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1.
Lipids Health Dis ; 23(1): 338, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39415186

RESUMO

Acute myocardial infarction (AMI) and related cardiovascular disease complications are the leading causes of mortality worldwide. Brown adipose tissue (BAT) is thermogenic and characterized by the uncoupling protein expression. Recent studies have found that in cardiovascular diseases, activated BAT can effectively improve the prognosis of AMI and concurrent heart failure through intercellular communication. However, a clear and systematic understanding of the myocardial protective mechanism of BAT after AMI is lacking, especially in the endocrine function of BAT. This review describes the effects of BAT on various cells in the heart after AMI. BAT plays a protective role on cardiac cells and fibroblasts during ischemia/reperfusion (I/R), myocardial remodeling, and myocardial fibrosis. This review also discusses the changes caused by BAT activation in different stages of heart failure. Finally, this review summarizes the treatment methods that target BAT to improve AMI. Further in-depth researches are still needed to clarify the underlying mechanism of the connection between BAT and different cells in cardiac tissue in order to identify potential therapeutic targets.


Assuntos
Tecido Adiposo Marrom , Insuficiência Cardíaca , Infarto do Miocárdio , Infarto do Miocárdio/patologia , Infarto do Miocárdio/metabolismo , Humanos , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Marrom/patologia , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/metabolismo , Animais , Miocárdio/patologia , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Fibroblastos/metabolismo , Fibroblastos/patologia
2.
Lett Appl Microbiol ; 77(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38327245

RESUMO

Antibiotic resistance in Citrobacter freundii is a public health concern. This study evaluated the closed genome of a C. freundii isolated from the stool of a hospitalized patient initially related to a Salmonella outbreak. Confirmation of the isolate was determined by whole-genome sequencing. Nanopore sequencing was performed using a MinION with a Flongle flow cell. Assembly using SPAdes and Unicycler yielded a closed genome annotated by National Center for Biotechnology Information Prokaryotic Genome Annotation Pipeline. Genomic analyses employed MLST 2.0, ResFinder4.1, PlasmidFinder2.1, and VFanalyzer. Phylogenetic comparison utilized the Center for Food Safety and Applied Nutrition (CFSAN)-single nucleotide polymorphism pipeline and Genetic Algorithm for Rapid Likelihood Inference. Antimicrobial susceptibility was tested by broth microdilution following Clinical and Laboratory Standards Institute criteria. Multi-locus sequence type in silico analysis assigned the C. freundii as sequence type 64 and the blaCMY-41 gene was detected in resistome investigation. The susceptibility to antibiotics, determined using Sensititre® plates, revealed resistance to aztreonam, colistin, cefoxitin, amoxicillin/clavulanic acid, sulfisoxazole, ampicillin, and streptomycin. The genetic relatedness of the C. freundii CFSAN077772 with publicly available C. freundii genomes revealed a close relationship to a C. freundii SRR1186659, isolated in 2009 from human stool in Tanzania. In addition, C. freundii CFSAN077772 is nested in the same cluster with C. freundii clinical strains isolated in Denmark, Mexico, Myanmar, and Canada, suggesting a successful intercontinental spread.


Assuntos
Citrobacter freundii , Infecções por Enterobacteriaceae , Humanos , Citrobacter freundii/genética , beta-Lactamases/genética , Tipagem de Sequências Multilocus , Filogenia , Infecções por Enterobacteriaceae/epidemiologia , Antibacterianos/farmacologia , Genômica , Testes de Sensibilidade Microbiana
3.
Lett Appl Microbiol ; 76(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36688781

RESUMO

Salmonella enterica subsp. enterica serovar Enteritidis (SE) has become the prevalent serovar isolated from gastroenteritis cases in Brazil since the 1990s. To better understand the genomic diversity and phylogenetic relationship amongst SE epidemic isolates from Brazil, 30 SE isolates from a variety of implicated foods and case patients of outbreaks between 1999 and 2006 were selected for genome comparison analyses. SE genomes were also compared against publicly available Brazilian SE isolates from pre- and postepidemic period. MLST analysis revealed that all isolates belong to sequence type (ST) 11. A total of seven Salmonella pathogenicity islands (SPIs) (SPI-1, SPI-3-5, SPI-13, SPI14, and C63PI) were identified in the evaluated genomes and all studied SE genomes carried similar prophage profiling. Resistome analysis revealed the presence of resistance genes to aminoglycosides [aac(6')laa, aph(3")-lb, aph(6)-ld], as well as point mutations in gyrA. Phylogenetic analysis demonstrated that certain isolates have circulated in Brazil for years and been involved in distinct outbreaks.


Assuntos
Salmonella enterica , Salmonella enteritidis , Humanos , Filogenia , Brasil , Tipagem de Sequências Multilocus , Genômica , Surtos de Doenças
4.
Int J Mol Sci ; 23(21)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36362052

RESUMO

Neutrophils play a pivotal role in innate immunity by releasing neutrophils extracellular traps (NETs). Excessive NETs are detrimental to the local tissue and further exacerbate inflammation. Protein arginine deiminases (PAD) mediate histone citrullination and NET formation that, in turn, exacerbate endotoxin shock damages. In this study, we further investigated the molecular mechanism underlying PAD and NETs in endotoxic stress in mice. The control group mice were injected with solvent, the LPS endotoxic shock group mice were intraperitoneally injected with LPS at 35 mg/kg only, while the LPS and PAD inhibitor YW3-56 treatment group mice were injected with YW3-56 at 10 mg/kg prior to the LPS injection. YW3-56 significantly prolonged the survival time of the LPS-treated mice. NETs, cfDNA, and inflammatory factors were detected by ELISA in serum, paitoneal cavity, and lung at 24 h after LPS administration. Lung injuries were detected by immunostaining, and lung tissue transcriptomes were analyzed by RNA-seq at 24 h after LPS administration. We found that YW3-56 altered neutrophil tissue homeostasis, inhibited NET formation, and significantly decreased cytokines (IL-6, TNFα and IL-1ß) levels, cytokines gene expression, and lung tissue injury. In summary, NET formation inhibition offers a new avenue to manage inflammatory damages under endotoxic stress.


Assuntos
Armadilhas Extracelulares , Inflamação , Choque Séptico , Animais , Camundongos , Citocinas/metabolismo , Armadilhas Extracelulares/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipopolissacarídeos/toxicidade , Lipopolissacarídeos/metabolismo , Neutrófilos/metabolismo , Desiminases de Arginina em Proteínas/antagonistas & inibidores , Desiminases de Arginina em Proteínas/metabolismo , Choque Séptico/induzido quimicamente , Choque Séptico/tratamento farmacológico , Choque Séptico/metabolismo
5.
Genomics ; 112(1): 528-544, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30974149

RESUMO

A total of 91 draft genome sequences were used to analyze isolates of Salmonella enterica serovar Enteritidis obtained from feral mice caught on poultry farms in Pennsylvania. One objective was to find mutations disrupting open reading frames (ORFs) and another was to determine if ORF-disruptive mutations were present in isolates obtained from other sources. A total of 83 mice were obtained between 1995-1998. Isolates separated into two genomic clades and 12 subgroups due to 742 mutations. Nineteen ORF-disruptive mutations were found, and in addition, bigA had exceptional heterogeneity requiring additional evaluation. The TRAMS algorithm detected only 6 ORF disruptions. The sefD mutation was the most frequently encountered mutation and it was prevalent in human, poultry, environmental and mouse isolates. These results confirm previous assessments of the mouse as a rich source of Salmonella enterica serovar Enteritidis that varies in genotype and phenotype.


Assuntos
Mutação , Salmonella enteritidis/genética , Algoritmos , Animais , Fazendas , Genoma Bacteriano , Mutação INDEL , Camundongos , Repetições Minissatélites , Fenótipo , Filogenia , Polimorfismo de Nucleotídeo Único , Aves Domésticas , Salmonella enteritidis/classificação , Salmonella enteritidis/isolamento & purificação , Sequenciamento Completo do Genoma
6.
Microb Pathog ; 149: 104264, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32464302

RESUMO

This study had as aims to evaluate the effects of successive exposures to Mentha piperita L. essential oil (MPEO) on culturability and physiological functions of Salmonella Typhimurium PT4. S. Typhimurium PT4 cells (108 log CFU/mL) were exposed to the same (1.25 µL/mL) or increasing MPEO concentrations (1.25-80 µL/mL) during 252 h. At each 36-h interval, the viable cell counts, and distinct cell functions were assessed using plate counting and flow cytometry, respectively. As the exposure time to the same MPEO concentration increased, the population of S. Typhimurium PT4 cells with damaged, permeabilized and depolarized membrane, and compromised efflux activity decreased. Otherwise, S. Typhimurium PT4 cells with damaged membrane physiological functions increased over the exposure to increasing concentrations of MPEO. Genomic analyses showed that the strain carries 17 genes associated with stress responses and the persistence of the tested strain among sources associated with poultry spanning more than 16 years and its virulence for humans. Therefore, successive exposure to a sublethal concentration of MPEO induced S. Typhimurium PT4 cells capable of maintaining the membrane integrity and its functions despite their non-culturable state.


Assuntos
Epidemias , Óleos Voláteis , Humanos , Mentha piperita , Óleos Voláteis/farmacologia , Extratos Vegetais , Salmonella typhimurium/genética
7.
Foodborne Pathog Dis ; 15(6): 361-371, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29620958

RESUMO

Multidrug-resistant (MDR) plasmids play an important role in disseminating antimicrobial resistance genes. To elucidate the antimicrobial resistance gene compositions in A/C incompatibility complex (IncA/C) plasmids carried by animal-derived MDR Salmonella Newport, and to investigate the spread mechanism of IncA/C plasmids, this study characterizes the complete nucleotide sequences of IncA/C plasmids by comparative analysis. Complete nucleotide sequencing of plasmids and chromosomes of six MDR Salmonella Newport strains was performed using PacBio RSII. Open reading frames were assigned using prokaryotic genome annotation pipeline (PGAP). To understand genomic diversity and evolutionary relationships among Salmonella Newport IncA/C plasmids, we included three complete IncA/C plasmid sequences with similar backbones from Salmonella Newport and Escherichia coli: pSN254, pAM04528, and peH4H, and additional 200 draft chromosomes. With the exception of canine isolate CVM22462, which contained an additional IncI1 plasmid, each of the six MDR Salmonella Newport strains contained only the IncA/C plasmid. These IncA/C plasmids (including references) ranged in size from 80.1 (pCVM21538) to 176.5 kb (pSN254) and carried various resistance genes. Resistance genes floR, tetA, tetR, strA, strB, sul, and mer were identified in all IncA/C plasmids. Additionally, blaCMY-2 and sugE were present in all IncA/C plasmids, excepting pCVM21538. Plasmid pCVM22462 was capable of being transferred by conjugation. The IncI1 plasmid pCVM22462b in CVM22462 carried blaCMY-2 and sugE. Our data showed that MDR Salmonella Newport strains carrying similar IncA/C plasmids clustered together in the phylogenetic tree using chromosome sequences and the IncA/C plasmids from animal-derived Salmonella Newport contained diverse resistance genes. In the current study, we analyzed genomic diversities and phylogenetic relationships among MDR Salmonella Newport using complete plasmids and chromosome sequences and provided possible spread mechanism of IncA/C plasmids in Salmonella Newport Lineage II.


Assuntos
Doenças dos Bovinos/microbiologia , Galinhas/microbiologia , Doenças do Cão/microbiologia , Doenças das Aves Domésticas/microbiologia , Carne Vermelha/microbiologia , Salmonelose Animal/microbiologia , Salmonella/genética , Animais , Bovinos , Cães , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Filogenia , Plasmídeos/genética , Salmonella/efeitos dos fármacos , Salmonella/isolamento & purificação , Análise de Sequência de DNA/veterinária
8.
Appl Environ Microbiol ; 83(16)2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28550057

RESUMO

Escherichia coli serotype O157:H7 is a zoonotic food- and waterborne bacterial pathogen that causes a high hospitalization rate and can cause life-threatening complications. Increasingly, E. coli O157:H7 infections appear to originate from fresh produce. Ruminants, such as cattle, are a prominent reservoir of E. coli O157:H7 in the United States. California is one of the most agriculturally productive regions in the world for fresh produce, beef, and milk. The close proximity of fresh produce and cattle presents food safety challenges on a uniquely large scale. We performed a survey of E. coli O157:H7 on 20 farms in California to observe the regional diversity and prevalence of E. coli O157:H7. Isolates were obtained from enrichment cultures of cow feces. Some farms were sampled on two dates. Genomes from isolates were sequenced to determine their relatedness and pathogenic potential. E. coli O157:H7 was isolated from approximately half of the farms. The point prevalence of E. coli O157:H7 on farms was highly variable, ranging from zero to nearly 90%. Within farms, generally one or a few lineages were found, even when the rate of isolation was high. On farms with high isolation rates, a single clonal lineage accounted for most of the isolates. Farms that were visited months after the first visit might have had the same lineages of E. coli O157:H7. Strains of E. coli O157:H7 may be persistent for months on farms.IMPORTANCE This survey of 20 cow-calf operations from different regions of California provides an in depth look at resident Escherichia coli O157:H7 populations at the molecular level. E. coli O157:H7 is found to have a highly variable prevalence, and with whole-genome sequencing, high prevalences in herds were found to be due to a single lineage shed from multiple cows. Few repeat lineages were found between farms in this area; therefore, we predict that E. coli O157:H7 has significant diversity in this area beyond what is detected in this survey. All isolates from this study were found to have pathogenic potential based on the presence of key virulence gene sequences. This represents a novel insight into pathogen diversity within a single subtype and will inform future attempts to survey regional pathogen populations.


Assuntos
Doenças dos Bovinos/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli O157/isolamento & purificação , Animais , California/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Escherichia coli O157/classificação , Escherichia coli O157/genética , Fezes/microbiologia , Genômica , Filogenia
9.
Appl Environ Microbiol ; 82(13): 3900-3912, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27107118

RESUMO

UNLABELLED: Escherichia coli O26 is the second most important enterohemorrhagic E. coli (EHEC) serogroup worldwide. Serogroup O26 strains are categorized mainly into two groups: enteropathogenic (EPEC) O26, carrying a locus of enterocyte effacement (LEE) and mostly causing mild diarrhea, and Shiga-toxigenic (STEC) O26, which carries the Shiga toxin (STX) gene (stx), responsible for more severe outcomes. stx-negative O26 strains can be further split into two groups. One O26 group differs significantly from O26 EHEC, while the other O26 EHEC-like group shows all the characteristics of EHEC O26 except production of STX. In order to determine the different populations of O26 E. coli present in U.S. cattle, we sequenced 42 O26:H11 strains isolated from feedlot cattle and compared them to 37 O26:H11 genomes available in GenBank. Phylogenetic analysis by whole-genome multilocus sequence typing (wgMLST) showed that O26:H11/H(-) strains in U.S. cattle were highly diverse. Most strains were sequence type 29 (ST29). By wgMLST, two clear lineages could be distinguished among cattle strains. Lineage 1 consisted of O26:H11 EHEC-like strains (ST29) (4 strains) and O26:H11 EHEC strains (ST21) (2 strains), and lineage 2 (36 strains) consisted of O26:H11 EPEC strains (ST29). Overall, our analysis showed U.S. cattle carried pathogenic (ST21; stx1 (+) ehxA(+) toxB(+)) and also potentially pathogenic (ST29; ehxA(+) toxB(+)) O26:H11 E. coli strains. Furthermore, in silico analysis showed that 70% of the cattle strains carried at least one antimicrobial resistance gene. Our results showed that whole-genome sequence analysis is a robust and valid approach to identify and genetically characterize E. coli O26:H11, which is of importance for food safety and public health. IMPORTANCE: Escherichia coli O26 is the second most important type of enterohemorrhagic E. coli (EHEC) worldwide. Serogroup O26 strains are categorized into two groups: enteropathogenic (EPEC) carrying LEE, causing mild diarrhea, and Shiga toxigenic (STEC) carrying the stx gene, responsible for more severe outcomes. However, there are currently problems in distinguishing one group from the other. Furthermore, several O26 stx-negative strains are consistently misidentified as either EHEC-like or EPEC. The use of whole-genome sequence (WGS) analysis of O26 strains from cattle in the United States (i) allowed identification of O26 strains present in U.S. cattle, (ii) determined O26 strain diversity, (iii) solved the misidentification problem, and (iv) screened for the presence of antimicrobial resistance and virulence genes in the strains. This study provided a framework showing how to easily and rapidly use WGS information to identify and genetically characterize E. coli O26:H11, which is important for food safety and public health.


Assuntos
Infecções por Escherichia coli/veterinária , Escherichia coli/classificação , Escherichia coli/isolamento & purificação , Genes Bacterianos , Variação Genética , Genoma Bacteriano , Fatores de Virulência/análise , Animais , Bovinos , Escherichia coli/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Filogenia , Estados Unidos/epidemiologia , Fatores de Virulência/genética
10.
Appl Environ Microbiol ; 81(2): 569-77, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25381234

RESUMO

Escherichia coli O157:H7 is, to date, the major E. coli serotype causing food-borne human disease worldwide. Strains of O157 with other H antigens also have been recovered. We analyzed a collection of historic O157 strains (n = 400) isolated in the late 1980s to early 1990s in the United States. Strains were predominantly serotype O157:H7 (55%), and various O157:non-H7 (41%) serotypes were not previously reported regarding their pathogenic potential. Although lacking Shiga toxin (stx) and eae genes, serotypes O157:H1, O157:H2, O157:H11, O157:H42, and O157:H43 carried several virulence factors (iha, terD, and hlyA) also found in virulent serotype E. coli O157:H7. Pulsed-field gel electrophoresis (PFGE) showed the O157 serogroup was diverse, with strains with the same H type clustering together closely. Among non-H7 isolates, serotype O157:H43 was highly prevalent (65%) and carried important enterohemorrhagic E. coli (EHEC) virulence markers (iha, terD, hlyA, and espP). Isolates from two particular H types, H2 and H11, among the most commonly found non-O157 EHEC serotypes (O26:H11, O111:H11, O103:H2/H11, and O45:H2), unexpectedly clustered more closely with O157:H7 than other H types and carried several virulence genes. This suggests an early divergence of the O157 serogroup to clades with different pathogenic potentials. The appearance of important EHEC virulence markers in closely related H types suggests their virulence potential and suggests further monitoring of those serotypes not implicated in severe illness thus far.


Assuntos
Infecções por Escherichia coli/microbiologia , Escherichia coli O157/classificação , Escherichia coli O157/genética , Variação Genética , Fatores de Virulência/genética , Eletroforese em Gel de Campo Pulsado , Escherichia coli O157/isolamento & purificação , Evolução Molecular , Humanos , Epidemiologia Molecular , Tipagem Molecular , Sorogrupo , Estados Unidos
11.
J Antimicrob Chemother ; 69(10): 2644-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24908046

RESUMO

OBJECTIVES: To examine the distribution of all genes known to be responsible for resistance to quaternary ammonium compounds (QACs), and their association with resistance to QACs and other antimicrobials, in Escherichia coli recovered from retail meats. METHODS: A total of 570 strains of E. coli isolated from US retail meats in 2006 were screened for the presence of 10 QAC resistance genes [qacE, qacEΔ1, qacF, qacG, emrE, sugE(c), sugE(p), mdfA and ydgE/ydgF]. The MICs of six common disinfectants were determined using an agar dilution method. Possible associations between the presence of the gene and bacterial resistance to QACs and antimicrobials were investigated. RESULTS: emrE, sugE(c), mdfA and ydgE/ydgF were commonly present (77.2%-100%) in the E. coli isolates, but qac and sugE(p) were less prevalent (0.4%-22.3%). emrE-mdfA-sugE(c)-ydgE/F was the most common QAC resistance gene profile. A significant association was found between antimicrobial resistance and the presence of sugE(p) and qacEΔ1 (P < 0.05). Antimicrobial-resistant E. coli isolates tended to contain more diverse combinations of disinfectant resistance genes than susceptible ones. All isolates showed reduced susceptibility to five of six disinfectants compared with the control strains. Higher MICs were generally associated with the presence of qac and sugE(p) genes. CONCLUSIONS: The QAC resistance genes were commonly present among E. coli isolated from retail meats, and the qac and sugE(p) genes were highly associated with multidrug resistance phenotypes. Using QACs in the food industry may not be as effective as expected and could provide selection pressure for strains with acquired resistance to other antimicrobials.


Assuntos
Desinfetantes/farmacologia , Farmacorresistência Bacteriana/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Microbiologia de Alimentos , Carne/microbiologia , Animais , Antibacterianos/farmacologia , Escherichia coli/isolamento & purificação , Genes Bacterianos , Humanos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Estados Unidos
12.
Appl Environ Microbiol ; 80(4): 1411-20, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24334663

RESUMO

Shiga toxin-producing Escherichia coli (STEC) strains (n = 194) representing 43 serotypes and E. coli K-12 were examined for clustered regularly interspaced short palindromic repeat (CRISPR) arrays to study genetic relatedness among STEC serotypes. A subset of the strains (n = 81) was further analyzed for subtype I-E cas and virulence genes to determine a possible association of CRISPR elements with potential virulence. Four types of CRISPR arrays were identified. CRISPR1 and CRISPR2 were present in all strains tested; 1 strain also had both CRISPR3 and CRISPR4, whereas 193 strains displayed a short, combined array, CRISPR3-4. A total of 3,353 spacers were identified, representing 528 distinct spacers. The average length of a spacer was 32 bp. Approximately one-half of the spacers (54%) were unique and found mostly in strains of less common serotypes. Overall, CRISPR spacer contents correlated well with STEC serotypes, and identical arrays were shared between strains with the same H type (O26:H11, O103:H11, and O111:H11). There was no association identified between the presence of subtype I-E cas and virulence genes, but the total number of spacers had a negative correlation with potential pathogenicity (P < 0.05). Fewer spacers were found in strains that had a greater probability of causing outbreaks and disease than in those with lower virulence potential (P < 0.05). The relationship between the CRISPR-cas system and potential virulence needs to be determined on a broader scale, and the biological link will need to be established.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/patogenicidade , Fatores de Virulência/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , Genótipo , Dados de Sequência Molecular , Análise de Sequência de DNA , Sorotipagem , Escherichia coli Shiga Toxigênica/classificação
13.
Foodborne Pathog Dis ; 11(5): 342-5, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24694187

RESUMO

Non-O157 Shiga toxin-producing Escherichia coli (STEC) are increasingly recognized as foodborne pathogens worldwide. Serogroups O26, O111, and O103 cause most known outbreaks related to non-O157 STEC. Pathogenicity islands (PAIs) play a major role in the evolution of STEC pathogenicity. To determine the distribution of PAIs often associated with highly virulent STECs (OI-122, OI-43/48, OI-57, and high pathogenicity islands) among STEC O26, O103, and O111, a collection of STEC O26 (n=45), O103 (n=29), and O111 (n=52) from humans and animals were included in this study. Pulsed-field gel electrophoresis (PFGE) with XbaI digestion was used to characterize the clonal relationship of the strains. In addition, a polymerase chain reaction-restriction fragment length polymorphism assay was used to determine eae subtypes. Additional virulence genes on PAIs were identified using specific PCR assays, including OI-122: pagC, sen, efa-1, efa-2, and nleB; OI-43/48: terC, ureC, iha, and aidA-1; OI-57: nleG2-3, nleG5-2, and nleG6-2; and HPI: fyuA and irp2. A PFGE dendrogram demonstrated that instead of clustering together with strains from the same O type (O111:H8), the O111:H11 (n=14) strains clustered together with strains of the same H type (O26:H11, n=45). In addition, O26:H11 and O111:H11 strains carried eae subtype ß, whereas O111:H8 strains had eae γ2/θ. The O26:H11 and O111:H11 stains contained an incomplete OI-122 lacking pagC and a complete HPI. However, a complete OI-122 but no HPI was found in the O111:H8 strains. Additionally, aidA-1 of OI-43/48 and nleG6-2 of OI-57 were significantly associated with O26:H11 and O111:H11 strains but were almost missing in O111:H8 strains (p<0.001). This study demonstrated that H11 (O111:H11 and O26:H11) strains were closely related and may have come from the same ancestor.


Assuntos
Ilhas Genômicas , Escherichia coli Shiga Toxigênica/classificação , Adesinas Bacterianas/genética , Adesinas de Escherichia coli/genética , Animais , Técnicas de Tipagem Bacteriana , Eletroforese em Gel de Campo Pulsado , Proteínas de Escherichia coli/genética , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Toxina Shiga/genética , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/isolamento & purificação , Fatores de Virulência/genética
14.
Foodborne Pathog Dis ; 11(10): 798-807, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25188010

RESUMO

Salmonella enterica subspecies enterica serotype Newport is one of the common serotypes causing foodborne salmonellosis outbreaks in the United States. Salmonella Newport consists of three lineages exhibiting extensive genetic diversity. Due to the importance of Salmonella pathogenicity islands 5 and 6 (SPI-5 and SPI-6) in virulence of pathogenic Salmonella, the genetic diversity of these two SPIs may relate to different potentials of Salmonella Newport pathogenicity. Most Salmonella Newport strains from North America belong to Salmonella Newport lineages II and III. A total 28 Salmonella Newport strains of lineages II and III from diverse sources and geographic locations were analyzed, and 11 additional Salmonella genomes were used as outgroup in phylogenetic analyses. SPI-5 was identified in all Salmonella Newport strains and 146 single nucleotide polymorphisms (SNPs) were detected. Thirty-nine lineage-defining SNPs were identified, including 18 nonsynonymous SNPs. Two 40-kb genomic islands (SPI5-GI1 and SPI5-GI2) encoding bacteriophage genes were found between tRNA-ser and pipA. SPI5-GI1 was only present in Salmonella Newport multidrug-resistant strains of lineage II. SPI-6 was found in all strains but three Asian strains in Salmonella Newport lineage II, whereas the three Asian strains carried genomic island SPI6-GI1 at the same locus as SPI-6 in other Salmonella. SPI-6 exhibited 937 SNPs, and phylogenetic analysis demonstrated that clustering of Salmonella Newport isolates was a reflection of their geographic origins. The sequence diversity within SPI-5 and SPI-6 suggests possible recombination events and different virulence potentials of Salmonella Newport. The SNPs could be used as biomarkers during epidemiological investigations.


Assuntos
Ilhas Genômicas , Polimorfismo de Nucleotídeo Único , Salmonella/genética , Filogenia , Salmonella/classificação , Alinhamento de Sequência , Análise de Sequência de DNA
15.
Stem Cell Res Ther ; 15(1): 3, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167106

RESUMO

Diabetes mellitus (DM) is a serious chronic metabolic disease that can lead to many serious complications, such as cardiovascular disease, retinopathy, neuropathy, and kidney disease. Once diagnosed with diabetes, patients need to take oral hypoglycemic drugs or use insulin to control blood sugar and slow down the progression of the disease. This has a significant impact on the daily life of patients, requiring constant monitoring of the side effects of medication. It also imposes a heavy financial burden on individuals, their families, and even society as a whole. Adipose-derived stem cells (ADSCs) have recently become an emerging therapeutic modality for DM and its complications. ADSCs can improve insulin sensitivity and enhance insulin secretion through various pathways, thereby alleviating diabetes and its complications. Additionally, ADSCs can promote tissue regeneration, inhibit inflammatory reactions, and reduce tissue damage and cell apoptosis. The potential mechanisms of ADSC therapy for DM and its complications are numerous, and its extensive regenerative and differentiation ability, as well as its role in regulating the immune system and metabolic function, make it a powerful tool in the treatment of DM. Although this technology is still in the early stages, many studies have already proven its safety and effectiveness, providing new treatment options for patients with DM or its complications. Although based on current research, ADSCs have achieved some results in animal experiments and clinical trials for the treatment of DM, further clinical trials are still needed before they can be applied in a clinical setting.


Assuntos
Diabetes Mellitus Experimental , Animais , Humanos , Diabetes Mellitus Experimental/metabolismo , Tecido Adiposo , Adipócitos/metabolismo , Glicemia/metabolismo , Células-Tronco/metabolismo
16.
Cell Death Discov ; 10(1): 53, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38278820

RESUMO

Pathological cardiac hypertrophy is an independent risk factor for heart failure. Disruption of mitochondrial protein homeostasis plays a key role in pathological cardiac hypertrophy; however, the mechanism of maintaining mitochondrial homeostasis in pathological cardiac hypertrophy remains unclear. In this study, we investigated the regulatory mechanisms of mitochondrial protein homeostasis in pathological cardiac hypertrophy. Wildtype (WT) mice, knockout mice, and mice transfected with lentivirus overexpressing mouse C1q-tumor necrosis factor-related protein-3 (CTRP3) underwent transverse aortic constriction or sham surgery. After 4 weeks, cardiac function, mitochondrial function, and oxidative stress injury were examined. For mechanistic studies, neonatal rat cardiomyocytes were treated with small interfering RNA or overexpression plasmids for the relevant genes. CTRP3 overexpression attenuated transverse aortic constriction (TAC) induced pathological cardiac hypertrophy, mitochondrial dysfunction, and oxidative stress injury compared to that in WT mice. TAC or Ang II resulted in compensatory activation of UPRmt, but this was not sufficient to counteract pathologic cardiac hypertrophy. CTRP3 overexpression further induced activation of UPRmt during pathologic cardiac hypertrophy and thereby alleviated pathologic cardiac hypertrophy, whereas CTRP3 knockout or knockdown inhibited UPRmt. ATF5 was a key regulatory molecule of UPRmt, as ATF5 knockout prevented the cardioprotective effect of CTRP3 in TAC mice. In vitro, SIRT1 was identified as a possible downstream CTRP3 effector molecule, and SIRT1 knockout blocked the cardioprotective effects of CTRP3. Our results also suggest that ATF5 may be regulated by SIRT1. Our study demonstrates that CTRP3 activates UPRmt via the SIRT1/ATF5 axis under pathological myocardial hypertrophy, thus attenuating mitochondrial dysfunction and oxidative stress injury.

17.
Biomed Pharmacother ; 158: 114100, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36538860

RESUMO

Myocardial ischemia-reperfusion (MI/R) is a major risk factor for cardiovascular disease. At present, reducing oxidative stress and apoptosis is a crucial therapeutic strategy for ameliorating MI/R injury. However, there is a lack of drugs targeting oxidative stress and apoptosis for the clinical therapy of MI/R. Bergenin is a reportedly effective agent with antioxidative and antiapoptotic activity against acute injury. Nevertheless, the roles and potential mechanisms of bergenin against MI/R injury remain unknown. Here, we hypothesized that bergenin attenuated MI/R-induced apoptosis and reactive oxygen species (ROS) production via SIRT1. Mice were subjected to MI/R and treated with bergenin, after which the cardiac function, cardiomyocyte apoptosis, LDH release, and MDA content were evaluated. In vitro, myocardial injury model of H9c2 cells was induced by simulated ischemia/reperfusion (SI/R), apoptosis and oxidative stress was decreased after treated with bergenin. Bergenin significantly reduced myocardial apoptosis and ROS generation in vitro and improved cardiac function in vivo. Intriguingly, bergenin remarkably decreased apoptosis in cardiac tissue accompanied by SIRT1 upregulation following MI/R injury. Further studies showed that inhibiting SIRT1 blocked bergenin's beneficial impact against apoptosis following SI/R injury through excessive oxidative stress and depression of the Bcl2 to Bax ratio. Collectively, these findings indicate that bergenin alleviates MI/R injury by ameliorating myocardial apoptosis and oxidative damage via the SIRT1 signaling pathway.


Assuntos
Traumatismo por Reperfusão Miocárdica , Camundongos , Animais , Traumatismo por Reperfusão Miocárdica/metabolismo , Sirtuína 1/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Apoptose , Estresse Oxidativo , Miócitos Cardíacos
18.
Sci Rep ; 13(1): 1331, 2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36693882

RESUMO

Multidrug-resistant (MDR) Salmonella has been a long-standing challenge in public health and food safety. The prevalence of MDR S. Enteritidis, especially isolated from humans, in China is significantly higher than those from the U.S. and other countries. A dataset of 197 S. Enteritidis genomes, including 16 sequenced clinical isolates from China and 181 downloaded genomes of human isolates from the U.S., Europe, and Africa, was analyzed for genomic diversity, virulence potential, and antimicrobial resistance (AMR). Phylogenomic analyses identified four major well-supported clades (I-IV). While AMR genotype in the majority of isolates in clades I and IV displayed as pan-susceptible, 81.8% (9/11) and 22.4% (13/58) of isolates in clades III and II were MDR, respectively. It is noted that 77% (10/13) of MDR isolates in clade II were from China. The most common antimicrobial resistance genes (ARGs) carried by the Chinese isolates were aph(3')-IIa, blaCTX-M-55, and blaTEM-1B, whereas blaTEM-1B, sul1, sul2, drfA7, aph(3")-Ib/strA, and aph(6)-Id/strB were most often identified in those from Africa (clade III). Among the 14 plasmid types identified, IncX1 and IncFII(pHN7A8) were found exclusively in the Chinese MDR isolates, while IncQ1 was highly associated with the African MDR isolates. The spvRABCD virulence operon was present in 94.9% (187/197) of isolates tested and was highly associated with both the IncF (IncFII and IncFIB) plasmids. In addition, phylogenetic differences in distribution of Salmonella pathogenicity islands (SPIs), prophages and other accessory genes were also noted. Taken together, these findings provide new insights into the molecular mechanisms underpinning diversification of MDR S. Enteritidis.


Assuntos
Salmonella enterica , Salmonella enteritidis , Humanos , Antibacterianos/farmacologia , Filogenia , Farmacorresistência Bacteriana/genética , Genômica , Geografia , Farmacorresistência Bacteriana Múltipla/genética , Salmonella enterica/genética , Testes de Sensibilidade Microbiana
19.
Biomed Pharmacother ; 161: 114324, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36958192

RESUMO

Gastrodia elata exhibits extensive pharmacological activity; its extract gastrodin (GAS) has been used clinically to treat cardiovascular diseases. In the present study, we examined the effect of GAS in a mice model of pathological cardiac hypertrophy, which was induced using transverse aortic constriction (TAC). Male C57BL/6 J mice underwent either TAC or sham surgery. GAS was administered post-surgically for 6 weeks and significantly improved the deterioration of cardiac contractile function caused by pressure overload, cardiac hypertrophy, and fibrosis in mice. Treatment with GAS for 6 weeks upregulated myosin heavy chain α and down-regulated myosin heavy chain ß and atrial natriuretic peptide, while insulin increased the effects of GAS against cardiac hypertrophy. In vitro studies showed that GAS could also protect phenylephrine-induced cardiomyocyte hypertrophy, and these effects were attenuated by BAY-876, and increased by insulin. Taken together, our results suggest that the anti-hypertrophic effect of gastrodin depends on its entry into cardiomyocytes through GLUT4.


Assuntos
Insulinas , Cadeias Pesadas de Miosina , Animais , Masculino , Camundongos , Cardiomegalia/tratamento farmacológico , Modelos Animais de Doenças , Insulinas/farmacologia , Insulinas/uso terapêutico , Camundongos Endogâmicos C57BL , Miócitos Cardíacos , Transportador de Glucose Tipo 4/metabolismo
20.
J Bacteriol ; 194(18): 5146, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22933769

RESUMO

Salmonellosis is a major contributor to the global public health burden. Salmonella enterica serotype Newport has ranked among three Salmonella serotypes most commonly associated with food-borne outbreaks in the United States. It was thought to be polyphyletic and composed of independent lineages. Here we report draft genomes of eight strains of S. Newport from diverse hosts and locations.


Assuntos
DNA Bacteriano/química , DNA Bacteriano/genética , Genoma Bacteriano , Salmonella enterica/genética , Análise de Sequência de DNA , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/microbiologia , Dados de Sequência Molecular , Infecções por Salmonella/epidemiologia , Infecções por Salmonella/microbiologia , Salmonella enterica/isolamento & purificação , Estados Unidos/epidemiologia
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