Publications by authors named "Bernd Buchholz"

During intraerythrocytic development, the human malaria parasite alters the mechanical deformability of its host cell. The underpinning biological processes involve gain in parasite mass, changes in the membrane protein compositions, reorganization of the cytoskeletons and its coupling to the plasma membrane, and formation of membrane protrusions, termed knobs. The hemoglobinopathies S and C are known to partially protect carriers from severe malaria, possibly through additional changes in the erythrocyte biomechanics, but a detailed quantification of cell mechanics is still missing.

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PfEMP1 (erythrocyte membrane protein 1) adhesins play a pivotal role in the pathophysiology of falciparum malaria, by mediating sequestration of -infected erythrocytes in the microvasculature. PfEMP1 variants are expressed by genes and are presented on membrane elevations, termed knobs. However, the organization of PfEMP1 on knobs is largely unclear.

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Sickle cell trait, a common hereditary blood disorder, protects carriers from severe disease in infections with the human malaria parasite . Protection is associated with a reduced capacity of parasitized erythrocytes to cytoadhere to the microvascular endothelium and cause vaso-occlusive events. However, the underpinning cellular and biomechanical processes are only partly understood and the impact on endothelial cell activation is unclear.

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Background: Emergence of resistance against integrase inhibitor raltegravir in human immunodeficiency virus type 1 (HIV-1) patients is generally associated with selection of one of three signature mutations: Y143C/R, Q148K/H/R or N155H, representing three distinct resistance pathways. The mechanisms that drive selection of a specific pathway are still poorly understood. We investigated the impact of the HIV-1 genetic background and population dynamics on the emergence of raltegravir resistance.

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Human herpesvirus-8 (HHV-8) is the etiological agent of Kaposi's sarcoma (KS), which primarily affects human immunodeficiency virus (HIV)-infected adults with advanced immunodeficiency. Currently, only limited prevalence data for HHV-8 infection in HIV-infected children living in non-endemic areas are available. This multicenter cross-sectional study was conducted in four university hospitals in Germany specializing in pediatric HIV care.

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We analyzed a multi-drug resistant (MR) HIV-1 reverse transcriptase (RT), subcloned from a patient-derived subtype CRF02_AG, harboring 45 amino acid exchanges, amongst them four thymidine analog mutations (TAMs) relevant for high-level AZT (azidothymidine) resistance by AZTMP excision (M41L, D67N, T215Y, K219E) as well as four substitutions of the AZTTP discrimination pathway (A62V, V75I, F116Y and Q151M). In addition, K65R, known to antagonize AZTMP excision in HIV-1 subtype B was present. Although MR-RT harbored the most significant amino acid exchanges T215Y and Q151M of each pathway, it exclusively used AZTTP discrimination, indicating that the two mechanisms are mutually exclusive and that the Q151M pathway is obviously preferred since it confers resistance to most nucleoside inhibitors.

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The initial clinical and hematologic presentation of infantile malignant osteopetrosis may be indistinguishable from that of juvenile myelomonocytic leukemia in infants. Timely radiographic imaging, however, allows straightforward delineation of these 2 severe diseases and facilitates immediate initiation of appropriate therapy.

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Abstract High-dose methotrexate (HD-MTX) is an important chemotherapy for various pediatric malignancies. However, in contrast to precise recommendations on supportive care following the start of HD-MTX infusion, studies on the hydration regimen prior to HD-MTX infusion are lacking, and the local standard differs between pediatric oncology centers. Therefore, we prospectively evaluated the relevance of two common prehydration regimens on the clearance and toxicity of MTX in a randomized crossover study.

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Background: HIV-1 seroreversion in infants with vertically transmitted HIV-1 infection who started ART in the first months of life has been reported in only a subset of patients. However, the reason why most infants remain seropositive despite similar treatment response is not understood. Here, we assessed whether HIV-1 seroreversion in maternally infected infants is associated with genetic determinants.

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During the last few decades, the treatment of HIV-infected patients by highly active antiretroviral therapy, including protease inhibitors (PIs), has become standard. Here, we present results of analysis of a patient-derived, multiresistant HIV-1 CRF02_AG recombinant strain with a highly mutated protease (PR) coding sequence, where up to 19 coding mutations have accumulated in the PR. The results of biochemical analysis in vitro showed that the patient-derived PR is highly resistant to most of the currently used PIs and that it also exhibits very poor catalytic activity.

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In Germany during the last years about 200-250 HIV1-infected pregnant women delivered a baby each year, a number that is currently increasing. To determine the HIV-status early in pregnancy voluntary HIV-testing of all pregnant women is recommended in Germany and Austria as part of prenatal care. In those cases, where HIV1-infection was known during pregnancy, since 1995 the rate of vertical transmission of HIV1 was reduced to 1-2%.

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In Germany during the last years about 200-250 HIV infected pregnant women delivered a baby each year, a number that is currently increasing. To determine the HIV-status early in pregnancy voluntary HIV-testing of all pregnant women is recommended in Germany and Austria as part of prenatal care. In those cases, where HIV infection was known during pregnancy, since 1995 the rate of vertical transmission of HIV was reduced to 1-2%.

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In Germany during the past years about 200-250 HIV infected pregnant women delivered a baby per year, a number that is currently increasing. To determine the HIV-status early in pregnancy voluntary HIV-testing of all pregnant women is recommended in Germany and Austria as part of prenatal care. In those cases, where HIV infection was known during pregnancy, since 1995 the rate of vertical transmission of HIV was reduced to 1-2%.

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In 19 young human multiorgan donors, we simultaneously analyzed the bacterial contamination of the kidney perfusion fluid and all retrieved bone allografts. Donor exclusion criteria were done according to the American and European Association of Tissue Banks excluding all patients with perforating wounds. The kidney perfusate revealed a contamination in 17 of 19 (89.

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Anti-retroviral therapy during pregnancy--The German/Austrian recommendations to optimise prevention of vertical transmission of HIV and to minimise adverse drug effects. In Germany during the last years about 200 HIV infected pregnant women delivered a baby each year, a number that is currently increasing. To determine the HIV-status early in pregnancy voluntary HIV-testing of all pregnant women is recommended in Germany and Austria as part of prenatal care.

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