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1.
Cardiol Res Pract ; 2022: 6538296, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35111341

RESUMO

BACKGROUND: Acute coronary syndrome (ACS) causes pathophysiological changes in exercise capacity, N-terminal part of pro-brain natriuretic peptide (NT-proBNP), and adiponectin that impact the course of coronary artery disease and clinical outcomes after cardiac rehabilitation (CR). However, the serial changes and the relationship between the changes in these parameters for a prolonged term remain uninvestigated. METHODS: Eighty-one patients with ACS underwent a three- or four-week CR program after acute care and were followed up for 12 months. Exercise capacity on a cycle ergometer and blood levels of NT-proBNP and adiponectin were determined before and after CR as well as at the 12-month follow-up. RESULTS: Exercise capacity increased from 100 watts (in median) before CR to 138 watts after CR and 150 watts at 12 months. The NT-proBNP level (526 pg/ml before CR) remained almost unchanged after CR (557 pg/ml) and then decreased at 12 months (173 pg/ml). The adiponectin level (14.5 µg/ml before CR) increased after CR (16.0 µg/ml) and at 12 months (17.2 µg/ml). There was no significant correlation among the changes in these parameters at each observation time point. CONCLUSION: During the observation period from before CR to the 12-month follow-up, exercise capacity, NT-proBNP, and adiponectin underwent significant changes; however, these changes were independent from each other and not correlated linearly, and they provide complementary information in clinical practice. Thus, all these parameters should be included and determined at different time points for a prolonged period of time.

2.
Biomark Med ; 8(6): 777-89, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25224934

RESUMO

BACKGROUND: As complex disease, heart failure is associated with various pathophysiological and biochemical disorders. No single biomarker is able to display all these characteristics. Therefore, we evaluated a multimarker panel together with the biochemical gold-standard NT-proBNP. Part of the panel are markers for angiogenesis (Endostatin, IBP-4, IBP-7, sFlt-1 as antiangiogenetic factors and PLGF as angiogenectic factor), myocyte stress (GDF-15), extracellular matrix remodelling (galectin-3, mimecan and TIMP-1), inflammation (galectin-3) and myocyte injury (hs-TnT). METHODS: All markers (Roche Diagnostics, Penzberg, Germany) were assessed in a cohort of 149 patients with chronic heart failure and 84 healthy controls. RESULTS: All markers were positively correlated with ln NT-proBNP (each p < 0.05). Furthermore, they were significantly elevated in patients with chronic heart failure (each p < 0.05). All markers increased significantly with severity of LV dysfunction and severity of New York Heart Association class (each p < 0.05), except for PLGF and Mimecan (each p = NS). With the exception of endostatin, mimecan and PLGF, all other markers were further significant predictors for all-cause mortality in a 3-year follow-up. In a multimarker approach of the five biomarkers with the best performance (NT-proBNP, hs-TnT, TIMP-1, GDF-15 and IBP-4), the event rate was superior to NT-proBNP alone and increased significantly and progressively with the number of elevated biomarkers. CONCLUSION: All emerging markers increased stepwise with the severity of symptoms and LV dysfunction and offer important prognostic information in chronic heart failure, except for PLGF and mimecan. Five biomarkers with different pathophysiological background incorporated additive prognostic value in heart failure. Prognostication in heart failure may be further improved through a multimarker approach.


Assuntos
Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Proteínas Sanguíneas , Doença Crônica , Endostatinas/sangue , Feminino , Seguimentos , Galectina 3/sangue , Galectinas , Fator 15 de Diferenciação de Crescimento/sangue , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Fator de Crescimento Placentário , Proteínas da Gravidez/sangue , Prognóstico , Taxa de Sobrevida , Inibidor Tecidual de Metaloproteinase-1/sangue , Troponina T/sangue , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Disfunção Ventricular Esquerda/sangue , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/mortalidade , Disfunção Ventricular Esquerda/fisiopatologia
3.
Atherosclerosis ; 236(2): 292-300, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25112800

RESUMO

BACKGROUND: Anemia has been shown to be a risk factor for coronary artery disease and mortality. The involvement of body iron stores in the development of CAD remains controversial. So far, studies that examined hemoglobin and parameters of iron metabolism simultaneously do not exist. METHODS AND RESULTS: Hemoglobin and iron status were determined in 1480 patients with stable angiographic coronary artery disease (CAD) and in 682 individuals in whom CAD had been ruled out by angiography. The multivariate adjusted odds ratios (OR) for CAD in the lowest quartiles of hemoglobin and iron were 1.62 (95%CI: 1.22-2.16), and 2.05 (95%CI: 1.51-2.78), respectively compared to their highest gender-specific quartiles. The fully adjusted ORs for CAD in the lowest quartiles of transferrin saturation, ferritin (F) and soluble transferrin receptor (sTfR)/log10F index were 1.69 (95%CI: 1.25-2.27), 1.98 (95%CI: 1.48-2.65), and 1.64 (95%CI: 1.23-2.18), respectively compared to their highest gender-specific quartiles. When adjusting in addition for iron and ferritin the OR for CAD in the lowest quartiles of hemoglobin was still 1.40 (95%CI: 1.04-1.90) compared to the highest gender-specific quartiles. Thus, the associations between either iron status or low hemoglobin and CAD appeared independent from each other. The sTfR was only marginally associated with angiographic CAD. CONCLUSIONS: Both low hemoglobin and iron depletion are independently associated with angiographic CAD.


Assuntos
Anemia/epidemiologia , Angiografia Coronária , Doença das Coronárias/epidemiologia , Hemoglobinas/análise , Ferro/metabolismo , Adulto , Idoso , Proteína C-Reativa/análise , Comorbidade , Doença das Coronárias/sangue , Doença das Coronárias/diagnóstico por imagem , Estudos Transversais , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Feminino , Ferritinas/sangue , Alemanha/epidemiologia , Humanos , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos Prospectivos , Receptores da Transferrina/sangue , Fumar/epidemiologia , Transferrina/análise
4.
Hum Mol Genet ; 23(9): 2498-510, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24345515

RESUMO

Waist circumference (WC) and waist-to-hip ratio (WHR) are surrogate measures of central adiposity that are associated with adverse cardiovascular events, type 2 diabetes and cancer independent of body mass index (BMI). WC and WHR are highly heritable with multiple susceptibility loci identified to date. We assessed the association between SNPs and BMI-adjusted WC and WHR and unadjusted WC in up to 57 412 individuals of European descent from 22 cohorts collaborating with the NHLBI's Candidate Gene Association Resource (CARe) project. The study population consisted of women and men aged 20-80 years. Study participants were genotyped using the ITMAT/Broad/CARE array, which includes ∼50 000 cosmopolitan tagged SNPs across ∼2100 cardiovascular-related genes. Each trait was modeled as a function of age, study site and principal components to control for population stratification, and we conducted a fixed-effects meta-analysis. No new loci for WC were observed. For WHR analyses, three novel loci were significantly associated (P < 2.4 × 10(-6)). Previously unreported rs2811337-G near TMCC1 was associated with increased WHR (ß ± SE, 0.048 ± 0.008, P = 7.7 × 10(-9)) as was rs7302703-G in HOXC10 (ß = 0.044 ± 0.008, P = 2.9 × 10(-7)) and rs936108-C in PEMT (ß = 0.035 ± 0.007, P = 1.9 × 10(-6)). Sex-stratified analyses revealed two additional novel signals among females only, rs12076073-A in SHC1 (ß = 0.10 ± 0.02, P = 1.9 × 10(-6)) and rs1037575-A in ATBDB4 (ß = 0.046 ± 0.01, P = 2.2 × 10(-6)), supporting an already established sexual dimorphism of central adiposity-related genetic variants. Functional analysis using ENCODE and eQTL databases revealed that several of these loci are in regulatory regions or regions with differential expression in adipose tissue.


Assuntos
Circunferência da Cintura/genética , Adiposidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Relação Cintura-Quadril , População Branca , Adulto Jovem
5.
Int J Infect Dis ; 15(6): e422-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21511507

RESUMO

OBJECTIVES: The aim of this study is to highlight the importance of infections caused by members of the genera Pseudallescheria/Scedosporium in HIV-positive patients. METHODS: We describe a case of a fatal scedosporiosis in a treatment-naïve HIV patient and review all previously reported cases of pseudallescheriosis/scedosporiosis from a search of the PubMed and Deutsches Institut für Medizinische Dokumentation und Information (DIMDI) databases, applying the terms 'Pseudallescheria', 'Scedosporium', 'Allescheria', 'Monosporium', 'Petriellidium', 'boydii', 'prolificans', 'inflatum', cross-referenced with 'HIV' and 'AIDS'. RESULTS: Detection of Scedosporium and Pseudallescheria species has been reported in 22 HIV-positive patients. Fourteen isolates belonged to the Pseudallescheria boydii complex and eight to Scedosporium prolificans. Invasive scedosporiosis (IS) was proven in 54.5% of the patients. Among them dissemination was observed in 66.7%. Pseudallescheria/Scedosporium species were mainly isolated from male individuals. Patients with proven IS showed CD4+ cell counts <100/µl and a higher co-infection rate as compared to colonized patients. Patients with central nervous system (CNS) manifestations showed CD4+ cell counts <50/µl. The mortality rate for patients with proven IS was 75% and was 100% for patients with dissemination/CNS manifestations. The fatality rate for patients treated with antifungal drugs plus surgery was lower compared to patients treated with antimycotic agents alone. CONCLUSIONS: IS only occurred in HIV-positive patients with a strongly impaired immune system. The survival rates of patients with advanced HIV disease and invasive scedosporiosis can be improved by rapid diagnosis by biopsy and requires complex therapy with a combination of active antifungal drugs, surgery and supportive immune augmentation.


Assuntos
Antifúngicos/uso terapêutico , Infecções por HIV/complicações , Micetoma/diagnóstico , Micetoma/tratamento farmacológico , Pseudallescheria/classificação , Scedosporium/classificação , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Adulto , Evolução Fatal , Feminino , Humanos , Micetoma/complicações , Micetoma/microbiologia , Reação em Cadeia da Polimerase , Pseudallescheria/genética , Pseudallescheria/isolamento & purificação , Radiografia , Scedosporium/genética , Scedosporium/isolamento & purificação , Toxoplasmose Cerebral/complicações , Toxoplasmose Cerebral/diagnóstico por imagem
6.
Korean J Parasitol ; 49(4): 365-71, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22355203

RESUMO

In Nigeria, malaria causes up to 11% of maternal mortality. Our main aim was to find out the most common mosquito control measures employed by the pregnant women in Lagos and their effects on malaria infection. The study was carried out over a period of 6 months during which trained interviewers administered questionnaires to 400 pregnant women. The prevalence of malaria was 8.4%. There was no significant association between the prevalence of malaria and age, level of education, or occupation of the participants. Pregnant women in the age range 26-30 had the mean parasite density (409.9 ± 196.80). Insecticide spray (32.8%), mosquito coil (27.5%), and insecticide-treated nets (ITN) (15.5%) were the major mosquito control measures employed by the participants while the prevalence of infection among them were 2.3%, 6.2%, and 3.2%, respectively (P<0.05). Only 18.3% of the women had taken more than one dose of intermittent preventive treatment (IPT), while another 11.8% had taken a single dose. The infection rate among them was 4.1% and 6.4%, respectively. Malaria prevalence was highest among those who had not received any dose of IPT (10%). This study showed that the use of ITN and IPT among the pregnant women were still unacceptably low. It also showed that the use of insecticide spray which was the most common malaria control measure adopted by the participants was effective despite the fact that it is not a National Malaria Control Policy. We recommend that a sustained integrated mosquito management and public education should be strengthened in Nigeria.


Assuntos
Culicidae , Insetos Vetores , Malária/prevenção & controle , Controle de Mosquitos/métodos , Plasmodium/fisiologia , Complicações Parasitárias na Gravidez/prevenção & controle , Adolescente , Adulto , Animais , Culicidae/parasitologia , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Insetos Vetores/parasitologia , Inseticidas , Malária/epidemiologia , Nigéria/epidemiologia , Gravidez , Complicações Parasitárias na Gravidez/epidemiologia , Cuidado Pré-Natal , Prevalência , Saúde Pública , Inquéritos e Questionários , Adulto Jovem
7.
J Dtsch Dermatol Ges ; 9(6): 444-7, 2011 Jun.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-21166783

RESUMO

Varicella has the highest contagiosity index of all viral diseases. We report an endemic outbreak of varicella among 4 Indian students in Magdeburg in November and December 2008. An initially severe course was observed in three of these patients with a negative vaccination status. Large vesicular skin lesions with a diameter of up to 8 mm were found in all patients. Molecular genetic tests revealed African/Indian clade 5 in 2 patients, although the European clades (i.e., clade 1 and 3) are the most common in Germany, accounting for 85 %. All patients recovered without any complications after administration of intravenous aciclovir at a dosage of 10 mg per kg body weight. Although isolated cases of varicella are not notifiable according to the German Protection against Infection Act, endemic outbreaks must be reported to the appropriate health surveillance authorities.


Assuntos
Varicela/diagnóstico , Varicela/virologia , Surtos de Doenças/prevenção & controle , Emigração e Imigração , Herpesvirus Humano 3/isolamento & purificação , Aciclovir/uso terapêutico , Antivirais/uso terapêutico , Varicela/tratamento farmacológico , Alemanha , Herpesvirus Humano 3/genética , Humanos , Índia , Resultado do Tratamento
8.
J Infect Dev Ctries ; 3(9): 685-94, 2009 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-19858570

RESUMO

BACKGROUND: Salmonella spp. are recognized as some of the most common causes of enteritis worldwide. This study aimed to identify clinically isolated S. Typhimurium in western Kenya and to assess antimicrobial resistance profiles and strain inter-relatedness. METHODS: The study was performed in rural Maseno, Nyanza province in Kenya, between February 2004 and June 2005. Sixty-three patients with diarrhoea and fever were recruited. S. Typhimurium isolates were confirmed using serotyping, biochemical testing, and 16S rRNA sequencing. Susceptibility to 20 antimicrobials was determined and specific resistance genes were identified by polymerase chain reaction (PCR). Strain diversity was further analyzed using pulsed-field gel electrophoresis (PFGE), fluorescence amplified fragment length polymorphism (fAFLP), and multi-locus-variable-number-tandem regions (MLVNTR). RESULTS: Twenty S. Typhimurium strains were isolated in the course of the study and their identity was confirmed by 16S rRNA gene sequencing. All 20 S. Typhimurium strains were resistant to ampicillin, streptomycin and sulfamethoxazole; ciprofloxacin resistance and phage DT104 were not detected. PFGE, plasmid profiling, and analysis of selected VNTR loci revealed further heterogeneity among the strains in the study. CONCLUSION: S. Typhimurium was commonly isolated from patients with diarrhoea and fever in Maseno. Considerable phenotypic and genotypic diversity was observed among isolates, suggesting that strains belonging to multiple lineages are responsible for disease in the study region. Multiple resistance was common and mediated by a variety of resistance genes but not by phage DT104.


Assuntos
Técnicas de Tipagem Bacteriana , Farmacorresistência Bacteriana , Infecções por Salmonella/epidemiologia , Infecções por Salmonella/microbiologia , Salmonella typhimurium/classificação , Salmonella typhimurium/efeitos dos fármacos , Análise por Conglomerados , Impressões Digitais de DNA , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Diarreia/epidemiologia , Diarreia/microbiologia , Genes Bacterianos , Variação Genética , Genótipo , Humanos , Quênia/epidemiologia , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Salmonella typhimurium/genética , Salmonella typhimurium/isolamento & purificação , Análise de Sequência de DNA , Sorotipagem
9.
Atherosclerosis ; 205(1): 192-6, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19131063

RESUMO

The 12/15-lipoxygenase plays a janus-role in inflammation with pro-inflammatory and anti-inflammatory effects in cell systems and even opposite effects on atherosclerosis in two different animal species. Screening of the human 15-lipoxygenase (ALOX15) gene detected a polymorphic C to T substitution at position c.-292, which led to three times higher ALOX15 activity in macrophages and showed a trend to be atheroprotective in a small case-control study for coronary artery disease (CAD). A second polymorphism at position c.1693C>T leading to an T560M exchange and an inactive enzyme was recently associated with increased CAD. We now investigated whether these polymorphisms or a certain haplotype of ALOX15 are associated with myocardial infarction (MI) in a case-control subset from the population-based MONIKA/KORA cohort S3. Six polymorphisms in ALOX15 were analyzed in 2629 participants to cover all major haplotypes with a frequency higher than 1% in the Caucasian population. None of the polymorphism was associated with MI but a rare ALOX15 haplotype showed a significant protective effect on the risk for MI (p=0.03). However, none of the polymorphisms or haplotypes was associated with CRP levels. These data suggest that ALOX15 may play a less prominent role during later stages of atherosclerosis involving atherothrombotic mechanisms than eventually during early plaque development.


Assuntos
Araquidonato 15-Lipoxigenase/genética , Araquidonato 15-Lipoxigenase/fisiologia , Infarto do Miocárdio/genética , Polimorfismo Genético , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Predisposição Genética para Doença , Haplótipos , Humanos , Inflamação , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Trombose/metabolismo
10.
J Dtsch Dermatol Ges ; 6(3): 210-3, 2008 Mar.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-18201221

RESUMO

A 21-year-old immunocompetent woman developed a cowpox infec-tion,while working as a veterinarian's assistant in a rural area. She had never received vaccinia immunization and came in contact with a fatally-infected house cat. Under symptomatic treatment, the infection remained localized to one cheek and cleared over 3 weeks with substantial dermal-subcutaneous tissue destruction. Orthopoxvirus detection by PCR is a modern diagnostic standard, in addition to identification by negative-contrast electron microscopy. A promising therapeutic option is cidofovir, but this virostatic drug is not yet approved for the treatment of cowpox.


Assuntos
Doenças do Gato/diagnóstico , Doenças do Gato/transmissão , Varíola Bovina/diagnóstico , Varíola Bovina/transmissão , Dermatopatias Virais/diagnóstico , Dermatopatias Virais/transmissão , Adulto , Animais , Gatos , Varíola Bovina/veterinária , Feminino , Humanos , Dermatopatias Virais/terapia
11.
Nature ; 449(7164): 862-6, 2007 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-17943123

RESUMO

Integrins are important mammalian receptors involved in normal cellular functions as well as pathogenesis of chronic inflammation and cancer. We propose that integrins are exploited by the gastric pathogen and type-1 carcinogen Helicobacter pylori for injection of the bacterial oncoprotein cytotoxin-associated gene A (CagA) into gastric epithelial cells. Virulent H. pylori express a type-IV secretion pilus that injects CagA into the host cell; CagA then becomes tyrosine-phosphorylated by Src family kinases. However, the identity of the host cell receptor involved in this process has remained unknown. Here we show that the H. pylori CagL protein is a specialized adhesin that is targeted to the pilus surface, where it binds to and activates integrin alpha5beta1 receptor on gastric epithelial cells through an arginine-glycine-aspartate motif. This interaction triggers CagA delivery into target cells as well as activation of focal adhesion kinase and Src. Our findings provide insights into the role of integrins in H.-pylori-induced pathogenesis. CagL may be exploited as a new molecular tool for our further understanding of integrin signalling.


Assuntos
Proteínas de Bactérias/metabolismo , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Helicobacter pylori/metabolismo , Integrina alfa5beta1/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/química , Linhagem Celular , Ativação Enzimática , Células Epiteliais/enzimologia , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Fímbrias Bacterianas/metabolismo , Helicobacter pylori/patogenicidade , Oligopeptídeos/metabolismo , Fosforilação , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas
12.
J Med Microbiol ; 56(Pt 10): 1370-1376, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17893176

RESUMO

Helicobacter pylori infections can be effectively treated with clarithromycin, a macrolide, in combination with other antibiotics, such as amoxicillin, tetracycline or metronidazole. The failure of H. pylori eradication is mainly associated with macrolide-resistant strains. Three point mutations (A2142G/C, A2143G, T2182C) in the peptidyltransferase region of domain V of the 23S rRNA have been described as being associated with clarithromycin resistance. Therefore, the determination of clarithromycin resistance by pyrosequencing was evaluated. H. pylori from 81 gastric biopsies was cultured and clarithromycin resistance was determined by Etest, as well as by pyrosequencing technology (PSQ 96 system; Biotage). The respective mutations were set in relation to the MIC measured in microg ml(-1) by Etest. In this study, point mutations in positions 2142 and 2143 were associated with clarithromycin resistance. Mutations in position 2182 did not contribute to clarithromycin resistance. In addition, from 22 out of the 81 biopsies, clarithromycin resistance was determined directly without culturing H. pylori to save additional time. Identical results were obtained as compared to resistance testing with pure H. pylori strains. All results obtained by pyrosequencing were evaluated by Sanger sequencing. The data show that pyrosequencing to detect point mutation is a fast and reliable method for determining clarithromycin resistance in H. pylori, and provides the same results as the Etest.


Assuntos
Antibacterianos/farmacologia , Claritromicina/farmacologia , Farmacorresistência Bacteriana/genética , Helicobacter pylori/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Biópsia , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Helicobacter pylori/isolamento & purificação , Humanos , Mutação Puntual , RNA Bacteriano/genética , RNA Ribossômico 23S/genética , Sensibilidade e Especificidade , Análise de Sequência de DNA
13.
FEMS Microbiol Lett ; 274(1): 9-16, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17573935

RESUMO

Binding of Campylobacter jejuni and Campylobacter coli to host fibronectin is mediated by the 37 kDa outer membrane protein CadF. Immunoblot analysis of 58 C. jejuni and C. coli isolates of human and animal origin showed that CadF is expressed in every strain. In most C. jejuni isolates, a 37 kDa band (p37) and a less-prominent 32 kDa band (p32) reacted with the antibodies. In C. coli isolates, CadF was consistently larger with sizes of 39 kDa (p39) and 34 kDa (p34), respectively. PCR analysis and sequencing revealed the presence of a 39-bp insertion sequence in the cadF gene of C. coli strains, explaining the increased molecular size. Infection assays revealed that C. jejuni bound and invaded INT-407 epithelial cells much more efficiently than C. coli and that this difference was considerably reduced in isogenic cadF mutants. These results demonstrate that CadF is an important pathogenicity factor. The difference between CadF of C. jejuni and C. coli may potentially be exploited to discriminate these species in food and clinical specimens.


Assuntos
Proteínas da Membrana Bacteriana Externa/fisiologia , Campylobacter coli/patogenicidade , Campylobacter jejuni/patogenicidade , Proteínas de Transporte/fisiologia , Sequência de Aminoácidos , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/genética , Campylobacter coli/genética , Campylobacter coli/metabolismo , Campylobacter jejuni/genética , Campylobacter jejuni/metabolismo , Proteínas de Transporte/química , Proteínas de Transporte/genética , Linhagem Celular , Humanos , Imuno-Histoquímica , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Análise de Sequência de Proteína
14.
Cell Microbiol ; 9(10): 2431-44, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17521326

RESUMO

Host cell invasion of the food-borne pathogen Campylobacter jejuni is one of the primary reasons of tissue damage in humans but molecular mechanisms are widely unclear. Here, we show that C. jejuni triggers membrane ruffling in the eukaryotic cell followed by invasion in a very specific manner first with its tip followed by the flagellar end. To pinpoint important signalling events involved in the C. jejuni invasion process, we examined the role of small Rho family GTPases. Using specific GTPase-modifying toxins, inhibitors and GTPase expression constructs we show that Rac1 and Cdc42, but not RhoA, are involved in C. jejuni invasion. In agreement with these observations, we found that internalization of C. jejuni is accompanied by a time-dependent activation of both Rac1 and Cdc42. Finally, we show that the activation of these GTPases involves different host cell kinases and the bacterial fibronectin-binding protein CadF. Thus, CadF is a bifunctional protein which triggers bacterial binding to host cells as well as signalling leading to GTPase activation. Collectively, our results suggest that C. jejuni invade host target cells by a unique mechanism and the activation of the Rho GTPase members Rac1 and Cdc42 plays a crucial role in this entry process.


Assuntos
Campylobacter jejuni/fisiologia , Células Epiteliais/microbiologia , Proteína cdc42 de Ligação ao GTP/fisiologia , Proteínas rac1 de Ligação ao GTP/fisiologia , Aderência Bacteriana , Proteínas da Membrana Bacteriana Externa/fisiologia , Campylobacter jejuni/metabolismo , Campylobacter jejuni/ultraestrutura , Proteínas de Transporte/fisiologia , Linhagem Celular , Ativação Enzimática , Células Epiteliais/metabolismo , Flagelos/fisiologia , Interações Hospedeiro-Patógeno , Humanos , Microscopia Eletrônica de Varredura
15.
J Med Microbiol ; 56(Pt 6): 755-761, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17510259

RESUMO

Bacterial vaginosis (BV) is a prevalent infection in women of reproductive age associated with numerous sequelae, including preterm delivery, amniotic fluid infections and an increased risk of acquiring sexually transmitted diseases. The vaginal microbiota in BV patients is characterized by a shift from lactobacilli to a diverse spectrum of mostly anaerobic bacteria. In this study, terminal restriction fragment length polymorphism (T-RFLP) was used to characterize the vaginal bacterial communities from 50 women with BV and 20 healthy subjects. In the BV samples, 23 species or phylotypes from 17 genera could be identified, including Atopobium vaginae, Megasphaera sp., Lactobacillus iners, Gardnerella vaginalis and three recently described phylotypes from the order Clostridiales. The number of detected species or phylotypes was on average 6.3 per sample (range 2-14). In contrast, in normal samples, only Lactobacillus species could be identified. In conclusion, T-RFLP provides a rapid and reliable technique to investigate the diversity of the predominant vaginal microbiota and allows differentiation of the flora of BV and healthy women. As such, T-RFLP may be helpful both in the diagnosis of BV from vaginal fluids and in a better understanding of the bacterial succession involved in the aetiology of BV.


Assuntos
Bactérias/classificação , Técnicas Bacteriológicas/métodos , Impressões Digitais de DNA/métodos , Polimorfismo de Fragmento de Restrição , Vagina/microbiologia , Vaginose Bacteriana/microbiologia , Bactérias/isolamento & purificação , Biodiversidade , Análise por Conglomerados , DNA Bacteriano/análise , DNA Bacteriano/genética , DNA Ribossômico/análise , DNA Ribossômico/genética , Feminino , Humanos , RNA Ribossômico 16S/genética , Vaginose Bacteriana/diagnóstico
16.
Gastroenterology ; 132(4): 1309-19, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17408661

RESUMO

BACKGROUND & AIMS: The pathogenesis of Helicobacter pylori (Hp)-associated diseases depends on a specialized type IV secretion system. This type IV secretion system injects the cytotoxin-associated gene A (CagA) effector protein into target cells where CagA becomes phosphorylated on tyrosine residues by Src. Src then is inactivated rapidly, suggesting the presence of another host tyrosine kinase to ensure constant CagA phosphorylation in sustained Hp infections. We aimed to identify this kinase. METHODS: By using the AGS gastric epithelial cell model, we performed a detailed functional characterization of Abl tyrosine kinase in signaling during Hp infections. RESULTS: We showed that Abl kinase is activated and a novel crucial mediator of Hp infections. First, Abl-specific inhibitors SKI-DV2-43 or STI571 (Gleevec, Novartis) and knockdown of c-Abl/Abl-related gene Arg by small hairpin and interfering RNAs efficiently inhibit CagA phosphorylation and cell scattering. Second, during infection, Abl is activated rapidly by autophosphorylation at Y-412. Third, both Abl and Src phosphorylated Y-899, Y-918, and Y-972 of CagA. Fourth, we found that the Abl substrate CrkII is phosphorylated at Y-221 in vivo. Fifth, overexpression of kinase-dead Abl (K290M) blocked Hp-induced actin cytoskeletal rearrangements. We further showed that sustained activity of Abl is required to maintain CagA in a phosphorylated state. Moreover, phosphorylated CagA forms a physical complex with Abl and activated CrkII in vivo. CONCLUSIONS: We propose a model in which Hp has evolved a mechanism to use at least 2 tyrosine kinases, Abl and Src, for CagA phosphorylation and subsequent actin-cytoskeletal rearrangements leading to cell scattering and elongation.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Mucosa Gástrica/metabolismo , Regulação da Expressão Gênica , Infecções por Helicobacter/metabolismo , Helicobacter pylori/metabolismo , Proteínas Tirosina Quinases/genética , RNA Bacteriano/genética , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Benzamidas , Linhagem Celular , Epitélio/metabolismo , Epitélio/microbiologia , Epitélio/patologia , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Infecções por Helicobacter/genética , Infecções por Helicobacter/patologia , Humanos , Mesilato de Imatinib , Immunoblotting , Imunoprecipitação , Fatores Hospedeiros de Integração/genética , Microscopia de Fluorescência , Fosforilação , Piperazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Pirimidinas/farmacologia , Quinases da Família src/genética , Quinases da Família src/metabolismo
17.
Immunology ; 121(1): 71-81, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17425601

RESUMO

Respiratory syncytial virus (RSV) is the major causative agent of severe lower respiratory tract disease and death in infants worldwide. The epithelial cells of the airways are the target cells for RSV infection and the site of the majority of the inflammation associated with the disease. However, despite five decades of intensive RSV research there exist neither an effective active vaccine nor a promising antiviral and anti-inflammatory therapy. Recently, peroxisome proliferator-activated receptor-gamma (PPAR-gamma), a member of the nuclear hormone receptor superfamily, has been shown to possess anti-inflammatory properties. Therefore, we hypothesized whether the detrimental increase of intercellular adhesion molecule-1 (ICAM-1) on RSV-infected lung epithelial cells (A549 and primary normal human bronchial epithelial cells (NHBE)) might be modulated by natural and synthetic PPAR-gamma agonists (15d-PGJ2, ciglitazone, troglitazone, Fmoc-Leu). Our data show that all PPAR-gamma agonists under study significantly down-regulated the RSV-induced expression of ICAM-1 on A549- and NHBE cells in a dose-dependent manner resulting in a reduced beta2 integrin-mediated adhesion of monocytic effector cells (U937) to RSV-infected A549 cell monolayers. In contrast, the PPAR-alpha agonist bezafibrate had no impact on the RSV-induced ICAM-1 expression. The reduced ICAM-1 expression was associated with a diminished ICAM-1 mRNA level and binding activity of nuclear factor-kappaB (p65/p50) in A549 cells. These findings suggest that PPARgamma agonists have beneficial effects in the suppression of the inflammatory response during RSV infection and therefore might have clinical efficacy in the course of severe RSV-infection.


Assuntos
Molécula 1 de Adesão Intercelular/metabolismo , Pulmão/metabolismo , PPAR gama/agonistas , Infecções por Vírus Respiratório Sincicial/metabolismo , Aminoácidos/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Cromanos/farmacologia , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Células Epiteliais/metabolismo , Fluorenos/farmacologia , Humanos , NF-kappa B/metabolismo , PPAR gama/metabolismo , Prostaglandina D2/análogos & derivados , Prostaglandina D2/farmacologia , RNA Mensageiro/genética , Mucosa Respiratória/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Tiazolidinedionas/farmacologia , Troglitazona , Células U937
18.
FEMS Immunol Med Microbiol ; 50(2): 190-205, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17428306

RESUMO

The Helicobacter pylori CagA protein induces profound morphological changes in the host cytoskeleton and cell scattering, but the signalling involved is poorly understood. Pseudomonas aeruginosa also affects host actin cytoskeleton in a variety of ways by injecting the ExoS and ExoT toxins which encode N-terminal GTPase activating protein and C-terminal ADP-ribosyltransferase (ADPRT) activities. In this study we developed a novel coinfection assay to gain new insights into CagA effector protein functions. We found that P. aeruginosa injecting either ExoT or ExoS efficiently prevented the H. pylori-induced scattering phenotype. Both the Rho-GAP and the ADPRT domains of ExoS were needed to block the H. pylori-induced actin cytoskeletal rearrangements, whereas either domain of ExoT was sufficient for this activity. This strategy revealed common pathways subverted by different pathogens, and aided in the definition of signalling cascades that control the CagA-mediated cell scattering and elongation. We identified Crk adapter proteins, Rac1 and H-Ras, but not RhoA or Cdc42, which are the ExoS and/or ExoT targets, as crucial components of the CagA-induced phenotype. In addition, we show that ADP-ribosylation of CrkII by ExoT blocks phosphorylation of CrkII at Y-221, which is also important for the CagA-induced signalling.


Assuntos
Actinas/metabolismo , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Citoesqueleto/metabolismo , Helicobacter pylori/fisiologia , Proteínas Proto-Oncogênicas c-crk/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteínas ras/metabolismo , ADP Ribose Transferases/fisiologia , Toxinas Bacterianas , Linhagem Celular , Células Epiteliais/citologia , Células Epiteliais/microbiologia , Proteínas Ativadoras de GTPase/fisiologia , Humanos , Fosforilação , Pseudomonas aeruginosa/fisiologia , Transdução de Sinais
20.
Virology ; 350(2): 335-46, 2006 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-16616290

RESUMO

We have previously shown that peroxisome proliferator-activated receptor-gamma (PPARgamma) agonists inhibited the inflammatory response of RSV-infected human lung epithelial cells. In this study, we supply evidence that specific PPARgamma agonists (15d-PGJ2, ciglitazone, troglitazone, Fmoc-Leu) efficiently blocked the RSV-induced cytotoxicity and development of syncytia in tissue culture (A549, HEp-2). All PPARgamma agonists under study markedly inhibited the cell surface expression of the viral G and F protein on RSV-infected A549 cells. This was paralleled by a reduced cellular amount of N protein-encoding mRNA determined by real-time RT-PCR. Concomitantly, a reduced release of infectious progeny virus into the cell supernatants of human lung epithelial cells (A549, normal human bronchial epithelial cells (NHBE)) was observed. Similar results were obtained regardless whether PPARgamma agonists were added prior to RSV infection or thereafter, suggesting that the agonists inhibited viral gene expression and not the primary adhesion or fusion process.


Assuntos
Pulmão/virologia , PPAR gama/agonistas , Prostaglandina D2/análogos & derivados , Mucosa Respiratória/virologia , Vírus Sinciciais Respiratórios/fisiologia , Replicação Viral/efeitos dos fármacos , Cromanos/farmacologia , Humanos , Prostaglandina D2/farmacologia , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Tiazolidinedionas/farmacologia , Troglitazona , Replicação Viral/fisiologia
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