Advances in Metabolism and Metabolic Toxicology of Quinoxaline 1,4-Di-N-oxides.

Quinoxaline 1,4-di-N-Oxides (QdNOs) have been used as synthetic antimicrobial agents in animal husbandry and aquaculture. The metabolism and potential toxicity have been also concerns in recently years. The metabolism investigations showed that there were 8 metabolites of Carbadox (CBX), 34 metabolites of Cyadox (CYA), 33 metabolites of Mequindox (MEQ), 35 metabolites of Olaquindox (OLA), and 56 metabolites of Quinocetone (QCT) in different animals. Among them, Cb3 and Cb8, M6, and O9 are metabolic residual markers of CBX, MEQ and OLA, which are associated with N → O reduction. Toxicity studies revealed that QdNOs exhibited severe tumorigenicity, cytotoxicity, and adrenal toxicity. Metabolic toxicology showed that toxicity of QdNOs metabolites might be related to the N → O group reduction, and some metabolites exhibited higher toxic effects than the precursor, which could provide guidance for further research on the metabolic toxicology of QdNOs and provide a wealth of information for food safety evaluation.

Recent advances of nanopore technique in single cell analysis.

Single cells and their dynamic behavior are closely related to biological research. Monitoring their dynamic behavior is of great significance for disease prevention. How to achieve rapid and non-destructive monitoring of single cells is a major issue that needs to be solved urgently. As an emerging technology, nanopores have been proven to enable non-destructive and label-free detection of single cells. The structural properties of nanopores enable a high degree of sensitivity and accuracy during analysis. In this article, we summarize and classify the different types of solid-state nanopores that can be used for single-cell detection and illustrate their specific applications depending on the size of the analyte. In addition, their research progress in material transport and microenvironment monitoring is also highlighted. Finally, a brief summary of existing research challenges and future trends in nanopore single-cell analysis is tentatively provided.

Identification and Prioritization of Organic Pollutants in Human Milk from the Yangtze River Delta, China.

Pollutants in human milk are critical for evaluating maternal internal exposure and infant external exposure. However, most studies have focused on a limited range of pollutants. Here, 15 pooled samples (prepared from 467 individual samples) of human milk from three areas of the Yangtze River Delta (YRD) in China were analyzed by gas chromatography quadrupole time-of-flight mass spectrometry. In total, 171 compounds of nine types were preliminarily identified. Among these, 16 compounds, including 2,5-di-tert-butylhydroquinone and 2-tert-butyl-1,4-benzoquinone, were detected in human milk for the first time. Partial least-squares discriminant analysis identified ten area-specific pollutants, including 2-naphthylamine, 9-fluorenone, 2-isopropylthianthrone, and benzo[a]pyrene, among pooled human milk samples from Shanghai (n = 3), Jiangsu Province (n = 6), and Zhejiang Province (n = 6). Risk index (RI) values were calculated and indicated that legacy polycyclic aromatic hydrocarbons (PAHs) contributed only 20% of the total RIs for the identified PAHs and derivatives, indicating that more attention should be paid to PAHs with various functional groups. Nine priority pollutants in human milk from the YRD were identified. The most important were 4-tert-amylphenol, caffeine, and 2,6-di-tert-butyl-p-benzoquinone, which are associated with apoptosis, oxidative stress, and other health hazards. The results improve our ability to assess the health risks posed by pollutants in human milk.

Correlations of IL-1 and IL-6 Gene polymorphisms with hypertrophic cardiomyopathy.

The purpose of this study was to explore the correlations of interleukin-1 (IL-1) and IL-6 gene polymorphisms with hypertrophic cardiomyopathy (HCM). A total of 200 patients with HCM were enrolled as disease group, and 200 healthy individuals were included as control group. Peripheral blood was collected from all subjects in both disease and control groups. Gene polymorphisms and serum expression levels of IL-1 and IL-6 were detected, and conjoint analysis was performed based on results of cardiac color Doppler ultrasound examination. The allele distribution of IL-1 rs1878320 showed a difference between disease and control groups (P=0.000). The frequency of the allele T was lower in disease group. The genotype distribution of IL-1 rs1878320 (P=0.001) and IL-6 rs1474347 (P=0.000) in disease group was different from that in control. The frequency of TC genotype of IL-1 rs1878320 was lower in disease group, and that of CA genotype of IL-6 rs1474347 was higher in disease group. There was a difference in the distribution of the dominant model of IL-6 rs1474347 between disease and control groups (P=0.021), and the frequency of CC + CA in the dominant model was 171 (0.855). The frequency of AC haplotype of IL-1 gene was overtly higher in disease group (P=0.000), while the frequency of AT haplotype was lower in disease group (P=0.000). The IL-1 rs1516792 polymorphism had an association with serum IL-1 level (P<0.05), the IL-1 level was notably increased in the patients with the genotype AA, and it was higher in disease group. The polymorphism of rs1878320 locus in IL-1 gene was correlated with interventricular septal (IVS) (P=0.047), and IVS was reduced in the patients with TC genotype. The polymorphism of rs1516792 locus in IL-1 gene was distinctly related to left ventricular outflow tract (LVOT) (P=0.041), and LVOT was lowered in the patients with GG genotype. The IL-6 rs2069831 polymorphism was associated with left ventricular ejection fraction (LVEF) (P=0.035), and LVEF declined in the patients with TT genotype. The IL-1 and IL-6 gene polymorphisms are correlated with the susceptibility and progression of HCM.

Pyrococcus furiosus argonaute based Alicyclobacillus acidoterrestrsis detection in fruit juice.

Alicyclobacillus acidoterrestris is the major threat to fruit juice for its off-odor producing characteristic. In this study, Pyrococcus furiosus Argonaute (PfAgo), a novel endonuclease with precise DNA cleavage activity, was used for A. acidoterrestrisdetection, termed as PAD. The partially amplified 16 S rRNA gene of A. acidoterrestris can be cleaved by PfAgo activated by a short 5'-phosphorylated single strand DNA, producing a new guide DNA (gDNA). Then, PfAgo was activated by the new gDNA to cut a molecular beacon (MB) with fluorophore-quencher reporter, resulting in the recovery of fluorescence. The fluorescent intensity is positively related with the concentration of A. acidoterrestris. The PAD assay showed excellent specificity and sensitivity as low as 101 CFU/mL, which can be a powerful tool for on-site detection of A. acidoterrestris in fruit juice industry in the future, reducing the economic loss.

Dual-Loading of Fe3O4 and Pd Nanoparticles on g-C3N4 Nanosheets Toward a Magnetic Nanoplatform with Enhanced Peroxidase-like Activity for Loading Various Enzymes for Visual Detection of Small Molecules.

Enzyme mimics now play a significant role in biochemistry. Especially, peroxidase mimics have been widely used for developing colorimetric sensors of blood glucose. The peroxidase mimics previously reported could not be recycled for reusing and may generate scattering to cause unwanted optical interference when it was used for fabricating colorimetric sensors. We herein prepared a broad-applicable and reusable magnetic enzyme-loading nanoplatform with enhanced peroxidase-like activity by simultaneously loading Fe3O4 nanoparticles (Fe3O4NPs) and palladium nanoparticles (PdNPs) on graphitic carbon nitride (g-C3N4) nanosheets (Fe3O4NPs/PdNPs/g-C3N4). The prepared Fe3O4NPs/PdNPs/g-C3N4 possesses stable and enhanced peroxidase-like activity and good enzyme-loading capacity and can be used to load various natural enzymes to form highly-efficient and stable double-active nanozyme for fabricating colorimetric sensors for the visual detection of small molecules. Especially, the magnetic feature facilitates the magnetic separation of Fe3O4NPs/PdNPs/g-C3N4 from sample solution, which is in favor of recycling and eliminating the optical interference caused by nanozyme in colorimetric sensors. The prepared Fe3O4NPs/PdNPs/g-C3N4 has been successfully used to load glucose oxidase (GOx) and cholesterol oxidase (Chox) to form magnetic peroxidase-GOx and peroxidase-Chox double-active nanozymes, which can be used to fabricate colorimetric methods for the detection of glucose and cholesterol, respectively, with a visual detection limit of 15 µM and a spectrometry detection limit of 1.0 µM. With the developed glucose and cholesterol detection methods, we have successfully detected glucose and cholesterol in serum with a recovery of 98-104% and a RSD (n = 5) < 5%. With high peroxidase-like activity, good stability, reusable features, and broad applicability of loading enzyme, the developed magnetic Fe3O4NPs/PdNPs/g-C3N4 provided a promising approach for fabricating cost-effective, sensitive, and simple colorimetric sensors for the visual detection of various small molecules.

Prevalence and Influencing Factors of Food Allergy in Global Context: A Meta-Analysis.

INTRODUCTION: This study was conducted to evaluate the prevalence and influencing factors of food allergy (FA) in different regions and populations. METHODS: The studies from January 2011 to December 2021 were searched through PubMed, Embase, Cochrane Library, and Web of Science databases. The prevalence of FA was evaluated by calculating the pooled effect estimates and their 95% confidence intervals (CIs). The odds ratio (OR) value was used to investigate the influencing factors of FA. Heterogeneity analysis among studies was performed using I2 analysis. Sensitivity analysis was performed to assess the stability of the results, and Begg's test was used to assess publication bias. RESULTS: A total of 105 published articles, including 3,318,608 participants, were involved in this study. The result indicated that the overall FA prevalence was 4.3% (95% CI: 0.038-0.047). The prevalence of FA was 4.2% in Asia (95% CI: 0.033-0.051), 3.2% in America (95% CI: 0.024-0.041), 4.8% in Europe (95% CI: 0.037-0.060), 1.6% in Africa (95% CI: 0.008-0.026), and 7.5% in Oceania (95% CI: 0.052-0.102). Milk (prevalence: 1.1%, 95% CI: 0.009-0.013) and egg (prevalence: 1.1%, 95% CI: 0.008-0.014) were the most common type of FAs. Male (OR: 1.289, 95% CI: 1.001-1.659), antibiotics exposure during pregnancy (OR: 1.221, 95% CI: 1.162-1.284), breastfeeding (OR: 1.349, 95% CI: 1.011-1.799), asthma (OR: 1.794, 95% CI: 1.443-2.230), eczema (OR: 5.121, 95% CI: 3.575-7.334), family history of atopic disease (OR: 1.893, 95% CI: 1.313-2.730), family history of FAs (OR: 2.096, 95% CI: 1.686-2.594), family history of atopic dermatitis (OR: 1.954, 95% CI: 1.645-2.322), family history of asthma (OR: 1.516, 95% CI: 1.370-1.678), and family history of allergic rhinitis/conjunctivitis (OR: 1.287, 95% CI: 1.191-1.392) increased the risk of FA. CONCLUSION: There were geographical differences in the prevalence of FA. Identification and nursing of FA high-risk populations should be strengthened to improve the quality of life.

Engineering an Enzymatic Cascade Catalytic Smartphone-Based Sensor for Onsite Visual Ratiometric Fluorescence-Colorimetric Dual-Mode Detection of Methyl Mercaptan.

Precise and reliable onsite detection of methyl mercaptan (CH3SH) is of great significance for environmental surveillance. Here, we synthesized a novel blue fluorescence nanozyme CeO2@TPE with high peroxidase-like activity by employing aggregation-induced emission (AIE) tetraphenylethene (TPE) to embed into hollow CeO2 nanospheres. In the presence of ethanol oxidase (AOX) and o-phenylenediamine (OPD), we engineered an enzymatic cascade activation ratiometric fluorescence-colorimetric dual-mode system AOX/CeO2@TPE + OPD toward CH3SH. In this design, CH3SH initiated AOX catalytic activity to convert it into H2O2 for activating the peroxidase-like activity of CeO2@TPE, producing •OH for oxidizing the naked-eye colorless OPD into deep yellow 2,3-diaminophenazine (DAP) with an absorption enhancement at ∼425 nm, companied by a new emission peak at ∼550 nm to match with the intrinsic emission at ∼441 nm for observing ratiometric fluorescence response, enabling a ratiometric fluorescence-colorimetric dual-mode analysis. Interestingly, both the ratiometric fluorescence and colorimetric signals could be gathered for being converted into the hue parameter on a smartphone-based sensor, achieving the onsite visual fluorescence-colorimetric dual-mode detection of CH3SH in real environmental media with acceptable results. This study gave a novel insight into designing target-responsive enzymatic cascade activation system-based efficient and reliable dual-mode point-of-care sensors for safeguarding environmental health.

Penetration of Perfluorooctanesulfonate Isomers and Their Alternatives from Maternal Blood to Milk and Its Associations with Chemical Properties and Milk Primary Components.

Perfluorooctanesulfonate (PFOS) and its alternatives, including chlorinated polyfluorinated ether sulfonates (Cl-PFESAs), are mainly detected per- and polyfluoroalkyl substances (PFAS) in human samples such as milk. However, the mechanism of their blood to milk transfer was not well studied. Here, 145 paired maternal serum and human milk samples were analyzed for six PFOS isomers and Cl-PFESAs to evaluate the transfer efficiency from maternal serum to human milk (TEHM/MS). Besides physicochemical properties, this study for the first time evaluated the influencing effects of the primary components in human milk (carbohydrate, lipid, and protein) on TEHM/MS of PFAS. No significant association was observed between TEHM/MS and the albumin binding affinity of the compounds (p = 0.601), but TEHM/MS was significantly negatively correlated with the logarithmic octanol-water partition coefficients (r2 = 0.853, p = 0.001), the logarithmic membrane-water partition coefficients (r2 = 0.679, p = 0.012), and the carbohydrate contents in human milk. The effect of carbohydrate was further confirmed using in vitro tests. The negative associations between TEHM/MS and hydrophobicity, membrane passive permeability, and the carbohydrate content in human milk consistently indicated that passive diffusion through the paracellular route might be the main transfer pathway for PFOS and Cl-PFESAs from blood to milk in humans.

6:2 Chlorinated Polyfluoroalkyl Ether Sulfonates Exert Stronger Thyroid Homeostasis Disruptive Effects in Newborns than Perfluorooctanesulfonate: Evidence Based on Bayesian Benchmark Dose Values from a Population Study.

Growing toxicologic evidence suggests that emerging perfluoroalkyl substances (PFASs), like chlorinated polyfluoroalkyl ether sulfonate (Cl-PFESA), may be as toxic or more toxic than perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA). However, further investigations are needed in terms of the human health risk assessment. This study examined the effects of emerging and legacy PFAS exposure on newborn thyroid homeostasis and compared the thyroid disruption caused by 6:2 Cl-PFESA and PFOS using a benchmark dose approach. The health effects of mixture and individual exposure were estimated using the partial least-squares (PLS) model and linear regression, respectively. A Bayesian benchmark dose (BMD) analysis determined the BMD value for adverse effect comparison between 6:2 Cl-PFESA and PFOS. The median (interquartile range) concentrations of 6:2 Cl-PFESA (0.573 [0.351-0.872] ng/mL), PFOS (0.674 [0.462-1.007] ng/mL), and PFOA (1.457 [1.034, 2.405] ng/mL) were found to be similar. The PLS model ranked the PFAS variables' importance in projection (VIP) scores as follows: 6:2 Cl-PFESA > PFOS > PFOA. Linear regression showed that 6:2 Cl-PFESA had a positive association with free triiodothyronine (FT3, P = 0.006) and triiodothyronine (T3, P = 0.014), while PFOS had a marginally significant positive association with FT3 alone (P = 0.042). The BMD analysis indicated that the estimated BMD10 for 6:2 Cl-PFESA (1.01 ng/mL) was lower than that for PFOS (1.66 ng/mL) in relation to a 10% increase in FT3. These findings suggest that 6:2 Cl-PFESA, an alternative to PFOS, has a more pronounced impact on newborns' thyroid homeostasis compared to PFOS and other legacy PFASs.

Concentrations, Profiles, and Health Risks of Organic Ultraviolet Filters in Eight Food Categories Determined through the Sixth Chinese Total Diet Study.

Ultraviolet (UV) filters are emerging contaminants that have been found in high concentrations in human tissues. Food intake is generally considered to be the primary route of human exposure to contaminants. In this study, 184 composite food samples, prepared from 4268 individual samples in eight categories collected from 23 Chinese provinces for the sixth Chinese total diet study, were analyzed. The total and median UV filter concentrations in food samples were 1.5-68.3 and 7.9 ng/g wet weight, respectively. The highest median concentrations were found in decreasing order in meat, cereals, and legumes. In total, 15 UV filters were analyzed. 2-Ethylhexyl salicylate, homosalate, and 2-ethylhexyl-4-methoxycinnamate were dominant and made median contributions of 34.1%, 22.6%, and 14.5%, respectively, and 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol contributed the median of 0.03%, of the total UV filter concentrations. The estimated total daily UV filter intake in animal-origin foods and total UV filter concentration in human milk from the same province were significantly correlated (r = 0.44, p < 0.05). Predicted absorption, distribution, metabolism, and elimination properties led to 10 UV filters being prioritized as most likely to be retained in human tissues. The prioritization results and toxicity assessments indicated that octocrylene and 2-ethylhexyl-4-methoxycinnamate have stronger effects in vivo and therefore require more attention than others.

Cadmium influence on lipid metabolism in Sprague-Dawley rats through linoleic acid and glycerophospholipid metabolism pathways.

Cadmium (Cd) is widely distributed in the environment and easy adsorbed by living organisms with adverse effects. Exposure to Cd-contaminated food may disrupt lipid metabolism and increase human health risk. To study the perturbation effect of Cd on lipid metabolism in vivo, 24 male Sprague-Dawley (SD) rats were randomly assigned four groups and treated by Cd chloride solution (0, 1.375 mg/kg, 5.5 mg/kg, 22 mg/kg) for 14 days. The characteristic indexes of serum lipid metabolism were analyzed. Afterwards, untargeted metabolomics analysis was applied to explore the adverse effects of Cd on rats by liquid chromatography coupled with mass spectrometry (LC-MS). The results revealed that Cd exposure obviously decreased the average serum of triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C) and caused an imbalance of endogenous compounds in the 22 mg/kg Cd-exposed group. Compared with the control group, 30 metabolites with significant differences were identified in the serum. Our results indicated that Cd caused lipid metabolic disorders in rats by disrupting linoleic acid and glycerophospholipid metabolism pathways. Furthermore, there were three kinds of remarkable differential metabolites-9Z,12Z-octadecadienoic acid, PC(20:4(8Z,11Z,14Z,17Z)/0:0), and PC(15:0/18:2(9Z,12Z)), which enriched the two significant metabolism pathways and could be the potential biomarkers.

Prevalence and distribution of acute gastrointestinal illness in the community of China: a population-based face-to-face survey, 2014-2015.

BACKGROUND: The true incidence of acute gastrointestinal illness in China is underrecognized by surveillance systems. The aims of this study were to estimate the incidence and prevalence of self-reported AGI in the community of China, and to investigate sociodemographic and epidemiological determinants of AGI. METHODS: We conducted a 12-months cross-sectional population-based survey in eight provinces of China during 2014-2015. The survey determined the prevalence and incidence of acute gastrointestinal illness (AGI) in the total permanent resident population in China according to the census of the population in 2010. The random multilevel population sample was stratified by geographic, population, and socioeconomic status. We used a recommended case definition of AGI, with diarrhea (three loose or watery stools) and/or any vomiting in a four-week recall. A face-to-face survey was conducted by selecting the member in the household with the most recent birthday. RESULTS: Among 56,704 sampled individuals, 948 (1,134 person-time) fulfilled the case definition; 98.5% reported diarrhea. This corresponds to 2.3% (95% CI:1.9%-2.8%) of an overall standardized four-week prevalence and 0.3 (95% CI: 0.23-0.34) episodes per person-year of annual adjusted incidence rate. There was no significant difference between males and females. The incidence rates were higher among urban residents, and in the spring and summer. In the whole study period, 50% of the cases sought medical care, of which 3.9% were hospitalized and 14.3% provided a biological sample for laboratory identification of the causative agent. Children aged 0-4 and young adults aged 15-24, people living in rural areas and people who traveled frequently had higher prevalence of AGI. CONCLUSION: Results showed that AGI represents a substantial burden in China, and will contribute to the estimation of the global burden of AGI. Complemented with data on the etiologies of AGI, these estimates will form the basis to estimate the burden of foodborne diseases in China.

Prevalence of food allergy in the Chinese population: A systematic review and meta-analysis of population-based studies.

Background: The prevalence of food allergy is increasing and varies among different populations. Study on the food allergy prevalence is very limited in China. Objective: To assess the prevalence of food allergy in the Chinese population by using systematic evaluation and meta-analysis. Methods: A literature search for population-based epidemiologic study on food allergy in China was conducted in several Chinese and English medical literature data bases. Pooled prevalence data and 95% confidence intervals were calculated to estimate the prevalence of food allergy in China. Subgroup analyses were performed to eliminate and explain the heterogeneity, and also to obtain the prevalence of pooled food allergy in different populations. Results: The overall food allergy prevalence ranged from 4.0% to 8.2%. Subgroup analysis showed a trend of overall increase of food allergy, which varied between 4.4% and 9.9%; The common allergic foods were determined to be mango, shrimp, egg, milk, and crab, with the prevalence of 1.9%, 1.5%, 1.4%, 1.3%, 1.3%, respectively; There is a lack of epidemiologic studies on food allergy in some regions and the overall prevalence of food allergy varied from region to region in China. Conclusion: This study revealed that the prevalence of food allergy in the Chinese population ranged from 4.0% to 8.2%; Food allergy prevalence varied by gender, age, and region. This study highlighted the need for collaborative studies of food allergy with the same rational methods to minimize potential bias caused by methods and techniques. Findings of this study may provide baseline data and scientific reference for improving policies on prevention and control of food allergy.

[Associations of a mixture of eleven endocrine disruptors in human urine with the risk of papillary thyroid cancer].

OBJECTIVE: To examine the associations of human exposure to a mixture of 11 endocrine disruptors(EDCs) with the risk of papillary thyroid cancer(PTC), and to identify the priority of these EDCs. METHODS: EDCs were determined in fasting urine specimens to represent human exposure. Logistics regressions were performed to examine the associations between individual EDC and PTC risk. Bayes kernel machine regression was applied to examine the associations between the mixture of EDCs and PTC risk. Weighted quantile sum(WQS) regression and LASSO regression were performed to identify the main contributor. RESULTS: In the multivariate logistic regression model, after adjusting for a series of variables, 11 endocrine disruptors were statistically significantly correlated with the risk of PTC(P<0.05). In BKMR models, the mixture of EDCs was positively correlated with the risk of PTC(P<0.05). The weight and coefficient of mono(2-ethyl-5-hydroxyhexyl) phthalate(MEHHP) was 0.62 and 1.58 in WQS and LASSO models, respectively, which were much higher than those of the other EDCs. CONCLUSION: Combined exposure to o a variety of EDCs might promote the risk of PTC, and MEHHP was identified as the main contributor.

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) (ß=-0.27, 95% confidence interval (CI) [-0.41, -0.14]), total triiodothyronine (TT3) (ß=-0.02 95% CI [-0.03, -0.01]), free T4 (fT4) (ß=-0.02, 95% CI [-0.03, -0.01]), and free T3 (fT3) (ß=-0.04, 95% CI [-0.07, -0.01]), and mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) and monoethyl phthalate (MEP) positively associated with TT4 (ß=0.24, 95% CI [0.01, 0.48]) and fT4 (ß=0.02, 95% CI [0.01, 0.04]), respectively. Moreover, we observed significant dose-response relationships between TT4 and the mixture of 11 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.

Generic Enrichment of Organic Contaminants in Human Biomonitoring: Application in Monitoring Early Life Exposures to Fipronil via Breast Milk.

In human biomonitoring, a high-throughput extraction and enrichment method for multiple types of organic contaminants at the part-per-trillion level is critical yet challenging, especially in the limited sample volume. When large-scale sample analysis is involved, low cost is often what we should consider. We describe a generic and straightforward cold-induced liquid-liquid extraction (CI-LLE) strategy to meet this need. Current methods for extracting and enriching organic contaminants from biological samples often require multistep sample processing, including specially tailoring the extraction solvent or adsorbents. This method uses cold-induced phase separation to achieve the extraction and enrichment of studied organic contaminants by adjusting the proportion of acetonitrile/water mixture, so as to integrate the extraction and enrichment in one step without additional reagents and adsorbents. In this study, fipronil insecticide was used as a representative compound to determine the key parameters of CI-LLE. The optimized CI-LLE procedure allowed simultaneous extraction and enrichment of studied organic contaminants, providing excellent enrichment factors (especially for lipophilic organic contaminants). CI-LLE was further applied in monitoring early life exposures of fipronil in 109 breast milk samples. This study provided baseline data on fipronil levels in breast milk samples from China. For infants, exposure to fipronil is of concern. In summary, CI-LLE provides a feasible solution for a generic, efficient, and low-cost preparation of biological samples and promotes high-throughput batch analysis of organic contaminants for large-scale human biomonitoring.

Photoresponsive DNA-Modified Magnetic Bead-Assisted Rolling Circle Amplification-Driven Visual Photothermal Sensing of Escherichia coli.

The development of facile, reliable, and accurate assays for pathogenic bacteria is critical to environmental pollution surveillance, traceability analysis, prevention, and control. Here, we proposed a rolling circle amplification (RCA) strategy-driven visual photothermal smartphone-based biosensor for achieving highly sensitive monitoring of Escherichia coli (E. coli) in environmental media. In this design, E. coli could specifically bind with its recognition aptamer for initiating the RCA process on a magnetic bead (MB). Owing to the cleaving of UV irradiation toward photoresponsive DNA on MB, the RCA products were released to further hybridize with near-infrared excited CuxS-modified DNA probes. As a result, the photothermal signal was enhanced by RCA, while the background was decreased by UV irradiation and magnetic separation. The correspondingly generated photothermal signals were unambiguously recorded on a smartphone, allowing for an E. coli assay with a low detection limit of 1.8 CFU/mL among the broad linear range from 5.0 to 5.0 × 105 CFU/mL. Significantly, this proposed biosensor has been successfully applied to monitor the fouling levels of E. coli in spring water samples with acceptable results. This study holds great prospects by integrating a RCA-driven photothermal amplification strategy into a smartphone to develop accurate, reliable, and efficient analytical platforms against pathogenic bacteria pollutions for safeguarding environmental health.

CRISPR-Cas systems mediated biosensing and applications in food safety detection.

Food safety, closely related to economic development of food industry and public health, has become a global concern and gained increasing attention worldwide. Effective detection technology is of great importance to guarantee food safety. Although several classical detection methods have been developed, they have some limitations in portability, selectivity, and sensitivity. The emerging CRISPR-Cas systems, uniquely integrating target recognition specificity, signal transduction, and efficient signal amplification abilities, possess superior specificity and sensitivity, showing huge potential to address aforementioned challenges and develop next-generation techniques for food safety detection. In this review, we focus on recent progress of CRISPR-Cas mediated biosensing and their applications in food safety monitoring. The properties and principles of commonly used CRISPR-Cas systems are highlighted. Notably, the frequently coupled nucleic acid amplification strategies to enhance their selectivity and sensitivity, especially isothermal amplification methods, as well as various signal output modes are also systematically summarized. Meanwhile, the application of CRISPR-Cas systems-based biosensors in food safety detection including foodborne virus, foodborne bacteria, food fraud, genetically modified organisms (GMOs), toxins, heavy metal ions, antibiotic residues, and pesticide residues is comprehensively described. Furthermore, the current challenges and future prospects in this field are tentatively discussed.

Concentrations, Compound Profiles, and Possible Sources of Organic UV Filters in Human Milk in China.

Ultraviolet (UV) filters are of great concern due to their wide occurrence, bioaccumulation, and toxicity. Little is known about human exposure to UV filters. A total of 3467 individual human milk samples from 24 Chinese provinces were collected during 2017-2019. The concentrations of 12 UV filters in 100 pooled milk samples were determined. The total UV filter concentration was 78-846 (mean 235 ± 120) ng/g lipid weight. The highest and lowest total mean concentrations were for samples from Qinghai and Sichuan provinces, respectively. A significant positive correlation was found between UV radiation levels and UV concentrations in the samples. The dominant UV filters were 2-(2-hydroxy-5-methylphenyl) benzotriazole (UV-P) and ethylhexyl methoxycinnamate (EHMC), which contributed means of 32 and 22%, respectively, to the total concentrations. Plastic products and sunscreens were probably the sources of UV-P and EHMC in the human milk from China, respectively. The mean 2-(3,5-di-tert-amyl-2-hydroxyphenyl) benzotriazole (UV-328) concentration was 2.6 ± 2.6 ng/g lipid weight. The UV filter profiles were similar to profiles for samples from Japan, the Philippines, and Switzerland but not for samples from Korea and Vietnam. The estimated daily UV filter intake for breastfed infants was below the corresponding reference dose. This was the first large-scale study of UV filters in human milk and will help assess the risks posed.