Resumen La evaluación de la expresión del ligando 1 de muerte programada (PD-L1) es un criterio de elegibilidad para la inmunoterapia anti-PD-L1 en el carcinoma oral de células escamosas (COCE). También deben evaluarse otros componentes del microambiente tisular. Aquí se informaron cuatro casos de carcinoma de células escamosas orales. Se realizaron análisis histopatológicos del grado tumoral y TIL (infiltrado inflamatorio asociado a tumor) e inmunohistoquímica para CD4, CD8 y PD-L1. Los casos se clasificaron según el microambiente tisular en resistencia inmunitaria adaptativa, ignorancia inmunológica, tolerancia o inducción intrínseca. Este análisis destaca la importancia de comprender el microambiente inmunológico que puede presentar el COCE para la identificación de dianas terapéuticas más eficaces contra la enfermedad.

Abstract The evaluation of the expression of programmed cell death protein (PD-L1) is an eligibility criterion for anti-PD-L1 immunotherapy in oral squamous cell carcinoma (OSCC). Other components of tissue microenvironment should also be evaluated. Here, four cases of oral squamous cells carcinoma were reported. Histopathological analysis of tumor grade and TILs and immunohistochemistry for CD4, CD8, and PD-L1 was done. The cases were classified according to the tissue microenvironment in adaptive immune resistance, immunological ignorance, tolerance, or intrinsic induction. This analysis highlights the importance of understanding the immunological microenvironment that the OSCC can present for the identification of more effective therapeutic targets against the disease.

The Piper species chemistry has been widely investigated and the phytochemical analyses have led to the isolation of a number of active compounds like alkaloids, terpenes and flavones among others. The aim of this study was to evaluate the leishmanicidal activity of 2-[1-hydroxy-3-phenyl-(Z,2E)-2-propenylidene]-4-methyl-4-cyclopentene-1,3-dione (DCPC), a cyclopentenedione derivative isolated from the roots of Piper carniconnectivum C. DC., Piperaceae. Leishmanicidal activity against Leishmania amazonensis promastigotes was assessed, and the risk to host cell was assessed by measuring the cytotoxicity to peritoneal macrophages from BALB/c mice in vitro. L. amazonensis promastigotes and host macrophages were cultured in the presence of 100, 50, 25, 12.5 and 6 µg/mL of the cyclopentenedione derivative for up to 96 h. At the end of this period, the inhibitory concentrations (IC50) were compared with those from untreated cultures. The IC50 for promastigotes was 4.4 µg/mL after 96 h of treatment with the derivative. The 50% cytotoxic concentration (CC50) against murine peritoneal macrophages was 129 µg/mL. These results indicate that DCPC is a promising molecule for the development of leishmanicidal drugs.

A colonização do colo e reto por espiroquetas intestinais foi detectada pela primeira vez no Brasil em 4 de 282 (1,41%) pacientes submetidos a sigmoidoscopia e/ou colonoscopia com o diagnóstico histopatológico de colite crônica inespecífica. A frequência é provavelmente menor que a real, urna vez que espécimens cirúrgicos não foram considerados no presente estudo. O diagnóstico histopatológico foi feito através de colorações de rotina, tais como a hematoxilina-eosina, que mostraram franja basofílica de 3µ de espessura sobre a borda em escova do epitélio e por impregnações pela prata como o método de Whartin-Starry. Métodos imunohistoquímicos, usando dois soros primários policlonais, um contra o Treponema pallidum e o outro contra Leptospira interrogans, serovar copenhageni serogrupo Icterohaemorrhagiae revelaram reatividade cruzada com os antígeno/s dos espiroquetas produzindo um contraste acentuado da franja sobre o epitélio colônico e preservando a morfologia espiralada do parasita. Em um paciente, com acentuada diarréia, a imunohistoquímica detectou antígenos de espiroqueta no citoplasma de uma célula da cripta intestinal, demonstrando que a infecção estava mais disseminada do que parecia pelas colorações comuns. Portanto, os métodos imunohistoquímicos facilitam o diagnóstico histológico da espiroquetose intestinal e podem , também, contribuir para a melhor compreensão da patogenia da doença. A microscopia eletrônica de transmissão e a microscopia de varredura, realizadas em um paciente, demonstraram que os espiroquetas lembram a espécie designada como Brachyspira aalborgi.

Colonization of the colon and rectum by intestinal spirochetes is detected for the first time in Brazil in 4 of 282 (1.41%) patients who had undergone sigmoidoscopy and/or colonoscopy with a histopathological diagnosis of chronic non specific-colitis. This frequency is probably understimated, since surgically obtained specimens were not considered in the present study. Histopathological diagnosis was performed using routine stains like hematoxylin-eosin which showed the typical, of 3-µm thick hematoxyphilic fringe on the brush border of the surface epithelium, and by silver stains like the Warthin-Starry stain. Immunohistochemical procedures using two, polyclonal, primary antibodies, one against Treponema pallidum and the other against Leptospira interrogans serovar copenhageni serogroup Icterohaemorrhagiae cross-reacted with spirochetal antigen/s producing a marked contrast of the fringe over the colonic epithelium, preserving the spiral-shaped morphology of the parasite. In one case with marked diarrhea, immunohistochemistry detected spirochetal antigen/s within a cell in an intestinal crypt, thus demonstrating that the infection can be more widely disseminated than suspected using routine stains. Immunohistochemical procedures, thus, greatly facilitate the histological diagnosis of intestinal spirochetosis and may contribute to a better understanding of the pathogenesis of the disease. Transmission and scanning electron microscopy performed in one case showed that the spirochete closely resembled the species designated as Brachyspira aalborgi.