Abstract INTRODUCTION: The present study evaluated the epidemiology of cryptococcal meningitis and TNFα gene polymorphisms in patients at a reference hospital in northern Brazil. METHODS: Samples from 25 patients infected with Cryptococcus spp. were collected to confirm the infection and to analyze the TNFα gene polymorphisms. RESULTS: Cryptococcus neoformans was detected as the predominant etiological agent (100%) in HIV-positive patients. No genetic polymorphic changes were found. CONCLUSIONS: No correlation was observed between the analyzed TNFα polymorphisms and cryptococcal meningitis.

Abstract Gastric cancer (GC) remains one of the main causes of cancer-related death worldwide. There are two distinct histological types of GC: diffuse and intestinal. The latter is characterized by the presence of pre-neoplastic lesions. One of the most frequently altered enzymes in intestinal GC is COX-2, an important lesion marker. This work aimed to study COX-2 methylation and expression in N-methyl-N-Nitrosurea (MNU)-induced intestinal GC in six Sapajus apella animals. The partial promoter sequence of S. apella COX-2 gene was obtained and used to identify transcription factors and cis-regulatory element binding sites. The COX-2 methylation pattern was assessed using Methylation-Specific PCR (MSP), and expression was analyzed by immunohistochemistry (IHQ). A total of 20 samples were obtained. A 675 bp fragment of the S. apella COX-2 promoter region was obtained, and it was 99.2% and 68.2% similar to H. sapiens and S. boliviensis, respectively. Similar to humans, several transcription factors and cis-regulatory element binding sites were identified in the S. apella sequence. MSP revealed that all samples were methylated. However, IHQ results demonstrated positive COX-2 expression in all pre-neoplastic and tumoral samples. The results suggest that the analyzed fragment is not crucial in COX-2 regulation of GC in S. apella.

Gastric cancer (GC) is a multifactorial disease with a high mortality rate in Brazil and worldwide. This work aimed to evaluate single nucleotide polymorphisms (SNP) rs1695, in the Glutathione S-Transferase Pi (GSTP1) gene in GC samples by comparative analysis Specific PCR - ASP and Dideoxy Single Allele-Specific PCR - DSASP methods. The DSASP is the proposed new method for allelic discrimination. This work analyzed 60 GC samples, 26 diffuse and 34 intestinal types. The SNP rs1695 of the GSTP1 gene was significantly associated with GC analyzed by DSASP method (χ2 = 9.7, P < 0.05). A comparative analysis of the data obtained from both methods did not differ significantly (χ2 = 0.08, P > 0.05). These results suggest that the SNP rs1695 of the GSTP1 gene was a risk factor associated with gastric carcinogens is and the DSASP method was a new successfully low-cost strategy to study allelic discrimination.

Introduction This study confirmed the absence of natural infection with Xenotropic murine leukemia virus-related virus (XMRV) or XMRV-related disease in human populations of the Brazilian Amazon basin. We demonstrated that 803 individuals of both sexes, who were residents of Belem in the Brazilian State of Pará, were not infected with XMRV. Methods Individuals were divided into 4 subgroups: healthy individuals, individuals infected with human immunodeficiency virus, type 1 (HIV-1), individuals infected with human T-lymphotrophic virus, types 1 or 2 (HTLV-1/2), and individuals with prostate cancer. XMRV infection was investigated by nested PCR to detect the viral gag gene and by quantitative PCR to detect pol. Results There was no amplification of either gag or pol segments from XRMV in any of the samples examined. Conclusions This study supports the conclusions of the studies that eventually led to the retraction of the original study reporting the association between XMRV and human diseases.

Objectives To evaluate the prevalence, distribution and association of HPV with histological pattern of worse prognosis of penile cancer, in order to evaluate its predictive value of inguinal metastasis, as well as evaluation of other previous reported prognostic factors. Material and Methods Tumor samples of 82 patients with penile carcinoma were tested in order to establish the prevalence and distribution of genotypic HPV using PCR. HPV status was correlated to histopathological factors and the presence of inguinal mestastasis. The influence of several histological characteristics was also correlated to inguinal disease-free survival. Results Follow-up varied from 1 to 71 months (median 22 months). HPV DNA was identified in 60.9% of sample, with higher prevalence of types 11 and 6 (64% and 32%, respectively). There was no significant correlation of the histological characteristics of worse prognosis of penile cancer with HPV status. Inguinal disease-free survival in 5 years did also not show HPV status influence (p = 0.45). The only independent pathologic factors of inguinal metastasis were: stage T ≥ T1b-T4 (p = 0.02), lymphovascular invasion (p = 0.04) and infiltrative invasion (p = 0.03). conclusions HPV status and distribution had shown no correlation with worse prognosis of histological aspects, or predictive value for lymphatic metastasis in penile carcinoma.

The frequencies of micronuclei (MN) and morphological nuclear abnormalities (NA) in erythrocytes in the peripheral blood of tambaqui (Colossoma macropomum), treated with 2 mg.L-1 methylmercury (MeHg), were analyzed. Two groups (nine specimens in each) were exposed to MeHg for different periods (group A - 24 h; group B - 120 h). A third group served as negative control (group C, untreated; n = 9). Although, when compared to the control group there were no significant differences in MN frequency in the treated groups, for NA, the differences between the frequencies of group B (treated for 120 h) and the control group were extremely significant (p < 0.02), thus demonstrating the potentially adverse effects of MeHg on C. macropomum erythrocytes after prolonged exposure.

The presence of human papillomavirus (HPV) was evaluated in 65 samples of prostate tumours and six samples of prostates with benign prostatic hyperplasia from individuals from Northern Brazil. We used a highly sensitive test, the Linear Array HPV Genotyping Test, to detect 37 high and low-risk HPV types. In this study, only 3% of tumour samples showed HPV infection. Our findings support the conclusion that, despite the high incidence of HPV infection in the geographic regions studied, HPV was not associated with a higher risk of prostate cancer. To our knowledge, this is the first study evaluating the frequency of HPV detection in prostatic tissue of individuals from Brazil.

Gastric cancer is one of the most common malignancies. DNA methylation is implicated in DNA mismatch repair genes deficiency. In the present study, we evaluated the methylation status of MLH1, MSH2, MSH6 and PMS2 in 20 diffuse- and 26 intestinal-type gastric cancer samples and 20 normal gastric mucosal of gastric cancer patients from Northern Brazil. We found that none of the nonneoplastic samples showed methylation of any gene promoter and 50% of gastric cancer samples showed at least one methylated gene promoter. Methylation frequencies of MLH1, MSH2, MSH6 and PMS2 promoter were 21.74%, 17.39%, 0% and 28.26% respectively in gastric cancer samples. MLH1 and PMS2 methylation were associated with neoplastic samples compared to nonneoplastic ones. PMS2 methylation was associated with diffuse-and intestinal-type cancer compared with normal controls. Intestinal-type cancer showed significant association with MLH1 methylation. Diffuse-type cancer was significantly associated with MSH2 methylation. Our findings show differential gene methylation in tumoral tissue, which allows us to conclude that methylation is associated with gastric carcinogenesis. Methylation of mismatch repair genes was associated with gastric carcinogenesis and may be a helpful tool for diagnosis, prognosis and therapies. However, MSH6 does not seem to be regulated by methylation in our samples.

Physalis angulata L (Solanaceae) is a medicinal plant from North of Brazil, whose different extracts and infusions are commonly used in the popular medicine for the treatment of malaria, asthma, hepatitis, dermatitis and rheumatism. However, the genotoxic effects of P. angulata on human cells is not well known. The main purpose of the present study was to evaluate the in vitro genotoxic effects of aqueous extract of P. angulata using the comet assay and the micronucleus assay in human lymphocytes provided from 6 healthy donors. Treatments with P. angulata extracts were performed in vitro in order to access the extent of DNA damage. The comet assay has shown that treatments with P. angulata at 0.5, 1.0, 2.0, 3.0 and 6.0 μg/mL in culture medium were genotoxic. Lymphocytes treated with P. angulata at the concentrations of 3.0 and 6.0μg/mL in culture medium showed a statistically significant increase in the frequency of micronucleus (p<0.05), however, the cytokinesis blocked proliferation index (CBPI) was not decreased after P. angulata treatment. In conclusion, the present work demonstrated the genotoxic effects of P. angulata extract on human lymphocytes in vitro.

The collared peccary (Tayassu tajacu) is widely distributed over the American continent, being found from the south of the USA to the north of Argentina. In Brazil, it is spread all over the country, being one of the potential species to be raised in captivity. Therefore, the cytogenetic techniques could be a potential tool for reproductive monitoring of animals raised in captivity, mainly when destined for commercial purposes. This study had the objective of determining the chromosome number of two populations raised in captivity and characterizing them by GTG banding. For this purpose, an analysis was made of mitotic metaphases obtained from lymphocyte cultures made from blood samples of 11 animals, six of which from the Northeast and five from the North of Brazil. The results of this analysis showed the same karyotype pattern for the species (2n=30 chromosomes and NF=48), besides corresponding to the South American pattern of the species, i.e., without a translocation between autosomes 1 and 8, chromosome X acrocentric, and no differences were found between the two populations studied. However, chromosomal polymorphisms were observed compared to data from the literature on populations from North and South America.

In the current carcinogenesis models, the occurrence of increasing mutations and selection mechanisms favoring cell survival and higher proliferation rates are taken into account. Epigenetic mechanisms, among which DNA methylation stands out, also take part in oncogenesis. The characteristic of tumor cells that allows the increase of mutations is named genetic instability, encompassing two mechanisms: microsatellite instability, characterized by nucleotide alterations with errors in the DNA repair systems; and chromosomal instability, represented by aberrations occurring in large chromosome segments. Carcinomas are characterized by complex cytogenetic alterations and large gene amalgamations. Telomeric alterations, inadequately repaired DNA breaks, and deficiencies in the mitotic spindle checking systems are events capable of generating the chromosomal instability and aneuploidy which characterize more aggressive neoplasias. A better understanding of the chromosomal instability mechanisms can show the way towards a clinical utilization of such information, like developing more adequate therapeutic strategies, targeted at specific sites involved in the malignization process

Los modelos actuales de carcinogénesis consideran la ocurrencia de mutaciones crecientes y mecanismos selectivos, favoreciendo la sobrevivencia y proliferación celular aumentada. Mecanismos epigenéticos también participan en la oncogénesis, destacando la metilación del DNA. La característica de las células tumorales que permite el aumento de la ocurrencia de mutaciones es denominada inestabilidad genética, donde son identificados dos mecanismos: inestabilidad de microsatélites, caracterizada por alteraciones nucleotídicas con errores en los sistemas de reparación del DNA; inestabilidad cromosómica, en la cual las aberraciones suceden en grandes segmentos cromosómicos. Los carcinomas son caracterizados por alteraciones citogenéticas complejas y grandes mezclas génicas. Alteraciones teloméricas, quiebres de DNA reparados inadecuadamente y deficiencia en los sistemas de chequeo del huso mitótico, son eventos capaces de generar inestabilidad cromosómica y aneuploidía que caracterizan estas neoplasias más agresivas. El conocimiento de los mecanismos que provocan la inestabilidad cromosómica puede permitir la utilización clínica de información en el desarrollo de estrategias terapéuticas más adecuadas, dirigidas a puntos específicos involucrados en procesos de malignización

A linhagem celular Hep-2 é formada por células de carcinoma da laringe e é muito utilizada em modelos de carcinogênese e mutagenêse. Para avaliar o potencial proliferativo desta linhagem, desenvolvemos uma metodologia citogenética (técnica do sobrenadante) para obtenção de metáfases a partir de células que, ao entrarem em mitose, perdem adesão celular, ficando em suspensão no meio de cultura. Através deste procedimento, foram contadas 2000 células, correspondendo a um índice mitótico (IM) de 22.2% . Apesar de o IM obtido por esta técnica não ter sido estatisticamente diferente do IM obtido por outras metodologias citogenéticas clássicas, a técnica do sobrenadante é vantajosa porque elimina o uso de alguns reagentes utilizados na obtenção de metáfases e também diminui o consumo de reagentes de manutenção desta linhagem.

The Hep-2 cell line is derived from laryngeal carcinoma cells and is often utilized as a model in carcinogenesis and mutagenesis tests. To evaluate the proliferative potential of this line, we developed a cytogenetic methodology (drifter technique) to obtain metaphases from cells that loose cellular adhesion when they underwent mitosis in culture. By this procedure, 2000 cells were counted, resulting in a mitotic index (MI) of 22.2%. Although this MI was not statistically different from the one obtained using either a classical cytogenetic method or a cell synchronization technique, the drifter technique has the advantage of not requiring the use of some reagents for the obtention of metaphases and also of diminishing the consumption of maintenance reagents for this cell line.

Hydroxyurea is commonly used in the treatment of myeloproliferative diseases and in patients with sickle cell disease (SCD). The use of this antineoplastic agent in patients with SCD is justified because of the drug's ability to increase fetal hemoglobin levels, thereby decreasing the severity of SCD. However, high doses or prolonged treatment with hydroxyurea can be cytotoxic or genotoxic for these patients, with an increased risk of developing acute leukemia. This danger can be avoided by monitoring the lymphocytes of patients treated with hydroxyurea. Cytogenetic tests are important endpoints for monitoring the physiological effects of physical and chemical agents, including drugs. In this work, we assessed the genotoxicity of hydroxyurea in short-term cultures of lymphocytes from SCD patients. Hydroxyurea was not cytotoxic or genotoxic at the concentrations tested in the G2 phase of the cell cycle. These results support the use of hydroxyurea in the treatment of SCD, although further work is necessary to understand the effects of this drug in vivo.

Chromosome X loss associated with advancing age in women is well stablished in cytogenetics. However, genetic factors involved in this chromosome loss or no disjunction are poorly understood. Apolipoproteins have been associated with chromosome syndromes, such as Trisomy 21 and 18 and their participation in chromosome segregation have been suggested. Apolipoprotein A-IV:360 polymorphism has been associated with cardiovascular diseases, in our population. Twenty four old women, aged 72 to 87 years old selected according to the presence or absence of allele 2 (HIS) were investigated in relation to chromosome X loss. Cytogenetic analysis was performed in interphase lymphocyte nuclei by means of FISH ( Fluorescence In Situ Hibridization) using X centromeric DNA probe. DNA was isolated from blood cells amplified by PCR and digested with Fnu4HI. A higher significant proportion of cells with X chromosome loss was observed in elderly women with allele 2 (HIS) .These results indicate the participation of apolipoprotein A-IV:360 polymorphism in chromosome segregation. The involved mechanisms could be related to oxidative damage related to microcirculation abnormalities and cell death. The biological role of apolipoprotein A-IV on chromosome segregation needs to be further investigated

La pérdida del cromosoma X en mujeres, asociada a la edad avanzada, es un fenómeno ya reconocido hace décadas. Los factores genéticos que llevan a esta pérdida o a la no-disyunción cromosómica, son poco conocidos. Polimorfismos de apolipoproteínas fueron asociados a la ocurrencia de síndromes cromosómicos como las trisomías del 18 y 21 y fue sugerida su participación en la segregación cromosómica. Polimorfismos de la apolipoproteína AIV:360 fueron asociados a molestias cardiovasculares en la población brasileña.Veinticuatro mujeres entre 72 a 87 años, fueron seleccionadas para estudiar la presencia o ausencia del alelo 2 (HIS) y analizar la pérdida del cromosoma X. El análisis citogenético fue realizado en núcleos interfásicos de cultivos de linfocitos por técnica de hibridación in situ con sonda fluorescente centromérica del cromosoma X. El análisis genotípico fue realizado a partir de ADN extraído de la sangre, amplificado por PCR y digerido por la enzima de restricción Fnu4HI. Se observó una proporción significantemente mayor de células con la pérdida del cromosoma X, en mujeres con alelo 2 (HIS). Estos resultados indican la participación del gen de la ApoA-IV en la no-disyunción cromosómica. Los mecanismos de su actuación pueden estar relacionados a daños oxidativos producto de alteraciones en la microcirculación e inducción de muerte celular. La comprensión de este mecanismo todavía necesita de mayor investigación