In vitro and in vivo activities of scutellarein, a novel polyphosphate kinase 1 inhibitor against Acinetobacter baumannii infection.

BACKGROUND: Inorganic polyphosphate (polyP)-targeted polyphosphate kinase 1 (PPK1) has attracted much attention by virtue of its importance in bacterial pathogenicity and persistence, as well as its exclusive presence in microorganisms. However, only very few drugs have been found to be efficacious in inhibiting the Acinetobacter baumannii (A. baumannii) PPK1 protein. RESULTS: In this study, we identified Scutellarein (Scu), a potent PPK1 inhibitor that could significantly influence PPK1-regulated motility, biofilm formation, and bacterial persistence, which was further validated by the results of transcriptome analysis. Mechanistic explorations revealed that Scu achieved its enzyme inhibitory activity predominantly through direct engagement with the active center of PPK1. Moreover, the survival rate of Galleria mellonella larvae was increased by about 35% with 20 mg/kg of Scu treatment. The remarkable therapeutic benefits of Scu were also observed in the mouse pneumonia model, shown mainly by reduced bacterial colonization, pathological lesions, and inflammatory factors. CONCLUSION: Our results revealed that Scu could attenuate the pathogenicity and persistence of A. baumannii by interfering with its important kinase PPK1.

Repurposing harmaline as a novel approach to reverse tmexCD1-toprJ1-mediated tigecycline resistance against klebsiella pneumoniae infections.

BACKGROUND: A novel plasmid-mediated resistance-nodulation-division (RND) efflux pump gene cluster tmexCD1-toprJ1 in Klebsiella pneumoniae tremendously threatens the use of convenient therapeutic options in the post-antibiotic era, including the "last-resort" antibiotic tigecycline. RESULTS: In this work, the natural alkaloid harmaline was found to potentiate tigecycline efficacy (4- to 32-fold) against tmexCD1-toprJ1-positive K. pneumoniae, which also thwarted the evolution of tigecycline resistance. Galleria mellonella and mouse infection models in vivo further revealed that harmaline is a promising candidate to reverse tigecycline resistance. Inspiringly, harmaline works synergistically with tigecycline by undermining tmexCD1-toprJ1-mediated multidrug resistance efflux pump function via interactions with TMexCD1-TOprJ1 active residues and dissipation of the proton motive force (PMF), and triggers a vicious cycle of disrupting cell membrane integrity and metabolic homeostasis imbalance. CONCLUSION: These results reveal the potential of harmaline as a novel tigecycline adjuvant to combat hypervirulent K. pneumoniae infections.

A proposed biomarker for human citric acid ester (CAE) exposure, and the potential disturbance on human lipid metabolism.

Citric acid esters (CAEs), as one class of important alternative plasticizers, have been proven to be ubiquitous in the environments, leading to an increasing concern regarding their potential health risk to humans. However, information regarding the biomarkers for human CAE biomonitoring is currently unknown. In the present study, we investigated the metabolism characteristics of CAEs by use of in vitro rat liver microsomes (RLMs) and in vivo mice. We observed that CAEs would undergo a rapid metabolism in both in vitro and in vivo conditions, implying that parent CAEs could be not suitable for biomonitoring of human CAE exposure. By use of high-resolution Orbitrap mass spectrometry (MS), ten molecules were tentatively identified as CAE potential metabolites on the basis of their MS and MS/MS characteristics, and CAEs could be metabolized via multiple pathways, i.e. hydrolyzation, hydroxylation, O-dealkylation. Further MS screening in human serum samples demonstrated that most of parent CAEs were not detectable, whereas numerous CAE metabolites were detected in the same batch of analyzed samples. Especially, one of metabolites of tributyl citrate (named with TBC-M1), exhibited a high detection frequency of 73.3%. By use of TBC-M1 as the biomarker of human CAE exposure, alteration of lipid metabolism was further examined in human serum. Interestingly, we observed statistically significant correlations between TBC-M1 levels and population characteristics (i.e., age, BMI, and drinking). Beyond that, we also observed statistically significant correlation between levels of TBC-M1 and lipid molecules (phosphatidylinositol (18:0/20:4) and sphingomyelin (d34:1)). Collectively, this study underscored the property of rapid metabolism of CAEs in exposed organism, and proposed a potential biomarker that could be greatly helpful for further investigating the human CAE exposure and understanding their potential health risks.

[Application of chromatographic retention time correction in untargeted screening].

OBJECTIVE: Chromatographic retention time correction is one of the important steps to effectively improve the accuracy of identification. This article proposed a strategy for untargeted screening of biological samples based on retention time correction. METHODS: A pre-treatment method for biological samples was established. The conditions of liquid chromatography and mass spectrometry were optimized. Fourteen compounds were selected as calibration agents. The retention time correction of different samples, different injection time, different brands of instruments, changing chromatographic column and changing mobile phase were investigated. RESULTS: Calibration agents had a wide coverage, good stability and no interference with sample determination. They could be uniformly distributed in the chromatogram in both positive and negative ion modes. The chromatogram was divided into several time intervals. Calibration agents in each time period were used for retention time linear correction, and the correction effects were good. CONCLUSION: The retention time correction method could eliminate the retention time drift caused by experimental conditions, improve the accuracy of qualitative analysis, and help to solve the problem of high false positive result based on mass spectrum information.

A new function of thymol nanoemulsion for reversing colistin resistance in Salmonella enterica serovar Typhimurium infection.

BACKGROUND: Adjuvant addition of approved drugs or foodborne additives to colistin might be a cost-effective strategy to overcome the challenge of plasmid-mediated mobile colistin resistance gene emergence, which poses a threat in the clinic and in livestock caused by infections with Gram-negative bacteria, especially carbapenem-resistant Enterobacteriaceae. METHODS: Chequerboard assay was applied to screen the colistin adjuvants from natural compounds. The killing-time curve, combined disc test and membrane permeation assay were conducted to identify the synergy efficacy of thymol and colistin in vitro. Thin-layer chromatography (TLC), LC-MS and fluorescence spectra were used to indicate the interaction of thymol and MCR-1. The potential binding sites were then investigated by molecular simulation dynamics. Finally, a thymol nanoemulsion was prepared with high-pressure homogenization as the clinical dosage form. RESULTS: Thymol presented an excellent synergistic effect in vitro with colistin against Salmonella enterica serovar Typhimurium and Escherichia coli bacteria. Thymol addition, forming a complex with MCR-1, might interfere with the efficacy of MCR-1. Moreover, thymol strengthened colistin activity associated with potentiating membrane damage, destroying the biofilm and enhancing reactive oxygen species-mediated oxidative damage. Thymol nanoemulsion combined with colistin remarkably prevented the intestinal damage caused by S. Typhimurium infection, resulting in a survival rate higher than 60%. CONCLUSIONS: This study achieved a promising thymol oral formulation as colistin adjuvant to combat S. Typhimurium infection, which could be used to extend the lifespan of colistin in clinical veterinary medicine.

Association between dietary approaches to stop hypertension (DASH) diet and hyperuricemia among Chinese adults: findings from a nationwide representative study.

BACKGROUND: Certain foods and food groups could positively or negatively impact serum uric acid (SUA) levels. However, evidence on the holistic dietary strategy to prevent and control hyperuricemia (HUA) development remains limited. OBJECTIVE: The aim of this research work was to explore the association of dietary approaches to stop hypertension (DASH) diet with SUA levels and odds of HUA among Chinese adults. METHODS: This research premise included 66,427 Chinese adults aged 18 and above who were part of the China Adult Chronic Disease and Nutrition Surveillance in 2015. Dietary consumptions were assessed via the household condiment weighing approach and a three-day, 24-hour dietary recall. Total fat, saturated fat, calcium, protein, potassium, cholesterol, magnesium, fiber, and sodium were all adopted to calculate the DASH score (score range, 0-9). The associations of DASH score with SUA levels and odds of HUA were evaluated using multiple linear and logistic regression models, respectively. RESULTS: We established that a higher DASH score was linked with a lower SUA levels (ß = - 0.11; 95% CI: - 0.12, - 0.1; p < 0.001) and odds of HUA (OR = 0.85; 95% CI: 0.83, 0.87; p < 0.001) after adjustment for age, sex, ethnicity, education status, marital status, health behaviours and health factors. The association of the DASH diet with odds of HUA was stronger among men (p-interaction = 0.009), non-Han Chinese (p-interaction< 0.001) as well as rural residents (p-interaction< 0.001). CONCLUSIONS: Our results illustrate that the DASH diet was remarkably negatively with SUA levels and odds of HUA in the Chinese adult population.

High-protein compound yogurt with quinoa improved clinical features and metabolism of high-fat diet-induced nonalcoholic fatty liver disease in mice.

Gut microbiota dysbiosis plays a crucial role in the occurrence and progression of nonalcoholic fatty liver disease (NAFLD), which may be influenced by nutritional supplementation. Quinoa, a type of pseudocereal, has gained prominence due to its high nutritional value and diverse applications. This study aimed to determine whether yogurt containing quinoa can ameliorate NAFLD and alleviate metabolic disorders by protecting against the divergence of gut microbiota. Our findings suggested that quinoa yogurt could significantly reduce the body weight gain and fat tissue weight of high-fat diet (HFD)-fed obese mice. In addition, quinoa yogurt significantly reduced liver steatosis and enhanced glucose homeostasis and insulin sensitivity. Additional research indicates that quinoa yogurt can reduce the levels of proinflammatory cytokines (i.e., tumor necrosis factor α, IL-1ß, and IL-6) and inhibit endotoxemia and systemic inflammation. The characteristics of the gut microbiota were then determined by analyzing 16S rRNA. In addition, we discovered that the gut microbiota was disturbed by HFD consumption. Particularly, intestinal probiotics and beneficial intestinal secretions were increased, leading to the expression of glucagon-like peptide-1 in the colon, contributing to NAFLD. Furthermore, endotoxemia and systemic inflammation in HFD-fed mice were restored to the level of control mice when they were fed yogurt and quinoa. Therefore, yogurt containing quinoa can effectively alleviate NAFLD symptoms and may exert its effects via microbiome-gut-liver axis mechanisms. According to some research, the role of the enteric-liver axis may also influence metabolic disorders to reduce the development of NAFLD.

Pattern of lifestyle behaviors and associated risk of being bullied at schools: A latent class analysis of 25,379 adolescents in Jiangsu Province of China.

School bullying is a worldwide problem. Although previous studies examined the association between different lifestyle behaviors and bullying victimization, the complex co-occurrence of these behaviors was not identified, and their association with the risk of being bullied remains unclear. We aimed to identify the behavioral patterns of adolescents and to explore their association with bullying victimization. This cross-sectional study employed data from the "Surveillance for Common Diseases and Health Risk Factors among Students" project implemented in Jiangsu Province of China in 2019, and a total of 25,379 school-enrolled students were included. We used a latent class analysis to identify behavioral patterns and a regression mixture model to explore various demographic characteristics, such as age, sex, and family structure in relation to bullying victimization across different patterns. We considered respondents having targeted behaviors, including smoking, alcohol consumption, illicit drug use, sugar consumption, no fruit consumption, low physical activity, electronic media use, and insufficient sleep. Four behavioral patterns were identified, including the "adolescents without apparent targeted behaviors" (19.65%), "substance and electronic media users" (12.76%), "typical electronic media users" (54.49%), and "typical substance users" (8.10%). The risk of being bullied was the highest in the "substance and electronic media users" (probability: 0.33), tripled that in "adolescents without apparent targeted behaviors" (odds ratio: 3.60, 95% confidence interval: 3.01-4.30). Risk of being bullied was reduced for those "substance and electronic media users" living with a nuclear family. Behavioral patterns and their association with being bullied differ between groups of school-aged adolescents. To better inform decision-making based on the current real-world findings, the implementation of bullying prevention programs could target specific behavioral patterns.

The Application of Cinnamon Twig Extract as an Inhibitor of Listeriolysin O against Listeria monocytogenes Infection.

As a major virulence factor of Listeria monocytogenes (L. monocytogenes), listeriolysin O (LLO) can assist in the immune escape of L. monocytogenes, which is critical for the pathogen to evade host immune recognition, leading to various infectious diseases. Cinnamon twig (CT), as a traditional medicine, has been widely used in clinics for multiple functions and it has exhibited excellent safety, efficacy and stability. There are few reports on the effects of the extracts of traditional medicine on bacterial virulence factors. CT has not been reported to be effective in the treatment of L. monocytogenes infection. Therefore, this study aims to explore the preventive effect of CT against L. monocytogenes infection in vivo and in vitro by targeting LLO. Firstly, a hemolysis assay and a cell viability determination are used to detect the effect of CT extract on the inhibition of the cytolytic activity of LLO. The potential mechanism through which CT extract inhibits LLO activity is predicted through network pharmacology, molecular docking assay, real-time polymerase chain reaction (RT-PCR), Western blotting and circular dichroism (CD) analysis. The experimental therapeutic effect of CT extract is examined in a mouse model infected with L. monocytogenes. Then, the ingredients are identified through a high-performance liquid chromatography (HPLC) and thin layer chromatography (TLC) analysis. Here we find that CT extract, containing mainly cinnamic acid, cinnamaldehyde, ß-sitosterol, taxifolin, catechin and epicatechin, shows a potential inhibition of LLO-mediated hemolysis without any antimicrobial activity. The results of the mechanism research show that CT extract treatment can simultaneously inhibit LLO expression and oligomerization. Furthermore, the addition of CT extract led to a remarkable alleviation of LLO-induced cytotoxicity. After treatment with CT extract, the mortality, bacterial load, pathological damage and inflammatory responses of infected mice are significantly reduced when compared with the untreated group. This study suggests that CT extract can be a novel and multicomponent inhibitor of LLO with multiple strategies against L. monocytogenes infection, which could be further developed into a novel treatment for infections caused by L. monocytogenes.

Acacetin attenuates Streptococcus suis virulence by simultaneously targeting suilysin and inflammation.

Streptococcus suis (S. suis), an important zoonotic pathogenic bacterium, can cause multiple diseases and fatal infections in both humans and animals. The emergence of highly virulent and extensively drug-resistant strains of S. suis has raised questions about the efficacy of available therapeutic agents, thereby necessitating novel therapeutic strategies. Suilysin (SLY) is one of the most essential determinants of virulence for the pathogenicity of S. suis capsular type 2 (SS2). In addition, inhibiting the excessive inflammatory response is a strategy to reduce the damage caused by SS2 infection. In this study, we identified acacetin as an effective inhibitor of SLY, which inhibited the oligomerisation of SLY without affecting bacterial growth. Furthermore, the addition of 4-16 µg/ml acacetin to the co-infection system of the cells reduced S. suis-induced inflammation by downregulating the activation of the MAPK signalling pathway, thereby alleviating the S. suis-mediated cell injury. Thus, in addition to the conventional antibiotic therapy, acacetin represent a potential drug candidate and strategy for the treatment of S. suis infections as it simultaneously inhibited the haemolytic activity of SLY and downregulated the inflammatory response.

Association between serum zinc concentrations and metabolic risk factors among Chinese children and adolescents.

The aim of the present study was to examine whether serum Zn concentrations were associated with metabolic risk factors in Chinese children and adolescents. This was a cross-sectional study including 3241 participants, aged 6 to 17 years, from Jiangsu, China. Metabolic risk factors included fasting glucose (FG), total cholesterol (TC), TAG, HDL-cholesterol, LDL-cholesterol, systolic blood pressure and diastolic blood pressure. Data were analysed using multi-variable linear regression and generalised additive models, which were adjusted for age, sex, high-sensitive C-reactive protein, estimated glomerular filtration rate, BMI and region of residence, to assess the associations of serum Zn concentrations with metabolic risk factors. We observed a negative association between serum Zn concentrations and FG (coefficient = -0·532; 95 % CI -0·569, -0·495; P < 0·001). Moreover, TC (coefficient = 0·175; 95 % CI 0·127, 0·222; P < 0·001), HDL-cholesterol (coefficient = 0·137; 95 % CI 0·082, 0·193; P < 0·001) and LDL-cholesterol (coefficient = 0·195; 95 % CI 0·128, 0·263; P < 0·001) were found to be positively associated with Zn levels. A generalised additive model showed that the negative association between serum Zn and FG was weak at lower serum Zn concentrations and was stronger with the increase in serum Zn concentrations. Additionally, a U-shaped association between serum Zn and TAG was observed. Serum Zn concentrations were associated with FG, TC, TAG, HDL-cholesterol and LDL-cholesterol levels in Chinese children and adolescents. Lower levels of serum Zn were more likely related to a poor metabolic status.

Detection of antibiotics in the urine of children and pregnant women in Jiangsu, China.

Exposure to low concentrations of antibiotics links to multiple health hazards, such as drug resistance of bacteria, and childhood obesity. In this study, seven antibiotics were measured in the urine of 107 children and 126 pregnant women in Jiangsu Province by ultra-performance liquid chromatography and tandem mass spectrometry (UPLC-MS/MS). The overall urinary antibiotics detection rate was 38.6%. Most (98.3%) of the participants' antibiotics concentrations were no more than 10 ng/mL. Children had a significantly higher detection rate than pregnant women (47.7% vs. 31.0%, P = 0.009), as well as the concentration (95th percentile: 6.49 vs. 4.08 ng/mL, P = 0.002). The detection rates of individual antibiotics ranged from 0.4% to 15.0%, and the concentrations ranged from lower than the limit of detection (LOD) through up to 31.96 ng/mL individually. Two or more antibiotics were detected in 11.2% of the urines. Tetracyclines were more frequently detected than phenicols (30.9% vs.12.4%). Oxytetracycline was the most frequently detected (15.0%). Multivariate logistic regression showed that consuming puffed food every day was associated with a significantly increased likelihood of detection, and higher concentration of overall antibiotics, and of doxycycline. Children were more likely to be detected of doxycycline and florfenicol, and to have elevated concentration of doxycycline, compared with pregnant women. This study highlights the relatively heavier antibiotics exposure in children, and a possible impact of puffed food on it, which needs to be warranted in future studies.

Isoalantolactone restores the sensitivity of gram-negative Enterobacteriaceae carrying MCR-1 to carbapenems.

Polymyxin B has been re-applied to the clinic as the final choice for the treatment of multidrug-resistant gram-negative pathogenic infections, but the use of polymyxin B has been re-assessed because of the emergence and spread of the plasmid-mediated mcr-1 gene. The purpose of this study was to search for an MCR inhibitor synergistically acting with polymyxin to treat the infection caused by this pathogen. In this study, we used the broth microdilution checkerboard method to evaluate the synergistic effect of isoalantolactone (IAL) and polymyxin B on mcr-1-positive Enterobacteriaceae. Growth curve analysis, time-killing assays and a combined disc test were used to further verify the efficacy of the combined drug. Colonization of the thigh muscle in mice, survival experiments and lung tissue section observations was used to determine the effect of synergy in vivo after Klebsiella pneumoniae and Escherichia coli infection. We screened a natural compound, IAL, which can enhance the sensitivity of polymyxin B to mcr-1-positive Enterobacteriaceae. The results showed that the combined use of polymyxin B and IAL has a synergistic effect on mcr-1-positive Enterobacteriaceae, such as K pneumoniae and E coli, not only in vitro but also in vivo. Our results indicate that IAL is a natural compound with broad application prospects that can prolong the service life of polymyxin B and make outstanding contributions to the treatment of gram-negative Enterobacteriaceae infections resistant to polymyxin B.

Association between adiposity measures and COPD risk in Chinese adults.

Bodyweight and fat distribution may be related to COPD risk. Limited prospective evidence linked COPD to abdominal adiposity. We investigated the association of body mass index (BMI) and measures of abdominal adiposity with COPD risk in a prospective cohort study.The China Kadoorie Biobank recruited participants aged 30-79 years from 10 areas across China. Anthropometric indexes were objectively measured at the baseline survey during 2004-2008. After exclusion of participants with prevalent COPD and major chronic diseases, 452 259 participants were included and followed-up until the end of 2016. We used Cox models to estimate adjusted hazard ratios relating adiposity to risk of COPD hospitalisation or death.Over an average of 10.1 years of follow-up, 10 739 COPD hospitalisation events and deaths were reported. Compared with subjects with normal BMI (18.5-<24.0 kg·m-2), underweight (BMI <18.5 kg·m-2) individuals had increased risk of COPD, with adjusted hazard ratio 1.78 (95% CI 1.66-1.89). Overweight (BMI 24.0-<28.0 kg·m-2) and obesity (BMI ≥28.0 kg·m-2) were not associated with an increased risk after adjustment for waist circumference. A higher waist circumference (≥85 cm for males and ≥80 cm for females) was positively associated with COPD risk after adjustment for BMI. Additionally, waist-to-hip ratio and waist-to-height ratio were positively related to COPD risk.Abdominal adiposity and underweight were risk factors for COPD in Chinese adults. Both BMI and measures of abdominal adiposity should be considered in the prevention of COPD.

Honokiol Restores Polymyxin Susceptibility to MCR-1-Positive Pathogens both In Vitro and In Vivo.

The emergence of the plasmid-mediated colistin resistance gene mcr-1 has led to serious multidrug-resistant (MDR) Enterobacteriaceae infections, which are a great threat to the clinic. This study aims to find an inhibitor of MCR-1 to reestablish the use of polymyxins against MDR Enterobacteriaceae infections. Here, we determined that the natural compound honokiol could enhance the efficacy of polymyxins against MDR Enterobacteriaceae infections by a checkerboard MIC assay, a time-kill assay, a combined disk test, Western blotting, molecular simulation dynamics, and mouse infection models. The MIC results indicated that honokiol can recover the sensitivity of polymyxins against MCR-1-positive Klebsiella pneumoniae and Escherichia coli (with a fractional inhibitory concentration index ranging from 0.09 ± 0.00 to 0.27 ± 0.06). Based on time-kill curve analysis, all of the tested bacteria were killed within 1 h following the combined therapy with honokiol and polymyxins. Molecular simulation dynamics results suggested that honokiol directly binds to the MCR-1 active region, reducing the biological activity of MCR-1. The combination of honokiol and polymyxins could increase the 40% protection rate and reduce the bacterial load on the thigh muscles of mice. Our study indicates that honokiol is a predominant natural compound whose combination therapy with polymyxins is very promising in future treatment options for MCR-1-positive Enterobacteriaceae infections.IMPORTANCE In the present study, honokiol could effectively inhibit the activity of MCR-1 and showed almost no cytotoxicity to MH-S cells. According to our results, the combination of honokiol and polymyxin had a clear synergistic effect against MCR-1-positive Enterobacteriaceae in vitro Combination therapy also showed a powerful therapeutic effect in vivo, which can significantly improve mouse livability, reduced the load of bacteria, and reduced pathological change. This combined therapy of small molecule compounds and antibiotics may not continue to induce new bacterial resistance, due to the fact that MCR-1 targeted by honokiol is not indispensable for the bacterial viability; on the other hand, it can reduce the dosage of combined antibiotics, and it is also a promising alternative therapy for the treatment of drug-resistant infections in the future.

The distribution of refraction by age and gender in a non-myopic Chinese children population aged 6-12 years.

BACKGROUND: The Prevalence of myopia is increasing in China. This study aimed to explore the distribution of spherical equivalent (SE) and its association with age, body mass index (BMI), gender in a non-myopic Chinese children population aged 6 to 12 years. METHODS: A total of 6362 students were recruited for ophthalmological investigation. Demographic and myopia related behavioral information was collected. SE value was measured by the Topcon RM-8900 or KR-800autorefractors. Potential independent risk factors were determined with Odds Ratio (OR) and 95% Confidence Interval (CI) by logistic regression analysis. We further constructed the nomogram model to predict future onset of myopia. RESULTS: Among the study population, 3900 (61.3%) were non-myopic. The prevalence of myopia is 38.0% for boys and 39.5% for girls. The average SE values were 0.50 ± 0.70 D for boys and 0.60 ± 0.80 D for girls. The mean SE values decreased with age, and the value of height and BMI took on a stable trend. Threshold values for myopia varied across age groups and gender. Paternal myopia (OR: 1.22, 95%CI: 1.01-1.48), near-work activities on weekends (2.56, 1.17-5.61), and outdoor activities (0.68, 0.54-0.86) were associated with potential myopic in students. CONCLUSION: A series of age-gender based SE threshold values were established to predict myopia in Chinese children aged 6 to 12 years. High risk factors for myopia included paternal myopia, near-work activities on weekends, and outdoor activities. Countermeasures are encouraged to reverse the increasing trend of myopia in children.

Pterostilbene, a Potential MCR-1 Inhibitor That Enhances the Efficacy of Polymyxin B.

We characterized the synergistic effect produced between pterostilbene and polymyxin B (fractional inhibitory concentration [FIC] index = 0.156 or 0.188) against MCR-producing Escherichia coli strains of both human and animal origins. The time-killing assays showed that either pterostilbene or polymyxin B failed to eradicate the mcr-1- and NDM-positive E. coli strain ZJ487, but the combination eliminated the strain by 1 h postinoculation. The survival rate of mice after intraperitoneal infections was significantly enhanced from 0% to 60% in the group in which combination therapy was applied.

Epigallocatechin gallate can attenuate human alveolar epithelial cell injury induced by alpha-haemolysin.

Staphylococcus aureus (S. aureus) is a common cause of hospital-acquired infection and has become an epidemic globally. Alpha-haemolysin (α-haemolysin), a pore-forming toxin, is one of the most important virulence factors secreted by most S. aureus strains. α-haemolysin monomers form a 232.4-kDa membrane-inserted heptamer by self-assembling to cause host cell lysis and death. Consequently, α-haemolysin plays a significant role in the pathogenesis of S. aureus, and it could be the target for the treatment of staphylococcal infection. In this study, epigallocatechin gallate (EGCg), a natural compound with little anti-S. aureus activity, was shown to reduce the haemolytic activity of α-haemolysin by inhibiting the self-assembly of the heptamer. When EGCg was added into a co-cultured system of human alveolar epithelial (A549) cells and bacterial suspension, α-haemolysin-induced cell injury was significantly attenuated. These results indicate that EGCg could effectively reduce the cytotoxicity of the toxin by interacting with α-haemolysin. This study provides the basis for the development of anti-virulence drugs for the treatment of S. aureus infection.

Hb level, iron intake and mortality in Chinese adults: a 10-year follow-up study.

Anaemia is prevalent in developing countries and is commonly Fe deficiency related. We aimed to assess the association between Fe status, Fe intake and mortality among Chinese adults. We prospectively studied 8291 adults aged 20-98 years with a mean follow-up of 9·9 years. All participants were measured for Hb at baseline in 2002. Food intake, measured by 3-d weighed food record (n 2832), and fasting serum ferritin were measured. We documented 491 deaths (including 192 CVD and 165 cancer deaths) during 81 527 person-years of follow-up. There was a U-shaped association between Hb levels and all-cause mortality. Compared with the second quartile of Hb (121 g/l), the first (105) and fourth quartile (144) had hazard ratios (HR) of 2·29 (95 % CI 1·51, 3·48) and 2·31 (95 % CI 1·46, 3·64) for all-cause mortality in women. In men, compared with third quartile of Hb (143 g/l), first (122) and fourth quartiles (154) had 61 and 65 % increased risk of all-cause mortality. Anaemia was associated with an increased risk of all-cause and CVD mortality in men but not in women after adjusting for potential confounders. Low and high Fe intake as percentage of Chinese recommended nutrient intake (RNI) were positively associated with all-cause mortality in women but not in men. In women, across quartiles of relative Fe intake, HR for all-cause mortality were 2·55 (95 % CI 0·99, 6·57), 1·00, 3·12 (95 % CI 1·35, 7·18) and 2·78 (95 % CI 1·02, 7·58). Both low and high Hb levels are related to increased risk of all-cause mortality. Both low and high intake of Fe as percentage of RNI was positively associated with mortality in women.

Morin Moderates the Biotoxicity of Pneumococcal Pneumolysin by Weakening the Oligomers' Formation.

Streptococcus pneumoniae (pneumococcus) is an important causative agent of acute invasive and non-invasive infections. Pneumolysin is one of a considerable number of virulence traits produced by pneumococcus that exhibits a variety of biological activities, thus making it a target of small molecule drug development. In this study, we aimed to evaluate the effect of morin, a natural compound that has no antimicrobial activity against S. pneumonia, is a potent neutralizer of pneumolysin-mediated cytotoxicity and genotoxicity by impairing oligomer formation, and possesses the capability of mitigating tissue damage caused by pneumococcus. These findings indicate that morin could be a potent candidate for a novel therapeutic or auxiliary substance to treat infections for which there are inadequate vaccines and that are resistant to traditional antibiotics.