Photoaged Nanopolystyrene Affects Neurotransmission to Induce Transgenerational Neurotoxicity in Caenorhabditis elegans.

Nanopolystyrene (NPS), a frequently employed nanoplastic, is an emerging environmental contaminant known to cause neurotoxicity in various organisms. However, the potential for transgenerational neurotoxic effects, especially from photoaged NPS (P-NPS), remains underexplored. This study investigated the aging of virgin NPS (V-NPS) under a xenon lamp to simulate natural sunlight exposure, which altered the physicochemical characteristics of the NPS. The parental generation (P0) of Caenorhabditis elegans was exposed to environmental concentrations (0.1-100 µg/L) of V-NPS and P-NPS, with subsequent offspring (F1-F4 generations) cultured under NPS-free conditions. Exposure to 100 µg/L P-NPS resulted in more pronounced deterioration in locomotion behavior in the P0 generation compared to V-NPS; this deterioration persisted into the F1-F2 generations but returned to normal in the F3-F4 generations. Additionally, maternal exposure to P-NPS damaged dopaminergic, glutamatergic, and serotonergic neurons in subsequent generations. Correspondingly, there was a significant decrease in the levels of dopamine, glutamate, and serotonin, associated with reduced expression of neurotransmission-related genes dat-1, eat-4, and tph-1 in the P0 and F1-F2 generations. Further analysis showed that the effects of P-NPS on locomotion behavior were absent in subsequent generations of eat-4(ad572), tph-1(mg280), and dat-1(ok157) mutants, highlighting the pivotal roles of these genes in mediating P-NPS-induced transgenerational neurotoxicity. These findings emphasize the crucial role of neurotransmission in the transgenerational effects of P-NPS on locomotion behavior, providing new insights into the environmental risks associated with exposure to photoaged nanoplastics.

Chronic neurotoxicity of Tetrabromobisphenol A: Induction of oxidative stress and damage to neurons in Caenorhabditis elegans.

Tetrachlorobisphenol A (TCBPA) has been used as an alternative flame retardant in various fields. However, the long-term effects of TCBPA on the nervous system remain unclear. Thus, Caenorhabditis elegans (L4 larvae) were selected as a model animal to investigate the neurotoxic effects and underlying mechanisms after 10 d of TCBPA exposure. Exposure to TCBPA (0.01-100 µg/L) decreased locomotive behavior in a concentration-dependent manner. In addition, reactive oxygen species (ROS) formation and lipofuscin accumulation were significantly increased, and the expression of sod-3 was upregulated in the exposed nematodes, indicating that TCBPA exposure induced oxidative damage. Furthermore, 100 µg/L TCBPA exposure caused a reduction in dopamine and serotonin levels, and damage in dopaminergic and serotoninergic neurons, which was further confirmed by the downregulated expression of related genes (e.g., dop-1, dop-3, cat-1, and mod-1). Molecular docking analysis demonstrated the potential of TCBPA to bind to the neurotransmitter receptor proteins DOP-1, DOP-3, and MOD-1. These results indicate that chronic exposure to TCBPA induces neurotoxic effects on locomotive behavior, which is associated with oxidative stress and damage to dopaminergic and serotoninergic neurons.

Photoaged microplastics induce neurotoxicity associated with damage to serotonergic, glutamatergic, dopaminergic, and GABAergic neuronal systems in Caenorhabditis elegans.

Microplastics (MPs) are ubiquitous environmental contaminants that cause neurotoxicity in various organisms. MPs are typically affected by light irradiation and undergo photoaging. However, the neurotoxic effects of photoaged polystyrene (P-PS) and its underlying mechanisms remain unclear. In this study, locomotion behaviors, neuronal development, neurotransmitter levels, and the expression of neurotransmission-related genes were investigated in Caenorhabditis elegans exposed to P-PS at environment-relevant concentrations (0.1-100 µg/L). The characterization results showed that photoaging accelerated the aging process and changed the physicochemical properties of the MPs. The toxicity results suggested that exposure to 1-100 µg/L P-PS caused more severe neurotoxicity than virgin polystyrene (V-PS) with endpoints of head thrashes, body bends, wavelength, and mean amplitude. Exposure to P-PS also altered the fluorescence intensity and neurodegeneration percentage of serotonergic, glutamatergic, dopaminergic, and aminobutyric acid (GABA) in transgenic nematodes. Similarly, significant reductions in the levels of these neurotransmitters were also observed. Based on Pearson's correlation, locomotion behaviors were negatively correlated with the neurotransmission of serotonin, glutamate, dopamine, and GABA. Further investigation suggested that the expression of neurotransmitter-related genes (e.g., tph-1, eat-4, and unc-46) was significantly altered in the nematodes. Collectively, the neurotoxic effects of P-PS were attributed to abnormal neurotransmission. This study highlights the potential toxicity of MPs photoaged under environmentally relevant conditions.

Carboxyl-modified polystyrene microplastics induces neurotoxicity by affecting dopamine, glutamate, serotonin, and GABA neurotransmission in Caenorhabditis elegans.

Microplastics (MPs) are ubiquitous in various environmental media and have potential toxicity. However, the neurotoxicity of carboxyl-modified polystyrene microplastics (PS-COOH) and their mechanisms remain unclear. In this study, Caenorhabditis elegans was used as a model to examine the neurotoxicity of polystyrene microplastic (PS) and PS-COOH concentrations ranging from 0.1 to 100 µg/L. Locomotion behavior, neuron development, neurotransmitter level, and neurotransmitter-related gene expression were selected as assessment endpoints. Exposure to low concentrations (1 µg/L) of PS-COOH caused more severe neurotoxicity than exposure to pristine PS. In transgenic nematodes, exposure to PS-COOH at 10-100 µg/L significantly increased the fluorescence intensity of dopaminergic, glutamatergic, serotonergic, and aminobutyric acid (GABA)ergic neurons compared to that of the control. Further studies showed that exposure to 100 µg/L PS-COOH can significantly affect the levels of glutamate, serotonin, dopamine, and GABA in nematodes. Likewise, in the present study, the expression of genes involved in neurotransmission was altered in worms. These results suggest that PS-COOH exerts neurotoxicity by affecting neurotransmission of dopamine, glutamate, serotonin, and GABA. This study provides new insights into the underlying mechanisms and potential risks associated with PS-COOH.

The socioeconomic and lifestyle determinants of contraceptive use among Chinese college students: a cross-sectional study.

BACKGROUND: Chinese youth have become more sexually active over the years, yet their behaviours of contraceptive use are influenced by socioeconomic and lifestyle factors. This study aimed to investigate the socioeconomic and lifestyle determinants of contraceptive use among Chinese college students, and to investigate quantitatively their reasons for choosing different contraceptive methods. METHODS: The study used the data from a cross-sectional survey, which was conducted in 2015 among 17,517 students from 130 colleges and professional schools in mainland China. Chi-square tests were performed to test the differences in the awareness and uses of contraceptives between male and female students. Multivariable logistic regression models were used to analyse the associations between socioeconomic and lifestyle factors and contraceptive uses. RESULTS: Condoms (95%), oral contraceptives (91%) and emergency contraceptives (71%) were the most commonly known contraceptive methods among the sample of Chinese youth that were surveyed. Among male participants, high monthly expenditure (OR = 1.37, 95%CI: 1.07-1.75), light alcohol consumption (OR = 1.47, 95%CI: 1.03-2.11), and high sexual knowledge (OR = 1.96, 95%CI: 1.57-2.45) were positively associated with contraceptive uses, while tobacco use (OR = 0.47, 95%CI: 0.23-0.95) showed a negative association with contraceptive uses. Among female students, suburban residency (OR = 1.38, 95%CI: 1.03-1.83), high level of parental education (OR = 1.96, 95%CI: 1.19-3.22), moderate alcohol consumption (OR = 2.66, 95%CI: 1.05-6.77), and high sexual knowledge (OR = 1.50, 95%CI: 1.18-1.91) were positively associated with contraceptive uses, while tobacco use (OR = 0.60, 95%CI: 0.36-0.99) showed a negative association. CONCLUSIONS: A series of socioeconomic and lifestyle factors were associated with contraceptive choices among Chinese college students. Targeted sexual education programs are in demand to improve the awareness and the use of contraceptives in this population.

Self-identified sexual orientations and high-risk sexual behaviours among Chinese youth.

PURPOSE: High-risk sexual behaviour is a factor affecting the health of sexual minority students, yet few related studies have been completed among Chinese students. This article explores the distribution of sexual minority groups and its association with high-risk sexual behaviours and symptoms of sexually transmitted infections(STIs) among Chinese college students. METHODS: An internet-based questionnaire was applied, and a sample of 17 966 surveys from 130 Chinese colleges was collected. Based on their self-reports, participants were classified into the following groups: homosexual male or female, heterosexual, bisexual, and sexual orientation unknown. High-risk sexual behaviours were defined as having sexual intercourse before the age of 18 years, having one's sexual debut with a non-regular partner, having had more than four sexual partners before investigation, and having mostly had sexual intercourse without using condoms. Logistic regression models were constructed to analyse the associations. RESULTS: The proportions of the homosexual males and females, and the bisexual groups were 1.62%, 0.88% and 5.07%, respectively. Homosexual males were more likely to have their sexual debut with a non-regular partner (OR 4.79, 95% CI 3.38 to 6.78), having more than four sexual partners (OR 5.81, 95% CI 4.06 to 8.32), having their sexual debut before the age of 18 years (OR 1.92, 95% CI 1.34 to 2.76), and not using condoms for most episodes of sexual intercourse (OR 1.47, 95% CI 1.00 to 2.17). Similar associations also existed among homosexual females. A positive association between sexual orientation and having symptoms of STIs (OR 1.49, 95% CI 1.02 to 2.18) was found among homosexual males. CONCLUSIONS: Sexual minority groups among Chinese college students had a greater risk of engaging in high-risk sexual behaviours and having STI symptoms. Future studies and interventions should focus on this population.

The association between work related factors and breastfeeding practices among Chinese working mothers: a mixed-method approach.

Background: Breastfeeding rates remain low in China and some mothers stop breastfeeding shortly after returning to work. Our study aimed to investigate the association between breastfeeding practices of working mothers and their employment status (formal versus informal) and occupational fields (agriculture related, industry related, and business and white collar). We also identified key work-related factors that influence breastfeeding practices in Chinese working mothers. Methods: This is a mixed-method research consisted of two components. We conducted a cross-sectional study of 10,408 breastfeeding mothers with children under 12 months old from 12 regions in China from July 2017 to January 2018. Multiple logistic regression was used to calculate adjusted odds ratios (AdjORs) and 95% confidence intervals (CIs) for breastfeeding practices. For the qualitative component, semi-structured interviews were conducted with 84 breastfeeding mothers in the study areas from July to December 2017, Content analysis was used for the qualitative component. Results: Agriculture related occupations were positively associated with early initiation of breastfeeding (AdjOR 1.32, 95% CI 1.15, 1.51), current breastfeeding (AdjOR 1.76, 95% CI 1.41, 2.20), ever breastfed (AdjOR 1.69, 95% CI 1.09, 2.62), exclusive breastfeeding (AdjOR 1.30, 95% CI: 1.04, 1.62), and predominant breastfeeding (AdjOR 1.72, 95% CI 1.44, 2.05). Business and white collar occupations were positively associated with early initiation (AdjOR1.38, 95% CI 1.23, 1.56) and ever breastfed (AdjOR 1.64, 95% CI 1.12, 2.39), and inversely associated with predominant breastfeeding (AdjOR 0.81, 95% CI 0.68, 0.95). For industry related and business and white collar occupations, informal employment was negatively related to current breastfeeding. In qualitative analysis, four main themes were developed to identify key work-related factors that influence breastfeeding practices: 1) employment benefits; 2) commute time; 3) workplace environment; 4) labor intensity. Mothers who experienced difficulties in one or more of the above would choose to lower breastfeeding frequency or stop breastfeeding. Conclusions: Having flexible work schedules and proximity of workplace to home can assist continuance of breastfeeding. Policies promoting supportive breastfeeding environment at work ought to be implemented. Additionally, informally employed mothers require more attention due to limited legal protection.

Breastfeeding duration of different age groups and its associated factors among Chinese women: a cross-sectional study.

Background: The current situation of breastfeeding in China has been discussed in many articles, and a declining trend of breastfeeding duration has been confirmed. The associations between various socioeconomic, reproductive factors and breastfeeding duration have been discussed as well. However, there remains a lack of evidence on breastfeeding duration amongst different age groups. Methods: Data was extracted from the baseline of a large cohort study: a sample of 300,000 adult women born in the 1930s' through 1970s' from 10 geographically distinct regions was obtained. The breastfeeding duration was assumed by breastfeeding duration of the first child. Different age groups were categorized by 10-year age groups, and they were born in 1930-1938, 1939-1948, 1949-1958, 1959-1968, and 1969-1974. Multivariable linear regression was used to evaluate the associations between breastfeeding duration and sociodemographic, and reproductive factors (i.e.: different age groups, education, household size, use of oral contraceptive pills, age at menarche, and age at first birth). Results: The mean breastfeeding duration (Standard Deviation) of women born in 1930-1938, 1939-1948, 1949-1958, 1959-1968, and 1969-1974 were 15.4 (9.2), 14.8 (8.2), 14.7 (8.9), 12.8 (7.2), 13.1 (7.2) months, respectively. Younger age groups, higher levels of education, and use of oral contraceptive pills were negatively associated with breastfeeding duration. In particular, the negative association with higher levels of education (for urban regions: ßmiddle school = - 1.3, ßhigh school & above = - 1.6; for rural regions: ßmiddle school = - 0.6, ßhigh school & above = - 1.2; all p < 0.0001) was found significant in both rural and urban areas, household size (ß = - 0.1, p < 0.0001) and age at first birth (ß = - 0.2, p < 0.0001) were negatively associated with breastfeeding duration only in urban areas, but were all positively associated with breastfeeding duration in rural areas. Conclusions: This research demonstrated that, among Chinese women, younger age groups and higher levels of education were negatively associated with breastfeeding duration. Considering the declining trend of breastfeeding duration in China, healthcare providers need to continue advocating for breastfeeding practices. We also call for collaboration with various sectors and concerned groups to actions that promote breastfeeding-friendly environment and measures.

Recruitment and significance of Th22 cells and Th17 cells in malignant ascites.

T helper (Th)22 and Th17 cells are implicated in the pathogenesis of a number of types of cancer. However, the function of Th22 and Th17 cells in malignant ascites (MA) remains unknown. The present study aimed at examining the distribution, phenotypes, recruitment, and prognostic value of Th22 and Th17 cells in MA from patients with hepatocellular carcinoma (HCC). A total of 26 patients with HCC with MA and 15 healthy controls were included in the present study. The proportion of Th22 cells, Th17 cells, C-C motif chemokine receptor (CCR)4, CCR6 and CCR10 were examined using flow cytometry. Interleukin (IL-)22, IL-17, C-C motif chemokine ligand (CCL)20, CCL22 and CCL27 were investigated using ELISA. In addition, the chemoattractant activity of chemokines for Th22 and Th17 cells in vitro were examined via a chemotaxis assay. The results of the present study demonstrated that Th22 cells, Th17 cells, IL-22 and IL-17 were significantly increased in MA compared with the corresponding blood and peripheral blood from healthy controls. Additionally, Th22 cells expressed increased concentrations of CCR6, CCR4 and CCR10, and Th17 cells expressed increased concentrations of CCR4 and CCR6 in MA compared with the corresponding blood. The chemotaxis assay revealed that CCL20/CCR6, CCL22/CCR4 and CCL27/CCR10 were responsible for the recruitment of Th22 cells into MA, whereas CCL22/CCR4 was responsible for the recruitment of Th17 cells. Furthermore, the patients with an increased number of Th17 cells exhibited an increased survival time compared with patients with a limited number of Th17 cells. Th22 and Th17 cells serve an important function in the development of MA, and the accumulation of Th22 and Th17 cells in MA may be due to a local increase in proinflammatory cytokines and chemokines. Increased Th17 cell numbers in MA may indicate the improvement of patient survival.

Childhood sexual abuse, risky sexual behaviors and adverse reproductive health outcomes among Chinese college students.

BACKGROUND: Childhood sexual abuse (CSA) is a serious public health problem worldwide. OBJECTIVES: We reported the prevalence of CSA and examined its association with risky sexual behaviors and adverse reproductive health outcomes among college students in China. PARTICIPANTS AND SETTING: Participants were 17,966 college students from 130 colleges in Eastern, Central, and Western China, who completed the online questionnaire in January-August 2015. METHODS: Data were obtained from a cluster-random Internet-based survey. Multivariate logistic regression analyses were employed: risky sexual behaviors and adverse reproductive health outcomes were outcome variables, and various types of CSA were predictor variables, while adjusting for socio-demographic and lifestyle characteristics. RESULTS: The overall prevalence of any type of CSA was 27.5%. Most perpetrators were friends/acquaintances (34.6%) or intimate partners (24.7%) of the victims. Respondents who reported penetrative CSA were strongly associated with regular unprotected sex (odds ratio (OR): 3.0, 95% confidence interval (CI): 2.2-4.0), early sexual debut (OR: 5.5, 95% CI: 3.3-9.1), having genital tract symptoms in the last 12 months (OR: 5.0, 95% CI: 4.1-6.0), unintended pregnancy (OR: 6.2, 95% CI: 4.2-9.0), and induced abortion (OR: 5.5, 95% CI: 3.7-8.2) (for boys, the survey asked about history of unintended pregnancy and induced abortion of their sexual partners). A dose-response relationship was found across non-contact, contact, and penetrative CSA. CONCLUSIONS: CSA experience may increase the likelihood of risky sexual behaviors and adverse reproductive health outcomes in victims' early adulthood.

Real-Time Tumor Gene Expression Profiling to Direct Gastric Cancer Chemotherapy: Proof-of-Concept "3G" Trial.

Purpose: The oxaliplatin plus S-1 and cisplatin plus S-1 regimens are interchangeably used in the management of advanced gastric cancer. The previously reported G-intestinal (G1) and G-diffuse (G2) intrinsic gene expression signatures showed promise for stratifying patients according to their tumor sensitivity to oxaliplatin or cisplatin.Experimental Design: The proof-of-concept, multicenter, open-label phase II "3G" trial was done to prospectively evaluate the feasibility and efficacy of using genomic classifiers to tailor treatment in gastric cancer. Patients' tumors were classified as "G1" or "G2" using a nearest-prediction template method, or "G3" (unclear assignment) when FDR ≥ 0.05. The first 30 patients in the "G1" cohort were assigned oxaliplatin plus S-1 (SOX) chemotherapy; thereafter, subsequently recruited "G1" patients were treated with cisplatin plus S-1 (SP) chemotherapy. "G2" patients and "G3" patients were treated with SP and SOX chemotherapy, respectively.Results: A total of 48, 21, and 12 patients, respectively, were given "G1," "G2," and "G3" genomic assignments. Median turnaround time was 7 days (IQR, 5-9). Response rates were 44.8%, 8.3%, 26.7%, and 55.6% for the "G1-SOX," "G1-SP," "G2," "G3" cohorts, respectively; and was higher in G1 patients treated with SOX compared with SP (P = 0.033). Exploratory analyses using the genomic classifier of Lei and colleagues validated the utility of the metabolic signature as a biomarker for predicting benefit from chemotherapy (log-rank P = 0.004 for PFS), whereas the Asian Cancer Research Group classifier did not demonstrate any predictive value.Conclusions: This bench-to-bedside effort establishes a reasonable turnaround time for gene expression profiling and possible utility of genomic classifiers in gastric cancer treatment stratification. Clin Cancer Res; 24(21); 5272-81. ©2018 AACR.