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Changes in lung function after working with the shotcrete lining method under compressed air conditions.

Kessel, R; Redl, M; Mauermayer, R; Praml, G J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /02/1989 Português
Relevância na Pesquisa
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Shotcrete techniques under compressed air are increasingly applied in the construction of tunnels. Up to now little is known about the influence of shotcrete dusts on the function of the lung. The lung function of 30 miners working with shotcrete under compressed air (before and after one shift) was measured. They carried personal air samplers to assess the total dust exposure. Long term effects were studied on a second group of 29 individuals exposed to shotcrete dusts and compressed air for two years. A significant increase of airway resistance and a significant decrease of some flow-volume parameters were found after one workshift. These changes partially correlate close to the dust exposure. After two years exposure a significant decrease of mean expiratory flow (MEF)50 and MEF25 was found. These results point to damage in the small airways and emphasise the major role of the lung function test--including the flow-volume manoeuvre for the medical examination of the workers. Additionally, they should carry filter masks.

Bronchial symptoms and respiratory function in workers exposed to methylmethacrylate.

Marez, T; Edmé, J L; Boulenguez, C; Shirali, P; Haguenoer, J M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1993 Português
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This study aimed to investigate the pulmonary effects of methylmethacrylate (MMA) in a group of occupationally exposed workers. In the exposed group 20% had chronic cough compared with 1% in controls. Spirometric values at the beginning of the workshift were similar in both groups, but a mild airways obstruction appeared during the workshift. The maximum expiratory flow when 50% of the forced vital capacity remained to be exhaled (MEF50) and the ratio of MEF50 to maximal expiratory flow (MEF50/MEF) decreased significantly during the workshift among exposed workers v controls (p = 0.04 and 0.01 respectively). Results remained unaffected after adjustment for smoking. Exposure to MMA seems to be responsible for a mild airways obstruction but further study on a larger population would be useful.

Genetic Basis of Antibiotic Resistance in Clinical Isolates of Streptococcus gallolyticus (Streptococcus bovis)

Leclercq, Roland; Huet, Corinne; Picherot, Mélanie; Trieu-Cuot, Patrick; Poyart, Claire
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /04/2005 Português
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Among 128 Streptococcus gallolyticus (Streptococcus bovis) isolates, 77.7% were resistant to tetracyclines and contained tet(M) and/or tet(L) and/or tet(O). A total of 59.4% had macrolide resistance and contained erm(B) and, rarely, mef(A). Among the one-third of isolates highly resistant to kanamycin and streptomycin, most harbored aphA3 and aad-6 genes.

Molecular Epidemiology of Macrolide-Resistant Streptococcus pneumoniae Isolates in Europe

Reinert, Ralf René; Ringelstein, Adrian; van der Linden, Mark; Cil, Murat Yücel; Al-Lahham, Adnan; Schmitz, Franz-Josef
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /03/2005 Português
Relevância na Pesquisa
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In many European countries, the level of pneumococcal resistance to macrolides has now passed the level of resistance to penicillin G. A total of 82 erythromycin A-resistant isolates of Streptococcus pneumoniae were collected by 11 laboratories in seven European countries. All of the isolates were tested for antimicrobial susceptibility, analyzed for clonal relatedness by multilocus sequence typing, and characterized for macrolide resistance genotypes. The prevalence of the macrolide resistance genotypes varied substantially between countries. In France (87.5% of all strains), Spain (77.3%), Switzerland (80%), and Poland (100%), strains were predominantly erm(B) positive, whereas higher levels of mef(A)-positive strains were reported from Greece (100%) and Germany (33.3%). Macrolide resistance was caused by the oligoclonal spread of some multilocus sequence types, but significant differences in clonal distribution were noted between France and Spain, countries from which high levels of macrolide resistance have been reported. Overall, sequence type 81 (Spain23F-1 clone) was by far the most widespread. The mainly erm(B)-positive serotype 14 clone (sequence type 143), first reported in Poland in the mid-1990s, is now widespread in France.

Inactivation of CtIP Leads to Early Embryonic Lethality Mediated by G1 Restraint and to Tumorigenesis by Haploid Insufficiency

Chen, Phang-Lang; Liu, Feng; Cai, Suna; Lin, Xiaoqin; Li, Aihua; Chen, Yumay; Gu, Bingnan; Lee, Eva Y.-H. P.; Lee, Wen-Hwa
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /05/2005 Português
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CtIP interacts with a group of tumor suppressor proteins including RB (retinoblastoma protein), BRCA1, Ikaros, and CtBP, which regulate cell cycle progression through transcriptional repression as well as chromatin remodeling. However, how CtIP exerts its biological function in cell cycle progression remains elusive. To address this issue, we generated an inactivated Ctip allele in mice by inserting a neo gene into exon 5. The corresponding Ctip−/− embryos died at embryonic day 4.0 (E4.0), and the blastocysts failed to enter S phase but accumulated in G1, leading to a slightly elevated cell death. Mouse NIH 3T3 cells depleted of Ctip were arrested at G1 with the concomitant increase in hypophosphorylated Rb and Cdk inhibitors, p21. However, depletion of Ctip failed to arrest Rb−/− mouse embryonic fibroblasts (MEF) or human osteosarcoma Saos-2 cells at G1, suggesting that this arrest is RB dependent. Importantly, the life span of Ctip+/− heterozygotes was shortened by the development of multiple types of tumors, predominantly, large lymphomas. The wild-type Ctip allele and protein remained detectable in these tumors, suggesting that haploid insufficiency of Ctip leads to tumorigenesis. Taken together, this finding uncovers a novel G1/S regulation in that CtIP counteracts Rb-mediated G1 restraint. Deregulation of this function leads to a defect in early embryogenesis and contributes...

Combined Antimicrobial Resistance in Enterococcus faecium Isolated from Chickens

Petsaris, Odile; Miszczak, Fabien; Gicquel-Bruneau, Mireille; Perrin-Guyomard, Agnès; Humbert, Florence; Sanders, Pascal; Leclercq, Roland
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /05/2005 Português
Relevância na Pesquisa
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Nineteen E. faecium strains isolated from chicken caecum samples, collected in slaughterhouses and highly resistant to vancomycin or gentamicin, were coresistant to erythromycin, and/or tetracyclines, and/or streptogramins, and/or avilamycin. Multiple antibiotic resistance was related to the presence in various combinations of aac(6′)-aph(2"), erm(B), emtA, mef(A), tet(L), tet(M), and vanA genes.

Dust exposure, respiratory symptoms, and longitudinal decline of lung function in young coal miners.

Carta, P; Aru, G; Barbieri, M T; Avataneo, G; Casula, D
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /05/1996 Português
Relevância na Pesquisa
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OBJECTIVES: To study the role of dust exposure on incidence of respiratory symptoms and decline of lung function in young coal miners. METHODS: The loss of lung function (forced vital capacity (FVC), forced expiratory volume in one second (FEV1), forced expiratory flow (MEF), carbon monoxide transfer factor (TLCO)) with time and the incidence of respiratory symptoms in 909 Sardinian coal miners (followed up between 1983 and 1993 with seven separate surveys) has been compared with the past and current individual exposures to respirable mixed coal dust. Multiple linear and logistic regression models were used simultaneously controlling for age, smoking, past occupational exposures, and other relevant covariates. RESULTS: According to the relatively low dust exposures experienced during the follow up few abnormal chest x ray films were detected. In the cross sectional analysis of initial data, significant associations between individual cumulative exposure to dust, decrements in FEV1 and MEFs, and increasing prevalence of respiratory symptoms were detected after allowing for the covariates included in the model. The yearly decline of FVC, FEV1, and single breath carbon monoxide transfer factor (TLCO/VA) was still significantly related to the individual exposure to dust experienced during the follow up...

Multicenter Study of the Mechanisms of Resistance and Clonal Relationships of Streptococcus agalactiae Isolates Resistant to Macrolides, Lincosamides, and Ketolides in Spain

Gonzalez, J. J.; Andreu, A.;
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /06/2005 Português
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Macrolide, lincosamide, and ketolide mechanisms of resistance and clonal relationships were characterized in a collection of 79 resistant group B streptococcus isolates obtained from neonates or pregnant women. The erm(B), erm(TR), and mef(A) genes were present in 62%, 30.4%, and 3.8% of the isolates, respectively. There was considerable clonal diversity among them.

Decreased Growth of Vhl−/− Fibrosarcomas Is Associated with Elevated Levels of Cyclin Kinase Inhibitors p21 and p27

Mack, Fiona A.; Patel, Jagruti H.; Biju, Mangatt P.; Haase, Volker H.; Simon, M. Celeste
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /06/2005 Português
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Inactivating mutations within the von Hippel-Lindau (VHL) tumor suppressor gene predispose patients to develop a variety of highly vascularized tumors. pVHL targets α subunits of the heterodimeric transcription factor hypoxia-inducible factor (HIF), a critical regulator of energy metabolism, angiogenesis, hematopoiesis, and oxygen (O2) delivery, for ubiquitin-mediated degradation in an O2-dependent manner. To investigate the role of Vhl in cellular proliferation and tumorigenesis, we utilized mouse embryonic fibroblasts (MEFs), a common tool for analyzing cell cycle regulation, and generated Vhl−/− MEF-derived fibrosarcomas. Surprisingly, growth of both Vhl−/− MEFs and fibrosarcomas was impaired, although tumor vascularity was increased. Decreased proliferation of Vhl−/− MEFs was correlated with an overexpression of cyclin kinase inhibitors (CKIs) p21 and p27. The transcription of p21 and p27 is inhibited by c-Myc; therefore, the induction of CKIs was attributed to the ability of HIF to antagonize c-Myc activity. Indeed, p21 mRNA levels were elevated under normoxia in Vhl−/− MEFs, while c-Myc transcriptional activity was markedly reduced. Gene silencing of HIF-1α by small interfering RNA reduced p21 and p27 protein and mRNA levels in Vhl−/− MEFs. The induction of p21 and p27...

Predominance of 23S rRNA Mutants among Non-Erm, Non-Mef Macrolide-Resistant Clinical Isolates of Streptococcus pneumoniae Collected in the United States in 1999-2000

Davies, Todd A.; Bush, Karen; Sahm, Daniel; Evangelista, Alan
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /07/2005 Português
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A total of 322 erythromycin-resistant pneumococci from TRUST 3 and TRUST 4 United States surveillance studies (1999-2000) were screened for 23S rRNA, L4, and L22 gene mutations. Nineteen isolates, two with mefA, had mutations at position 2058 or 2059 in 23S rRNA. Two had a 69GTG71-to-TPS substitution in L4; one of these also contained ermA.

Antimicrobial Susceptibility of Streptococcus pneumoniae in Eight European Countries from 2001 to 2003

Reinert, Ralf René; Reinert, Susanne; van der Linden, Mark; Cil, Murat Y.; Al-Lahham, Adnan; Appelbaum, Peter
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /07/2005 Português
Relevância na Pesquisa
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Susceptibility testing results for Streptococcus pneumoniae isolates (n = 2,279) from eight European countries, examined in the PneumoWorld Study from 2001 to 2003, are presented. Overall, 24.6% of S. pneumoniae isolates were nonsusceptible to penicillin G and 28.0% were resistant to macrolides. The prevalence of resistance varied widely between European countries, with the highest rates of penicillin G and macrolide resistance reported from Spain and France. Serotype 14 was the leading serotype among penicillin G- and macrolide-resistant S. pneumoniae isolates. One strain (PW 158) showed a combination of an efflux type of resistance with a 23S rRNA mutation (A2061G, pneumococcal numbering; A2059G, Escherichia coli numbering). Six strains which showed negative results for mef(A) and erm(B) in repeated PCR assays had mutations in 23S rRNA or alterations in the L4 ribosomal protein (two strains). Fluoroquinolone resistance rates (levofloxacin MIC ≥ 4 μg/ml) were low (Austria, 0%; Belgium, 0.7%; France, 0.9%; Germany, 0.4%; Italy, 1.3%; Portugal, 1.2%; Spain, 1.0%; and Switzerland, 0%). Analysis of quinolone resistance-determining regions showed eight strains with a Ser81 alteration in gyrA; 13 of 18 strains showed a Ser79 alteration in parC. The clonal profile...

ZEB, a vertebrate homolog of Drosophila Zfh-1, is a negative regulator of muscle differentiation.

Postigo, A A; Dean, D C
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 01/07/1997 Português
Relevância na Pesquisa
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A number of genes, spanning the evolutionary scale from yeast to mammals, that are involved in spatial and temporal patterning during development contain zinc finger and homeodomain motifs. One such zinc finger/homeodomain protein is Drosophila Zfh-1, a member of the zfh family of Drosophila genes, which is expressed in muscle precursors and is critical for the proper development of muscle. Here we demonstrate that a vertebrate homolog of Zfh-1 (ZEB) is a negative regulator of muscle differentiation. We show that ZEB binds to a subset of E boxes in muscle genes and functions by actively repressing transcription. One target of this repression is the members of the MEF-2 family, which synergize with proteins of the myogenic basic helix-loop-helix family (bHLH) (myoD, myf-5, myogenin and MRF-4) to induce myogenic differentiation. As muscle differentiation proceeds, myogenic bHLH proteins accumulate to levels sufficient to displace ZEB from the E boxes, releasing the repression and allowing bHLH proteins to further activate transcription. This mechanism of active transcriptional repression distinguishes ZEB from other negative regulators of myogenesis (Id, Twist and I-mfa) that inhibit muscle differentiation by simply binding and inactivating myogenic factors. The relative affinity of ZEB versus myogenic bHLH proteins varies for E boxes in different genes such that ZEB would be displaced from different genes at distinct times as myogenic bHLH proteins accumulate during myogenesis...

Multiplex PCR for Simultaneous Detection of Macrolide and Tetracycline Resistance Determinants in Streptococci

Malhotra-Kumar, Surbhi; Lammens, Christine; Piessens, Jasper; Goossens, Herman
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /11/2005 Português
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Resistance to macrolides and tetracyclines is increasing among streptococci and co-occurs as their resistance determinants are carried on the same mobile element. We developed a multiplex PCR to facilitate simultaneous and specific detection of resistance determinants for both macrolides [erm(A), erm(B), and mef(A/E)] and tetracyclines [tet(M), tet(O), tet(K), and tet(L)] in streptococci.

Comparison of the cardiovascular and pulmonary effects of oral celiprolol, propranolol and placebo in normal volunteers.

Busst, C M; Bush, A
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /04/1989 Português
Relevância na Pesquisa
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1. The effects on heart rate, blood pressure and pulmonary function of single oral doses of celiprolol hydrochloride (400 mg), and propranolol (40 mg) were compared with placebo in 12 healthy volunteers, in a double-blind three-period crossover study. 2. Celiprolol had no effect on heart rate while propranolol caused a significant reduction compared with placebo. Systolic blood pressure was reduced by propranolol but not celiprolol, whereas standing diastolic blood pressure was lowered by both drugs. 3. The maximal expiratory flow at 50% vital capacity (MEF.50), was significantly lower after propranolol compared with placebo and celiprolol. Celiprolol had no effect on the flow-volume loop parameters. 4. Effective pulmonary blood flow was significantly increased by celiprolol, but reduced by propranolol. 5. A high incidence of subjective side-effects were experienced on celiprolol (10/12; particularly unpleasant in 5). Side-effects were experienced to a lesser extent on placebo (8/12). Only one volunteer experienced a side-effect on propranolol. 6. Oral celiprolol exerts its hypotensive effect by vasodilatation without reflex tachycardia. It does not cause airways obstruction in healthy subjects.

CHEK2 1100delC in patients with metachronous cancers of the breast and the colorectum

Isinger, Anna; Bhat, Misha; Borg, Ake; Nilbert, Mef
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
Publicado em 15/03/2006 Português
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140.000625%

Pulmonary effects in man of oral prizidilol hydrochloride (SK&F 92657), a new antihypertensive agent.

Edmondstone, W M; Waller, J F; Manghani, K K; Hill, P L; Bell, A J; Denison, D M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /12/1983 Português
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The effects on heart rate, blood pressure and pulmonary function of single oral doses of prizidilol hydrochloride (400 mg SK&F 92657) and propranolol (40 mg) were compared with placebo in nine healthy volunteers, in a double blind crossover study. Prizidilol had no effect on heart rate while propranolol caused a significant reduction compared with placebo. Diastolic blood pressure was lowered to the same extent by both prizidilol and propranolol. Propranolol significantly reduced the forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC) and the maximal expiratory flow at 50% vital capacity (MEF 50). Prizidilol had no effect on flow-volume loop parameters. Effective pulmonary blood flow was not altered by propranolol, but it was significantly increased by prizidilol. Oral prizidilol exerts its hypotensive effect by vasodilatation without reflex tachycardia. It does not cause airways obstruction in healthy subjects.

The Molecular Scaffold Kinase Suppressor of Ras 1 Is a Modifier of RasV12-Induced and Replicative Senescence

Kortum, Robert L.; Johnson, Heidi J.; Costanzo, Diane L.; Volle, Deanna J.; Razidlo, Gina L.; Fusello, Angela M.; Shaw, Andrey S.; Lewis, Robert E.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /03/2006 Português
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In primary mouse embryo fibroblasts (MEFs), oncogenic Ras induces growth arrest via Raf/MEK/extracellular signal-regulated kinase (ERK)-mediated activation of the p19ARF/p53 and INK4/Rb tumor suppressor pathways. Ablation of these same pathways causes spontaneous immortalization in MEFs, and oncogenic transformation by Ras requires ablation of one or both of these pathways. We show that Kinase Suppressor of Ras 1 (KSR1), a molecular scaffold for the Raf/MEK/ERK cascade, is necessary for RasV12-induced senescence, and its disruption enhances primary MEF immortalization. RasV12 failed to induce p53, p19ARF, p16INK4a, and p15INK4b expression in KSR1−/− MEFs and increased proliferation instead of causing growth arrest. Reintroduction of wild-type KSR1, but not a mutated KSR1 construct unable to bind activated ERK, rescued RasV12-induced senescence. On continuous culture, deletion of KSR1 accelerated the establishment of spontaneously immortalized cultures and increased the proportion of cultures escaping replicative crisis. Despite enhancing escape from both RasV12-induced and replicative senescence, however, both primary and immortalized KSR1−/− MEFs are completely resistant to RasV12-induced transformation. These data show that escape from senescence is not necessarily a precursor for oncogenic transformation. Furthermore...

Uncleaved TFIIA Is a Substrate for Taspase 1 and Active in Transcription

Zhou, Huiqing; Spicuglia, Salvatore; Hsieh, James J.-D.; Mitsiou, Dimitra J.; Høiby, Torill; Veenstra, Gert Jan C.; Korsmeyer, Stanley J.; Stunnenberg, Hendrik G.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /04/2006 Português
Relevância na Pesquisa
140.000625%
In higher eukaryotes, the large subunit of the general transcription factor TFIIA is encoded by the single TFIIAαβ gene and posttranslationally cleaved into α and β subunits. The molecular mechanisms and biological significance of this proteolytic process have remained obscure. Here, we show that TFIIA is a substrate of taspase 1 as reported for the trithorax group mixed-lineage leukemia protein. We demonstrate that recombinant taspase 1 cleaves TFIIA in vitro. Transfected taspase 1 enhances cleavage of TFIIA, and RNA interference knockdown of endogenous taspase 1 diminishes cleavage of TFIIA in vivo. In taspase 1−/− MEF cells, only uncleaved TFIIA is detected. In Xenopus laevis embryos, knockdown of TFIIA results in phenotype and expression defects. Both defects can be rescued by expression of an uncleavable TFIIA mutant. Our study shows that uncleaved TFIIA is transcriptionally active and that cleavage of TFIIA does not serve to render TFIIA competent for transcription. We propose that cleavage fine tunes the transcription regulation of a subset of genes during differentiation and development.

Drosophila starvin Encodes a Tissue-Specific BAG-Domain Protein Required for Larval Food Uptake

Coulson, Michelle; Robert, Stanley; Saint, Robert
Fonte: Copyright © 2005 by the Genetics Society of America Publicador: Copyright © 2005 by the Genetics Society of America
Tipo: Artigo de Revista Científica
Publicado em /12/2005 Português
Relevância na Pesquisa
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We describe a developmental, genetic, and molecular analysis of the sole Drosophila member of the BAG family of genes, which is implicated in stress response and survival in mammalian cells. We show that the gene, termed starvin (stv), is expressed in a highly tissue-specific manner, accumulating primarily in tendon cells following germ-band retraction and later in somatic muscles and the esophagus during embryonic stage 15. We show that stv expression falls within known tendon and muscle cell transcriptional regulatory cascades, being downstream of stripe, but not of another tendon transcriptional regulator, delilah, and downstream of the muscle regulator, mef-2. We generated a series of stv alleles and, surprisingly, given the muscle and tendon-specific embryonic expression of stv, found that the gross morphology and function of somatic muscles is normal in stv mutants. Nonetheless, stv mutant larvae exhibit a striking and fully penetrant mutant phenotype of failure to grow after hatching and a severely impaired ability to take up food. Our study provides the first report of an essential, developmentally regulated BAG-family gene.

Macrolide-Resistant Streptococcus pyogenes in Norway: Population Structure and Resistance Determinants

Littauer, P.; Caugant, D. A.; Sangvik, M.; Høiby, E. A.; Sundsfjord, A.; Simonsen, G. S.;
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /05/2006 Português
Relevância na Pesquisa
140.000625%
A 2.7% prevalence of macrolide resistance in 1,657 Norwegian clinical Streptococcus pyogenes isolates was primarily due to erm(TR) (59%) and mef(A) (20%). Four clonal complexes comprised 75% of the strains. Macrolide resistance in S. pyogenes in Norway is imported as resistant strains or locally selected in internationally disseminated susceptible clones.