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91.
Pelaia G Gallelli L D'Agostino B Vatrella A Cuda G Fratto D Renda T Galderisi U Piegari E Crimi N Rossi F Caputi M Costanzo FS Vancheri C Maselli R Marsico SA 《Journal of cellular physiology》2007,210(2):489-497
Transforming growth factor-beta1 (TGF-beta1) is crucially involved in the fibrotic events characterizing interstitial lung diseases (ILDs), as well as in the airway remodeling process typical of asthma. Within such a context, the aim of our study was to investigate, in primary cultures of normal and fibrotic human lung fibroblasts (HLFs), the effects of TGF-beta1 on mitogen-activated protein kinase (MAPK) phosphorylation, cell proliferation, and production of interleukins 6 (IL-6) and 11 (IL-11), in the presence or absence of a pretreatment with budesonide (BUD). MAPK phosphorylation was detected by Western blotting, cell viability and proliferation were evaluated using Trypan blue staining and [(3)H]-thymidine incorporation assay, respectively, and the release of IL-6 and IL-11 into cell culture supernatants was assessed by ELISA. TGF-beta1 (10 ng/ml) significantly stimulated MAPK phosphorylation (P < 0.01), and also enhanced cell proliferation as well as the secretion of both IL-6 and IL-11, which reached the highest increases at the 72nd h of cell exposure to this growth factor. All such effects were prevented by BUD (10(-8) M) and, with the exception of IL-6 release, also by a mixture of MAPK inhibitors. Therefore, our findings suggest that the fibrotic action exerted by TGF-beta1 in the lung is mediated at least in part by MAPK activation and by an increased synthesis of the profibrogenic cytokines IL-6 and IL-11; all these effects appear to be prevented by corticosteroids via inhibition of MAPK phosphorylation. 相似文献
92.
Maria Jesús García Rosario Brieva Francisca Rebolledo Vicente Gotor 《Biotechnology letters》1991,13(12):867-870
Summary 2,2,2-Trifluoroethyl -chloro--phenylacetate is succesfully hydrolysed in organic solvent in the presence of aniline andCandida cylindracea orPseudomonas cepacia lipase as catalysts. 相似文献
93.
Ma Rosario de la Torre Angela Casado Ma Encarnación López-Fernández Diana Carrascosa Ma Concepción Casado Domenico Venarucci Vincenzo Venarucci 《Neurochemical research》1996,21(8):885-888
In order to investigate the role of two free radical detoxificant enzymes in patients with aging brain disorders, superoxide
dismutase (SOD) and catalase (CAT) activities have been measured in blood from male and female human patients of different
ages with several types of aging brain disorders. When compared with activities in the normal population, we have detected:
1) SOD and CAT activities are decreased in patients with Parkinson disease. 2) SOD activity seems to be normal and CAT activity
is decreased in patients with dementia. 3) In the patients with stroke, SOD activity is normal, while CAT activity is decreased.
SOD activity was measured in red blood cells using the Minami and Yoshikawa method. CAT activity was measured in hemolysates
by the method of Aebi. We can conclude that SOD and CAT activities in patients with Parkinson disease are decreased. 相似文献
94.
Tom Wingfield Delia Boccia Marco Tovar Arquímedes Gavino Karine Zevallos Rosario Montoya Knut L?nnroth Carlton A. Evans 《PLoS medicine》2014,11(7)
Background
Even when tuberculosis (TB) treatment is free, hidden costs incurred by patients and their households (TB-affected households) may worsen poverty and health. Extreme TB-associated costs have been termed “catastrophic” but are poorly defined. We studied TB-affected households'' hidden costs and their association with adverse TB outcome to create a clinically relevant definition of catastrophic costs.Methods and Findings
From 26 October 2002 to 30 November 2009, TB patients (n = 876, 11% with multi-drug-resistant [MDR] TB) and healthy controls (n = 487) were recruited to a prospective cohort study in shantytowns in Lima, Peru. Patients were interviewed prior to and every 2–4 wk throughout treatment, recording direct (household expenses) and indirect (lost income) TB-related costs. Costs were expressed as a proportion of the household''s annual income. In poorer households, costs were lower but constituted a higher proportion of the household''s annual income: 27% (95% CI = 20%–43%) in the least-poor houses versus 48% (95% CI = 36%–50%) in the poorest. Adverse TB outcome was defined as death, treatment abandonment or treatment failure during therapy, or recurrence within 2 y. 23% (166/725) of patients with a defined treatment outcome had an adverse outcome. Total costs ≥20% of household annual income was defined as catastrophic because this threshold was most strongly associated with adverse TB outcome. Catastrophic costs were incurred by 345 households (39%). Having MDR TB was associated with a higher likelihood of incurring catastrophic costs (54% [95% CI = 43%–61%] versus 38% [95% CI = 34%–41%], p<0.003). Adverse outcome was independently associated with MDR TB (odds ratio [OR] = 8.4 [95% CI = 4.7–15], p<0.001), previous TB (OR = 2.1 [95% CI = 1.3–3.5], p = 0.005), days too unwell to work pre-treatment (OR = 1.01 [95% CI = 1.00–1.01], p = 0.02), and catastrophic costs (OR = 1.7 [95% CI = 1.1–2.6], p = 0.01). The adjusted population attributable fraction of adverse outcomes explained by catastrophic costs was 18% (95% CI = 6.9%–28%), similar to that of MDR TB (20% [95% CI = 14%–25%]). Sensitivity analyses demonstrated that existing catastrophic costs thresholds (≥10% or ≥15% of household annual income) were not associated with adverse outcome in our setting. Study limitations included not measuring certain “dis-saving” variables (including selling household items) and gathering only 6 mo of costs-specific follow-up data for MDR TB patients.Conclusions
Despite free TB care, having TB disease was expensive for impoverished TB patients in Peru. Incurring higher relative costs was associated with adverse TB outcome. The population attributable fraction indicated that catastrophic costs and MDR TB were associated with similar proportions of adverse outcomes. Thus TB is a socioeconomic as well as infectious problem, and TB control interventions should address both the economic and clinical aspects of this disease. Please see later in the article for the Editors'' Summary 相似文献95.
96.
CcaR is an autoregulatory protein that binds to the ccaR and cefD-cmcI promoters of the cephamycin C-clavulanic acid cluster in Streptomyces clavuligerus 下载免费PDF全文
Santamarta I Rodríguez-García A Pérez-Redondo R Martín JF Liras P 《Journal of bacteriology》2002,184(11):3106-3113
The putative regulatory CcaR protein, which is encoded in the beta-lactam supercluster of Streptomyces clavuligerus, has been partially purified by ammonium sulfate precipitation and heparin affinity chromatography. In addition, it was expressed in Escherichia coli, purified as a His-tagged recombinant protein (rCcaR), and used to raise anti-rCcaR antibodies. The partially purified CcaR protein from S. clavuligerus was able to bind DNA fragments containing the promoter regions of the ccaR gene itself and the bidirectional cefD-cmcI promoter region. In contrast, CcaR did not bind to DNA fragments with the promoter regions of other genes of the cephamycin-clavulanic acid supercluster including lat, blp, claR, car-cyp, and the unlinked argR gene. The DNA shifts obtained with CcaR were prevented by anti-rCcaR immunoglobulin G (IgG) antibodies but not by anti-rabbit IgG antibodies. ccaR and the bidirectional cefD-cmcI promoter region were fused to the xylE reporter gene and expressed in Streptomyces lividans and S. clavuligerus. These constructs produced low catechol dioxygenase activity in the absence of CcaR; activity was increased 1.7- to 4.6-fold in cultures expressing CcaR. Amplification of the ccaR promoter region lacking its coding sequence in a high-copy-number plasmid in S. clavuligerus ATCC 27064 resulted in a reduced production of cephamycin C and clavulanic acid, by 12 to 20% and 40 to 60%, respectively, due to titration of the CcaR regulator. These findings confirm that CcaR is a positively acting autoregulatory protein able to bind to its own promoter as well as to the cefD-cmcI bidirectional promoter region. 相似文献
97.
Zuzana Technikova-Dobrova Anna Maria Sardanelli Maurizio Rosario Stanca Sergio Papa 《FEBS letters》1994,350(2-3):187-191
A study is presented of the cAMP-dependent phosphorylation in bovine heart mitochondria of three proteins of 42, 16 and 6.5 kDa associated to the inner membrane. These proteins are also phosphorylated by the cytosolic cAMP-dependent protein kinase and by the purified catalytic subunit of this enzyme. In the cytosol, proteins of 16 and 6.5 kDa are phosphorylated by the cAMP-dependent kinase. It is possible that cytosolic and mitochondrial cAMP-dependent kinases phosphorylate the same proteins in the two compartments. 相似文献
98.
Casado A Encarnación López-Fernández M Concepción Casado M de La Torre R 《Neurochemical research》2008,33(3):450-458
It has been reported that oxidative stress may play a role in the pathogenesis of dementia of the Alzheimer type (AD) and
the cerebral ischemia which causes vascular dementia (VD). We measured malondialdehyde (MDA) levels and superoxide dismutase
(SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) activities in blood samples from patients
with AD and VD and in healthy non-demented controls (CTR) which similar ages to the patients, in order to evaluate the degree
of oxidative stress in patients with AD and VD. A sample of 150 subjects consisting of 50 patients with AD; 50 patients with
VD and 50 CTR, aged from 65 to 85 years on, was analyzed. Most of the changes observed were in SOD activity and MDA levels. Catalase activity were least affected. Significant differences were observed in SOD and GR activity between males and females in CRT and in patients with AD, but
not in VD. We have found a decrease in antioxidant enzymes activities (SOD, CAT, GPx and GR) in patients with AD and VD and
significant differences were observed between CRT and AD patients for ages from 65 to 74, 75 to 84 and from 85 years to 94 years
in SOD activity and MDA levels (P < 0.001). MDA levels increase with age in VD, AD and CTR. No significant variation with respect to sex were detected, but
significant variations in MDA levels were detected between CRT and patients with VD and AD (P < 0.001). We conclude that oxidative stress plays an important role in the brain damage for both AD and VD, being observed
higher levels of oxidative stress for AD that for VD. 相似文献
99.
Bryan D. Bryson Amanda M. Del Rosario Jonathan S. Gootenberg Michael B. Yaffe Forest M. White 《Proteomics》2015,15(9):1470-1475
MS‐based analysis of the acetylproteome has highlighted a role for acetylation in a wide array of biological processes including gene regulation, metabolism, and cellular signaling. To date, anti‐acetyllysine antibodies have been used as the predominant affinity reagent for enrichment of acetyllysine‐containing peptides and proteins; however, these reagents suffer from high nonspecific binding and lot‐to‐lot variability. Bromodomains represent potential affinity reagents for acetylated proteins and peptides, given their natural role in recognition of acetylated sequence motifs in vivo. To evaluate their efficacy, we generated recombinant proteins representing all known yeast bromodomains. Bromodomain specificity for acetylated peptides was determined using degenerate peptide arrays, leading to the observation that different bromodomains display a wide array of binding specificities. Despite their relatively weak affinity, we demonstrate the ability of selected bromodomains to enrich acetylated peptides from a complex biological mixture prior to mass spectrometric analysis. Finally, we demonstrate a method for improving the utility of bromodomain enrichment for MS through engineering novel affinity reagents using combinatorial tandem bromodomain pairs. 相似文献
100.
Citores Luca; de Benito Fernando M.; Iglesias Rosario; Ferreras J. Miguel; Jimnez Pilar; Argeso Pablo; Farias Gustavo; Mndez Enrique; Girbs Toms 《Journal of experimental botany》1996,47(10):1577-1585
Sambucus (Caprifoliaceae) species contain nigrin b and ebulinI, which are two-chain ribosomeinactivating proteins (RIPs)belonging to a new type of RIPS which are non-toxic to miceand cultured human cells. In this work the presence in fruitsof elder (S. nigra L.) of a new non-toxic type 2 RIP (nigrinf) that co-exists with a lectin known as SNA IV is described.Nigrin f strongly inhibited protein synthesis in mammalian,but not in plant, ribosomes, promoting the depurination of sensitiveribosomes and thus allowing the release of the RIP diagnosticRNA fragment. Nigrin f is composed of two dissimilar subunitslinked by disulphide bridges with apparent Mr values of 31 600and 26 300. The N-terminal amino acid sequence revealed closehomology of the catalytic A chain with type 1 RIPs, especiallythose from Cucurbitaceae, and the B chain with several lectinspreviously isolated from Sambucus species. Nigrin f was nottoxic to mice when injected intraperitoneally up to 2 mg kg1.In addition, NHC human cells were also insensitive to nigrinf up to 60 µg ml1. Anti-nigrin b rabbit polyclonalantibodies reacted with nigrin f, indicating that nigrin b andnigrin f are proteins with similar structures. Key words: Sambucus nigra, elder fruits, nigrin f, ribosomeinactivating protein, characterization 相似文献