Search results for "proteinas"
showing 10 items of 416 documents
Increase in transmitted resistance to non-nucleoside reverse transcriptase inhibitors among newly diagnosed HIV-1 infections in Europe
2014
Background: One out of ten newly diagnosed patients in Europe was infected with a virus carrying a drug resistant mutation. We analysed the patterns over time for transmitted drug resistance mutations (TDRM) using data from the European Spread program.Methods: Clinical, epidemiological and virological data from 4317 patients newly diagnosed with HIV-1 infection between 2002 and 2007 were analysed. Patients were enrolled using a pre-defined sampling strategy.Results: The overall prevalence of TDRM in this period was 8.9% (95% CI: 8.1-9.8). Interestingly, significant changes over time in TDRM caused by the different drug classes were found. Whereas nucleoside resistance mutations remained con…
ALLOPURINOL BLOCKS AORTIC ANEURYSM IN A MOUSE MODEL OF MARFAN SYNDROME VIA REDUCING AORTIC OXIDATIVE STRESS
2022
ABSTRACTBackgroundIncreasing evidence indicates that redox stress participates in MFS aortopathy, though its mechanistic contribution is little known. We reported elevated reactive oxygen species (ROS) formation and NADPH oxidase NOX4 upregulation in MFS patients and mouse aortae. Here we address the contribution of xanthine oxidoreductase (XOR), which catabolizes purines into uric acid and ROS in MFS aortopathy.Methods and ResultsIn aortic samples from MFS patients, XOR protein expression, revealed by immunohistochemistry, increased in both the tunicae intima and media of the dilated zone. In MFS mice (Fbn1C1041G/+), aortic XOR mRNA transcripts and enzymatic activity of the oxidase form (X…
Metalloproteases meprin α and meprin β are C- and N-procollagen proteinases important for collagen assembly and tensile strength.
2013
Type I fibrillar collagen is the most abundant protein in the human body, crucial for the formation and strength of bones, skin, and tendon. Proteolytic enzymes are essential for initiation of the assembly of collagen fibrils by cleaving off the propeptides. We report that Mep1a −/− and Mep1b −/− mice revealed lower amounts of mature collagen I compared with WT mice and exhibited significantly reduced collagen deposition in skin, along with markedly decreased tissue tensile strength. While exploring the mechanism of this phenotype, we found that cleavage of full-length human procollagen I heterotrimers by either meprin α or meprin β led to the generation of mature collagen molecules that s…
Pharmacologic therapies in endometriosis: a systematic review
2012
To assess the literature on preclinical and clinical efficacy and safety data of pharmacologic groups proposed in the treatment of endometriosis, we performed a systematic review of publications from March 2002 to January 2012 via PubMed search. Additional relevant articles were identified from citations within these publications. A high number of medications were tested in preclinical models of endometriosis due to their theoretic capacity of disrupting important pathophysiologic pathways of the disease, such as inflammatory response, angiogenesis and cell survival, proliferation, migration, adhesion, and invasion. Tumor necrosis factor α-blockers, nuclear factor κB inhibitors, antiangioge…
[Coronary artery ectasia: etiopathogenesis, diagnosis and treatment].
2014
Coronary ectasia is a dilation of coronary arteries, angiographically defined if the diameter of the artery is ≥ 1.5 times greater than that of the intact adjacent vascular segment. An association has been found between coronary artery ectasia and a broad spectrum of different diseases, first of all atherosclerotic coronary artery disease. The mechanisms that determine the abnormal dilatation of the vascular lumen and the etiology of coronary artery ectasia are still poorly understood. Various hypotheses have been formulated over the time, the most accredited between these recognizes as main responsible an uncontrolled activity of a particular family of enzymes that degrade the extracellula…
Autophagy Induces Expression of IL-6 in Human Periodontal Ligament Fibroblasts Under Mechanical Load and Overload and Effects Osteoclastogenesis in v…
2021
Frontiers in physiology 12, 716441 (2021). doi:10.3389/fphys.2021.716441 special issue: "Alveolar Bone: a Pivotal Role in Periodontal Disease Pathobiology and Treatment, Volume I / Fani Anagnostou, Beatriz Castaneda, Frédéric Lézot and Petros Papagerakis"
Proenzyme Structure and Activation of Astacin Metallopeptidase
2010
Proteolysis is regulated by inactive (latent) zymogens, with a prosegment preventing access of substrates to the active-site cleft of the enzyme. How latency is maintained often depends on the catalytic mechanism of the protease. For example, in several families of the metzincin metallopeptidases, a >cysteine switch> mechanism involves a conserved prosegment motif with a cysteine residue that coordinates the catalytic zinc ion. Another family of metzincins, the astacins, do not possess a cysteine switch, so latency is maintained by other means. We have solved the high resolution crystal structure of proastacin from the European crayfish, Astacus astacus. Its prosegment is the shortest struc…
Upregulation of the α-secretase ADAM10 - risk or reason for hope?
2010
A decade ago, a disintegrin and metalloproteinase 10 (ADAM10) was identified as an alpha-secretase and as a key proteinase in the processing of the amyloid precursor protein. Accordingly, the important role that it plays in Alzheimer's disease was manifested. Animal models with an overexpression of ADAM10 revealed a beneficial profile of the metalloproteinase with respect to learning and memory, plaque load and synaptogenesis. Therefore, ADAM10 presents a worthwhile target with respect to the treatment of a neurodegenerative disease such as Morbus Alzheimer. Initially, ADAM10 was suggested to be an enzyme, shaping the extracellular matrix by cleavage of collagen type IV, or to be a tumour n…
MT5-MMP regulates adult neural stem cell functional quiescence through the cleavage of N-cadherin.
2014
The identification of mechanisms that maintain stem cell niche architecture and homeostasis is fundamental to our understanding of tissue renewal and repair. Cell adhesion is a well-characterized mechanism for developmental morphogenetic processes, but its contribution to the dynamic regulation of adult mammalian stem cell niches is still poorly defined. We show that N-cadherin-mediated anchorage of neural stem cells (NSCs) to ependymocytes in the adult murine subependymal zone modulates their quiescence. We further identify MT5-MMP as a membrane-type metalloproteinase responsible for the shedding of the N-cadherin ectodomain in this niche. MT5-MMP is co-expressed with N-cadherin in adult N…