Biomedical subjects

Paula Yurie Tanaka

Publications and source records attributed to Paula Yurie Tanaka.

4 recordsLinked to original sources

PubMed2006

P-glycoprotein expression in non-Hodgkin's lymphomas of human immunodeficiency virus infected patients.

Multidrug resistance (MDR) is a challenge in cancer treatment. One of the most studied mechanisms is P-glycoprotein (P-gp), which acts as a drug efflux pump, with decreased intracellular accumulation of drugs. It still needs to be clarified whether P-gp expression has a significant impact on non-Hodgkin's lymphoma treatment response, but a poor outcome has been reported in patients with positive P-gp expression. AIDS-related lymphomas have aggressive behavior, and although a complete response could be achieved, relapse is not uncommon. In an attempt to determine a possible relationship between MDR and poor outcome in this population, histologic samples obtained from 45 non-Hodgkin's lymphoma HIV-infected patients without previous cytotoxic therapy were submitted to immunohistochemical analysis using monoclonal antibody C494 specific for the MDR-1 isoform of P-gp. Samples from 27 patients (60%) were positive. Response to treatment (P=0.02) and overall survival (P=0.001) were significantly lower in patients with positive P-gp expression. In patients having achieved complete remission, the median disease-free survival (DFS) was not reached; the mean DFS was 57.2 months with DFS rates of 72.9% in three years. Our results show that P-gp is expressed before treatment of non-Hodgkin's lymphoma of HIV patients, and is related to poor response to treatment and overall survival.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2006

Bone marrow biopsy in the diagnoses of infectious and non-infectious causes in patients with advanced HIV infection.

AIMS: Fever and peripheral blood abnormalities in patients with advanced acquired immunodeficiency syndrome are usually due to disseminated opportunistic infections. The objective of this study was to evaluate the diagnostic yield of histopathological and microbiological investigations of bone marrow samples from HIV-infected patients with fever and/or cytopenias. METHODS AND RESULTS: The diagnostic utility of bone marrow aspiration, biopsy and culture was retrospectively examined in 82 patients with HIV/AIDS (median CD4 count 51 microL(-1), range 1-430 microL(-1)) with peripheral cytopenias and/or fever attended at a large tertiary care hospital in Brazil during a one-year period. The diagnostic yield of bone marrow biopsy was 34.1% (28 cases) in contrast to only 8.5% (eight cases) attained by the bone marrow smear. Opportunistic pathogens were isolated from bone marrow cultures in 26.8% of patients. CONCLUSIONS: Bone marrow biopsy has value in diagnosis of opportunistic infections, malignancies or other conditions in one-third of adult patients with advanced AIDS and fever or cytopenias and should be considered in this patient group.

AIDS-Related Opportunistic Infections↗

PubMed2006

Non-Hodgkin's lymphoma among patients infected with human immunodeficiency virus: the experience of a single center in Brazil.

The relative risk of non-Hodgkin's lymphoma (NHL) among patients infected with human immunodeficiency virus (HIV) is elevated compared with the general population. We describe a retrospective study of 78 HIV-infected patients with NHL treated between 1999 and 2006 at the Infectology Institute, a reference center for HIV treatment in São Paulo, Brazil. All patients were treated with standard CHOP therapy (cyclophosphamide, doxorubicin, vincristine, and prednisone). An evaluation of treatment response was available for 48 (61.5%) of the patients who completed initial treatment. Twenty-three patients (47.9%) achieved a complete response (CR), 3 (6.3%) achieved a partial response, and 22 (45.8%) failed to respond to treatment. Of the 30 patients (38.5%) who were not available for response evaluation, 23 died of sepsis during treatment, 5 abandoned treatment, and 2 are still under treatment. After a median follow-up of 3 years, the overall survival rate for all patients is 20.5%. A univariate analysis showed a significant CR rate in patients with respect to the following factors: no acquired immunodeficiency syndrome (AIDS) diagnosis prior to the lymphoma, disease stage of I to II, and an International Prognostic Index (IPI) of low or low-intermediate risk. A multivariate analysis indicated that only a previous AIDS diagnosis and the IPI were significantly related to the CR rate. A median disease-free survival (DFS) time for the patients who achieved a CR was not reached, with a mean survival time of 73 months and a 3-year DFS rate of 77.5%. Our results provide additional information regarding HIV-related lymphoma in Brazil.

Adolescent↗

PubMed2004

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.

AIDS-Related Opportunistic Infections↗