International Journal of Environmental Health Research最新文献

Salmonella typhimurium is a Gram-negative bacterium that causes salmonellosis. It has been reported that this bacterium can infect immune system cells and spread throughout the body. This infection process can be influenced by pesticide exposure, and this phenomenon may also cause alterations in cell death. This could be beneficial for the bacterium, as it allows it to infect other cells, evade the immune system, and acquire nutrients. In this study, apoptosis and necrosis were evaluated in human mononuclear cells previously exposed to diazoxon (DXN) (1 µM) and infected with S. typhimurium for 1 h. It was observed that in mononuclear cells exposed only to the pesticide or infected with the bacteria, cell death occurred mainly through apoptosis. However, the combination of both factors led to necrosis. Suggesting Mononuclear that the pesticide enabled the activation of other signaling mechanisms. Additionally, actin polymerization activity increases when cells are exposed to bacteria and pesticides, suggesting the activation of mechanisms related to the actin cytoskeleton. Conversely, when colonies exposed to both DXN and S. typhimurium harbored more intracellular bacteria. These findings suggest that diazoxon exposure combined with S. typhimurium infection induces an immunotoxic process in which the predominant mechanism is necrosis.

This study presents a four-year analysis of cardiopulmonary hospital admissions related to PM_2.5 exposure in Bangkok to assess the short-term effects of air pollution on health. The Monte Carlo simulation-based AirQ+ model was employed to estimate hospital admissions attributable to various PM_2.5 concentrations. The average PM_2.5 concentration was 40 ± 17 µg/m³. The monthly median contribution of PM_2.5 to total particulate matter pollution ranged from 0.40 to 0.60. Individuals were exposed to PM_2.5 levels classified as "unhealthy for sensitive groups" (36-56 µg/m³) or "unhealthy for all" (57-150 µg/m³) on approximately 50% days annually). Cardiopulmonary admissions peaked during the winter, with 5,755 to 7,000 respiratory cases and approximately 7,000 cardiovascular cases, while both conditions were least prevalent in the summer (respiratory: 4,000; cardiovascular: 5,300). The PM_2.5 concentrations mirrored this seasonal pattern, reaching approximately 50 µg/m³ in winter and decreasing to approximately 25 µg/m³ in summer. The AirQ+ simulation estimated that PM_2.5 exposure exceeding 15 µg/m³ was associated with 3,306 (95% CI: 0 -15,841) additional respiratory cases and 1,497 (95% CI: 701-6,723) additional cardiovascular cases. Conversely, a 5 µg/m³ reduction in PM2.5 levels could lead to a 22% decrease in hospital admissions for cardiopulmonary diseases, whereas a 5 µg/m³ increase could result in a 16% increase in hospitalizations.

Alkylphenols (APs) and their ethoxylates (APEs) are endocrine disruptors found in aquatic environments. This study evaluated the neurotoxic effects of bisphenol A (BPA), 4-nonylphenol (4-NP), and 3-tert-butylphenol (tertBP) in wild Mezquital silverside (Chirostoma jordani) from Lake Zumpango across dry, rainy, and cold-dry seasons. Biomarkers analyzed included acetylcholinesterase (AChE), carboxylesterase (CbE), butyrylcholinesterase (BChE), and γ-aminobutyric acid (GABA) levels in brain and spinal cord. Results showed seasonal and tissue-specific differences in enzymatic activities correlating with AP and APE concentrations. BChE and CbE activities were elevated during the dry season, associated with higher 4-NP sediment levels and lower BPA and tertBP in water. AChE activity and GABA levels peaked in the rainy season when tertBP was absent. Total phenols fluctuated seasonally but showed no clear neurotoxic association. These findings provide initial evidence of neurotoxic disruption in wild Mezquital silverside by BPA, 4-NP, and tertBP, warranting further ecotoxicological investigation.

A cross-sectional study involving 239 teachers from 44 public secondary schools was conducted using an online questionnaire. Most teachers (95%) had never received training on exposure to chalk particles, and 76% did not take precautionary measures. Teachers opened windows (20%), frequently washed their hands (16%), and opened doors (15%) to reduce exposure. Despite the lack of training, most teachers (88%) recognised that exposure to chalk particles poses health risks. Most teachers (51%) knew that exposure to chalk particles could occur through inhalation, ingestion, and dermal routes. Chi-squared results indicated no significant differences (p > 0.05) in teachers' age, sex, and work experience regarding their knowledge of exposure to chalk particles. A work experience of 25-30 years was linked to knowledge (AOR: 1.04, CI: 0.27-4.17, p < 0.05). Coughing (19%), throat discomfort (16%), nasal congestion (11%), and headaches (10%) were the most prevalent health symptoms. Work experience of 5-10 (AOR: 3.58, CI: 1.64-8.27, p < 0.05), 15-20 (AOR: 4.76, CI: 1.77-15.25, p < 0.05), and 25-30 (AOR: 3.69, CI: 1.23-13.77, p = 0.03) years was associated with experiencing health symptoms. Due to a lack of training and awareness, teachers unknowingly implemented measures to reduce exposure to chalk particles.

Québec's COVID-19 wastewater surveillance program, initiated in March 2022, was evaluated after its first year to determine its effectiveness in tracking SARS-CoV-2 transmission. The evaluation assessed the program's validity, completeness, and timeliness. As per visual analysis, results showed temporal coherence between wastewater and clinical data, although this was period dependent. Cross-correlation function analysis failed to generate consistent results and interpretable patterns between wastewater signal and clinical indicators. The percentage of unplanned missing wastewater results was minimal (ranging from 1% to 21%, with a median of 3%). Planned missing data caused by different sampling regimen required adaptation in data processing and interpretation. The median time between infection and wastewater data availability was 13.1 days, compared to 8 days for clinical data, although high variability in delays was seen between sampling sites. The wastewater data dissemination delay was the main bottleneck to provide timely information to public health authorities. This initial evaluation highlights the program's potential to generate complementary information to clinical data and can help future studies navigate the complexities of wastewater monitoring.

Polyhydroxyalkanoates (PHAs) are biodegradable polymers with immense potential as eco-friendly alternatives to conventional plastics. The study aimed to screen for PHA-producing bacteria in different soil samples and evaluating for their hydrocarbon utilization. In the present study, a total of 30 soil samples were collected from different sites, such as petrol bunk, sewage, and garden. Among the total bacterial isolates obtained, 30 showed positive PHA production by preliminary screening Sudan Black B, Nile blue, and Nile red staining techniques. Quantitative estimation of PHA was performed using a shake flask experiment in a minimal medium with an initial pH of 7, 10% (v/v) inoculum, 30°C, 170 rpm at 72 h. The isolate Bacillus subtilis PHAD13 produced the highest PHA 59% extracted by sodium hypochlorite method. Polymers from Bacillus amyloliquefaciens (PHAD7), Bacillus subtilis (PHAD13), Bacillus cereus (NS1), and Klebsiella sp. (NG5) were characterized by FT-IR analysis. GC-MS analysis revealed the presence of PHA copolymer, with tridecanoic acid (C13:0, MCL-PHA), and longer chain monomers (C15:0-C18:1, LCL-PHA); coexistence indicates heterogeneous monomer integration. The bacterial growth on Bushnell-Haas agar supplemented with spent engine oil demonstrated hydrocarbon tolerance indicating its bioremediation potential. The present study demonstrates the dual functional capability of Bacillus subtilis for bioplastic production and hydrocarbon degradation.

Traditional fuels including firewood, charcoal, or kerosene still remains a primary cooking fuel in rural India and the health impacts of such exposures in relation to T2D are not fully understood. Hence, this study investigates the association between traditional fuel use and prevalence of T2D in rural Tamil Nadu. Data were derived from the TREND study, a population-based cross-sectional survey conducted between 2018 and 2021 across 30 villages in Cheyyur Taluk, Tamil Nadu. A total of 13,877 adults aged ≥18 years with complete information on cooking fuel type and valid Oral Glucose Tolerance Test results were included. Participants were categorized as traditional fuel users (n = 13669) or clean fuel users(n = 208). Higher prevalence of T2D were observed among traditional fuel users (14.2% vs 12%; p < 0.001) and in the households who did not have a separate room for cooking (16.5% vs. 12.2%; p < 0.001) when compared to the clean fuel users and households with separate room for cooking. Traditional fuel use was associated with 80% higher odds of T2D among women (OR = 1.8; p < 0.05), independent of age, sex, family history, BMI, education and income. There is an urgent need for effective and sustained cleaner fuel adoption, improved kitchen ventilation in rural populations of India.

This study reports Rooibos-mediated silver nanoparticles (R-AgNPs) using the aqueous extract of Aspalathus linearis (Rooibos) and evaluates their multifunctional biological activities. The synthesis of R-AgNPs was indicated by a colour change from yellow to brown and a characteristic absorption peak at 432 nm. R-AgNPs were predominantly spherical, EDS confirmed the presence of silver, while XRD revealed a crystalline structure with an average particle size of 13.94 nm. The cytotoxic potential of R-AgNPs was assessed in SK-MEL-30 and L929 cells. Dose-dependent decreases in cell viability were observed, with respective IC₅₀ values of 17.32µg/mL and 30.07 µg/mL. Wound healing assays revealed that a dose of 6.25 µg/mL significantly increased fibroblast migration, resulting a 60.5-fold increase in wound closure at 24 hours, compared to a 22.6-fold in the control group. At 12 hours, R-AgNPs had accelerated cell migration by around fourfold. R-AgNPs increased TAS and reduced TOS and OSI in SK-MEL-30 cells, while maintaining near-normal oxidative balance in L929 cells. R-AgNPs exhibited concentration-dependent DPPH radical scavenging activity (25.87-65.91%) and strong α-glucosidase inhibition (31.86-100%), indicating their potential as antioxidants and antidiabetics. In conclusion, R-AgNPs exhibit selective cytotoxicity, antioxidant capacity, wound-healing promotion, and antidiabetic activity, highlighting their potential as safe, multifunctional nanotherapeutics for biomedical use.

Padina pavonica and Dictyopteris polypodioides are two widely distributed brown seaweeds whose pharmacological applications remain underestimated. In the present study, ethanolic extracts of P. pavonica and D. polypodioides were tested for cytotoxic activity against MCF-7 (human breast adenocarcinoma), Caco-2 (human colon adenocarcinoma), and HepG2 (human hepatoma) cells. Both seaweeds displayed significant cytotoxic activity against tumoral cells, with D. polypodioides being more effective than P. pavonica. Composition of volatile metabolites in P. pavonica and D. polypodioides was characterized by headspace gas chromatography-mass spectrometry (GC-MS). A total of 35 different volatile metabolites were identified in the two seaweed species. Considering that numerous human pathologies including cancer involve the participation of carbonic anhydrase activity, these compounds were screened as potential inhibitors of human carbonic anhydrase using molecular docking simulation. The results showed that p-acetaminobenzaldehyde and methyl 9(Z)-octadecenoate from P. pavonica, and 6-hydroxynicotinic acid, methyl 7-nonynoate, and methyl (7E)-hexadecenoate from D. polypodioides have high fitness scores, and they, therefore, are promising candidates for prospective pharmacological research.

Per- and polyfluoroalkyl substances (PFAS) have been implicated in various adverse health effects, but their association with clear cell renal cell carcinoma (ccRCC) - a prevalent and aggressive form of kidney cancer often diagnosed at advanced stages - remains unclear. This study employs an integrative computational approach combining network toxicology, machine learning-based prognostic modeling, and virtual drug screening to elucidate the potential mechanistic links between PFAS exposure and ccRCC pathogenesis. Network toxicology analysis identified critical intersection genes, while machine learning evaluation of The Cancer Genome Atlas (TCGA) database revealed key prognostic biomarkers. Furthermore, virtual screening identified several promising therapeutic candidates, including Ecteinascidin, Avodart, and Nilotinib, which demonstrated high binding affinity to pivotal molecular targets such as AIM2, HK3, ATP1A1, and ZAP70. Our findings suggest a potential link/role of PFAS in ccRCC development via dysregulation of specific gene pathways, and the identified compounds could serve as potential therapeutic agents. This study provides novel insights into the carcinogenic mechanisms of PFAS in ccRCC and proposes new avenues for targeted therapy. However, further experimental and clinical validation is necessary to confirm these findings and translate them into improved patient outcomes, while also addressing broader environmental health concerns related to PFAS exposure.