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1.
Diabetes Obes Metab ; 26(7): 2673-2683, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38558498

RESUMO

AIM: To investigate the association between cardiovascular health metrics defined by Life's Essential 8 (LE8) scores and vascular complications among individuals with type 2 diabetes (T2D). MATERIALS AND METHODS: This prospective study included 11 033 participants with T2D, all devoid of macrovascular diseases (including cardiovascular and peripheral artery disease) and microvascular complications (e.g. diabetic retinopathy, neuropathy and nephropathy) at baseline from the UK Biobank. The LE8 score comprised eight metrics: smoking, body mass index, physical activity, non-high-density lipoprotein cholesterol, blood pressure, glycated haemoglobin, diet and sleep duration. Cox proportional hazards models were established to assess the associations of LE8 scores with incident macrovascular and microvascular complications. RESULTS: During a median follow-up of 12.1 years, we identified 1975 cases of incident macrovascular diseases and 1797 cases of incident microvascular complications. After adjusting for potential confounders, each 10-point increase in the LE8 score was associated with an 18% lower risk of macrovascular diseases and a 15% lower risk of microvascular complications. Comparing individuals in the highest and lowest quartiles of LE8 scores revealed hazard ratios of 0.55 (95% confidence interval 0.47-0.62) for incident macrovascular diseases, and 0.61 (95% confidence interval 0.53-0.70) for incident microvascular complications. This association remained robust across a series of sensitivity analyses and nearly all subgroups. CONCLUSION: Higher LE8 scores were associated with a lower risk of incident macrovascular and microvascular complications among individuals with T2D. These findings underscore the significance of adopting fundamental strategies to maintain optimal cardiovascular health and curtail the risk of developing diabetic vascular complications.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Angiopatias Diabéticas , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Masculino , Feminino , Estudos Prospectivos , Pessoa de Meia-Idade , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/etiologia , Reino Unido/epidemiologia , Idoso , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Adulto , Fatores de Risco , Índice de Massa Corporal , Fumar/efeitos adversos , Fumar/epidemiologia , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/metabolismo , Exercício Físico , Seguimentos , Pressão Sanguínea , Incidência
2.
Arterioscler Thromb Vasc Biol ; 43(9): 1684-1699, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37409531

RESUMO

BACKGROUND: Excess aldosterone is implicated in vascular calcification (VC), but the mechanism by which aldosterone-MR (mineralocorticoid receptor) complex promotes VC is unclear. Emerging evidence indicates that long-noncoding RNA H19 (H19) plays a critical role in VC. We examined whether aldosterone-induced osteogenic differentiation of vascular smooth muscle cells (VSMCs) through H19 epigenetic modification of Runx2 (runt-related transcription factor-2) in a MR-dependent manner. METHODS: We induced in vivo rat model of chronic kidney disease using a high adenine and phosphate diet to explore the relationship among aldosterone, MR, H19, and VC. We also cultured human aortic VSMCs to explore the roles of H19 in aldosterone-MR complex-induced osteogenic differentiation and calcification of VSMCs. RESULTS: H19 and Runx2 were significantly increased in aldosterone-induced VSMC osteogenic differentiation and VC, both in vitro and in vivo, which were significantly blocked by the MR antagonist spironolactone. Mechanistically, our findings reveal that the aldosterone-activated MR bound to H19 promoter and increased its transcriptional activity, as determined by chromatin immunoprecipitation, electrophoretic mobility shift assay, and luciferase reporter assay. Silencing H19 increased microRNA-106a-5p (miR-106a-5p) expression, which subsequently inhibited aldosterone-induced Runx2 expression at the posttranscriptional level. Importantly, we observed a direct interaction between H19 and miR-106a-5p, and downregulation of miR-106a-5p efficiently reversed the suppression of Runx2 induced by H19 silencing. CONCLUSIONS: Our study clarifies a novel mechanism by which upregulation of H19 contributes to aldosterone-MR complex-promoted Runx2-dependent VSMC osteogenic differentiation and VC through sponging miR-106a-5p. These findings highlight a potential therapeutic target for aldosterone-induced VC.


Assuntos
MicroRNAs , RNA Longo não Codificante , Calcificação Vascular , Humanos , Ratos , Animais , MicroRNAs/metabolismo , Aldosterona/toxicidade , RNA Longo não Codificante/metabolismo , Osteogênese , Calcificação Vascular/induzido quimicamente , Calcificação Vascular/genética , Calcificação Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo
3.
Environ Res ; 252(Pt 1): 118881, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38582430

RESUMO

Nitrate reduction in bio-electrochemical systems (BESs) has attracted wide attention due to its low sludge yields and cost-efficiency advantages. However, the high resistance of traditional electrodes is considered to limit the denitrification performance of BESs. Herein, a new graphene/polypyrrole (rGO/PPy) modified electrode is fabricated via one-step electrodeposition and used as cathode in BES for improving nitrate removal from wastewater. The formation and morphological results support the successful formation of rGO/PPy nanohybrids and confirm the part covalent bonding of Py into GO honeycomb lattices to form a three-dimensional cross-linked spatial structure. The electrochemical tests indicate that the rGO/PPy electrode outperforms the unmodified electrode due to the 3.9-fold increase in electrochemical active surface area and 6.9-fold decrease in the charge transfer resistance (Rct). Batch denitrification activity tests demonstrate that the BES equipped with modified rGO/PPy biocathode could not only achieve the full denitrification efficiency of 100% with energy recovery (15.9 × 10-2 ± 0.14 A/m2), but also favor microbial attach and growth with improved biocompatible surface. This work provides a feasible electrochemical route to fabricate and design a high-performance bioelectrode to enhance denitrification in BESs.


Assuntos
Desnitrificação , Eletrodos , Grafite , Polímeros , Pirróis , Grafite/química , Polímeros/química , Pirróis/química , Técnicas Eletroquímicas/métodos , Fontes de Energia Bioelétrica , Nitratos/química , Carbono/química , Fibra de Carbono/química
4.
J Autoimmun ; 116: 102562, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33168359

RESUMO

Adult-onset Still's disease (AOSD) is a rare autoinflammatory disease with systemic involvement, and its pathophysiology remains unclear. Genome-wide association studies (GWAS) in the Chinese population have revealed an association between AOSD and the major histocompatibility complex (MHC) locus; however, causal variants in the MHC remain undetermined. In the present study, we identified independent amino-acid polymorphisms in human leukocyte antigen (HLA) molecules that are associated with Han Chinese patients with AOSD by fine-mapping the MHC locus. Through conditional analyses, we identified position 34 in HLA-DQα1 (p = 1.44 × 10-14) and Asn in HLA-DRß1 position 37 (p = 5.12 × 10-11) as the major determinants for AOSD. Moreover, we identified the associations for three main HLA class II alleles: HLA-DQB1*06:02 (OR = 2.70, p = 3.02 × 10-14), HLA-DRB1*15:01 (OR = 2.44, p = 3.66 × 10-13), and HLA-DQA1*01:02 (OR = 1.97, p = 1.09 × 10-9). This study reveals the relationship between functional variations in the class II HLA region and AOSD, implicating the MHC locus in the pathogenesis of AOSD.


Assuntos
Aminoácidos/genética , Predisposição Genética para Doença/genética , Cadeias alfa de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Polimorfismo de Nucleotídeo Único , Doença de Still de Início Tardio/genética , Adulto , Alelos , Povo Asiático/genética , China , Frequência do Gene , Predisposição Genética para Doença/etnologia , Estudo de Associação Genômica Ampla/métodos , Genótipo , Cadeias alfa de HLA-DQ/química , Cadeias HLA-DRB1/química , Haplótipos , Humanos , Desequilíbrio de Ligação , Modelos Moleculares , Conformação Proteica , Doença de Still de Início Tardio/etnologia
5.
Sensors (Basel) ; 21(6)2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33809307

RESUMO

Recent years have seen the wide application of Location-Based Services (LBSs) in our daily life. Although users can enjoy many conveniences from the LBSs, they may lose their trajectory privacy when their location data are collected. Therefore, it is urgent to protect the user's trajectory privacy while providing high quality services. Trajectory k-anonymity is one of the most important technologies to protect the user's trajectory privacy. However, the user's attributes are rarely considered when constructing the k-anonymity set. It results in that the user's trajectories are especially vulnerable. To solve the problem, in this paper, a Spatiotemporal Mobility (SM) measurement is defined for calculating the relationship between the user's attributes and the anonymity set. Furthermore, a trajectory graph is designed to model the relationship between trajectories. Based on the user's attributes and the trajectory graph, the SM based trajectory privacy-preserving algorithm (MTPPA) is proposed. The optimal k-anonymity set is obtained by the simulated annealing algorithm. The experimental results show that the privacy disclosure probability of the anonymity set obtained by MTPPA is about 40% lower than those obtained by the existing algorithms while the same quality of services can be provided.

6.
J Infect Dis ; 221(Suppl 2): S229-S236, 2020 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-32176784

RESUMO

BACKGROUND: This study was performed to assess the role of the histone-like nucleoid-structuring (H-NS)-like protein, carried by blaNDM-1-encoding IncX3-type plasmids, in the dissemination of IncX3 plasmids. METHODS: The blaNDM-1-encoding IncX3 plasmids were analyzed using southern blot, conjugation, and competition assays. Virulence was evaluated with a Galleria mellonella infection model. An hns-knockout IncX3 plasmid was also constructed to identify the functions of plasmid-borne H-NS-like protein in Escherichia coli. RESULTS: The assasys detected blaNDM-1-encoding IncX3-type plasmids with similar fingerprint patterns in all New Delhi metallo-ß-lactamase (NDM) 1-producing carbapenem-resistant Enterobacteriaceae. The IncX3 plasmid conferred a fitness advantage to E. coli J53 but had no effect on host virulence. Moreover, the transconjugation frequency of the hns-null IncX3 plasmid pHN330-△hns was increased by 2.5-fold compared with the wild type. This was caused by up-regulation of conjugation-related plasmid-borne genes and the partition-related gene, in the J330-pHN330-△hns strain. In addition, decreased virulence was detected with this variant. CONCLUSIONS: Our results highlight the important role of IncX3 plasmids in the dissemination of blaNDM-1 in south China. Plasmid-encoded H-NS-like protein can inhibit plasmid conjugation, partition, and the expression of related genes, in addition to promoting virulence in the host.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli/genética , Transferência Genética Horizontal/genética , Plasmídeos/genética , beta-Lactamases/genética , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , China , Infecções por Enterobacteriaceae/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Virulência/genética
7.
Artigo em Inglês | MEDLINE | ID: mdl-31182541

RESUMO

The presence and molecular characteristics of carbapenemase-producing Enterobacteriaceae (CPE) among meat products in China were investigated. A total of 110 carbapenem-resistant Enterobacteriaceae (CRE) isolates, including 94 Escherichia coli and 10 Klebsiella pneumoniae isolates, were identified from 105 of 794 (13.2%) samples. The positive rates markedly increased from 2016 (9.4%) to 2018 (22.2%). Only blaNDM genes were detected; 79.1% of blaNDM genes were carried by IncX3 plasmids. Routine monitoring of carbapenemase-producing Enterobacteriaceae in the animal food supply is highly recommended.


Assuntos
Carbapenêmicos/uso terapêutico , Escherichia coli/genética , Klebsiella pneumoniae/genética , Carne/microbiologia , Plasmídeos/genética , beta-Lactamases/genética , Animais , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , China , Escherichia coli/efeitos dos fármacos , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Humanos , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/metabolismo , Klebsiella pneumoniae/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos
8.
Clin Exp Rheumatol ; 37 Suppl 121(6): 52-57, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31573475

RESUMO

OBJECTIVES: As a rare systemic autoinflammatory disease, adult-onset Still's disease (AOSD) has heterogeneous clinical manifestations, response to treatment and outcome. This study tried to assess the clinical characteristics, laboratory tests, and treatments of Chinese AOSD patients, and make a retrospective analysis. METHODS: We collected from 7 hospitals in China a total of 517 Chinese patients with AOSD who satisfied the Yamaguchi criteria. We retrospectively evaluated their clinical features, laboratory tests, treatments and compared them with published data from different studies. All the data in this study were from medical records and further statistic analyses. RESULTS: We evaluated a total of 517 AOSD patients, 72% female, average age of onset was 37.7; spiking fever, rash and arthralgia occurred in 472 (91.3%), 413 (79.9%), 378 (73.1%) cases, respectively. There were 439/513 (85.6%) cases with leukocytosis and 456/476 (95.8%) cases with raised serum ferritin. The highest frequently used medications and regimens for remission were glucocorticoids (498/517, 96.3%), methotrexate (273/517, 52.8%) and hydroxychloroquine (174/517, 33.7%). 84.4%. 357/423 of AOSD cases were able to achieve initial remission with different regimens, mostly including glucocorticoids, methotrexate or hydroxychloroquine. 47.2% of them (244/517) received 30

Assuntos
Glucocorticoides/uso terapêutico , Prednisona/uso terapêutico , Doença de Still de Início Tardio , Adulto , China , Feminino , Humanos , Masculino , Indução de Remissão , Estudos Retrospectivos , Doença de Still de Início Tardio/diagnóstico , Doença de Still de Início Tardio/tratamento farmacológico , Doença de Still de Início Tardio/patologia , Inquéritos e Questionários
9.
Angew Chem Int Ed Engl ; 58(12): 3824-3828, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30663839

RESUMO

A novel niobium oxyiodate sulfate, Nb2 O3 (IO3 )2 (SO4 ), was fabricated by a rational multi-component design under moderate hydrothermal conditions. This multi-component design is inspired by an interesting niobium oxysulfate reaction, which opens a new door for synthetic method to effectively introduce refractory metals such as Nb into crystal structures by hydrothermal synthesis. Nb2 O3 (IO3 )2 (SO4 ) features a cube-like topological structure with a large phase-matching second harmonic generation (SHG) response (6×KDP), a wide transparency window (0.38-8 µm), and a high laser damage threshold (LDT) (20×AgGaS2 ). It has the highest thermostability (stable up to 580 °C under air) among reported non-centrosymmetric (NCS) iodates and sulfates and is stable in water and even concentrated H2 SO4 . Furthermore, Nb2 O3 (IO3 )2 (SO4 ) is a unique nonlinear optical (NLO) material among iodates and sulfates, because its SHG effect is mainly caused by the MO6 units rather than the IO3 or SO4 units, which is demonstrated by density functional theory (DFT) calculations.

10.
Clin Infect Dis ; 67(suppl_2): S179-S188, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30423046

RESUMO

Background: The global dissemination of carbapenem-resistant Acinetobacter baumannii clonal complex (CC) 92 has become an urgent public health concern. Methods: A. baumannii isolates were collected in 5 tertiary hospitals in south China during 2012-2015, and their clinical data were obtained. The clinical characterization was studied by statistical analysis. Whole-genome sequencing and a Galleria mellonella infection model were used to investigate the genetic characterization and pathogenicity of isolates, respectively. Results: Sequence type (ST)457, following ST195, become the second-most prevalent clone in our collection. Patients infected by ST457 had significantly higher 7-day mortality rates (44.4% vs 14.3%; P = .01) and proportions of 7-day deaths (70.6% vs 26.7%; P = .01) than those infected by the other STs of CC92, except for ST195 and ST208. Consistently, the day of death after culture was significantly sooner in patients infected with ST457 than those with the non-ST195/208 members of CC92 (8.71 ± 15.27 vs 25.20 ± 6.51; P = .02). This is accordant with results that ST457 had enhanced virulence with a high mortality rate through use of the G. mellonella larvae infection model. Genomic analysis suggests that ST457 evolved distinctly from the other CC92 members mainly via recombinations. This clone exclusively shared a few virulence factors with the hypervirulence strain LAC-4, including a capsule biosynthesis locus (KL49) that is supposed to be important for the hypervirulence in LAC-4. Conclusions: The rising trends in prevalence and enhanced virulence of ST457 highlight the urgent need for tailored surveillance to control the further dissemination of this clone.


Assuntos
Infecções por Acinetobacter/mortalidade , Acinetobacter baumannii/genética , Acinetobacter baumannii/patogenicidade , Doenças Endêmicas , Fatores de Virulência/genética , Infecções por Acinetobacter/microbiologia , Idoso , Idoso de 80 Anos ou mais , Animais , Técnicas de Tipagem Bacteriana , Carbapenêmicos/farmacologia , China/epidemiologia , Evolução Molecular , Feminino , Genômica , Pneumonia Associada a Assistência à Saúde/epidemiologia , Pneumonia Associada a Assistência à Saúde/microbiologia , Humanos , Larva , Masculino , Pessoa de Meia-Idade , Mariposas , Tipagem de Sequências Multilocus , Prevalência , Virulência , Sequenciamento Completo do Genoma
11.
Inorg Chem ; 56(11): 6275-6280, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28537718

RESUMO

Enantioseparation is an integral process in the pharmaceutical industry, considering the ever-increasing demand for chiral medicine products. As a new material, porous metal-organic frameworks (MOFs) have shown their potential application in this field because their structures are easy to adjust and control. Though chiral recognition between racemic substrates and frameworks has made preliminary progress, discussions of their size-matching effects are rare. Herein with the help of channel-tunable homochiral MOFs (HMOFs), diols of different sizes have been separated in good enantiomeric excess (ee%). In addition, the ee% reaches 67.4% for the first time for diols as large as 1,1,2-triphenyl-1,2-ethanediol, which turns out to be the most effective value so far.


Assuntos
Álcoois/química , Estruturas Metalorgânicas/química , Estrutura Molecular , Tamanho da Partícula , Porosidade , Estereoisomerismo , Propriedades de Superfície
12.
BMC Infect Dis ; 17(1): 804, 2017 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-29284419

RESUMO

BACKGROUND: Streptococcus pneumoniae, the leading pathogen of bacterial infections in infants and the elderly, is responsible for pneumococcal diseases with severe morbidity and mortality. Emergence of drug-resistant strains presented new challenges for treatment and prevention. Vaccination has proven to be an effective means of preventing pneumococcal infection worldwide. Detailed epidemiological information of antibiotic susceptibilities and serotype distribution will be of great help to the management of pneumococcal infections. METHODS: A total of 881 S. pneumoniae isolates were collected from patients at 23 teaching hospitals in 17 different cities from 2011 to 2016. The main specimen types included sputum, blood, broncho-alveolar lavage fluid, pharyngeal swabs, and cerebrospinal fluid. Minimum inhibitory concentrations (MICs) were determined using the agar dilution method. Capsular serotypes were identified using latex agglutination and quellung reaction test. Molecular epidemiology was investigated using multilocus sequence typing. RESULTS: S. pneumoniae isolates were highly resistant to macrolides, tetracycline, and trimethoprim/sulfamethoxazole. The rate of resistance to penicillin was 51.6% (oral breakpoint). However, levofloxacin and moxifloxacin maintained excellent antimicrobial activity and all of the isolated strains were susceptible to vancomycin. Twenty-two serotypes were identified among the 881 isolates. Prevalent serotypes were 19F (25.7%), 19A (14.0%), 15 (6.8%), 6B (3.6%), 6A (3.0%), and 17 (2.8%). The overall vaccine coverage rates for 7- and 13-valent pneumococcal conjugate vaccines were 37.5% and 58.3%, respectively. Vaccine coverage rates in young children and economically underdeveloped regions were higher than those in older adults and developed regions. Vaccine-covered serotypes demonstrated higher resistance compared with uncovered serotypes. Molecular epidemiological typing demonstrated that S. pneumoniae showed significant clonal dissemination and that ST271 (120, 28.3%), ST320 (73, 17.2%) and ST81 (27, 6.6%) were the major STs. CONCLUSIONS: High resistance to clinical routine antibiotics was observed for all 881 S. pneumoniae strains. Drug resistance varied among different serotypes and age groups. Prevalent serotypes among the isolates were 19F, 19A, 15, 6B, 6A, and 17. Community-acquired strains should also be included in future studies to gain a better understanding of the prevalence and resistance of S. pneumoniae in China.


Assuntos
Farmacorresistência Bacteriana/efeitos dos fármacos , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/efeitos dos fármacos , Adolescente , Adulto , Idoso , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , China/epidemiologia , Cidades , Farmacorresistência Bacteriana/fisiologia , Humanos , Lactente , Testes de Fixação do Látex , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Infecções Pneumocócicas/tratamento farmacológico , Vacinas Pneumocócicas/farmacologia , Sorogrupo , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/isolamento & purificação , Vacinas Conjugadas/uso terapêutico , Adulto Jovem
13.
PLoS Pathog ; 10(8): e1004340, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25166864

RESUMO

The rhl quorum-sensing (QS) system plays critical roles in the pathogenesis of P. aeruginosa. However, the regulatory effects that occur directly upstream of the rhl QS system are poorly understood. Here, we show that deletion of gene encoding for the two-component sensor BfmS leads to the activation of its cognate response regulator BfmR, which in turn directly binds to the promoter and decreases the expression of the rhlR gene that encodes the QS regulator RhlR, causing the inhibition of the rhl QS system. In the absence of bfmS, the Acka-Pta pathway can modulate the regulatory activity of BfmR. In addition, BfmS tunes the expression of 202 genes that comprise 3.6% of the P. aeruginosa genome. We further demonstrate that deletion of bfmS causes substantially reduced virulence in lettuce leaf, reduced cytotoxicity, enhanced invasion, and reduced bacterial survival during acute mouse lung infection. Intriguingly, specific missense mutations, which occur naturally in the bfmS gene in P. aeruginosa cystic fibrosis (CF) isolates such as DK2 strains and RP73 strain, can produce BfmS variants (BfmSL181P, BfmSL181P/E376Q, and BfmSR393H) that no longer repress, but instead activate BfmR. As a result, BfmS variants, but not the wild-type BfmS, inhibit the rhl QS system. This study thus uncovers a previously unexplored signal transduction pathway, BfmS/BfmR/RhlR, for the regulation of rhl QS in P. aeruginosa. We propose that BfmRS TCS may have an important role in the regulation and evolution of P. aeruginosa virulence during chronic infection in CF lungs.


Assuntos
Infecções por Pseudomonas/metabolismo , Pseudomonas aeruginosa/patogenicidade , Percepção de Quorum/fisiologia , Transdução de Sinais/fisiologia , Animais , Sequência de Bases , Western Blotting , Ensaio de Desvio de Mobilidade Eletroforética , Feminino , Regulação Bacteriana da Expressão Gênica , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Infecções por Pseudomonas/genética , Pseudomonas aeruginosa/genética , Reação em Cadeia da Polimerase em Tempo Real , Virulência
14.
Chemistry ; 22(15): 5327-34, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-26919304

RESUMO

The pores/channels of porous 3D metal-organic frameworks (MOFs) have been widely applied to incorporate gas, solvent, or organic molecules. On the contrary, the utilization of the interlamellar void of layered metal-organic complexes (MOCs) remains underappreciated, although it is more flexible and available to accommodate molecules with different sizes. In this work, diverse sulfonates have been intercalated purposely into an identical layered MOC, which constructed various novel intercalation compounds possessing fluorescent, white-light emitting, photochromic, homochiral, or nonlinear optical (NLO) properties. With the help of single-crystal X-ray diffraction, their structures and the mutual interactions between the MOC host and the sulfonate guests were characterized. The properties of the guest molecules were tuned and meanwhile some new performances were generated after confining them into the interlayer region. Such a hybrid approach provides an efficient strategy to design and prepare multifunctional materials.

15.
Chemistry ; 22(13): 4460-8, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26864609

RESUMO

A new mixed-ligand metal-organic framework (MOF), ZnATZ-BTB, has been constructed as a luminescent ratiometric thermometer by making use of the intrinsic dual emission at cryogenic temperatures. Its twofold interpenetrated network promotes the Dexter energy transfer (DET) between the mixed organic lumophores. The temperature-dependent luminescent behavior arises from the thermal equilibrium between two separated excited states coupled by DET, which is confirmed by Boltzmann distribution fitting. The small excited-state energy gap allows ZnATZ-BTB to measure and visualize cryogenic temperatures (30-130 K) with significantly high relative sensitivity (up to 5.29% K(-1) at 30 K). Moreover, it is the first example of a ratiometric MOF thermometer the dual emitting sources of which are widely applicable mixed organic ligands, opening up new opportunities for designing such devices.

16.
Inorg Chem ; 55(9): 4199-205, 2016 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-27093469

RESUMO

A mixture of 2D and 1D metal-organic complexes, [ZnL(H2O)2·G1·DEF·2H2O]n (1a: G1 = naphthalene-2,7-disulfonate; DEF = N,N-diethylformamide) and [ZnL(H2O)3·G1·DEF·2H2O]n (2), has been prepared from a hydrogenated Schiff base L and Zn(II) in a DEF-contained solvent system under mild conditions. The yields of 1a and 2 are equivalent; however, they can be tuned by varying the amount of DEF solvent. Increasing the use of DEF tends to form pure 1a, while decreasing it generates 2. Without DEF, another novel 3D four-connected CdSO4 (cds) framework [ZnL(H2O)2·G1·2H2O]n (3) composed of alternated right-handed and left-handed helical chains has been constructed. The amount of DEF solvent has a significant impact on the diverse coordination architectures of 1-3, which is rare in the preparation of metal-organic complexes. The photoluminescence of complexes 1-3 along with naphthalene-2,7-disulfonate has been investigated in the solid state. The luminescent emission of G1 was enhanced greatly after being confined into metal-organic networks. In addition, complexes 1-3 display second-harmonic generation efficiencies, which are approximately 0.58, 0.42, 0.32, and 0.52 times as much as that of potassium dihydrogen phosphate.

17.
Inorg Chem ; 54(8): 3951-7, 2015 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-25853322

RESUMO

Utilizing the mixed-ligand strategy, a novel fourfold-interpenetrated 3D homochiral metal-organic framework (1) with rare pair quadruple-stranded helices was assembled from bpee (1,2-bis(4-pyridyl)ethylene) and NCG (N-carbamyl-l-glutamate). Changing the carbamyl substituent of NCG with benzoyl group (NBzG: N-benzoyl-l-glutamate), a non-interpenetrated 3D homochiral coordination polymer (2) composed of alternate right-handed and left-handed single helix was obtained. When p-tolylsulfonyl substituent was used instead, an interesting homochiral linear structure (3) was formed from mixed-ligand bpee and NTsG (N-p-tolylsulfonyl-l-glutamate), with all individual NTsG being lined up orderly. The steric hindrance of N-substituent of l-glu has a tremendous impact on the construction of these diverse frameworks. Complexes 1-3 display second harmonic generation (SHG) efficiencies, which are approximately 0.32, 0.45, and 0.55 times as much as that of KDP powder.


Assuntos
Complexos de Coordenação/química , Etano/análogos & derivados , Glutamatos/química , Piridinas/química , Zinco/química , Complexos de Coordenação/síntese química , Etano/química , Ligantes , Modelos Moleculares , Estrutura Molecular
18.
Zhonghua Yi Xue Za Zhi ; 95(22): 1739-46, 2015 Jun 09.
Artigo em Zh | MEDLINE | ID: mdl-26704158

RESUMO

OBJECTIVE: To investigate the spectrum and antimicrobial resistance of major pathogensthat causing nosocomial infections in China, 2013. METHODS: Nosocomial cases as well as pathogens causing bloodstream infections (BSI), hospital-acquired pneumonia (HAP) and intra-abdominal infections (IAI) from 13 teaching hospital around China were collected. The minimum inhibitory concentrations (MICs) were determined by the agar dilution method. The CLSI M100-S23 criteria were used for interpretation. RESULTS: Of all cases, 1 022 cases were from BSI, 683 from HAP and 674 from IAI.Escherichia coli and Klebsiella pneumoniae were the most prevalent pathogens causing BSI and IAI while Acinetobacter baumanii (34.6%) and Pseudomonas aeruginosa were dominated in HAP. Tigecycline, imipenem and meropenem exhibited high potency against Enterobacteriaceae and the susceptibilities rates were 95.6%, 94.2%and 95.2% respectively. Enterobacteriaceae demonstrated high resistance against cephalosporins (52.3%) and fluoroquinolones (38.9%) but were susceptible to ß-lactam+inhibitor. Of all the Enterobacteriaceae, 30.5% were ESBLs positive and 4.3% were carbapenem resistant. Acinetobacter baumanii showed low susceptibilities to the microbial agents except for tigecycline (90.5%) and colistin (100%). The rate of carbapenem resistant Acinetobacter baumanii was 76.6%. Amikacin, ciprofloxacin, cefepime and piperacillin/tazobactam showed high antibacterial activity against Pseudomonas aeruginosa with susceptible rate 88.5%, 77.6%, 72.7% and 64.5% respectively. The resistant rate to imipenem and meropenem were 42.1% and 32.2%. All Staphylococcus aureus (166 strains) were susceptible to tigecycline, linezolid, daptomycin and glycopeptides. MRSA accounted for 46.9% of all the Staphylococcus aureus. The prevalence of MRSA in IAI (55.2%) and HAP (54.4%) were higher that that in BSI (35.0%). No Enterococcus strains were found resistant to tigecycline, linezolid and daptomycin. VRE was found in Enterococcus faecium, accounting for 1.9% of all Enterococcus faecium strains. CONCLUSIONS: Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii and Pseudomonas aeruginosa are the most common pathogens causing nosocomial infections. Nosocomial pathogens showed high susceptibilities against tigecycline. For ESBLs-producing Enterobacteriaceae strains, ß-lactam+Inhibitor show high antibacterial activities. Vancomycin, teicoplanin and linezolid exhibit high potency to Staphylococcus aureus and Enterococcus.


Assuntos
Infecção Hospitalar , Infecções Intra-Abdominais , Pneumonia , Antibacterianos , Bacteriemia , Carbapenêmicos , Cefepima , Cefalosporinas , China , Hospitais de Ensino , Humanos , Testes de Sensibilidade Microbiana , Minociclina/análogos & derivados , Tigeciclina , Vancomicina
19.
Zhonghua Jie He He Hu Xi Za Zhi ; 38(1): 18-22, 2015 Jan.
Artigo em Zh | MEDLINE | ID: mdl-25791651

RESUMO

OBJECTIVE: To investigate antimicrobial resistance among pathogens responsible for adult community-acquired respiratory tract infections from 11 hospitals of China. METHODS: From January to December 2012, a total of 599 strains causing adult community-acquired respiratory tract infection were collected from 11 hospitals, including 381 Streptococcus pneumonia, 137 Haemophilus influenza, and 81 Moraxella catarrhalis. The minimal inhibitory concentration (MIC) of antibacterial agents was determined by agar dilution method. RESULTS: Of all the strains, 50% (300/599 strains) were from adults more than 60 years old and only 16.2% (97/599 strains) were from patients aged less than 40 years. According to oral penicillin breakpoints, 56.7% (216/381 strains) of Streptococcus pneumoniae were penicillin non-susceptible strains (PNSSP). More than 90% (345/381 strains) and 39.9% (152/381 strains)-50.7% (193/381 strains) of Streptococcus pneumoniae were resistant to macrolides and oral cephalosporins respectively, but over 97.8% (372/381 strains) and 99% (377/381 strains) were susceptible to levofloxacin and moxifloxacin. PNSSP strains exhibited significant higher resistance to ceftriaxone, amoxicillin/clavulanate, cefaclor and cefuroxime compared with penicillin susceptible Streptococcus pneumoniae (PSSP). The susceptibility rates of Haemophilus influenza to the antimicrobial agents were over 90% except for ampicillin (71.5%, 272/381 strains) and cefaclor (75.2%, 286/381 strains). The prevalence of ß-lactamase positive Haemophilus influenza were 21.9% (30/137 strains), and ß-lactamase positive Haemophilus influenza strains were more resistant to ampicillin, cefaclor, chloramphenicol and tetracycline compared with ß-lactamase-negative strains. Moraxella catarrhalis strains were extremely susceptible to all the antimicrobial agents tested except for clindamycin, azithromycin and clarithromycin. CONCLUSIONS: The activities of macrolides and oral cephalosporins against Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis were limited. Levofloxacin and moxifloxacin exhibited good activities against Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis.


Assuntos
Infecções Comunitárias Adquiridas/etiologia , Farmacorresistência Bacteriana , Infecções Respiratórias/etiologia , Adulto , Antibacterianos , Anti-Infecciosos , Cefalosporinas , China/epidemiologia , Claritromicina , Infecções Comunitárias Adquiridas/epidemiologia , Haemophilus influenzae , Humanos , Levofloxacino , Macrolídeos , Testes de Sensibilidade Microbiana , Moraxella catarrhalis , Penicilinas , Infecções Respiratórias/epidemiologia , Streptococcus pneumoniae , beta-Lactamases
20.
Med Mycol Case Rep ; 44: 100637, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38585188

RESUMO

Central nervous system (CNS) aspergillosis is uncommon in immunocompetent patients. We present a 64-year-old man with chronic otitis media and uncontrolled diabetes. Aspergillus flavus was identified in cerebrospinal fluid via metagenomics next-generation sequencing technology. Initial voriconazole treatment offered limited relief, but personalized dosage adjustments, guided by drug concentration, led to remission. This case underscores the importance of diverse diagnostic approaches and tailored therapy for CNS Aspergillus infections.

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