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[PMID]:28845032
[Au] Autor:Sumitomo T
[Ad] Endereço:Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry.
[Ti] Título:Streptococcus pyogenes translocates across an epithelial barrier.
[So] Source:Nihon Saikingaku Zasshi;72(3):213-218, 2017.
[Is] ISSN:1882-4110
[Cp] País de publicação:Japan
[La] Idioma:jpn
[Ab] Resumo:Streptococcus pyogenes is a ß-hemolytic organism responsible for a wide variety of human diseases that commonly occur as self-limiting purulent diseases of the pharynx and skin. Although the occurrence of invasive infections by S. pyogenes is rare, mortality rates remain high even with progressive medical therapy. As a prerequisite for causing the severe invasive disease, S. pyogenes must invade underlying sterile tissues by translocating across the epithelial barrier. In this study, streptolysin S and SpeB were identified as the novel factors that facilitate bacterial translocation via degradation of intercellular junctions. Furthermore, we found that S. pyogenes exploits host plasminogen for acceleration of bacterial invasion into deeper tissues via tricellular tight junctions. Here, I would like to show our study on bacterial translocation across the epithelial barrier through paracellular route.
[Mh] Termos MeSH primário: Translocação Bacteriana
Epitélio/microbiologia
Infecções Estreptocócicas/microbiologia
Streptococcus pyogenes/fisiologia
Streptococcus pyogenes/patogenicidade
[Mh] Termos MeSH secundário: Proteínas de Bactérias/fisiologia
Translocação Bacteriana/genética
Células Epiteliais/microbiologia
Células Epiteliais/fisiologia
Epitélio/fisiologia
Exotoxinas/fisiologia
Seres Humanos
Junções Intercelulares/microbiologia
Junções Intercelulares/fisiologia
Plasminogênio/metabolismo
Streptococcus pyogenes/genética
Estreptolisinas/fisiologia
Junções Íntimas/microbiologia
Junções Íntimas/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Exotoxins); 0 (Streptolysins); 0 (erythrogenic toxin); 0 (streptolysin S); 9001-91-6 (Plasminogen)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171015
[Lr] Data última revisão:
171015
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170829
[St] Status:MEDLINE
[do] DOI:10.3412/jsb.72.213


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[PMID]:28630064
[Au] Autor:Fang R; Wu R; Du H; Jin M; Liu Y; Lei G; Jiang B; Lei Z; Peng Y; Nie K; Tsuchiya K
[Ad] Endereço:College of Animal Science and Technology, Southwest University, Chongqing, China.
[Ti] Título:Pneumolysin-Dependent Calpain Activation and Interleukin-1α Secretion in Macrophages Infected with Streptococcus pneumoniae.
[So] Source:Infect Immun;85(9), 2017 Sep.
[Is] ISSN:1098-5522
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Pneumolysin (PLY), a major virulence factor of , is a pore-forming cytolysin that modulates host innate responses contributing to host defense against and pathogenesis of pneumococcal infections. Interleukin-1α (IL-1α) has been shown to be involved in tissue damage in a pneumococcal pneumonia model; however, the mechanism by which this cytokine is produced during infection remains unclear. In this study, we examined the role of PLY in IL-1α production. Although the strains induced similar levels of pro-IL-1α expression, wild-type D39, but not a deletion mutant of the gene (Δ ), induced the secretion of mature IL-1α from host macrophages, suggesting that PLY is critical for the maturation and secretion of IL-1α during infection. Further experiments with calcium chelators and calpain inhibitors indicated that extracellular calcium ions and calpains (calcium-dependent proteases) facilitated the maturation and secretion of IL-1α from D39-infected macrophages. Moreover, we found that PLY plays a critical role in calcium influx and calpain activation, as elevated intracellular calcium levels and the degradation of the calpain substrate α-fodrin were detected in macrophages infected with D39 but not the Δ strain. These results suggested that PLY induces the influx of calcium in -infected macrophages, followed by calpain activation and subsequent IL-1α maturation and secretion.
[Mh] Termos MeSH primário: Calpaína/metabolismo
Interações Hospedeiro-Patógeno
Interleucina-1alfa/secreção
Macrófagos/imunologia
Macrófagos/microbiologia
Streptococcus pneumoniae/crescimento & desenvolvimento
Estreptolisinas/metabolismo
[Mh] Termos MeSH secundário: Animais
Proteínas de Bactérias/metabolismo
Células Cultivadas
Feminino
Camundongos Endogâmicos C57BL
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Interleukin-1alpha); 0 (Streptolysins); 0 (plY protein, Streptococcus pneumoniae); EC 3.4.22.- (Calpain)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170906
[Lr] Data última revisão:
170906
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170621
[St] Status:MEDLINE


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[PMID]:28566646
[Au] Autor:Zhao X; Zhou Y; Wang G; Shi D; Zha Y; Yi P; Wang J
[Ad] Endereço:Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University.
[Ti] Título:Morin Moderates the Biotoxicity of Pneumococcal Pneumolysin by Weakening the Oligomers' Formation.
[So] Source:Chem Pharm Bull (Tokyo);65(6):538-544, 2017.
[Is] ISSN:1347-5223
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:Streptococcus pneumoniae (pneumococcus) is an important causative agent of acute invasive and non-invasive infections. Pneumolysin is one of a considerable number of virulence traits produced by pneumococcus that exhibits a variety of biological activities, thus making it a target of small molecule drug development. In this study, we aimed to evaluate the effect of morin, a natural compound that has no antimicrobial activity against S. pneumonia, is a potent neutralizer of pneumolysin-mediated cytotoxicity and genotoxicity by impairing oligomer formation, and possesses the capability of mitigating tissue damage caused by pneumococcus. These findings indicate that morin could be a potent candidate for a novel therapeutic or auxiliary substance to treat infections for which there are inadequate vaccines and that are resistant to traditional antibiotics.
[Mh] Termos MeSH primário: Biopolímeros/metabolismo
Flavonoides/farmacologia
Streptococcus pneumoniae/metabolismo
Estreptolisinas/toxicidade
[Mh] Termos MeSH secundário: Células A549
Animais
Proteínas de Bactérias/toxicidade
Feminino
Hemólise/efeitos dos fármacos
Seres Humanos
Camundongos
Camundongos Endogâmicos C57BL
Testes de Sensibilidade Microbiana
Streptococcus pneumoniae/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Biopolymers); 0 (Flavonoids); 0 (Streptolysins); 0 (plY protein, Streptococcus pneumoniae); 8NFQ3F76WR (morin)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170705
[Lr] Data última revisão:
170705
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170602
[St] Status:MEDLINE
[do] DOI:10.1248/cpb.c16-00999


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[PMID]:28554544
[Au] Autor:Joseph J; Kent N; Bowen A; Hart J; Sheel M; Wardrop R; Abbs S; Bazely S; Rybak M
[Ad] Endereço:PathWest Laboratory Medicine, QE2 Medical Centre Redevelopment, Australia. Electronic address: john.joseph@health.wa.gov.au.
[Ti] Título:Immuno-nephelometric determination of group streptococcal anti-streptolysin O titres (ASOT) from dried blood spots: Method for validating a new assay.
[So] Source:J Immunol Methods;448:59-65, 2017 Sep.
[Is] ISSN:1872-7905
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:This study was designed to determine the sensitivity and reproducibility of recovering anti-streptolysin O titres (ASOT) from dried blood spot (DBS) samples, a methodologic subcomponent of the penicillin pharmacokinetic studies in children receiving secondary prophylaxis with intramuscular benzathine penicillin for acute rheumatic fever.
[Mh] Termos MeSH primário: Antiestreptolisina/sangue
Teste em Amostras de Sangue Seco
Testes Imunológicos/métodos
Febre Reumática/diagnóstico
Estreptolisinas/imunologia
[Mh] Termos MeSH secundário: Antibacterianos/administração & dosagem
Antibacterianos/farmacocinética
Proteínas de Bactérias/imunologia
Biomarcadores/sangue
Calibragem
Desenho de Equipamento
Estudos de Viabilidade
Seres Humanos
Testes Imunológicos/instrumentação
Testes Imunológicos/normas
Injeções Intramusculares
Nefelometria e Turbidimetria
Penicilina G Benzatina/administração & dosagem
Penicilina G Benzatina/farmacocinética
Valor Preditivo dos Testes
Padrões de Referência
Reprodutibilidade dos Testes
Febre Reumática/sangue
Febre Reumática/tratamento farmacológico
Febre Reumática/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; VALIDATION STUDIES
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Bacterial Proteins); 0 (Biomarkers); 0 (Streptolysins); 0 (streptolysin O); 9006-92-2 (Antistreptolysin); RIT82F58GK (Penicillin G Benzathine)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170918
[Lr] Data última revisão:
170918
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170531
[St] Status:MEDLINE


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[PMID]:28411150
[Au] Autor:Suryawanshi RD; Malik SVS; Jayarao B; Chaudhari SP; Savage E; Vergis J; Kurkure NV; Barbuddhe SB; Rawool DB
[Ad] Endereço:Division of Veterinary Public Health, ICAR-Indian Veterinary Research Institute, Izatnagar 243 122, India.
[Ti] Título:Comparative diagnostic efficacy of recombinant LLO and PI-PLC-based ELISAs for detection of listeriosis in animals.
[So] Source:J Microbiol Methods;137:40-45, 2017 Jun.
[Is] ISSN:1872-8359
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The present study for the first time evaluates the serodiagnostic efficacy of two recombinant antigens namely, listeriolysin O (rLLO) and phosphatidyl-inositol phospholipase C (rPI-PLC). Indirect ELISA with the above recombinant antigens was used on samples collected from bovines (n=106), goats (n=138) and pigs (n=92) having either a history of abortion, emaciation and/or apparently healthy animals. Isolation of Listeria was attempted from the blood samples using USDA-FSIS method. On screening of test sera by rLLO-based ELISA, antibodies against anti-listeriolysin O (ALLO) were observed in goats (22.46%), bovines (15.10%) and pigs (16.31%). As advocated, after adsorption of positive serum samples with streptolysin O (SLO), the seropositivity for ALLO was marginally reduced (p>0.05) in goats (21.73%) and bovines (10.38%), whereas, in pigs the reduction (5.43%) was significant (p<0.05). On the contrary, rPI-PLC-based ELISA revealed higher non-specific seropositivity for antilisterial antibodies in goats (45.65%), bovines (31.13%) and pigs (8.69%). Further, on comparing the seropositivity with isolation rate, of the 16 animals that were culturally-positive for L. monocytogenes, 15 showed ALLO positivity in unadsorbed as well as SLO-adsorbed sera by rLLO-based ELISA, however, rPI-PLC-based ELISA could detect seropositivity in only 5 animals. Moreover, rPI-PLC-based ELISA also showed seropositivity in those animals (7/30) that were culturally positive for other Listeria spp. In conclusion, rLLO can serve as a better antigen than rPI-PLC in ELISA for the serodiagnosis of listeriosis in animals; however, prior adsorption of test sera with SLO is required to avoid false positive results.
[Mh] Termos MeSH primário: Doenças dos Animais/microbiologia
Toxinas Bacterianas/análise
Ensaio de Imunoadsorção Enzimática/veterinária
Proteínas de Choque Térmico/análise
Proteínas Hemolisinas/análise
Listeriose/veterinária
Fosfoinositídeo Fosfolipase C/análise
[Mh] Termos MeSH secundário: Doenças dos Animais/sangue
Doenças dos Animais/diagnóstico
Animais
Anticorpos Antibacterianos/sangue
Antígenos de Bactérias/genética
Proteínas de Bactérias/sangue
Toxinas Bacterianas/genética
Toxinas Bacterianas/imunologia
Bovinos
Ensaio de Imunoadsorção Enzimática/métodos
Cabras
Proteínas de Choque Térmico/genética
Proteínas de Choque Térmico/imunologia
Proteínas Hemolisinas/genética
Proteínas Hemolisinas/imunologia
Listeria/enzimologia
Listeria/isolamento & purificação
Listeriose/sangue
Listeriose/diagnóstico
Listeriose/imunologia
Fosfoinositídeo Fosfolipase C/genética
Fosfoinositídeo Fosfolipase C/imunologia
Proteínas Recombinantes/genética
Proteínas Recombinantes/imunologia
Sensibilidade e Especificidade
Testes Sorológicos/métodos
Testes Sorológicos/veterinária
Estreptolisinas/sangue
Suínos
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Bacterial); 0 (Antigens, Bacterial); 0 (Bacterial Proteins); 0 (Bacterial Toxins); 0 (Heat-Shock Proteins); 0 (Hemolysin Proteins); 0 (Recombinant Proteins); 0 (Streptolysins); 0 (streptolysin O); 72270-41-8 (hlyA protein, Listeria monocytogenes); EC 3.1.4.11 (Phosphoinositide Phospholipase C)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170808
[Lr] Data última revisão:
170808
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170416
[St] Status:MEDLINE


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[PMID]:28385613
[Au] Autor:Zhao X; Zhou Y; Wang L; Li M; Shi D; Li D; Wang J
[Ad] Endereço:Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China. Postal code: 130062.
[Ti] Título:Shikonin alleviates the biotoxicity produced by pneumococcal pneumolysin.
[So] Source:Life Sci;177:1-7, 2017 May 15.
[Is] ISSN:1879-0631
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:AIMS: Streptococcus pneumoniae (S. pneumoniae) is a common pathogen that can cause severe infections in humans. Pneumolysin (PLY) is an important virulence trait of S. pneumoniae and has cytotoxicity, genotoxicity and pro-inflammatory activity; it is essential for the pathogenesis of S. pneumoniae pneumonia and is an anti-virulence target of small molecule drug development. The treatment options for this microbe were limit due to the ubiquitous antibiotic resistance; therefore, new drugs and treatment strategies are needed. METHODS: Shikonin was selected by drug screening based on haemolysis assays, and its mechanism of suppressing PLY toxicity was determined by oligomerization assay. Meanwhile, the in vitro cell viability assays and in vivo experiments were performed to explore the capability of shikonin to protect cells and tissue from S. pneumoniae-mediated damage. KEY FINDINGS: Shikonin was found to significantly decrease PLY-induced haemolytic activity, cytotoxicity and genotoxicity via lessening the formation of oligomers; moreover, the agent can reduce the mortality of mice caused by lethal pneumonia and mitigate the injury of target organs as well. SIGNIFICANCE: We suggest that shikonin could be a potent candidate for a novel therapeutic or auxiliary substance in the treatment of infections encountering insufficient vaccines and antimicrobial resistance to traditional antibiotics.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Naftoquinonas/farmacologia
Pneumonia Pneumocócica/tratamento farmacológico
Streptococcus pneumoniae/efeitos dos fármacos
Estreptolisinas/antagonistas & inibidores
[Mh] Termos MeSH secundário: Animais
Proteínas de Bactérias/antagonistas & inibidores
Sobrevivência Celular/efeitos dos fármacos
Desenho de Drogas
Feminino
Hemólise/efeitos dos fármacos
Seres Humanos
Camundongos
Camundongos Endogâmicos C57BL
Pneumonia Pneumocócica/microbiologia
Streptococcus pneumoniae/patogenicidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Bacterial Proteins); 0 (Naphthoquinones); 0 (Streptolysins); 0 (plY protein, Streptococcus pneumoniae); 3IK6592UBW (shikonin)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170629
[Lr] Data última revisão:
170629
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170408
[St] Status:MEDLINE


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[PMID]:28381239
[Au] Autor:Nayiga I; Okello E; Lwabi P; Ndeezi G
[Ad] Endereço:Department of Paediatrics & Child Health, College of health sciences, Makerere University, P.O Box 7072, Kampala, Uganda. nayigairene@yahoo.com.
[Ti] Título:Prevalence of group a streptococcus pharyngeal carriage and clinical manifestations in school children aged 5-15 yrs in Wakiso District, Uganda.
[So] Source:BMC Infect Dis;17(1):248, 2017 Apr 05.
[Is] ISSN:1471-2334
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Beta-hemolytic streptococci carrier rates in children living in low-income countries are high ranging from 10 to 50%. Although most of these children are asymptomatic, they are a reservoir and pose a risk of transmission. The aim of this study was to determine the prevalence of group a streptococcus pharyngeal carriage and clinical manifestations in school going children in Wakiso district, Uganda. METHODS: A cross sectional study targeting children age 5-15 years in primary schools in one sub-county of Wakiso district was carried out. Three hundred and sixty-six children from five primary schools were enrolled and evaluated for group a streptococcus (GAS) carriage. A semi-structured questionnaire was used to collect data that included social demographics, school environment and clinical findings. For every enrolled child a throat swab was taken and cultured for GAS and blood was drawn for anti-streptolysin-O titres. Analysis of data was done using STATA. RESULTS: The prevalence of GAS carriage was 16%. The children with GAS positive cultures were mainly females. The factor associated with GAS carriage was the school location, with peri-urban schools more likely to have children with GAS compared to rural schools; AOR 2.48 (95% CI: 1.01 - 6.11), P = 0.049. There was no significant difference between the characteristic of children with GAS positive verses GAS negative throat swab cultures. CONCLUSION: There is a high prevalence of GAS pharyngeal carriage among children aged 5-15 years attending primary schools in Wakiso District, Uganda.
[Mh] Termos MeSH primário: Faringe/microbiologia
Infecções Estreptocócicas/epidemiologia
Streptococcus pyogenes
[Mh] Termos MeSH secundário: Adolescente
Proteínas de Bactérias
Portador Sadio/epidemiologia
Criança
Estudos Transversais
Feminino
Seres Humanos
Masculino
Pobreza
Prevalência
População Rural
Instituições Acadêmicas
Infecções Estreptocócicas/fisiopatologia
Estreptolisinas
Inquéritos e Questionários
Uganda/epidemiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Streptolysins); 0 (streptolysin O)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170628
[Lr] Data última revisão:
170628
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170407
[St] Status:MEDLINE
[do] DOI:10.1186/s12879-017-2353-5


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[PMID]:28232188
[Au] Autor:Kwon IS; Kim J; Rhee DK; Kim BO; Pyo S
[Ad] Endereço:School of Pharmacy, Sungkyunkwan University, Suwon, Gyunggi-do, 16419, Republic of Korea.
[Ti] Título:Pneumolysin induces cellular senescence by increasing ROS production and activation of MAPK/NF-κB signal pathway in glial cells.
[So] Source:Toxicon;129:100-112, 2017 Apr.
[Is] ISSN:1879-3150
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Senescence is an irreversible proliferation arrest that is induced by various stress stimuli including genotoxin. Pneumolysin (PLY) is a pathogenicity factor unique to Streptococcus pneumoniae that is important in pneumococcal-induced diseases such as otitis media, meningitis and pneumonia. However, the cell fate response to the toxin is mechanistically unclear. We investigated the effect of PLY on cellular senescence in BV-2 microglial cells. Exposure to PLY resulted in changes in the expression of phospho-p53, p21, p16, pRb and CDK2 and increased the number of senescence associated ß-gal positive cells. PLY-treatment also increased PAI-1 expression and cell proliferation arrest in concentration- and time-dependent manners. PLY induced NF-κB activation and phosphorylation of SIRT-1, ERK1/2, JNK, and p38 MAPK. In addition, PLY increased the production of reactive oxygen species. Overall, the results suggest that PLY regulates microglial cellular senescence by enhancing production of reactive oxygen species, activation of MAPK and NF-κB, and phosphorylation of SIRT-1.
[Mh] Termos MeSH primário: Senescência Celular/efeitos dos fármacos
Sistema de Sinalização das MAP Quinases
Proteínas Quinases Ativadas por Mitógeno/metabolismo
NF-kappa B/metabolismo
Espécies Reativas de Oxigênio/metabolismo
Estreptolisinas/farmacologia
[Mh] Termos MeSH secundário: Animais
Proteínas de Bactérias/farmacologia
Linhagem Celular
Proliferação Celular/efeitos dos fármacos
Sobrevivência Celular/efeitos dos fármacos
Seres Humanos
Camundongos
Proteínas Quinases Ativadas por Mitógeno/genética
NF-kappa B/genética
Neuroglia/efeitos dos fármacos
Neuroglia/metabolismo
Fosforilação
Ratos
Transdução de Sinais
Sirtuína 1/genética
Sirtuína 1/metabolismo
Streptococcus pneumoniae
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (NF-kappa B); 0 (Reactive Oxygen Species); 0 (Streptolysins); 0 (plY protein, Streptococcus pneumoniae); EC 2.7.11.24 (Mitogen-Activated Protein Kinases); EC 3.5.1.- (Sirtuin 1)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170225
[St] Status:MEDLINE


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[PMID]:28098781
[Au] Autor:Maurer J; Hupp S; Bischoff C; Foertsch C; Mitchell TJ; Chakraborty T; Iliev AI
[Ad] Endereço:DFG Membrane/Cytoskeleton Interaction Group, Institute of Pharmacology and Toxicology & Rudolf Virchow Center for Experimental Biomedical Science, University of Würzburg, Versbacherstr. 9, 97078 Würzburg, Germany. jana_maurer@t-online.de.
[Ti] Título:Distinct Neurotoxicity Profile of Listeriolysin O from Listeria monocytogenes.
[So] Source:Toxins (Basel);9(1), 2017 Jan 13.
[Is] ISSN:2072-6651
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Cholesterol-dependent cytolysins (CDCs) are protein toxins that originate from Gram-positive bacteria and contribute substantially to their pathogenicity. CDCs bind membrane cholesterol and build prepores and lytic pores. Some effects of the toxins are observed in non-lytic concentrations. Two pathogens, and , cause fatal bacterial meningitis, and both produce toxins of the CDC family-pneumolysin and listeriolysin O, respectively. It has been demonstrated that pneumolysin produces dendritic varicosities (dendrite swellings) and dendritic spine collapse in the mouse neocortex, followed by synaptic loss and astrocyte cell shape remodeling without elevated cell death. We utilized primary glial cultures and acute mouse brain slices to examine the neuropathological effects of listeriolysin O and to compare it to pneumolysin with identical hemolytic activity. In cultures, listeriolysin O permeabilized cells slower than pneumolysin did but still initiated non-lytic astrocytic cell shape changes, just as pneumolysin did. In an acute brain slice culture system, listeriolysin O produced dendritic varicosities in an NMDA-dependent manner but failed to cause dendritic spine collapse and cortical astrocyte reorganization. Thus, listeriolysin O demonstrated slower cell permeabilization and milder glial cell remodeling ability than did pneumolysin and lacked dendritic spine collapse capacity but exhibited equivalent dendritic pathology.
[Mh] Termos MeSH primário: Astrócitos/efeitos dos fármacos
Toxinas Bacterianas/toxicidade
Encéfalo/efeitos dos fármacos
Espinhas Dendríticas/efeitos dos fármacos
Proteínas de Choque Térmico/toxicidade
Proteínas Hemolisinas/toxicidade
Listeria monocytogenes/metabolismo
Neurotoxinas/toxicidade
[Mh] Termos MeSH secundário: Animais
Animais Recém-Nascidos
Astrócitos/patologia
Proteínas de Bactérias/genética
Proteínas de Bactérias/toxicidade
Toxinas Bacterianas/genética
Encéfalo/patologia
Permeabilidade da Membrana Celular/efeitos dos fármacos
Forma Celular/efeitos dos fármacos
Sobrevivência Celular/efeitos dos fármacos
Células Cultivadas
Espinhas Dendríticas/patologia
Proteínas de Choque Térmico/genética
Proteínas Hemolisinas/genética
Camundongos Endogâmicos C57BL
Neurotoxinas/genética
Cultura Primária de Células
Proteínas Recombinantes
Estreptolisinas/genética
Estreptolisinas/toxicidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Bacterial Toxins); 0 (Heat-Shock Proteins); 0 (Hemolysin Proteins); 0 (Neurotoxins); 0 (Recombinant Proteins); 0 (Streptolysins); 0 (plY protein, Streptococcus pneumoniae); 72270-41-8 (hlyA protein, Listeria monocytogenes)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171110
[Lr] Data última revisão:
171110
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170119
[St] Status:MEDLINE


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[PMID]:28081446
[Au] Autor:Zafar MA; Wang Y; Hamaguchi S; Weiser JN
[Ad] Endereço:Department of Microbiology, New York University, New York, NY 10016, USA.
[Ti] Título:Host-to-Host Transmission of Streptococcus pneumoniae Is Driven by Its Inflammatory Toxin, Pneumolysin.
[So] Source:Cell Host Microbe;21(1):73-83, 2017 Jan 11.
[Is] ISSN:1934-6069
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Host-to-host transmission is a critical step for infection. Here we studied transmission of the opportunistic pathogen Streptococcus pneumoniae in an infant mouse model. Transmission from nasally colonized pups required high levels of bacterial shedding in nasal secretions and was temporally correlated with, and dependent upon, the acute inflammatory response. Pneumolysin, a pore-forming cytotoxin and major virulence determinant, was both necessary and sufficient to promote inflammation, which increased shedding and allowed for intralitter transmission. Direct contact between pups was not required for transmission indicating the importance of an environmental reservoir. An additional in vivo effect of pneumolysin was to enhance bacterial survival outside of the host. Our findings provide experimental evidence of a microbial strategy for transit to new hosts and explain why an organism expresses a toxin that damages the host upon which it depends.
[Mh] Termos MeSH primário: Inflamação/imunologia
Infecções Pneumocócicas/transmissão
Sistema Respiratório/microbiologia
Streptococcus pneumoniae/patogenicidade
Estreptolisinas/metabolismo
[Mh] Termos MeSH secundário: Animais
Carga Bacteriana
Proteínas de Bactérias/metabolismo
Modelos Animais de Doenças
Camundongos
Camundongos Endogâmicos C57BL
Camundongos Knockout
Infecções Pneumocócicas/microbiologia
Sistema Respiratório/imunologia
Sistema Respiratório/patologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Streptolysins); 0 (plY protein, Streptococcus pneumoniae)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170919
[Lr] Data última revisão:
170919
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170113
[St] Status:MEDLINE



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