Gastric adenocarcinoma and Helicobacter pylori: Correlation with p53 mutation and p27 immunoexpression

Introduction: Helicobacter pylori infection is an established risk factor for gastric cancer development, but the exact underlying mechanism still remains obscure. The inactivation of tumor suppressor genes such as p53 and p27(KIP1) is a hypothesized mechanism, although there is no consensus regarding the influence of H. pylori cagA(+) in the development of these genetic alterations. Goals: To verify the relationship among H. pylori infection, p53 mutations and p27(Kip1) Protein (p27) expression in gastric adenocarcinomas (GA) seventy-four tissues were assayed by PCR for H. pylori and cagA presence. Mutational analysis of p53 gene was performed by single-strand conformation polymorphism (SSCP). Seventy tissues were analyzed by an immunohistochemical method for p27 expression. Results: From the samples examined, 95% (70/74) were H. pylori positive, 63% cagA(+). Altered p53 electrophoretic mobility was found in 72% of cases and significantly more frequent in the presence of cagA. Considerable reduction in p27 expression (19%) was found with a tendency for association between cagA(+) and p27(-), although the results were not statistically significant. Concomitant alterations of both suppressor genes were detected in 60% of cases. In the cases cagA(+), 66.7% of them had these concomitant alterations. Conclusions: The data suggest that H. pylori cagA(+) contributes to p53 alteration and indicate that concomitant gene inactivation, with reduced p27 expression, may be a mechanism in which H. pylori can promote the development and progression of gastric cancer. (C) 2010 Elsevier Ltd. All rights reserved.

Uso de la inmunohistoquímica como herramienta epidemiológica para el diagnóstico de rabia bovina a partir de casos no conclusivos

Objective. Identify the rabies virus in cases of nervous disease archived in the laboratory with diagnosis of nonspecific encephalitis. Materials and methods. Twelve samples of bovine brain suspected of rabies, were processed by indirect immunoperoxidase technique using polyclonal antibodies against the viral agent. Results. Was demonstrated the presence of viral antigens in three cases in the form of small aggregates in the cytoplasm of neurons, with a pattern of round or oval and a variable number of viral inclusion bodies. We discussed the importance of the results in Colombia, the usefulness of the technique in the difficult conditions for sending samples to the laboratory, plus the possible relationship of the negative cases with bovine herpesvirus 5. Conclusions. The use of immunohistochemical technique to demonstrate rabies virus antigens in formalin fixed bovines tissues can help in the construction of an epidemiological map of rabies disease in Colombia and may reduce the high under-diagnosis of diseases of the nervous system of cattle, reported in some regions.

COX-2 inhibition decreases VEGF expression and alveolar bone loss during the progression of experimental periodontitis in rats

Background: Vascular endothelial growth factor (VEGF) is a macromolecule of importance in inflammation that has been implicated in periodontitis. The aims of this study were to investigate VEGF expression during the progression of periodontal disease and to evaluate the effect of a preferential cyclooxygenase (COX)-2 inhibitor meloxicam on VEGF expression and alveolar bone loss in experimentally induced periodontitis.Methods: A total of 120 Wistar rats were randomly separated into groups 1 (control) and 2 (meloxicam, 3 mg/kg/day, intraperitoneally, for 3, 7, 14, or 30 days). Silk ligatures were placed at the gingival margin level of the lower right first molar of all rats. VEGF expression was assessed by reverse transcription-polymerase chain reaction (RT-PCR), Western blot (WB), and immunohistochemical (IHC) analyses. The hemiarcades were processed for histopathologic analysis. RT-PCR and WB results were submitted to analysis of variance, the Tukey test, and Pearson correlation analysis (P<0.05).Results: A reduction in alveolar bone resorption was observed in the meloxicam-treated group compared to the control group at all periods studied. There was a positive correlation between COX-2 mRNA and VEGF mRNA in the gingival tissues and periodontal disease (R = 0.80; P = 0.026). Meloxicam significantly reduced the increased mRNA VEGF expression in diseased tissues after 14 days of treatment (P = 0.023). Some alterations in VEGF receptor I mRNA expression were observed, but these were not statistically significant. VEGF protein expression in WB experiments was significantly higher in diseased sites compared to healthy sites (P<0.05). After 14 days of treatment with meloxicam, an important decrease in VEGF protein expression was detected in diseased tissues (P = 0.08). Qualitative IHC analysis revealed that VEGF protein expression was higher in diseased tissues and decreased in tissues from rats treated with meloxicam.Conclusions: The present data suggest an important role for VEGF in the progression of periodontal disease. Systemic therapy with meloxicam can modify the progression of experimentally induced periodontitis in rats by reducing VEGF expression and alveolar bone loss.

Leishmania chagasi infection in cats with dermatologic lesions from an endemic area of visceral leishmaniosis in Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Evaluation of the microvascular density in astrocytomas in adults correlated using SPECT-MIBI

Microvascular density (MVD) may be an additional prognostic marker for astrocytomas, but the heterogeneity of these tumors limits its use. Thus, imaging examinations such as SPECT-MIBI (2-methoxyisobutyl isonitrile) may take on an indirect role in astrocytoma evaluation. The aim of this study was to evaluate MVD in astrocytomas using immunohistochemistry with anti-CD34 monoclonal antibodies. The relationship between the immunohistochemical data and the parameters obtained from SPECT-MIBI was evaluated. This cross-sectional study evaluated 48 patients with brain tumors including low-grade astrocytomas (LGAs), anaplastic astrocytomas (AAs) and glioblastoma multiformes (GBMs). Patients had been admitted to the Hospital de Cancer de Barretos - Fundação Pio XII, and underwent brain SPECT-MIBI prior to any treatment. MVD was determined under an optical microscope by counting microvessels on slides from each case. SPECT-MIBI images were analyzed visually and semiquantitatively. GBMs, AAs and LGAs represented 50, 16.7 and 33.3% of the total sample, respectively. There were 13 normal and 35 abnormal SPECT-MIBI images. Significant differences in MVD were found between AA and LGA cases (p=0.040), but not between normal and abnormal SPECT-MIBI. The mean counts from SPECT-MIBI were not correlated with MVD. Among the GBM cases, there were no significant findings, except for an increased likelihood of abnormal histological test results. MVD was related to histological grade (in AA and LGA cases) but was not correlated with SPECT-MIBI.

Detection of T lymphocytes in intestine of broiler chicks treated with Lactobacillus spp. and challenged with Salmonella enterica serovar enteritidis

The expression of immune response in the form of leukocytic infiltrate by CD3+, CD4+, and CD8+ cells in the epithelium and in the intestinal lamina propria of chicks was studied in the present work by means of immunohistochemical reaction. The chicks were treated with Lactobacillus spp. or cecal microflora (CM) and experimentally challenged or not with Salmonella enterica serovar Enteritidis. The 320 birds utilized were divided into 4 groups containing 80 chicks each and submitted to treatments with Lactobacillus reuteri, Lactobacillus salivarius, Lactobacillus acidophilus, and CM. Each group was subdivided into 4 subgroups of 20 birds each and classified into a subgroup that did not receive treatment (negative control), subgroup treated, subgroup treated and challenged with Salmonella Enteritidis, and subgroup only challenged with Salmonella Enteritidis (positive control). The results obtained show that the treatment with L. reuteri, L. salivarius, L. acidophilus, or CM and challenged or not with Salmonella Enteritidis determine immune response in the form of leukocytic infiltrate by CD3+ and CD8+ lymphocytes followed by CD4+ in the epithelium and in the lamina propria of the duodenum, jejunum, and cecum of chicks up to 12 d of age. The quantity of CD3+ lymphocytes was significantly higher (P < 0.05) in the intestine of chicks treated with L. acidophilus or CM and challenged or not with Salmonella Enteritidis; however, the higher quantity of CD8+ lymphocytes was in the intestine of chicks treated with CM and challenged with Salmonella Enteritidis. The duodenum was the segment in which the immune response by T cells (CD3+, CD4+, and CD8+) was stimulated with the greatest intensity, followed by, respectively, the jejunum and cecum. The quantity of CD3+ lymphocytes present in the duodenum, jejunum, and cecum increases with the age of chicks, independent of the stimulus determined by treatments or challenge.

Conventional and Doppler ultrasound for the differentiation of benign and malignant canine mammary tumours

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Myenteric Denervation Downregulates Galectin-1 and-3 Expression in Gastric Carcinogenesis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Selective Ablation of the Androgen Receptor in Mouse Sertoli Cells Affects Sertoli Cell Maturation, Barrier Formation and Cytoskeletal Development

The observation that mice with a selective ablation of the androgen receptor (AR) in Sertoli cells (SC) (SCARKO mice) display a complete block in meiosis supports the contention that SC play a pivotal role in the control of germ cell development by androgens. To delineate the physiological and molecular mechanism responsible for this control, we compared tubular development in pubertal SCARKO mice and littermate controls. Particular attention was paid to differences in SC maturation, SC barrier formation and cytoskeletal organization and to the molecular mediators potentially involved. Functional analysis of SC barrier development by hypertonic perfusion and lanthanum permeation techniques and immunohistochemical analysis of junction formation showed that SCARKO mice still attempt to produce a barrier separating basal and adluminal compartment but that barrier formation is delayed and defective. Defective barrier formation was accompanied by disturbances in SC nuclear maturation (immature shape, absence of prominent, tripartite nucleoli) and SC polarization (aberrant positioning of SC nuclei and cytoskeletal elements such as vimentin). Quantitative RT-PCR was used to study the transcript levels of genes potentially related to the described phenomena between day 8 and 35. Differences in the expression of SC genes known to play a role in junction formation could be shown from day 8 for Cldn11, from day 15 for Cldn3 and Espn, from day 20 for Cdh2 and Jam3 and from day 35 for ZO-1. Marked differences were also noted in the transcript levels of several genes that are also related to cell adhesion and cytoskeletal dynamics but that have not yet been studied in SC (Actn3, Ank3, Anxa9, Scin, Emb, Mpzl2). It is concluded that absence of a functional AR in SC impedes the remodeling of testicular tubules expected at the onset of spermatogenesis and interferes with the creation of the specific environment needed for germ cell development.

Interleukin-8 expression associated with canine mammary tumors

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Adenocarcinoma polimorfo de baixo grau de malignidade do tipo papilífero. Estudo morfológico e imuno-histoquímico.

Two cases of polymorphous low-grade adenocarcinoma of the papillary type, from minor salivary glands were studied by light microscopy and immunohistochemistry. One case exhibited a predominance of the papillary pattern, whereas the other presented the following patterns of histological appearance: papillary, solid, pseudocystic and tubular. Utilizing the peroxidase-antiperoxidase (PAP) method, the intermediate filament vimentin, keratin and S100 protein were observed in tumor cells. The immunohistochemical analysis revealed two types of neoplastic cells: myoepithelial and luminal.

Utilidade dos métodos imuno-histoquímicos para o diagnóstico anátomo-patológico.

In order to determine the value of immunohistochemical staining methods for the morphologic diagnosis, we studied 949 histologic specimens sent for consultation to the Immunohistochemistry Laboratory of Department of Pathology of the Medical School of Botucatu in the period 1984-1989. All case were submitted to the immunoperoxidase staining with the methods PAP or ABC. Immunohistochemical stains confirmed the original morphologic diagnosis in 468 cases (49.3%); made the definitive diagnosis from a list of differential diagnostic possibilities in 244 cases (25.7%); provided contributory information in 74 cases (7.8%); were non-contributory in 114 cases (12%) and rendered an unsuspected diagnosis in 49 cases (5.2%). In some cases with non-contributory information the differences in methods of fixation might have led to suboptimal preservation of tissue antigens. The immunohistochemical staining may provide important and sometimes essential informations for definitive diagnosis. This technique was particularly useful for differential diagnosis between carcinoma, lymphoma and melanoma.

Renal interstitial foam cells are macrophages

Immunohistochemical studies on renal biopsies from eight patients with various types of glomerulonephritis showed that the interstitial foam cells belonged to the monocyte-macrophage lineage. There was a strong association between hypercholesterolaemia and the presence of renal interstitial foam cells.

Contribuição do estudo imuno-histoquímico para o diagnóstico anátomo-patológico.

In order to determine the value of immunohistochemical staining methods for morphologic diagnosis specimens of 949 cases received at the Immunohistochemistry Laboratory of the Department of Pathology of the Medical School of Botucatu, in the period 1984-1989 were reviewed. All of them were submitted to the immunoperoxidase staining (PAP or ABC). The main morphologic diagnosis was confirmed in 468 cases (49.3%); the definitive diagnosis was made in 244 cases (25.7%) that had only differential diagnosis, and contributory information was provided in 74 cases (7.8%); the immunohistochemical staining was non-contributory in 114 cases (12%). It rendered an unsuspected diagnosis in 49 cases (5.2%). The analysis of these cases shows that immunohistochemical methods may provide important and sometimes essential informations for definitive diagnosis. This technique is particularly useful for distinguishing between carcinoma, lymphoma and melanoma.

Considerações sobre o câncer localmente avançado de mama (CLAM) acrescidas de identificação dos receptores de estrogênios usando anticorpos monoclonais.

The effects of therapy in locally advanced breast cancer submitted to combined conventional telecobalt therapy plus chemotherapy with cyclophosphamide and 5-fluorouracil were studied in 49 patients. Associated to radical mastectomy in operable cases. Local tumor control was achieved in 86.7%. There were no local recurrences in those submitted to surgery but they reached 21.7% in inoperable patients who received only radiation therapy and chemotherapy. The median follow-up time for dead patients was 29.5 months and for living patients 79.3 months. The index of complete responses was 24.5% and the median disease free interval was 22.9 months. The overall survival rate, between three and five years, was 32.7%. Estrogen receptors were identified by using immunohistochemical assay ER-ICA and monoclonal antibody H222-SP gamma, Abbott. There were no differences in the complete response index, disease free interval and survival rates, among ER-positive and ER-negative patients, explained by the far advanced stage of the disease. ER-positivity was significantly correlated with histological features of the tumors: cell differentiation, presence of elastosis, absence of lymphocytic infiltration and absence of tumor necrosis.