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

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.Universidade Federal FluminenseUFF PathologyFundação Oswaldo Cruz Cellular and Molecular BiologyUniversidade Estadual Paulista Júlio de Mesquita Filho Gynecology, Obstetrics and MastologyUniversidade Federal do Rio de Janeiro CardiologyUniversidade Federal de São Paulo (UNIFESP) ObstetricsUNIFESP, ObstetricsSciEL

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

<p>Abstract</p> <p>Background</p> <p>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.</p> <p>Methods</p> <p>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.</p> <p>Results</p> <p>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/mm²in 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/mm²in CIN I: 63.8; CIN II/III: 115.7 and tumor: 112.0, p = 0.005), in comparison to controls.</p> <p>Conclusion</p> <p>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.</p

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

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%) e 75 lesões (56%) no grupo A e 59 pacientes (47%) e 60 lesões (44%) 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%) 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% no grupo A e 10% no B) é significativa (z = 4,60; valor p = 4,2×10-6). Do mesmo modo, a associação HPV-LMP1 (21% no grupo A e 7% 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.<br>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%) and 75 lesions (56%) from group A and 59 patients (47%) and 60 lesions (44%) 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%) showed that the proportions for HPV are not statistically significant (z = 1.93; value p = 0.053). However, the difference (47% in group A and 10% in B) is significant for LMP1 (z = 4.60; value p = 4.2×10-6). Similarly, the association of HPV and LMP1 (21% in group A and 7% 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