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51.
Hypomyelination and increased activity of voltage-gated K(+) channels in mice lacking protein tyrosine phosphatase epsilon 下载免费PDF全文
Protein tyrosine phosphatase epsilon (PTP epsilon) is strongly expressed in the nervous system; however, little is known about its physiological role. We report that mice lacking PTP epsilon exhibit hypomyelination of sciatic nerve axons at an early post-natal age. This occurs together with increased activity of delayed- rectifier, voltage-gated potassium (Kv) channels and with hyperphosphorylation of Kv1.5 and Kv2.1 Kv channel alpha-subunits in sciatic nerve tissue and in primary Schwann cells. PTP epsilon markedly reduces Kv1.5 or Kv2.1 current amplitudes in XENOPUS: oocytes. Kv2.1 associates with a substrate-trapping mutant of PTP epsilon, and PTP epsilon profoundly reduces Src- or Fyn-stimulated Kv2.1 currents and tyrosine phosphorylation in transfected HEK 293 cells. In all, PTP epsilon antagonizes activation of Kv channels by tyrosine kinases in vivo, and affects Schwann cell function during a critical period of Schwann cell growth and myelination. 相似文献
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Ákos Boros Ildikó Somogyi Péter Engelmann Andrea Lubics Dóra Reglodi Edit Pollák László Molnár 《Cell and tissue research》2010,339(3):649-653
Pituitary adenylate cyclase activating polypeptide (PACAP)-like molecules have been shown to be present in cocoon albumin
and in Eisenia fetida embryos at an early developmental stage (E1) by immunocytochemistry and radioimmunoassay. Here, we focus on detecting the
stage at which PAC1 receptor (PAC1R)-like immunoreactivity first appears in germinal layers and structures, e.g., various
parts of the central nervous system (CNS), in developing earthworm embryos. PAC1R-like immunoreactivity was revealed by Western
blot and Far Western blot as early as the E2 developmental stage, occurring in the ectoderm and later in specific neurons
of the developing CNS. Labeled CNS neurons were first seen in the supraesophageal ganglion (brain) and subsequently in the
subesophageal and ventral nerve cord ganglia. Ultrastructurally, PAC1Rs were located mainly on plasma membranes and intracellular
membranes, especially on cisternae of the endoplasmic reticulum. Therefore, PACAP-like compounds probably influence the differentiation
of germinal layers (at least the ectoderm) and of some neurons and might act as signaling molecules during earthworm embryonic
development. 相似文献
54.
Edit Kaszab Balázs Kriszt Béla Atzél Gabriella Szabó István Szabó Péter Harkai Sándor Szoboszlay 《Microbial ecology》2010,59(1):37-45
The main aim of this paper was the comprehensive estimation of the occurrence rate and the antibiotic-resistance conditions
of opportunistic pathogen Pseudomonas aeruginosa in hydrocarbon-contaminated environments. From 2002 to 2007, 26 hydrocarbon-contaminated sites of Hungary were screened for
the detection of environmental isolates. Altogether, 156 samples were collected and examined for the determination of appearance, representative cell counts, and
antibiotic-resistance features of P. aeruginosa. The detected levels of minimal inhibitory concentrations of ten different drugs against 36 environmental strains were compared
to the results of a widely used reference strain ATCC 27853 and four other clinical isolates of P. aeruginosa. Based on our long-term experiment, it can be established that species P. aeruginosa was detectable in case of 61.5% of the investigated hydrocarbon-contaminated sites and 35.2% of the examined samples that
shows its widespread occurrence in polluted soil–groundwater systems. In the course of the antibiotic-resistance assay, our
results determined that 11 of the examined 36 environmental strains had multiple drug-resistance against several clinically
effective antimicrobial classes: cephalosporins, wide spectrum penicillins, carbapenems, fluoroquinolones, and aminoglycosides.
The fact that these multiresistant strains were isolated from 8 different hydrocarbon-contaminated sites, mainly from outskirts,
confirms that multiple drug-resistance of P. aeruginosa is widespread not only in clinical, but also in natural surroundings as well. 相似文献
55.
There is still not an appealing and testable model to explain how single-celled organisms, usually following fusion of male
and female gametes, proceed to grow and evolve into multi-cellular, complexly differentiated systems, a particular species
following virtually an invariant and unique growth pattern. An intrinsic electrical oscillator, resembling the cardiac pacemaker,
may explain the process. Highly auto-correlated, it could live independently of ordinary thermodynamic processes which mandate
increasing disorder, and could coordinate growth and differentiation of organ anlage. 相似文献
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Pal Soltesz Daniel Bereczki Peter Szodoray Maria T Magyar Henrietta Der Istvan Csipo Agota Hajas Gyorgy Paragh Gyula Szegedi Edit Bodolay 《Arthritis research & therapy》2010,12(3):R78
Introduction
The aim of the present study was to investigate the association between cardiovascular risk factors and endothelial dysfunction in patients with mixed connective tissue disease (MCTD) and to determine which biomarkers are associated with atherosclerotic complications, such as cardiovascular disease. 相似文献57.
Biochemical assay-based selectivity profiling of clinically relevant kinase inhibitors on mutant forms of EGF receptor 总被引:1,自引:0,他引:1
Varkondi E Pinter F Robert K Schwab R Breza N Orfi L Keri G Petak I 《Journal of receptor and signal transduction research》2008,28(3):295-306
Gefitinib and erlotinib are potent EGFR tyrosine kinase inhibitors (potentially) useful for the treatment of non-small-cell lung cancer (NSCLC). Clinical responses, however, in NSCLC patients have been linked to the presence of certain activating mutations of EGFR. We used an ELISA-based biochemical assay to confirm the selective inhibitory efficacy of gefitinib and erlotinib on the activated mutant receptor. Our results are in line with the clinical observations providing evidence for the predictive power of the kinase assay. Four additional compounds were also investigated: CI-1033 and EKB-569 had dramatic inhibitory effects on all EGFR forms, whereas PD153035 and AG1478 were active on wild-type and activating mutant protein. In docking simulations with wild-type EGFR, our inhibitory data are in good agreement with the binding scores. These data confirm that anilinoquinazolines are good starting structures for the next generation of selective drugs against mutant EGFR, whereas CI-1033 and EKB-569 may represent advances for patients with both wild-type and anilinoquinazoline-resistant mutant tumors. 相似文献
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We report here a rare case of infection caused by Propionibacterium acnes following trauma surgery: a 36-year-old male, accident victim was admitted to the hospital because of polytrauma. He underwent a long-drawn-out surgical intervention and after a free-muscle transfer using the rectus femoris muscle, signs of inflammation were detected in the affected area. Microbiological examination of the wound revealed the presence of P. acnes as the only etiological agent of this infection. Adequate antibiotic treatment with penicillin had been started right after the positive microbiological result. Our data confirm the pathogenic potential of P. acnes in late post-surgical infections, and suggest a proper therapeutic approach with intravenous antibiotics and surgical removal of the infected tissue. 相似文献