESULTS the performance of the Group II (CDC-BR) was higher, with 85% accuracy, compared with 79% of Group I (CDC), p-value =0.012. The performance of the groups as for surgeons experience displayed p=0.171 for Group I, p=0.528 for Group II, and p=0.135 for overall performance. CONCLUSION we produced a translated and validated version of the CDC for Brazilian Portuguese. The instrument will be a useful tool in the production of evidence on surgical outcomes. OBJETIVO gerar uma versão traduzida e validada da Classificação de Complicações Cirúrgicas de Clavien-Dindo (CCD) para o Português-Brasileiro (CCD-BR). MÉTODOS o processo de tradução e adaptação seguiu a diretriz de Beaton et al., de 2000. Formaram-se dois grupos, Grupo I, que utilizou a versão original (CCD, n=36) testado em relação ao Grupo II, com a versão modificada (CCD-BR, n=40), com um total de 76 cirurgiões participantes em níveis de experiência distintos do Departamento de Cirurgia do Hospital de Clínicas de Porto Alegre. Quinze casos clínicos de complicações cirúrgicas foram classificados em cada grupo. Comparou-se o desempenho entre grupos (teste de Mann-Whitney) relacionando ao nível de experiência dos cirurgiões (teste de Kruskal-Wallis). Valor de p<0,05 como significativo. RESULTADOS o desempenho do Grupo II (CCD-BR) foi superior, com 85% de acertos, contra 79% do Grupo I (CCD), p-valor=0,012 do teste de Mann-Whitney. O desempenho dos grupos em relação à experiência dos cirurgiões foi p-valor=0,171 para o Grupo I, p-valor=0,528 para o Grupo II, e p-valor=0,135 para o desempenho geral, teste de Kruskal-Wallis. CONCLUSÃO foi produzida uma versão traduzida e validada da CCD para o Português-Brasileiro. O instrumento produzido será ferramenta útil na produção de evidências sobre os resultados cirúrgicos.


Revista do Colégio Brasileiro de Cirurgiões | 2008

Esôfago de Barrett: aspectos fisiopatológicos e moleculares da seqüência metaplasia-displasia-adenocarcinoma - artigo de revisão

Bernardo Silveira Volkweis; Richard Ricachenevsky Gurski

The Barretts esophagus (BE) is defined as endoscopically visible columnar mucosa at the distal esophagus, of any extension, proved to harbor intestinal metaplasia on biopsy, highlighted by the presence of goblet cells. BE denotes long-standing gastroesophageal reflux disease (GERD) and is an important risk factor for the development of esophageal adenocarcinoma (EAC). Therefore, these patients must be on follow-up, in order to diagnose cancer early. BE patients have frequent alterations in esophageal physiologyc studies. Alkaline duodenogastroesophageal reflux seems to have important role. The development BE occurs in steps, initially with formation of cardiac type mucosa subsequent intestinalization. Futher progression can follow a sequence, from low grade dysplasia, to high grade dysplasia and esophageal adenocarcinoma. Current follow-up is based on the presence of dysplasia. It has limitations, grouping patients heterogeneously. Different steps of carcinogenesis have been studied looking for an ideal prognostic marker. Uncontrolled proliferative activity, apoptosis inhibition, angiogenesis, tissue invasion and metastases formation are all implicated in cancer origin. Some cycle cell molecules have been studied in BE, such as retinoblastoma protein, ciclins, kinase dependent ciclins and cell cycle inhibitors. The P53 protein is one of the most investigated in the metaplasia-adenocarcinoma progression. Growth Factors, apoptotic proteins, telomers and DNA ploidy have also been searched. Increased proliferative activity has been implicated in Barretts carcinogenesis and the Ki-67 antigen, through imunohistochemical analysis, has become the the method of choice. Present in the nucleus, it is found in proliferative cells only. Some studies suport association between Ki-67 activity and the metaplasia-dysplasia-adenocarcinoma sequence.The results, however, are inconclusive and research should follow this way.


Journal of Surgical Research | 2008

Mouse Model of Diethylnitrosamine-Induced Gastric Cancer

Marcelo Binato; Marcelo Kruel Schmidt; Bernardo Silveira Volkweis; Guilherme Behrend Silva Ribeiro; Maria Isabel Albano Edelweiss; Richard Ricachenevsky Gurski


Archive | 2008

TRATAMENTO CIRÚRGICO DO DIVERTÍCULO DE ZENKER Surgical treatment of Zenker's diverticulum

Guilherme Behrend; Silva Ribeiro; Fernando Rossi Mielke; Bernardo Silveira Volkweis; Carlos Cauduro Schirmer; Cleber Dario; Pinto Kruel; Gustavo Morellato; Marcelo Binato


Archive | 2008

Mous eMode lo fDiethylnitrosamine-Induce dGastri cCancer

Marcelo Binato; Marcelo Kruel Schmidt; Bernardo Silveira Volkweis; Guilherme Behrend Silva Ribeiro; Maria Isabel Albano Edelweiss; Richard Ricachenevsky Gurski


Gastroenterology | 2008

W1833 KI-67 Antigen Is Overexpressed in Barrett's Carcinogenesis

Bernardo Silveira Volkweis; Richard Ricachenevsky Gurski; Luíse Meurer; Maria Isabel Albano Edelweiss; Gustavo Morellato; Marcelo Kruel Schmidt

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Richard Ricachenevsky Gurski

Universidade Federal do Rio Grande do Sul

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Maria Isabel Albano Edelweiss

Universidade Federal do Rio Grande do Sul

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Guilherme Behrend Silva Ribeiro

Universidade Federal do Rio Grande do Sul

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Marcelo Binato

Universidade Federal do Rio Grande do Sul

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Marcelo Kruel Schmidt

Universidade Federal do Rio Grande do Sul

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Carlos Cauduro Schirmer

Universidade Federal do Rio Grande do Sul

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Luis Fernando Moreira

Universidade Federal do Rio Grande do Sul

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Luíse Meurer

Universidade Federal do Rio Grande do Sul

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Jorge Luiz Antoniazzi

Universidade Federal do Rio Grande do Sul

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Aline Kirjner Poziomyck

Universidade Federal do Rio Grande do Sul

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