FOXP3(+) regulatory and TIA-1(+) cytotoxic T lymphocytes in HIV-associated Hodgkin lymphoma.

Human immunodeficiency virus (HIV) infects CD4(+) lymphocytes, leading to a development of malignant lymphomas, such as HIV-associated Hodgkin Lymphoma (HIV-HL). This study aimed to assess the differences in cellular composition of the inflammatory reactive background of HIV-HLs. We examined infiltrating T lymphocytes, specifically regulatory T cells, cytotoxic cells, Epstein-Barr virus (EBV) related antigens and HIV-receptor CCR5. In all HIV-HL cases, Hodgkin and Reed-Sternberg (HRS) cells showed EBER1 expression, LMP-1 staining positivity and EBNA-2 staining negativity, except for one case which showed LMP-1 staining negativity. Our histological findings indicate the percentage of CD8(+) , TIA-1(+) lymphocytes was significantly higher in HIV-HL than in non-HIV-HL cases (P < 0.05). On the other hand, the percentage of CD4(+) , FOXP3(+) lymphocytes was significantly lower in HIV-HL than in non-HIV-HL cases (P < 0.05) but present. The percentage of CCR5(+) lymphocytes was significantly lower in HIV-HL than in non-HIV-HL cases (P < 0.05). Usually, CD4(+) and CCR5(+) lymphocytes are reported to be rarely detected in HIV-associated non-Hodgkin lymphomas, but the presence of CD4(+) and/or FOXP3(+) lymphocytes may be implicated in the pathogenesis of HL. In addition, although additional CD8(+) lymphocytes are probably not EBV-LMP specific cytotoxic T-cells, these lymphocytes may also well be involved in the pathogenesis of HIV-HL.

Bone marrow pathology in AIDS.

Bone marrow morphology is frequently abnormal in patients with AIDS. In this study, we reviewed 97 bone marrow biopsies of AIDS patients performed between 1998 and 2000 in the Emílio Ribas Institute of Infectology, which is the reference department for HIV. Specific diagnoses were performed in 33 cases. Fungi were observed in eight cases. Five of them were Histoplasma capsulatum, two were Cryptococcus neoformans, and one probably Candida albicans. Acid-fast bacilli were observed in 12 bone marrow biopsies, three of which were diagnosed to have no mycobacteriosis clinically. Foci of necrosis with clusters of macrophages without any well-formed granuloma were observed in nine cases and well-formed granuloma in three cases. Lymphomatous infiltration was observed in four cases of non-Hodgkin's lymphoma and in two Hodgkin's diseases (mixed cellularity). Extensive necrosis of bone marrow was observed in one case of Burkitt's lymphoma. In conclusion, bone marrow biopsy should be performed to elucidate the etiology of cytopenias, secondary infections, and fever of undetermined origin in AIDS patients.

Effects of long-term administration of Senna occidentalis seeds in the large bowel of rats.

Plants of the genus Senna that contain anthranoides derivatives are frequently used as cathartics. Radiological studies have demonstrated that patients with chronic constipation who have used stimulant laxative have colonic redundancy and dilatation more frequently than patients who have not. The objective of the present work was to study morphological and histochemical changes of the lower gut after administration of Senna occidentalis seeds for a long period to rats, as observed in skeletal muscle fibers. Fragments of the lower gut of young and adult rats treated with S. occidentalis seeds (2% for 171 days and 3% for 61 days in the diet) were submitted to histological and histochemical analysis and to densitometry. The most important finding was decreased oxidative enzyme activity in smooth muscle cells and in myenteric neurons of the large bowel. As oxidative metabolism is essential for ATP and energy production, these results suggest that the functional intestinal disturbance caused by the chronic use of Senna occidentalis as a laxative can be due to a metabolic effect involving energy production, which would decrease colonic motility and cause functional colonic dilatation, but without any irreversible anatomic change.

Epstein-Barr Viral Load is Associated to Response in AIDS-Related Lymphomas.

AIDS-related lymphoma (ARL) development is associated to immunodeficiency state with proliferation of B-cells driven by HIV itself and EBV infection. However, Epstein-Barr DNA is not detected in malignant cells of all ARL subtypes. A prospective and controlled study to analyze EBV viral load (VL) in plasma and peripheral blood mononuclear cells (PBMC) of ARL patients was performed to analyze if Epstein-Barr VL could be related to response in these patients. Fifteen patients with ARL were included in this study with measurement of EBV VL at three different periods of time: at lymphoma diagnosis, upon completion of chemotherapy, and 3 months after. Two control groups composed by HIV-negative and HIV-positive patients were also evaluated for EBV VL comparison. In situ hybridization for EBER was performed on diagnostic samples of all ARL patients. Median EBV VL in PBMC and plasma had a significant decrease (p = 0.022 and p = 0.003, respectively) after ARL treatment. EBER was positive in 7 (46.7 %) cases. Median EBV VL in PBMC before lymphoma treatment in patients positive for EBER was significantly higher compared to EBER negative cases (p = 0.041). Reduction of EBV viral load during treatment of lymphoma could be predictive of response. EBER expression was associated to advanced stages of disease and worse immune status. Our study suggests that measurement of EBV VL during ARL treatment could be used as a marker for response, but further studies are needed to validate this association.

Muscle pathology in juvenile dermatomyositis

To study muscle biopsies, using histochemistry, on ten children with infantile dermatomyositis. Design: Series of ten patients (of whom eight patients had received treatment and two had not) were submitted to muscle biopsy in order to diagnose possible inflammatory myopathy or to detect recurrences. Place of development of the study: Public Health Service of Sao Paulo State. Participants: children with clinical features of inflammatory myopathy. Intervention: biopsies were performed on the vastus lateralis using local anesthetic. Histochemistry was performed according to standardized methods. Results: Architectural changes of the muscle fibers, necrosis of variable intensity and accentuated evidence of regeneration were observed in patients who had not received treatment (2 cases) and in one case where muscular weakness persisted in spite of corticosteroid therapy. Necrosis and regeneration were minimal or absent in cases treated for one year or more (4 cases). In 3 cases with clinical and laboratorial recurrences, muscle necrosis and architectural changes were detected. Conclusions: It was concluded that muscle biopsy could aid in diagnosing infantile dermatomyositis as well as in detecting recurrences even in cases without clinical activity of the disease.