Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 71
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Artigo em Inglês | MEDLINE | ID: mdl-32169530

RESUMO

BACKGROUND: Nontyphoid Salmonella and Shigella can cause gastroenteritis in humans. Ceftriaxone (CRO) has been used to treat their infection, however, development of CRO resistance are often associated with plasmid-mediated blaCMY. Here, we investigated the presence of plasmid-mediated ISEcp-1 tnpA-blaCMY-2-blc-sugE and the role of these genes in regulation of CRO susceptibility in different hosts. METHODS: 194 strains of Salmonella serovars and Shigella were tested for CRO susceptibility. Non-susceptibility strains were examined for plasmid-mediated ISEcp-1 tnpA-blaCMY-2-blc-sugE by PCR amplification, Southern blot, and DNA sequencing. The plasmid profiles were determined by HindIII-digested restriction fragment length polymorphism (RFLP). Four recombinant plasmids with different genes from ISEcp-1 tnpA-blaCMY-2-blc-sugE were constructed and then were transferred into Escherichia coli and different Salmonella serovars to evaluate the CRO susceptibility. RESULTS: Among 20 CRO-nonsusceptible isolates of Salmonella Choleraesuis (5), S. Typhimurium (4), S. Mons (1), S. Stanley (2) and Shigella sonnei (8) with plasmid-mediated blaCMY-2, 19 isolates carried the ISEcp-1 tnpA-blaCMY-2-blc-sugE and only one isolate with tnpA-blaCMY-2. Transformation of these plasmids into E. coli pir116 produced multidrug resistance. Furthermore, PCR-RFLP analysis determined 5 different plasmid profiles and identical RFLP pattern between S. Typhimurium and S. sonnei. Transformation of the recombinant plasmids into E. coli and different Salmonella serovars resulted in phenotypes ranging from susceptible to resistant (especially inducible resistance) to CRO that were dependent on the genes, and host. CONCLUSION: The CRO susceptibility associated with the ISEcp-1 tnpA-blaCMY-2-blc-sugE element is regulated positively by ISEcp-1 tnpA and SugE and negatively regulated by Blc and unknown species-dependent host factor(s).

2.
Pol J Microbiol ; 68(4): 439-447, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31880888

RESUMO

Salmonella infection is most common in patients with infected aortic aneurysm, especially in Asia. When the aortic wall is heavily atherosclerotic, the intima is vulnerable to invasion by Salmonella, leading to the development of infected aortic aneurysm. By using THP-1 macrophage-derived foam cells to mimic atherosclerosis, we investigated the role of three Salmonella enterica serotypes - Typhimurium, Enteritidis, and Choleraesuis - in foam cell autophagy and inflammasome formation. Herein, we provide possible pathogenesis of Salmonella-associated infected aortic aneurysms. Three S. enterica serotypes with or without virulence plasmid were studied. Through Western blotting, we investigated cell autophagy induction and inflammasome formation in Salmonella-infected THP-1 macrophage-derived foam cells, detected CD36 expression after Salmonella infection through flow cytometry, and measured interleukin (IL)-1ß, IL-12, and interferon (IFN)-α levels through enzyme-linked immunosorbent assay. At 0.5 h after infection, plasmid-bearing S. Enteritidis OU7130 induced the highest foam cell autophagy - significantly higher than that induced by plasmid-less OU7067. However, plasmid-bearing S. Choleraesuis induced less foam cell autophagy than did its plasmid-less strain. In foam cells, plasmid-less Salmonella infection (particularly S. Choleraesuis OU7266 infection) led to higher CD36 expression than did plasmid-bearing strains infection. OU7130 and OU7266 infection induced the highest IL-1ß secretion. OU7067-infected foam cells secreted the highest IL-12p35 level. Plasmid-bearing S. Typhimurium OU5045 induced a higher IFN-α level than did other Salmonella serotypes. Salmonella serotypes are correlated with foam cell autophagy and IL-1ß secretion. Salmonella may affect the course of foam cells formation, or even aortic aneurysm, through autophagy.Salmonella infection is most common in patients with infected aortic aneurysm, especially in Asia. When the aortic wall is heavily atherosclerotic, the intima is vulnerable to invasion by Salmonella, leading to the development of infected aortic aneurysm. By using THP-1 macrophage-derived foam cells to mimic atherosclerosis, we investigated the role of three Salmonella enterica serotypes ­ Typhimurium, Enteritidis, and Choleraesuis ­ in foam cell autophagy and inflammasome formation. Herein, we provide possible pathogenesis of Salmonella-associated infected aortic aneurysms. Three S. enterica serotypes with or without virulence plasmid were studied. Through Western blotting, we investigated cell autophagy induction and inflammasome formation in Salmonella-infected THP-1 macrophage-derived foam cells, detected CD36 expression after Salmonella infection through flow cytometry, and measured interleukin (IL)-1ß, IL-12, and interferon (IFN)-α levels through enzyme-linked immunosorbent assay. At 0.5 h after infection, plasmid-bearing S. Enteritidis OU7130 induced the highest foam cell autophagy ­ significantly higher than that induced by plasmid-less OU7067. However, plasmid-bearing S. Choleraesuis induced less foam cell autophagy than did its plasmid-less strain. In foam cells, plasmid-less Salmonella infection (particularly S. Choleraesuis OU7266 infection) led to higher CD36 expression than did plasmid-bearing strains infection. OU7130 and OU7266 infection induced the highest IL-1ß secretion. OU7067-infected foam cells secreted the highest IL-12p35 level. Plasmid-bearing S. Typhimurium OU5045 induced a higher IFN-α level than did other Salmonella serotypes. Salmonella serotypes are correlated with foam cell autophagy and IL-1ß secretion. Salmonella may affect the course of foam cells formation, or even aortic aneurysm, through autophagy.


Assuntos
Aneurisma Aórtico/microbiologia , Infecções por Salmonella/microbiologia , Salmonella typhimurium/patogenicidade , Animais , Aneurisma Aórtico/genética , Aneurisma Aórtico/imunologia , Linhagem Celular , Humanos , Interferon-alfa/genética , Interferon-alfa/imunologia , Interleucina-12/genética , Interleucina-12/imunologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Antígeno Ki-1/genética , Antígeno Ki-1/imunologia , Macrófagos/imunologia , Macrófagos/microbiologia , Monócitos/imunologia , Monócitos/microbiologia , Plasmídeos/genética , Plasmídeos/metabolismo , Infecções por Salmonella/genética , Infecções por Salmonella/imunologia , Salmonella typhimurium/genética , Salmonella typhimurium/fisiologia , Sorogrupo , Virulência
3.
Artigo em Inglês | MEDLINE | ID: mdl-31300124

RESUMO

S. Choleraesuis (Choleraesuis) and S. Typhimurium (Typhimurium) cause salmonellosis in pigs and humans. The effects of vaccine strains pSV-less Typhimurium OU5048 and Choleraesuis OU7266 and SPI-2-mutant Choleraesuis SC2284 on the immune responses of pigs against Typhimurium, Choleraesuis, and S. Enteritidis (Enteritidis) with or without the virulence plasmid (pSV) were determined. After oral vaccination of three vaccine groups and challenge with Choleraesuis CN36, the level of Salmonella-specific IgG in sera and the bactericidal effects and superoxide generation of peripheral blood mononuclear cells (PBMCs) and polymorphonuclear leukocytes (PMNs) against the above strains were determined using ELISA and NBT assay, respectively. Among three vaccine strains tested, OU7266 stimulated the highest Salmonella-specific IgG levels. Complement inactivation increased IgG concentration, while E. coli absorption reduced IgG levels. The pSV-containing strains were less resistant to serum killing than the pSV-less strains, and Enteritidis exhibited the lowest resistance to serum killing. Serovars tested, vaccine strains, and timeline periods postvaccination and challenge were important factors affecting superoxide production. The two Choleraesuis vaccine strains stimulated greater levels of superoxide from PMNs and PBMCs than the Typhimurium strains. The PMNs and PBMCs in challenged and vaccinated pigs reduced more superoxide than those in challenged hosts. In vaccinated hosts, pSV-less Salmonella strains triggered lower levels of PMN/PBMC-generated superoxide upon challenge than strains with pSV against Enteritidis and Choleraesuis. Overall, Choleraesuis OU7266 may be better than the other vaccine strains in generating the greatest IgG levels, serum bactericidal activity and superoxide levels. The pSV likely influences the immune responses.


Assuntos
Imunoglobulina G/sangue , Salmonelose Animal/prevenção & controle , Vacinas contra Salmonella/uso terapêutico , Doenças dos Suínos/prevenção & controle , Animais , Anticorpos Antibacterianos/sangue , Proteínas do Sistema Complemento/imunologia , Escherichia coli/imunologia , Escherichia coli/metabolismo , Feminino , Leucócitos Mononucleares/imunologia , Neutrófilos/imunologia , Espécies Reativas de Oxigênio/imunologia , Salmonella , Salmonelose Animal/imunologia , Vacinas contra Salmonella/imunologia , Salmonella typhimurium , Ensaios de Anticorpos Bactericidas Séricos , Suínos , Vacinação/veterinária , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/uso terapêutico
4.
Artigo em Inglês | MEDLINE | ID: mdl-30961803

RESUMO

Salmonella Typhimurium and S. Stanley are the most prevalent serogroup B serovars to infect humans in Taiwan. The aim was to determine possible factors to influence the prevalence between S. Typhimurium and S. Stanley. Genotypes were determined by pulsed field gel electrophoresis (PFGE) analysis and the intracellular survival, phagocytosis, reactive oxygen species (ROS) production of human monocyte THP-1 cell and tumor necrosis factor-α(TNF-α), interleukin-6 (IL-6), and IL-1ßexpression in peripheral blood CD14+ cells after infection were analyzed. 182 S. Stanley was clonal disseminated with main pulsotypes 2 from 2004 to 2007. Overall S. Typhimurium evolved more genotypes, while S. Stanley conserved in genotypes. Human blood CD14+ monocytes expressed TNF-α, IL-6 and IL-1ß differently among serovars and bacterial conditions (live vs. killed). Live S. Stanley and S. Typhimurium suppressed the TNF-α and IL-6 expression compared to killed bacteria. However, live S. Typhimurium stimulated more IL-1ß expression than the killed bacteria, but S. Stanley expressed similar IL-1ß levels in both conditions. Furthermore, S. Stanley and S. Typhimurium differed in intracellular survival in the THP-1 cells, an early decrease for S. Stanley, not for S. Typhimurium. Additionally, higher reactive oxygen species (ROS) production in THP-1 cells was found agsinst S. Stanley infection, not found in S. Typhimurium. However, some isolates of S. Stanley could recover from early loss to become more in the monocytes than S. Typhimurium. Difference in phagocytized number, intracellular survival, ROS production and IL-1ß expression may contribute to prevalence different between two serovars.


Assuntos
Monócitos/imunologia , Fagocitose/imunologia , Infecções por Salmonella/imunologia , Salmonella typhimurium/imunologia , beta-Lactamases/genética , Linhagem Celular Tumoral , Eletroforese em Gel de Campo Pulsado , Humanos , Interleucina-1beta/biossíntese , Interleucina-6/biossíntese , Espécies Reativas de Oxigênio/metabolismo , Infecções por Salmonella/epidemiologia , Infecções por Salmonella/microbiologia , Salmonella typhimurium/genética , Salmonella typhimurium/isolamento & purificação , Células THP-1 , Taiwan , Fator de Necrose Tumoral alfa/biossíntese
5.
Microbiologyopen ; 8(8): e00800, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30680961

RESUMO

Hemodialysis patients are particularly vulnerable to Staphylococcus aureus infection, with the vascular access serving as the site of entry for this formidable pathogen. Patients with arteriovenous grafts (AVGs) and tunneled-cuffed catheters (TCCs) are at elevated risk of S. aureus infection. In this study, we investigated the correlation between the clinical characteristics of S. aureus vascular access infection (VAI), molecular profiles, and the biofilm formation abilities of clinical isolates of S. aureus. We collected samples of methicillin-resistant S. aureus (MRSA), methicillin-sensitive S. aureus (MSSA), and methicillin-sensitive S. argenteus (MSSAg) from patients with S. aureus VAI and patients with other infections. The molecular profiles of the clinical isolates were determined using disk diffusion testing and molecular typing. The biofilm formation ability was determined by microtiter plate assay. In total, 63 S. aureus and 10 S. argenteus isolates were identified: 40 MRSA, 23 MSSA, and ten MSSAg. MRSA was highly prevalent (77.8%) in TCC isolates and was multidrug resistant. Of the 40 MRSA isolates, ST239-SCCmec III was the predominant clone. SCCmec type IV was the predominant type (35%) in isolates from AVGs, while SCCmec type III was prevalent in TCC infection and showed significantly higher biofilm formation ability than types IV and V. In dialysis VAI by S. aureus, patients with TCC were more often infected with MRSA than patients with AVG, and MRSA in TCC-VAI was predominantly SCCmec type III, which had the strongest drug resistance and biofilm formation ability.


Assuntos
Infecções Relacionadas a Cateter/microbiologia , Diálise Renal/efeitos adversos , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/isolamento & purificação , Idoso , Biofilmes/crescimento & desenvolvimento , Testes Diagnósticos de Rotina , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana Múltipla , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Tipagem Molecular , Staphylococcus , Staphylococcus aureus/classificação , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Taiwan , Centros de Atenção Terciária
6.
Microb Pathog ; 128: 69-74, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30583022

RESUMO

Salmonella is a common foodborne and zoonotic pathogen. Only a few serovars carry a virulence plasmid (pSV), which enhances the pathogenicity of the host. Here, we investigated the pathogenicity roles of the pSVs among wild-type, plasmid-less, and complemented S. Typhimurium, S. Enteritidis S. Choleraesuis in invasion, phagocytosis, and intracellular bacterial survival in human THP-1 cells and cell death patterns by flow cytometry and difference in cell death patterns between pig and human S. Choleraesuis isolates with large pSCVs. Virulence plasmid (pSTV) led to slightly increasing cellular apoptosis for S. Typhimurium; virulence plasmid (pSEV) enhanced apoptosis and necrosis significantly for S. Enteritidis; and pSCV reduced apoptosis significantly for S. Choleraesuis. After complementation, pSTV increased the intracellular survival of pSCV-less Choleraesuis and the cytotoxicity against human THP-1 cells. Using the Cytochalasin D to differentiate the invasion of S. Choleraaesuis and phagocytosis of THP-1 cells determined that pSCV were responsible for invasion and phagocytosis at 0 h and inhibited intracellular replication in THP-1 cells, and pSTV were responsible for invasion and increased intracellular survival for S. Choleraesuis in THP-1 cells. The human isolates with large pSCV induced more cellular apoptosis and necrosis than the pig isolates. In conclusion, human S. Choleraesuis isolates carrying large pSCVs were more adapted to human THP-1 cells for more cell death than pig isolates with large pSCV. The role of pSVs in invasion, phagocytosis, intracellular survival and apoptosis differed among hosted serovars.


Assuntos
Morte Celular , Interações Hospedeiro-Patógeno , Plasmídeos/genética , Salmonella enterica/genética , Salmonella enteritidis/genética , Salmonella typhimurium/genética , Fatores de Virulência/genética , Animais , Apoptose , Citocalasina D/farmacologia , Replicação do DNA , Genes Bacterianos , Humanos , Camundongos , Viabilidade Microbiana , Necrose , Células RAW 264.7 , Salmonelose Animal/microbiologia , Salmonella enterica/patogenicidade , Salmonella enteritidis/patogenicidade , Salmonella typhimurium/patogenicidade , Sorogrupo , Suínos , Células THP-1 , Virulência
7.
Oncol Lett ; 15(4): 5915-5923, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29552223

RESUMO

Natural compounds have been candidates for anticancer medicine over the last 20 years. During the process of isolating seed oil from Calophyllum inophyllum L., yellow and green pigments containing multiple compounds with an aromatic structure were identified. High-performance liquid chromatography and nuclear magnetic resonance analysis of these pigments revealed that the compounds present were identical, but the concentration of the compounds was different. Treatment with the pigments was able to induce the death of DLD-1 human colon cancer cells and increase the percentage of the cells in the sub-G1 and sub-G2/M phases in a dose-dependent manner. Additionally, the pigments were able to exhibit cytotoxic activity on A549 and H1975 human non-small cell lung cancer (NSCLC) cell lines at 24 h, with half-maximal inhibitory concentrations (IC50) values of 0.1206 and 0.0676%, respectively for green pigments, and 0.0434 and 0.0501%, respectively for yellow pigments. Furthermore, a decrease in IC50 value was associated with an increase in the duration of treatment. However, a sharp decrease in IC50 value of the yellow pigment was observed for H1975 cells at 48 h and for A549 cells at 72 h compared with no change in IC50 value for the green pigment with time, suggesting that the pigments function and induce cell death differently in the two cell lines. An investigation was performed into the synergistic effect of the green pigment and gefitinib (Iressa®, ZD1839), which is a selective epidermal growth factor receptor-tyrosine kinase inhibitor to block growth factor-mediated cell proliferation. The combination of the green pigment and gefitinib resulted in an enhancement of the decrease in viability of A549 and H1975 cells compared with treatment with gefitinib alone, which suggested that treatment with the green pigments was able to enhance the sensitivity of NSCLC cells to gefitinib. In conclusion, these pigments may be considered for development as anti-colon cancer agents.

8.
Int J Mol Med ; 41(1): 541-547, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29115410

RESUMO

Arachidin-1 [trans-4-(3-methyl-1-butenyl)-3,5,3',4'-tetrahydroxystilbene] is a polyphenol produced by peanut kernels during germination. The aim of the present study was to investigate the mechanism underlying the anti-inflammatory effect of arachidin-1 in endothelial cells (ECs). The results of cell adhesion and western blotting assays demonstrated that arachidin-1 attenuated tumor necrosis factor (TNF)-α-induced monocyte/EC adhesion and intercellular adhesion molecule-1 (ICAM-1) expression. Arachidin-1 was demonstrated to exert its inhibitory effects by the attenuation of TNF-α-induced nuclear factor-κB (NF-κB) nuclear translocation and inhibitor of κB-α (IκBα) degradation. Furthermore, arachidin-1 upregulated nuclear factor-E2-related factor-2 (Nrf-2), a known mediator of phase II enzyme expression, and increased the transcriptional activity of antioxidant response element. Transfection of ECs with Nrf-2 siRNA blocked the inhibitory effect of arachidin-1 on ICAM-1 expression, NF-κB nuclear translocation and IκBα degradation. In addition, arachidin-1 induced the expression of the phase II enzymes thioredoxin-1, thioredoxin reductase-1, heme oxygenase-1, glutamyl-cysteine synthetase and glutathione S-transferase. Following arachidin-1 pretreatment, the H2O2-induced generation of reactive oxygen species was reduced. Therefore, the present results indicate that arachidin-1 suppresses TNF-α-induced inflammation in ECs through the upregulation of Nrf-2-related phase II enzyme expression.


Assuntos
Inflamação/tratamento farmacológico , Molécula 1 de Adesão Intercelular/genética , Fator 2 Relacionado a NF-E2/genética , Estilbenos/administração & dosagem , Fator de Necrose Tumoral alfa/genética , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Arachis/química , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio/toxicidade , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/patologia , Desintoxicação Metabólica Fase II/genética , Inibidor de NF-kappaB alfa/genética , NF-kappa B/genética , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio/metabolismo , Estilbenos/química , Transfecção
9.
J Vis Exp ; (113)2016 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-27500729

RESUMO

This protocol describes the development of a colloidal gold immunochromatographic test strip based on the sandwich format that can be used to differentiate the myoglobin (Mb) of cetaceans from that of seals and other animals. The strip provides rapid and on-the-spot screening for cetacean meat, thereby restraining its illegal trade and consumption. Two monoclonal antibodies (mAbs) with reactivity toward the Mb of cetaceans were developed. The amino acid sequences of Mb antigenic reactive regions from various animals were analyzed in order to design two synthetic peptides (a general peptide and a specific peptide) and thereafter raise the mAbs (subclass IgG1). The mAbs were selected from hybridomas screened by indirect ELISA, western blot and dot blot. CGF5H9 was specific to the Mbs of rabbits, dogs, pigs, cows, goats, and cetaceans while it showed weak to no affinity to the Mbs of chickens, tuna and seals. CSF1H13 can bind seals and cetaceans with strong affinity but showed no affinity to other animals. Cetacean samples from four families (Balaenopteridae, Delphinidae, Phocoenidae and Kogiidae) were used in this study, and the results indicated that these two mAbs have broad binding ability to Mbs from different cetaceans. These mAbs were applied on a sandwich-type colloidal gold immunochromatographic test strip. CGF5H9, which recognizes many species, was colloid gold-labeled and used as the detection antibody. CSF1H13, which was coated on the test zone, detected the presence of cetacean and seal Mbs. Muscle samples from tuna, chicken, seal, five species of terrestrial mammals and 15 species of cetaceans were tested in triplicate. All cetacean samples showed positive results and all the other samples showed negative results.


Assuntos
Anticorpos Monoclonais/química , Cetáceos , Cromatografia de Afinidade/métodos , Coloide de Ouro/química , Mioglobina/análise , Animais , Técnicas de Química Sintética , Sensibilidade e Especificidade , Especificidade da Espécie
10.
BMC Microbiol ; 16(1): 175, 2016 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-27484120

RESUMO

BACKGROUND: Streptococcus agalactiae (GBS) is a common pathogen to infect newborn, woman, the elderly, and immuno-compromised human and fish. 37 fish isolates and 554 human isolates of the GBS in 2007-2012 were investigated in serotypes, antibiotic susceptibility, genetic difference and pathogenicity to tilapia. RESULTS: PCR serotyping determined serotype Ia for all fish GBS isolates and only in 3.2 % (3-4.2 %) human isolates. For fish isolates, all consisted a plasmid less than 6 kb and belonged to ST7 type, which includes mainly pulsotypes I and Ia, with a difference in a deletion at the largest DNA fragment. These fish isolates were susceptible to all antimicrobials tested in 2007 and increased in non-susceptibility to penicillin, and resistance to clindamycin and ceftriaxone in 2011. Differing in pulsotype and lacking plasmid from fish isolates, human serotype Ia isolates were separated into eight pulsotypes II-IX. Main clone ST23 included pulsotypes II and IIa (50 %) and ST483 consisted of pulsotype III. Human serotype Ia isolates were all susceptible to ceftriaxone and penicillin and few were resistant to erythromycin, azithromycin, clindamycin, levofloxacin and moxifloxacine with the resistant rate of 20 % or less. Using tilapia to analyze the pathogenesis, fish isolates could cause more severe symptoms, including hemorrhage of the pectoral fin, hemorrhage of the gill, and viscous black and common scites, and mortality (>95 % for pulsotype I) than the human isolates (<30 %); however, the fish pulostype Ia isolate 912 with deletion caused less symptoms and the lowest mortality (<50 %) than pulsotype I isolates. CONCLUSION: Genetic, pathogenic, and antimicrobial differences demonstrate diverse origin of human and fish serotype Ia isolates. The pulsotype Ia of fish serotype Ia isolates may be used as vaccine strains to prevent the GBS infection in fish.


Assuntos
Doenças dos Peixes/microbiologia , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/classificação , Streptococcus agalactiae/genética , Animais , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Farmacorresistência Bacteriana Múltipla , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus agalactiae/isolamento & purificação , Taiwan
11.
BMC Infect Dis ; 16: 276, 2016 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-27287530

RESUMO

BACKGROUND: Staphylococcus aureus is associated with human skin and soft tissue infections (SSTIs); however, the involvement of virulence factors in different clinical presentations is unclear. METHODS: We analyzed methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) strains from Taiwan to determine correlations among the clinical characteristics of SSTIs, antimicrobial susceptibility and virulence factors of S. aureus with specific genetic backgrounds. RESULTS: We identified 177 MRSA isolates and 130 MSSA isolates among the 307 SSTI-associated S. aureus isolates. Hospital-acquired (HA)- and community-acquired (CA)-MRSA isolates accounted for 61.6 % and 38.4 % of the isolates, respectively. Clinical presentations in SSTI patients differed significantly for the disease groups. Deep-seated MRSA infections presented with higher amputation rate than MSSA infections. MRSA isolates were all susceptible to linezolid, teicoplanin, and vancomycin, and >94 % of isolates were erythromycin- and clindamycin-resistant. Staphylococcal cassette chromosome (SCCmec) types IV, V, and VII were the most frequent in the CA-MRSA group (n = 68); types III, IV and V were the most frequent in the HA-MRSA group (n = 109). Panton-Valentine leukocidin (PVL) genes were significantly more frequent in CA-MRSA strains (75.0 %) than in HA-MRSA (33.0 %) and MSSA (24.6 %) and were found in 66.7 % (74/111) strains isolated from the abscess group. Exfoliatin A genes were more common in catheter-related exit-site MSSA infections (37.5 %) compared with other MSSA disease groups (P < 0.05). Exfoliatin B and superantigen exotoxin genes were uncommon in all SSTI disease types. Pulsotypes A (ST239), C, and D (ST59) were the predominant MRSA genotypes in deep-seated infections. CONCLUSIONS: If not treated appropriately, deep-seated MRSA-associated infections present with higher amputation rates than deep-seated MSSA-associated infections. PVL-positive MRSA strains caused more frequently pus-forming lesions and less bacteremia and invasive diseases. Methods for discriminating CA-MRSA from HA-MRSA strains are now unreliable due to circulation of both ST 239 and ST 59 strains in the community and nosocomial settings. Initial antibiotic treatments should consider MRSA for patients with SSTIs in areas where MRSA is prevalent.


Assuntos
Staphylococcus aureus Resistente à Meticilina/genética , Infecções dos Tecidos Moles/microbiologia , Infecções Cutâneas Estafilocócicas/microbiologia , Adulto , Idoso , Antibacterianos/farmacologia , Bacteriemia/microbiologia , Toxinas Bacterianas/genética , Infecções Relacionadas a Cateter/microbiologia , Clindamicina , Infecções Comunitárias Adquiridas/microbiologia , Infecção Hospitalar/microbiologia , Eritromicina , Exfoliatinas/genética , Exotoxinas/genética , Feminino , Genótipo , Humanos , Leucocidinas/genética , Linezolida , Masculino , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Pessoa de Meia-Idade , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Superantígenos/genética , Taiwan , Teicoplanina , Vancomicina , Fatores de Virulência/genética
12.
Biomed Rep ; 4(3): 349-354, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26998274

RESUMO

Resveratrol (Re), a stilbenoid, is associated with a potential benefit in controlling certain biomarkers in type II diabetes. Genistein (Ge), a phytoestrogen, may act as an antioxidant and thus may diminish damaging effects of free radicals in tissues. In the present study, a potential synergistic antioxidant effect of an Re/Ge combination on high-glucose (HG) incubation in Madin-Darby canine kidney (MDCK) epithelial cells was evaluated. Compared with the treatment of Re or Ge alone, the Re/Ge combination synergistically decreased intracellular reactive oxygen species (ROS) and hydroxyl radicals in MDCK cells. This synergistic antioxidant effect correlated with the inhibition of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase expression and an increase in γ-glutamylcysteine synthetase expression. In addition, mitochondrial complex I, NADPH oxidase, xanthine oxidase and lipoxygenase contributed towards ROS overproduction when the MDCK cells were incubated with HG. In conclusion, the Re/Ge combination synergistically enhanced the antioxidant effect in HG-incubated kidney cells, possibly through an enhanced antioxidant regulation mechanism. The Re/Ge combination may be a potential benefit against oxidative stress in diabetes mellitus.

13.
J Microbiol Immunol Infect ; 49(6): 892-901, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25592882

RESUMO

BACKGROUND/PURPOSE: Escherichia coli is a common pathogen to cause clinical and subclinical mastitis in cows. A total of 57 E. coli isolates from raw milk from cows were characterized genetically and biochemically. METHODS: Extended-spectrum ß-lactamase (ESBL) genes, the mechanism for fluoroquinolone resistance, and variations in virulence genes and genomes of these E. coli isolates were investigated by the antimicrobial susceptibility test, simplex and multiplex polymerase chain reaction (PCR), and pulsed-field gel electrophoresis (PFGE). RESULTS: All E. coli isolates were resistant to cloxacillin (100%) and to a lesser extent (50%) to tetracycline, neomycin, gentamycin, ampicillin, ceftriaxone, cefotaxime (CTX), and ceftazidime (CAZ). Nearly 70% of the isolates were resistant to at least two antimicrobials and 28.1% carried AmpA and AmpC genes simultaneously. The predominant bla gene was blaTEM, followed by blaCMY, blaCTX, blaSHV, and blaDHA. Among the six (10.5%) ESBL-producing E. coli carrying blaCTX-M15, blaCTX-M55, or blaCTX-M14, two isolates 31 of ST410 in the ST23 complex and 58 of ST167 in the ST10 complex were also resistant to ciprofloxacin, enrofloxacin, and levofloxacin, with mutations at codon 83 from serine to leucine and codon 87 from aspartic acid to asparagine in GyrA and at codon 80 from serine to isoleucine in ParC. These isolates were genetically diverse in pulsotype analysis, lacked toxin genes of human pathogenic E. coli and carried mostly the prevalent virulence genes fimH, papGII, and α-hemolysin. CONCLUSION: Lacking virulence genes examined, genetic diverse E. coli isolates are unrelated to human pathogenic E. coli. Enhancing sanitation in milk processing and transportation is needed to eliminate multidrug-resistant (MDR), fluoroquinolone-resistant, and ESBL-producing E. coli isolates.


Assuntos
Antibacterianos/farmacologia , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Fluoroquinolonas/farmacologia , Mastite Bovina/microbiologia , Leite/microbiologia , Resistência beta-Lactâmica/genética , beta-Lactamases/genética , Animais , Proteínas de Bactérias/genética , Bovinos , Cloxacilina/farmacologia , Eletroforese em Gel de Campo Pulsado , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Feminino , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase Multiplex , Taiwan
14.
J Microbiol Immunol Infect ; 49(5): 672-678, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26316010

RESUMO

BACKGROUND: Streptococcus agalactiae [group B Streptococcus (GBS)] has become more prevalent in nonpregnant women, the elderly, and people who are immunocompromised. We investigated the serotype and genomic changes of GBS human isolates from different hospitals from 2007 to 2012. METHODS: The serotype and genotype of 658 GBS human isolates were determined with multiplex polymerase chain reaction and pulsed field gel electrophoresis analysis. Multilocus sequence typing analysis determined the sequence type (ST) of the major clones of serotypes Ib, V, and VI. RESULTS: Most of the isolates were collected from urine samples (60.5%) with a reduction in the rate from 74.6% in 2007 to 34.5% in 2012 and from infected patients older than 30 years (72.6%). The female/male ratio differed depending on the source: 3.52 in the urine group, 0.48 in the wound group, and 0.43 in pus. Serotypes Ib (16.5%), III (16.9%), V (27.2%), and VI (17.6%) were the most predominant among the nine serotypes identified and were separated into two prevalence patterns: a decrease in serotypes Ib and V and an increase in serotypes III and VI from 2007 to 2012. The prevalence change was associated with the urine group. Additionally, serotype VI become more prevalent in blood samples in four hospitals. The pulsed field gel electrophoresis analysis demonstrated three genetic patterns: limited pulsotypes and a major clonal dissemination for serotypes Ib and V, diverse pulsotypes for serotypes III, and diverse pulsotypes with a major clonal dissemination for serotype VI. Multilocus sequence typing analysis of the major clones identified ST12 for serotype Ib and ST1 for serotypes V and VI. CONCLUSION: Rapid genomic variations with different evolutionary patterns have led to the establishment of serotypes III and VI as the predominant GBS serotypes.


Assuntos
Antibacterianos/uso terapêutico , Variação Genética , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/epidemiologia , Streptococcus agalactiae/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Farmacorresistência Bacteriana Múltipla , Eletroforese em Gel de Campo Pulsado , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase Multiplex , Sorogrupo , Sorotipagem , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus agalactiae/isolamento & purificação , Taiwan/epidemiologia , Adulto Jovem
15.
J Microbiol Immunol Infect ; 48(6): 647-54, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24863496

RESUMO

BACKGROUND: The misuse of antimicrobial agents increases drug resistance in bacteria. METHODS: The correlation between antimicrobial agent consumption and related resistance in the Gram-negative bacteria Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Proteus mirabilis was analyzed during the period 2003-2011. RESULTS: Among these five bacteria, overall E. coli and K. pneumoniae were more commonly isolated from bloodstream than the other species. Regarding Enterobacteriaceae, E. coli and K. pneumoniae showed annual increases of resistance to the tested antimicrobial agents; conversely, P. mirabilis exhibited reduced resistance to cefuroxime, ceftriaxone and cefepime. In contrast to the relatively low antimicrobial resistance in P. aeruginosa, A. baumannii revealed high resistance, which was over 85% resistant rate to the tested antimicrobial agents and over 80% carbapenem resistance in 2011. E. coli, K. pneumoniae, and P. mirabilis differed in development of antimicrobial resistance after consumption of the antimicrobial agents. K. pneumoniae developed resistance to all antimicrobial groups, whereas resistance in P. mirabilis was not related to any antimicrobial consumption. P. aeruginosa developed resistance to ß-lactam antimicrobials and aminoglycosides, whereas A. baumanii developed resistance to carbapenems after their use. CONCLUSION: The development of antimicrobial resistance was related to antimicrobial agents and bacterial species.


Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Técnicas de Tipagem Bacteriana , Infecções por Bactérias Gram-Negativas/microbiologia , Hospitais , Humanos , Testes de Sensibilidade Microbiana , Estudos Retrospectivos
16.
Biomed J ; 38(3): 215-20, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25179723

RESUMO

BACKGROUND: Antimicrobial resistance of Streptococcus agalactiae (Group B Streptococcus, GBS) has been emerging worldwide. We aimed to examine the correlation of drug-resistant genes with serotypes and with the mutations of the quinolone resistance-determining region (QRDR) in GBS isolates. METHODS: A total of 323 human GBS isolates were collected from a hospital in southern Taiwan. Laboratory investigation included serotyping by a multiplex polymerase chain reaction (PCR) method, antimicrobial susceptibility testing by a disc diffusion method, and mechanism analysis of the resistance to macrolides and fluoroquinolones by PCR and sequencing methods. RESULTS: Multiplex PCR showed that the most prevalent serotypes were Ib, III, V, and VI, mostly isolated from urine. The ermB gene was highly prevalent in serotypes Ib and V and was associated with clindamycin and macrolide resistance. GBS with a serine-to-leucine mutation at codon 81 in GyrA and with a serine-to-phenylalanine or -tyrosine mutation at codon 79 in ParC had a higher minimum inhibitory concentration of levofloxacin than isolates with only an aspartic acid-to-tyrosine mutation at codon 83 (>32 µg/ml vs. 16 µg/ml) in GyrA. CONCLUSIONS: The most prevalent GBS serotypes were Ib, III, V, and VI. The ermB and mefE genes carried in serotypes Ib and V were highly associated with the resistance to macrolides and clindamycin. Mutations at codon 79 and codon 83 of ParC were the major determining factors for high-level fluoroquinolone resistance.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Fluoroquinolonas/farmacologia , Macrolídeos/farmacologia , Sorogrupo , Infecções Estreptocócicas/microbiologia , Streptococcus agalactiae/genética , Hospitais , Humanos , Testes de Sensibilidade Microbiana , Sorotipagem/métodos , Streptococcus agalactiae/isolamento & purificação , Taiwan
17.
J Biomed Sci ; 21: 78, 2014 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-25135473

RESUMO

BACKGROUND: The green fluorescence protein (GFP)-associated fluorescence method and the luciferase-associated bioluminescence method are the two major methods for IVIS imaging system to investigate the bacterial infection in animal models. The aim of this study was to evaluate the infection route of Gram-negative bacteria carrying a stable and broad range of conjugative bioluminescence plasmid pSE-Lux1 in a mouse model. RESULTS: Both encapsulated and non-encapsulated Gram-negative bacteria were used as hosts to evaluate conjugation efficiency and plasmid stability of pSE-Lux1, a recombinant of pSE34 and luxABCDE operon. The plasmid conjugation efficiencies of pSE-Lux1 ranged from 10⁻³ to 10⁻7 in various Gram-negative bacteria. Plasmid pSE-Lux1 maintained in Escherichia coli, Klebsiella pneumoniae, and Salmonella enterica serovars Choleraesues (abbreviated S. Choleraesuis) and Typhimurium (S. Typhimurium), than in Acinetobacter baumannii and Serratia marcescens, was shown to be of better stability for at least four days. To investigate systemic bacterial infections, K. pneumoniae strain CG354 was intravenously injected, and then was clearly observed to be non-pathogenic to Balb/c mice for a long-term bioluminescence monitoring for 6 days. For examining dynamic distributions of gastrointestinal tract infection, the invasion protein SipB-deficient mutant OU5045△sipB and OU5046△sipB of S. serovar Typhimurium constructed in this study, compared to wild-type strain OU5045 and its virulence plasmid-less strain OU5046, were of less virulence to mice. CONCLUSIONS: This is the first study to evaluate the conjugative and stable bioluminescence vehicle system of pSE-Lux1 in a wide range of Gram-negative bacteria, a system that can provide a useful reporter approach to trace systemic and gastrointestinal bacterial infections in a mouse model.


Assuntos
Bactérias Gram-Negativas , Infecções por Bactérias Gram-Negativas , Proteínas de Fluorescência Verde , Medições Luminescentes , Imagem Molecular , Plasmídeos , Animais , Bactérias Gram-Negativas/genética , Bactérias Gram-Negativas/metabolismo , Infecções por Bactérias Gram-Negativas/genética , Infecções por Bactérias Gram-Negativas/metabolismo , Infecções por Bactérias Gram-Negativas/patologia , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Camundongos , Camundongos Endogâmicos BALB C
18.
Int J Infect Dis ; 26: 140-5, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25058125

RESUMO

OBJECTIVE: This study aimed to investigate the clinical and microbiological features of recurrent group B streptococcal (GBS) diseases among non-pregnant adults. METHODS: All hospitalized non-pregnant adults who had culture-proven GBS infections between January 2008 and December 2010 were enrolled in this retrospective study. Bacterial isolates were examined for their serotypes, genotypes, and antimicrobial resistance. RESULTS: The recurrence rate of GBS infection in Taiwan was found to be 9.3%. Of the 70 recurrent episodes in 32 patients, infections of the urinary tract (U) were diagnosed clinically in 55.7%, infections of the soft tissue (S) in 31.4%, and infections of the bloodstream (B) in 12.9%. The initial/recurrent episodes in 25 patients were mainly U/U (40.6%), followed by S/S (18.8%) and B/B (6.2%). The serotypes/serogroups identified were serotypes V (34.3%), Ib (22.9%), VI (17.1%), III (12.9%), IV (7.1%), and Ia (5.7%). Recurrent strains showed less resistance to erythromycin or clindamycin than non-recurrent strains. Six distinct genotypes were identified in 12 serotype VI isolates derived from seven patients; five of these isolate pairs had identical genotypes. CONCLUSIONS: Recurrent GBS diseases were found to occur considerably more often than previously thought, mainly in adults with a high comorbid index. Relapse, not new acquisition, was found to be more common.


Assuntos
Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/microbiologia , Streptococcus agalactiae , Adulto , Idoso , Farmacorresistência Bacteriana , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Sorogrupo , Sorotipagem , Streptococcus agalactiae/classificação , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus agalactiae/genética , Streptococcus agalactiae/isolamento & purificação , Taiwan
19.
PLoS One ; 8(3): e60704, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23556001

RESUMO

The consumption of cetacean meat is geographically common and often of undetermined sustainability. Besides, it can expose humans to contaminants and zoonotic pathogens. The illegality of possessing cetacean meat was likely under-reported in some countries due to lack of attention paid by the officials although DNA analysis of market products helped to show such practices. We developed two monoclonal antibodies against synthetic peptides of myoglobin (Mb) for constructing a rapid immune colloidal gold strip. Only cetacean Mb is capable of binding to both antibodies and presents positive signal while the Mb from other animals can bind only 1 of the antibodies and presents negative result. The strip for cetacean meat would be an applicable and cost-effective test for field inspectors and even the general public. It contributes to increase the reporting capacity and coverage of illegal cetacean meat possession, which has implications for global cetacean conservation and public health.


Assuntos
Anticorpos Monoclonais/imunologia , Cetáceos/imunologia , Coloide de Ouro , Carne/análise , Mioglobina/análise , Fitas Reagentes/análise , Sequência de Aminoácidos , Animais , Feminino , Coloide de Ouro/química , Humanos , Imunoensaio/instrumentação , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Mioglobina/imunologia , Peptídeos/análise , Peptídeos/imunologia , Saúde Pública , Sensibilidade e Especificidade
20.
Foodborne Pathog Dis ; 10(3): 256-62, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23489048

RESUMO

A total of 117 mastitis-associated Staphylococcus aureus isolates from cow, goat, and human patients were analyzed for differences in antibiotic susceptibility, virulence genes, and genotypes using accessory gene regulator (agr) typing, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Multidrug-resistant (MDR) S. aureus were commonly found in all sources, though they were predominantly found in human and goat isolates. Almost 70% of the isolates were resistant to ampicillin and penicillin. Host-associated virulence genes were identified as follows: tst, a gene encoding toxic shock syndrome toxin, was found in goat isolates; lukED and lukM, genes encoding leukocidin, found in cow isolates; lukPV, a gene encoding leukocidin, found in human isolates; and eta, a gene encoding for exfoliative toxin, found in both human and cow isolates. All four types of hemolysin, α, ß, γ, and δ, were identified in human isolates, three types (α, γ, and δ), were identified in cow isolates, and two types (α and δ) were identified in goat isolates. Agr-typing determined agr1 to be the main subtype in human and cow isolates. PFGE and MLST analysis revealed the presence of diverse genotypes among the three sources. In conclusion, mastitis-associated, genetically diverse strains of MDR S. aureus differed in virulence genes among human, cow, and goat isolates.


Assuntos
DNA Bacteriano/isolamento & purificação , Mastite/veterinária , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Fatores de Virulência/genética , Ampicilina/farmacologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bovinos , Farmacorresistência Bacteriana Múltipla , Eletroforese em Gel de Campo Pulsado , Cabras , Humanos , Mastite/microbiologia , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Penicilinas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Taiwan , Transativadores/genética , Transativadores/metabolismo , Virulência
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA