Brain structure and functional connectivity linking childhood cumulative trauma to COVID-19 vicarious traumatization.

BACKGROUND: The COVID-19 pandemic has caused some individuals to experience vicarious traumatization (VT), an adverse psychological reaction to those who are primarily traumatized, which may negatively impact one's mental health and well-being and has been demonstrated to vary with personal trauma history. The neural mechanism of VT and how past trauma history affects current VT remain largely unknown. This study aimed to identify neurobiological markers that track individual differences in VT and reveal the neural link between childhood cumulative trauma (CCT) and VT. METHODS: We used structural and resting-state functional magnetic resonance imaging before the pandemic to identify prospective brain markers for COVID-related VT by correlating individuals' VT levels during the pandemic with the gray matter volume (GMV) and seed-based resting-state functional connectivity (RSFC) and examined how these brain markers linked CCT to VT in a sample of general young adults (N = 115/100). RESULTS: Whole-brain GMV-behavior correlation analysis showed that VT was positively associated with GMV in the right dorsolateral prefrontal gyrus (DLPFC). Using the cluster derived from the GMV-behavior correlation analysis as the seed region, we further revealed that the RSFC between the right DLPFC and right precuneus was negatively associated with VT. Importantly, the right DLPFC volume and DLPFC-precuneus RSFC mediated the effect of CCT on VT. These findings remained unaffected by factors such as family socioeconomic status, other stressful life events, and general mental health. CONCLUSIONS: Overall, our study presents structural and functional brain markers for VT and highlights these brain-based markers as a potential neural mechanism linking CCT to COVID-related VT, which has implications for treating and preventing the development of trauma-related mental disorders.

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.

Neuroanatomical signatures associated with dispositional optimism predict COVID-19-related posttraumatic stress symptoms.

The COVID-19 pandemic has been increasingly documented to cause negative impacts on mental health outcomes, e.g. posttraumatic stress symptoms (PTSS). Dispositional optimism ("optimism" hereinafter), a crucial psychological characteristic defined by positive expectancies for future outcomes, is considered to provide remarkable protection against PTSS. Accordingly, this study was designed to identify neuroanatomical signatures of optimism and further examine the mechanism through which optimism protects against COVID-19-specific PTSS. Here, 115 volunteers from a general population of university students completed MRI scans and optimism tests before (October 2019-January 2020) and after (February-April 2020) the onset of the COVID-19 pandemic. Whole-brain voxel-based morphometry analysis showed that a region from the dorsal anterior cingulate cortex (dACC) to the dorsomedial prefrontal cortex (dmPFC) was associated with optimism. Further seed-based structural covariance network (SCN) analysis using partial least-squares correlation found an optimism-linked SCN covarying with the combined dACC and dmPFC (the dACC-dmPFC). Additionally, mediation analyses revealed that the dACC-dmPFC volume and its SCN impacted COVID-19-specific PTSS through optimism. Our findings deepen the understanding of optimism and have the potential to identify vulnerable individuals during the COVID-19 pandemic or similar future events, as well as to guide optimism-related neural interventions to prevent and alleviate PTSS.

[Determination of six bisphenols in human urine by ultra-high performance liquid chromatography-tandem mass spectrometry].

OBJECTIVE: To develop and validate a solid phase extraction-ultra-high performance liquid chromatography-tandem mass spectrometry method for the determination of six bisphenols(bisphenol S, bisphenol F, bisphenol A, 2, 2'-methylenediphenol, bisphenol AF, bisphenol AP) in urine. METHODS: After enzymolysis of urine sample, the target substances were quickly purified and extracted by WAX solid phase extraction column. On ACQUITY BEH C_(18) column(2.1 mm×100 mm, 1.7 µm), the mobile phase of water and methanol was used to separate. Finally, multi-reaction detection was carried out under electrospray negative ion scanning, and quantification was carried out by internal standard method. RESULTS: The correlation coefficients(r) of the target compounds were all more than 0.998 in the range of 0.1-50.0 ng/mL, the linearity was good, and the detection limits were all lower than 0.1 ng/mL. The recoveries of the three standard concentrations(0.5, 5.0 and 50.0 ng/mL) were all between 80% and 120%, and the relative standard deviation was less than 20%(n=5). The standard reference material was detected and the concentration was within the reference range. CONCLUSION: This method can be used to detect six bisphenols in urine quickly and accurately, is suitable for the trace analysis of bisphenol compounds in human urine.

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.

Thyroid-Disrupting Effects of Exposure to Fipronil and Its Metabolites from Drinking Water Based on Human Thyroid Follicular Epithelial Nthy-ori 3-1 Cell Lines.

Fipronil is a broad-spectrum insecticide used for plants and poultry. Owing to its widespread use, fipronil and its metabolites (fipronil sulfone, fipronil desulfinyl, and fipronil sulfide), termed FPM, can be frequently detected in drinking water and food. Fipronil can affect the thyroid function of animals, but the effects of FPM on the human thyroid remain unclear. We employed human thyroid follicular epithelial Nthy-ori 3-1 cells to examine combined cytotoxic responses, thyroid-related functional proteins including the sodium-iodide symporter (NIS), thyroid peroxidase (TPO), deiodinases I-III (DIO I-III), and the nuclear factor erythroid-derived factor 2-related factor 2 (NRF2) pathway induced by FPM of 1-1000-fold concentrations detected in school drinking water collected from a heavily contaminated area of the Huai River Basin. Thyroid-disrupting effects of FPM were evaluated by examining biomarkers of oxidative stress and thyroid function and tetraiodothyronine (T4) levels secreted by Nthy-ori 3-1 cells after FPM treatment. FPM activated the expression of NRF2, HO-1 (heme oxygenase 1), TPO, DIO I, and DIO II but inhibited NIS expression and increased the T4 level of thyrocytes, indicating that FPM can disrupt the function of human thyrocytes through oxidative pathways. Given the adverse impact of low FPM concentrations on human thyrocytes, supportive evidence from rodent studies, and the critical importance of thyroid hormones on development, the effects of FPM on the neurodevelopment and growth of children warrant priority attention.

[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.

[Determination of 25-hydroxyvitamin D in serum by pre-column derivatization-stable isotope labeling-ultra performance liquid chromatography-quadrupole electrostatic field orbitrap high-resolution mass spectrometry].

OBJECTIVE: To establish a rapid and accurate method for the determination of 25-hydroxyvitamin D_3(25(OH)D_3) and 25-hydroxyvitamin D_2(25(OH)D_2)in serum by pre-column derivatization with stable isotope labeling and ultra performance liquid chromatography-quadrupole electrostatic field orbitrap high-resolution mass spectrometry, which could be used to diagnose vitamin deficiency and to assess the nutritional status of vitamin D in the population. METHODS: The serum samples with isotopic internal standard were extracted by mixed extraction solvent(ethyl acetate∶hexane = 2∶1, V/V), centrifuged and dried by the nitrogen blowing, and derivatized with 4-phenyl-1, 2, 4-triazoline-3, 5-dione(PTAD). The reaction products were separated on a BEH C_(18) column(2.1 mm×50 mm, 1.7 µm), and eluted with a 0.1% formic acid/water solution-acetonitrile gradient. The mass spectrometry was performed in positive electrospray ionization(ESI~+) and parallel reaction monitoring(PRM) for the detection of the targets, and quantified by isotope internal standard. RESULTS: The limits of detection both for 25(OH)D_3 and 25(OH)D_2 were 0.01 ng/mL and the limits of quantification were 0.03 ng/mL. The concentration series of 25(OH)D_2 ranged from 0.5 to 40.0 ng/mL and the concentration series of 25(OH)D_3 ranged from 2.5 to 200.0 ng/mL. The recoveries(n=5) were 95.7%-101.3% for 25(OH)D_3, and 98.7%-108.6% for 25(OH)D_2, with the relative standard deviations(RSDs) of 0.5%-4.9% and 2.2%-3.4%, respectively. The accuracy of the determination of 25(OH)D_3 and 25(OH)D_2 in Level 2 serum of the 25(OH)D standard reference material NIST SRM 972a was 104.8% and 94.9%, respectively. The M(P25, P75)serum levels of 25(OH)D_3 and 25(OH)D_2 for 116 pregnant women at the first trimester from Beijing were 25.7(20.8, 32.6) ng/mL and 0.8(0.4, 1.1) ng/mL, respectively. CONCLUSION: This method is highly sensitive, qualitatively accurate and suitable for evaluation and monitoring the nutritional status of vitamin D in the population.

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.

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.

Comprehensive Evaluation of Dietary Exposure and Health Risk of Polychlorinated Naphthalenes.

Intake from food is considered an important route of human exposure to polychlorinated naphthalenes. To our knowledge, several studies have quantified dietary exposure but only in European countries and measuring only a few of the 75 congeners. In addition, the influence of source diversity on human exposure has seldom been assessed. We analyzed 192 composite food samples composed of 17,280 subsamples from 24 provinces in China to measure the concentrations of polychlorinated naphthalenes and estimate their daily intake and potential health risks on a national scale. The estimated cancer risk was in the range of 6.8 × 10-8 to 4.6 × 10-7. We compared our findings for 75 congeners with reports in the literature that quantified only 12 congeners. We estimate that these 12 congeners contribute only approximately 4% to the total mass daily intake of polychlorinated naphthalenes and 70% to the total toxic equivalent quantity, indicating underestimation of dietary exposure. The contributions of combustion-associated congeners to the total concentrations of polychlorinated naphthalenes were in the range of 31-52%, suggesting that the ongoing unintentional release of these compounds from industrial thermal processes is an important factor in polychlorinated naphthalene contamination and human exposure in China.

Seasonal and diurnal patterns of outdoor formaldehyde and impacts on indoor environments and health.

Formaldehyde is concerned as an important indoor carcinogen. While contribution of outdoor formaldehyde to indoor concentration is recognized, long-term measurement about its impact on indoor environments remain missing. We measured both outdoor and indoor formaldehyde concentrations for over one year in Nanjing (east-central China) and calculated the outdoor/indoor (O/I) ratios. 64.8% of the measured outdoor concentration have exceeded the chronic reference exposure criteria of 0.009 mg/m3 set by Office of Environmental Health Hazard Assessment (OEHHA). The outdoor concentration was highest in summer with median value of 0.020 mg/m3 and lowest in spring with median value of 0.009 mg/m3. Diurnally, outdoor formaldehyde concentration was highest at noon with median value of 0.013 mg/m3 and lowest at night with median value of 0.01 mg/m3. Health analysis revealed that cancer risk by exposure to this concentration level is 1.6 × 10-4, higher than threshold limit of 10-6. In addition, the median O/I ratios are 0.18 and 0.27 in two offices, indicating that outdoor formaldehyde contributes to indoor concentrations by about one quarter. The change of O/I ratio also shows a similar seasonal and diurnal trend as outdoor concentrations (highest in the summer in a year and at noon in a day). Outdoor formaldehyde concentration is therefore not negligible as a contributor to indoor concentration, especially as indoor concentration limit gets continuously lowered. This factor should be taken into account in indoor air quality design and maintenance.

Behavioral and neural correlates of social network size: The unique and common contributions of face recognition and extraversion.

OBJECTIVES: Humans are inherently social creatures and can gain advantages from larger network size. Researches have shown that different cognitive and personality factors may result in individual differences of social network size (SNS). Here, we focused on whether face recognition ability and extraversion were related to SNS and the neural basis underlying the relations. METHODS: Behaviorally, we adopted the face-inversion task, NEO personality inventory, and computerized SNS test to explore the relationships between face recognition, extraversion, and SNS. Neurally, we used resting state functional magnetic resonance imaging and fractional amplitude of low-frequency fluctuation (fALFF) analysis method to investigate the neural correlates of SNS and then revealed whether face recognition and extraversion were related to SNS relevant brain regions. RESULTS: We found that individuals with better face recognition ability and more extraverted personality had larger size of social network. In addition, we found that SNS was positively associated with the fALFF in the ventromedial prefrontal cortex (vmPFC), right superior temporal sulcus, and precuneus. Interestingly, the fALFF in the vmPFC significantly correlated with face recognition ability. CONCLUSIONS: Our study suggests that both face recognition and extraversion may be important correlates of SNS, and the underlying spontaneous neural substrates are partially dissociable.

Gray matter structures associated with neuroticism: A meta-analysis of whole-brain voxel-based morphometry studies.

Neuroticism is major higher-order personality trait and has been robustly associated with mental and physical health outcomes. Although a growing body of studies have identified neurostructural markers of neuroticism, the results remained highly inconsistent. To characterize robust associations between neuroticism and variations in gray matter (GM) structures, the present meta-analysis investigated the concurrence across voxel-based morphometry (VBM) studies using the anisotropic effect size signed differential mapping (AES-SDM). A total of 13 studies comprising 2,278 healthy subjects (1,275 females, 29.20 ± 14.17 years old) were included. Our analysis revealed that neuroticism was consistently associated with the GM structure of a cluster spanning the bilateral dorsal anterior cingulate cortex and extending to the adjacent medial prefrontal cortex (dACC/mPFC). Meta-regression analyses indicated that the neuroticism-GM associations were not confounded by age and gender. Overall, our study is the first whole-brain meta-analysis exploring the brain structural correlates of neuroticism, and the findings may have implications for the intervention of high-neuroticism individuals, who are at risk of mental disorders, by targeting the dACC/mPFC.

Brain gray matter structures associated with trait impulsivity: A systematic review and voxel-based meta-analysis.

Trait impulsivity is a multifaceted personality characteristic that contributes to maladaptive life outcomes. Although a growing body of neuroimaging studies have investigated the structural correlates of trait impulsivity, the findings remain highly inconsistent and heterogeneous. Herein, we performed a systematic review to depict an integrated delineation of gray matter (GM) substrates of trait impulsivity and a meta-analysis to examine concurrence across previous whole-brain voxel-based morphometry studies. The systematic review summarized the diverse findings in GM morphometry in the past literature, and the quantitative meta-analysis revealed impulsivity-related volumetric GM alterations in prefrontal, temporal, and parietal cortices. In addition, we identified the modulatory effects of age and gender in impulsivity-GM volume associations. The present study advances understanding of brain GM morphometry features underlying trait impulsivity. The findings may have practical implications in the clinical diagnosis of and intervention for impulsivity-related disorders.

Burden and Risk of Polychlorinated Naphthalenes in Chinese Human Milk and a Global Comparison of Human Exposure.

Polychlorinated naphthalenes (PCNs) are carcinogenic contaminants. Residues from historical production and ongoing unintentional releases from industrial thermal sources have led to the ubiquitous presence of PCNs in the environment. Our previous study has revealed that unintentional releases may be the main sources of PCNs in human milk from China. However, an assessment of PCN burden in human milk and exposure differences between historical residues and unintentional release exposure has not been conducted. In this study, we performed the first comparison of human exposure to PCNs and evaluated the differences between the estimated health risks from historical residues and unintentional releases. Three characteristic PCN congener patterns found in Chinese human milk specimens collected from 100 cities/counties can be considered characteristic of PCN exposures in regions with unintentional industrial releases as the main PCN sources. The health risk assessment suggested potential noncarcinogenic health effects in infants aged 0-6 months. The hazard index calculated for infants in Sweden indicates a strong impact of historical residues that nonetheless decreases over time, and a comparison of the hazard indices calculated for China and Ireland suggests that ongoing unintentional formation and release of PCNs from industrial processes should be a matter of public health concern.

Rapid determination of 13 organophosphorus flame retardants in milk by using modified quick, easy, cheap, effective, rugged, and safe technique, solid-phase extraction, and HPLC-MS/MS.

Organophosphorus flame retardants are a class of widely used plasticizers and flame retardants. In this study, an analytical methodology for the simultaneous determination of 13 organophosphorus flame retardants in milk was developed by using high-performance liquid chromatography-tandem mass spectrometry in combination with a modified quick, easy, cheap, effective, rugged, and safe technique and solid-phase extraction. The experimental parameters of the sample purification procedure and high-performance liquid chromatography-tandem mass spectrometry were optimized. The developed method was validated in terms of linearity, limits of detection, recovery, and precision. The method showed a linear response in the 1-100 ng/mL concentration range and the limits of detection ranged from 0.001 to 0.3 ng/mL. The mean recoveries for most organophosphorus flame retardants were in the ranges of 75.0-115.8% (spiked at 2.5 ng/mL) and 76.7-124.8% (spiked at 25 ng/mL), with relative standard deviations of <13.09%. The developed methodology was successfully applied to the analysis of nine human milk samples and nine commercial cow milk samples. Eleven organophosphorus flame retardants were detected in the human milk samples, with median concentrations that ranged from lower than the limit of detection to 1.47 ng/mL, and only nine organophosphorus flame retardants were detected in cow milk samples, with median levels of <0.32 ng/mL.