Humoral and cellular immune responses induced by serogroup W135 meningococcal conjugate and polysaccharide vaccines.

Investigating the mechanisms by which W135 meningococcal conjugate (PSW135-TT) activates adaptive immune responses in mice can provide a comprehensive understanding of the immune mechanisms of bacterial polysaccharide conjugate vaccines. We compared B-cell and T-cell immune responses immunized with W135 meningococcal capsular polysaccharides (PSW135), tetanus toxoid (TT) and PSW135-TT in mice. The results showed that PSW135-TT could induce higher PSW135-specific and TT-specific IgG antibodies with a significant enhancement after two doses. All serum antibodies immunized with PSW135- TT had strong bactericidal activity, whereas none of the serum antibodies immunized with PSW135 had bactericidal activity. Besides, IgM and IgG antibodies immunized with PSW135-TT after two doses were positively correlated with the titer of bactericidal antibodies. We also found Th cells favored Th2 humoral immune responses in PSW135-TT, PSW135, and TT-immunized mice, especially peripheral blood lymphocytes. Furthermore, PSW135-TT and TT could effectively activate bone marrow derived dendritic cells (BMDCs) and promote BMDCs to highly express major histocompatibility complex Ⅱ (MHCⅡ), CD86 and CD40 molecules in mice, whereas PSW135 couldn't. These data verified the typical characteristics of PSW135-TT and TT as T cell dependent antigen (TD-Ag) and PSW135 as T cell independent antigen (TI-Ag), which will be very helpful for further exploration of the immune mechanism of polysaccharide-protein conjugate vaccines and improvement of the quality of bacterial polysaccharide conjugate vaccines in future.

A foodborne outbreak linked to Bacillus cereus at two middle schools in a rural area of Chongqing, China, 2021.

Bacillus cereus (B. cereus) is a common cause of foodborne illness. An outbreak of acute gastrointestinal illness occurred at two middle schools in a rural region of Chongqing, China, in 2021. This study aimed to elucidate the outbreak's characteristics, identify risk factors, and determine the source of contamination. A retrospective cohort study and an environmental investigation were conducted. Vomit samples, anal swabs, and food samples were collected and tested by RT-PCR for 18 species of bacteria and viruses, including B. cereus. Positive samples of B. cereus underwent biochemical experiments and bacterial quantification. A total of 198 cases were reported in this outbreak, with an attack rate of 24.63%. The main symptoms were vomiting (100%), bellyache (83.33%), and dizziness (62.63%). The retrospective cohort study showed a significant association between the outbreak and rice noodles provided by a nearby food manufacturer (RR = 39.63, p < 0.001). B. cereus was detected in 20 vomit samples, three anal swabs, and seven rice noodles samples, with a count exceeding 103 CFU/g. These findings strongly suggested that the outbreak was linked to B. cereus-contaminated rice noodles. Enhancing food safety surveillance and promoting health measures among schools and food manufacturers in rural areas is crucial to prevent similar incidents in the future in Chongqing, China.

[Probabilistic risk assessment of dietary exposure to lead among Chongqing residents].

OBJECTIVE: To investigate lead contamination in commercial foods in Chongqing City, and to assess the health risk of dietary lead exposure of residents in Chongqing City. METHODS: Lead concentration data was obtained from the food safety risk monitoring system, which included a total of 2347 lead-containing food samples in 11 categories in Chongqing from 2016 to 2020. Consumption data was derived from the China Health and Nutrition Survey Project in Chongqing in 2018(3 day, 24 h dietary recall survey). The dietary exposure to lead of residents in Chongqing was calculated by the Monte Carlo simulation method and the margin of exposure(MOE) method was used to evaluate the health risk of the population. RESULTS: The average content of lead in 2347 food samples from 11 categories ranged from 0.0328 to 0.0363 mg/kg, with an overall detection rate of 58.5%. For people aged between 3-6, 7-17, 18-59, and ≥ 60 years, the mean dietary lead intakes in Chongqing were 0.935-1.070, 0.600-0.684, 0.367-0.416, 0.369-0.419 µg/(kg·BW·d), respectively; and the high levels of dietary lead exposure(P95) were 1.642-1.852, 1.147-1.299, 0.651-0.729, 0.659-0.740 µg/(kg·BW·d), respectively. MOE values for lead were less than 1 for age groups 3-6 and 7-17 years. Mean MOE values for lead were greater than 1 for ages 18 to 59 and ≥ 60. Cereals and their products, vegetables and their products, and meat and meat products were the main sources of dietary lead exposure, accounting for more than 85% of the total dietary lead exposure. CONCLUSION: There are potential health risks of lead for residents in Chongqing.

Disease burden contributed by dietary exposure to aflatoxins in a mountainous city in Southwest China.

Introduction: Aflatoxins (AFT) identified as a Group 1 human carcinogen naturally contaminate various types of food and could increase the risk of hepatocellular carcinoma (HCC) through dietary intake. Chongqing municipality is located in Southwest China with subtropical monsoon climate which is conducive to AFT contamination in crops. However, the burden of HCC caused by the dietary exposure of the population in Chongqing to AFT has not been quantified. Methods: The burden of HCC was estimated in terms of Disability Adjusted Life Year (DALY) using FDA-iRISK software. Dietary exposure to AFT in three food categories including grain and its products, nuts and seeds, and spices was assessed. Results: The lifetime average daily dose (LADD) of AFT exposure for the population ranged from 2.40 to 8.25 ng/kg bw/day and 9.51 to 15.10 ng/kg bw/day at the mean and heavy (P95) AFT contamination levels, respectively. Among the three food categories, grain and its products contributed most to AFT exposure of the population. The estimated DALYs related to HCC induced by AFT were 162,000-556,000 and 641,000-1,020,000; the DALY rates were 6.47-22.20 and 25.59-40.72 per 100,000 persons per year; and the population attribution fractions (PAF) were 1.68-5.78% and 6.66-10.60%. Discussion: Although the burden of HCC caused by dietary AFT was estimated to be relatively low among the population, the overall health burden might be underestimated owing to the uncertainties of this dataset. Thus, the overall health burden associated with AFT intake should still be of concern in further studies.

The Mediation and Moderation Effect Association among Physical Activity, Body-Fat Percentage, Blood Pressure, and Serum Lipids among Chinese Adults: Findings from the China Health and Nutrition Surveys in 2015.

Physical activity (PA) is of benefit and particularly important for cardiovascular disease risk factors as being sedentary becomes a lifestyle habit. Research into Chinese complex association among physical activity, body-fat percentage (BF%), blood pressure, and serum lipids is limited. The present study is based on an observational study among adults (>18 years old) residing in fifteen provinces in China. Data of 10,148 adult participants in the 2015 China Health and Nutrition Survey (CHNS) were analyzed. The simple mediation effect models with covariates were utilized to assess the association among PA and blood pressure or serum lipids, and BF% was played as a mediator. The serial multiple-mediator models with covariates were constructed to the further analysis of the relationship between PA and blood pressure, and BF% was the mediator 1 and blood lipids were the mediator 2. Based on the above hypothesis, the moderated mediation models with covariates were used to analyze the association among PA, BF%, and blood pressure; in addition, BF% was used as the mediator and blood lipids played as the moderator. In the simple mediation models, the model with a dependent variable was high-density lipoprotein cholesterol (HDL-C) or low-density lipoprotein cholesterol (LDL-C); BF% was played as the partly mediation effect and the proportion of contribution was 0.23 and 0.25, respectively. In the serial multiple-mediator models, blood lipids, as the second mediator, played the mediation effect; however, the effect was smaller than the BF%. In the moderated mediation model, blood lipids had the moderation effect as the moderator variable. HDL-C played a moderating role in the latter pathway of the "PA→BF%→SBP/DBP" mediation model, and LDL-C/TC played a moderating role in the direct effect of the "PA→BF%→DBP". In conclusion, BF% played a mediating role in the relationship between PA and blood pressure. HDL-C, LDL-C, and TC were more likely to act as moderating variables in the mediation model "PA→BF%→SBP/DBP". PA could directly and indirectly benefit to control the CVD risk factors simultaneously.

A novel vaccine formulation candidate based on lipooligosaccharides and pertussis toxin against Bordetella pertussis.

Pertussis is a severe human respiratory tract infectious disease caused by Bordetella pertussis that primarily affects infants and young children. However, the acellular pertussis vaccine currently administered can induce antibody and Th2 immune responses but fails to prevent the nasal colonization and transmission of B. pertussis, causing a resurgence of pertussis, so improved pertussis vaccines are urgently needed. In this study, we created a two-component pertussis vaccine candidate containing a conjugate prepared from oligosaccharides and pertussis toxin. After demonstrating the ability of the vaccine to induce a mixed Th1/Th2/Th17 profile in a mouse model, the strong in vitro bactericidal activity and IgG response of the vaccine were further demonstrated. In addition, the vaccine candidate further induced efficient prophylactic effects against B. pertussis in a mouse aerosol infection model. In summary, the vaccine candidate in this paper induces antibodies with bactericidal activity to provide high protection, shorten the duration of bacterial existence, and further reduce disease outbreaks. Therefore, the vaccine has the potential to be the next generation of pertussis vaccines.

[Breast milk intake of Chinese infants aged 0-5 months in 2019-2021].

OBJECTIVE: To describe the breast milk intake of infants aged 0-5 months in China and its trends, and to analyze the effects of feeding mode, gender and regions on breast milk intake. METHODS: Data were extracted from Ministry of Science and Technology's basic resource survey project "China's 0-18-year-old children's nutrition and health system survey and application" project. Caregivers were face to face interviewed to collect the basic information of infants. Weighing method was used to measure 24 hourly breast milk intake of infants aged 0-5 months in China. The rank sum test was used to compare the differences in breast milk intake between groups, the Spearman rank sum test was used to analyze the trend of breast milk intake with increasing age, and the general linear regression model was used to analyze the effects of gender and region on breast milk intake. RESULTS: The mean breast milk intake of exclusively breastfed infants aged 0-5 months was 800.1 g/d, ranging from 696.4 to 937.7 g/d. Breast milk intake increased with age and remained stable at 5 months(ß=29.6, P=0.009). There was a statistically significant difference in breast milk intake among infants in different month age groups(χ~2=17.96, P=0.003). Infants aged 0-5 months who are exclusively breastfed were fed 8 times in 24 hours, the breast milk intake per each time is 103.4-152.5 g, the duration of each feeding is 20.4-24.6 min, and the breast milk intake per minute is 4.4-7.0 g. Except for 5 months of age, there was no gender difference in the 24-hour breast milk intake of exclusively breastfed infants aged 0 to 4 months(P>0.05). Except for 4-month-old exclusively breastfed infants, there was no regional differences in the breast milk intake of others(t=-4.25, P<0.001). In the mixed feeding group, breast milk + complementary feeding group and breast milk + formula powder + complementary feeding group, the breast milk intake of infants aged 0-5 months were 341.1-496.7 g, 239.1-742.7 g and 90.0-508.0 g, respectively. CONCLUSION: In 2019-2021, infants aged 0-5 months in China Breast milk intake increased with age, and remained stable at 5 months. The breast milk intake of infants aged 0-5 months in different regions or genders is similar except for individual months. The introduction of formula or complementary food directly affects the intake of breast milk in infants.

Longitudinal Association between Physical Activity, Blood Lipids, and Risk of Dyslipidemia among Chinese Adults: Findings from the China Health and Nutrition Surveys in 2009 and 2015.

Physical activity is needed in today's highly sedentary society. Research into Chinese trends with respect to the longitudinal association between changes in physical activity (PA) and dyslipidemia (DL) is limited. The present study assessed PA and PA-related changes associated with the level of serum lipids, and the risk of dyslipidemia stratified by gender, via a population-based longitudinal observational study among adults (>18 years old) residing in nine provinces in China. Data of 3380 adult participants, gleaned from two surveys in 2009 and 2015 used by the China Health and Nutrition Survey (CHNS), were analyzed. Three-level random intercept growth models were used to calculate the associations between total physical activity (TPA), the four activity subtypes, and changes in the level of blood lipids. Three-level logistic regression models were utilized to assess the association between TPA and the risk of DL. The highest level of TPA was observed to correlate with the lowest prevalence of DL. Compared with the lowest level of TPA, the highest level of TPA increases the concentration of HDL-C (ß = 0.050, 95% CI = 0.005, 0.096) in males, and also reduces the risk in males of having low HDL-C by 31% (OR = 0.69, 95% CI = 0.52, 0.91). Occupational PA was positively associated with higher HDL-C levels in both genders (males: ß = 0.004, 95% CI = 0.002, 0.007; females: ß = 0.002, 95% CI = 0.000, 0.004), and leisure-time physical activity (LTPA) was negatively associated with TG levels in males. Increasing TPA benefited HDL-C levels in males, irrespective of the level of basic TPA of individuals. Physical activity (especially occupational PA) was superior in positively influencing HDL-C in males, but not in females. Leisure-time physical activity needs to be increased substantially in order to increase TPA to levels that would be beneficial to blood lipid levels and DL, irrespective of baseline TPA levels.

[Association of beverages intake with myopia among 11-14-year-old Chinese children in 2019-2021].

OBJECTIVE: To describe beverages intake and its association with myopia among 11-14-year-old children in China. METHODS: Multi-stage stratified cluster random sampling was used and children aged 11 to 14 years were selected from 28 cities and rural areas in 14 provinces in China, and a total of 12 397 children were included in this study. Information including demographic characteristics, myopia status, dietary intake, physical activity, screen time, sleep duration were collected from questionnaire survey. RESULTS: During 2019-2021, the prevalence of myopia among children aged 11 to 14 in China was 45.0%. The median beverages intake was 42.7 g/d. Children who did not drink beverages and whose beverages intake was <150 g/d and ≥150 g/d accounted for 42.8%, 44.8% and 48.4%, respectively. Multivariate Logistic regression analysis showed that girls' beverages intake ≥150 g/d was still a risk factor for the prevalence of myopia after controlling for confounding factors such as age, area, physical activity, screen time, sleep duration and intake of sugary food(OR=1.24, 95%CI 1.08-1.42, P<0.05). Among children with myopia, mild myopia, moderate and above myopia accounted for 71.6% and 28.4% among boys and 73.8% and 26.3% among girls, respectively. There was no statistically significant regression between beverages intake and myopia in boys and girls regardless of whether confounding factors were adjusted(P >0.05). CONCLUSION: Children's beverages intake was generally common in China in 2019-2021. Children who consumed higher beverages were more likely to have myopia than that did not consume beverages.

Poisoning Associated with Consumption of a Homemade Medicinal Liquor - Chongqing, China, 2018.

On May 3, 2018, Chongqing Center for Disease Control and Prevention (CQCDC) received a report of 15 persons with numbness of the tongue or limbs and vomiting of unknown etiology; all ill persons had attended an adult birthday luncheon in Bishan District, Chongqing municipality, in southwest China. Initial reports indicated that one person had died. Within 2 hours, CQCDC and Western Chinese Field Epidemiology Training Program staff members launched an investigation that included identification of cases, laboratory testing of drinks, and patient interviews to identify the cause of what appeared to be a poisoning. Among the 15 cases, five persons died. The investigation of this apparent mass intoxication implicated a homemade alcoholic beverage produced from a highly toxic flowering plant in the genus Aconitum used in traditional Chinese medicine. Although the risk of aconite toxicity is known, approximately 5,000 cases of aconite poisoning incidents were reported in China, Germany, Japan, and other countries during 1993-2005; most cases of fatal poisoning occurred in China (1). This event highlights the importance of enforcing and complying with existing regulations regarding sale and purchase of Aconitum species (also known as wolfbane), and of dissemination of critical public health messages.

[Status of intakes of cereals and tubers among the adults in Chongqing City in 2010-2012].

OBJECTIVE: To analyze the status of consumption of cereal and tuber and its impact on macronutrients in among Chongqing City adults. METHODS: Data were collected from 2010-2012 China National Nutrition and Health Survey Surveillance. Multi-stage cluster random sampling was used to collect data among 1435 adults residents in 4 surveillance sites of China National Nutrition and Health Survey in Chongqing City. The number of male was 639, female was 796. The dietary investigation survey method of24-hour recall for three consecutive days were used to collect information on cereal and tuber intakes. Standardization was performed based on the Chinese population data published by National Statistics Bureau in 2009. The cereal and tuber intakes were calculated after weight adjustment with complex sampling. RESULTS: The average consumption of cereal and tuber was 323. 6 g( d. person) for Chongqing City adults in2010-2012. The proportion of energy from the cereal and tuber were 46. 5% and 2. 9%. The proportion of protein from the cereal was 40. 1%. The residents in urban had a lower intake( 280. 8 g) and proportion of energy of cereal and tuber( 37. 6%) than that of rural( 370. 2 g, 62. 1%), so doalso in the proportion of protein from the cereal( urban 28. 9%, rural 53. 9%). CONCLUSION: The intake of cereal and tuber level of the adult residents of in Chongqing City is lower than the national. The residents in urban had a lower intake than that in rural.

Impacts of extremely high temperature and heatwave on heatstroke in Chongqing, China.

Few studies have reported the quantitative association between heat and heatstroke (HS) occurrence, particularly in China. The aim of this study was to quantitatively assess the association between high temperature/heatwave and HS occurrence in Chongqing. The daily HS data from 2009 to 2013 of Chongqing were extracted from Chongqing Center for Disease Control and Prevention. A Zero-inflated Poisson regression model (ZIP) with a logistic distribution was used to quantitatively analyze the impacts of the daily maximum temperature (Tmax) over the threshold on HS occurrence by gender, age, and severity of HS, after controlling for covariates including day of the week (DOW), relative humidity, and daily temperature range. Lag effects up to 10 days were analyzed. Heatwave intensity, which was classified into four levels according to the quartile of its values, was calculated by Tmax multiplied the duration of a heatwave. The excess risk of HS during heatwave with different intensity was analyzed. The Tmax threshold for HS was 34 °C in Chongqing. After adjusting for potential confounders, strong associations and age-specific lag effects between Tmax and daily HS occurrence were observed. The impacts of Tmax on total HS lasted for 7 days (lag0-6), with the highest excess risk (ER) value of 30.5% (95% CI 23.6 and 37.8%) on lag0 with each 1 °C increment in Tmax over the threshold. A slightly stronger temperature-HS association was detected in male compared to female. The population over 65 years had the highest ER and the younger adults aged 19-35 and 35-55 years also showed significant heat-HS associations. The number of daily cases increased with the increasing of duration of heatwave and the peak value occurred on the eleventh day of the heatwave. The excess risk of HS during the heatwave with 1 to 4 level of intensity increased by 2.54, 2.97, 5.61, and 11.3 times, respectively, as compared with that of non-heatwave. Extreme heat is becoming a huge threat to public health due to the strong temperature-HS associations in Chongqing. Climate change with increasing temperatures may make the situation worse. Our results can provide reference for developing and improving relevant public health strategies and early extreme weather and health warning system to prevent and reduce the health risks due to extreme weather and climate change in Chongqing.

[Influence of daily ambient temperature on mortality and years of life lost in Chongqing].

OBJECTIVE: To evaluate the influence of extreme ambient temperature on mortality and years of life lost (YLL) in Chongqing. METHODS: The daily mortality, meteorology and air pollution index data in Chongqing from the 1(st) January 2010 to the 31(st) December 2013 were collected. Distributed lag non-linear model (DLNM) was used to assess the influence of daily ambient temperature on daily number of deaths and daily YLL respectively. The delayed and cumulative effects of extreme temperature on sex, age, and cause-specific mortality were also assessed. RESULTS: The relationships between ambient temperature and non-accidental, cardiovascular disease and respiratory disease mortalities and YLL were U-shaped or W-shaped. The effect of heat was obvious on that day, peaked on day 7, and lasted for two weeks, whereas the effect of cold was obvious a week later and lasted for a month. As 1 ℃ increase of ambient temperature, the cumulative relative risks (CRR) of high temperature across lag 0-7 days on non-accidental, respiratory disease and cardiovascular disease mortalities were 1.05 (95%CI: 1.03-1.07), 1.08 (95%CI: 1.05-1.11) and 1.05 (95%CI: 1.01-1.09) respectively. The effects of heat on YLL for each cause were 23.81 (95%CI: 12.31-35.31), 14.34 (95%CI: 8.98-19.70) and 4.43 (95%CI: 1.64-7.21), respectively. On cold days, 1 ℃ decrease of ambient temperature was correlated with an increase in CRR of 1.06 (95%CI: 1.04-1.08), 1.09 (95%CI:1.06-1.12) and 1.06 (95%CI: 1.02-1.11) from lag 0 to 14 for non-accidental, respiratory disease and cardiovascular disease mortalities, respectively. The estimated YLL were 23.34 (95%CI: 10.04-36.64), 16.39 (95%CI: 10.19-22.59) and 2.61 (95%CI: -0.61-5.82). People aged ≥65 years tend to have higher CRR and YLL than those aged <65 years. On high temperature days, the CRR in women was higher than that in men, while the YLL in women was lower than that in men. On low temperature days, both the CRR and YLL in women were higher than those in men. CONCLUSIONS: Both high and low ambient temperature have adverse health effects. People aged ≥65 years are more sensitive to both high and low ambient temperature. Younger men are more sensitive to high ambient temperature and women and elder men are sensitive to low ambient temperature. It is necessary to take targeted measures to protect the population in Chongqing from the adverse influence of extreme ambient temperature.

Extremely cold and hot temperatures increase the risk of diabetes mortality in metropolitan areas of two Chinese cities.

BACKGROUND: Numerous studies have reported the association between ambient temperature and mortality. However, few studies have focused on the effects of extreme temperatures on diabetes mortality, particularly in China. The objective of the present study was to assess the effects of extremely cold and hot temperatures on diabetes mortality in urban areas of Harbin and Chongqing in China to provide scientific evidence for public health policy implementation to respond to challenges in diabetes mortality because of extreme temperature events. METHODS: A double threshold B-spline distributed lag non-linear model (DLNM) was used to investigate the effects of extremely cold and hot temperatures on diabetes mortality from lag 0 to 30 days, after controlling for potential confounders including air pollutants. The unit risk, which is the elevated cumulative risk of diabetes mortality caused by each 1 °C change in extremely cold and hot temperatures during certain lag days, was estimated for extreme cold and heat using simple regression analysis. RESULTS: Significant associations between both extreme hot and cold temperatures and diabetes mortality were observed in Harbin and Chongqing for different lag lengths. In Harbin, the extreme cold effects on diabetes mortality were delayed by three days and lasted for six days (lag 3-8), with the highest risk (RR 95% CI: 1.223,1.054-1.418 for -23 °C) at lag 5. The hot effects were delayed one day and lasted for three days (lag 1-3), with the peak RR (1.343: 1.080-1.670 for 37 °C) at lag 2. In Chongqing, the cold effects on diabetes mortality were delayed by seven days and lasted for four days (lag 7-10), with the highest risk (1.201: 1.006-1.434 for 4 °C) at lag 7. The hot effects peaked (1.811: 1.083-3.027 for 41 °C) at lag 0 and lasted for 2 days (lag 0-1). The unit risk for cold and hot effects was 12.9% (95% CI: 2.5-33.7%) and 16.5% (95% CI: 3.8-39.1%) in Harbin and 12.5% (95% CI: -4.7 to 47.5%) and 19.7% (95% CI: 3.9-48.5%) in Chongqing, respectively. CONCLUSIONS: The results indicate that both extremely cold and hot temperatures increase diabetes mortality in different manners in Harbin and Chongqing. Diabetes education programs should include information on either managing or combating the effects of extreme hot and cold weather.