RESUMO
Fungal laccase has strong ability in detoxification of many environmental contaminants. A putative laccase gene, LeLac12, from Lentinula edodes was screened by secretome approach. LeLac12 was heterogeneously expressed and purified to characterize its enzymatic properties to evaluate its potential use in bioremediation. This study showed that the extracellular fungal laccase from L. edodes could effectively degrade tetracycline (TET) and the synthetic dye Acid Green 25 (AG). The growth inhibition of Escherichia coli and Bacillus subtilis by TET revealed that the antimicrobial activity was significantly reduced after treatment with the laccase-HBT system. 16 transformation products of TET were identified by UPLC-MS-TOF during the laccase-HBT oxidation process. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that LeLac12 could completely mineralize ring-cleavage products. LeLac12 completely catalyzed 50â¯mg/L TET within 4â¯h by adding AG (200â¯mg/L), while the degradation of AG was above 96% even in the co-contamination system. Proteomic analysis revealed that central carbon metabolism, energy metabolism, and DNA replication/repair were affected by TET treatment and the latter system could contribute to the formation of multidrug-resistant strains. The results demonstrate that LeLac12 is an efficient and environmentally method for the removal of antibiotics and dyes in the complex polluted wastewater.
Assuntos
Biodegradação Ambiental , Corantes , Lacase , Proteômica , Cogumelos Shiitake , Tetraciclina , Lacase/metabolismo , Lacase/genética , Tetraciclina/toxicidade , Tetraciclina/farmacologia , Corantes/toxicidade , Corantes/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Bacillus subtilis/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Antibacterianos/toxicidade , Antibacterianos/farmacologiaRESUMO
The global food waste problem, especially aquatic product spoilage, stimulates the accurate freshness analysis of food products. However, it still remains a great challenge to realize in-field determination of fish freshness at the time of use. In the present study, a colorimetric enzyme biosensor was developed for one-step detection of hypoxanthine (Hx), which is an important intermediate of adenosine triphosphate decomposition during fish storage. We demonstrate that xanthine oxidase grade I ammonium sulfate suspension (XOD-ASS) possesses peroxidase activity. It can oxidize different peroxidase substrates, including 3,3',5,5'-tetramethylbenzidine, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, and o-phenylenediamine in the presence of H2O2, producing visible color reactions. Further experiments indicate that XOD-ASS displayed effective peroxidase activity and could be used for H2O2 detection. Based on this, a one-step Hx detection method was established using only XOD-ASS as the catalyst. The method displays a good linear relationship in the range from 20 to 100 µM with a detection limit of 6.93 µM. Additionally, we successfully applied this method in testing Hx accumulation in sea bass fish samples of different storage times. The recovery values range from 97.44 to 102.56%. It is exciting to note that, compared with other methods, our proposed method provides a robust advantage on the economic reaction system, ease of preparation, short time consumption, and moderate reaction temperature. We believe that this method shows good application prospects for on-site fish freshness determination.
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INTRODUCTION: Walkability continues to attract great attention from urban planners, designers, and engineers as they recognize not only the merits of pedestrian facilities in terms of the health benefits but also their demerits in terms of accident risk to pedestrians. Wide footpaths improve the pedestrian environment and experience, and thereby motivate travelers to walk as much as possible. However, if footpaths are too wide, they may leave a smaller space for the roadway. On the other hand, wide road lanes may lead to higher road vehicle safety but are costly to construct and maintain and also may leave little space for the footpath. Evidently, for a fixed urban space, what is needed is an optimal balance between the vehicle lane and pedestrian path. This problem is encountered routinely in dense cities including Hong Kong where land availability is severely limited. METHOD: To address the issue, this paper first establishes safety performance functions (SPFs) for the pedestrian space and the road space, using the random-parameter negative binomial regression. The results indicate the extent to which road lane and footpath width changes are associated with changes in in-vehicle occupant and pedestrian casualties. Then the paper uses the SPFs to develop a methodology for optimizing the width allocations to the road lanes and footpaths, duly considering the user (safety) costs and agency (construction) costs associated with each candidate allocation of the widths. Finally, the paper analyzes the sensitivity of the optimal solution to the relative weights of user cost and agency cost. RESULTS: When user and agency costs are considered equally important, the optimal lane width is 5.4â¯m. CONCLUSION: It is observed that the road space allocation ratio used by the Hong Kong road agency suggests that the agency places a higher weight to user cost compared to agency cost. Practical Application: The findings can help incorporate design-safety relationships, and the stakeholders (agency and users) perspectives in urban road and footpath design.
Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Planejamento Ambiental/estatística & dados numéricos , Pedestres/estatística & dados numéricos , Segurança/estatística & dados numéricos , Cidades , Hong Kong , CaminhadaRESUMO
Speeding has been a great concern around the world due to the occurrence and severity of road crashes. This paper presents an evaluation of the effectiveness of different penalty and camera-based enforcement strategies in curbing speeding offences by professional drivers in Hong Kong. A stated preference survey approach is employed to measure the association between penalty and enforcement strategies and drivers' speed choices. Data suggest that almost all drivers comply with speed limits when they reach a camera housing section of the road. For other road sections, a panel mixed logit model is estimated and applied to understand the effectiveness of penalties and enforcement strategies on driver's speeding behaviors. Driving-offence points (DOPs) are found to be more effective than monetary fines in deterring speeding offences, albeit there is significant heterogeneity in how drivers respond to these strategies. Warning drivers of an upcoming camera-based enforcement section increased speed compliance. Several demographic and employment characteristics, driving history and perception variables also influence drivers' choices of speed compliance. Finally, besides penalty and enforcement strategies, driver education and training programs aimed at addressing aggressiveness/risk-taking traits might help reduce repeated speeding offences among drivers.
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Acidentes de Trânsito/estatística & dados numéricos , Condução de Veículo/legislação & jurisprudência , Controle Social Formal/métodos , Acidentes de Trânsito/prevenção & controle , Condução de Veículo/estatística & dados numéricos , Feminino , Hong Kong , Humanos , Modelos Logísticos , Masculino , SegurançaRESUMO
This retrospective consecutive case series aimed to evaluate spectral-domain optical coherence tomography (SD-OCT) for occult macular disease recognition preoperatively in patients scheduled for routine cataract surgery. All patients scheduled for cataract surgery underwent macular SD-OCT. Scans were reviewed for retinal, retinal pigment epithelium and vitreomacular interface abnormalities. For the subgroup analysis, the following information was collected: age; sex; and diabetes, hypertension, myopia, glaucoma, post intra-ocular surgery, endophotocoagulation, retinal vasculopathy and uveitis statuses. One-thousand-one-hundred-seventy-six consecutive scans were acquired from 1,176 patients. Macular pathology was found in 294 eyes. The most common macular disorders were an epiretinal membrane (n = 130), myopia atrophy (n = 61) and a dome-shaped macular with pathologic myopia (n = 32). One-hundred-thirty eyes (11.05%) presented macular epiretinal membranes not detected by dilated fundus examination, accounting for 44.22% of the abnormalities in diseased eyes and was higher than in previous Chinese studies. Some had multiple macular disorders. The most common ocular history was myopia, including high myopia. The pooled prevalence rate of macular diseases detected by OCT was 0.24 (95% CI 0.14-0.34) using meta-analysis. SD-OCT should be performed for routine cataract surgery patients to evaluate visual outcomes, especially in myopic patients and those considering advanced-technology intraocular lenses.
Assuntos
Extração de Catarata , Macula Lutea/diagnóstico por imagem , Tomografia de Coerência Óptica , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Catarata/epidemiologia , Extração de Catarata/métodos , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pré-Operatório , Doenças Retinianas/diagnóstico por imagem , Doenças Retinianas/epidemiologia , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodosRESUMO
The purpose of the present study was to investigate the vascular flow density (VD) of macular superficial (SCP), deep capillary plexus (DCP), and choriocapillaris and the size of the foveal avascular zone (FAZ) area in healthy children using optical coherence tomography angiography (OCTA). The potential associations of age, sex, intraocular pressure, body mass index, spherical equivalent, and axial length with OCTA parameters were also investigated. A total of 75 eyes from 75 healthy children were included for analysis, with the mean age 11.51 ± 1.91 years (range, 8-16 years). At the level of the SCP, mean VD and mean FAZ area were, respectively, 54.29 ± 2.25% and 0.290 ± 0.109 mm2. At the level of the DCP and choriocapillaris, mean VD were 60.19 ± 1.76% and 66.58 ± 1.33%, respectively. After adjustment on the signal strength index, there was no significant correlation between age and all OCTA parameters. Intra-observer repeatability was 0.91, 0.82, and 0.88 in the SCP, DCP and choriocapillaris, respectively. In healthy eyes of children, only sex has a significant influence on the FAZ area. OCTA may provide a noninvasive and reliable approach for evaluating macular perfusion in children, although sex-related variations should be considered.
Assuntos
Macula Lutea/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Adolescente , Criança , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Variações Dependentes do Observador , Imagem Óptica/métodos , Reprodutibilidade dos Testes , Fatores SexuaisRESUMO
The contents of chemical elements (Cd, Cr, Cu, Pb and Zn) in 11 kinds of crop/vegetables and soils around the Huodehong lead-zinc mining area in Yunnan, Southwest China were determined by using inductive coupled plasma emission spectrometry (ICP-MS). Results showed that element contents in soils decreased in the order of Zn > Pb > Cr > Cu > Cd. The high geo-accumulation indexes (Igeo) showed that cultivated soils near mine were practically polluted by Cd, Pb and Zn. The contents of Cd, Cr and Pb in crop/vegetables samples were significantly higher than the maximum permissible standard set by China. The potential health risk assessments among local residents were evaluated by the hazard index (HI), the total carcinogenic risk (TCR), the target hazard quotient (THQ) and carcinogenic risk (CR), respectively. The results showed that diet was the dominant exposure pathway. The results of HI for adult and child were 6.21 and 6.08, respectively. TCR values of Cr and Cd were more than 10-4. The THQ decreased in the following order: Cd > Pb > Cu > Zn > Cr. Among all kinds of crop/vegetables, leafy-vegetables were the major source of Cd and Pb exposure, root-vegetable were the important factors for Cu and Zn exposure, but tuber-vegetable were the factors for Cr exposure. The contents of Cd and Pb in human scalp hairs near Huodehong mine were higher than that in S20km area. Females possessed a higher risk for Cd, Cr, Cu and Pb exposure than males in study area. Significant differences between ages were found for Cd, Cu and Pb (p < 0.01). This study provided a powerful basis for the coordination of local environmental protection and economic sustainable development and assessing chemical elements risk to human health.
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Contaminação de Alimentos/análise , Metais Pesados/análise , Poluentes do Solo/análise , Verduras/química , Adulto , Criança , China , Monitoramento Ambiental/métodos , Feminino , Cabelo/química , Humanos , Masculino , Mineração , Medição de RiscoRESUMO
OBJECTIVE: To study the relationship between socioeconomic status (SES) and esophageal squamous cell carcinoma (ESCC) in Taixing city,Jiangsu province. METHODS: A population-based case-control study was carried out to collect data including demography, socioeconomic status indicators and possible risk factors. Unconditional logistic regression was used to compare different SES indicators and composite wealth scores constructed between cases and controls, using the principal component analysis methodology. RESULTS: Factors as:having received high school or higher education (OR = 0.66, 95% CI:0.46-0.96), living space over 67 m2 per-capita (OR = 0.71, 95% CI: 0.54-0.94), drinking tap water longer than 5 years (OR = 0.76, 95% CI:0.59-0.98) and wealth score >0.93 (OR = 0.63, 95%CI:0.48-0.83)were associated with increased risk of ESCC. Compared to those worked in farming, forestry, animal husbandry, fishery and water conservancy, the individuals who worked in business-service industry were at lower risk of ESCC(OR = 0.65, 95%CI:0.43-0.97). CONCLUSION: An inverse association of low SES and ESCC were found in Taixing people that called for further explanation.