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Biomedical subjects

V A Alves

Publications and source records attributed to V A Alves.

At least 55 records · Page 3Linked to original sources
PubMed1986

Nesidioblastosis associated with congenital malformations of the heart. Morphological and immunohistochemical study of 5 necropsy cases.

Pancreatic tissue from 5 children with congenital heart disease (CHD) with morphological alterations of the endocrine components at autopsy were compared in a double-blind semiquantitative study, which included light microscopy and immunocytochemistry, to pancreatic tissue of 5 children of similar age but without CHD. Hyperplasia and hypertrophy of islets of Langerhans, scattered endocrine cells within the exocrinic acini, cluster of endocrine cells budding from ductular epithelium or within interlobular connective tissue, and hyperplasia of ductular epithelium were found to be present in the patients with congenital cardiac defects. The observed findings resembled those present in a surgically resected pancreas from a child with clinically overt nesidioblastosis. Although this study suggests a higher incidence of endocrine pancreas disturbances in certain types of CHD, the clinical significance of these morphological alterations will require further studies.

Autopsy↗
PubMed1985

Effects of chemotherapy on mice submitted to multiple Schistosoma mansoni infections. A controlled randomized prospective study.

In an attempt to reproduce experimentally as close a possible the conditions found in endemic areas of mansonian schistosomiasis, a controlled trial in mice submitted to weakly infections with cercariae of S. mansoni was performed. One group (I) was not treated, the other (II) was treated with a single oral doses (100 mg/kg) of oxamniquine at the 13th week. After treatment infections were maintained bi-weekly. Mortality was significantly higher in group I (p less than 0.0001). A comparative morphological and immunoenzymatic study of the liver in the two groups was also carried out, showing a tendency to smaller granulomas and to more efficient antigen restriction in the treated group.

Administration, Oral↗
PubMed1984

Hepatosplenic schistosomiasis mansoni: ultrasound manifestations.

Ultrasound (US) was performed in 103 patients with hepatosplenic schistosomiasis mansoni. The abnormal US findings are reported and correlated with the pathologic and anatomic characteristics. The main US findings are periportal fibrosis, left lobe hypertrophy, thickening of the wall of the gallbladder, granulomas, splenic nodules, and widening of the portal vessel system. Frequent but nonspecific findings include splenomegaly and the presence of collateral vessels. Portal vein thrombosis was present in a few cases. It is concluded that US is a major tool in the diagnosis of this disease.

Humans↗
PubMedDate not supplied

Primary malignant epithelial tumors of the liver in children: a study of DNA content and oncogene expression.

Primary malignant epithelial tumors of the liver (PMETL) are rare in the pediatric age group, and very little is known about their biology as compared with adult tumors. The prognostic value of the DNA contents measured by image analysis and expression of oncogene c-erb2 and tumor suppressor gene p53 were studied in 30 cases of PMETL in children, including 24 with hepatoblastomas (HB) and 6 with hepatocellular carcinomas (HCC). p53 overexpression was detected in 12 out of 26 cases (46.0%), or in 3 of 5 HCC and 9 of 21 HB cases. A relatively high concordance of staining was observed with the two antibodies used (clone DO7, Dako and clone DO1, Santa Cruz Biotechnology). c-erb-B2 did not yield the characteristic membrane staining in any of the 27 cases in which reliable staining was obtained. However, 1 out of 4 patients with HCC and 1 of 23 with HB revealed strong granular cytoplasmic staining in several neoplastic cells. Interestingly, these were two of the three aneuploid multiploid cases. DNA histograms of 13 out of 29 cases (54.8%) were classified as DNA aneuploid (5/6 HCC and 8/23 HB): nine were hyperdiploid, one was hypodiploid (1HB), and three were multiploid (2HB and 1HCC). In the HB group, DNA aneuploidy was strongly associated with embryonal histological areas, suggesting that a disturbance in the process of cell differentiation is associated with marked genetic aberrations. Only the group of HB was submitted to univariate analysis of survival by the Kaplan-Meier method for age (< 24 months vs. > or = 24 months), sex, preoperative chemotherapy (yes vs. no), residual disease (metastasis, and/or unresectable tumor), p53 expression by immunohistochemistry (positive vs. negative), and DNA ploidy (diploid vs. aneuploid). Only residual disease at the time of diagnosis (P < 0.017) and preoperative chemotherapy (0.030) were found to be negatively correlated with biological behavior, estimated as overall survival. DNA aneuploidy tumors (P < 0.125) and male patients (P = 0.123) showed a trend toward a more aggressive clinical behavior, although the difference was not statistically significant. Combining DNA ploidy and residual disease, patients were categorized into three groups: group I, patients with no adverse prognostic factors, i.e., diploid tumors without residual disease; group II, patients with only one adverse prognostic factor, i.e., aneuploid tumor or residual disease; and group III, patients with both adverse factors, aneuploid tumors and residual disease at time of diagnosis. A log-rank test comparing the three survival curves showed a statistically significant difference between them (P < 0.003). Although the series of cases is small, the results of this study highlight the importance of including DNA ploidy in the protocols designed for HB in children by international cooperative groups.

Adolescent↗
PubMedDate not supplied

Immunocytochemistry applied to aspiration biopsy cytology. Diagnostic contribution in 100 cases of previously stained, routine specimens.

OBJECTIVE: To assess the contribution of immunocytochemistry (ICC) to aspiration biopsy cytology (ABC), in a diagnostic context, on routine, previously stained cytologic specimens. STUDY DESIGN: Among 5,221 consecutive cases of ABC, 5.3% were subjected to ICC in the clinical-morphologic context. One hundred of these cases, with a final clinical and histopathologic diagnosis, were studied to determine the contribution of this ancillary technique to the final cytologic diagnosis. All cases had histopathologic study and prospective ICC, performed on usual smears, alcohol fixed and previously stained by the Papanicolaou technique, and were subjected to an avidinbiotin-peroxidase complex method. RESULTS: ICC was contributory in 82% of cases. The contribution of ICC to ABC of lymphoid tissue, thyroid and related organs, soft tissue and miscellaneous cases was, respectively, 84% (39 cases), 88% (26), 72% (18) and 76% (17). ICC was noncontributory in 18 cases, due mainly to misleading interpretation (6%), uncharacteristic profile (5%) and inconclusive immunostain (7%). CONCLUSION: ICC could be successfully applied in routine ABC specimens since the usually investigated antigenic determinants are preserved, allowing previous morphologic study and screening of the smears. The principal contribution of ICC applied to lymph nodes, thyroid and soft tissue aspirates was, respectively, confirmation of metastatic neoplasms, differential of follicular versus C-cell proliferation and assessment of mesenchymal lineages.

Adenocarcinoma↗
PubMedDate not supplied

Image analysis of nuclear/cytoplasmic ratio in cervical smears to discriminate three grades of cervical intraepithelial neoplasia.

OBJECTIVE: To suggest which system of cytologic classification (Bethesda System or World Health Organization [WHO]) of cervical lesions is more adequate for the Public Health Service of São Paulo State, Brazil, based on morphometric study with the Jandel Videoanalysis (JAVA) System. STUDY DESIGN: The study comprised groups of typical smears: cervical intraepithelial neoplasia (CIN 1) separated into two subgroups: cytopathic effects of human papillomavirus associated or not with dyskaryosis, CIN 2 and CIN 3. The JAVA system of image analysis was used to determine the nuclear/cytoplasmic (N/C) ratio in abnormal cells from each group. RESULTS: Significant differences were detected between the three grades of CIN and between the two subgroups of CIN 1. CONCLUSION: Although image analysis is not applicable to large-scale population screening of cervical smears, its use in the present study favored the three-grade cytologic classification (WHO). In addition, the three-grade classification offers the clinician more options for treatment. Considering the clinical-laboratory characteristics of our public health service, the three-grade classification is more adequate.

Cell Nucleus↗
PubMedDate not supplied

Adenocarcinoma in females detected in serous effusions. Cytomorphologic aspects and immunocytochemical reactivity to cytokeratins 7 and 20.

OBJECTIVE: To investigate the usefulness of assessing the immunoreactivity of cytokeratins 7 (CK7) and 20 (CK20) as well as several cytomorphologic parameters in effusions with metastatic adenocarcinomas in the search for the primary site of the tumor. STUDY DESIGN: From the files of the Pathology Department, A. C. Camargo Hospital, we studied cytologic smears from 73 metastatic adenocarcinomas originally from the breast, 63 from the ovary, 40 from the lung and 32 from the stomach, looking for morphologic parameters that could have discriminant potential in suggesting the primary site in a routine situation, including intranuclear inclusions, prominent nucleoli, mitosis, signet-ring cells, psammoma bodies, nuclear crease, binucleation and multinucleation, papillary features, acinar profile (including ball cells) and single cells. Immunoreactions were performed with monoclonal antibodies to CK7 (OV-TL 12/30) and CK20 (Ks 20.8) and included morphologic analysis. Both analyses were studied in a blind fashion regarding the primary site of the tumors. RESULTS: Positivity ratios for breast, ovary, stomach and lung cases were 67.6%, 63.5%, 29.7% and 45.5%, respectively, for CK7 and 17.2%, 15.8%, 13.5% and 32.2%, respectively, for CK20. Discriminant analysis of morphologic and immunocytochemical parameters had an error rate of 42.9% in recognizing the primary site and a Wilk's lambda of .7290. CONCLUSION: The more efficient parameter with discriminant function was the papillary appearance showed by CK7, which should be used in further studies with a similar scope. The set of parameters used in this study were insufficient to discriminate the primary site of female adenocarcinomas in effusions with significant accuracy.

Adenocarcinoma↗
PubMedDate not supplied

Cytomorphologic evidence of human papillomavirus infection in smears from the irradiated uterine cervix.

OBJECTIVE: To report the cytomorphologic evidence of human papillomavirus (HPV) infection in cervical smears from women treated with radiotherapy for carcinoma of the uterine cervix. STUDY DESIGN: From January 1986 to December 1993, 32 cervical cytologic smears (CCSs) from women who had received radiotherapy (Rtx) for squamous cell cervical carcinoma at A.C. Camargo Cancer Hospital were selected for study due to the presence of signs of HPV infection. Review of the files of these patients showed 22 additional samples, which we included in this study. The avidinbiotin-immunoperoxidase technique was performed on previously stained slides using polyclonal rabbit antibovine papillomavirus type 1 to confirm the HPV infection. RESULTS: Positive reactions were found in 18 cases (27 samples), mainly in cells with classic koilocytotic features, but also in epithelial cells that lacked cytopathic effects. Only one case, a biopsy from a verrucous lesion observed after Rtx, was found to be positive for HPV 6/11 DNA by in situ hybridization. CONCLUSION: Cytologic and immunohistochemical positivity for HPV, as well as the reaction with a HPV 6/11 DNA probe, strongly suggested that HPV infection was acquired or expressed after radiotherapy. Further studies are needed to assess the mechanisms responsible for such an association.

Adult↗
PubMedDate not supplied

Lactoferrin in thyroid lesions: immunoreactivity in fine needle aspiration biopsy samples.

OBJECTIVE: Lactoferrin is an iron-binding protein that has been used for distinguishing normal from neoplastic conditions in many different tissues. In order to improve evaluation of thyroid lesions, we studied the lactoferrin immunoreaction in cytologic smears obtained by fine needle aspiration and in biopsy samples from primary neoplasms and from adenomatous goiter. STUDY DESIGN: A retrospective study on fine needle aspiration cytology samples and corresponding available biopsies from thyroid lesions in patients examined at São Paulo County Hospital between 1982 and 1992, performed in order to evaluate lactoferrin immunoreactivity in morphologically well characterized samples from neoplastic and nonneoplastic lesions. Immunoperoxidase procedures were performed using monospecific polyclonal rabbit antihuman lactoferrin as a primary antibody and biotinylated goat antirabbit IgG as a secondary antibody. Amplification was performed with the avidin-biotin-peroxidase complex, and the color sign of the positive reactions was developed using a diaminobenzidine solution. RESULTS: Lactoferrin was not detected in cytologic smears from goiters, whereas only one biopsy was slightly positive (1/21, or 4.76%). One smear from adenoma showed low positive staining (1/19, or 5.26%), which was present in 4 of 13 biopsies (30.77%) from adenoma. Papillary carcinomas were positive in 19 of 33 smears (57.58%) and in 100% of biopsies, whereas 31.25% (5/16) of follicular carcinoma smears were positive for lactoferrin, detected in all the biopsy samples. CONCLUSION: Lactoferrin immunoreactivity was strongly associated with neoplastic proliferation and may be used as a useful auxiliary marker to distinguish malignant from benign thyroid lesions in cytologic smears and biopsy samples.

Adenoma↗
PubMedDate not supplied

Predictive factors for response to lamivudine in chronic hepatitis B.

BACKGROUND: Lamivudine has been shown to be an efficient drug for chronic hepatitis B (CHB) treatment. AIM: To investigate predictive factors of response, using a quantitative method with high sensitivity. METHODS: We carried out a prospective trial of lamivudine in 35 patients with CHB and evidence for viral replication, regardless to their HBeAg status. Lamivudine was given for 12 months at 300 mg daily and 150 mg thereafter. Response was considered when DNA was undetectable by PCR after 6 months of treatment. Viral replication was monitored by end-point dilution PCR. Mutation associated with resistance to lamivudine was detected by DNA sequencing in non-responder patients. RESULTS: Response was observed in 23/35 patients (65.7%) but only in 5/15 (33.3%) HBeAg positive patients. Only three pre-treatment variables were associated to low response: HBeAg (p = 0.006), high viral load (DNA-VHB > 3 x 10(6) copies/ml) (p = 0.004) and liver HBcAg (p = 0. 0028). YMDD mutations were detected in 7/11 non-responder patients. CONCLUSIONS: HBeAg positive patients with high viral load show a high risk for developing drug resistance. On the other hand, HBeAg negative patients show a good response to lamivudine even with high viremia.

Adolescent↗
PubMedDate not supplied

Trypanosoma cruzi strains and autonomic nervous system pathology in experimental Chagas disease.

Lesions involving the sympathetic (para-vertebral ganglia) and para-sympathetic ganglia of intestines (Auerbach plexus) and heart (right atrial ganglia) were comparatively analyzed in mice infected with either of three different strain types of Trypanosoma cruzi, during acute and chronic infection, in an attempt to understand the influence of parasite strain in causing autonomic nervous system pathology. Ganglionar involvement with neuronal destruction appeared related to inflammation, which most of the times extended from neighboring adipose and cardiac, smooth and striated muscular tissues. Intraganglionic parasitism was exceptional. Inflammation involving peripheral nervous tissue exhibited a focal character and its variability in the several groups examined appeared unpredictable. Although lesions were generally more severe with the Y strain, comparative qualitative study did not allow the conclusion, under the present experimental conditions, that one strain was more pathogenic to the autonomic nervous system than others. No special tropism of the parasites from any strain toward autonomic ganglia was disclosed.

Animals↗