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1.
Environ Pollut ; 357: 124386, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38897279

RESUMO

Marine sediments serve as crucial reservoirs for polycyclic aromatic hydrocarbons (PAHs), and their PAH signatures offer valuable historical pollution records. This article provides a comprehensive review of the pollution status of 16 priority PAHs in more than 1000 sediments from the East China Sea (ECS). It focuses on the PAH sources, spatiotemporal distributions, driving factors, and ecological risks, with information derived from peer-reviewed papers published between 2003 and 2023. The results revealed that vehicular emissions, mixed combustion sources of coal, biomass, and coke, as well as petrogenic sources, were the primary contributors to PAH pollution in the ECS sediments, accounting for 50%, 34%, and 16%, respectively. Human activities, hydrodynamic mechanisms, and environmental variables such as particle size and organic matter, collectively influenced the distribution of PAHs. Additionally, the population size and economic development played a key role in the temporal distribution of PAHs in the ECS sediments. The ecotoxicity assessment of PAHs in sediments indicated a low risk level. These outcomes are expected to provide environmentalists with detailed and up-to-date insights into sedimentary PAHs in the ECS, helping to develop suitable monitoring plans and strategies for promoting better management of ECS environment.

2.
Artigo em Inglês | MEDLINE | ID: mdl-37874497

RESUMO

Bacterial diarrhea causes serious losses for the sheep industry. Antibiotic resistance acquired by diarrheal bacteria is still a hurdle in the care of animal health. Thus, it is urgent to develop effective alternatives to antibiotics for controlling bacterial diarrhea. We initially isolated Bacillus spp. from Xinjiang fine wool sheep fecal and determined their properties of hemolysis and tolerance to acid and bile salts to identify potential candidates. Subsequently, we studied the position of a candidate in phylogenetic trees by 16S rRNA sequences and its susceptibility to antibiotics, ability to inhibit diarrheal bacteria, and toxicity, as well as its effects on animal health. Fourteen Bacillus spp. strains were isolated from sheep fecal. We identified the non-hemolysis B63 strain, which exhibited a high tolerance to acid and bile salts. Phylogenetic analysis indicated that the B63 strain is a new strain of Bacillus licheniformis. The B. licheniformis B63 strain was prompt to form spores, susceptible to commonly used antibiotics, and able to inhibit diarrhea-associated bacteria, including Escherichia coli, Staphylococcus aureus, and Salmonella typhi. Animal studies determined that B. licheniformis B63 at 4 × 108 CFU/mL was non-toxic to mice and SD rats. Supplement with B. licheniformis B63 promoted the body weight gain of mice, reduced the inflammatory interleukin 6, and increased the jejunum villus height of SD rats. The newly isolated, non-hemolysis, spore-forming B. licheniformis B63 strain should be considered an optimal strain for the development of an effective probiotic supplement to control diarrheal diseases and promote the health of sheep and other animals.

3.
BMJ Open ; 11(11): e053240, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34789496

RESUMO

OBJECTIVES: Carbon monoxide (CO) poisoning is one of the most frequent causes of fatal poisoning worldwide. Few studies have explored the mortality trends of CO poisoning grouped by age and gender, at the regional, national and global levels. We therefore aimed to determine the pattern of CO poisoning mortality, as well as temporal trends at all levels. DESIGN: A cross-sectional survey design was used in this study. SETTING: CO poisoning data collected from the Global Burden of Diseases (GBDs), from 1990 to 2017, was arranged by sex, age, region and country. In addition, we used human development index data at the national level from the World Bank. PARTICIPANTS: We collected over 100 000 information on CO poisoning mortality between 1990 and 2017, derived from the GBD study in 2017. MAIN OUTCOMES AND MEASURES: We have calculated the estimated annual percentage changes in CO poisoning age-standardised mortality rate (ASR), by sex and age at different regions and countries to quantify the temporal trends in CO poisoning ASR. RESULTS: Globally, death cases of CO poisoning decreased 7.2% from 38 210 in 1990 to 35 480 in 2017. The overall ASR decreased by an average of 1.83% (95% CI 2.10% to 1.56%) per year in this period. This decreasing pattern was heterogeneous across ages, regions and countries. The most pronounced decreases were generally observed in countries with a high sociodemographic index, including Estonia, South Korea and Puerto Rico. CONCLUSIONS: Current prevention strategies should be reoriented, and much more targeted and specific strategies should be established in some countries to forestall CO poisoning.


Assuntos
Intoxicação por Monóxido de Carbono , Carga Global da Doença , Intoxicação por Monóxido de Carbono/epidemiologia , Estudos Transversais , Estônia , Saúde Global , Humanos , Mortalidade
4.
PLoS One ; 6(8): e23471, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21858134

RESUMO

Active efflux pump is a primary fluoroquinolone resistant mechanism of clinical isolates of Salmonella enterica serovar Typhimurium. RamA is an essential element in producing multidrug resistant (MDR) S. enterica serovar Typhimurium. The aim of the present study was to elucidate the roles of RamA on the development of ciprofloxacin, the first choice for the treatment of salmonellosis, resistance in S. enterica serovar Typhimurium. Spontaneous mutants were selected via several passages of S. enterica serovar Typhimurium CVCC541 susceptible strain (ST) on M-H agar with increasing concentrations of ciprofloxacin (CIP). Accumulation of ciprofloxacin was tested by the modified fluorometric method. The expression levels of MDR efflux pumps were determined by real time RT-PCR. In ST and its spontaneous mutants, the ramA gene was inactivated by insertion of the kan gene and compensated on a recombinant plasmid pGEXΦ(gst-ramA). The mutant prevention concentration (MPC) and mutant frequencies of ciprofloxacin against ST and a spontaneous mutant in the presence, absence and overexpression of RamA were tested. Four spontaneous mutants (SI1-SI4) were obtained. The SI1 (CIP MICs, 0.1 mg/L) without any target site mutation in its quinolone resistant determining regions (QRDRs) and SI3 (CIP MICs, 16 mg/L) harboring the Ser83→Phe mutation in its QRDR of GyrA strains exhibited reduced susceptibility and resistance to multidrugs, respectively. In SI1, RamA was the main factor that controlled the susceptibility to ciprofloxacin by activating MdtK as well as increasing the expression level of acrAB. In SI3, RamA played predominant role in ciprofloxacin resistance via increasing the expression level of acrAB. Likewise, the deficiency of RamA decreased the MPCs and mutant frequencies of ST and SI2 to ciprofloxacin. In conclusion, the expression of RamA promoted the development of ciprofloxacin resistant mutants of S. enterica serovar Typhimurium. The inhibition of RamA could decrease the appearance of the ciprofloxacin resistant mutants.


Assuntos
Proteínas de Bactérias/fisiologia , Ciprofloxacina/farmacologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/fisiologia , Salmonella typhimurium/efeitos dos fármacos , Transativadores/fisiologia , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Proteínas de Bactérias/genética , Transporte Biológico/efeitos dos fármacos , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Ciprofloxacina/metabolismo , Dipeptídeos/farmacologia , Relação Dose-Resposta a Droga , Farmacorresistência Bacteriana/genética , Farmacorresistência Bacteriana/fisiologia , Farmacorresistência Bacteriana Múltipla/genética , Farmacorresistência Bacteriana Múltipla/fisiologia , Escherichia coli/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Mutação , Ácido Nalidíxico/farmacologia , Regiões Promotoras Genéticas/genética , Ionóforos de Próton/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo , Transativadores/genética
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