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1.
Pneumologie ; 70(5): 314-9, 2016 May.
Artigo em Alemão | MEDLINE | ID: mdl-26956576

RESUMO

BACKGROUND: In the process of medical rehabilitation muscular endurance training is the main focus. Unfortunately, outpatient rehabilitation opportunities are limited and specialized pulmonary exercise groups ("lung sport groups") rarely available. Therefore we developed an outpatient endurance sports program for patients with respiratory diseases and evaluated its effectiveness. METHODS: In this feasibility study 31 patients (50 ±â€Š15 years) with diverse respiratory diseases were included. By professional functional exercise testing (incl. CPET and lactate measurement according to the standards of DGP and DGSP) the patients optimal training zone was determined and an individualized 12 week lasting aerobic endurance training with ≥ 3 sessions of 20 - 60 min/week realized. RESULTS: After completion of the exercise training program a significant improvement in dyspnoea (Borg-Scale: 65.7 ±â€Š12.2 vs. 62.2 ±â€Š12.6, p = 0.013), body constitution (BMI: 25.7 ±â€Š3.3 vs. 24.3 ±â€Š3.2 kg/m(2), p = 0.018; portion of body fat: 24.8 ±â€Š5.8 vs. 23.8 ±â€Š6.4 %, p = 0.043) as well as physical capacity (VO2 at 4 mmol/l Laktat: 24.2 ±â€Š6.9 vs. 26.5 ±â€Š7.6 ml/min/kg, p < 0.01; performance at 4 mmol/l Laktat: running/walking (n = 14) + 1.1 km/h, p = 0.018 and biking/bicycle ergometer (n = 17) + 8.7 Watt, p = 0.019) was recorded. These positive developments were also observed in mental and physical quality of life (quality of life questionnaire SF-36: physical score + 9.7 points, mental score + 4.5 points). CONCLUSION: The evaluated exercise program can easily be trained by the patient in a self-dependent setting and was seen to be an effective sports medical treatment in patients with diverse pulmonary diseases.


Assuntos
Assistência Ambulatorial/métodos , Terapia por Exercício/métodos , Treinamento Intervalado de Alta Intensidade/métodos , Resistência Física , Transtornos Respiratórios/reabilitação , Esportes , Estudos de Viabilidade , Feminino , Humanos , Ácido Láctico/sangue , Masculino , Pessoa de Meia-Idade , Condicionamento Físico Humano/métodos , Pneumologia/métodos , Transtornos Respiratórios/sangue , Transtornos Respiratórios/diagnóstico , Testes de Função Respiratória , Autocuidado/métodos , Medicina Esportiva/métodos , Resultado do Tratamento
2.
Amino Acids ; 36(1): 1-11, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18283414

RESUMO

Procedures for the analysis of free alpha-keto acids in human fluids (i.e. plasma, cerebrospinal fluid, urine, etc.) as well as for studying the dynamic free alpha-keto acid pools in differentiated tissues and organ cells have been the subject of growing clinical interest in the study of metabolic regulatory and pathophysiological phenomena. Due to the high instability and polarity of the alpha-keto acids being examined, the development of a quantitative and reproducible analysis of metabolically relevant intracellular alpha-keto acids still presents a substantial methodological challenge. The aim of small sample size, rapid, non-damaging and "metabolism-neutral" cell isolation, careful sample preparation and stability, as well as reproducible analytics technology is not often achieved. Only few of the methods described can satisfy the rigorous demands for an ultra-sensitive, comprehensive and rapid intracellular alpha-keto acid analysis.


Assuntos
Fracionamento Celular/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cetoácidos/análise , Espectrometria de Fluorescência/métodos , Animais , Cromatografia Gasosa , Humanos , Cetoácidos/química , Cetoácidos/metabolismo
3.
Amino Acids ; 34(2): 257-70, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17334904

RESUMO

We examined the effects of beta-alanine (taurine analogue and taurine transport antagonist), taurine (regarding its role in neutrophil (PMN) immunonutrition) and taurine combined either with L-NAME (inhibitor of *NO-synthase), SNAP (*NO donor), DON (glutamine-analogue and inhibitor of glutamine-requiring enzymes), DFMO (inhibitor of ornithine-decarboxylase) and beta-alanine on neutrophil amino- and alpha-keto acid profiles or important PMN immune functions in order to establish whether taurine transport-, nitric oxide-, glutamine- or ornithine-dependent mechanisms are involved in any of the taurine-induced effects. According to the present findings, the taurine-mediated effect appears to be based primarily on a modulation of important transmembraneous transport mechanisms and only secondarily on directly or indirectly induced modifications in intragranulocytic amino- and alpha-keto acid homoeostasis or metabolism. Although a direct relation to the parallel observed immunological modifications can only be presumed, these results show very clearly that compositional modifications in the free intragranulocytic amino- and alpha keto-acid pools coinciding with changes in intragranulocytic taurine levels are relevant metabolic determinants that can significantly influence the magnitude and quality of the granulocytic immune response.


Assuntos
Aminoácidos/metabolismo , Homeostase/efeitos dos fármacos , Cetoácidos/metabolismo , Neutrófilos/fisiologia , Taurina/fisiologia , beta-Alanina/farmacologia , Adulto , Diazo-Oxo-Norleucina/farmacologia , Eflornitina/farmacologia , Humanos , Peróxido de Hidrogênio/metabolismo , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Neutrófilos/imunologia , Peroxidase/metabolismo , S-Nitroso-N-Acetilpenicilamina/farmacologia , Superóxidos/metabolismo
4.
Nucleic Acids Res ; 34(Database issue): D108-10, 2006 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-16381825

RESUMO

The TRANSFAC database on transcription factors, their binding sites, nucleotide distribution matrices and regulated genes as well as the complementing database TRANSCompel on composite elements have been further enhanced on various levels. A new web interface with different search options and integrated versions of Match and Patch provides increased functionality for TRANSFAC. The list of databases which are linked to the common GENE table of TRANSFAC and TRANSCompel has been extended by: Ensembl, UniGene, EntrezGene, HumanPSD and TRANSPRO. Standard gene names from HGNC, MGI and RGD, are included for human, mouse and rat genes, respectively. With the help of InterProScan, Pfam, SMART and PROSITE domains are assigned automatically to the protein sequences of the transcription factors. TRANSCompel contains now, in addition to the COMPEL table, a separate table for detailed information on the experimental EVIDENCE on which the composite elements are based. Finally, for TRANSFAC, in respect of data growth, in particular the gain of Drosophila transcription factor binding sites (by courtesy of the Drosophila DNase I footprint database) and of Arabidopsis factors (by courtesy of DATF, Database of Arabidopsis Transcription Factors) has to be stressed. The here described public releases, TRANSFAC 7.0 and TRANSCompel 7.0, are accessible under http://www.gene-regulation.com/pub/databases.html.


Assuntos
Bases de Dados Genéticas , Regulação da Expressão Gênica , Sequências Reguladoras de Ácido Nucleico , Fatores de Transcrição/metabolismo , Animais , Arabidopsis/genética , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Sítios de Ligação , DNA/química , DNA/metabolismo , Proteínas de Drosophila/química , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Humanos , Internet , Camundongos , Estrutura Terciária de Proteína , Ratos , Integração de Sistemas , Fatores de Transcrição/química , Transcrição Gênica , Interface Usuário-Computador
5.
Allergol Select ; 2(1): 49-55, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31826042

RESUMO

BACKGROUND: Omalizumab is approved as add-on therapy for the treatment of severe uncontrolled allergic asthma. Increase in quality of life and decrease of exacerbations and hospital admission, as well as immunmodulatory effects have been described with omalizumab therapy. However, to date there are few parameters to monitor success and to evaluate the individual advantage of this therapy for the patient. Furthermore, no reliable parameter to predict response to treatment exists so far. The aim of this study was to define an easily applicable parameter for response to treatment with omalizumab. METHOD: 43 patients with allergic asthma were treated with omalizumab at a dose of at least 0,016 mg/kg/IgE every 4 weeks. Before, and 12 weeks after initiation of therapy, bodyplethysmography including airway resistance was performed. Efficacy of treatment was judged by the attending physician on the basis of a five point chart. Furthermore, a differential blood count was performed before, and 12 weeks after initiation of treatment. Total and specific IgE against all relevant antigens were determined before start of therapy. RESULTS: Airway resistance in patients with response to treatment with omalizumab (responders) was significantly decreased in comparison to patients without clinical benefit (non-responder). The number of eosinophil granulocytes in the peripheral blood was decreased in both groups without significant difference. Response to therapy was associated with younger age and lower levels of specific IgE against the allergen with the highest sIgE-level (seasonal and perennial), but not with the sIgE level of the perennial allergens in general. CONCLUSION: Measurement of airway resistance might be an additional parameter for monitoring response to therapy with omalizumab. High specific IgE levels, for both perennial and concomitant seasonal allergens as well as increasing age, seem to predict less favorable treatment outcomes.

6.
Amino Acids ; 33(3): 511-24, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17072790

RESUMO

We examined the effects of DON [glutamine-analogue and inhibitor of glutamine-requiring enzymes], alanyl-glutamine (regarding its role in neutrophil immunonutrition) and alanyl-glutamine combined with L-NAME, SNAP, DON, beta-alanine and DFMO on neutrophil amino and alpha-keto acid concentrations or important neutrophil immune functions in order to establish whether an inhibitor of *NO-synthase [L-NAME], an *NO donor [SNAP], an analogue of taurine and a taurine transport antagonist [beta-alanine], an inhibitor of ornithine-decarboxylase [DFMO] as well as DON could influence any of the alanyl-glutamine-induced effects. In summary, irrespective of which pharmacological, metabolism-inhibiting or receptor-mediated mechanisms were involved, our results showed that impairment of granulocytic glutamine uptake, modulation of intracellular glutamine metabolisation and/or de novo synthesis as well as a blockade of important glutamine-dependent metabolic processes may led to significant modifications of physiological and immunological functions of the affected cells.


Assuntos
Aminoácidos/metabolismo , Dipeptídeos/metabolismo , Homeostase , Imunocompetência/fisiologia , Cetoácidos/metabolismo , Neutrófilos/metabolismo , Transdução de Sinais/fisiologia , Adulto , Aminoácidos/química , Antibióticos Antineoplásicos/metabolismo , Diazo-Oxo-Norleucina/metabolismo , Eflornitina/metabolismo , Inibidores Enzimáticos/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Cetoácidos/química , Masculino , NG-Nitroarginina Metil Éster/metabolismo , Neutrófilos/química , Neutrófilos/citologia , Doadores de Óxido Nítrico/metabolismo , Oxidantes/metabolismo , Peroxidase/metabolismo , S-Nitroso-N-Acetilpenicilamina/metabolismo , Superóxidos/metabolismo
7.
Nucleic Acids Res ; 29(1): 281-3, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11125113

RESUMO

The TRANSFAC database on transcription factors and their DNA-binding sites and profiles (http://www.gene-regulation.de/) has been quantitatively extended and supplemented by a number of modules. These modules give information about pathologically relevant mutations in regulatory regions and transcription factor genes (PathoDB), scaffold/matrix attached regions (S/MARt DB), signal transduction (TRANSPATH) and gene expression sources (CYTOMER). Altogether, these distinct database modules constitute the TRANSFAC system. They are accompanied by a number of program routines for identifying potential transcription factor binding sites or for localizing individual components in the regulatory network of a cell.


Assuntos
Bases de Dados Factuais , Regulação da Expressão Gênica , Fatores de Transcrição/genética , Sítios de Ligação , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Internet , Fatores de Transcrição/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-27688876

RESUMO

BACKGROUND: Prevalence of vancomycin-resistant enterococci has increased in Germany. Here, we report the cluster of linezolid- and vancomycin-resistant Enterococcus faecium (LVRE) in a German department for hematologic stem cell transplantation (HSCT). METHODS: In this retrospective analysis we included all patients with LVRE in a university-based department for HSCT in 2014 and 2015. Patients chart reviews were used to investigate the epidemiology and clinical outcome. Available LVRE isolates underwent detailed microbiological characterization and genotyping by pulsed-field gel electrophoresis (PFGE). RESULTS: In total, 20 patients with LVRE were identified within the observed time period. All except two patients underwent allogeneic HSCT. Surveillance culture results from incoming patients and chart review revealed that 10 of 20 patients were colonized at hospital admission. Eight of 10 patients with in-hospital acquired LVRE had previous linezolid treatment. Analysis of spatio-temporal patterns showed no evidence for LVRE patient-to-patient or environment-to-patient transmission within the HSCT department. In five cases (25 %) LVRE bloodstream infection occurred. Nine LVRE isolates could be saved for characterization. Eight isolates carried vanA, one isolate vanB. PFGE analysis showed that four different LVRE clones were responsible for the cluster. One single genotype was present in six LVRE isolates whereupon the corresponding patients were all referred from the same hospital to the HSCT department. CONCLUSIONS: This is the first report demonstrating the emergence of LVRE in a German HSCT department. (L)VRE screening at patients' admission and appropriate infection control strategies were sufficient to prevent any transmission. Further studies in this predisposed patient collective are warranted.

9.
Biochim Biophys Acta ; 1537(1): 42-8, 2001 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-11476961

RESUMO

Familial high-density lipoprotein (HDL)-deficiency syndromes are caused by mutations of the ABCA1 gene, coding for the ATP-binding cassette transporter 1. We have developed a homogeneous assay based on 52 primer sets to amplify all 50 ABCA1 exons and approximately 1 kb of its promoter. The assay allows for convenient amplification of the gene from genomic DNA and easy mutational analysis through automatic sequencing. It obviates the need to use mRNA preparations, which were difficult to handle and posed a risk to miss splice junction or promoter mutations. The application of the test to the molecular analysis of a new patient with familial HDL-deficiency (Tangier disease) led to a discovery of two novel ABCA1 mutations: C2665del and C4457T.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Hipolipoproteinemias/genética , Lipoproteínas HDL/sangue , Mutação , Transportador 1 de Cassete de Ligação de ATP , Adulto , Primers do DNA , Humanos , Hipolipoproteinemias/sangue , Masculino , Linhagem , Reação em Cadeia da Polimerase/métodos , Síndrome
11.
Dent Mater ; 6(2): 111-7, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2079171

RESUMO

Both cleaning efficiency and gingival damage depend on the access of toothbrush bristles to sheltered areas and their ability to deliver sufficient force to remove plaque as they travel over tooth surfaces. A mathematical expression was therefore developed which relates bristle properties and features of brush construction to overall brush stiffness, in order to provide a framework for the prediction and systematic investigation of brush performance: Brush stiffness = 0.125E(DBDT)2NTPf/L3. This shows that brush stiffness is predominantly affected by bristle modulus (E), bristle and tuft diameter (DB and DT), the number of tufts (NT), the number of bristles per unit area packed into a tuft hole (Pf = packing factor), and the trim length of bristles (L). Bristle composition and shape had no measurable effect. The 0.125 factor is empirically derived and probably depends on visco-elastic, frictional, and other dynamic effects which were not examined. Thus, this is a first-order approximation, and further work must be done to account for bristle interactions and brushing rate, and to correlate stiffness with a measure of cleaning efficiency.


Assuntos
Análise do Estresse Dentário , Escovação Dentária/instrumentação , Elasticidade , Modelos Teóricos
12.
Amino Acids ; 31(1): 11-26, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16547646

RESUMO

We have examined the effects of N(omega)-nitro-L-arginine-methylester-hydrochloride [L-NAME; inhibitor of nitric oxide synthase], S-nitroso-N-acetyl-penicillamine [SNAP; nitric oxide donor], alpha-difluoro-methyl-ornithine [DFMO; inhibitor of ornithine decarboxylase] arginine or ornithine as well as the combination of arginine or ornithine with L-NAME, SNAP or DFMO on intracellular free amino- and alpha-keto acid profiles and the immune function markers superoxide anion and hydrogen peroxide generation as well as released myeloperoxidase activity in neutrophils (PMN). Although the underlying mechanisms still remain unclear, we believe from our results that nitric oxide as well as polyamine-dependent pathways are involved in the signal transmission of free radical molecule, beneficial nutritional therapy or maleficient pharmacological stress-induced alterations in PMN nutrient composition. Relevant changes in intragranulocyte free amino- and alpha-keto acid homeostasis and metabolism, especially, may be one of the determinants in PMN nutrition that positively or negatively influences and modulate neutrophil host defence capability and immunocompetence.


Assuntos
Aminoácidos/metabolismo , Cetoácidos/metabolismo , Neutrófilos/metabolismo , Óxido Nítrico/metabolismo , Poliaminas/metabolismo , Adulto , Aminoácidos/farmacologia , Eflornitina/farmacologia , Ativação Enzimática/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/metabolismo , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Ativação de Neutrófilo/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Penicilamina/análogos & derivados , Penicilamina/farmacologia , Peroxidase/efeitos dos fármacos , Superóxidos/metabolismo
13.
Amino Acids ; 29(3): 289-300, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16027960

RESUMO

The objective of this study was to determine the dose as well as duration of exposure-dependent effects of L-alanyl-L-glutamine, arginine or taurine on polymorphonuclear neutrophil (PMN) free alpha-keto acid profiles and, in a parallel study, on PMN immune functions. Exogenous L-alanyl-L-glutamine significantly increased PMN alpha-ketoglutarate, pyruvate PMN superoxide anion (O2-) generation, hydrogen peroxide (H2O2) formation and released myeloperoxidase (MPO) activity. Arginine also led to significant increases in alpha-ketoglutarate, pyruvate, MPO release and H2O2 generation. Formation of O2- on the other hand was decreased by arginine. Incubation with taurine resulted in lower intracellular pyruvate and alpha-ketobutyrate levels, decreased O2- and H2O2 formation and a concomitant significantly increased MPO activity. We therefore believe that considerable changes in PMN free-alpha-keto-acid profiles, induced for example by L-alanyl-L-glutamine, arginine or taurine, may be one of the determinants in cell nutrition that considerably modulates the immunological competence of PMN.


Assuntos
Arginina/farmacologia , Dipeptídeos/farmacologia , Cetoácidos/imunologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Taurina/farmacologia , Adulto , Ativação Enzimática/efeitos dos fármacos , Humanos , Líquido Intracelular/metabolismo , Cetoácidos/química , Masculino , Neutrófilos/química , Oxirredução , Peroxidase/efeitos dos fármacos , Fatores de Tempo
14.
Amino Acids ; 28(1): 85-98, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15592942

RESUMO

We have examined the effects of midazolam, Ro 5-4864 (agonist for "peripheral" [p] benzodiazepine receptors [BR]), PK 11195 (antagonist for pBR), flumazenil (antagonist for "central" BR), naloxone (antagonist for opiate receptors) and the combination of midazolam and Ro 5-4864, PK 11195, flumazenil or naloxone on intracellular amino- and alpha-keto acids and the immune function markers superoxide anion (O(2)(-)), hydrogen peroxide (H(2)O(2)) and released myeloperoxidase (MPO) activity in neutrophils (PMN). Only midazolam and Ro 5-4864 led to significant changes in the dynamic PMN free amino- and alpha-keto acid pools. Concerning PMN immune function markers, midazolam and Ro 5-4864 significantly decreased O(2)(-) and H(2)O(2) formation and released MPO. When midazolam and Ro 5-4864 were applied together they appeared to act additively. Pre-incubation with PK 11195 partially neutralized the midazolam effects whereas flumazenil or naloxone showed no effects. We therefore believe that pBR are involved in the signal transmission of anesthetic-induced cellular metabolic changes in PMN.


Assuntos
Aminoácidos/metabolismo , Cetoácidos/metabolismo , Neutrófilos/imunologia , Neutrófilos/metabolismo , Receptores de GABA-A/metabolismo , Adulto , Benzodiazepinonas/farmacologia , Células Cultivadas , Flumazenil/farmacologia , Moduladores GABAérgicos/farmacologia , Agonistas de Receptores de GABA-A , Antagonistas de Receptores de GABA-A , Humanos , Peróxido de Hidrogênio/metabolismo , Isoquinolinas/farmacologia , Masculino , Midazolam/farmacologia , Naloxona/farmacologia , Neutrófilos/efeitos dos fármacos , Peroxidase/efeitos dos fármacos , Peroxidase/metabolismo , Receptores de GABA-A/efeitos dos fármacos , Superóxidos/metabolismo
15.
Am J Physiol ; 274(5): L678-84, 1998 05.
Artigo em Inglês | MEDLINE | ID: mdl-9612282

RESUMO

Vascular endothelial growth factor (VEGF) is a key regulator of vasculo- and angiogenesis. Earlier studies demonstrated a permeability-increasing effect of VEGF in skin tests, leading to its other name, vascular permeability factor. We wondered whether VEGF-induced hyperpermeability was a direct effect of VEGF on endothelial cells and studied the permeability of human and porcine endothelial cell monolayers in a well-characterized in vitro system. VEGF increased the hydraulic conductivity up to 20-fold and simultaneously decreased the albumin reflection coefficient. This effect occurred after a delay of 150 min, although VEGF-induced early endothelial cell activation was verified by enhanced inositol phosphate accumulation within 5 min and increased P-selectin expression within 15 min. Platelet-derived growth factor and granulocyte-macrophage colony-stimulating factor, two endothelial cell nonspecific mitogens, also stimulated phosphatidylinositol metabolism and P-selectin expression; however, they had no effect on endothelial permeability. The increase in intracellular cyclic nucleotide levels of human endothelial monolayers abolished VEGF-induced endothelial hyperpermeability. In summary, VEGF increased endothelial permeability by a direct action on endothelial cells. Based on the pattern of endothelial cell activation by growth factors, VEGF appears to be a unique stimulus.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Fatores de Crescimento Endotelial/farmacologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Linfocinas/farmacologia , Células Cultivadas , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Selectina-P/metabolismo , Fosfatidilinositóis/metabolismo , Fator de Crescimento Derivado de Plaquetas/farmacologia , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
16.
J Immunol ; 159(4): 1970-6, 1997 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9257863

RESUMO

Infection of endothelial cells by Listeria monocytogenes is an essential step in the pathogenesis of listeriosis. Listeriolysin (Hly) is one of its major virulence factors. In the early phase of the disease polymorphonuclear leukocytes (PMN) substantially contribute to the nonspecific anti-listerial resistance. We characterized the effects of L. monocytogenes on the expression of endothelial adhesion molecules and on subsequent PMN adhesion to cultured HUVEC. P-selectin, E-selectin, intracellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) were up-regulated in HUVEC after cell incubation with L. monocytogenes (wild type), but not with the nonpathogenic Listeria innocua strain. P-selectin expression peaked after 30 min and could be mimicked with similar kinetics by exposure to L. innocua engineered to produce large amounts of Hly or by addition of purified Hly. Listeriolysin production, however, was not necessary for an up-regulation of E-selectin after 6 h or of ICAM-1 and VCAM-1 after 18 to 24 h in HUVEC, because L. monocytogenes defective for Hly synthesis was almost as effective as the wild type. Listeria-induced up-regulation of endothelial adhesion molecules was accompanied by an increased binding of PMN to infected HUVEC. PMN adhesion was significantly reduced in the presence of anti-beta2 integrin, anti-E-selectin, and anti-ICAM-1, but not anti-VCAM-1 Abs. Our data indicate that infection of endothelial cells with L. monocytogenes induced up-regulation of adhesion molecules by two different mechanisms: a Hly-dependent up-regulation of P-selectin and a Hly-independent expression of E-selectin, ICAM-1, and VCAM-1. The ability of L. monocytogenes to stimulate PMN adhesion to endothelial cells may be an important mechanism in the pathogenesis of severe listeriosis.


Assuntos
Moléculas de Adesão Celular/biossíntese , Endotélio Vascular/metabolismo , Listeria monocytogenes/fisiologia , Neutrófilos/fisiologia , Adesão Celular , Células Cultivadas , Selectina E/biossíntese , Endotélio Vascular/citologia , Humanos , Molécula 1 de Adesão Intercelular/biossíntese , Regulação para Cima , Molécula 1 de Adesão de Célula Vascular/biossíntese
17.
Lung ; 174(3): 181-94, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8830194

RESUMO

The regulation of endothelial permeability is poorly understood. An increase in endothelial permeability in the pulmonary microvasculature, however, is critical in noncardiogenic pulmonary edema and other diffuse inflammatory reactions. In the present study thrombin and Escherichia coli hemolysin (HlyA), a membrane-perturbing bacterial exotoxin, were used to alter hydraulic permeability of porcine pulmonary artery and human endothelial cell monolayers. We also investigated the pharmacological approach of adenylyl cyclase activation/phosphodiesterase (PDE) inhibition to block endothelial hyperpermeability. Thrombin (1-5 units/ml) and HlyA (0.5-3 hemolytic units/ml) dose and time dependently (> 15 min) increased endothelial permeability. Forskolin, cholera toxin, and prostaglandin E1, which all stimulate adenylyl cyclase activity, abrogated this effect. One mM dibutyryl cAMP, a cell membrane-permeable cAMP analogue, was similarly active. Endothelial hyperpermeability was also reduced dose dependently by inhibitors of different PDE isoenzymes (motapizone, rolipram, and zardaverine, which block PDE3 and/or PDE4). The effectiveness of PDE inhibitors was increased in the presence of adenylyl cyclase activators. Analysis of cyclic nucleotide hydrolyzing PDE activity in lysates of human umbilical vein endothelial cells showed high activities of PDE isoenzymes 2, 3, and 4. Consistent with the functional data PDE3 and PDE4 were the major cAMP hydrolysis enzymes in intact endothelial cells. We conclude that the hyperpermeability of pulmonary endothelial monolayers, evoked by thrombin or HlyA, can be blocked by the simultaneous activation of adenylyl cyclase and inhibition of PDEs, especially of PDE3 and PDE4. The demonstration of PDE isoenzymes 2-4 in human endothelial cells will help optimize this therapeutic approach.


Assuntos
3',5'-AMP Cíclico Fosfodiesterases/fisiologia , Adenilil Ciclases/metabolismo , Endotélio Vascular/metabolismo , Proteínas de Escherichia coli , Diester Fosfórico Hidrolases/fisiologia , Animais , Proteínas de Bactérias/farmacologia , Toxinas Bacterianas/farmacologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/fisiologia , Células Cultivadas , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3 , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Endotélio Vascular/citologia , Endotélio Vascular/enzimologia , Ativação Enzimática , Proteínas Hemolisinas/farmacologia , Humanos , Inibidores de Fosfodiesterase/farmacologia , Artéria Pulmonar/citologia , Artéria Pulmonar/metabolismo , Suínos , Trombina/farmacologia , Veias Umbilicais/citologia , Veias Umbilicais/metabolismo
18.
J Immunol ; 157(9): 4133-40, 1996 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-8892649

RESUMO

Adhesion of polymorphonuclear leukocytes (PMN) to endothelial cells is an essential step in inflammatory reactions. We characterized the effects of two important bacterial exotoxins, Escherichia coli hemolysin (HlyA) and Staphylococcus aureus alpha-toxin (S. alpha-toxin) on PMN adhesion to cultured HUVEC. Both toxins increased adherence of human PMN to HUVEC in a dose- and time-dependent manner, peaking after 30 min at 0.01 hemolytic units/ml HlyA or 0.5 microg/ml S. alpha-toxin. Pretreatment of HUVEC with anti-P-selectin mAbs or of PMN with anti-CD11b/CD18 mAb reduced HlyA- and S. alpha-toxin-related cell adhesion significantly. Increased P-selectin expression on toxin-treated endothelial cells was demonstrated by cell surface ELISA. Compared with endotoxin, HlyA and S. alpha-toxin did not induce the expression of E-selectin, ICAM-1, or VCAM-1. FACS analysis showed increased CD11b/CD18 expression on HlyA-, but not on S. alpha-toxin-stimulated PMN. Platelet-activating factor, an important costimulatory factor for PMN adhesion and activation, was also active in the exotoxin-stimulated adhesion system, as evidenced by studies using the platelet-activating factor receptor antagonist BN50727. HPLC analysis of endothelial cell extracts confirmed enhanced toxin-mediated PAF synthesis. The capacity of exotoxins to stimulate PMN adhesion to endothelial cells may be relevant in patients with severe local or systemic bacterial infections.


Assuntos
Proteínas de Bactérias/farmacologia , Toxinas Bacterianas/farmacologia , Endotélio Vascular/citologia , Proteínas de Escherichia coli , Escherichia coli/metabolismo , Proteínas Hemolisinas/farmacologia , Neutrófilos/efeitos dos fármacos , Receptores de Superfície Celular , Receptores Acoplados a Proteínas G , Staphylococcus aureus/metabolismo , Azepinas/farmacologia , Antígenos CD18/biossíntese , Antígenos CD18/genética , Adesão Celular/efeitos dos fármacos , Moléculas de Adesão Celular/biossíntese , Moléculas de Adesão Celular/genética , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Antígeno de Macrófago 1/biossíntese , Antígeno de Macrófago 1/genética , Neutrófilos/citologia , Neutrófilos/metabolismo , Fator de Ativação de Plaquetas/biossíntese , Fator de Ativação de Plaquetas/genética , Glicoproteínas da Membrana de Plaquetas/efeitos dos fármacos , Tienopiridinas , Triazóis/farmacologia , Veias Umbilicais
19.
Bioinformatics ; 17(11): 1053-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11724734

RESUMO

UNLABELLED: TRANSPATH is an information system on gene-regulatory pathways, and an extension module to the TRANSFAC database system (Wingender et al., Nucleic Acids Res., 28, 316-319, 2000). It focuses on pathways involved in the regulation of transcription factors in different species, mainly human, mouse and rat. Elements of the relevant signal transduction pathways like complexes, signaling molecules, and their states are stored together with information about their interaction in an object-oriented database. The database interface provides clickable maps and automatically generated pathway cascades as additional ways to explore the data. All information is validated with references to the original publications. Also, references to other databases are provided (TRANSFAC, SWISS-PROT, EMBL, PubMed and others). AVAILABILITY: The database is available over (http://transpath.gbf.de) for interactive perusal. As an exchange format for the data, eXtensible Markup Language (XML) flatfiles and a Document Type Definition (DTD) are provided.


Assuntos
Inteligência Artificial , Bases de Dados Factuais , Transdução de Sinais , Algoritmos , Biologia Computacional , Gráficos por Computador , Simulação por Computador
20.
Am J Physiol ; 270(3 Pt 1): C778-85, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8638657

RESUMO

Regulation of endothelial permeability is poorly understood. Previous studies have shown that endothelial cells contain phosphodiesterase (PDE) isoenzymes II-IV and that simultaneous adenylate cyclase activation and/or PDE inhibition blocked endothelial hyperpermeability (J.Clin.Invest. 91: 1421-1428, 1993). We now focused on a possible role for guanosine 3',5'-cyclic monophosphate (cGMP)-dependent mechanisms and studied H2O2-exposed porcine pulmonary artery endothelial cell monolayers. Pretreatment of cells with different nitric oxide (NO) donors or atrial natriuretic peptide (ANP) increased endothelial cGMP-content severalfold and blocked H2O2-related effects on permeability; opposite results were obtained with a NO synthase inhibitor. Determination of cGMP degradation in nitroprusside-exposed endothelial cells identified PDE II as the major cGMP metabolizing pathway, whereas PDE III and IV contributed little or nothing. Inhibition of PDE II reduced H2O2-related endothelial hyperpermeability, an effect that could be enhanced synergistically by simultaneous guanylate cyclase activation. In summary, these studies indicate that cGMP-dependent mechanisms (NO donors, ANP, and dibutyryl-cGMP) blocked H2O2-related increases in endothelial permeability. The major cGMP degrading pathway in endothelial cells was PDE II, thereby substituting the missing PDE V in these cells. Simultaneous guanylate cyclase activation and/or PDE II inhibition may be a valuable approach to treat endothelial hyperpermeability.


Assuntos
Permeabilidade da Membrana Celular , Endotélio Vascular/fisiologia , Óxido Nítrico/fisiologia , Diester Fosfórico Hidrolases/metabolismo , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Células Cultivadas , Condutividade Elétrica , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/enzimologia , Inibidores Enzimáticos/farmacologia , Escherichia coli , Proteínas Hemolisinas/farmacologia , Peróxido de Hidrogênio/farmacologia , Isoenzimas/metabolismo , Cinética , Molsidomina/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Nitroarginina , Nitroglicerina/farmacologia , Nitroprussiato/farmacologia , Artéria Pulmonar , Suínos
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