ABSTRACT
Food-borne pathogens pose great risks to human health and public safety, and the formation of biofilm exacerbates their pathogenicity and antimicrobial resistance. Enzymes can target special substances in the biofilm to disintegrate the biofilm of food-borne pathogens, which has great potential for applications. This review summarized the progress of using enzymes to disintegrate the biofilms of food-borne pathogens, highlighting quorum-quenching enzymes, C-di-GMP metabolic enzymes, as well as extracellular matrix hydrolases. Finally, challenges and perspectives on developing enzymes into effective products for disintegrating the biofilms of food-borne pathogens were discussed.
Subject(s)
Humans , Biofilms , Quorum SensingABSTRACT
Objective@#To investigate the association between sedentary bouts and cardiovascular disease (CVD) risk factors, and to provide a reference for controlling and reducing the incidence of CVD in children.@*Methods@#Cluster random sampling was used to select 356 students from five primary schools in Guangzhou. Sedentary behavior and physical activity were assessed using ActiGraph GT3X accelerometers, which were worn for 7 consecutive days. According to the sedentary bout duration of each participant, sedentary time was classified into categories of 1-<5, 5-<10, 10-<15, 15-<20 and ≥20 min bouts. Physical examinations were carried out to identify cardiometabolic risk factors. Multivariate linear regression was performed to analyze the relationship between sedentary bouts and CVD risk factors.@*Results@#After adjusting for confounding factors, the time accumulated in sedentary bouts of 5-<10, 10-<15, 15-<20 min in duration were positively associated with higher cardiometabolic risk scores ( B =1.24， 2.01 ，2.40), negatively associated with lower HDL ( B =-0.13，-0.21，-0.27). The time accumulated in sedentary bouts of 1-<5, 5-<10 , 10-<15, 15-<20 min in duration were positively associated with BMI levels ( B =1.07，1.89，2.86，3.65), and waist circumference ( B =2.79，4.81，8.04，10.14)( P <0.05).@*Conclusion@#These results suggested that sedentary bouts of 5-<20 min were associated with an unfavorable cardiometabolic risk profile. Our finding suggests no more than 20 min accumulated sedentary time for children.
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Objective@#To investigate the prevalence of metabolic syndrome (MS) and to explore the relationship of MS with screen time (ST) among children aged 6-13 years in Guangzhou, China.@*Methods@#A total of 4 523 children aged 6-13 from 5 primary schools in Guangzhou were selected using stratified random cluster sampling method. Questionnaire was used to assess children’s basic demographic characteristics and ST. Children’s height, weight, waist circumference and blood pressure were measured objectively, and their blood glucose, triglyceride and high-density lipoprotein-cholesterol were tested. -Chi-square test was performed to compare the prevalence of MS in children among different ST levels. Logistic regression model was used to explore the association between ST and MS.@*Results@#The prevalence of MS in children was 2.4%, and that among boys (3.0%) was higher than in girls (1.7%, P=0.01). children were classified into three groups according to duration of ST: low ST (less than 1 h), moderate ST (1-2 h), high ST (higher than 2 h, 9.0% of total participants). Prevalence of central obesity, triacylglycerol and MS in high ST group was significantly higher than children with low ST(P<0.05). Children with high level of ST showed higher risks of central obesity (OR=1.43, 95%CI=1.04-1.96) and MS (OR=1.94, 95%CI=1.11-3.40) compared with low-level ST group.@*Conclusion@#Higher level of screen time associates with an increased risk of MS in children, which suggest the importance of effective early intervention.
ABSTRACT
We evaluated the tolerance and pathogenesis of foodborne pathogens with a simulated gastro-intestinal tract model that simulates the chemical, physical and biological effects of human digestion process under laboratory conditions. This could be used to study the tolerance, pathogenesis, gut microbiota interaction and vaccine development of foodborne pathogens, so as to contribute to control and treatment of foodborne pathogens. This review introduces the applications of simulated gastro-intestinal tract model tp evaluate foodborne pathogens, which includes in-vitro static gastro-intestinal model, in-vitro dynamic gastro-intestinal model, conventional animal model and humanized animal model. And the concepts and characteristics of all models are described in detail. Also, the shortcomings of existing models are analyzed, and improvements of artificial gastro-intestinal tract model are prospected. In conclusion, this review could provide comprehensive data for promoting the progress of studying tolerance and pathogenesis of foodborne pathogens.
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Objective To investigate the effect of rapid eye movement (REM) sleep deprivation on spatial memory and hippocampal cellular prion protein (PrPC) expression and to explore the underlying mechanism of cognitive impairment induced by sleep deprivation.Methods Adult Sprague-Dawley rats were sorted by weight,randomly divided into three groups:the cage control (CC) group,the tank control (TC) group,and the sleep deprivation (SD) group.Rats were deprived of REM sleep for 72 h using the modified multiple platform method.The Morris water maze task was used to assess hippocampal-dependent spatial memory.After sleep deprivation,the rats were sacrificed and their brain tissue was analyzed for PrPC protein expression via Western blotting.Hippocampal neuron axon elongation was examined as well after lentivector-mediated RNA interference (RNAi) of PrPC in primary cultured rat hippocampal neurons.Results REM sleep deprivation for 72 h resulted in spatial memory impairment.The number of times of rats passing through the platform was decreased significantly in the SD group (3.17 ±0.95) compared with the CC (7.17 ±0.95) and TC (6.50 ±0.62) groups (Z =2.026 6,Z =2.026 6,P ＜0.05),the mean value of proximity to the platform (mm) was greater for rats of the SD group (711.74 ± 33.99) compared to those of theCC (592.32±31.31) andTC (580.86±11.36) groups (Z=-2.001 6,Z=-2.4820,P ＜ 0.05).REM sleep deprivation for 72 h resulted in reduced PrPC level in the hippocampus (0.33 ± 0.10) compared with the CC (1.01 ±0.33) and TC (0.96 ±0.27) groups (Z=2.152 9,Z=2.152 9,P ＜ 0.05).In primary cultured hippocampal neurons,axon elongation(μm) was inhibited 7 days in infected neurons (326.28 ± 12.53) compared with normal (555.00 ±30.43) or negative control (558.70 ±23.10) cells (Z =4.768 4,Z =4.877 0,P ＜ 0.05).Conclusion These findings suggest that PrPC-mediated hippocampal neuron axon elongation inhibition is probably involved in spatial memory impairment induced by sleep deprivation in rats.