995 resultados para Interferon-alpha


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Background: Neutrophil elastase (NE) activity is increased in lung diseases such as a1-antitrypsin (A1AT) deficiency and pneumonia. It has recently been shown to induce expression of cathepsin B and matrix metalloprotease 2 (MMP-2) in vitro and in a mouse model. It is postulated that increased cathepsin B and MMP-2 in acute and chronic lung diseases result from high levels of extracellular NE and that expression of these proteases could be inhibited by A1AT augmentation therapy.

Methods: Cathepsin and MMP activities were assessed in bronchoalveolar lavage (BAL) fluid from patients with A1AT deficiency, pneumonia and control subjects. Macrophages were exposed to BAL fluid rich in free NE from patients with pneumonia following pretreatment with A1AT. MMP-2, cathepsin B, secretory leucoprotease inhibitor (SLPI) and lactoferrin levels were determined in BAL fluid from A1AT-deficient patients before and after aerosolisation of A1AT.

Results: BAL fluid from both patients with pneumonia and those with A1AT deficiency containing free NE had increased cathepsin B and MMP-2 activities compared with BAL fluid from healthy volunteers. The addition of A1AT to BAL fluid from patients with pneumonia greatly reduced NE-induced cathepsin B and MMP-2 expression in macrophages in vitro. A1AT augmentation therapy to A1AT-deficient individuals also reduced cathepsin B and MMP-2 activity in BAL fluid in vivo. Furthermore, A1AT-deficient patients had higher levels of SLPI and lactoferrin after A1AT augmentation therapy.

Conclusion: These findings suggest a novel role for A1AT inhibition of NE-induced upregulation of MMP and cathepsin expression both in vitro and in vivo.

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Proton nuclear magnetic relaxation dispersion (NMRD) profiles were recorded between 0.24 mT and 1.4 T for lanthanum(III)- and gadolinium(III)-containing [15]metallacrown-5 complexes derived from alpha-aminohydroxamic acids and with copper(n) as the ring metal. The influence of the different R-groups on the proton relaxivity was investigated, and a linear relationship between the relaxivity and the molecular mass of the metallacrown complex was found. The selectivity of the metallacrown complexes was tested by transmetalation experiments with zinc(n) ions. The crystal structure of the copper [15]metallacrown-5 gadolinium complex with glycine hydroximate ligands is reported.

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The cis-dihydrodiol metabolite from methyl benzoate has been used as a synthetic precursor of carba-beta-L-galactopyranose, carba-beta-L-talopyranose and carba-alpha-L-talopyranose. The structures and absolute configurations of these carbasugars were determined by a combination of NMR spectroscopy, stereochemical correlation and X-ray crystallography.

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α1-antitrypsin (α1-AT) deficiency is a genetic disease which manifests as early-onset emphysema or liver disease. Although the majority of α1-AT is produced by the liver, it is also produced by bronchial epithelial cells, amongst others, in the lung. Herein, we investigate the effects of mutant Z α1-AT (ZAAT) expression on apoptosis in a human bronchial epithelial cell line (16HBE14o-) and delineate the mechanisms involved.

Control, M variant α1-AT (MAAT)- or ZAAT-expressing cells were assessed for apoptosis, caspase-3 activity, cell viability, phosphorylation of Bad, nuclear factor (NF)-κB activation and induced expression of a selection of pro- and anti-apoptotic genes.

Expression of ZAAT in 16HBE14o- cells, like MAAT, inhibited basal and agonist-induced apoptosis. ZAAT expression also inhibited caspase-3 activity by 57% compared with control cells (p = 0.05) and was a more potent inhibitor than MAAT. Whilst ZAAT had no effect on the activity of Bad, its expression activated NF-κB-dependent gene expression above control or MAAT-expressing cells. In 16HBE14o- cells but not HEK293 cells, ZAAT upregulated expression of cIAP-1, an upstream regulator of NF-κB. cIAP1 expression was increased in ZAAT versus MAAT bronchial biopsies.

The data suggest a novel mechanism by which ZAAT may promote human bronchial epithelial cell survival.

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The implication of radiation-induced bystander effect (RIBE) for both radiation protection and radiotherapy has attracted significant attention, but a key question is how to modulate the RIBE. The present study found that, when a fraction of glioblastoma cells in T98G population were individually targeted with precise helium particles through their nucleus, micronucleus (MN) were induced and its yield increased non-linearly with radiation dose. After co-culturing with irradiated cells, additional MN could be induced in the non-irradiated bystander cells and its yield was independent of irradiation dose, giving direct evidence of a RIBE. Further results showed that the RIBE could be eliminated by pifithrin-alpha (p53 inhibitor) but enhanced by wortmannin (PI3K inhibitor). Moreover, it was found that nitric oxide (NO) contributed to this RIBE, and the levels of NO of both irradiated cells and bystander cells could be extensively diminished by pifithrin-alpha but insignificantly reduced by wortmannin. Our results indicate that RIBE can be modulated by p53 and PI3K through a NO-dependent and NO-independent pathway, respectively. (C) 2009 Elsevier B.V. All rights reserved.

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Rhizopus delemar lipase catalyzed ester hydrolysis of the alpha-methoxy-beta-phenylpropanoate (I) affords the (R)-(+) and (S)-(-) isomers in > 84% enantiomeric excess. Abs. stereochem. was detd. by a single crystal X-ray anal. of a related synthetic analog. The activity of these two enantiomers on glucose transport in vitro and as anti-diabetic agents in vivo is reported and their unexpected equivalence attributed to an enzyme-mediated stereospecific isomerization of the (R)-(+) isomer. Binding studies using recombinant human PPAR-gamma (peroxisomal proliferator activated receptor gamma), now established as a mol. target for this compd. class, indicate a 20-fold higher binding affinity for the (S) antipode relative to the (R) antipode.

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Buckle, D. R.; Cantello, B. C. C.; Cawthorne, M. A.; Coyle, P. J.; Dean, D. K.; Faller, A.; Haigh, D.; Hindley, R. M.; Lefcott, L. J.; et al. Dep. Medicinal Chem., Smithkline Beecham Pharmaceuticals, Surrey, UK. Bioorganic & Medicinal Chemistry Letters (1996), 6(17), 2127-2130. Publisher: Elsevier, CODEN: BMCLE8 ISSN: 0960-894X. Journal written in English. CAN 125:238227 AN 1996:573179 CAPLUS (Copyright (C) 2009 ACS on SciFinder (R)) Abstract The thiazolidine-2,4-dione ring of insulin-sensitizing antidiabetic agents can be replaced by ?-acyl-, ?-alkyl- and ?-(aralkyl)-carboxylic acids. The inclusion of an addnl. lipophilic moiety affords compds., equipotent to BRL 48482.

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A review with 22 refs. The 5-benzylthiazolidine-2,4-dione moiety of insulin sensitizing antidiabetic agents can be replaced by a range of ?-heteroatom functionalized ?-phenylpropanoic acids. ?-Oxy-carboxylic acids show potent antidiabetic activity and one compd., the ?-ethoxyacid (SB 213068), is one of the most potent antihyperglycemic agents yet reported.

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Osteopontin is a secreted, integrin-binding and phosphorylated acidic glycoprotein, which has an important role in tumour progression. We have shown that Wnt, Ets, AP-1, c-jun and beta-catenin/Lef-1/Tcf-1 stimulates OPN transcription in rat mammary carcinoma cells by binding to a specific promoter sequence. However, co-repressors of OPN have not been identified. In this study, we have used the bacterial two-hybrid system to isolate cDNA-encoding proteins that bind to OPN and modulate its role in malignant transformation. Using this approach we isolated interferon-induced transmembrane protein 3 gene (IFITM3) as a potential protein partner. We show that IFITM3 and OPN interact in vitro and in vivo and that IFITM3 reduces osteopontin (OPN) mRNA expression, possibly by affecting OPN mRNA stability. Stable transfection of IFITM3 inhibits OPN, which mediates anchorage-independent growth, cell adhesion and cell invasion. Northern blot analysis revealed an inverse mRNA expression pattern of IFITM3 and OPN in human mammary cell lines. Inhibition of IFITM3 by antisense RNA promoted OPN protein expression, enhanced cell invasion by parental benign non-invasive Rama 37 cells, indicating that the two proteins interact functionally as well. We also identified an IFITM3 DNA-binding domain, which interacts with OPN, deletion of which abolished its inhibitive effect on OPN. This work has shown for the first time that IFITM3 physically interacts with OPN and reduces OPN mRNA expression, which mediates cell adhesion, cell invasion, colony formation in soft agar and metastasis in a rat model system. Oncogene (2010) 29, 752-762; doi: 10.1038/onc.2009.379; published online 9 November 2009