Dengue infection in pregnancy and its impact on the placenta.

A histopathological and immunohistochemical study was conducted in placental tissues and retained products of conception from 24 patients with confirmed dengue infection during pregnancy. The immunohistochemical assay was positive for dengue virus in 19 placental and three ovular remnants analyzed. The light microscopic findings were signs of hypoxia, choriodeciduitis, deciduitis and intervillositis and the viral antigens were found in cytoplasmic of the trophoblast, villous stroma and decidua. Our results suggest that immunohistochemistry could be used as a laboratory confirmation method for dengue in pregnant women, especially in endemic areas when embedded material is the only material available.

Anatomopathological characterization of placentas from HIV+ patients associated with p24 expression / Caracterização anatomopatológica da placenta de pacientes HIV+ associada à expressão do p24

INTRODUCTION: The study of placentas from pregnant human immunodeficiency virus (HIV) positive women has become the subject of numerous studies in the literature. Morphological, viral, immune and inflammatory placental aspects have been analyzed in order to grasp the vertical transmission of the virus. OBJECTIVE: To identify the most frequent findings in the placentas by associating them with a viral antigen and correlating them with the infection of newborns. MATERIAL AND METHODS: Thirty-five placentas from HIV- positive pregnant women were pathologically and immunohistochemically analyzed with the use of p24 antibody in the period from 1992 to1997 in accordance with the routine laboratory testing from the Anatomopathological Department - Hospital Universitário Antônio Pedro - Universidade Federal Fluminense (APD/HUAP/UFF). RESULTS: The microscopic alterations detected in all cases, including those with vertical transmission, were arteriopathy in the fetal blood circulation, chorioamnionitis, perivillous fibrin deposition, syncytial knotting, villous edema and villous immaturity. No specific macroscopic or histopathological changes were found in these placentas. The neonatal infection was observed in five cases. Vertical transmission was identified in two out of five placentas that had low weight for the respective stage of pregnancy. Immunohistochemical analysis revealed 14 positive cases, two of which showed vertical transmission. The viral protein was not identified in 10 out of 14 placentas from patients who had been medicated with zidovudine (AZT). CONCLUSION: Our study has contributed to the anatomopathological investigation into placentas from HIV-positive patients, although p24 expression per se did not allow a definite and early diagnosis of the vertical transmission.

INTRODUÇÃO: A importância do estudo da placenta de gestantes com o vírus da imunodeficiência humana (HIV) soropositivas tornou-se alvo de inúmeros trabalhos na literatura. Aspectos morfológicos, virais, imunes e inflamatórios intrínsecos ao tecido placentário foram analisados para o entendimento da transmissão vertical do vírus. OBJETIVO: Identificar as lesões mais frequentes nas placentas, associando-as ao antígeno viral e correlacionando-as com a infecção dos recém-nascidos. MATERIAL E MÉTODOS: Trinta e cinco placentas de gestantes HIV soropositivas foram analisadas por estudo anatomopatológico e imuno-histoquímico, utilizando o anticorpo p24, no período de 1992 a 1997, segundo a rotina do laboratório do Serviço Anatomia Patológica/Hospital Universitário Antônio Pedro/Universidade Federal Fluminense (SAP/HUAP/UFF). RESULTADOS: As alterações microscópicas registradas em todos os casos, inclusive nos de transmissão vertical, foram arteriopatia no circuito vascular fetal, corionamnionite, depósito fibrinoide perivilositário, excesso de nós sinciciais, edema do estroma viloso e dismaturidade vilosa. Nenhuma alteração microscópica ou macroscópica específica do HIV foi encontrada nas placentas. A infecção neonatal pôde ser constatada em cinco casos. A transmissão vertical foi identificada em duas placentas entre cinco que tinham baixo peso para a idade gestacional. Análise da imuno-histoquímica do p24 mostrou 14 casos positivos, dois dos quais apresentaram transmissão vertical. A proteína viral não foi identificada em 10 das 14 placentas cujas pacientes foram medicadas com zidovudina (AZT). CONCLUSÃO: Nosso estudo contribuiu para o estudo anatomopatológico da placenta de pacientes soropositivas para o HIV, porém a expressão do p24 por si só não permitiu um diagnóstico definitivo e precoce da transmissão vertical.

Imunoexpressão das proteínas COX-2, p53 e caspase-3 em adenoma colorretal e mucosa não neoplásica / Immunoexpression of the COX-2, p53, and caspase-3 proteins in colorectal adenoma and non-neoplastic mucosa

OBJETIVO: Analisar a imunoexpressão das proteínas COX-2, p53 e caspase-3 em adenomas colorretais e na mucosa não neoplásica. MÉTODOS: Foram submetidos à colonoscopia 72 indivíduos que forneceram 50 amostras de adenomas e 45 de mucosa colorretal não neoplásica. Os tecidos foram obtidos pela técnica de arranjo em matriz (tissue microarray) e submetidos a estudo imunoistoquímico com anticorpos primários p53, COX-2 e caspase-3. A positividade e intensidade da imunorreação foram classificadas. Foram estudadas as seguintes variáveis: localização do adenoma no colo, grau de displasia, tamanho, e escores de positividade e intensidade da imunoexpressão das proteínas p-53, caspase-3 e COX-2. RESULTADOS: Nos adenomas, a imunoexpressão da proteína p53 mutada foi positiva em 30 (60%) e negativa em 20 (40%) amostras. Na mucosa colorretal não neoplásica, a imunoexpressão da proteína p53 mutada foi negativa em 39 (86,6%) amostras e positiva em 6 (13,3%) (p<0,0001). Houve diferença significativa entre o maior tamanho (p=0,006) e o maior grau de displasia dos adenomas (p<0,0001) e a intensidade de imunoexpressão da proteína p53 mutada. A positividade e intensidade da imunoexpressão das proteínas COX-2 (p=0,14) e caspase-3 (p=0,23), nos adenomas e na mucosa colorretal não neoplásica, não apresentaram diferença significante. CONCLUSÃO: A proteína p53 mutada é hiperexpressada nos adenomas em comparação com a mucosa não neoplásica. Nos adenomas, o maior tamanho e o maior grau de displasia foram associados à maior expressão da proteína p53 mutada. A imunoexpressão das proteínas COX-2 e caspase nos adenomas não apresentou correlação com os aspectos anatomopatológicos e não foi diferente em termos de níveis de expressão correspondentes na mucosa não neoplásica.

OBJECTIVE: To analyze the immunoexpression of the COX-2, p53, and caspase-3 proteins in colorectal adenomas and non-neoplastic mucosa. METHODS: 72 individuals were subjected to colonoscopy, which provided 50 samples of adenomas and 45 samples of non-neoplastic colorectal mucosa. The tissue samples were obtained via the tissue microarray technique and subjected to immunohistochemical analysis using primary anti-p53, anti-COX-2, and anti-caspase-3 antibodies. The positivity and intensity of the immunoreaction were classified. The analyzed variables were as follows: site of the adenomas in the colon, degree of dysplasia, size, and score of positivity and intensity of immunoexpression of the p-53, caspase-3, and COX-2 proteins. RESULTS: The immunoexpression of mutated protein p53 was positive in 30 (60%) adenoma samples and negative in 20 (40%) adenoma samples. The immunoexpression of mutated protein p53 was negative in 39 (86.6%) samples and positive in 6 (13.3%) samples of the non-neoplastic colorectal mucosa (p<0.0001). Significant differences were seen between both the largest size (p=0.006) and the highest degree of dysplasia (p<0.0001) of the adenomas and the intensity of immunoexpression of mutated protein p53. The positivity and intensity of immunoexpression of COX-2 (p=0.14) and caspase-3 (p=0.23) showed no significant differences between the adenomas and the non-neoplastic colorectal mucosa. CONCLUSION: Mutated protein p53 was hyperexpressed in the adenomas compared with the non-neoplastic mucosa. Greater size and greater degree of dysplasia in the adenomas were associated with higher expression of mutated protein p53. The immunoexpression of COX-2 and caspase-3 in the adenomas did not exhibit a correlation with the anatomical-pathological features of the tumors and did not differ from the corresponding expression levels in the non-neoplastic mucosa.

Tamoxifen decreases the myofibroblast count in the healing bile duct tissue of pigs.

OBJECTIVE: The aim of this study was to evaluate the effect of oral tamoxifen treatment on the number of myofibroblasts present during the healing process after experimental bile duct injury. METHODS: The sample consisted of 16 pigs that were divided into two groups (the control and study groups). Incisions and suturing of the bile ducts were performed in the two groups. Tamoxifen (20 mg/day) was administered only to the study group. The animals were sacrificed after 30 days. Quantification of myofibroblasts in the biliary ducts was made through immunohistochemistry analysis using anti-alpha smooth muscle actin of the smooth muscle antibody. Immunohistochemical quantification was performed using a digital image system. RESULTS: In the animals treated with tamoxifen (20 mg/day), there was a significant reduction in immunostaining for alpha smooth muscle actin compared with the control group (0.1155 vs. 0.2021, p = 0.046). CONCLUSION: Tamoxifen reduced the expression of alpha smooth muscle actin in the healing tissue after bile duct injury, suggesting a decrease in myofibroblasts in the scarred area of the pig biliary tract. These data suggest that tamoxifen could be used in the prevention of biliary tract stenosis after bile duct surgeries.

Tamoxifen decreases the myofibroblast count in the healing bile duct tissue of pigs

OBJECTIVE: The aim of this study was to evaluate the effect of oral tamoxifen treatment on the number of myofibroblasts present during the healing process after experimental bile duct injury. METHODS: The sample consisted of 16 pigs that were divided into two groups (the control and study groups). Incisions and suturing of the bile ducts were performed in the two groups. Tamoxifen (20 mg/day) was administered only to the study group. The animals were sacrificed after 30 days. Quantification of myofibroblasts in the biliary ducts was made through immunohistochemistry analysis using anti-alpha smooth muscle actin of the smooth muscle antibody. Immunohistochemical quantification was performed using a digital image system. RESULTS: In the animals treated with tamoxifen (20 mg/day), there was a significant reduction in immunostaining for alpha smooth muscle actin compared with the control group (0.1155 vs. 0.2021, p = 0.046). CONCLUSION: Tamoxifen reduced the expression of alpha smooth muscle actin in the healing tissue after bile duct injury, suggesting a decrease in myofibroblasts in the scarred area of the pig biliary tract. These data suggest that tamoxifen could be used in the prevention of biliary tract stenosis after bile duct surgeries.

Immunoexpression of the COX-2, p53, and caspase-3 proteins in colorectal adenoma and non-neoplastic mucosa.

OBJECTIVE: To analyze the immunoexpression of the COX-2, p53, and caspase-3 proteins in colorectal adenomas and non-neoplastic mucosa. METHODS: 72 individuals were subjected to colonoscopy, which provided 50 samples of adenomas and 45 samples of non-neoplastic colorectal mucosa. The tissue samples were obtained via the tissue microarray technique and subjected to immunohistochemical analysis using primary anti-p53, anti-COX-2, and anti-caspase-3 antibodies. The positivity and intensity of the immunoreaction were classified. The analyzed variables were as follows: site of the adenomas in the colon, degree of dysplasia, size, and score of positivity and intensity of immunoexpression of the p-53, caspase-3, and COX-2 proteins. RESULTS: The immunoexpression of mutated protein p53 was positive in 30 (60%) adenoma samples and negative in 20 (40%) adenoma samples. The immunoexpression of mutated protein p53 was negative in 39 (86.6%) samples and positive in 6 (13.3%) samples of the non-neoplastic colorectal mucosa (p<0.0001). Significant differences were seen between both the largest size (p=0.006) and the highest degree of dysplasia (p<0.0001) of the adenomas and the intensity of immunoexpression of mutated protein p53. The positivity and intensity of immunoexpression of COX-2 (p=0.14) and caspase-3 (p=0.23) showed no significant differences between the adenomas and the non-neoplastic colorectal mucosa. CONCLUSION: Mutated protein p53 was hyperexpressed in the adenomas compared with the non-neoplastic mucosa. Greater size and greater degree of dysplasia in the adenomas were associated with higher expression of mutated protein p53. The immunoexpression of COX-2 and caspase-3 in the adenomas did not exhibit a correlation with the anatomical-pathological features of the tumors and did not differ from the corresponding expression levels in the non-neoplastic mucosa.

Evaluation of liver regeneration by modulation with ischemic preconditioning after ischemia and reperfusion and partial hepatectomy.

OBJECTIVE: To evaluate liver regeneration modulated by ischemic preconditioning after ischemia, reperfusion and partial hepatectomy. METHODS: We used 24 Wistar rats of 12 weeks of age, which were randomly assigned into four groups: control (SHAM), hepatectomy (HEP), ischemia and reperfusion (IRG) and Ischemic Preconditioning (SRG). Analyses were made on liver enzymes ALT and AST, assessment of regeneration through the initial and final weight of the liver and the proliferation of hepatocytes by immunohistochemical analysis with Proliferating Cell Nuclear Antigen (PCNA). RESULTS: In all groups there was liver regeneration, with no statistically significant difference between them. There were significant differences in ALT and AST between groups HEP and SHAM, PRE and GIR, GIR and SHAM and PRE and SHAM (p <0.05). There were also significant differences in the PCNA labeling of the SHAM group as compared to other groups (p <0.05). CONCLUSION: The ischemic preconditioning decreased liver injury, but did not influence the regeneration up to 48 hours.

Avaliação da regeneração hepática com modulação pelo pré-condicionamento isquêmico após isquemia e reperfusão e hepatectomia parcial / Evaluation of liver regeneration by modulation with ischemic preconditioning after ischemia and reperfusion and partial hepatectomy

OBJETIVO: Avaliar a regeneração hepática com modulação pelo pré-condicionamento isquêmico após isquemia, reperfusão e hepatectomia parcial. MÉTODOS: Foram usadas 24 ratas Wistar, de 12 semanas de idade, distribuídas randomicamente em quatro grupos: Grupo Controle (SHAM), Grupo Hepatectomia (HEP), Grupo Isquemia e Reperfusão (GIR) e Grupo Pré-condicionamento Isquêmico (PRE). Foi feita a análise das enzimas hepáticas ALT e AST, avaliação da regeneração através dos pesos inicial e final do fígado e da proliferação dos hepatócitos pela análise imunoistoquímica com o Proliferating Cell Nuclear Antigen (PCNA). RESULTADOS: Em todos os grupos ocorreu regeneração do fígado, não havendo significância estatística entre eles. Houve diferenças significativas em relação a ALT e AST entre os grupos HEP-SHAM, GIR-PRE, GIR-SHAM E PRE-SHAM (p< 0,05). Também houve diferença significativa em relação à marcação de PCNA do grupo SHAM quando comparado aos demais grupos (p< 0,05). CONCLUSÃO: O pré-condicionamento isquêmico diminuiu a lesão hepática, mas não influenciou na regeneração até 48 horas.

OBJECTIVE: To evaluate liver regeneration modulated by ischemic preconditioning after ischemia, reperfusion and partial hepatectomy. METHODS: We used 24 Wistar rats of 12 weeks of age, which were randomly assigned into four groups: control (SHAM), hepatectomy (HEP), ischemia and reperfusion (IRG) and Ischemic Preconditioning (SRG). Analyses were made on liver enzymes ALT and AST, assessment of regeneration through the initial and final weight of the liver and the proliferation of hepatocytes by immunohistochemical analysis with Proliferating Cell Nuclear Antigen (PCNA). RESULTS: In all groups there was liver regeneration, with no statistically significant difference between them. There were significant differences in ALT and AST between groups HEP and SHAM, PRE and GIR, GIR and SHAM and PRE and SHAM (p <0.05). There were also significant differences in the PCNA labeling of the SHAM group as compared to other groups (p <0.05). CONCLUSION: The ischemic preconditioning decreased liver injury, but did not influence the regeneration up to 48 hours.

Parvovirose e anemia acentuada em paciente imunocompetente / Parvovirus and severe anemia in an immunocompetent patient

Paciente de 16 anos, sexo masculino, com vírus da imunodeficiência humana (HIV) negativo e sem doença hematológica prévia, desenvolveu anemia acentuada devido à infecção por parvovírus B19. A doença apresentou evolução bifásica, com acalmia clínica e retorno dos sintomas após 15 dias. Ao exame físico, apresentava-se descorado e febril, sem adeno e organomegalias, com sinais de insuficiência cardíaca. O aspirado de medula óssea mostrava megaloblastos com nucléolos aberrantes e, na histologia, foram observadas células gigantes com nucleolação aberrante e presença do corpúsculo de inclusão nuclear típico da parvovirose. O exame de imuno-histoquímica mostrou positividade para anticorpo específico para parvovírus. A sorologia comprovou a infecção.

A 16-year-old human immunodeficiency virus (HIV) negative male patient without hematological disease developed acute anemia due to parvovirus B19 infection. The disease showed a biphasic evolution: clinical remission and return of symptoms after 15 days. Physical examination revealed paleness and fever, neither adeno nor organomegalies, and signs of heart failure. The bone marrow aspiration showed megaloblasts with aberrant nucleoli. As far as histology is concerned, giant cells with aberrant nucleoli and the presence of intranuclear inclusions typical of Parvoviruses were observed. Immunohistochemistry revealed positivity for specific Parvovirus antibody. Serology confirmed parvovirus B19 infection.

Validação de construção de tissue microarray para estudo da displasia intraepitelial tubular renal / Validation of tissue microarray technique for intratubular epithelial dysplasia study

INTRODUÇÃO E OBJETIVO: O carcinoma de células renais (CCR) é umas das doenças urológicas de maior malignidade, correspondendo a 1 por cento-3 por cento de todos os tumores sólidos dos adultos. As lesões pré-malignas do CCR ainda não foram totalmente descritas. Achados de displasia intraepitelial tubular renal (DIETR) em áreas próximas ao tumor, livres de neoplasia, sugerem que esta alteração possa ser a precursora biológica de alguns tipos de CCR. O objetivo deste estudo é avaliar a possibilidade do uso de tissue microarray (TMA) no estudo da DIETR e do CCR e os parâmetros para sua utilização imuno-histoquímica (IHQ) utilizando os anticorpos anti-Ki-67 e p53 para confirmar a evidência de DIETR como precursora biológica do CCR. MATERIAL E MÉTODOS: O estudo foi realizado em 10 peças cirúrgicas de nefrectomias realizadas em pacientes com diagnóstico de CCR selecionadas no período de 2000 a 2005, em material arquivado no Instituto Nacional de Câncer (INCA). DISCUSSÃO: A utilização da técnica de TMA permite amostragem de várias áreas e realização da IHQ utilizando apenas duas lâminas, uma para cada marcador. Como não há na literatura descrição de utilização de TMA para estudo da DIETR, foi necessário inicialmente realizar estudo de validação para saber se haveria representatividade de lesões focais no TMA. RESULTADOS: A análise estatística não mostrou diferença entre a utilização de TMA com dois ou quatro cilindros de tecido ou o corte inteiro. CONCLUSÃO: O teste de validação de técnica artesanal de TMA autorizou o uso de dois cilindros de 1 mm² por caso.

INTRODUCTION AND OBJECTIVE: Renal cell carcinoma is one of the most malignant urological diseases, corresponding to 1 percent-3 percent of solid tumors in adults. The finding of intratubular epithelial dysplasia (IED) next to tumor areas suggests that this can be the biological precursor of some types of renal cell carcinoma (RCC). The objective of this study is to evaluate the use of tissue microarray (TMA) to study IED and RCC by immunohistochemistry (IHC) with Ki-67 and p53 protein to confirm the evidence that IED is the biological precursor of RCC. MATERIAL AND METHOD: This study was performed in archival material from ten nephrectomy surgical specimens from Instituto Nacional de Câncer, between 2000 and 2005. DISCUSSION: TMA technique allows to sample and study several different areas from many patients in the same slide, using just one slide for each IHC marker. Once there was no previous study on IED by TMA, a validation test was needed first. RESULTS: There was no statistical difference between 2 or 4 tissue cores and the whole section analysis. CONCLUSION: TMA validation assay demonstrated that the use of two tissue cores with 1 mm² each was suitable to evaluate RCC and IED.

The benefits of using selenium in the treatment of Chagas disease: prevention of right ventricle chamber dilatation and reversion of Trypanosoma cruzi-induced acute and chronic cardiomyopathy in mice.

Cardiac damage is a frequent manifestation of Chagas disease, which is caused by the parasite Trypanosoma cruzi. Selenium (Se) is an essential micronutrient, the deficiency of which has been implicated in the development of cardiomyopathy. Our group has previously demonstrated that Se supplementation prevents myocardial damage during acute T. cruzi infection in mice. In this study, we analyzed the effect of Se treatment in cases of T. cruzi infection using prevention and reversion schemes. In the Se prevention scheme, mice were given Se supplements (2 ppm) starting two weeks prior to inoculation with T. cruzi(Brazil strain) and continuing until 120 days post-infection (dpi). In the Se reversion scheme, mice were treated with Se (4 ppm) for 100 days, starting at 160 dpi. Dilatation of the right ventricle was observed in the infected control group at both phases of T. cruzi infection, but it was not observed in the infected group that received Se treatment. Surviving infected mice that were submitted to the Se reversion scheme presented normal P wave values and reduced inflammation of the pericardium. These data indicate that Se treatment prevents right ventricular chamber increase and thus can be proposed as an adjuvant therapy for cardiac alterations already established by T. cruzi infection.

Investigação da LMP1 do EBV e a coinfeçcão do HPV em lesões genitais de pacientes infectados ou não pelo HIV / Investigation of the LMP1 EBV and co-infection by HPV in genital lesions of patients infected or not by HIV

INTRODUÇÃO: Vários estudos têm demonstrado associação do vírus Epstein-Barr (EBV) com neoplasias malignas, inclusive genitais, em que o papilomavírus humano (HPV) é o principal vírus associado às neoplasias epiteliais benignas e malignas. OBJETIVO: Investigar a presença do EBV e do HPV em lesões genitais de ambos os sexos, em pacientes soropositivos (grupo A) ou não (grupo B) para o vírus da imunodeficiência humana (HIV). MATERIAL E MÉTODO: Selecionados 126 pacientes e 135 lesões anogenitais, sendo 67 pacientes (53 por cento) e 75 lesões (56 por cento) no grupo A e 59 pacientes (47 por cento) e 60 lesões (44 por cento) no grupo B, para análise imuno-histoquímica (IHQ) por meio dos anticorpos monoclonais antiproteína latente de membrana 1 (LMP1) e HPV (DAKO®). RESULTADOS: A análise mostrou que o número total de lesões com imunopositividade para o HPV e para a LMP1 foi maior no grupo A (32 e 35, respectivamente) quando comparado ao B (16 e seis, respectivamente). A análise estatística (nível de significância de 5 por cento) mostrou que as proporções para o HPV não são estatisticamente significativas (z = 1,93; valor p = 0,053). Entretanto, para a LMP1, a diferença (47 por cento no grupo A e 10 por cento no B) é significativa (z = 4,60; valor p = 4,2×10-6). Do mesmo modo, a associação HPV-LMP1 (21 por cento no grupo A e 7 por cento no B) também mostrou diferença estatisticamente significativa (z = 2,38; valor p = 0,017). CONCLUSÃO: Esses resultados indicam a possibilidade de sinergismo da infecção pelo EBV e a coinfecção EBV-HPV em lesões epiteliais genitais, particularmente em pacientes soropositivos para o HIV. Entretanto, investigações com metodologia de maior especificidade e sensibilidade são necessárias para a verificação da real participação do EBV na patogênese de lesões epiteliais genitais.

INTRODUCTION: Several studies have demonstrated the association between Epstein-Barr virus (EBV) and malignant neoplasias, including genital lesions, in which the human papillomavirus (HPV) is the main virus associated with both benign and malignant epithelial neoplasias. OBJECTIVE: Investigate the presence of EBV and HPV in genital lesions in HIV-infected patients (group A) or HIV non-infected patients (group B) from both genders. MATERIAL AND METHOD: We selected 126 patients and 135 anogenital lesions, comprising 67 patients (53 percent) and 75 lesions (56 percent) from group A and 59 patients (47 percent) and 60 lesions (44 percent) from group B, to histopathological and immunohistochemical analyses through latent membrane protein 1 (LMP1) monoclonal antibodies and HPV (DAKO®). RESULTS: The analysis showed that the total number of lesions with immunopositivity for HPV and for LMP1 was higher in group A (32 and 35 respectively) in comparison with B (16 and six respectively). Statistical analysis (significance level of 5 percent) showed that the proportions for HPV are not statistically significant (z = 1.93; value p = 0.053). However, the difference (47 percent in group A and 10 percent in B) is significant for LMP1 (z = 4.60; value p = 4.2×10-6). Similarly, the association of HPV and LMP1 (21 percent in group A and 7 percent in B) also showed a significant statistical difference (z = 2.38; value p = 0.017). CONCLUSION: The results demonstrated the possibility of synergism between EBV infection and EBV-HPV co-infection in genital epithelial lesions, mainly among HIV-infected patients. However, further investigations with a more specific and sensitive methodology are required in order to assess the real influence of EBV on the pathogenesis of genital epithelial lesions.

The benefits of using selenium in the treatment of Chagas disease: prevention of right ventricle chamber dilatation and reversion of Trypanosoma cruzi-induced acute and chronic cardiomyopathy in mice

Cardiac damage is a frequent manifestation of Chagas disease, which is caused by the parasite Trypanosoma cruzi. Selenium (Se) is an essential micronutrient, the deficiency of which has been implicated in the development of cardiomyopathy. Our group has previously demonstrated that Se supplementation prevents myocardial damage during acute T. cruzi infection in mice. In this study, we analyzed the effect of Se treatment in cases of T. cruzi infection using prevention and reversion schemes. In the Se prevention scheme, mice were given Se supplements (2 ppm) starting two weeks prior to inoculation with T. cruzi(Brazil strain) and continuing until 120 days post-infection (dpi). In the Se reversion scheme, mice were treated with Se (4 ppm) for 100 days, starting at 160 dpi. Dilatation of the right ventricle was observed in the infected control group at both phases of T. cruzi infection, but it was not observed in the infected group that received Se treatment. Surviving infected mice that were submitted to the Se reversion scheme presented normal P wave values and reduced inflammation of the pericardium. These data indicate that Se treatment prevents right ventricular chamber increase and thus can be proposed as an adjuvant therapy for cardiac alterations already established by T. cruziinfection.

Hypodermic needle without recipient paraffin block technique.

This technique allows building TMA blocks with more than 300 tissue cores without using a recipient paraffin block for the tissue cores and without using a commercial TMA builder instrument. It is based on the construction of TMA needles modifying conventional hypodermic needles to punch tissue cores from donor blocks. Tissue cores are punctured from donor blocks and attached by double-sided adhesive tape on a computer-generated paper grid used to align the cores on the block mold, which is filled with liquid paraffin. TMA blocks constructed using this method can be utilized as positive and negative controls for immunohistochemistry, histochemistry and other techniques, interlaboratory quality control and also in research, but never for diagnosis purposes. This technique has the following advantages: it is easy to reproduce, affordable, quick, and creates uniform blocks with more than 300 cores aligned, at the same plane, adherent, and easy to cut, with negligible losses during conventional cutting and technical procedures.

Cell-cycle and suppressor proteins expression in uterine cervix in HIV/HPV co-infection: comparative study by tissue micro-array (TMA).

BACKGROUND: The oncoproteins of human papillomavirus (HPVs) directly effect cell-cycle control. We hypothesize that regulatory and cell cycle protein expression might be additionally modified in the cervix of HIV/HPV co-infected women. METHODS: We analyzed the expression of Rb, p27, VEGF and Elf-1 transcriptor factor by immunohistochemistry in 163 paraffin-embeded cervical samples using Tissue Micro-Array (TMA) and correlated this to HIV-1 and HPV infection. RESULTS: HIV/HPV co-infection was associated with a significant increase in expression (p < 0.001) of VEGF and p27 in both low and high grade CIN when compared to the cervices of women infected by HPV alone. Decreased Rb expression was evident with increased CIN grade in the cervices of women infected with HPV alone (p = 0.003 average of cells/mm2 in CIN I: 17.9, CIN II/III: 4.8, and tumor 3.9). Rb expression increased 3-fold for both low and high grade CIN with HPV/HIV-1 co-infection compared to HPV infection alone but did not reach statistical significance. There was a significant increase in Elf-1 expression in HPV+/HIV- women with CIN II/III and tumor (average of cells/mm2 in CIN I: 63.8; CIN II/III: 115.7 and tumor: 112.0, p = 0.005), in comparison to controls. CONCLUSION: Co-infection of HPV and HIV leads to significant increase in the VEGF and p27 expression when compared to HPV+/HIV-negative infection that could facilitate viral persistence and invasive tumor development.

Histologic, viral, and molecular correlates of dengue fever infection of the liver using highly sensitive immunohistochemistry.

The mechanism by which the virus associated with dengue fever can cause a fatal hepatitis is not well understood. The purpose of this study was to examine 9 cases of fatal dengue hemorrhagic fever-associated hepatitis, and to correlate the histologic findings with viral detection and cytokine response. The histologic changes were nonspecific and included massive hepatic necrosis and a pauci-cellular acute hepatitis. Viral cDNA detection by reverse transcriptase in situ polymerase chain reaction demonstrated that the fatal hepatitis was due to infection on average of >90% of hepatocytes and many Kupffer cells. Similar results were obtained using immunohistochemistry for viral protein using an automated highly sensitive system. Immunohistochemical analysis for tumor necrosis factor alpha, and interleukin-2, showed rare positive Kupffer cells. In comparison, fatal cases of hepatitis C associated liver failure demonstrated far fewer infected hepatocytes and a concomitant strong up-regulation of many cytokines, notably tumor necrosis factor alpha and interleukin-2. It is concluded that fatal dengue hemorrhagic fever is associated with acute, severe liver damage due primarily to massive direct infection of hepatocytes and Kupffer cells with minimal cytokine response. The infection can be readily detected in a few hours using an automated system that has a sensitivity equivalent to reverse transcriptase in situ polymerase chain reaction.

TMA for all: a new method for the construction of tissue microarrays without recipient paraffin block using custom-built needles.

BACKGROUND: TMAs are becoming a useful tool for research and quality control methods, mostly for immunohistochemistry and in situ hybridization. METHODS: A new technique that allows building TMA blocks with more than 300 tissue cores without using a recipient paraffin block for the tissue cores and without using a commercial TMA builder instrument is described. This technique is based on the construction of TMA needles modifying conventional hypodermic needles to punch tissue cores from donor blocks, which are attached by double-side adhesive tape on a computer-generated paper grid used to align the cores on the block mould, which is filled with liquid paraffin. RESULTS: More than two hundred TMA blocks were constructed using this method, utilized in immunohistochemistry and histochemistry as positive and negative controls and also in research. CONCLUSION: This technique has the following advantages: it is easy to reproduce, affordable, quick and creates uniform blocks with more than 300 cores aligned, adherent and easy to cut, with negligible losses during cutting and immunohistochemistry and in situ hybridization procedures.

Ceratoacantoma: aspectos imuno-histoquímicos diferenciais do Carcinoma de Células escamosas

O ceratoacantoma é um tumor cutâneo de crescimento rápido, composto de células escamosas ceratinizadas que apresenta achados clínicos e histopatógicos em comum com o carcinoma de células escamosas (CCE) cutâneo, tornando, às vezes, difícil o diagnóstico diferencial para o patologista. Relatos de lesões de aspecto clássico, clíncia e histopatologicamente, exibindo comportamento biológico agressivo, com invasão tumoral e metástases, têm sugerido que a ceratoacantoma pode ser considerado um tipo de CCE. O objetivo foi analisar as diferenças imuno-histoquímicas entre o ceratoacantoma e o CCE cutâneo. Foram estudados 14 casos de ceratoacantoma e 12 casos de CCE. Foram realizadas técnicas imuno-histoquímicas, utilizando anticorpos monoclonais para PCNA, p53 e Bcl-2. Dentre os casos de ceratoacantoma, 13 (92 por cento) mostratam positividade maior para PCNA na região da camada basal ou periférica de massas tumorais, enquanto no CCE foi encontrada positividade variável entre a camada basal e o interior dos ninhos, sugerindo diferenças no modelo de expressão do PCNA entre esses tumores. Todos os casos avaliados demonstraram imunorreação negativa para o proto-oncogenese Bcl-2. De forma semelhante ao PCNA, a marcação para p53(gene supressor tumoral) também se mostrou maior na camada basal do que no interior do tumor, na maioria dos casos de ceratoacantoma, diferentemente dos casos de CCE, onde a mairoria apresentou positividade semelhante entre a área periférica e o interior da neoplasia. A análise dos resultados sugere que a positividade para PCNA e p53 maior no interior da massa tumoral do que na periferia invadida o dignóstico de ceratoacantoma. A positividade para p53 e PCNA se mostrou de forma semelhante entre o ceratoacantoma e o CCE bem diferenciado, apontando para uma aproximação do comportamento biológico desses tumores