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As the dominant spoilage bacterium in meat, Pseudomonas poses a significant threat to meat quality and safety. The biofilm of Pseudomonas not only enhances stress resistance but also provides bio-protection, thereby making the decontamination of Pseudomonas more challenging. In recent years, many studies have been conducted on the mechanism of Pseudomonas biofilm formation, with particular emphasis on the regulatory effect of quorum sensing (QS) and cyclic di-guanosine monophosphate (c-di-GMP) on the mechanism of Pseudomonas biofilm formation. There may be a complex interaction between QS and c-di-GMP. In addition, compared with traditional biofilm inhibition strategies, the development of new inhibition strategies based on the QS system, c-di-GMP and their relationship, which can be more targeted, has more practical significance. Therefore, this article describes the synthesis process of the QS system and c-di-GMP signal molecules and reviews the mechanism of Pseudomonas biofilm formation from the perspectives of the QS system, c-di-GMP and their relationship. Besides, it summarizes the inhibition strategies targeting the QS system and c-di-GMP. This review aims to provide a theoretical foundation for effectively controlling Pseudomonas biofilm in the food industry.

To inhibit the development of adaptive acid tolerance response (ATR) and concurrent multiple stress resistance in Salmonella induced by the residual acid environment from carcass decontamination by organic acid spraying, the inhibitory effect of the addition of oregano essential oil and calcium chloride at different subinhibitory concentrations during acid adaptation on the ATR of Salmonella was investigated by determining the survival ability of Salmonella in acidic, thermal, hyperosmotic and oxidative environments before and after adaptation, and the possible mechanism was explored by determining the relative expression of stress resistance genes before and after treatments. The results indicated that the residual acid (pH 5.4) generated during carcass processing might induce ATR and heat-resistant cross-protection in Salmonella, suggesting a potential food safety risk. After 2 h treatment with hydrochloric acid at pH 3, the loss of the adapted strain in the 1/2 MIC oregano essential oil and 10 mmol/L CaCl2 treatment group increased by 1.32 (lg(CFU/mL)) compared with the control group, and oregano essential oil combined with CaCl2 had a synergistic inhibitory effect on ATR. The addition of oregano essential oil and calcium chloride during acid adaptation down-regulated the expression of the phoP and rpoS genes, which in turn intervened in the two-component system and global transcription factors, thereby suppressing ATR development. Sub-inhibitory concentrations of oregano essential oil inhibited the formation of the acid and heat resistance of acid-adapted Salmonella, but increased the resistance to hyperosmosis, whereas CaCl2 at a concentration of 10 mmol/L combined with sub-inhibitory concentrations of oregano essential oil reduced the osmotic resistance. The results of the current study help to understand the effects of essential oil and CaCl2 on the acid adaptation process of Salmonella and provide a theoretical basis for risk control for the use of organic acids in the beef industry.

Abstracts: In this study, the changes in autophagy and its relationship with beef quality during 14 days of postmortem aging were investigated. In terms of meat color, the L* value increased with aging time, and the a* and b* values increased first and then decreased; the tenderness increased, while the shear force and the expression of desmin decreased (P < 0.05). The water-holding capacity decreased during postmortem aging, while the purge loss and cooking loss increased (P < 0.05). Further studies on autophagy-related proteins showed that the expression of Beclin-1 and microtubule associated protein 1 light chain 3 (LC3), as the markers of autophagy, increased first and then decreased, reaching the maximum at 12 h. AMP-activated protein kinase (AMPK)-mammalian target of rapamycin (mTOR)-yeast Atg1 homolog unc-51 like kinase 1 (ULK1), as an important energy metabolic pathway, activated autophagy in an ischemia and hypoxia environment. During postmortem aging, the protein expressions of AMPK, p-AMPKThr172, and ULK1 all initially increased and subsequently decreased, reaching the maximum at 12 h. The expression of mTOR continuously decreased (P < 0.05), suggesting that autophagy was up-regulated from 0 to 12 h postmortem aging. Pearson correlation analysis showed that the expression levels of autophagy-related proteins were negatively correlated with meat color, but positively correlated with water-holding capacity and shear force during postmortem aging process (P < 0.05). In summary, autophagy could be activated through the AMPK-mTOR-ULK1 signaling pathway during the 336 h postmortem aging process, thereby regulating beef quality.

This study investigated the effect of resveratrol on muscle fiber type transformation in bovine myotubes. Cell viability and related metabolic enzyme activities were measured by methyl thiazolyl tetrazolium (MTT) and colorimetric assays, and myogenic regulatory factors (MRFs), myosin heavy chains (MyHCs), and gene and protein expression related to mitochondrial biogenesis were determined. The results showed that resveratrol treatment significantly increased the gene expression of Myf5, Myf6, MyoG, and MyoD (P < 0.05) and promoted the differentiation of bovine myotubes. Resveratrol significantly increased slow MyHC expression and decreased fast MyHC expression, while upregulating the mRNA expression levels of MyHC I and MyHC IIa and downregulating the mRNA expression levels of MyHC IIx and MyHC IIb (P < 0.05). Resveratrol also significantly increased succinate dehydrogenase (SDH) and malate dehydrogenase (MDH) activity and decreased lactic dehydrogenase (LDH) activity (P < 0.05). In addition, resveratrol increased the gene and protein expression levels of silent information regulator 1 (SIRT1), peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α), nucleus respiratory factors-1 (NRF-1), mitochondrial transcription factor A (TFAM) (P < 0.05). Addition of the SIRT1 inhibitor 6-chloro-2,3,4,9-tetrahydro-1H-carbazole-1-carboxamide (EX527) significantly attenuated resveratrol-induced muscle fiber type transformation (P < 0.05), and the promoting effect of resveratrol on the gene and protein expression of SIRT1, PGC-1α, NRF-1, and TFAM (P < 0.05). Taken together, resveratrol can promote mitochondrial biogenesis and consequently muscle fiber type transformation by activating the SIRT1/PGC-1α signaling pathway.

ObjectiveTo understand the epidemic characteristics of Listeria monocytogenes （L. monocytogenes） from livestock and poultry in China， the contamination and prevalence of L. monocytogenes in livestock and poultry food in China was systematically reviewed via a meta-analysis. The findings can provide data that can help in the prevention and control of L. monocytogenes during the production of livestock and poultry meat.MethodsThe relevant literature on the detection rate of L. monocytogenes in livestock and poultry food published from 2001 to 2022 in China was searched by inputting key search terms on PubMed， Web of Science， Wanfang Database， CNKI， and other data platforms. The meta-analysis was performed using Stata software.ResultsA total of 277 Chinese and English research articles were selected， representing a total of 110 066 samples and a combined L. monocytogenes detection rate of 7.2% （95%CI： 6.4%-8.0%）. The subgroup analysis of different regions showed that the detection rates of this pathogen in Jilin and Heilongjiang were higher than that of other regions. The subgroup analysis of different time periods found that the detection rate of L. monocytogenes decreased with the extension of time. The detection rate of L. monocytogenes in cooked meat （2.9%， 95%CI： 2.4%-3.5%） was much lower than that in raw meat （10.7%， 95%CI： 9.5%-12.0%）， and the detection rate in poultry meat and pork was 11.0% （95%CI： 8.3%-14.0%） and 10.9% （95%CI： 7.9%-14.2%）， respectively， which was slightly higher than that in other types of raw meat.ConclusionThe detection rate of L. monocytogenes in livestock and poultry food is still at a relatively high level in China.

Some serotypes of Escherichia coli (E. coli) such as E. coli O157:H7 can cause serious diseases in humans. Pathogenic E. coli is widespread in primary agricultural products and encounter various environmental stresses during food processing. After a period of adaptation to a weakly acidic environment, it develops an inducible acid tolerance response, which enhances its ability to survive in a strongly acidic environment and may also enhance its resistance to heat, cold, osmotic pressure and antibiotics, posing a great threat to food safety. This article provides an overview of recent progress in research on the inducible acid tolerance response, two-component regulatory system, pH homeostatic system, cell membrane fluidity regulation, macromolecular protection and cross-protection of E. coli, which may provide theoretical guidance for deep understanding of the stress response of E. coli during food processing and for the development of measures for its prevention and control in the future.

With the increasing consumer demand for chilled meat, food safety issues related to chilled meat such as the prevalence and change of pathogenic bacteria during the processing, storage and consumption of chilled meat and their effects on public health have aroused great public concern. Quantitative microbial risk assessment (QMRA) is the core of chill meat safety risk analysis, which provides a theoretical basis for hazard analysis, determination of the critical control points and formulation of food safety goals and regulations. Since the promulgation of the Food Safety Law and the establishment of the Food Safety Risk Assessment Center in China, significant progress has been made in quantitative microbial risk assessment. In this paper, recent research on the quantitative risk assessment of common food-borne pathogens in livestock and poultry meat products is summarized, and recent progress in the application of process risk model, modular process risk model and omics technology in QMRA is reviewed. The current status of the application of quantitative microbial risk assessment in food safety management is summarized to provide reference for the development and application of quantitative microbial risk assessment in chilled meat.

Summary: This study investigated the effect of non‐selenium glutathione peroxidase (NSGPx) activity of Peroxiredoxin 6 (Prdx6) on beef tenderness. Longissimus thoracis et lumborum (LTL) muscle from six cattle were obtained at 30 min post‐mortem. Samples from each muscle were randomly assigned to each of four treatment groups: being incubated in H2O2 (simulation of oxidative stress), mercaptosuccinic acid (MA; inhibiting NSGPx activity), N‐acetyl‐L‐cysteine (NAC; inhibiting oxidative stress and increasing NSGPx activity), and saline (control), respectively. Results indicated that cells increased the expression of Prdx6 and NSGPx activity to resist oxidative stress. The inhibition of NSGPx activity group (MA) significantly decreased the Warner‐Bratzler shear force and increased the degradation of desmin. Moreover, both the H2O2 and the MA treatment significantly increased the Ca2+ concentration in the sarcoplasm, cell apoptotic rate, and caspase 9 and 3 activity. These results demonstrated that inhibiting NSGPx activity of Prdx6 could accelerate beef tenderization by promoting mitochondrial apoptosis. [ABSTRACT FROM AUTHOR]

Exercise addiction (EA) is a pathological behavior exhibited by individuals obsessed with exercise. Il seriously affects the daily lives of addicted individuals and endangers their physical and mental health. Purpose: To investigate the prevalence of exercise addiction and the psychological contributors to its formation in high-level college soccer players. METHODS: Data were obtained from questionnaires completed by high-level college soccer players in China. Ordinary least squares (OLS) regression analysis and conditional process analysis were used to explore the psychological factors and mechanisms underlying the formation of exercise addiction in high-level college soccer players. Results: 1. The prevalence of exercise addiction among college high-level soccer players was 31.3%; 2. Exercise identity, exercise beliefs, and sports participation motivation significantly positively affected exercise addiction (p<.01); 3. Exercise beliefs and sports participation motivation was a substantial mediating factor (p<.01) on exercise identity effects on exercise addiction. Gender showed a significant moderating effect on the influence of exercise identity on exercise beliefs (p<.05). CONCLUSIONS: 1. High-level college soccer players are a high-risk group for exercise addiction; 2. Exercise identity, exercise beliefs, and sports participation motivation are predictors of exercise addiction in high-level college soccer players; 3. The exercise identity of high-level college soccer players has both a direct effect on exercise addiction and an indirect effect on exercise addiction by influencing two mediating variables: exercise beliefs and sports motivation participation. Gender moderates the extent to which exercise identity influences exercise beliefs. [ABSTRACT FROM AUTHOR]

ABSTRACT: Background: Thyroid hormones are indispensable for organ development and maintaining homeostasis. Thyroid diseases, including thyroiditis and thyroid cancer, affect the normal secretion of hormones and result in thyroid dysfunction. Objective: This review focuses on therapeutic applications of stem cells for thyroid diseases. Methods: A literature search of Medline and PubMed was conducted (January 2000–July 2021) to identify recent reports on stem cell therapy for thyroid diseases. Results: Stem cells are partially developed cell types. They have the capacity to form specialized cells. Besides embryonic stem cells and mesenchymal stem cells, organ resident stem cells and cancer stem cells are recently reported to have important roles in forming organ specific cells and cancers. Stem cells, especially mesenchymal stem cells, have anti-inflammatory and anticancer functions as well. Conclusions: This review outlines the therapeutic potency of embryonic stem cells, mesenchymal stem cells, thyroid resident stem cells, and thyroid cancer stem cells in thyroid cells’ regeneration, thyroid function modulation, thyroiditis suppression, and antithyroid cancers. Stem cells represent a promising form of treatment for thyroid disorders.

Background: Involvement of the recurrent laryngeal nerve (RLN) in papillary thyroid carcinoma (PTC) is an important prognostic factor and is associated with a higher risk of recurrence. This study aimed to retrospectively analyze the outcomes of patients treated with hemithyroidectomy (HT) in PTC patients with an exclusive RLN invasion who could not tolerate staged surgery, did not wish to undergo another operation, or had other reasons. Methods: A retrospective review was conducted on 163 patients with PTC and exclusive RLN involvement at our institution between 2013 and 2019. Patients were divided into a total thyroidectomy (TT) group and HT group. The clinicopathologic factors and prognostic outcomes were compared between the two groups. A propensity score-matched analysis was carried out to reduce selection bias, with the following covariates: gender, age, tumor size, multifocality, central lymph node metastasis (CLNM), and RLN resection. The Kaplan–Meier method was used for a comparison of recurrence outcomes. Results: In the baseline data of the 163 PTC patients, tumor size (p < 0.001), multifocality (p = 0.011), CLNM (p < 0.001), and RLN resection (p < 0.008) in the TT and HT groups differed significantly, whereas age and gender did not differ between the two groups. The TT group reported significantly higher temporary and permanent hypoparathyroidism than the HT group (p < 0.001 and p = 0.042, respectively). With 72-month median follow-up, 11 (6.7%) patients developed recurrence. After propensity score matching, 24 patients with HT and 43 patients with TT were included. Recurrence-free survival (RFS) in the matched samples showed no difference between the TT and HT groups (p = 0.092). Conclusion: Our results indicate that HT may be a feasible treatment for PTC patients with exclusive RLN involvement in specific circumstances without significantly increasing the risk of recurrence. Performing a thorough preoperative examination is crucial to exclude multifocal tumors and lymph node metastasis before undergoing HT. [ABSTRACT FROM AUTHOR]

Chilled beef is inevitably contaminated with microorganisms, starting from the very beginning of the slaughter line. A lot of studies have aimed to improve meat safety and extend the shelf life of chilled beef, of which some have focused on improving the decontamination effects using traditional decontamination interventions, and others have investigated newer technologies and methods, that offer greater energy efficiency, lower environmental impacts, and better assurances for the decontamination of beef carcasses and cuts. To inform industry, there is an urgent need to review these interventions, analyze the merits and demerits of each technology, and provide insight into 'best practice' to preserve microbial safety and beef quality. In this review, the strategies and procedures used to inhibit the growth of microorganisms on beef, from slaughter to storage, have been critiqued. Critical aspects, where there is a lack of data, have been highlighted to help guide future research. It is also acknowledge that different intervention programs for microbiological safety have different applications, dependent on the initial microbial load, the type of infrastructures, and different stages of beef processing. [ABSTRACT FROM AUTHOR]