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1.
J Environ Manage ; 356: 120632, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38531129

RESUMO

To provide a sufficient supply of electron donors for the synthesis of caproic acid, yeast fermentation was employed to increase ethanol production in the anaerobic fermentation of Chinese cabbage waste (CCW). The results showed that the caproic acid yield of CCW with ethanol pre-fermentation was 7750.3 mg COD/L, accounting for 50.2% of the total volatile fatty acids (TVFAs), which was 32.5% higher than that of the CCW without yeast inoculation. The synchronous fermentation of yeast and seed sludge significantly promoted the growth of butyric acid consuming bacterium Bacteroides, resulting in low yields of butyric acid and caproic acid. With yeast inoculation, substrate competition for the efficient ethanol conversion in the early stage of acidogenic fermentation inhibited the hydrolysis and acidfication. Without yeast inoculation, the rapid accumulation of TVFAs severely inhibited the growth of Bacteroidetes. In the reactor with ethanol pre-fermentation, the key microorganism for caproic acid production, Clostridium_sensu_stricto_12, was selectively enriched.


Assuntos
Brassica , Microbiota , Fermentação , Caproatos , Saccharomyces cerevisiae , Anaerobiose , Ácidos Graxos Voláteis , Esgotos/química , Butiratos , Etanol , Concentração de Íons de Hidrogênio , Reatores Biológicos
2.
Food Res Int ; 178: 113946, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38309871

RESUMO

Chemical hazards in foods, especially naturally occurring food contaminants like mycotoxins, are of serious public health concern. It is important to develop a practical framework to assess and rank health risks of chemical contaminants which can be further utilized by regulatory agencies to prioritize resources for risk assessment and management. In this study, a tiered hazard-prioritization and risk-ranking approach, which included two steps: exposure-based screening and margin of exposure (MOE)-based probabilistic risk ranking; was proposed to efficiently identify and rank chemicals of health concerns. Given the exposure-based hazard prioritization, chemicals with negligible or low health risks were first excluded. The remaining chemicals, imposing a higher health risk, were then ranked to facilitate risk-based decision making. The proposed approach was applied to identify and rank the mycotoxins with substantial health concerns in food commodities randomly sampled in China. A total of 19 mycotoxins were analyzed in 783 food commodities, including infant cookie, noodle, rice flour samples, wheat flour, millet, and rice. Results showed that the mycotoxins in infant foods with the highest health risk were Tenuazonic acid, Deoxynivalenol, and Enniatin B1, but as indicated by the probabilistic MOE estimation, the risks were still in the acceptable range and generally lower than the risks imposed by trace elements (e.g., Arsenic and Cadmium). The health risks of the other 16 mycotoxins were negligible mainly due to their low exposure levels. This study demonstrated that the proposed tiered approach was an efficient and effective tool to quantify and prioritize health risks in support of human health risk management.


Assuntos
Micotoxinas , Lactente , Humanos , Micotoxinas/análise , Farinha , Contaminação de Alimentos/análise , Triticum , Medição de Risco/métodos
3.
J Biotechnol ; 381: 1-10, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38176540

RESUMO

The effects of hydraulic retention time (HRT) on the performance of two-phase anaerobic fermentation for caproic acid production from Chinese cabbage waste (CCW) were investigated. In the electron donor phase, yeast was inoculated to achieve efficient autopoietic ethanol, providing electron donors for the chain elongation process. Shorter HRT led to drastic fluctuations in microorganisms, thus resulting in lower acid yields at HRT of 6 days. At HRT of 10 days, the balanced collaboration of various key bacteria avoided the accumulation of intermediate by-products, and the caproic acid production reached 4660 mg COD/L, which was 119.5% and 154.8% higher than that at HRTs of 6 and 14 days, respectively. At HRT of 14 days, the low ethanol loading rate resulted in ethanol excessive-oxidation to acetic acid. Acetic acid accounted for 41.5% of the total product, while the selectivity of caproic acid was only 15.3%. The main contributor to the production process of caproic acid was Caproiciproducens, while the Ruminalococcaceae also played a role in the process. This study provided a theoretical basis for the efficient production of caproic acid through continuous fermentation with autopoietic electron donors.


Assuntos
Reatores Biológicos , Caproatos , Elétrons , Fermentação , Reatores Biológicos/microbiologia , Anaerobiose , Ácido Acético , Etanol
4.
Heliyon ; 9(11): e21814, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38027797

RESUMO

The aim of this study was investigate the spatial effects of A-class scenic spots and the spatial distribution of highway networks on the influence of self-driving tour behavioral patterns in China at the urban agglomeration scale, based on big data of road traffic during three holidays. A spatial analysis method and a geographically weighted regression model were used to analyze the spatial distribution differences and influencing factors of self-driving tourism flows in the central Yunnan urban agglomeration. The results showed that holiday self-driving tourism in the central Yunnan urban agglomeration presented a typical core-edge spatial pattern. The mean value of the spatial autocorrelation coefficient was 0.54, indicating significant spatial autocorrelation. The influence of tourism resources and traffic conditions on self-driving tourism flow showed a decreasing trend from the center of the high positive value to the periphery of the main urban area of Kunming. This study reveals the spatial differentiation characteristics of self-driving tourism flows in urban agglomerations and lays a theoretical foundation for understanding flow pattern.

5.
Accid Anal Prev ; 193: 107287, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37729750

RESUMO

Understanding how built environment are associated with crash risk (CR) in school commuting is essential to improving travel safety through land use and transportation policies. Scholars often assume that this relationship is consistent across space, but this may lead to inconsistent estimates. To address this issue, using data in Shenzhen, China, the data covers traffic accident data of children taken from police incident reports and supplemented with local land use, transportation network and specific school information. The measurement model of crash scale was conducted to represent crash severity, and the CR was further quantified. The study applies three models, spatial dubin model (SDM), geographically weighted regression (GWR), and mixed GWR (MGWR), to explore spatio-temporal heterogeneity relationships between built environment attributes and CR of children in school commuting. The findings reveal that the crash scale can better represent crash severity of school commuting than a single indicator. Policy interventions should be targeted at specific spatial scales, school types, and time windows to effectively improve travel safety. However, there are some common findings. It is recommended to use a scale of 200 m to explain the relationship between the variables. The MGWR model outperforms the other two models. To reduce CR, it is important to consider lower road network density, a reasonable layout of educational facilities, fewer bus routes, and more on-street parking spaces. Our findings can help to enrich the understanding of associations between land use and CR of children, as well as offer local planning and operating guidance for creating child-friendly environment.

6.
Toxins (Basel) ; 15(6)2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37368690

RESUMO

Wheat grains are susceptible to contamination with various natural mycotoxins including regulated and emerging mycotoxins. This study surveyed the natural presence of regulated mycotoxins, such as deoxynivalenol (DON) and zearalenone (ZEN), and emerging mycotoxins such as beauvericin (BEA), enniatins (ENNs such as ENA, ENA1, ENB, ENB1) and Alternaria mycotoxins (i.e., alternariol monomethyl ether (AME), alternariol (AOH), tenuazonic acid (TeA), tentoxin (TEN), and altenuene (ALT)) in wheat grains randomly collected from eight provinces across China in 2021. The results revealed that each wheat grain sample was detected with at least one type of mycotoxin. The detection rates of these mycotoxins ranged from 7.1% to 100%, with the average occurrence level ranging from 1.11 to 921.8 µg/kg. DON and TeA were the predominant mycotoxins with respect to both prevalence and concentration. Approximately 99.7% of samples were found to contain more than one toxin, and the co-occurrence of ten toxins (DON + ZEN + ENA + ENA1 + ENB + ENB1 + AME + AOH + TeA + TEN) was the most frequently detected combination. The dietary exposure to different mycotoxins among Chinese consumers aged 4-70 years was as follows: 0.592-0.992 µg/kg b.w./day for DON, 0.007-0.012 µg/kg b.w./day for ZEN, 0.0003-0.007 µg/kg b.w./day for BEA and ENNs, 0.223-0.373 µg/kg b.w./day for TeA, and 0.025-0.041 µg/kg b.w./day for TEN, which were lower than the health-based guidance values for each mycotoxin, with the corresponding hazard quotient (HQ) being far lower than 1, implying a tolerable health risk for Chinese consumers. However, the estimated dietary exposure to AME and AOH was in the range of 0.003-0.007 µg/kg b.w./day, exceeding the Threshold of Toxicological Concern (TTC) value of 0.0025 µg/kg b.w./day, demonstrating potential dietary risks for Chinese consumers. Therefore, developing practical control and management strategies is essential for controlling mycotoxins contamination in the agricultural systems, thereby ensuring public health.


Assuntos
Micotoxinas , Zearalenona , Micotoxinas/análise , Triticum , Exposição Dietética/efeitos adversos , Contaminação de Alimentos/análise , Espectrometria de Massas em Tandem/métodos , Zearalenona/análise , Ácido Tenuazônico/análise , China , Alternaria
7.
J Food Sci ; 88(8): 3607-3618, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37326343

RESUMO

We investigated the occurrence of 80 pesticide residues in 96 honey samples from apiaries with honeybee poisoning incidences by liquid chromatography-tandem mass spectrometry and subsequently conducted risk assessments of exposure for in-hive honeybees and Chinese consumers. Six pesticides were detected with residue concentrations ranging from 0.5 to 130.9 µg/kg. The mean concentrations of acetamiprid, dinotefuran, hexythiazox, propargite, semiamitraz, and carbendazim in positive samples were 7.9 ± 9.1, 5.9 ± 1.7, 3.0 ± 1.6, 44.2 ± 50.0, 9.0 ± 9.4, and 5.5 ± 4.1 µg/kg, respectively. Carbendazim, semiamitraz, and acetamiprid were the major contaminants in honey, with incidences of 99.0%, 93.8%, and 49.0%, respectively. The cooccurrence of pesticides (≥2 pesticides) was detected in 95.9% of the samples, with up to six residual pesticides found in one sample. The HQ (hazard quotient) values of the six pesticides to in-hive honeybees were from 4.7 × 10-8 to 0.021, less than 1, indicating their acceptable exposure risk to honeybees. In terms of the representative-case and worst-case scenarios, the sum of separate HQs of each pesticide yielding an HI (hazard index) ranged from 0.012 to 0.016 for in-hive worker honeybees and from 0.015 to 0.021 for in-hive larva honeybees, indicating an overall acceptable potential cumulative risk of multiple pesticides to in-hive honeybees. Both the %ARfD (acute reference dose) value (0.0001-0.075) and %ADI (acceptable daily intake) value (0.00002-0.0046) of risky pesticides were much less than 100, revealing acceptable risk exposure to risky pesticides via honey consumption for human health. Thus, our results showed that multipesticide residual honey from apiaries with honeybee poisoning incidents in East China was safe for humans and in-hive honeybees. PRACTICAL APPLICATION: This analytical approach will be used in detecting multiple pesticide residues in honey and risk assessment for dietary exposure to pesticide residues. It can support various surveillance programs about honey safety and in-hive honeybee health evaluation.


Assuntos
Mel , Resíduos de Praguicidas , Praguicidas , Abelhas , Animais , Humanos , Resíduos de Praguicidas/toxicidade , Resíduos de Praguicidas/análise , Mel/análise , População do Leste Asiático , Praguicidas/análise , Espectrometria de Massas em Tandem , Medição de Risco
8.
Food Chem ; 402: 134487, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36303385

RESUMO

A multi-functional nanoflares biosensor of spherical gold nanoparticle (Au NP) modified by fluorophore-labeled oligonucleotides (ONS) was designed for ultra-sensitive multi-target mycotoxin analysis in food. Au NP was densely modified with multiplex highly oriented hairpins of oligonucleotides (ONS), each ONS was hybridized to a reporter with a distinct fluorophore label and specifically affiliative to its corresponding mycotoxin target. The fluorescent signals of reporters were pre-quenched by Au NP based on ONS hairpin structures and recovered when exposed to ONS's targets. Excitation-emission matrix (EEM) fluorescence detection was performed in EX and EM wavelength of 200-800 nm. Heavily overlapping spectra of fluorophores, mycotoxins and backgrounds were resolved by alternative trilinear decomposition (ATLD) algorithm, pure spectra of specific fluorophore responding to mycotoxin target can be extracted out for quantitative analysis. Four mycotoxins (Aflatoxin B1, zearalenone, Fumonisins B1, ochratoxin A) were simultaneously quantified at extremely low level with limit of detection <0.02 µg kg-1, the average recovery accuracies were higher than 91.7 % in various matrices of cereals, nuts, edible oils. This study realized an important breakthrough of the application of nanoflares biosensor and maybe promising to be as an alternative strategy for onsite mycotoxins monitoring of food.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Micotoxinas , Micotoxinas/análise , Ouro/química , Nanopartículas Metálicas/química , Oligonucleotídeos , Contaminação de Alimentos/análise
9.
J Biomater Appl ; 37(7): 1169-1181, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36189748

RESUMO

The rapid development of flexible electronic technology has led to the in-depth study of flexible wearable sensors to achieve accurate sensing under different external stimuli. However, it is still a huge challenge to develop hydrogel-based wearable skin-like sensors with super ductility, high sensitivity, and self-healing properties. Herein, the Ti3C2 type of MXene was synthesized, and the Ag/MXene nanocomplexes were incorporated into polyvinyl alcohol-borax matrix to construct a novel composite hydrogel as the multifunctional nanofillers, which could bring both improved properties and novel functionalities. The Ag/MXene-Poly (vinyl alcohol) (PVA) hydrogel displayed integrated merits of highly strain sensitive (GF = 3.26), self-healing (within 10 min, 91% healing efficiency), and excellent antibacterial activity. The hydrogel could be assembled into a wearable skin-like sensor to monitor human movement, including large deformations (finger, elbow, wrist, and knee bending) and tiny deformations (mouth's movement and throat vocalization) in real time. Therefore, this work shed a new light on the development of flexible wearable skin-like sensors for the personalized healthcare monitoring, human-machine interfaces, and artificial intelligence.


Assuntos
Hidrogéis , Dispositivos Eletrônicos Vestíveis , Humanos , Inteligência Artificial , Antibacterianos , Condutividade Elétrica
10.
Int J Food Microbiol ; 381: 109912, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36081243

RESUMO

Florfenicol, an animal-specific broad-spectrum antibiotic, has been widely used in livestock and poultry breeding, which leads to the high antimicrobial resistance (AMR) of Campylobacter in food animals. Recently, a new florfenicol resistance gene, fexA, often located on various multidrug resistance genomic islands (MDRGIs) and confers resistance to various antimicrobial agents, was characterized in Campylobacter. However, the prevalence and genetic environments of fexA and its associated MDRGIs in Campylobacter in the poultry supply chain need further characterization. Here, a total of 111 (15.48 %) Campylobacter isolates (63 C. jejuni, 40 C. coli, 8 C. lari) were obtained from 717 samples from farms, slaughterhouses, and supermarkets. Both phenotypic and genotypic analyses indicated that the AMR of C. coli was significantly higher than that of C. jejuni. PCR amplification and whole genome sequencing showed that the fexA gene was present in 26 out of 35 florfenicol-resistant Campylobacter isolates. This gene was located in the tet(L)-fexA-tet(O) MDRGI. The fexA-harboring isolates detected in the above sources could be clustered into the same branch, indicating that they may have the same ancestor. In addition, the erm(B) gene was identified in 17 Campylobacter isolates, and the A2075G point mutation in the 23S rRNA gene occurred in 26 isolates, emphasizing the high resistance of Campylobacter to macrolides. In summary, these results indicate that fexA within the MDRGI of Campylobacter can be transmitted through bacteria in the animal-based food supply chain, and it is necessary to strengthen the monitoring of the prevalence and spread of fexA in foodborne Campylobacter spp.


Assuntos
Anti-Infecciosos , Infecções por Campylobacter , Campylobacter coli , Campylobacter jejuni , Campylobacter , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Campylobacter/genética , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/genética , Farmacorresistência Bacteriana/genética , Macrolídeos , Testes de Sensibilidade Microbiana , Aves Domésticas/microbiologia , Prevalência , Tianfenicol/análogos & derivados
11.
AMB Express ; 12(1): 115, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36066652

RESUMO

ß-1,3/1,6-glucan as a prebiotic improves immune performance in animals. These functions are closely related to the effect of ß-1,3/1,6-glucan on gut microbiota structure. However, the effect of ß-1,3/1,6-glucan on the gut microbiota structure of broilers is unclear. The aim of this study was to confirm the effects of ß-1,3/1,6-glucan on the cecal microflora structure of yellow-feathered broilers. This study monitored the antimicrobial resistance (AMR) level of Escherichia coli in feces of yellow-feathered broilers by standard broth dilution method and mastered the AMR level of chickens selected. The effects of ß-1,3/1,6-glucan on gut microbiota were investigated by 16S rRNA sequencing. The results showed that the number of isolated multidrug-resistant E. coli strains accounted for 98.41%. At 14, 21, and 28 days of age, supplemented of 0.2%, 0.1%, and 0.1% ß-1,3/1,6-glucan in yellow-feathered broiler diets significantly altered gut microbial composition, and beneficial bacteria Alistipes, Bacteroides and Faecalibacterium were significantly increased. These findings provide guidance and recommendations for ß-1,3/1,6-glucan as a broiler feed additive to improve the growth of broilers.

12.
Microbiol Spectr ; 10(4): e0201522, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-35950758

RESUMO

Widely distributed multidrug-resistant (MDR) bacteria threaten animals and human health. Nevertheless, few antimicrobial resistance (AMR) surveys of large-scale animal-derived bacteria have been explored. Here, 1,468 (97.54%) Escherichia coli strains were isolated from 1,505 pig (1,060) and chicken (445) anal swab samples from 11 cities in Zhejiang Province, China, in 2020. These isolates had a high resistance to tetracycline (92.92%), sulfisoxazole (93.05%), florfenicol (83.11%), and ampicillin (78.27%). More than 88.68% of the strains were MDR bacteria. A low AMR ratio to the "last-resort" antimicrobials tigecycline (0.75%), colistin (1.36%), and meropenem (0.75%) were found. The AMR of E. coli from pigs was higher than that of chickens. Eighteen strains among 31 MDR strains that were resistant to "last-resort" antimicrobials could transfer the AMR genes (mcr-1, tet(X), and blaNDM) to the recipient strain J53, which confer colistin, tigecycline, and carbapenem resistance, respectively. The homology among mcr-1-carrying isolates was relatively high, and the sequence types were mainly ST5529, ST101, and ST354, while the homology of isolates harboring tet(X4) and blaNDM-5 genes were different. The mcr-1, blaNDM-5, and tet(X4) genes in strains LS45, JH51, and TZ118 were identified on the Incl2, IncHI2, and IncX1 plasmids, respectively. Moreover, tet(A), sul2, floR, and blaTEM-1B were the most common ARGs in 31 strains. Additionally, the heavy metals copper and zinc had a significant correlation with amoxicillin/clavulanate and tetracycline resistance. Controlling the movement of animals between cities and reducing the use of antimicrobials are effective methods to reduce the threat of AMR bacteria. IMPORTANCE Pigs and chickens are the most common food animals that are the important vectors for spreading antimicrobial-resistant pathogens among animals and humans. Limited systematic AMR monitoring of these food animal origin bacteria had been reported, especially in developed areas of China. Our study provides a comprehensive and systematic study of AMR in Escherichia coli from eastern China. The AMR of E. coli strains among the animals or cities has statistically significant differences. Moreover, the mcr-1, tet(X4), and blaNDM-5 genes, considered resistant to the last line of AMR, were identified in part of farms. The transferability and the prevalence of these AMR strains were intensively studied. Our monitoring is comparable to human clinical research and has an essential reference for public health safety. These findings will provide early warning for AMR strains and guide the clinical use of antibiotics to control the spread of antibiotic resistance.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Animais , Antibacterianos/farmacologia , Galinhas , Colistina/farmacologia , Farmacorresistência Bacteriana/genética , Escherichia coli , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Humanos , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Suínos , Tigeciclina/farmacologia
13.
Front Microbiol ; 13: 885132, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935206

RESUMO

Antimicrobial resistance (AMR) may lead to worldwide epidemics through human activities and natural transmission, posing a global public safety threat. Colistin resistance mediated by the mcr-1 gene is the most prevalent among animal-derived Escherichia coli, and mcr-1-carrying E. coli have been frequently detected in central-eastern China. However, animal-derived E. coli with AMR and the prevalence of mcr-1 in the Qinghai Plateau have been rarely investigated. Herein, 375 stool samples were collected from 13 poultry farms in Qinghai Province and 346 E. coli strains were isolated, of which eight carried mcr-1. The AMR rates of the E. coli strains to ampicillin, amoxicillin/clavulanic acid, and tetracycline were all above 90%, and the resistance rates to ciprofloxacin, cefotaxime, ceftiofur, and florfenicol were above 70%. Multidrug-resistant strains accounted for 95.66% of the total isolates. Twelve E. coli strains showed colistin resistance, from which a total of 46 AMR genes and 36 virulence factors were identified through whole-genome sequencing. The mcr-1 gene resided on the IncHI2, IncI2-type and IncY-type plasmids, and mcr-1 was located in the nikA-nikB-mcr-1-pap2 gene cassette (three strains) or the pap2-mcr-1-ISApl1 structure (one strain). Completed IncI2-type plasmid pMCR4D31-3 sequence (62,259 bp) revealed that it may cause the horizontal transmission of mcr-1 and may increase the risk of its spread through the food chain. Taken together, the AMR of chicken-derived E. coli in the plateau is of concern, suggesting that it is very necessary for us to strengthen the surveillance in various regions under the background of one health.

14.
Toxins (Basel) ; 14(8)2022 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-35893751

RESUMO

Deoxynivalenol (DON) and emerging Alternaria toxins often co-occur in cereal-based products, but the current risk assessment is commonly conducted for only one type of mycotoxin at a time. Compared to adults, infants and young children are more susceptible to mycotoxins through food consumption, especially with cereal-based food products which are the main source of exposure. This study aimed to perform a probabilistic risk assessment of combined exposure to DON and three major Alternaria toxins, namely including alternariol monomethyl ether (AME), alternariol (AOH), and tenuazonic acid (TeA) through consumption of cereal-based foods for Chinese infants and young children. A total of 872 cereal-based food products were randomly collected and tested for the occurrence of DON and three major Alternaria toxins. The results on mycotoxin occurrence showed the DON, TeA, AOH, and AME was detected in 56.4%, 47.5%, 7.5%, and 5.7% of the samples, respectively. Co-contamination of various mycotoxins was observed in 39.9% of the analyzed samples. A preliminary cumulative risk assessment using the models of hazard index (HI) and combined margin of exposure (MoET) was performed on DON and Alternaria toxins that were present in cereal-based food products for infants and young children in China for the first time. The results showed that only 0.2% and 1.5%, respectively, of individuals exceeded the corresponding reference value for DON and TeA, indicating a low health risk. However, in the case of AME and AOH, the proportion of individuals exceeding the reference value was 24.1% and 33.5%, respectively, indicating the potential health risks. In the cumulative risk assessment of AME and AOH, both HI and MoET values indicated a more serious risk than that related to individual exposure. Further research is necessary to reduce the uncertainties that are associated with the toxicities of the Alternaria toxins and cumulative risk assessment methods.


Assuntos
Alternaria , Grão Comestível , Contaminação de Alimentos , Tricotecenos , Alternaria/isolamento & purificação , Pré-Escolar , China , Grão Comestível/química , Grão Comestível/microbiologia , Contaminação de Alimentos/análise , Humanos , Lactente , Lactonas/análise , Micotoxinas/análise , Medição de Risco , Ácido Tenuazônico/análise , Tricotecenos/análise
15.
J Microbiol ; 60(6): 610-619, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35362896

RESUMO

Considering the serious threat to food safety and public health posed by pathogens with colistin resistance, colistin was banned as a growth promoter in 2017 in China. In recent years, the resistance rate of Escherichia coli isolated from animal intestines or feces to colistin has decreased. However, the prevalence and characteristics of the mcr-1 gene in retail meat have not been well explored. Herein, 106 mcr-1-negative and 16 mcr-1-positive E. coli isolates were randomly recovered from 120 retail meat samples and screened using colistin. The 106 E. coli isolates showed maximum resistance to sulfafurazole (73.58%) and tetracycline (62.26%) but susceptibility to colistin (0.00%). All 16 mcr-1-positive E. coli isolates showed resistance to colistin, were extended spectrum beta-lactamase (ESBL)-positive and exhibited complex multidrug resistance (MDR). For these 16 isolates, 17 plasmid replicons and 42 antibiotic resistance genes were identified, and at least 7 antibiotic resistance genes were found in each isolate. Acquired disinfectant resistance genes were identified in 75.00% (12/16) of the isolates. Furthermore, comparative genomic and phylogenetic analysis results indicated that these 16 mcr-1-positive E. coli isolates and the most prevalent mcr-1-harboring IncI2 plasmid in this study were closely related to other previously reported mcr-1-positive E. coli isolates and the IncI2 plasmid, respectively, showing their wide distribution. Taken together, our findings showed that retail meat products were a crucial reservoir of mcr-1 during the colistin ban period and should be continuously monitored.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Animais , Antibacterianos/farmacologia , China , Colistina/farmacologia , Farmacorresistência Bacteriana/genética , Proteínas de Escherichia coli/genética , Carne/análise , Testes de Sensibilidade Microbiana , Filogenia , Plasmídeos/genética , Prevalência
16.
Food Chem ; 373(Pt B): 131512, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34772573

RESUMO

A novel composite material consisting of zirconiumbiphenyldicarboxylate metal-organic framework, graphite oxide and ferroferric oxide was fabricated by a facile one-step method and served as a magnetic solid phase extraction sorbent for the simultaneous determination of nitroimidazoles and benzimidazoles in honey. The amount of graphite oxide for the synthesis of composite material and analysis parameters were optimized. The optimum parameters were: dipotassium hydrogen phosphate buffer solution (pH 6) as diluent solvent, adsorption time 10 min, desorption time 5 min, methanol/acetonitrile (1:1, V/V) as desorption solvent. The targets were detected by ultra-high performance liquid chromatography tandem mass spectrometry. The recoveries of twelve analytes ranged in 70.5%-103.4% with relative standard deviations lower than 12.9% (n = 3). The quantification limits were 0.2-0.6 µg/kg. Using the composite material as sorbent, a simple, rapid and environmental-friendly method based on magnetic solid phase extraction was successfully developed for determination of seven nitroimidazoles and five benzimidazoles in honey.


Assuntos
Mel , Estruturas Metalorgânicas , Nitroimidazóis , Benzimidazóis , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Mel/análise , Fenômenos Magnéticos , Nitroimidazóis/análise , Extração em Fase Sólida , Espectrometria de Massas em Tandem
17.
Int Orthop ; 46(2): 215-222, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34448923

RESUMO

PURPOSE: Reconstruction of severe acetabular deficiency is extremely challenging in total hip arthroplasty (THA) revisions. Novel bispherical augments were designed to fill acetabular bone loss and facilitate restoration of hip center of rotation (HCOR). Current study aims to compare the outcomes of bispherical augments and tantalum augments. METHODS: Between July 2017 and December 2018, bispherical augments (BA group) were implanted in 25 patients (25 hips) and 22 patients (22 hips) underwent porous tantalum augments (TA group) reconstruction in revision THA. Clinical and radiographic results were evaluated for 25 hips in BA group and 20 hips in TA group at the final follow-up. The mean duration of follow-up was 2.9 years (range, 2.2 ~ 3.7) in BA group and 2.9 years (range, 2.3 ~ 3.8) in TA group. RESULTS: Harris hip scores, HCOR, and leg length discrepancy (LLD) correction did not differ between the treatment groups. The bispherical augments were located more closer to the medial-superior part (zone II) of acetabular shell while the majority of tantalum augments were located at the lateral-superior part (zone I) (P = 0.010). More screws were used in the BA group for augment fixation (mean 2.1 vs. 1.3) (P = 0.000). There was no evidence of loosening or migration in all hips. Only one dislocation occurred in BA group and treated with closed reduction, no recurrence of instability up to the final follow-up. CONCLUSION: The clinical and radiological outcomes of bispherical augments were comparable with tantalum augments; this technique was a reliable alternative method in severe acetabular deficiency reconstruction.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/métodos , Seguimentos , Prótese de Quadril/efeitos adversos , Humanos , Falha de Prótese , Reoperação , Estudos Retrospectivos , Resultado do Tratamento
18.
J Hazard Mater ; 423(Pt A): 126962, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34464866

RESUMO

Colorimetric and fluorescent methods for Ochratoxin A (OTA) detection are convenient and well received. However, the pigments and autofluorescence originated from food matrices often interfere with detection signals. We have developed a strategy with colorimetric and fluorescent dual modes to solve this challenge. In the colorimetric mode, OTA aptamer (AP9) was assembled into a DNA triple-helix switch with a specially designed signal-amplifying sequence. The OTA-induced G-quadruplex (G4) of AP9 would open the switch and release the signal-amplifying sequence for colorimetric signal amplification. The G4 structures of AP9 were further utilized to combine with the fluorogenic dye ThT for fluorescent mode. By skillfully engineering DNA G4 assembly for signal amplification, there was no need for any DNA amplification or nanomaterials labeling. Detections could be carried out in a wide temperature range (22-37 â„ƒ) and finished rapidly (colorimetric mode, 60 min; fluorescent mode, 15 min). Broad linear ranges (colorimetric mode, 10-1.5 ×103 µg/kg; fluorescent mode, 0.05-1.0 ×103 µg/kg) were achieved. The limit of detection for colorimetric and fluorescent modes were 4 µg/kg and 0.01 µg/kg, respectively. The two modes have been successfully applied to detect OTA in samples with intrinsic pigments and autofluorescence, showing their applicability and reliability.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Colorimetria , DNA , Limite de Detecção , Ocratoxinas , Reprodutibilidade dos Testes
19.
J BUON ; 26(4): 1239-1245, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34564976

RESUMO

PURPOSE: The purpose of this study was to research and validate techniques for extracting DNA from human genomes, explore the sensitivity and specificity of known nucleic acid markers of intestinal malignancy in Chinese patients with early colorectal cancer. We also tried to find adenoma-specific biomarkers in human DNA in feces. METHODS: We compared the ability of fecal DNA testing, Fecal Occult Blood Testing (FOBT) and serum tumor markers to diagnose different types of polyps, and DNA testing was significantly superior to the other two methods. We also found a dominant expression of NDRG12b methylation in multi-target DNA testing, which may be a promising marker for detection of colorectal precancerosis. RESULTS: The sensitivity of NDRG4 12b methylation was 85.7% for advanced adenomatous polyp (AP), and 62.6% for non-advanced AP, respectively, with specificity of 70.8%. The diagnostic efficacy of NDRG4 12b methylation for detecting advanced AP was significantly higher than FOBT (sesitivity: 85.7% vs. 42.9%, p<0.05). The receiver operating characteristics (ROC) curve for NDRG4 12b methylation in detecting AP showed a relatively high area under the curve (AUC = 0.807). CONCLUSIONS: Our results indicate that highly sensitive fecal DNA testing of NDRG4 12b methylation is a promising marker for detection of colorectal precancerosis, especially in detecting adenomatous polyp.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Metilação de DNA , DNA de Neoplasias/análise , Fezes/química , Proteínas Musculares/genética , Proteínas do Tecido Nervoso/genética , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/genética , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
20.
Nanotechnology ; 32(50)2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34544054

RESUMO

An all-dielectric periodic array is proposed to form plasmon lattice resonances (PLR). In the array, Si nanopillars are on top of SiO2nanopillars, and SiO2nanopillars are on top of quartz substrates. The simulated results show that the line-width of the PLR can be as small as 3.3 nm. This can be attributed to the coupling between the Mie resonances of Si nanopillars and the diffracted waves. While the PLR can't be formed by the periodic Si nanopillar array directly sitting on quartz substrates. The diameter and height of Si nanopillars, the period of the array and the height of SiO2nanopillars have significant impacts on the PLR. This work extends the application of PLR.

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