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Objective To establish a non-invasive single nucleotide polymorphism genotyping technology based on direct TaqMan-PCR for high-throughput genotyping of site rs688 and rs964184 associated with lipid metabolism to meet the need for early screening of at-risk populations. Methods Extracted DNA was used to optimize the PCR annealing extension temperature and amplification procedure for the designed TaqMan probe; the oral swabs were placed into the sample treatment solution and then briefly centrifuged, and a small amount of the supernatant was taken for the direct qPCR amplification analysis; the freeze-thawing stability of probe and the effects of sample storage time on genotyping results were explored. Results The technology requires only simple treatment of oral swab for PCR analysis and can be stored at room temperature for 4 d. The optimized method was able to distinguish homozygous wild type, homozygous mutant type and heterozygote at rs688 and rs964184 loci. Conclusions A fast, convenient, high-throughput, and low-cost SNP genotyping method has been established, providing an efficient and accurate new approach for large-scale screening of high-risk populations carrying susceptibility genes.

Fecal microbial contamination in the food chain is a significant concern in the field of food safety as it is one of the most important pathways causing foodborne diseases. Microbial source tracking (MST) is an effective approach to address this issue, which can track the sources and contamination of fecal microbes. MST methods can be categorized into two types: library-dependent methods (LDMs) and library-independent methods (LIMs), with LIMs including culture-dependent and culture-independent methods. The non-culture-dependent method using 16S rRNA and host-microbial interaction genes as specific molecular markers has been widely used to investigate microbial contamination in the food chain. This review provides an overview of the basic principle and characteristics of MST, and focuses on recent advances in MST methods based on host-specific molecular markers for tracing microbial contamination in the food chain. Furthermore, future prospects of MST are discussed based on its unique advantages and disadvantages.

Abamectin is an insecticide, miticide and nematicide that has been extensively used in agriculture for many years. The excessive use of abamectin inevitably pollutes water and soil and might even cause adverse effects on aquatic biota. However, it is currently unclear how abamectin exposure causes neurotoxicity in aquatic organisms. Herein, the early neural system development was assessed in zebrafish embryos following abamectin exposure. After treatment with a concentration gradient of abamectin (0.055, 0.0825, 0.11 mg/L), the survival rate, average heart rate, pericardial edema area and yolk sac edema were all documented in zebrafish embryos (96 hpf). It was found that after abamectin exposure, embryonic brain development was impaired, and motor behaviors were also affected. The fluorescence intensity was reduced in the transgenic embryos (Eno2: GFP). The activities of acetylcholinesterase (AChE) and ATPase were decreased, and the expression of neurodevelopment-related genes, such as sox10, gap43, grin1b, abat, gad1b, grin2b, nestin and glsa, were all inhibited in zebrafish embryo treatment with abamectin. Furthermore, the reactive oxygen species (ROS) were triggered upon exposure to abamectin in zebrafish embryos along with the accumulation of ROS, eventually resulting in neuroapoptosis in the developing embryonic brain. In conclusion, neurodevelopmental toxicity was caused by oxidative stress-induced apoptosis in zebrafish embryos following abamectin exposure. [ABSTRACT FROM AUTHOR]

Bacterial spores are metabolically inactive and highly resistant to harsh environmental conditions in nature and during decontamination processes in food and related industries. However, inducing germination using specific germinants in dormant spores can convert them into vegetative cells which are metabolically active and fragile. The potential utility of a "germinate to eradicate" strategy, also known as germination-inactivation, has been validated in foods. Meanwhile, the strategy has sparked much interest in triggering and maximizing spore germination. Although many details of the spore germination process have been identified over the past decades, there remain many uncertainties, including some signal transduction mechanisms involved in germination. In addition, the successful implementation of the germination-inactivation strategy relies on the sensitive detection of germinative biomarkers within minutes of germination initiation and the optimal timing for the subsequent inactivation step. Meanwhile, the emergence of biomarkers has renewed attention to the practical application of the spore germination process. Here, this review presents the current knowledge of the germination mechanisms of Bacillus spore, influencing factors, and germination biomarkers. It also covers a detailed discussion on the development of germination-inactivation as a spore eradication strategy. [ABSTRACT FROM AUTHOR]

Societal Impact Statement Summary Climate warming and demand for fuller‐bodied wines has resulted in increased grape sugar contents and, therefore, increased alcohol in wines. Concurrently, there are increased warnings about the health risks of alcohol, and consumers seek low‐alcohol options as part of a healthy lifestyle. High alcohol levels can also impact the flavor balance of wines, resulting in economic losses. However, exploration of native vineyard yeasts shows that fermentation with novel species can result in both alcohol reduction and improved wine flavor. Our findings show that native yeasts have the potential to bring the North American cool‐climate wine industry into a healthier future. There is recent interest in developing wines fermented with non‐traditional yeasts that reflect the microbial terroir of the grape‐growing region. These native yeasts inhabit grape skins and can produce wines with distinctive flavor profiles, and when used in concert with traditional wine yeast, the risk of incomplete fermentation is minimized. Non‐traditional yeasts can also produce wines with relatively low alcohol content, an attractive characteristic given the health and societal issues associated with overconsumption. Yeasts isolated from L'Acadie and Pinot Noir grapes grown at Nova Scotia vineyards were identified by DNA sequencing and characterized regarding fermentative properties. Promising isolates of Saccharomyces uvarum, Hanseniaspora uvarum, Wickerhamomyces anomalus, and Zygotorulaspora florentina were selected for mixed and sequential fermentations with Saccharomyces cerevisiae based on their ethanol and SO2 tolerance, β‐glucosidase activity, and low H2S production. The resulting wines were evaluated for sensory properties by 15 experienced panelists. Alcohol levels of many of the fermentations that included non‐traditional yeasts were significantly lower than those made with traditional yeast alone, while fructose was higher, and total phenolic contents were similar. Experienced panelists also found that these fermentations resulted in wines with novel fruit and floral attributes. Our results demonstrate that native yeasts from cool‐climate wine regions can be used in concert with traditional wine yeast to produce novel, lower alcohol wines with a low risk of fermentation failure. This unlocks the potential of naturally occurring yeasts from these vineyards to create wines with flavor profiles that reflect the local wine‐making regions. [ABSTRACT FROM AUTHOR]

Canada is a leading producer of wild lowbush blueberries, most of which are mechanically harvested, washed, individually quick frozen (IQF), and bulk packaged. Still, some berries are harvested by more gentle methods and sold as fresh-packed products. These berries do not undergo a wash step, nor are subjected to antimicrobial treatments. The purpose of this study was to conduct a microbiological survey of berries harvested in the province of Nova Scotia to assess their potential for harborage of bacterial foodborne pathogens. A combination of standardized plate count methods and 3M-Petrifilm protocols were used to enumerate total aerobic mesophilic bacteria (APC), yeasts and molds (YMC), coliforms, and generic E. coli, the latter being an indicator of fecal contamination. Overall, APC and YMC levels were 1.2 and 0.5 log greater, respectively, for berries collected early in the harvest season versus those acquired late season and varied significantly (p < 0.05) between farm (location) and harvest practices used. Berries harvested by our team using sanitized hand rakes (SH) had consistently lower APC and YMC levels than those harvested by farm crews. Yet, when gentle harvesting (GH) methods (hand-raking, walk-behind or modified mechanical harvesters) were employed on farms, lower numbers were generally observed compared to berries harvested by traditional tractor-mounted mechanized harvesters (MH). The presence of coliforms (and their levels) was also impacted by the harvest method, with detection rates of ~29%, 73%, and 92% in SH, GH, and MH samples, respectively. Mean counts were < 2.5 log10 CFU/g for both SH and GH berries, but significantly higher (p < 0.05) on MH berries (3.6 log10 CFU/g). Although ~56% of all berry samples collected (n = 350) contained coliforms, only 12 were positive for E. coli, 9 of which were MH samples. Only the latter had numbers > 2 log10 CFU/g, but none tested positive for Shiga toxin-producing serotype O157 (STEC O157) or Salmonella spp. when using internationally recognized selective enrichment and plating methods. ATP luminescence was used to assess the general hygiene of processing lines, whereby "hot spots" for microbial activity were identified, even after cleaning., Standard selective enrichment and plating methods were used for the detection of Listeria monocytogenes on 61 swab samples taken from berry totes or conveyor belts at different times during processing; 4 swabs tested positive for L. monocytogenes. However, the pathogen could not be detected by direct plating on selective agar without prior enrichment; this indicated its numbers were low. The results from this work demonstrated that alternative gentle harvest methods can reduce microbial numbers on wild blueberries. Although the frequency of fecal contamination in berry samples appeared to be low and targeted human pathogens were not detected; this represents a single study conducted over one harvest season. Therefore, it would be prudent for processors to seek effective antimicrobial technologies prior to packaging, while consumers should use caution and thoroughly wash produce before consumption. Where sporadic detection of L. monocytogenes was observed on environmental samples from the processing line, processors must ensure that effective sanitation programs are implemented to avoid potential food safety risks. [ABSTRACT FROM AUTHOR]

Chameleon chaotic systems have a special property to display various types of chaotic attractors by tuning system parameters, thereby allowing for the generation of diverse chaotic signals that are suitable for various applications. In this paper, we propose and study a class of three-dimensional quadratic chameleon systems capable of transitioning between self-excited and hidden chaotic regimes. Through systematic analysis of the systems, we can identify hidden chaotic attractors in parameter regions where no equilibria exist, or where there is a line equilibrium, or where a single stable equilibrium exists. In order to study the basic properties of the system, we carried out both local stability analysis and Hopf bifurcation analysis. Further bifurcation analysis and Lyapunov exponent calculation uncovered intricate transitions among periodic, chaotic, and hidden chaotic regimes as the system parameters varied. Through the research, we find that antimonotonicity holds significant implications for creating various types of chaotic dynamics in the chameleon systems. Furthermore, we find that by adjusting the values of parameters, the system can display a self-excited chaotic attractor, a hidden chaotic attractor with no equilibrium, a hidden chaotic attractor with a line equilibrium, or a hidden chaotic attractor with a single stable hyperbolic/nonhyperbolic equilibrium point. We are interested in a hidden chaotic system with a stable nonhyperbolic equilibrium point, for which the practical feasibility is verified through circuit simulations. The chameleon chaotic systems studied in this paper expand our understanding of the chaotic mechanisms with various equilibrium configurations. [ABSTRACT FROM AUTHOR]

Objective To analyze the correlation between ≥grade 2 radiation pneumonitis (RP) and dose volume parameters of elderly patients with esophageal cancer after three-dimensional conformal radiotherapy. Methods We collected the data of 250 elderly patients with esophageal cancer who received three-dimensional conformal radiotherapy from different medical centers. The clinical features of patients were analyzed by Chi-square test while dose volume parameters were analyzed by Logistic univariate and multivariate analyses. ROC curve was used to determine the best cut-off value. Results After three-dimensional conformal radiotherapy, 20% of patients developed ≥grade 2 RP. Univariate analysis showed that bilateral pulmonary V5, V10, V20, V30 and mean lung dose were associated with ≥grade 2 RP but multivariate analysis revealed that only V5 and V20 were independent relevant factors of RP. ROC curve indicated that the best cut-off value was V5 < 52.9% and V20 < 23.2%. Conclusion Bilateral pulmonary V5 and V20 are independently related to ≥grade 2 RP in elderly patients with esophageal cancer after 3-D conformal radiotherapy.