Biomedical subjects

Alberto Goldenberg

Publications and source records attributed to Alberto Goldenberg.

8 recordsLinked to original sources

PubMed2006

Liver retransplantation: a model for determining long-term survival.

BACKGROUND: Because of the worse results from retransplantation in relation to the initial liver transplantation, there is a need to refine the indication for retransplantation, such that fair distribution of this benefit is obtained. METHODS: This was a study of 139 patients who underwent liver retransplantation. Thirty variables were studied: 18 relating to the recipient and 12 to the donor. All the independent variables were initially compared with the length of survival using univariate analyses. Variables presenting significance were compared with the dependent variable of length of survival, to determine which factors were related to longer survival among patients, when evaluated together. RESULTS: A multivariate model for determining long-term survival among patients with retransplants was built up using the following variables: recipient's age, creatinine, urgency of retransplantation and early failure of the first graft. Through this multivariate model it was possible to determine a score that was categorized according to tertile distributions (below the 33rd percentile, score <24; 33rd to 66th percentile, 24 < or = score < or = 32; above the 66th percentile, score > 32). One-year, 3-year, and 5-year patient survival rates following retransplantation were respectively 85%, 82%, and 77% for scores <24; 69%, 66%, and 61% for scores between 24 and 32; and 21%, 19%, and 16% for scores >32 (P < 0.0001). CONCLUSION: The variables of recipient's age, creatinine, urgency of retransplantation, and early failure of the initial transplantation were factors that were independently related to the long-term survival of patients with liver retransplants.

Adolescent↗

PubMed2006

[Pancreatic insulinomas].

Insulinoma is the most frequent neuroendocrine pancreatic tumor. In the present study, the clinical and immunohistochemical results of 20 patients who underwent surgery between January 1986 and December 2004 were evaluated. Clinical presentation, laboratory data, imaging studies, aspects of the surgical technique, complication rates and medium- and long-term follow-up were analyzed. Surgical treatment was recommended in all patients based on presenting symptoms and laboratory signs of hypoglycemia and hyperinsulinemia. In 15 patients, the lesion was identified preoperatively. In the 5 remaining patients, intraoperative palpation and ultrasonography were used to locate the lesion. The most frequently performed surgical procedures were pancreatic resection in 10 patients and laparotomic enucleation in the remaining 10. Laparoscopy was used in two patients. Two patients developed diabetes mellitus. The most frequent surgical complication was pancreatic fistula. No mortality was observed in the present series. Symptom reversion, characterized by disappearance of Whipple's triad and normal or increased glycemia values compared with preoperative values, was observed in all patients.

Adolescent↗

PubMed2005

Assessment of staging, prognosis and mortality of colorectal cancer by tumor markers: receptor erbB-2 and cadherins.

PURPOSE: To evaluate the prognostic significance and correlation with staging and degree of cell differentiation of the tumoral expression of the proteins c-erbB-2 and E-cadherin, in patients with colorectal adenocarcinoma. METHODS: The study included 117 patients with an average age of 63.1 years and an average follow-up duration of 28.1 months. The disease-free interval, survival, incidence of recurrence and specific mortality were evaluated. c-erbB-2 anti-oncoprotein antibodies (Dako) were utilized via the streptavidin-biotin technique. Samples were considered to be positive for c-erbB-2 if 10% or more of the tumor cell membranes were stained. The anti-E-cadherin antibodies (Dako), evaluated this protein and is considered positive, if 50% or more of the cell membranes were stained. Statistical analysis was performed using Pearson's chi-squared test, Fisher's exact test, Kaplan-Meier's estimator, the log-rank test and Wilcoxon's test (Breslow version), setting the level of statistical significance at 5% (p<0.05). RESULTS: 52 of 108 patients studied for c-erbB-2 were positive (48.1%), 47 of 93 patients studied for E-cadherin were negative (50.5%). These data do not express any correlation with TNM (tumor, node and metastasis) staging and the degree of cell differentiation or with the tumor recurrence rate. The disease-free interval among patients who were positive for c-erbB-2 and negative for E-cadherin was 68.0 months and did not differ from those with c-erbB-2 negative and E-cadherin positive (55.0 months--p = 0.5510). The average survival among patients positive for c-erbB-2 and negative for E-cadherin was 75 months without statistical significance difference with the other group (61 months--p = 0.5256). Specific mortality occurred in 20.0% of the cases and did not correlate with the expression of c-erbB-2 (p=0.446), E-cadherin (p=0.883). CONCLUSION: The tumoral expression of c-erbB-2 and E-cadherin did not demonstrate a correlation with the staging and degree of cell differentiation, and it did not present prognostic value regarding disease recurrence, disease-free interval, survival and specific mortality among patients with colorectal adenocarcinoma.

Adenocarcinoma↗

PubMed2005

Experimental model of gastroesophageal reflux in rats.

PURPOSE: To develop an experimental model of gastroesophageal reflux in rats. METHODS: Sixty Wistar rats underwent surgery and were assigned to one of the three groups of twenty animals each. The animals in group A underwent total esophageal myectomy and, in group (B), underwent partial myectomy. The third group was the control group (C). A contrast radiographic study of the esophagus was performed to evaluate gastroesophageal reflux. The anatomopathological study of the esophagus was used to evaluate esophagitis. RESULTS: During the 30-day postoperative follow-up, 14 animals in group A presented with reflux of barium in the esophagus. The presence of barium in the esophagus was observed in 7 animals in group B and in 2 animals in the control group. The result of the histopathology examination was controversial. A marked weight loss in the rats undergoing total myectomy was observed, however there was no significant statistical difference. CONCLUSION: Total myectomy in the lower third of the esophagus caused gastroesophageal reflux in the majority of the animals.

Animals↗

PubMed2005

Effects of the polypropylene mesh implanted through inguinotomy in the spermatic funiculus, epididium and testis of dogs.

PURPOSE: To investigate the effects of polypropylene mesh, implanted by inguinotomy, in the spermatic funiculus, epididium and testis of dogs. METHODS: Eighteen dogs were considered (12-23 Kg), separated in three groups. Group A (n=7): left side (with mesh) versus right side (without mesh); Group B (n=7): left side (without mesh) versus right side (with mesh) and Group C (n=4): without any surgical manipulation (control group). After being observed for 60 days, the animals were subjected to bilateral removal of the spermatic funiculus, epididium and testis that were submitted to histological analysis. During the re-operation, a macroscopic evaluation was performed. RESULTS: On the mesh side, we noted 100% of mesh adherence to the posterior wall of the inguinal canal, as well as the adherence of the spermatic funiculus to the mesh. A congestion of the pampiniform plexus was noted in three animals. Chronic inflammation reaction and foreign body reaction in the spermatic funiculus was observed in 100% of the animals. On the side that did not carry a mesh, chronic inflammatory reaction was observed in 71% of the animals. All the animals presented chronic inflammatory reaction in the deferent duct in the mesh side and in eleven animals in the side without the mesh. These alterations were not found in Group C. There was a considerable statistical reduction in the average difference of the diameter of the lumen of the deferent duct in the mesh side. In the epididium and testis, macro and microscopic alterations were not significant, although one animal presented a marked reduction of spermatogenesis on the mesh side. CONCLUSION: The polypropylene mesh, when in contact with the spermatic funiculus of dogs, causes a more intense chronic inflammatory reaction and a significant reduction in the diameter of the lumen of the deferent duct.

Animals↗

PubMed2005

Comparative study of inflammatory response and adhesions formation after fixation of different meshes for inguinal hernia repair in rabbits.

PURPOSE: Compare, in a rabbit model, the inflammatory response and adhesions formation following surgical fixation of polypropilene and Vypro mesh in the inguinal preperitoneal space. METHODS: Fourteen male New Zealand rabbits, weighing between 2.000 to 2.500 g were used. A midline incision was made and the peritoneal cavity was exposed. The 2.0 x 1.0 cm polypropylene mesh was fixed in the left flank and secured to the margins with 3-0 prolene in a separate pattern. In the right flank, a 2.0 x 1.0 cm Vypro II mesh was sewn in the same way. After the post surgical period, the animals were again anesthetized and underwent laparoscopic approach, in order to identify and evaluate adhesions degree. Both fixed prosthesis were excised bilaterally with the abdominal wall segment, including peritoneum, aponeurosis and muscle and sent to a pathologist. RESULTS: Operative time ranged from 15 to 25 minutes and no difficulties in applying the mesh were found. From the 14 polypropylene meshes fixed to the intact peritoneum, 11 had adhesions to the abdominal cavity (78.6%). Concerning Vypro mesh, 12 animals developed adhesions from the 14 with mesh fixation (85.7%). Histological examination of tissues harvested revealed fibroblasts, collagen, macrophages and lymphocytes between the threads of the mesh. CONCLUSION: Polypropylene and Vypro mesh, when implanted in the peritoneal cavity of rabbits provoke similar amount of adhesions. Vypro mesh tissues had higher fibrosis resulting in better mesh incorporation to the abdominal wall.

Animals↗

PubMed2005

Analysis of the correlation between p53 and bcl-2 expression with staging and prognosis of the colorectal adenocarcinoma.

PURPOSE: To analyze the correlation between p53 and bcl-2 expression and colorectal adenocarcinoma staging and prognosis. METHODS: This was a retrospective series of 125 colorectal adenocarcinoma patients (67 women and 58 men; ages 30-87 years) who underwent surgery with curative intent. The mean follow-up was 28.5 months (range: 2-96 months). TNM staging, tumor recurrence, survival and cancer-related mortality were analyzed. Immunoreactivity was evaluated using DO7 (Dako) for p53 and K492 (Dako) for bcl-2. Tumors with accumulation of staining for cytoplasmic bcl-2 or nuclear p53 in more than 10% of cells were considered positive. Statistical analysis utilized Pearson chi-squared, log-rank and Wilcoxon tests, and Kaplan-Meier survival estimation (significance level: p<0.05). RESULTS: p53+ was found in 11.8% (14/118), bcl-2+ in 50% (58/116) and associated p53+/bcl-2+ in 6.4% (7/109) of the tumors. There was no significant correlation between expression of these biomarkers and TNM I, II, III and IV staging (p=0.385 for p53; p=0.461 for bcl-2). For tumor recurrence, p53+ was found in 9.5% (2/21), bcl-2+ in 50% (11/22), and associated p53+/bcl-2+ in 5.2% (1/19) of the tumors (p=0.714, p=1.000 and p=0.960, respectively). For survival analysis, p53+: 57 months (45.0-68.0), bcl-2+: 78 (37.0-89.0), and p53+/bcl-2+: 62 (56.0-68.0) (p=0.319). For cancer-related mortality, p53+: 8.3% (3/36), bcl-2+: 47.2% (17/36), and p53+/bcl-2+: 5.9% (2/36) of the patients (p=0.432, p=0.688 and p=0.907, respectively). CONCLUSION: No correlation was found between tumor expression of p53 and bcl-2 and the TNM staging, recurrence, survival and cancer-related mortality in colorectal adenocarcinoma.

Adenocarcinoma↗

PubMed2004

[Pancreatic insulinomas: diagnosis and treatment].

BACKGROUND: Despite its rarity, the insulinoma is the most common pancreatic neuroendocrine tumor. OBJECTIVE: Analyze clinical and immunohistochemical data from surgical resection of the pancreas insulinoma. METHOD: Twelve cases are described, concerning surgical aspects, complications and medium-long term outcome of patients. They underwent surgical treatment due to clinical suspicion and biochemical diagnosis of hypoglycemia and hyperinsulinism. RESULTS: The insulinoma was identified preoperatively in seven patients, while intraoperative ultrasonography and palpation were necessary for diagnosis in the other cases. Eight patients underwent pancreatic resection and pancreatic leak was observed in seven cases. Two patients developed diabetes mellitus and no mortality occurred in the current series. CONCLUSION: All patients presented satisfactory outcome and remained asymptomatic with normal glicemia levels.

Adolescent↗