Application of UPLC-MS/MS Method for Analyzing B-vitamins in Human Milk

Objective To determine ten B-vitamins in human milk by ultra-high performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）. Methods The pretreated human milk samples were adequately separated and quantified within 11 min by UPLC-MS/MS with an Acquity UPLC HSS T3 column （2.1×100 mm, 1.8 μm）. The mobile phase was a gradient of 2.5 mmol/L ammonium formate aqueous solution and acetonitrile at a flow rate of 0.35 mL/min. Stable isotope internal standards were used in the analysis, to correct for the method variability, including matrix and ionization effects. The homogenized human milk samples were deproteinzed using methanol, unknown contaminants were extracted with diethyl ether and hydrophobic phase was discarded. The analytes were monitored via ESl＋ionization and detected in multiple reaction monitoring （MRM） with three acquisition functions. Results Calibration curves ranged from 0.5-160 ng/mL （thiamin, riboflavin, biotin, nicotinic acid, pyridoxine, pyridoxamine, pyridoxal）, and 2.5-800 ng/mL （pantothenic acid, FAD and nicotinamide） （R^2=0.990-0.999）. The relative recovery ranged from 80.1% to 120.2%; accuracy was determined to be 98.3% to 108.0%. Intra-day and inter-day variation were 3.4%-19.9% and 5.9%-18.1%, respectively. The limit of quantification （LOQ） for all vitamins was between 0.25 and 3 lag/L. Conclusion This method was successfully applied for simultaneous analysis of ten B-vitamins in human milk.

Serum Ferritin and the Risk of Metabolic Syndrome:A Systematic Review and Dose-Response Meta-Analysis of Cross-sectional Studies

Objective This study aims to assess the dose-response relationship between serum ferritin(SF)and metabolic syndrome(MetS)in the two sexes.Methods We searched for articles on PubMed,the Cochrane Library,EMBASE,and the Web of Science databases that were published from 1950 to 2020.The summary odds ratio(OR)and 95%confidence interval(CI)of the association between SF and MetS were estimated using a random-effects model through a meta-analysis.Based on the methods described by Greenland and Longnecker,we explored the dose-response relationship between the two sexes.Results This study included 14 studies and 74,710 samples.The results of the classical meta-analysis showed that SF was positively associated with MetS(OR=1.77,95%CI:1.59–1.98).Regarding the components of MetS(8 studies included),the results showed that SF was positively associated with abdominal obesity(OR=1.42,95%CI:1.24–1.62),elevated fasting plasma glucose(OR=1.84,95%CI:1.50–2.25),elevated blood pressure(OR=1.17,95%CI:1.08–1.26),elevated triglycerides(OR=2.09,95%CI:1.72–2.54),and reduced high-density lipoprotein cholesterol(OR=1.33,95%CI:1.19–1.49).In the linear dose-response meta-analysis,the ORs of males,females,and postmenopausal females were 1.14(95%CI:1.13–1.16),1.32(95%CI:1.26–1.39),and 1.34(95%CI:1.22–1.47),respectively.Conclusions Our study shows that SF is significantly and positively associated with MetS,and the risk in the male population is higher than that in the female population.This finding also supports the recommendation of using SF as an early warning marker of MetS.

Coronavirus disease 2019 outbreak in Beijing's Xinfadi Market, China: a modeling study to inform future resurgence response

Background:A local coronavirus disease 2019(COVID-19)case confirmed on June 11,2020 triggered an outbreak in Beijing,China after 56 consecutive days without a newly confirmed case.Non-pharmaceutical interventions(NPIs)were used to contain the source in Xinfadi(XFD)market.To rapidly control the outbreak,both traditional and newly introduced NPIs in eluding large-scale management of high-risk populations and expanded severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)PCR-based screening in the general population were conducted in Beijing.We aimed to assess the effectiveness of the response to the COVID-19 outbreak in Beijing's XFD market and inform future response efforts of resurgence across regions.

Transformation of sulfamethazine during the chlorination disinfection process: Transformation,kinetics, and toxicology assessment

Various disinfection byproducts(DBPs) form during the process of chlorination disinfection,posing potential threats to drinking water safety and human health. Sulfamethazine(SMT),the most commonly used and frequently detected veterinary antibiotic, was investigated in detail with regard to its transformation and kinetics in reactions with free available chlorine(FAC). Using liquid chromatography coupled to quadrupole time-of-flight tandem mass spectrometry, several DBPs were identified based on different confidence levels, and a variety of reaction types, including desulfonation, S–N cleavage, hydroxylation, and chlorine substitution, were proposed. The kinetic experiments indicated that the reaction rate was FAC-and pH-dependent, and SMT exhibits low reactivity toward FAC in alkaline conditions. The DBPs exhibited a much higher acute toxicity than SMT, as estimated by quantitative structure activity relationship models. More importantly, we observed that the FAC-treated SMT reaction solution might increase the genotoxic potential due to the generation of DBPs. This investigation provides substantial new details related to the transformation of SMT in the chlorination disinfection process.

Cholera Caused by a New Clone of Serogroup O1 Vibrio cholerae-Beijing Municipality,China,June 2021

Several lineages have been identified in the population of serogroup O1 Vibrio cholerae(V.cholerae)(1-3).The strains,which were responsible for the ongoing seventh cholera pandemic,were in Lineage 2.Nearly all the V.cholerae strains in this lineage carried genes coding cholera toxin(ctxAB)(1-2).Lineage 3b consists of strains isolated from different continents and the vast majority of strains in this lineage lack the ctxAB genes.

Effect of Earlier Vaccination and a Two-Dose Varicella Vaccine Schedule on Varicella Incidence—Beijing Municipality,2007-2018

Summary What is already known about this topic?The World Health Organization(WHO)varicella vaccines position paper states that countries where varicella is an important public health burden could consider introducing varicella vaccine(VarV)in the routine childhood immunization program(1).VarV has been available for many years in China but is not included in most routine immunization programs in China.

Perception of the COVID-19 Epidemic and Acceptance of Vaccination Among Healthcare Workers Prior to Vaccine Licensure——Beijing Municipality,China,May-July 2020

Summary What is already known about this topic?The coronavirus disease 2019(COVID-19)vaccine development has been progressing,but acceptance of the new vaccines by healthcare workers(HCWs)was not well known prior to approval of COVID-19 vaccines in China.What is added by this report?

Association between nutritional and physical factors and anemia among schoolchildren aged 5 to 11 years in Beijing

To the Editor:Previous studies paid less attention on the reasons of anemia in schoolchildren,particularly in a relatively well-off area,which might hamper policy design for anemia control.Thus,the present study would explore the reasons for anemiain schoolchildren aged 5to 11 years in Beijing based on personal data including dietary intake and serum biomarkers of nutrients.

Norovirus Detection in Environmental Samples from Norovirus Outbreaks in Schools and Kindergartens—Beijing Municipality,China,October–December 2020

What is already known on this topic?The norovirus has often caused outbreaks in schools and kindergartens,but minimal research has been performed on environmental contamination during norovirus outbreaks in schools and kindergartens.What is added by this report?This report conveys the norovirus detection rates and viral loads in different environmental sites in 45 norovirus outbreaks in Beijing Municipality from October to December 2020.What are the implications for public health practice?The evidence presented here can instruct professionals and the public to sample and disinfect key locations of the environment purposefully when responding to norovirus outbreaks.

Evaluation of the Integrated Information System for Brucellosis Case Diagnosis and Management-Inner Mongolia Autonomous Region,China,2019

What is already known about this topic?Wulanchabu City Center for Endemic Disease Prevention and Control had established and used a Brucellosis Integrated Information System(BIIS)since 2013.However,it had not been systematically evaluated and promoted so far.What is added by this report?The BIIS had significantly improved the efficiency of brucellosis reporting and provided convenience for follow-up management of cases,which was valuable for finishing completely routine therapy.However,the stability of the system needs to be improved.What are the implications for public health practice?The results of the BIIS assessment demonstrated its advantages and disadvantages,which could provide some evidence for its implementation in other areas of China.

Human exposure to a mixture of endocrine disruptors and serum levels of thyroid hormones:A cross-sectional study

Exposure to endocrine disruptors(EDCs) could disrupt thyroid hormone homeostasis. However, human epidemiological studies reported inconsistent observations, and scarce information on the effect of a mixture of chemicals. The aim of the present study was to examine the associations of multiple chemicals with thyroid hormones among adults from China. We measured serum levels of thyroid hormones and urinary levels of 11 EDCs, including six phthalate metabolites, bisphenol A(BPA), bisphenol F(BPF), bisphenol S(BPS), perchlorate, and thiocyanate among 177 healthy adults without occupational exposure. Associations of multiple urinary analytes with serum thyroid hormones were examined by performing general linear regression analysis and bayesian kernal machine regression analysis. These EDCs were detected in almost all samples. After adjusting for various covariates, we observed only BPF significantly associated with total thyroxin(TT4)(β=-0.27, 95% confidence interval(CI) [-0.41,-0.14]), total triiodothyronine(TT3)(β=-0.02 95% CI [-0.03,-0.01]), free T4(fT4)(β=-0.02, 95% CI [-0.03,-0.01]), and free T3(fT3)(β=-0.04, 95% CI [-0.07,-0.01]), and mono-(2-ethyl-5-oxohexyl) phthalate(MEOHP) and monoethyl phthalate(MEP) positively associated with TT4(β=0.24, 95% CI [0.01, 0.48]) and fT4(β=0.02, 95% CI [0.01, 0.04]), respectively. Moreover, we observed significant dose-response relationships between TT4 and the mixture of11 EDCs, and BPF was the main contributor to the mixture effect, suggesting the priority of potential effect of BPF on disrupting thyroid function under a real scenario of human exposure to multiple EDCs. Our findings supported the hypothesis that human exposure to low levels of EDCs could alter thyroid hormones homeostasis among non-occupational healthy adults.

Attitudes of vaccination service providers to the SARS-CoV-2 intranasal spray vaccine during the SARS-CoV-2 pandemic in China:A cross-sectional study

To the Editor:Intranasal spray vaccines(ISVs)can produce cellular immunity against severe acute respiratory syndrome virus 2(SARS-CoV-2)variants and have good safety and protective effects.[1]However,the attitudes of vaccination service providers toward ISVs have rarely been studied.This study investigated the attitudes of service providers towards vaccination processes that require optimization and improvement.

Characteristics in the Distribution of Chronic Benzene Poisoning Associated Industries-6 PLADs, China, 2005−2019

Summary What is already known on this topic?Starting in the early 1950s,the main industries in China associated with chronic benzene poisoning(CBP)included painting,pharmaceuticals,and shoemaking.However,because of rapid socioeconomic development,the distribution of industries associated with CBP likely changed.

Products of methotrexate during chlorination

Methotrexate （MTX） is a cytotoxic drug widely used in the treatment of tumors, autoimmune diseases and severe asthma, jen00883This drug has been frequently detected in the aquatic environment with concentrations up to μg/L levels. The MTX present in environmental water might be transformed and removed during chlorination disinfection treatment. In this work, the fate of MTX during aqueous chlorination was investigated in laboratory batch experiments, and the transformation products of MTX were identified. Aqueous solutions of MTX （1 mg/L） were chlorinated by sodium hypochlorite solution at room temperature under neutral pH conditions. Chlorinated products were pre-concentrated with solid-phase extraction （SPE） cartridges and determined by liquid chromatography electrospray ionization tandem mass spectrometry （LC-ESI-MS/MS）. The reaction of MTX chlorination exhibited pseudo-first-order kinetics and the half-life time of MTX degradation was calculated to be 1.65 min, when the initial chlorine concentration was 2 mg/L. Two chlorinated MTX congeners, 4-amino-3-chlorinated-N10-methylpteroylglutamic （monochloro-MTX） and 4-amino-3,5-dichloro-N10-methylpteroylglutamic （dichloro-MTX） were found in the chlori- nated solution. Monochloro-MTX was successfully fractionated by high performance liquid chromatography （HPLC） and its structure was further identified using 1H nuclear magnetic resonance （NMR） analysis. The presence of the two products in real hospital wastewater was then examined and both compounds were detected. Finally, the effects of MTX and monochloro-MTX on the cell cycle progression in vitro were evaluated using zebrafish liver cell line. It was found that both compounds could inhibit the proliferation of zebrafish liver cells through S phase arrest and their effects on the cell cycle profile had no significant difference.

Risk communication in the post-Fukushima era

In the long-term phases,clear risk communication in the post-Fukushima era is necessary and significant.It is the most urgent in this post-accident phase is for residents to access to all the information available within the scope of current knowledge in order to support their life decisions.For full recovery,authorities,specialists,international organizations,media,and the public will need to work together.The speed of innovation in risk communication should catch up to the development speed of the internet.Long-term communication will be necessary.Learning about the Fukushima nuclear accident experience is essential for the prevention and risk communication of possible accidents in the future.

Industry Distribution Characteristics of Benzene-Induced Leukemia—7 PLADs,China,2005–2019

Summary What is already known about this topic?In the 1980s.benzene-induced leukemia(BIL)mainly occurred in shoemaking and painting industries.Now the industry distribution of benzene-induced leukemia may have changed over time.What is added by this report?BlL cases mainly occurred in the manufacturing industry from 2005-2019,especially in private enterprises and small/medium-sized enterprises.The industry with the largest number of new cases of BIL was the general and special equipment manufacturing.The number of leukemia cases in emerging industries such as computer/electronic product manufacturing was found to be increasing.What are the implications for public health practice?Strengthening supervision and regulation of manufacturing,especially of small/medium-sized enterprises and emerging manufacturing industry,may be effective in reducing BIL.