Search results for "Type I"
showing 10 items of 966 documents
Susceptibility to collagen-induced arthritis is modulated by TGFβ responsiveness of T cells
2004
The objective of our study was to determine the regulatory effects that endogenous transforming growth factor beta (TGFbeta) exerts on T cells in the pathogenesis of collagen-induced arthritis (CIA). CIA was induced in transgenic mice expressing a dominant negative TGFbeta type II receptor in T cells under the control of the human CD2 promoter. Clinical and histological arthritis scores were determined and experiments on disease induction and the healing phase of disease were performed. The proliferation and cytokine production of draining lymph node cells in vitro were analyzed. Transgenic mice were more susceptible to induction of CIA. The overall incidence was higher in transgenic mice t…
Alteration of DNA topoisomerase II activity during infection of H9 cells by human immunodeficiency virus type 1 in vitro: a target for potential ther…
1990
Infection of H9 cells with human immunodeficiency virus type 1 (HIV-1) was found to decrease the phosphorylation of DNA topoisomerase II during the initial phase of infection. Simultaneously, with a later overshoot of phosphorylation and the subsequent activation of DNA topoisomerase II, the production of HIV-1 started. Applying three new protein kinase C inhibitors from the class of O-alkylglycerophospholipids we demonstrated that inhibition of protein kinase C-mediated phosphorylation of DNA topoisomerase II resulted in an inhibition of HIV-1 production. Based on the differential effect of the two protein kinase C activators, phorbol ester and bryostatin, we conclude that phosphorylation …
Development of spontaneous airway changes consistent with human asthma in mice lacking T-bet.
2002
Human asthma is associated with airway infiltration by T helper 2 (TH2) lymphocytes. We observed reduced expression of the TH1 transcription factor, T-bet, in T cells from airways of patients with asthma compared with that in T cells from airways of nonasthmatic patients, suggesting that loss of T-bet might be associated with asthma. Mice with a targeted deletion of the T-bet gene and severe combined immunodeficient mice receiving CD4+cells from T-bet knockout mice spontaneously demonstrated multiple physiological and inflammatory features characteristic of asthma. Thus, T-bet deficiency, in the absence of allergen exposure, induces a murine phenotype reminiscent of both acute and chronic h…
CCL5(RANTES) inhibits TGFbeta1 induced collagen production in human bronchial epithelial cells by action of Smad protein
2009
Airway epithelial cells modulate bronchial remodelling in COPD and asthma. TGF-β1 up-regulation was observed in the bronchial epithelial cells of asthmatics and COPD patients. TGF-β is involved in airways remodelling mainly acting via the Smad pathway. Increased CCL5 was also observed in bronchi of patients with severe COPD. We investigated the effects of TGF-β1 on collagen type I, Smad 3-4 and 7 expression and the effects of CCL5 on TGF-β1-induced collagen production in human bronchial epithelial cells (16HBE).Cells were treated with 10ng/ml of TGF-β1, 10ng/ml of CCL5 and 10ng/ml of both TGF-β1 and CCL5 for 0,3 and 24 hours.TGF-b1 increased Smad3,Smad4 and collagen type I(p=0.0472, p=0.043…
Radio Insight into the Nature of Type IIb Progenitors
2011
AbstractWe present the results of over two decades of radio observations of type IIb Supernovae with the Very Large Array and the Australia Telescope Compact Array. These radio studies illustrate the need for multi-wavelength follow-up to determine the progenitor scenario for type IIb events.
Co-regulation between cyclo-oxygenase-2 and inducible nitric oxide synthase expression in the time-course of murine inflammation.
2000
Many in vitro studies have used cell cultures to focus on the relationships between cyclo-oxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) isoforms. We have investigated the time-course of regulation and the role of COX-2 and iNOS in a model of experimental inflammation in mice, the air pouch injected with zymosan. This study demonstrates that there is an early acute phase (4 h) mediated mainly by eicosanoids, with high levels of prostaglandin E2 (PGE2) produced by cyclo-oxygenase-1. In addition, in the later phase (from 12 h) there is a participation of nitric oxide (NO) and PGE2 accompanied by co-induction of both iNOS and COX-2. These enzymes were detected in migrating leuk…
pRb suppresses camptothecin-induced apoptosis in human osteosarcoma Saos-2 cells by inhibiting c-Jun N-terminal kinase
2001
AbstractThis paper studies the cytotoxic effect induced by the topoisomerase I inhibitor camptothecin in human osteosarcoma Saos-2 cells, which lack p53 and contain a non-functional form of the product of the retinoblastoma gene, pRb. Cytotoxicity induced by camptothecin was dose- and time-dependent; the treatment with 100 nM camptothecin reduced cell viability by 50% at 32 h and by 75% at 72 h of exposure. The cytotoxic effect was caused by apoptosis, as ascertained by morphological evidence, acridine orange-ethidium bromide staining and flow cytometric analysis. Apoptosis was accompanied by both the activation of caspase-3 and the fragmentation of poly(ADP-ribose) polymerase. Treatment wi…
Non-cross-linked collagen type I/III materials enhance cell proliferation: in vitro and in vivo evidence
2014
Objective: To analyze Mucograft®(MG), a recently introduced collagen matrix, in vitro and in vivo, and compare it with BioGide®(BG), a well-established collagen membrane, as control. Material and Methods: A detailed analysis of the materials surface and ultra-structure was performed. Cellular growth patterns and proliferation rates of human fibroblasts on MG and BG were analyzed in vitro. In addition, the early tissue reaction of CD-1 mouse to these materials was analyzed by means of histological and histomorphometrical analysis. Results: MG showed a three-fold higher thickness both in dry and wet conditions, when compared to BG. The spongy surface of BG significantly differed from that of …
REDUCTION OF NILUTAMIDE BY NO SYNTHASES : IMPLICATIONS FOR THE ADVERSE EFFECTS OF THIS NITROAROMATIC ANTIANDROGEN DRUG
2003
Nitric oxide synthases (NOSs) are flavohemeproteins that catalyze the oxidation of l-arginine to l-citrulline with formation of the widespread signal molecule NO. Beside their fundamental role in NO biosynthesis, these enzymes are also involved in the formation of reactive oxygen species and in the interactions with some xenobiotic compounds. Nilutamide is a nonsteroidal antiandrogen that behaves as a competitive antagonist of the androgen receptors and is proposed in the treatment of metastatic prostatic carcinoma. However, therapeutic effects of nilutamide are overshadowed by the occurrence of several adverse reactions mediated by toxic mechanism(s), which remain(s) poorly investigated. H…
Prunella vulgaris L. Upregulates eNOS Expression in Human Endothelial Cells
2010
The purported effects of "circulation-improving" herbs used in traditional Chinese medicine (TCM) show striking similarities with the vascular actions of nitric oxide (NO) produced by the endothelial NO synthase (eNOS). We have previously reported that Salviae miltiorrhizae radix and Zizyphi spinosae semen upregulate eNOS expression. In the present study, we studied the effect on eNOS gene expression of 15 Chinese herbs with potential effects on the vasculature, and identified Prunella vulgaris L. (PVL) (flowering spike) as a potent eNOS-upregulating agent. In EA.hy 926 cells, a cell line derived from human umbilical vein endothelial cells (HUVEC), an aqueous extract of PVL increased eNOS …