Rapid Nucleic Acid Detection of Listeria monocytogenes Based on RAA-CRISPR Cas12a System.

Listeria monocytogenes (L. monocytogenes) is a food-borne pathogenic bacteria that frequently contaminates animal-derived food and low-temperature preserved food. Listeriosis caused by its infection has a high mortality rate and poses a serious threat to human health. Therefore, it is crucial to establish a sensitive, rapid and easy-to-operate technique. In this study, a Recombinase Aided Amplification (RAA) assisted CRISPR/Cas12a (RAA-CRISPR/Cas12a) fluorescence platform was established for highly sensitive nucleic acid detection of L. monocytogenes. The established RAA-CRISPR/Cas12a showed high sensitivity and high specificity, with the sensitivity of 350 CFU/mL and 5.4 × 10-3 ng/µL for pure bacterial solution and genomic DNA, and good specificity for 5 strains of Listeria spp. and 14 strains of other common pathogenic bacteria. L. monocytogenes could be detected at an initial concentration of 2.3 CFU/25g within 2 h of enriching the beef in the food matrix, and this method could be applied to food samples that were easily contaminated with L. monocytogenes The results of RAA-CRISPR/Cas12a could be observed in 5 min, while the amplification was completed in 20-30 min. The speed and sensitivity of RAA-CRISPR/Cas12a were significantly higher than that of the national standard method. In conclusion, the RAA-CRISPR/Cas12a system established in this study has new application potential in the diagnosis of food-borne pathogens.

Effects of Flavourzyme and Alkaline Protease Treatment on Structure and Allergenicity of Peanut Allergen Ara h 1.

Research background: Peanut allergy poses a significant threat to human health due to the increased risk of long-term morbidity at low doses. Modifying protein structure to affect sensitization is a popular topic. Experimental approach: In this study, the purified peanut allergen Ara h 1 was enzymatically hydrolysed using Flavourzyme, alkaline protease or a combination of both. The binding ability of Ara h 1 to antibodies, gene expression and secretion levels of the proinflammatory factors interleukin-5 and interleukin-6 in Caco-2 cells was measured. Changes in the secondary and tertiary structures before and after treatment with Ara h 1 were analysed by circular dichroism and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Results and conclusions: The results indicated a decrease of the allergenicity and proinflammatory ability of Ara h 1. The evaluation showed that the Flavourzyme and alkaline protease treatments caused particle shortening and aggregation. The fluorescence emission peak increased by 3.4-fold after the combined treatment with both proteases. Additionally, the secondary structure underwent changes and the hydrophobicity also increased 8.95-fold after the combined treatment. Novelty and scientific contribution: These findings partially uncover the mechanism of peanut sensitization and provide an effective theoretical basis for the development of a new method of peanut desensitization.

Caffeic acid phenethyl ester suppresses intestinal FXR signaling and ameliorates nonalcoholic fatty liver disease by inhibiting bacterial bile salt hydrolase activity.

Propolis is commonly used in traditional Chinese medicine. Studies have demonstrated the therapeutic effects of propolis extracts and its major bioactive compound caffeic acid phenethyl ester (CAPE) on obesity and diabetes. Herein, CAPE was found to have pharmacological activity against nonalcoholic fatty liver disease (NAFLD) in diet-induced obese mice. CAPE, previously reported as an inhibitor of bacterial bile salt hydrolase (BSH), inhibited BSH enzymatic activity in the gut microbiota when administered to mice. Upon BSH inhibition by CAPE, levels of tauro-ß-muricholic acid were increased in the intestine and selectively suppressed intestinal farnesoid X receptor (FXR) signaling. This resulted in lowering of the ceramides in the intestine that resulted from increased diet-induced obesity. Elevated intestinal ceramides are transported to the liver where they promoted fat production. Lowering FXR signaling was also accompanied by increased GLP-1 secretion. In support of this pathway, the therapeutic effects of CAPE on NAFLD were absent in intestinal FXR-deficient mice, and supplementation of mice with C16-ceramide significantly exacerbated hepatic steatosis. Treatment of mice with an antibiotic cocktail to deplete BSH-producing bacteria also abrogated the therapeutic activity of CAPE against NAFLD. These findings demonstrate that CAPE ameliorates obesity-related steatosis at least partly through the gut microbiota-bile acid-FXR pathway via inhibiting bacterial BSH activity and suggests that propolis enriched with CAPE might serve as a promising therapeutic agent for the treatment of NAFLD.

Cyclodextrin-NH-MIL-53 open tubular stationary phase for capillary electrochromatography enantioseparation.

A novel chiral group functionalized metal-organic framework, Cyclodextrin-NH-MIL-53, was synthesized and modified on the inner wall of a capillary column via a post-synthetic process. The prepared chiral metal-organic framework was utilized as a chiral capillary stationary phase and used in an open-tubular capillary electrochromatography method to enantioseparate several racemic amino acids. Excellent enantioseparation of five pairs of enantiomers was obtained in this chiral separation system (Resolutions of D/L-Alanine = 16.844, D/L-Cysteine = 3.617, D/L-Histidine = 9.513, D/L-Phenylalanine = 8.133, and D/L-Tryptophan = 2.778). The prepared Cyclodextrin-NH-MIL-53 and the Cyclodextrin-NH-MIL-53-based capillary columns were characterized by scanning electron microscopy, X-ray diffraction, Fourie-transform infrared spectroscopy, and circular dichroism. The chiral capillary electrochromatography conditions, such as separation conditions, amount of Cyclodextrin-NH-MIL-53, and electroosmotic flow, were optimized. This research is estimated to present a novel insight and method for the design and use of metal-organic framework-based capillaries for enantioseparation.

Assessing the export trade risk of bluetongue virus serotypes 4 and 8 in France.

Bluetongue (BT) causes an economic loss of $3 billion every year in the world. After two serious occurrences of BT (bluetongue virus [BTV] occurrence in 2006 and 2015), France has been controlling for decades, but it has not been eradicated. As the largest live cattle export market in the world, France is also one of the major exporters of breeding animals and genetic materials in the world. The biosafety of its exported cattle and products has always been a concern. The scenario tree quantitative model was used to analyze the risk of BTV release from French exported live cattle and bovine semen. The results showed that with the increase in vaccination coverage rates, the risk decreased. If the vaccine coverage is 0%, the areas with the highest average risk probability of BTV-4 and BTV-8 release from exported live cattle were Haute-Savoie and Puy-de-Dôme, and the risk was 2.96 × 10-4 and 4.25 × 10-4 , respectively. When the vaccine coverage was 90%, the risk probability of BTV-4 and BTV-8 release from exported live cattle was 2.96 × 10-5 and 4.24 × 10-5 , respectively. The average probability of BTV-8 release from bovine semen was 1.09 × 10-10 . Sensitivity analysis showed that the probability of false negative polymerase chain reaction (PCR) test and the probability of BT infection in the bull breeding station had an impact on the model. The identification of high-risk areas and the discovery of key control measures provide a reference for decision makers to assess the risk of French exports of live cattle and bovine semen.

Epidemiologic and import risk analysis of Peste des petits ruminants between 2010 and 2018 in India.

BACKGROUND: Peste des petits ruminants (PPR) is a serious disease that affects goats, sheep and other small ruminants. As one of the earliest and most serious countries, PPR has seriously threatened India's animal husbandry economy. RESULTS: In this study, the spatiotemporal characteristics of the PPR in India outbreaks were analyzed. Between 2010 and 2018, the epidemic in India broke out all over the country in a cluster distribution. Epidemic clusters in northern and southern India are at higher risk, and the outbreak time of PPR has significant seasonality. The results of the analysis of the development and transmission of PPR under the natural infection conditions showed that the PPR outbreak in India reached a peak within 15 days. Finally, the quantitative risk analysis results based on scenario tree show showed that the average probability of infecting PPRV in live sheep exported from India was 1.45 × 10-4. CONCLUSIONS: This study analyzed the prevalence of PPR in India. The analysis of transmission dynamics on the development of the epidemic provides a reference for the prevention and control of the epidemic. At the same time, it provides risk analysis and suggestions on trade measures for the trading countries of India.

Risk assessment and early warning of the presence of heavy metal pollution in strawberries.

Heavy metal pollution is a major threat to agricultural produce and it can pose potential ecological risks which subsequently impacts on human health. Strawberries are an economically important produce of China. The intrinsic link of heavy metal pollution risk in the soil-strawberry ecosystem is of concern. In this study, the pollution index of heavy metal pollutants in farmlands of different provinces were evaluated, and the results showed significantly high levels of cadmium. In addition, Nemerow integrated pollution index analysis showed that low-pollution farmlands only accounted for 14.07% of the total arable land area. Then, the transfer factors were used to calculate the migration of heavy metals from the soil into strawberries. The results showed that cadmium and nickel were relatively high in strawberries from the Guangxi province. Similar results were found for mercury in Jiangxi Province. The pollution index of single food pollution also showed that mercury in strawberries from Jiangxi Province was at a moderate pollution level. The comprehensive pollution index indicated that heavy metal pollution in strawberries in Central China may be severe. In addition, spatial clustering analysis showed that cadmium, chromium, lead, arsenic and zinc in strawberries had significant hotspot clustering in central, south and southwest China. Finally, our studies also suggested that the risk of carcinogenic and non-carcinogenic diseases was higher in the (2, 4] years age group than in other age groups. People in Yunnan Province were also found to have a higher non-carcinogenic risk than those in other provinces and cities in China. This study provides a comprehensive view of the potential risks of heavy metal contamination in strawberries, which could provide assistance in the design of regulatory and risk management programs for chemical pollutants in strawberries, thus ensuring the safety of consumption of these edible fruits.

An Improved POD Model for Fast Semi-Quantitative Analysis of Carbendazim in Fruit by Surface Enhanced Raman Spectroscopy.

The current detection method of carbendazim suffers from the disadvantages of complicated preprocessing and long cycle time. In order to solve the problem of rapid quantitative screening of finite contaminants, this article proposed a qualitative method based on characteristic peaks and a semi-quantitative method based on threshold to detect carbendazim in apple, and finally the method is evaluated by a validation system based on binary output. The results showed that the detection limit for carbendazim was 0.5 mg/kg, and the detection probability was 100% when the concentration was no less than 1 mg/kg. The semi-quantitative analysis method had a false positive rate of 0% and 5% at 0.5 mg/kg and 2.5 mg/kg, respectively. The results of method evaluation showed that when the added concentration was greater than 2.5 mg/kg, the qualitative detection method was consistent with the reference method. When the concentration was no less than 5 mg/kg, the semi-quantitative method is consistent between different labs. The semi-quantitative method proposed in this study can achieve the screening of finite contaminants in blind samples and simplify the test validation process through the detection probability model, which can meet the needs of rapid on-site detection and has a good application prospect.

Loureirin B activates GLP-1R and promotes insulin secretion in Ins-1 cells.

Loureirin B (LB) is a natural product derived from Sanguis draconis, which has hypoglycaemic effects. In order to research the possible target of LB in the treatment of diabetes, molecular docking was used to simulate the interaction between LB and potential targets, and among them, glucagon-like peptide-1 receptor (GLP-1R) had the optimal results. Further, spectroscopy and surface plasmon resonance (SPR) experiments were applied to detect the interaction between LB and GLP-1R. Ultimately, after GLP-1R siRNA interfering the expression of GLP-1R in Ins-1 cell, the promoting insulin secretion of LB was weaken, which directly proved that GLP-1R plays an important role. These results show that LB promotes insulin secretion of Ins-1 cells through GLP-1R. Hence, the strategy of LB as a prodrug will provide a potential approach for non-peptide GLP-1R agonist.

Salty Biofluidic Sample Clean-Up and Preconcentration with a Paper-Based Ion Concentration Polarization Interface.

Charged species from complex media could be separated and enriched taking advantage of ion concentration polarization (ICP) effect; thus, ICP can be used for sample purification and improvement of detection sensitivity. In this paper, a novel and reliable ICP interface was established on a paper-based analytical device (PAD) by using ion exchange membrane, and electrokinetic stacking of target analytes from salty media was successfully demonstrated. Steady ICP effect was well observed in aqueous solution with up to 400 mM NaCl as shown by a fluorescent probe, which makes it possible to directly process salty physiological samples such as blood and urine with this type of PAD. Application of this method was demonstrated by direct online stacking of total protein from urine samples and image-based colorimetric detection by a smartphone camera. The linear response was in the range of 50-350 mg/L (R2 = 0.99), with recovery rate in the range of 94.8-107.6% and relative standard deviation below 7.1%. The obtained results were consistent with that of the clinical method. As an off-line sample pretreatment method, the feasibility for rapid tandem mass spectrometry detection of amino acids from serum samples was also investigated, and promising results were obtained. This PAD method is of low cost, easy to operate, and reliable. As a disposable PAD, it is useful not only for sensitive point-of-care testing but also for direct purification and concentration of complex and highly conductive physiological samples for fast and accurate detection with advanced analytical instruments.

Risk assessment and integrated surveillance of foot-and-mouth disease outbreaks in Russia based on Monte Carlo simulation.

BACKGROUND: Foot-and-mouth disease (FMD) is a highly contagious disease of livestock worldwide. Russia is a big agricultural country with a wide geographical area where FMD outbreaks have become an obstacle for the development of the animal and animal products trade. In this study, we aimed to assess the export risk of FMD from Russia. RESULTS: After simulation by Monte Carlo, the results showed that the probability of cattle infected with FMD in the surveillance zone (Surrounding the areas where no epidemic disease has occurred within the prescribed time limit, the construction of buffer areas is called surveillance zone.) of Russia was 1.29 × 10- 6. The probability that at least one FMD positive case was exported from Russia per year in the surveillance zone was 6 %. The predicted number of positive cattle of the 39,530 - 50,576 exported from Russia per year was 0.06. A key node in the impact model was the probability of occurrence of FMD outbreaks in the Russian surveillance zone. By semi-quantitative model calculation, the risk probability of FMD defense system defects was 1.84 × 10- 5, indicating that there was a potential risk in the prevention and control measures of FMD in Russia. The spatial time scan model found that the most likely FMD cluster (P < 0.01) was in the Eastern and Siberian Central regions. CONCLUSIONS: There was a risk of FMDV among cattle exported from Russia, and the infection rate of cattle in the monitored area was the key factor. Understanding the export risk of FMD in Russia and relevant epidemic prevention measures will help policymakers to develop targeted surveillance plans.

Glioma stages prediction based on machine learning algorithm combined with protein-protein interaction networks.

BACKGROUND: Glioma is the most lethal nervous system cancer. Recent studies have made great efforts to study the occurrence and development of glioma, but the molecular mechanisms are still unclear. This study was designed to reveal the molecular mechanisms of glioma based on protein-protein interaction network combined with machine learning methods. Key differentially expressed genes (DEGs) were screened and selected by using the protein-protein interaction (PPI) networks. RESULTS: As a result, 19 genes between grade I and grade II, 21 genes between grade II and grade III, and 20 genes between grade III and grade IV. Then, five machine learning methods were employed to predict the gliomas stages based on the selected key genes. After comparison, Complement Naive Bayes classifier was employed to build the prediction model for grade II-III with accuracy 72.8%. And Random forest was employed to build the prediction model for grade I-II and grade III-VI with accuracy 97.1% and 83.2%, respectively. Finally, the selected genes were analyzed by PPI networks, Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, and the results improve our understanding of the biological functions of select DEGs involved in glioma growth. We expect that the key genes expressed have a guiding significance for the occurrence of gliomas or, at the very least, that they are useful for tumor researchers. CONCLUSION: Machine learning combined with PPI networks, GO and KEGG analyses of selected DEGs improve our understanding of the biological functions involved in glioma growth.

Effect of roasted peanut allergen Ara h 3 protein on the sensitization of Caco-2 cells.

BACKGROUND: Roasted peanut is widely loved as a kind of food with rich taste. However, peanut allergy is one of the major threats to human health, which affects about 5% of children and 1.4-2% of adults in the world. RESULTS: To evaluate the sensitization mechanism of peanut allergen Ara h 3, Caco-2 cells as the model, which has the similar structure and function to differentiated small intestinal epithelial cells. Compared with Ara h 3-raw (purified from raw peanut) group, more significant results such as the inhibited Caco-2 cell viability and proliferation, the increased secretion of reactive oxygen species (ROS) and the decreased transepithelial electrical resistance were obtained in Ara h 3-roasted (purified from roasted peanut) group. Accordingly, oxidative stress and NF-κB signaling pathway were more imbalanced, which lead to the increased of thymic stromal lymphopoietin (TSLP), interleukin 6 (IL-6), IL-8 and monocyte chemotactic protein 1 (MCP-1). Then, the gene expression of tight junction proteins ZO-1, occludin and JAM-1 were reduced, which proved that the integrity of the Caco-2 monolayer barrier is severely damaged. CONCLUSION: These finding identify the mechanisms of the allergenicity of roasted peanut allergy proteins are probably associated with intestinal uptake and cytokine dependent allergies. The aggravated allergic reaction might be caused by the increment of TSLP, IL-6, IL-8 and MCP-1 due to the activated NF-κB signaling pathway, and the enhanced transport of Ara h 3-roasted protein by Caco-2 monolayer. © 2021 Society of Chemical Industry.

The Burden of Mental Illness and Mental Distress on Family Members.

BACKGROUND: The Organisation for Economic Cooperation and Development reports that one in every two people experiences a mental illness in their lifetime, and developed policy guidelines to address the impact of mental health-related issues on employment and health. The results of this policy initiative have been reported in many member countries but no survey findings are available yet for Japan. Previous studies in Japan focused on the social costs of mental illness, but little empirical evidence exists on burdens created by mental illness in individual households. AIMS: This study investigated the effects of mental illness and mental distress on family members' employment and sleep time. Employed men and women family members and unemployed women family members who wanted to work were included in the study. METHODS: Japanese survey data from the 2013 Comprehensive Survey of Living Conditions were analyzed to identify the above-mentioned effects. A propensity score matching method was used to create a valid comparison group for family members of patients with mental illness and distress. RESULTS: For depression, family member average weekly work hours decreased by a range of 1.06 (p%lt;0.01) to 1.18 (p<0.01) for men, and 0.53 (p<0.1) to 1.06 (p<0.05) for women. For dementia (termed "major neurocognitive disorder" in the DSM-5), there were no statistically significant effects on work hours in men, but the work hours of employed women increased, ranging from 1.15 (p<0.05) to 1.25 (p<0.01). Mental illness in a family member also significantly influenced future employment prospects of unemployed women. In family members of patients with dementia, sleep time decreased by a range of 3.6 minutes (p<0.05) to 4.8 minutes (p<0.01) per night for men and 12 minutes (p<0.01) per night for women. DISCUSSION AND LIMITATIONS: These findings can add to the existing evidence on the effects of mental illness and distress on family members' work hours and sleep time in Japan, which are consistent with research from other countries such as Germany, the UK, and the US. This study has two limitations. First, the magnitude of the effect of mental illness is limited with respect to the illness category in our study, since the severity of the condition and the impact on actual daily life may vary across categories or differ even within the same category. Second, measurement error might exist in the self-reported mental illness measures. POLICY IMPLICATIONS: First, cooperation and mutual support between employers and the community are necessary to support working family caregivers by allowing them to adjust work schedules to accommodate caregiving responsibilities. Second, social institutional policies are needed that reduce the burden of informal caregiving for family members with mental illness and increase access to long-term care for those in need. Third, since mental illness and distress have been shown to affect family members' sleep schedules, health care programs must focus on promoting caregivers' general health. IMPLICATIONS FOR FUTURE RESEARCH: To further address the burden of mental illness and distress on family members, future research should examine illness severity as measured by Activities of Daily Living.

Effects of Maillard reaction on structural modification and potential allergenicity of peanut 7S globulin (Ara h 1).

BACKGROUND: Ara h 1 is a major food allergen in peanuts. Recently, many studies have revealed that the Maillard reaction (MR) affects the allergenicity of food proteins. RESULTS: To investigate the influence of the MR on the allergenicity of Ara h 1, R-Ara h 1 was processed with glucose in dry heating conditions for different periods. The extent of the MR was assessed by four methods. The changes in secondary and tertiary structures were characterized through spectroscopy assays. Advanced glycation end products (AGE) structures were identified by protein sample dry heating for 60 min, indicating the formation of AGE-Ara h 1. Simulated gastric fluid (SGF) digestion analysis showed that AGE-Ara h 1 has higher resistance to peptic digestion than R-Ara h 1. The BALB/c mouse model was also utilized to explore the effect of the MR on the allergenicity of Ara h 1, and the results showed that the Th2-type cytokines, antibodies, and histamine content increased, and there was a greater degree of degranulation of rat basophilic leukemia (RBL) cells in the AGE-Ara h 1 group compared with the R-Ara h 1 group. CONCLUSION: During the process of dry heating, proteins participated in the MR with changes in secondary and tertiary structures. The condition applying a temperature of 100 °C for 60 min caused the formation of AGE-Ara h 1. Simulated gastric fluid digestion analysis showed that AGE-Ara h 1 had a greater resistance to peptic digestion than R-Ara h 1. The BALB/c mouse model showed that AGE-Ara h 1 had more allergenicity, indicating that the MR could enhance the allergenicity of Ara h 1. © 2020 Society of Chemical Industry.

GRK5 Regulates Social Behavior Via Suppression of mTORC1 Signaling in Medial Prefrontal Cortex.

Impairments in social behaviors are features of a number of psychiatric diseases associated with subtle alterations in the medial prefrontal cortex (mPFC) circuitry. G protein-coupled receptor kinase (GRK) 5 is widely expressing in the cortex, however, its role in regulation of the mPFC activity and the development of social behaviors and psychiatric disorders is unclear. Here, we found that GRK5 dificiency in mice caused social behavior impairments. Further morphological, electrophysiological, and biochemical analyses showed abnormal postsynaptic ultrastructure, impaired excitatory synaptic transmission, the increased association of raptor with mTOR, and overactivated mTORC1-S6K signaling in the mPFC of Grk5-/- mice. Conditional knockdown of GRK5 in the mPFC caused impairments in social interaction and social novelty recognition behaviors; whereas selectively overexpressing GRK5 in the mPFC of Grk5-/- mice rescued the social novelty recognition phenotype. Inhibition of the overactivated mTORC1-S6K signaling pathway by rapamycin or mGluR5 antagonist ameliorated the deficiency of the excitatory synaptic transmission in the mPFC and the social recognition of Grk5-/- mice. These results indicate that GRK5 is critical for maintaining normal mTORC1 signaling and connectivity in mPFC, and normal social behavior.

Risk analysis of African swine fever in Poland based on spatio-temporal pattern and Latin hypercube sampling, 2014-2017.

BACKGROUND: African swine fever (ASF) is a devastating infectious disease of pigs. ASF poses a potential threat to the world pig industry, due to the lack of vaccines and treatments. In this study, the Geographic Information System (GIS) spatial analysis was applied to analyze the distribution, dispersion of the epidemic and clustering of ASF in Poland. RESULTS: The results show that the center of the epidemic moved gradually towards the southwest, and the distribution of the epidemic changed from south-north to east-west. Through space-time scan statistical analysis, the 3 clusters major of wild boar cases involve longer time spans and larger radii, while the other five with higher relative risks involved in domestic pigs. And then, a quantitative model was constructed to analyse the risk of releasing African swine fever virus (ASFV) from Poland by the legal export of pork and pork products. The Latin hypercube sampling results show that the probability is relatively low (the average value is 4.577 × 10- 7). CONCLUSIONS: All the identification of the spatio-temporal patterns of the epidemic and the risk analysis model would give a further understanding of the dynamics of disease transmission and help to design corresponding measures to minimize the catastrophic consequences of potential ASFV introduction.

Different thermal processing effects on peanut allergenicity.

BACKGROUND: Peanut allergy is one of the most common food allergies worldwide. Studies have shown that the incidence of peanut allergies in Western-born Asians is higher than that in Asia-born Asians. Notably, Europeans and Americans mostly eat roasted peanuts, whereas Asians mostly eat boiled or fried peanuts. RESULTS: BALB/c mice were sensitized using purified protein from raw, roasted or boiled peanuts, then fed the same by oral gavage. The relevant allergic reactions were studied using BALB/c mice model, including a rat basophilic leukemia (RBL) cell model, simulated gastric fluid experiments, and ultraviolet (UV) and circular dichroism (CD) spectral analysis. Serological studies showed increased levels of immunoglobulin E, interleukin-4 and interleukin-5, and pathological studies showed mast cell degranulation and inflammatory changes in jejunal tissues, with an increase in thymic stromal lymphopoietin (TSLP) gene expression in all treatment groups compared with the control group (phosphate-buffered saline). Compared with the raw peanut group, sera from the roasted peanut group produced a significant increase in RBL ß-hexosaminidase A release in vitro, and roasted peanuts showed increased resistance to digestion in simulated gastric fluid experiments. Ultraviolet and CD spectral analyses showed that the roasting and boiling processes altered the structure of the major peanut allergens, which may have contributed to the differences observed in peanut allergenicity. CONCLUSION: Our findings indicate that peanut allergies are related to peanut thermal processing methods. In our mouse model, the raw, roasted and boiled peanuts elicited different degrees of allergic response. Compared with raw peanut, roasted peanuts show a higher allergenicity, whereas the boiled peanuts show a lower allergenicity. © 2018 Society of Chemical Industry.

DNA sequence-based re-assessment of archived Cronobacter sakazakii strains isolated from dairy products imported into China between 2005 and 2006.

BACKGROUND: Cronobacter species are associated with severe foodborne infections in neonates and infants, with particular pathovars associated with specific clinical presentations. However, before 2008 the genus was regarded as a single species named Enterobacter sakazakii which was subdivided into 8 phenotypes. This study re-analyzed, using multi-locus sequence typing (MLST) and whole genome sequence with single nucleotide polymorphism analysis (WGS-SNP), 52 strains which had been identified as Enterobacter sakazakii as according to the convention at the time of isolation. These strains had been isolated from dairy product imports into China from 9 countries between 2005 and 6. Bioinformatic analysis was then used to analyze the relatedness and global dissemination of these strains. RESULT: FusA allele sequencing revealed that 49/52 strains were Cronobacter sakazakii, while the remaining 3 strains were Escherichia coli, Enterobacter cloacae, and Franconibacter helveticus. The C. sakazakii strains comprised of 8 sequence types (STs) which included the neonatal pathovars ST1, ST4 and ST12. The predominant sequence type was ST13 (65.3%, 32/49) which had been isolated from dairy products imported from 6 countries. WGS-SNP analysis of the 32 C. sakazakii ST13 strains revealed 5 clusters and 5 unique strains which did not correlate with the country of product origin. CONCLUSION: The mis-identification of E. coli, E. cloacae and F. helveticus as Cronobacter spp. reinforces the need to apply reliable methods to reduce the incidence of false positive and false negative results which may be of clinical significance. The WGS-SNP analysis demonstrated that indistinguishable Cronobacter strains within a sequence type can be unrelated, and may originate from multiple sources. The use of WGS-SNP analysis to distinguishing of strains within a sequence type has important relevance for tracing the source of outbreaks due to Cronobacter spp.

Loureirin B promotes insulin secretion through inhibition of KATP channel and influx of intracellular calcium.

The development of new diabetes drugs continues to be explored. Loureirin B, a flavonoid, extracted from Dracaena cochinchinensis, has been confirmed to increase insulin secretion and decrease blood glucose levels. For searching the promotion of insulin secretion with the treatment of loureirin B, experiments were employed based on cell experiments and computational methods. First, promotion of insulin secretion was dependent on extracellular glucose concentration. At the genetic level, loureirin B enhanced the relative mRNA level of Pdx-1 and MafA. Meanwhile the intracellular level of ATP increased due to the continuous absorption of glucose. Further experiments showed that the currents of KATP channel on Ins-1 cells were inhibited and the voltage-dependent calcium channels were subsequently activated. The increase of Cx43 protein expression might mediate the Ca2+ to the intracellular. Through computational simulation, we hypothesized that loureirin B might interact with KATP channels to promote insulin secretion. In conclusion, it could be concluded that loureirin B promoted insulin secretion mainly through increasing mRNA level of Pdx-1, MafA, intracellular ATP level, inhibiting the KATP current, influx of Ca2+ to the intracellular.