1,721,093 research outputs found

    LYMPHOID DISORDERS ASSOCIATED WITH HHV-8/KSHV INFECTION: FACTS AND CONTENTIONS

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    Following the demonstration in 1994, that Kaposi's sarcoma (KS) was associated with a novel virus (KSHV or HHV-8) belonging to the lymphotropic herpes family, this virus was also found in certain lymphoid neoplasias of immunodeficient (HIV+) and immune competent hosts. The association of HHV-8/KSHV infection is now well established with primary effusion lymphoma (PEL) or body cavity based lymphoma (BCBL) and multicentric Castleman's disease (MCD) of the plasma cell type. A possible pathogenic role of HHV-8/KSHV in other lymphoid tumours including primary central nervous system lymphoma (PCNSL) and multiple myeloma (MM) as well as some atypical lymphoproliferations and sarcoidosis has also been suggested, but this is at present a controversial matter, or not confirmed. Several HHV-8/KSHV genes, including potential oncogenes, genes homologous to various cellular genes and growth factors have been incriminated in the pathogenesis of KS and PEL/BCBL, but a common pathogenic mechanism for the clearly diverse proliferations represented by PEL, MCD and KS is at present not evident

    Malignant lymphomas (ML) and HIV/AIDS Infection in Tanzania.

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    \ud HIV infection is reported to be associated with some malignant lymphomas (ML) so called AIDS-related lymphomas (ARL), with an aggressive behavior and poor prognosis. The ML frequency, pathogenicity, clinical patterns and possible association with AIDS in Tanzania, are not well documented impeding the development of preventive and therapeutic strategies. Sections of 176 archival formalin-fixed paraffin-embedded biopsies of ML patients at Muhimbili National Hospital (MNH)/Muhimbili University of Health and Allied Sciences (MUHAS), Tanzania from 1996-2001 were stained for hematoxylin and eosin and selected (70) cases for expression of pan-leucocytic (CD45), B-cell (CD20), T-cell (CD3), Hodgkin/RS cell (CD30), histiocyte (CD68) and proliferation (Ki-67) antigen markers. Corresponding clinical records were also evaluated. Available sera from 38 ML patients were screened (ELISA) for HIV antibodies. The proportion of ML out of all diagnosed tumors at MNH during the 6 year period was 4.2% (176/4200) comprising 77.84% non-Hodgkin (NHL) including 19.32% Burkitt's (BL) and 22.16% Hodgkin's disease (HD). The ML tumors frequency increased from 0.42% (1997) to 0.70% (2001) and 23.7% of tested sera from these patients were HIV positive. The mean age for all ML was 30, age-range 3-91 and peak age was 1-20 years. The male:female ratio was 1.8:1. Supra-diaphragmatic presentation was commonest and histological sub-types were mostly aggressive B-cell lymphomas however, no clear cases of primary effusion lymphoma (PEL) and primary central nervous system lymphoma (PCNSL) were diagnosed. Malignant lymphomas apparently, increased significantly among diagnosed tumors at MNH between 1996 and 2001, predominantly among the young, HIV infected and AIDS patients. The frequent aggressive clinical and histological presentation as well as the dominant B-immunophenotype and the HIV serology indicate a pathogenic association with AIDS. Therefore, routine HIV screening of all malignant lymphoma patients at MNH is necessary to enable comprehensive ARL diagnosis and formulation of preventive and therapeutic protocols.\u

    Immunohistology of Skin Pathergy Reaction in Behçet's Disease

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    The immunophenotypic characteristics of the skin pathergy reaction (SPR) at 48 h in Behçet's disease (BD) were investigated in 12 patients with BD and in five controls. The findings in 11 positive and one negative SPR lesions of patients with BD were evaluated in comparison with those of normal adjacent skin and with the negative pathergy biopsies from the controls. Positive SPR biopsies showed variable epidermal thickening and cell vacuolization, as well as subcorneal pustule formation. In the SPR dermis, a variable dense focal mononuclear cell (MNC) infiltrate was seen around vessels and skin appendages, extending into the deep dermis. The MNC infiltrate was predominantly composed of T lymphocytes and monocytes/macrophages. The majority of the T lymphocytes were CD4+, and almost all expressed CD45RO. Approximately half of the infiltrating cells strongly expressed HLA-DR. Neutrophils constituted less than 5% of the infiltrating cells, but were present as clusters of elastase-positive cells at the needle-prick sites. Vessels within the lesion showed marked congestion and endothelial swelling. The endothelial cells expressed ICAM-1 strongly, and E-selectin moderately. VCAM-1 was not expressed on endothelial cells. The basal and mid-epidermal layers of keratinocytes expressed HLA-DR and ICAM-1 strongly, particularly so in areas close to the dermal MNC infiltrates. In negative pathergy biopsies, there were increased numbers of neutrophils and a few small clusters of macrophages and T lymphocytes only at the needle-prick site, and the endothelial cells of vessels close to these areas expressed E-selectin weakly. The immunohistological findings of the SPR appear to indicate an augmented antigen-independent non-specific induction phase of the inflammatory response. Absence of VCAM-1 expression by endothelial cells suggests that direct epidermal injury is the cause of the cutaneous inflammation

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Cervical Cytological Changes in HIV-Infected Patients Attending Care and Treatment Clinic at Muhimbili National Hospital, Dar es Salaam, Tanzania.

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    \ud Tanzania is among Sub-Saharan countries mostly affected by the HIV and AIDS pandemic, females being more vulnerable than males. HIV infected women appear to have a higher rate of persistent infection by high risk types of human papillomavirus (HPV) strongly associated with high-grade squamous intraepithelial lesions (HSIL) and invasive cervical carcinoma. Furthermore, although HIV infection and cervical cancer are major public health problems, the frequency and HIV/HPV association of cervical cancer and HSIL is not well documented in Tanzania, thus limiting the development of preventive and therapeutic strategies. A prospective unmatched, case-control study of HIV-seropositive, ≥ 18 years of age and consenting non-pregnant patients attending the care and treatment center (CTC) at Muhimbili National Hoospital (MNH) as cases was done between 2005 and 2006. HIV seronegative, non-pregnant and consenting women recruited from the Cervical Cancer Screening unit (CCSU) at ORCI were used as controls while those who did not consent to study participation and/or individuals under < 18 years were excluded. Pap smears were collected for routine cytodiagnosis and P53 immunohistochemistry (IHC). Cervical lesions were classified according to the Modified Bethesda System. A total of 170 participants from the two centers were recruited including 50 HIV-seronegative controls were from the CCSU. Ages ranged from 20-66 years (mean 40.5 years) for cases and 20-69 years (mean 41.6 years) for controls. The age group 36-45 years was the most affected by HIV (39.2%, n = 47). Cervicitis, squamous intraepithelial lesions (SIL) and carcinoma constituted 28.3% (n = 34), 38.3% (n = 46) and 5.8% (n = 7) respectively among cases, and 28% (n = 14), 34% (n = 17) and 2% (n = 1) for controls, although this was not statistically significant (P-value = 0.61). IHC showed that p53 was not detectable in HPV + Pap smears and cell blocks indicating possible degradation. The frequency of SIL and carcinoma appeared to be higher among HIV-infected women on HAART compared to seronegative controls and as expected increased with age. HIV seropositive patients appeared to present earlier with SIL compared to those HIV seronegative suggesting a role of HIV in altering the natural history of HPV infection and cervical lesions. The absence of p53 immunoreactivity in HPV + lesions is indicative of the ability of HPV E6 proteins to interact with the tumor suppressor gene and pave way for viral-induced oncogenesis in the studied Tanzanian women.\u

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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