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Yuling paste, a traditional Chinese health food derived from longan pulp and American ginseng, undergoes a unique processing method involving nine cycles of steaming and sun-drying. Ultra-high-performance liquid chromatography tandem mass spectrometry combined with widely targeted metabolomics has been used to examine the dynamic change in metabolite profiles through the processing. A total of 758 metabolites were identified. Processing significantly affects metabolite changes, and network pharmacology is subsequently used to explore potential pharmacological ingredients. After processing, the contents of active ingredients such as ginsenoside rh2, oleanolic acid, choline, d-glucose, and D-galacturonic acid were found to increase significantly. These increases can be correlated to the enhancement of five distinct pathways, and the contents of naringenin-7-O-glucoside, adenosine, pantothenic acid, and D-sucrose decreased after the processing, correlating with decreases in two different pathways. This study provides a comprehensive reference and scientific basis for understanding the health benefits associated with this traditional health food.

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Lactococcus lactis, a lactic acid bacterium, has been widely used in the fermented dairy products. The acid tolerance of L. lactis is of great importance to food fermentation and probiotic applications. As the first barrier of bacteria, the cell wall has a protective effect on strains under many stress conditions, whereas the regulatory mechanism has rarely been reported. Here, based on the transcription analysis of 9 cell wall or membrane-related genes of L. lactis F44 under acid stress, the transcription levels of DACB, DLTD, YLBA, HRTA, WP_080613266.1 (1610), and ERFK genes were significantly increased. We constructed 9 overexpressing strains with the cell wall or membrane-related genes, respectively. It was demonstrated that the survival rates under acid stress of DACB, DLTD, and ERFK were significantly higher than that of wild-type F44. To investigate the regulatory mechanism, a DNA pull-down assay was used to identify the transcriptional regulators of these 3 genes. It was discovered that the 2-component system (TCS) transcriptional regulator TCSR7 bound to the upstream region of DLTD involved in the teichoic acid (TA) alanylation. The combination was confirmed through an electrophoretic mobility shift assay in vitro. Reverse-transcription quantitative PCR results indicated that TCSR7 upregulated the expression of DLTD gene. In addition, the transcription level of TCSR7 increased approximately 1.8-fold (log2 fold change) under acidic conditions. In summary, this study found that TCSR7 was induced by acid stress to upregulate the transcription level of the DLT operon genes, which might increase the positive charge on the cell membrane surface to increase the acid tolerance of the strain. This study lays the foundation for the regulatory mechanism of TA alanylation under acid stress.

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Ultraviolet (UV) irradiation is widely used for water treatment due to its effectiveness against a wide range of waterborne pathogens with minimal production of regulated disinfection byproducts. However, in this study, the formation of methyl chloride (CH3Cl) from guaiacol and chloride was observed during UV254 irradiation. The results indicated that direct photolysis of guaiacol produced an arenium ion, and the reactive methoxy group was further transformed to CH3Cl in the presence of chloride. O-quinone was detected as the primary product of the degradation of guaiacol resulting from UV254 irradiation. Other organic compounds containing methoxy, ethoxy, or methylamino groups with structures that are similar to guaiacol were also demonstrated to generate halocarbons in aqueous chloride or bromide solution under UV254 irradiation. Scavenging experiments and removal of oxygen demonstrated that neither oxygen nor chlorine radicals were involved in CH3Cl formation. In seawater samples, CH3Cl was also detected in the presence or absence of added organic matter. These results demonstrate that CH3Cl can be formed during UV254 irradiation in saline water and that attention should be paid to this compound and structurally-related compounds in the application of UV254 processes.

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Carbamate insecticides, which are common micropollutants in surface waters, were found to generate dichloromethlyamine (DCMA) during chlorination. DCMA formation from other precursors has been reported previously; it is part of the emerging class of nitrogen-based disinfection byproducts (N-DBPs) of health concern in chlorinated water. However, there is a limited understanding about its formation, stability, and toxicity. Four carbamate insecticides (methomyl, carbofuran, carbaryl, and thiodicarb) were examined as DCMA precursors over a range of reaction conditions, based on variables of chlorine/precursor (Cl/P) molar ratio, pH, time, and temperature. DCMA was found to be the dominant volatile DBP to result from chlorination of all four carbamate insecticides, with molar yields ranging from 12% to 150% at a Cl/P molar ratio of 20. Further experiments indicated CH3NCl2 to be relatively stable, with a half-life of up to 35 h in water. The toxicity of CH3NCl2 was investigated using a bacterial bioluminescence inhibition test and survival of human lung tumor cells. The results of these toxicity assays indicated that CH3NCl2 is about 3 orders of magnitude more toxic than CHCl3. CH3NCl2 concentrations in the ppb range were observed to result from chlorination of surface water or tap water samples collected from several different locations in China. The results suggest that precursors to CH3NCl2 formation are ubiquitous and that CH3NCl2 poses a hazard to public health and the environment and should be considered in disinfection chemistry and water treatment.

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The Anderson model was founded in 1968, based on the three initial components of predisposing characteristics,enabling resources and need as its original components.It has been modified and improved for five times since then by increasing measurement index,adjusting structure,expanding path relation,and transforming a-nalysis path,to become a complete theoretical model and the feasibility of empirical research finally.The Anderson Model was widely recognized by the international academia,and used in the field of healthcare services research in U-nited States and Europe as a theoretical model for analyzing the main influence factors of utilization behavior of health service,such as individual medical choice, medical costs, disease screening, drug use etc.This paper aimed to summarize the development and the usage of the model in foreign countries.It will be not only be helpful to the theo-retical and applied research in the field of healthcare in China, but also be helpful to improving the medical and health policy and designing the questionnaire in the National Health Service Survey.

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Chloride can accumulate in chlorinated swimming pool water. Although substantial efforts have been made to examine the effects of halide ions on the formation of volatile disinfection byproducts (DBPs), most have focused on bromide. The effects of chloride ion concentration on the formation of volatile DBPs in swimming pools remain largely unstudied. In this study, chlorination of typical precursors and body fluid analogue (BFA) were investigated with variable chloride concentration and pH. The formation of three volatile DBPs (NCl3, CHCl3 and CNCHCl2) was observed to be linearly correlated with chloride concentration, both in bench experiments and in actual swimming pool water samples. Free chlorine consumption was also observed to increase with chloride concentration. These behaviors appear to be attributable to shifts in speciation of free chlorine, with higher chloride resulting in higher concentration of molecular chlorine (Cl2), which is much more reactive than HOCl. The results of this work suggest that changes in pool management strategies to promote low chloride concentration could be important for control of volatile DBPs in pools and to economize free chlorine usage.

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Highly fluorescent bilayer nanocoils assembled from an asymmetric perylene diimide molecule exhibit unprecedented sensitivity to trace amines, that is, three orders of magnitude greater than our previously reported solid nanofibers. The coiled nanostructure design for new sensing materials offers a novel option for optimizing the sensitivities of fluorescence sensors based on organic nanomaterials.

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Cyanogen chloride (CNCl) and trichloramine (NCl3) are important disinfection byproducts in chlorinated swimming pools. However, some unknowns exist regarding the precursors of their formation. In this study, uric acid is shown to be an efficient precursor to formation of CNCl and NCl3. The molar yields of CNCl and NCl3 were observed to be as high as 44% (pH = 6.0, chlorine/precursor molar ratio [Cl/P] = 6.4) and 108% (pH = 7.0, Cl/P = 30), respectively, both being strong functions of Cl/P, pH, and temperature. Analysis of swimming pool water samples, combined with the results of experiments involving chlorination of uric acid, and chlorination of body fluid analog mixtures, indicated that uric acid chlorination may account for a large fraction of CNCl formation in swimming pools. Moreover, given that uric acid introduction to pools is attributable to urination, a voluntary action for most swimmers, these findings indicate important benefits to pool water and air chemistry that could result from improved hygiene habits on the part of swimmers.

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<p><b>OBJECTIVE</b>To explore the role of sTRAIL in the pathogenesis of HBV infection in human being.</p><p><b>METHODS</b>sTRAIL in 153 patients' sera was examined with ELISA. Correlations between sTRAIL and liver functional parameters were analysed.</p><p><b>RESULTS</b>The levels of sTRAIL in patients with various clinical types of hepatitis B as well as primary hepatocellular carcinoma were all higher than that in normal persons and became almost normal in recovering stage cases. In acute and chronic HBV infection, sTRAIL level was negatively correlated with ALT, AST and total bilirubin levels, and positively correlated with serum albumin.</p><p><b>CONCLUSION</b>The results indicated that higher level of sTRAIL expression is correlated with liver damage, and apoptosis induced by sTRAIL is one of the mechanisms of liver damage in HBV infection.</p>

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