Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Genes (Basel) ; 13(11)2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36421823

RESUMO

Mercury (Hg) pollution poses human health and environmental risks worldwide, as it can have toxic effects and causes selective pressure that facilitates the spread of antibiotic resistant genes (ARGs) among microbes. More and more studies have revealed that numerous Hg-related genes (HRGs) can help to resist and transform Hg. In the present study, we systematically analyzed the HRG distribution, abundance, organization, and their co-distribution with ARGs, using 18,731 publicly available plasmid genomes isolated from a Gammaproteobacteria host. Our results revealed that there were many Hg-resistant (mer) operon genes but they were not extensively distributed across plasmids, with only 9.20% of plasmids harboring HRGs. Additionally, no hgcAB genes (which methylate Hg to create methylmercury) were identified in any of the analyzed plasmids. The host source significantly influenced the number of HRGs harbored by plasmids; plasmids isolated from humans and animals harbored a significantly smaller number of HRGs than plasmids isolated from the wastewater and sludge. HRG clusters displayed an extremely high organizational diversity (88 HRG cluster types), though incidences of more than half of the HRG cluster types was <5. This indicates the frequent rearrangement among HRGs in plasmids. The 1368 plasmids harboring both HRGs and ARGs, were dominated by Klebsiella, followed by Escherichia, Salmonella, and Enterobacter. The tightness of the HRG and ARG co-distribution in plasmids was affected by the host sources but not by pathogenicity. HRGs were more likely to co-occur with specific ARG classes (sulfonamide, macrolide-lincosamide-streptogramin, and aminoglycoside resistance genes). Collectively, our results reveal the distribution characteristics of HRGs in plasmids, and they have important implications for further understanding the environmental risks caused by the spread of ARGs through the plasmid-mediated co-transfer of ARGs and HRGs.


Assuntos
Gammaproteobacteria , Mercúrio , Animais , Humanos , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Gammaproteobacteria/genética , Mercúrio/toxicidade , Plasmídeos/genética
2.
Artigo em Inglês | MEDLINE | ID: mdl-28825613

RESUMO

Performance analysis is an important way for hospitals to achieve higher efficiency and effectiveness in providing services to their customers. The performance of the healthcare system can be measured by many indicators, but it is difficult to improve them simultaneously due to the limited resources. A feasible way is to identify the central and influential indicators to improve healthcare performance in a stepwise manner. In this paper, we propose a hybrid multiple criteria decision making (MCDM) approach to identify key performance indicators (KPIs) for holistic hospital management. First, through integrating evidential reasoning approach and interval 2-tuple linguistic variables, various assessments of performance indicators provided by healthcare experts are modeled. Then, the decision making trial and evaluation laboratory (DEMATEL) technique is adopted to build an interactive network and visualize the causal relationships between the performance indicators. Finally, an empirical case study is provided to demonstrate the proposed approach for improving the efficiency of healthcare management. The results show that "accidents/adverse events", "nosocomial infection", ''incidents/errors", "number of operations/procedures" are significant influential indicators. Also, the indicators of "length of stay", "bed occupancy" and "financial measures" play important roles in performance evaluation of the healthcare organization. The proposed decision making approach could be considered as a reference for healthcare administrators to enhance the performance of their healthcare institutions.


Assuntos
Tomada de Decisões , Técnicas de Apoio para a Decisão , Administração Hospitalar/métodos
3.
Bioresour Technol ; 183: 248-54, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25746301

RESUMO

In this study, one- and two-step pretreatments with alkali and acid were performed in the three Miscanthus species that exhibit distinct hemicelluloses levels. As a result, one-step with 4% NaOH or two-step with 2% NaOH and 1% H2SO4 was examined to be optimal for high biomass saccharification, indicating that alkali was the main effecter of pretreatments. Notably, both one- and two-step pretreatments largely enhanced biomass digestibility distinctive in hemicelluloses-rich samples by effectively co-extracting hemicelluloses and lignin. However, correlation analysis further indicated that the effective lignin extraction, other than the hemicelluloses removals, predominately determined biomass saccharification under various alkali and acid pretreatments, leading to a significant alteration of cellulose crystallinity. Hence, this study has suggested the potential approaches in bioenergy crop breeding and biomass process technology.


Assuntos
Biomassa , Biotecnologia/métodos , Metabolismo dos Carboidratos/efeitos dos fármacos , Lignina/isolamento & purificação , Poaceae/metabolismo , Polissacarídeos/metabolismo , Hidróxido de Sódio/farmacologia , Ácidos Sulfúricos/farmacologia , Parede Celular/química , Parede Celular/efeitos dos fármacos , Celulose/análise , Hexoses/análise , Poaceae/efeitos dos fármacos
4.
Bioresour Technol ; 169: 447-454, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25079210

RESUMO

In this study, various alkali-pretreated lignocellulose enzymatic hydrolyses were evaluated by using three standard pairs of Miscanthus accessions that showed three distinct monolignol (G, S, H) compositions. Mfl26 samples with elevated G-levels exhibited significantly increased hexose yields of up to 1.61-fold compared to paired samples derived from enzymatic hydrolysis, whereas Msa29 samples with high H-levels displayed increased hexose yields of only up to 1.32-fold. In contrast, Mfl30 samples with elevated S-levels showed reduced hexose yields compared to the paired sample of 0.89-0.98 folds at p<0.01. Notably, only the G-rich biomass samples exhibited complete enzymatic hydrolysis under 4% NaOH pretreatment. Furthermore, the G-rich samples showed more effective extraction of lignin-hemicellulose complexes than the S- and H-rich samples upon NaOH pretreatment, resulting in large removal of lignin inhibitors to yeast fermentation. Therefore, this study proposes an optimal approach for minor genetic lignin modification towards cost-effective biomass process in Miscanthus.


Assuntos
Biotecnologia/métodos , Fermentação/efeitos dos fármacos , Guaiaco/isolamento & purificação , Lignina/isolamento & purificação , Poaceae/metabolismo , Saccharomyces cerevisiae/fisiologia , Hidróxido de Sódio/farmacologia , Biomassa , Biotecnologia/economia , Análise Custo-Benefício , Etanol/metabolismo , Poaceae/efeitos dos fármacos , Polissacarídeos/isolamento & purificação , Saccharomyces cerevisiae/efeitos dos fármacos , Fatores de Tempo
5.
PLoS One ; 9(8): e105115, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25133694

RESUMO

Plant lignin is one of the major wall components that greatly contribute to biomass recalcitrance for biofuel production. In this study, total 79 representative Miscanthus germplasms were determined with wide biomass digestibility and diverse monolignol composition. Integrative analyses indicated that three major monolignols (S, G, H) and S/G ratio could account for lignin negative influence on biomass digestibility upon NaOH and H2SO4 pretreatments. Notably, the biomass enzymatic digestions were predominately affected by the non-KOH-extractable lignin and interlinked-phenolics, other than the KOH-extractable ones that cover 80% of total lignin. Furthermore, a positive correlation was found between the monolignols and phenolics at p<0.05 level in the non-KOH-extractable only, suggesting their tight association to form the minor wall-networks against cellulases accessibility. The results indicated that the non-KOH-extractable lignin-complex should be the target either for cost-effective biomass pretreatments or for relatively simply genetic modification of plant cell walls in Miscanthus.


Assuntos
Lignina/metabolismo , Fenóis/metabolismo , Poaceae/metabolismo , Biomassa , Celulases/metabolismo , Poaceae/genética
6.
Biochem Biophys Res Commun ; 430(3): 1151-6, 2013 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-23246835

RESUMO

4-Coumarate:coenzyme A ligase (4CL) catalyzes the conversion of hydroxycinnamates into corresponding CoA esters for biosynthesis of flavonoids and lignin. In this study, five members of the 4CL gene family from rice were cloned and analyzed. Recombinant 4CL data revealed that 4-coumaric acid and ferulic acid were the two main substrates of 4CL (Os4CL1/3/4/5) for monolignol biosynthesis in rice. Os4CL2 was specifically expressed in the anther and was strongly activated by UV irradiation, suggesting its potential involvement in flavonoid formation. Moreover, bioinformatics analysis showed that the existence of valine residue at the substrate-binding pocket may mainly affect rice 4CL activities toward sinapic acid.


Assuntos
Coenzima A Ligases/metabolismo , Flavonoides/biossíntese , Lignina/biossíntese , Oryza/enzimologia , Estresse Fisiológico/genética , Sequência de Aminoácidos , Sítios de Ligação , Clonagem Molecular , Coenzima A Ligases/química , Coenzima A Ligases/genética , Regulação da Expressão Gênica de Plantas , Cinética , Dados de Sequência Molecular , Oryza/genética
7.
Ying Yong Sheng Tai Xue Bao ; 16(3): 505-8, 2005 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-15943366

RESUMO

A comparative study on the field attraction effects of different attractant, trap, lure and controlled-releasing amount on Monochamus alternatus showed that four test attractants had a certain trapping ability to Monochamus alternatus, among which, MA2K05 was the strongest, with a mean capture efficiency of 26.3 individuals each trap and being attractive to other species of Loleoptera and Hemiptera; MA2K13 took the second place, with 21.3 individuals each trap; while MA2K11 was the weakest, with 13.8 individuals each trap. Among the three lures tested, lures C (60 ml plastic cup with 2 of 5 cm round holes on the cover) and B (20 ml specified controlled-releasing plastic bottle) had a comparatively stronger effect, with a capture efficiency of 34.25 and 20.3 individuals each trap, respectively; while lure A (20 ml specified controlled-releasing plastic bottle, the releasing amount being smaller than that of lure B) was the weakest, with 14.7 individuals each trap. Because the attractant volume of lure C was 1.5 times larger than that of lures B and A, and the attractant for lure C was appended every 3-5 d, while that for lures B and A could be used for more than a month with once appended, lure B was the best on the whole. As for the test traps, Xuanzhou trap was superior to imitated Japanese trap, with a trapping efficiency of 36.4 and 9.7 individuals each trap, respectively. The attractiveness of attractants was not significantly enhanced when the dosage was increased from 20 ml to 80 ml, but significantly improved when it was up to 120 ml.


Assuntos
Dípteros , Controle de Insetos/métodos , Feromônios , Animais , Controle Biológico de Vetores
8.
Ying Yong Sheng Tai Xue Bao ; 16(2): 317-22, 2005 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15852930

RESUMO

With scanning electron microscope (SEM), this paper observed the shape, category, amount and distribution of the main antenna sensilla of adult Monochamus alternatus, and tested their electroantennographic (EAG) responses to the main volatiles of Pinus spp.. There were seven types of antennal sensilla, i. e., sensilla trichoid, sensilla basiconica, sensilla digit-like, sensilla rod-like, sensilla bottle-like, sensilla bud-like and sensilla chaetica, among which, sensilla trichoid and sensilla basiconica were the most abundant on the antenna surface, and each of them could be divided into three subtypes. Two subtypes of sensilla digit-like could also be observed. The II and III subtypes of sensilla trichoid and I and II subtypes of sensilla basiconica had deep longitudinal grooves on their surface, the typical characteristics of olfactory receptor. The comparison of the EAG response of different parts of Monochamus alternatus antennae to alpha-Pinene showed that each volatile and their compounds could provoke significant EAG responses of both females and males. The dose-response test showed that there was a certain rule in the EAG responses of M. alternatus.


Assuntos
Besouros/ultraestrutura , Pinus/parasitologia , Doenças das Plantas/parasitologia , Células Receptoras Sensoriais/ultraestrutura , Animais , Besouros/fisiologia , Pinus/crescimento & desenvolvimento , Células Receptoras Sensoriais/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...