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2.
Environ Sci Pollut Res Int ; 30(19): 55092-55111, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36884176

RESUMO

The spatiotemporal characteristics, relationship with meteorological factors, and source distribution of air pollutants (January 2017-December 2021) were analyzed to better understand the air pollutants on the northern slope of the Tianshan Mountains (NSTM) in Xinjiang, a heavily polluted urban agglomeration of heavy industries. The results showed that the annual mean concentrations of SO2, NO2, CO, O3, PM2.5, and PM10 were 8.61-13.76 µg m-3, 26.53-36.06 µg m-3, 0.79-1.31 mg m-3, 82.24-87.62 µg m-3, 37.98-51.10 µg m-3, and 84.15-97.47 µg m-3. The concentrations of air pollutants (except O3) showed a decreasing trend. The highest concentrations were in winter, and in Wujiaqu, Shihezi, Changji, Urumqi, and Turpan, the concentrations of particulate matter exceeded the NAAQS Grade II during winter. The west wind and the spread of local pollutants both substantially impacted the high concentrations. According to the analysis of the backward trajectory in winter, the air masses were mainly from eastern Kazakhstan and local emission sources, and PM10 in the airflow had a more significant impact on Turpan; the rest of the cities were more affected by PM2.5. Potential sources included Urumqi-Changj-Shihezi, Turpan, the northern Bayingol Mongolian Autonomous Prefecture, and eastern Kazakhstan. Consequently, the emphasis on improving air quality should be on reducing local emissions, strengthening regional cooperation, and researching transboundary transport of air pollutants.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Cidades , Monitoramento Ambiental/métodos , Poluição do Ar/análise , Poluentes Atmosféricos/análise , Material Particulado/análise , Estações do Ano , China
3.
MedComm (2020) ; 2(1): 91-100, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34766137

RESUMO

Increasing evidence has accrued indicating that autophagy is associated with hepatic ischemia-reperfusion injury (IRI). This report demonstrates that interferon regulatory factor-1 (IRF-1) was upregulated in response to hepatic IRI and was associated with autophagic activation. As a result of these processes, there is an aggravation of liver damage, effects that can be offset by IRF-1 depletion. In addition, these effects of IRF-1 are associated with JNK pathway activation followed by increases in Beclin1 protein levels. This JNK-induced autophagic cell death then leads to cell failure, and plays an important role in liver function damage. We conclude that IRF-1 activates autophagy through JNK-mediated autophagy. Accordingly, these findings indicating that the IRF-1/JNK pathway activates autophagy to exacerbate liver IRI in this mouse model may provide new insights into novel protective therapies for hepatic IRI.

4.
ACS Omega ; 6(38): 24672-24682, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34604649

RESUMO

The key to the efficient development of a tight reservoir is its accurate evaluation. In this study, the pore throat structure characteristics of sandstone samples in the study block were analyzed by high-pressure mercury injection technology. According to the characteristics of the capillary pressure curve, the sandstone samples in the study block were divided into three types: the first type has a reservoir permeability greater than 0.7 mD and a core mercury injection saturation of 96% with a good reservoir quality; the second type has a reservoir permeability ranging from 0.4 to 0.7 mD and a core mercury injection saturation of 80% with a moderate reservoir quality; and the third type has a reservoir permeability between 0.1 and 0.4 mD and a core mercury injection saturation of 50% with a poor reservoir quality. Also, high-resolution synchrotron radiation imaging and scanning electron microscopy were used to observe the pore throat structure, connectivity, and microscopic heterogeneity of sandstone samples, showing an increasing level of pore disconnection, serious microscopic heterogeneity, and poor reservoir performance as reservoir permeability declines. As mineral composition tests show, the lithology of the tight sandstone in the target block is mainly medium-grained and fine-grained feldspar lithic sandstone and the longitudinal heterogeneity of lithology and mineral components of tight sandstone is relatively weak at above the centimeter level. Besides, based on the high-pressure mercury injection test data, fractal theory is applied to calculate the fractal dimensions of the three types of reservoirs. The result shows a gradual increase in fractal dimensions with the decrease of reservoir quality, in which the closer the fractal dimension is to 3, the more serious the microscopic heterogeneity is, and the stronger the roughness of the pore surface is. As a result, the more heterogeneous the tight reservoir gets, the more likely the injected fluid is to flow along the developed and connected pore regions.

5.
Infect Drug Resist ; 14: 1415-1422, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33880046

RESUMO

BACKGROUND: ST11 is the most prevalent sequence type of clinical Klebsiella pneumoniae in China. METHODS: We investigated the characteristics of the ST11 subclones using core genome multi-locus sequence typing (cgMLST). Ninety-three carbapenemase-producing K. pneumoniae isolates were collected at Shenzhen People's Hospital. Then, whole-genome sequencing and cgMLST were used to discriminate apparent subclones within the ST11 group. RESULTS: We analyzed the prevalence and genetic relationships of these subclones. ST11 and K. pneumoniae carbapenemase (KPC-2) were the predominant genotype and carbapenemase, respectively, in the clinical carbapenemase-producing K. pneumoniae strains. cgMLST scheme genotyping divided the ST11 group into two clades across seven complex types (CTs). CT1313 was the most prevalent subclone. The deletion of galF and a high frequency of SNPs in genes associated with the stress- and SOS-responses were found in CT1291 and CT2405 over time, respectively. CONCLUSION: Our results indicated that the subclones of the ST11 group had different patterns of prevalence. Highly discriminatory genotyping techniques, such as cgMLST scheme, should be used in further molecular epidemiology investigations.

6.
J Antibiot (Tokyo) ; 74(5): 324-329, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33456052

RESUMO

The threat of antimicrobial resistance calls for more efforts in basic science, drug discovery, and clinical development, particularly gram-negative carbapenem-resistant pathogens. We sought to identify novel antibacterial agents against Acinetobacter baumannii ATCC19606 using whole cell-based screening. A small molecule named 6D1 with the chemical structure of 6-fluorobenzo[d]isothiazol-3(2H)-one was identified and exhibited activity against A. baumannii ATCC19606 strain (minimal inhibitory concentration, MIC = 1 mg l-1). The mutation in the plasmid-derived ohrB gene that encodes a peroxidase was identified in spontaneously resistant mutants. Treatment of the bacteria with 6D1 resulted in increased sensitivity to peroxide, such as tert-butyl hydroperoxide. The binding of 6D1 and OhrB was confirmed by surface plasmon resonance. Interestingly, the MIC of kanamycin and gentamicin against spontaneously resistant mutants decreased. Finally, we identified the effect of 6D1 on enhancing the antibacterial activity of kanamycin and gentamicin, including against New Delhi metallo-ß-lactamase (NDM-1)-producing carbapenem-resistant Klebsiella pneumoniae, but not in strains carrying aminoglycosides resistance genes. In this study, we identified a small molecule that suppresses the growth of A. baumannii, interacts with hydroperoxide reductase from A. baumannii ATCC19606 plasmid pMAC, and enhances the antibacterial activity of kanamycin and gentamicin. We propose that peroxidase may be potentially used as a target for aminoglycosides adjuvant development.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Klebsiella pneumoniae/efeitos dos fármacos , Peroxirredoxinas/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Aminoglicosídeos/administração & dosagem , Farmacorresistência Bacteriana Múltipla , Sinergismo Farmacológico , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Testes de Sensibilidade Microbiana , Sequenciamento Completo do Genoma
7.
Infect Drug Resist ; 13: 4125-4132, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33209042

RESUMO

OBJECTIVE: We aimed to establish a tool for rapid identification of KL49 Acinetobacter baumannii. METHODS: Based on the capsular polysaccharide (CPS) synthesis genes database, we investigated the distribution of K locus type 49 (KL49) genes in other KL types and established a rapid identification method for KL49. We collected 61 clinical carbapenem-resistant A. baumannii (CRAB) strains, identified KL49 by gtr100 detection, and used whole genome sequencing (WGS) for verification. A mouse pneumonia model was used to confirm the hypervirulence phenotype. We tested the presence of gtr100 gene in 165 CRAB strains from three provinces in China and evaluated the correlation of gtr100 carrying CRAB infection with mortality. RESULTS: The gtr100 gene is the CPS synthesis gene found only in KL49. We screened out nine WGS-validated KL49 strains from 61 CRAB clinical strains using polymerase chain reaction (PCR) to detect the gtr100 gene. The survival rates of KL49 strains were significantly lower than nonKL49 strains in a mouse pneumonia model. The survival rates of LAC-4 gtr100 knockout strain decreased significantly. Analysis of phylogenetics showed the worldwide spread of KL49 A. baumannii. Infection of gtr100 carrying CRAB is an independent risk for mortality (OR, 10.76; 95%CI: 3.08-37.55; p<0.001). CONCLUSION: The hypervirulence phenotype of KL49 CRAB and the association with mortality highlight the urgent need for implementing control measures. The rapid identification assay has the potential to facilitate early medical intervention and worldwide surveillance.

8.
Nutr J ; 17(1): 57, 2018 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-29859104

RESUMO

OBJECTIVE: This study aimed to investigate the possible effect of omega-3 fatty acids on reducing the mortality of sepsis and sepsis-induced acute respiratory distress syndrome (ARDS) in adults. METHODS: Medline, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI) database, WangFang database, and Chinese BioMedical Literature Database from their inception to March 6, 2017, were searched using systematic review researching methods. Five factors were analyzed to investigate the correlation between omega-3 fatty acids (either parenteral or enteral supplementation) and mortality rate. RESULTS: Forty randomized controlled trials (RCTs) were initially included, but only 25 of them assessed mortality. Of these RCTs, nine used enteral nutrition (EN) and 16 used parenteral nutrition (PN). The total mortality rate in the omega-3 fatty acid group was lower than that in the control group. However, the odds ratio (OR) value was not significantly different in the EN or PN subgroup. Eighteen RCTs including 1790 patients with similar severity of sepsis and ARDS were also analyzed. The OR value was not significantly different in the EN or PN subgroup. Omega-3 fatty acids did not show positive effect on improving mortality of sepsis-induced ARDS (p = 0.39). But in EN subgroup, omega-3 fatty acids treatment seemed to have some benefits in reducing mortality rate (p = 0.04). In the RCTs including similar baseline patients, partial correlation analysis found that the concentration ratio of n-6 to n-3 fatty acids had positive correlation with reduction of mortality (RM) (γ = 0.60, P = 0.02), whereas the total number of each RCT had negative correlation with RM (γ = - 0.54, P = 0.05). CONCLUSIONS: This review found that omega-3 fatty acid supplementation could reduce the mortality rate of sepsis and sepsis-induced ARDS. However, further investigation based on suitable concentrations and indications is needed to support the findings.


Assuntos
Ácidos Graxos Ômega-3/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Síndrome do Desconforto Respiratório/epidemiologia , Síndrome do Desconforto Respiratório/etiologia , Sepse/complicações , Sepse/mortalidade , Adulto , Suplementos Nutricionais , Humanos , MEDLINE , Razão de Chances , Síndrome do Desconforto Respiratório/prevenção & controle , Sepse/prevenção & controle
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