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1.
Small ; : e2400292, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38659378

RESUMO

Aqueous Zn batteries employing mildly acidic electrolytes have emerged as promising contenders for safe and cost-effective energy storage solutions. Nevertheless, the intrinsic reversibility of the Zn anode becomes a focal concern due to the involvement of acidic electrolyte, which triggers Zn corrosion and facilitates the deposition of insulating byproducts. Moreover, the unregulated growth of Zn over cycling amplifies the risk of internal short-circuiting, primarily induced by the formation of Zn dendrites. In this study, a class of glucose-derived monomers and a block copolymer are synthesized through a building-block assembly strategy, ultimately leading to uncover the optimal polymer structure that suppresses the Zn corrosion while allowing efficient ion conduction with a substantial contribution from cation transport. Leveraging these advancements, remarkable enhancements are achieved in the realm of Zn reversibility, exemplified by a spectrum of performance metrics, including robust cycling stability without voltage overshoot and short-circuiting during 3000 h of cycling, stable operation at a high depth of charge/discharge of 75% and a high current density, >95% Coulombic efficiency over 2000 cycles, successful translation of the anode improvement to full cell performance. These polymer designs offer a transformative path based on the modular synthesis of polymeric coatings toward highly reversible Zn anode.

2.
Pediatr Cardiol ; 45(1): 68-80, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37741935

RESUMO

Delirium is a common postoperative complication in children with congenital heart disease, which affects their postoperative recovery. The purpose of this study is to explore the risk factors of delirium and construct a nomogram model to provide novel references for the prevention and management of postoperative delirium in children with congenital heart disease. 470 children after congenital heart surgery treated in the cardiac intensive care unit (CICU) of Shanghai Children's Medical Center were divided into a model and a validation cohort according to the principle of 7:3 distribution temporally. Then, the delirium-related influencing factors of 330 children in the training cohort were analyzed, and the nomogram model was established by a combination of Lasso regression and logistic regression. The data of 140 children in the validation cohort were used to verify the effectiveness of the model. Multivariable logistic regression analysis showed that age, disease severity, non-invasive ventilation after extubation, delayed chest closure, phenobarbital dosage, promethazine dosage, mannitol usage, and elevated temperature were independent risk factors for postoperative delirium. The area under the receiver operating characteristic curve (AUC) of the nomogram model was 0.864 and the Brier value was 0.121. Regarding the validation of the model's effect, our results showed that 51 cases were predicted by the model and 34 cases actually occurred, including 4 cases of false negative and 21 cases of false positive. The positive predictive value of the model was 58.8%, and its negative predictive value was 95.5%. The nomogram model established in this study showed acceptable performance in predicting postoperative delirium in children with congenital heart disease.


Assuntos
Delírio do Despertar , Cardiopatias Congênitas , Criança , Humanos , Estudos Prospectivos , Nomogramas , China/epidemiologia , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/cirurgia , Fatores de Risco , Estudos Retrospectivos
3.
Small ; 19(26): e2300230, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36938705

RESUMO

As intelligent microsystems develop, many revolutionary applications, such as the swallowing surgeon proposed by Richard Feynman, are about to evolve. Nonetheless, integrable energy storage satisfying the demand for autonomous operations has emerged as a major obstacle to the deployment of intelligent microsystems. A reason for the lagging development of integrable batteries is the challenge of miniaturization through microfabrication procedures. Lithium batteries, generated by the most successful battery chemistry, are not stable in the air, thus creating major manufacturing challenges. Other cations (Na+ , Mg2+ , Al3+ , K+ ) are still in the early stages of development. In contrast, the superior stability of zinc batteries in the air brings high compatibility to microfabrication protocols and has already demonstrated excellent practicability in full-sized devices. To obtain energy-dense and high-power zinc microbatteries within square-millimeter or smaller footprints, sandwich, pillar, and Swiss-roll configurations are developed. Thin interdigital and fiber microbatteries find their applications being integrated into wearable devices and electronic skin. It is foreseeable that zinc microbatteries will find their way into highly integrated microsystems unlocking their full potential for autonomous operation. This review summarizes the material development, configuration innovation, and application-oriented integration of zinc microbatteries.

4.
Planta ; 257(4): 74, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36879182

RESUMO

MAIN CONCLUSION: The alpine meadow plants showed great intra- and inter-genera variations of chemical profiles of cuticular waxes. Developing an understanding of wax structure-function relationships that will help us tackle global climate change requires a detailed understanding of plant wax chemistry. The goal in this study was to provide a catalog of wax structures, abundances, and compositions on alpine meadow plants. Here, leaf waxes from 33 plant species belonging to 11 families were sampled from alpine meadows of the east side of the Qinghai-Tibet Plateau. Across these species, total wax coverage varied from 2.30 µg cm-2 to 40.70 µg cm-2, showing variation both within as well as between genera and suggesting that wax variation is subject to both environmental and genetic effects. Across all wax samples, more than 140 wax compounds belonging to 13 wax compound classes were identified, including both ubiquitous wax compounds and lineage-specific compounds. Among the ubiquitous compounds (primary alcohols, alkyl esters, aldehydes, alkanes, and fatty acids), chain length profiles across a wide range of species point to key differences in the chain length specificity of alcohol and alkane formation machinery. The lineage-specific wax compound classes (diols, secondary alcohols, lactones, iso-alkanes, alkyl resorcinols, phenylethyl esters, cinnamate esters, alkyl benzoates, and triterpenoids) nearly all consisted of isomers with varying chain lengths or functional group positions, making the diversity of specialized wax compounds immense. The comparison of species relationships between chemical data and genetic data highlighted the importance of inferring phylogenetic relationships from data sets that contain a large number of variables that do not respond to environmental stimuli.


Assuntos
Aldeídos , Pradaria , Filogenia , Tibet , Alcanos , Ésteres
5.
Int J Med Microbiol ; 313(2): 151575, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36736015

RESUMO

We aimed to investigate whether a selective pre-PCR enrichment step improves test performance of RIDA®GENE EHEC/EPEC to detect diarrheagenic Escherichia coli from stool samples. Each of the 250 stool samples was analyzed for the presence of stx1/2 and eae both with and without pre-PCR enrichment in selective broth. In comparison to a reference method, sensitivities for stx1/2 and eae with and without pre-PCR enrichment were 84% (95%CI 70-93) and 89% (stx1/2, 95%CI 76-96), and 71% (95%CI 58-81) and 72% (eae, 95%CI 60-82), respectively. Specificity exceeded 97% for both methods and target genes. In summary, pre-PCR broth enrichment did not improve test performance.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Scrapie , Animais , Ovinos/genética , Humanos , Infecções por Escherichia coli/diagnóstico , Proteínas de Escherichia coli/genética , Fezes , Escherichia coli/genética , Reação em Cadeia da Polimerase/métodos , Diarreia/diagnóstico
6.
Nanotechnology ; 32(19): 195407, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-33535192

RESUMO

Tin and its oxides are promising anode materials owing to their high theoretical capacity, rich resource, and environmental benignity. To achieve low cost and green synthesis, a facile synthetic route of SnO x /graphene composites is proposed, using a simple galvanic replacement method to quickly obtain abundant foamed tin as raw material and ball milling method to realize a mechanochemical reaction between SnO x (0 ≤ x ≤ 2) and graphene. Under different annealing conditions, the foamed tin is converted to tin oxides with multiple oxidation states (Sn3O4, SnO, and SnO2). These unique components can greatly affect the electrochemical performance of the electrode in LIBs. The as-prepared electrode (SnO x -300/G) obtained by annealing foamed tin at 300 °C for 4 h and combining SnO x powders with graphene via ball milling shows great cycling stability, retaining a high capacity of 786 mA h g-1 at 0.1 A g-1 after 150 cycles, and its initial Coulombic efficiency can reach 84.03%. Thus, this facile synthesis can provide an environmentally friendly route for commercial production of high-performance energy storage materials.

7.
Environ Dev Sustain ; 23(12): 18509-18539, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33942012

RESUMO

ABSTRACT: Lae City (LC) of Morobe Province is the second-largest city in Papua New Guinea. Due to the abundant natural resources it inherits, the resultant urbanization has led to an influx of the human population. This increase in population as a result of industrialization has led to increased municipal solid waste (MSW) accumulation. To address this exigent issue, which affects the nation's carbon footprint, it is imperative to review socio-economic and geographic factors to establish a feasible approach for managing MSW efficiently and sustainably. In the quest to achieve the same, the present assessment focuses on the 3 core waste management hierarchy systems to support sustainable development for LC by reviewing existing opportunities and challenges associated with the current MSW management system and the associated policies. The result shows that as a sustainable approach to MSW management of LC, a zero-waste campaign for resource recovery engaging all stakeholders can be implemented since the organic content of MSW generated in LC is as high as 70%. Moreover, the dumping of MSW at the dedicated dumpsite site can be minimized if policies are strengthened and the proposed waste avoidance pathway is implemented strictly. In addition to this, to avoid the contamination of groundwater and recovery of methane, the use of the Fukuoka approach in the existing landfills has been suggested to capture leachate without any huge expenditure.

8.
PLoS Pathog ; 13(2): e1006159, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28158302

RESUMO

Outer membrane vesicles (OMVs) are important tools in bacterial virulence but their role in the pathogenesis of infections caused by enterohemorrhagic Escherichia coli (EHEC) O157, the leading cause of life-threatening hemolytic uremic syndrome, is poorly understood. Using proteomics, electron and confocal laser scanning microscopy, immunoblotting, and bioassays, we investigated OMVs secreted by EHEC O157 clinical isolates for virulence factors cargoes, interactions with pathogenetically relevant human cells, and mechanisms of cell injury. We demonstrate that O157 OMVs carry a cocktail of key virulence factors of EHEC O157 including Shiga toxin 2a (Stx2a), cytolethal distending toxin V (CdtV), EHEC hemolysin, and flagellin. The toxins are internalized by cells via dynamin-dependent endocytosis of OMVs and differentially separate from vesicles during intracellular trafficking. Stx2a and CdtV-B, the DNase-like CdtV subunit, separate from OMVs in early endosomes. Stx2a is trafficked, in association with its receptor globotriaosylceramide within detergent-resistant membranes, to the Golgi complex and the endoplasmic reticulum from where the catalytic Stx2a A1 fragment is translocated to the cytosol. CdtV-B is, after its retrograde transport to the endoplasmic reticulum, translocated to the nucleus to reach DNA. CdtV-A and CdtV-C subunits remain OMV-associated and are sorted with OMVs to lysosomes. EHEC hemolysin separates from OMVs in lysosomes and targets mitochondria. The OMV-delivered CdtV-B causes cellular DNA damage, which activates DNA damage responses leading to G2 cell cycle arrest. The arrested cells ultimately die of apoptosis induced by Stx2a and CdtV via caspase-9 activation. By demonstrating that naturally secreted EHEC O157 OMVs carry and deliver into cells a cocktail of biologically active virulence factors, thereby causing cell death, and by performing first comprehensive analysis of intracellular trafficking of OMVs and OMV-delivered virulence factors, we provide new insights into the pathogenesis of EHEC O157 infections. Our data have implications for considering O157 OMVs as vaccine candidates.


Assuntos
Proteínas da Membrana Bacteriana Externa/metabolismo , Infecções por Escherichia coli/metabolismo , Interações Hospedeiro-Patógeno/fisiologia , Fatores de Virulência/metabolismo , Virulência/fisiologia , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Escherichia coli O157 , Humanos , Immunoblotting , Microscopia Eletrônica de Transmissão , Transporte Proteico/fisiologia , Vesículas Transportadoras/fisiologia
9.
Appl Environ Microbiol ; 83(23)2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28970221

RESUMO

Sorbitol-fermenting (SF) enterohemorrhagic Escherichia coli (EHEC) O157:H- strains, first identified in Germany, have emerged as important pathogens throughout Europe. Besides chromosomally encoded Shiga toxin 2a (the major virulence factor), several putative virulence loci, including the hly, etp, and sfp operons, encoding EHEC hemolysin, type II secretion system proteins, and Sfp fimbriae, respectively, are located on the 121-kb plasmid pSFO157 in German strains. Here we report novel SF EHEC O157:H- strains isolated from patients in the Czech Republic. These strains share the core genomes and chromosomal virulence loci encoding toxins (stx2a and the cdtV-ABC operon) and adhesins (eae-γ, efa1, lpfAO157OI-141, and lpfAO157OI-154) with German strains but differ essentially in their plasmids. In contrast to all previously detected SF EHEC O157:H- strains, the Czech strains carry two plasmids, of 79 kb and 86 kb. The 79-kb plasmid harbors the sfp operon, but neither of the plasmids contains the hly and etp operons. Sequence analyses demonstrated that the 79-kb plasmid (pSFO157 258/98-1) evolved from pSFO157 of German strains by deletion of a 41,534-bp region via homologous recombination, resulting in loss of the hly and etp operons. The 86-kb plasmid (pSFO157 258/98-2) displays 98% sequence similarity to a 92.7-kb plasmid of an extraintestinal pathogenic E. coli bloodstream isolate. Our finding of this novel plasmid composition in SF EHEC O157:H- strains extends the evolutionary history of EHEC O157 plasmids. Moreover, the unique molecular plasmid characteristics permit the identification of such strains, thereby facilitating further investigations of their geographic distribution, clinical significance, and epidemiology.IMPORTANCE Since their first identification in Germany in 1989, sorbitol-fermenting enterohemorrhagic Escherichia coli O157:H- (nonmotile) strains have emerged as important causes of the life-threatening disease hemolytic-uremic syndrome in Europe. They account for 10 to 20% of sporadic cases of this disease and have caused several large outbreaks. The strains isolated throughout Europe share conserved chromosomal and plasmid characteristics. Here we identified novel sorbitol-fermenting enterohemorrhagic E. coli O157:H- patient isolates in the Czech Republic which differ from all such strains reported previously by their unique plasmid characteristics, including plasmid number, composition of plasmid-carried virulence genes, and plasmid origins. Our findings contribute substantially to understanding the evolution of E. coli O157 strains and their plasmids. In practical terms, they enable the identification of strains with these novel plasmid characteristics in patient stool samples and thus the investigation of their roles as human pathogens in other geographic areas.


Assuntos
Infecções por Escherichia coli/microbiologia , Escherichia coli O157/isolamento & purificação , Plasmídeos/genética , Sorbitol/metabolismo , República Tcheca , Escherichia coli O157/classificação , Escherichia coli O157/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fermentação , Alemanha , Humanos , Plasmídeos/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
10.
J Clin Microbiol ; 54(5): 1357-63, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26984976

RESUMO

Alongside the well-characterized enterohemorrhagic Escherichia coli (EHEC) O157:H7, serogroup O157 comprises sorbitol-fermenting typical and atypical enteropathogenic E. coli (EPEC/aEPEC) strains that carry the intimin-encoding gene eae but not Shiga toxin-encoding genes (stx). Since little is known about these pathogens, we characterized 30 clinical isolates from patients with hemolytic uremic syndrome (HUS) or uncomplicated diarrhea with respect to their flagellin gene (fliC) type and multilocus sequence type (MLST). Moreover, we applied whole-genome sequencing (WGS) to determine the phylogenetic relationship with other eae-positive EHEC serotypes and the composition of the rfbO157 region. fliC typing resulted in five fliC types (H7, H16, H34, H39, and H45). Isolates of each fliC type shared a unique ST. In comparison to the 42 HUS-associated E. coli (HUSEC) strains, only the stx-negative isolates with fliCH7 shared their ST with EHEC O157:H7/H(-) strains. With the exception of one O157:H(-) fliCH16 isolate, HUS was exclusively associated with fliCH7. WGS corroborated the separation of the fliCH7 isolates, which were closely related to the EHEC O157:H7/H(-) isolates, and the diverse group of isolates exhibiting different fliC types, indicating independent evolution of the different serotypes. This was also supported by the heterogeneity within the rfbO157 region that exhibited extensive recombinations. The genotypic subtypes and distribution of clinical symptoms suggested that the stx-negative O157 strains with fliCH7 were originally EHEC strains that lost stx The remaining isolates form a distinct and diverse group of atypical EPEC isolates that do not possess the full spectrum of virulence genes, underlining the importance of identifying the H antigen for clinical risk assessment.


Assuntos
Escherichia coli Enteropatogênica/classificação , Escherichia coli Enteropatogênica/metabolismo , Escherichia coli O157/classificação , Escherichia coli O157/metabolismo , Variação Genética , Filogenia , Sorbitol/metabolismo , Diarreia/microbiologia , Escherichia coli Enteropatogênica/genética , Escherichia coli Enteropatogênica/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Escherichia coli O157/genética , Escherichia coli O157/isolamento & purificação , Proteínas de Escherichia coli/genética , Fermentação , Genoma Bacteriano , Síndrome Hemolítico-Urêmica/microbiologia , Humanos , Tipagem Molecular , Análise de Sequência de DNA
11.
PLoS Pathog ; 9(12): e1003797, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24348251

RESUMO

Enterohemorrhagic Escherichia coli (EHEC) strains cause diarrhea and hemolytic uremic syndrome resulting from toxin-mediated microvascular endothelial injury. EHEC hemolysin (EHEC-Hly), a member of the RTX (repeats-in-toxin) family, is an EHEC virulence factor of increasingly recognized importance. The toxin exists as free EHEC-Hly and as EHEC-Hly associated with outer membrane vesicles (OMVs) released by EHEC during growth. Whereas the free toxin is lytic towards human endothelium, the biological effects of the OMV-associated EHEC-Hly on microvascular endothelial and intestinal epithelial cells, which are the major targets during EHEC infection, are unknown. Using microscopic, biochemical, flow cytometry and functional analyses of human brain microvascular endothelial cells (HBMEC) and Caco-2 cells we demonstrate that OMV-associated EHEC-Hly does not lyse the target cells but triggers their apoptosis. The OMV-associated toxin is internalized by HBMEC and Caco-2 cells via dynamin-dependent endocytosis of OMVs and trafficked with OMVs into endo-lysosomal compartments. Upon endosome acidification and subsequent pH drop, EHEC-Hly is separated from OMVs, escapes from the lysosomes, most probably via its pore-forming activity, and targets mitochondria. This results in decrease of the mitochondrial transmembrane potential and translocation of cytochrome c to the cytosol, indicating EHEC-Hly-mediated permeabilization of the mitochondrial membranes. Subsequent activation of caspase-9 and caspase-3 leads to apoptotic cell death as evidenced by DNA fragmentation and chromatin condensation in the intoxicated cells. The ability of OMV-associated EHEC-Hly to trigger the mitochondrial apoptotic pathway in human microvascular endothelial and intestinal epithelial cells indicates a novel mechanism of EHEC-Hly involvement in the pathogenesis of EHEC diseases. The OMV-mediated intracellular delivery represents a newly recognized mechanism for a bacterial toxin to enter host cells in order to target mitochondria.


Assuntos
Células Endoteliais/microbiologia , Escherichia coli Êntero-Hemorrágica/patogenicidade , Proteínas Hemolisinas/metabolismo , Síndrome Hemolítico-Urêmica/microbiologia , Mitocôndrias/microbiologia , Vesículas Secretórias/metabolismo , Fatores de Virulência/metabolismo , Apoptose/efeitos dos fármacos , Células CACO-2 , Membrana Celular/metabolismo , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/fisiologia , Escherichia coli Êntero-Hemorrágica/genética , Escherichia coli Êntero-Hemorrágica/ultraestrutura , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacologia , Síndrome Hemolítico-Urêmica/genética , Síndrome Hemolítico-Urêmica/metabolismo , Humanos , Mitocôndrias/efeitos dos fármacos , Dados de Sequência Molecular , Fatores de Virulência/genética , Fatores de Virulência/farmacologia
12.
Infect Immun ; 82(11): 4631-42, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25156739

RESUMO

Enterohemorrhagic Escherichia coli (EHEC), a subgroup of Shiga toxin (Stx)-producing E. coli (STEC), is a leading cause of diarrhea and hemolytic-uremic syndrome (HUS) in humans. However, urinary tract infections (UTIs) caused by this microorganism but not associated with diarrhea have occasionally been reported. We geno- and phenotypically characterized three EHEC isolates obtained from the urine of hospitalized patients suffering from UTIs. These isolates carried typical EHEC virulence markers and belonged to HUS-associated E. coli (HUSEC) clones, but they lacked virulence markers typical of uropathogenic E. coli. One isolate exhibited a localized adherence (LA)-like pattern on T24 urinary bladder epithelial cells. Since the glycosphingolipids (GSLs) globotriaosylceramide (Gb3Cer) and globotetraosylceramide (Gb4Cer) are well-known receptors for Stx but also for P fimbriae, a major virulence factor of extraintestinal pathogenic E. coli (ExPEC), the expression of Gb3Cer and Gb4Cer by T24 cells and in murine urinary bladder tissue was examined by thin-layer chromatography and mass spectrometry. We provide data indicating that Stxs released by the EHEC isolates bind to Gb3Cer and Gb4Cer isolated from T24 cells, which were susceptible to Stx. All three EHEC isolates expressed stx genes upon growth in urine. Two strains were able to cause UTI in a murine infection model and could not be outcompeted in urine in vitro by typical uropathogenic E. coli isolates. Our results indicate that despite the lack of ExPEC virulence markers, EHEC variants may exhibit in certain suitable hosts, e.g., in hospital patients, a uropathogenic potential. The contribution of EHEC virulence factors to uropathogenesis remains to be further investigated.


Assuntos
Cistite/microbiologia , Escherichia coli Êntero-Hemorrágica/isolamento & purificação , Escherichia coli Êntero-Hemorrágica/metabolismo , Infecções por Escherichia coli/microbiologia , Infecções Urinárias/microbiologia , Adulto , Idoso , Animais , Linhagem Celular , Escherichia coli Êntero-Hemorrágica/genética , Escherichia coli Êntero-Hemorrágica/patogenicidade , Feminino , Humanos , Camundongos , Adulto Jovem
13.
Environ Microbiol ; 16(4): 963-76, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24034719

RESUMO

Shiga toxin (Stx)-producing Escherichia coli (STEC) of serogroup O174 are human pathogenic intimin gene (eae)-negative STEC. To facilitate diagnosis and subtyping, we genotypically and phenotypically characterized 25 STEC O174 isolates from humans with different clinical outcomes and from animals and the environment. fliC genotyping resulted in four different genotypes (fliCH2 : n = 5; fliCH8 : n = 8; fliCH21 : n = 11; fliCH46 : n = 1). Twenty-three strains were motile expressing the corresponding H antigen; two non-motile isolates possessed fliCH8 . The stx genotypes and non-stx virulence loci, including toxins, serine-proteases and adhesins correlated well with serotypes but showed no differences with respect to the isolates' origins. Multilocus sequence typing identified seven sequence types that correlated with serotypes. Core gene typing further specified the four serotypes, including a previously unknown O174:H46 combination, and revealed distant relationships of the different serotypes within serogroup O174 and in relation to other haemolytic uremic syndrome (HUS)-associated STEC. Only serotype O174:H21 was associated with HUS. Differences in virulence factors and in the adherence capacity of STEC O174 corroborated this separation into four distinct groups. Our study provides a basis for O174 subtyping, unravels considerable genotypic and phenotypic heterogeneity and sheds light to potential environmental and animal reservoirs.


Assuntos
Proteínas de Escherichia coli/genética , Toxina Shiga/genética , Escherichia coli Shiga Toxigênica/fisiologia , Animais , Antibacterianos/farmacologia , Aderência Bacteriana , Bovinos , Linhagem Celular , Chlorocebus aethiops , Farmacorresistência Bacteriana Múltipla , Proteínas de Escherichia coli/toxicidade , Genótipo , Humanos , Mucosa Intestinal/microbiologia , Dados de Sequência Molecular , Tipagem de Sequências Multilocus , Fenótipo , Filogenia , Toxina Shiga/toxicidade , Escherichia coli Shiga Toxigênica/efeitos dos fármacos , Escherichia coli Shiga Toxigênica/isolamento & purificação , Células Vero
15.
Adv Exp Med Biol ; 801: 213-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24664701

RESUMO

Variations in several complement genes are now known to be significant risk factors for the development of age-related macular degeneration (AMD). Despite dramatic effects on disease susceptibility, the underlying mechanisms by which common polymorphisms in complement proteins alter disease risk have remained unclear. Genetically modified mice in which the activity of the complement has been altered are available and can be used to investigate the role of complement in the pathogenesis of AMD. In this mini review, we will discuss some existing complement models of AMD and our efforts to develop and characterize the ocular phenotype in a variety of mice in which complement is either chronically activated or inhibited. A spectrum of complement dysregulation was modeled on the APOE4 AMD mouse model by crossing these mice to complement factor H knockout (cfh-/-) mice to test the impact of excess complement activation, and by crossing them to soluble-complement-receptor-1-related protein y (sCrry) mice, in which sCrry acts as a potent inhibitor of mouse complement acting in a manner similar to CFH. In addition, we have also generated humanized CFH mice expressing normal and risk variants of CFH.


Assuntos
Fator H do Complemento/deficiência , Fator H do Complemento/imunologia , Proteínas do Sistema Complemento/imunologia , Nefropatias/imunologia , Degeneração Macular/imunologia , Animais , Fator H do Complemento/genética , Modelos Animais de Doenças , Doenças da Deficiência Hereditária de Complemento , Humanos , Camundongos , Camundongos Knockout
16.
Chin J Integr Med ; 30(3): 277-288, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38057549

RESUMO

As a serious cardiovascular disease, atherosclerosis (AS) causes chronic inflammation and oxidative stress in the body and poses a threat to human health. Lipoprotein-associated phospholipase A2 (Lp-PLA2) is a member of the phospholipase A2 (PLA2) family, and its elevated levels have been shown to contribute to AS. Lp-PLA2 is closely related to a variety of lipoproteins, and its role in promoting inflammatory responses and oxidative stress in AS is mainly achieved by hydrolyzing oxidized phosphatidylcholine (oxPC) to produce lysophosphatidylcholine (lysoPC). Moreover, macrophage apoptosis within plaque is promoted by localized Lp-PLA2 which also promotes plaque instability. This paper reviews those researches of Chinese medicine in treating AS via reducing Lp-PLA2 levels to guide future experimental studies and clinical applications related to AS.


Assuntos
Aterosclerose , Placa Aterosclerótica , Humanos , 1-Alquil-2-acetilglicerofosfocolina Esterase , Medicina Tradicional Chinesa , Aterosclerose/tratamento farmacológico , Lipoproteínas , Biomarcadores
17.
Microbiol Res ; 282: 127667, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38442456

RESUMO

The interaction of iron and intestinal flora, both of which play crucial roles in many physiologic processes, is involved in the development of Metabolic syndrome (MetS). MetS is a pathologic condition represented by insulin resistance, obesity, dyslipidemia, and hypertension. MetS-related comorbidities including type 2 diabetes mellitus (T2DM), obesity, metabolism-related fatty liver (MAFLD), hypertension polycystic ovary syndrome (PCOS), and so forth. In this review, we examine the interplay between intestinal flora and human iron metabolism and its underlying mechanism in the pathogenesis of MetS-related comorbidities. The composition and metabolites of intestinal flora regulate the level of human iron by modulating intestinal iron absorption, the factors associated with iron metabolism. On the other hand, the iron level also affects the abundance, composition, and metabolism of intestinal flora. The crosstalk between these factors is of significant importance in human metabolism and exerts varying degrees of influence on the manifestation and progression of MetS-related comorbidities. The findings derived from these studies can enhance our comprehension of the interplay between intestinal flora and iron metabolism, and open up novel potential therapeutic approaches toward MetS-related comorbidities.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Hipertensão , Síndrome Metabólica , Feminino , Humanos , Síndrome Metabólica/complicações , Síndrome Metabólica/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Obesidade/complicações , Obesidade/metabolismo , Ferro/metabolismo , Hipertensão/complicações
18.
Adv Mater ; 36(26): e2313327, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38402420

RESUMO

Choreographing the adaptive shapes of patterned surfaces to exhibit designable mechanical interactions with their environment remains an intricate challenge. Here, a novel category of strain-engineered dynamic-shape materials, empowering diverse multi-dimensional shape modulations that are combined to form fine-grained adaptive microarchitectures is introduced. Using micro-origami tessellation technology, heterogeneous materials are provided with strategic creases featuring stimuli-responsive micro-hinges that morph precisely upon chemical and electrical cues. Freestanding multifaceted foldable packages, auxetic mesosurfaces, and morphable cages are three of the forms demonstrated herein of these complex 4-dimensional (4D) metamaterials. These systems are integrated in dual proof-of-concept bioelectronic demonstrations: a soft foldable supercapacitor enhancing its power density (≈108 mW cm-2), and a bio-adaptive device with a dynamic shape that may enable novel smart-implant technologies. This work demonstrates that intelligent material systems are now ready to support ultra-flexible 4D microelectronics, which can impart autonomy to devices culminating in the tangible realization of microelectronic morphogenesis.

19.
Clin Infect Dis ; 56(10): 1373-81, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23378282

RESUMO

BACKGROUND: Enterohemorrhagic Escherichia coli (EHEC) O26 causes diarrhea and hemolytic uremic syndrome (HUS). Strains harboring the stx1a gene prevail, but strains with stx2a as the sole Shiga toxin-encoding gene are now emerging. The traits and virulence of the latter set of strains are unknown. We correlated stx genotypes of 272 EHEC O26 strains isolated in 7 European countries between 1996 and 2012 with disease phenotypes. We determined phylogeny, clonal structure, and plasmid gene profiles of the isolates and portray geographic and temporal distribution of the different subgroups. METHODS: The stx genotypes and plasmid genes were identified using polymerase chain reaction, phylogeny was assigned using multilocus sequence typing, and clonal relatedness was established using pulsed-field gel electrophoresis. RESULTS: Of the 272 EHEC O26 isolates, 107 (39.3%), 139 (51.1%), and 26 (9.6%) possessed stx1a, stx2a, or both genes, respectively. Strains harboring stx2a only were significantly associated with HUS (odds ratio, 14.2; 95% confidence interval, 7.9-25.6; P < .001) compared to other stx genotypes. The stx2a-harboring strains consist of 2 phylogenetically distinct groups defined by sequence type (ST) 21 and ST29. The ST29 strains are highly conserved and correspond by plasmid genes to the new virulent clone of EHEC O26 that emerged in Germany in the 1990s. This new clone occurred in 6 of the 7 countries and represented approximately 50% of all stx2a-harboring EHEC O26 strains isolated between 1996 and 2012. CONCLUSIONS: A new highly virulent clone of EHEC O26 has emerged in Europe. Its reservoirs and sources warrant identification.


Assuntos
Escherichia coli Êntero-Hemorrágica/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Adolescente , Adulto , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , DNA Bacteriano/genética , Eletroforese em Gel de Campo Pulsado , Escherichia coli Êntero-Hemorrágica/genética , Escherichia coli Êntero-Hemorrágica/patogenicidade , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/epidemiologia , Europa (Continente)/epidemiologia , Feminino , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Fenótipo , Filogenia , Plasmídeos/genética , Reação em Cadeia da Polimerase , Resultado do Tratamento , Adulto Jovem
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