SDS-CGE of proteins in microchannels made of SU-8 films.

This work describes the SDS-CGE of proteins carried out in microchannels made of the negative photoresist EPON SU-8. Embedded electrophoretic microchannels have been fabricated with a multilayer technology based on bonding and releasing steps of stacked SU-8 films. This technology allows the monolithic integration of the electrodes in the device.

Decreased metalloproteinase production as a response to mechanical pressure in human cartilage: a mechanism for homeostatic regulation.

Articular cartilage is optimised for bearing mechanical loads. Chondrocytes are the only cells present in mature cartilage and are responsible for the synthesis and integrity of the extracellular matrix. Appropriate joint loads stimulate chondrocytes to maintain healthy cartilage with a concrete protein composition according to loading demands.

Successful rescue therapy with darunabir (TMC114) in HIV-infected patients who have failed several ritonavir-boosted protease inhibitors.

Darunabir, formerly TMC114, is a new protease inhibitor (PI) under clinical development designed to be active against HIV strains resistant to currently available PI. The virological and immunological response to ritonavir-boosted darunabir was assessed in four heavily antiretroviral-experienced patients who had failed enfuvirtide and two or more previous ritonavir-boosted PI regimens, including tipranavir in one instance. All four patients reached undetectable plasma HIV-RNA levels within 8 weeks of therapy and experienced significant CD4 cell count gains.

Follicular dendritic cells are related to bone marrow stromal cell progenitors and to myofibroblasts.

Follicular dendritic cells (FDC) are involved in the presentation of native Ags to B cells during the secondary immune response. Some authors consider FDC to be hemopoietic cells, whereas others believe them to be mesenchymal cells. The low proportion of FDC in the lymphoid follicle, together with technical difficulties in their isolation, make these cells difficult to study.

Folding and aggregation kinetics of a beta-hairpin.

We have investigated the solution structure, equilibrium properties, and folding kinetics of a 17-residue beta-hairpin-forming peptide derived from the protein ubiquitin. NMR experiments show that at 4 degrees C the peptide has a highly populated beta-hairpin conformation. At protein concentrations higher than 0.

Higher risk of hyperglycemia in HIV-infected patients treated with didanosine plus tenofovir.

The combination of didanosine (ddI) and tenofovir (TDF) has potential advantages, but because of several pitfalls (unexpected decreases in CD4+ T cells, increased risk of pancreatitis) its use has been questioned. Since anecdotal cases of transient insulin-dependent diabetes mellitus were seen in our clinic in patients on ddI + TDF-containing regimens, we explored the rate of this complication in more detail. Retrospective analysis of plasma glucose levels in patients who completed 12 months of treatment with three different triple antiretroviral regimens including ddI + TDF, TDF, or ddI was done.

Hereditary hemorrhagic telangiectasia, a vascular dysplasia affecting the TGF-beta signaling pathway.

Hereditary hemorrhagic telangiectasia (HHT) is caused by mutations in endoglin (ENG; HHT1) or ACVRL1/ALK1 (HHT2) genes and is an autosomal dominant vascular dysplasia. Clinically, HHT is characterized by epistaxis, telangiectases and arteriovenous malformations in some internal organs such as the lung, brain or liver. Endoglin and ALK1 proteins are specific endothelial receptors of the transforming growth factor (TGF)-beta superfamily that are essential for vascular integrity.

Enhanced antiangiogenic therapy with antibody-collagen XVIII NC1 domain fusion proteins engineered to exploit matrix remodeling events.

Antiangiogenic therapy is nowadays one of the most active fields in cancer research. The first strategies, aimed at inhibiting tumor vascularization, included upregulation of endogenous inhibitors and blocking of the signals delivered by angiogenic factors. But interaction between endothelial cells and their surrounding extracellular matrix also plays a critical role in the modulation of the angiogenic process.

Engineering of large numbers of highly specific homing endonucleases that induce recombination on novel DNA targets.

The last decade has seen the emergence of a universal method for precise and efficient genome engineering. This method relies on the use of sequence-specific endonucleases such as homing endonucleases. The structures of several of these proteins are known, allowing for site-directed mutagenesis of residues essential for DNA binding.

Multiple parosteal lipoma associated to polyarthritis.

Parosteal lipoma is a benign adipose tissue tumor situated directly in the bone cortex. All cases previously reported in the literature were described as solitary lesions. We describe a patient who presented with polyarthritis associated with multiple parosteal lipomatous involvement.

Mitochondrial dysfunction in osteoarthritis.

In osteoarthritis (OA) a time or age dependent process leads to aberrant cartilage structure which is characterized by reduced number of chondrocytes, loss of existing cartilage extracellular matrix, the production of matrix with abnormal composition and pathologic matrix calcification. Because chondrocyte matrix synthesis and mineralization are modulated by the balance between ATP generation and consumption, the mechanism by which chondrocytes generate energy have been a topic of interest. The analysis of mitochondrial respiratory chain (MRC) activity in OA chondrocytes shows a significant decrease in complexes II and III compared to normal chondrocytes.

Proteomic characterization of human normal articular chondrocytes: a novel tool for the study of osteoarthritis and other rheumatic diseases.

Articular cartilage is composed of cells and an extracellular matrix. The chondrocyte is the only cell type present in mature cartilage, and it is important in the control of cartilage integrity. There is currently a great lack of knowledge about the chondrocyte proteome.

Paradoxical CD4+ T-cell decline in HIV-infected patients with complete virus suppression taking tenofovir and didanosine.

Background: Tenofovir (TDF) and didanosine (ddI) are both adenosine analogues with convenient posology, strong potency and a relatively high genetic barrier for resistance. The popularity of this combination, however, has been questioned due to concerns about pharmacokinetic interactions and increased risk of pancreatitis and hyperglycemia. Less information is available about other possible side effects.

Interaction and functional interplay between endoglin and ALK-1, two components of the endothelial transforming growth factor-beta receptor complex.

Transforming growth factor-beta (TGF-beta) signaling in endothelial cells is able to modulate angiogenesis and vascular remodeling, although the underlying molecular mechanisms remain poorly understood. Endoglin and ALK-1 are components of the TGF-beta receptor complex, predominantly expressed in endothelial cells, and mutations in either endoglin or ALK-1 genes are responsible for the vascular dysplasia known as hereditary hemorrhagic telangiectasia. Here we find that the extracellular and cytoplasmic domains of the auxiliary TGF-beta receptor endoglin interact with ALK-1 (a type I TGF-beta receptor).

Short communication: benefits in the lipid profile after substitution of abacavir for Stavudine: a 48-week prospective study.

Stavudine (d4T) has been associated with lipoatrophy and hyperlactatemia. In recent studies, d4T has also been related to both hypercholesterolemia and hypertriglyceridemia. Replacing d4T with another nucleoside analogue such as abacavir (ABC) may reduce lactate levels and improve lipoatrophy in the long term.

Pig chondrocyte xenoimplants for human chondral defect repair: an in vitro model.

The objective of this study was to evaluate the use of cultured porcine chondrocyte xenotransplantation for the repair of human chondral defects. Two-millimeter-diameter defects were drilled into explants of femoral cartilage from healthy adult donors. No cells were implanted in the chondral defects of the control group, while pig chondrocytes from normal femoral cartilage were deposited into the treated chondral defects.

Xeno-implantation of pig chondrocytes into rabbit to treat localized articular cartilage defects: an animal model.

Articular cartilage has only a limited ability to regenerate. The transplantation of autologous chondrocytes is currently used to treat focal defects in human articular cartilage, although use of organs, tissues, or cells from different species is being investigated as an alternative treatment. The object of this study was to use xeno-transplantation of cultured pig chondrocytes for the repair of rabbit chondral defects, and to analyze the significance of tissue rejection in this animal model.

Solution structure of the hypothetical protein Mth677 from Methanobacterium thermoautotrophicum: a novel alpha+beta fold.

The structure of Mth677, a hypothetical protein from Methanobacterium thermoautotrophicum (Mth), has been determined by using heteronuclear nuclear magnetic resonance (NMR) methods on a double-labeled (15)N-(13)C sample. Mth677 adopts a novel alpha+beta fold, consisting of two alpha-helices (one N terminal and one C terminal) packed on the same side of a central beta-hairpin. This structure is likely shared by its three orthologs, detected in three other Archaebacteria.

Changes in mitochondrial DNA copy number in blood cells from HIV-infected patients undergoing antiretroviral therapy.

Mitochondrial DNA (mtDNA) copy number was measured in peripheral blood mononuclear cells (PBMCs) from 69 individuals using a real-time NASBA quantitative assay. Patients with HIV infection harbored significantly lower mtDNA copy number in PBMC than HIV-negative controls. Besides, subjects on stavudine-containing regimens showed significantly lower median mtDNA amounts than HIV-positive patients receiving other antiretroviral drugs, and this was associated with higher lactate levels.

Hydroxyurea plus didanosine as maintenance therapy for HIV-infected patients on long-term successful highly active antiretroviral therapy.

Background: Toxicity and quality of life issues have moved to delay the initiation of highly active antiretroviral therapy (HAART) and to explore novel treatment strategies for HIV infection. The switch to simpler regimens or treatment discontinuation has been attempted with limited success. The combination of hydroxyurea (HU) plus didanosine (ddI) is a simple regimen that might be able to restrain virus replication for long periods of time and could be an acceptable option as maintenance therapy in patients on prolonged successful HAART.

Correlation between lopinavir plasma levels and lipid abnormalities in patients taking lopinavir/ritonavir.

Lopinavir (LPV)/ritonavir (RTV) used in combination, is a potent antiretroviral drug. However, its benefit is limited by its inherent effect on lipid metabolism, causing dislypemia in a large proportion of treated patients. Fasting triglyceride (TG) and cholesterol levels were assessed in 126 HIV-infected patients who initiated salvage therapy based on LPV/RTV.

Gynecomastia in HIV-infected patients receiving antiretroviral therapy.

Thirty-four HIV-positive men with gynecomastia were seen in an HIV outclinic during a 20-month period (incidence of 2.4 cases/100 patients receiving HAART per year). It developed mainly in subjects having good immunologic and virologic status, after an average of 3 years of HAART.

[Mitochondrial damage by antiretrovirals: diagnosis and monitoring].

Combination of antiretroviral drugs has dramatically improved the prognosis of individuals with HIV infection. However, their long-term benefit is limited by two main factors: the selection of drug-resistant strains and side effects. A large part of the toxicity of antiretroviral drugs has been associated with mitochondrial damage.