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The viable but nonculturable (VBNC) state refers to a state in which bacteria lose their ability to grow and reproduce in conventional media under adverse environmental stress conditions. Bacteria in the VBNC state are usually still metabolically active and remain pathogenic and virulent. Bacteria in the VBNC state can recover and return to a state where they can be cultured normally under certain suitable conditions, posing potential risks to food safety. In this review, the morphological, physiological, biochemical and biomacromolecular characteristics of bacteria, especially foodborne pathogens, in the VBNC state are comprehensively described. Meanwhile, various factors that induce bacteria to enter the VBNC state, including temperature and pH unsuitable for bacteria survival, are summarized. The laboratory conditions for bacterial recovery from the VBNC state are outlined with special reference to adequate nutrition as an indispensable factor for recovery from the VBNC state. Finally, the major methods for the detection of bacteria in the VBNC state are discussed, including molecular biological methods, flow cytometry, and optical microscopy. Molecular biological methods have been widely used in the detection of bacteria in the VBNC state due to their advantages of accuracy, rapidity and high sensitivity. This review provides more ideas for further research on the induction, resuscitation and detection of foodborne pathogens in the VBNC state.

OBJECTIVES: To explore the temporal expression pattern of LaminB1 in the cochlea of postnatal rat, and whether LaminB1 is associated with cochlear development. MATERIALS AND METHODS: Sprague-Dawley rats ranging from postnatal day 0 (p0) to 21 (p21) were used. The tissues of stria vascularis (STV) including spiral ligament, spiral ganglion cell (SGC), and basilar membrane (BM), including the organ of Corti, were dissected, respectively. Immunofluorescence, quantitative real-time polymerase chain reaction, and western blot were applied to detect the expression of LaminB1 in individual cochlear tissues at both mRNA and protein levels. RESULTS: Immunofluorescence revealed that LaminB1 was localized in the outer hair cells, inner hair cells, Kolliker's organ, Reissner's membrane, SGC, STV, and spiral ligament. The intensity of staining surrounding the scala media decreased during cochlear development. The expression of LaminB1 mRNA and protein in STV, SGC, and BM was at a maximum level at p0 but gradually declined to a minimum level at p21. CONCLUSION: Our research provided direct evidence that LaminB1 was expressed in the developing cochlea and developmentally regulated in cochlear tissues, suggesting a possible role of LaminB1 in cochlear development. Our result provided a theoretical basis for further study about the physiological function of LaminB1 in the peripheral auditory system. [ABSTRACT FROM AUTHOR]

Benzalkonium chloride is a quaternary ammonium compound with bactericidal activity, which is widely used in domestic and healthcare settings as well as in food processing environments. It plays an important role in the prevention and control of foodborne pathogens. However, the presence of biofilms or improper use of benzalkonium chloride may enable foodborne pathogens to adapt to bactericides, affecting the tolerance to homologous or heterologous biocidal agents. The review summarizes the relationship between the adaptation of foodborne pathogens to benzalkonium chloride and their tolerance to this biocide. The reasons for the increased tolerance to benzalkonium chloride are explained from the perspectives of the expression of efflux pump genes, cell membrane modification, and the formation of the viable but non-cultivable (VBNC) state. Furthermore, the influence of benzalkonium chloride adaptation on the antibiotic resistance of foodborne pathogens is discussed, and the reasons for the increased antibiotic resistance are summarized from the perspectives of biofilm formation, spontaneous mutations, horizontal gene transfer, and the role of efflux pumps in antibiotic resistance. This review could help understand the mechanism of the adaption of foodborne pathogens to benzalkonium chloride and provide a reference for the rational use of biocides and the prevention and control of foodborne pathogens.

A series of novel derivatives of isaindigotone, which comes from the root of isaits indinatca Fort, were synthesised (Compound 1-26). Four human gastrointestinal cancer cells (HCT116, PANC-1, SMMC-7721, and AGS) were employed to evaluate the anti-proliferative activity. Among them, Compound 6 displayed the most effective inhibitory activity on AGS cells with an IC50 (50% inhibitory concentration) value of 2.2 µM. The potential mechanism study suggested that Compound 6 induced apoptosis in AGS cells. The collapse of mitochondrial membrane potential (MMP) in AGS cells was proved. In docking analysis, good affinity interaction between Compound 6 and AKT1 was discovered. Treatment of AGS cells with Compound 6 also resulted in significant suppression of PI3K/AKT/mTOR signal pathway. The collapse of MMP and suppression of PI3K/AKT/mTOR signal pathway may be responsible for induction of apoptosis. This derivative Compound 6 could be useful as an underlying anti-tumour agent for treatment of gastric cancer. [ABSTRACT FROM AUTHOR]