PM2.5-induced iron homeostasis imbalance triggers cardiac hypertrophy through ferroptosis in a selective autophagy crosstalk manner

Exposure to PM2.5 is correlated with cardiac remodeling, of which cardiac hypertrophy is one of the main clinical manifestations. Ferroptosis plays an important role in cardiac hypertrophy. However, the potential mechanism of PM2.5-induced cardiac hypertrophy through ferroptosis remains unclear. This study aimed to explore the molecular mechanism of cardiac hypertrophy caused by PM2.5 and the intervention role of MitoQ involved in this process. The results showed that PM2.5 could induce cardiac hypertrophy and dysfunction in mice. Meanwhile, the characteristics of ferroptosis were observed, such as iron homeostasis imbalance, lipid peroxidation, mitochondrial damage and abnormal expression of key molecules. MitoQ treatment could effectively mitigate these alternations. After treating human cardiomyocyte AC16 with PM2.5, ferroptosis activator (Erastin) and inhibitor (Fer-1), it was found that PM2.5 could promote ferritinophagy and lead to lipid peroxidation, mitochondrial dysfunction as well as the accumulation of intracellular and mitochondrial labile iron. Subsequently, mitophagy was activated and provided an additional source of labile iron, enhancing the sensitivity of AC16 cells to ferroptosis. Furthermore, Fer-1 alleviated PM2.5-induced cytotoxicity and iron overload in the cytoplasm and mitochondria of AC16 cells. It was worth noting that during the process of PM2.5 caused ferroptosis, abnormal iron metabolism mediated the activation of ferritinophagy and mitophagy in a temporal order. In addition, NCOA4 knockdown reversed the iron homeostasis imbalance and lipid peroxidation caused by PM2.5, thereby alleviating ferroptosis. In summary, our study found that iron homeostasis imbalance-mediated the crosstalk of ferritinophagy and mitophagy played an important role in PM2.5-induced ferroptosis and cardiac hypertrophy.

New insight into air pollution-related cardiovascular disease: an adverse outcome pathway framework of PM2.5-associated vascular calcification

Despite the air quality has been generally improved in recent years, ambient fine particulate matter (PM2.5), a major contributor to air pollution, remains one of the major threats to public health. Vascular calcification is a systematic pathology associated with an increased risk of cardiovascular disease. Although the epidemiological evidence has uncovered the association between PM2.5 exposure and vascular calcification, little is known about the underlying mechanisms. The adverse outcome pathway (AOP) concept offers a comprehensive interpretation of all of the findings obtained by toxicological and epidemiological studies. In this review, reactive oxygen species (ROS) generation was identified as the molecular initiating event (MIE), which targeted subsequent key events (KE) such as oxidative stress, inflammation, endoplasmic reticulum (ER) stress, and autophagy, from the cellular to the tissue/organ level. These KEs eventually led to the adverse outcome (AO), namely increased incidence of vascular calcification and atherosclerosis morbidity. To the best of our knowledge, this is the first AOP framework devoted to PM2.5-associated vascular calcification, which benefits future investigations by identifying current limitations and latent biomarkers.

Intelligently Quantifying the Entire Irregular Dental Structure

Quantitative analysis of irregular anatomical structures is crucial in oral medicine, but clinicians often typically measure only several representative indicators within the structure as references. Deep learning semantic segmentation offers the potential for entire quantitative analysis. However, challenges persist, including segmentation difficulties due to unclear boundaries and acquiring measurement landmarks for clinical needs in entire quantitative analysis. Taking the palatal alveolar bone as an example, we proposed an artificial intelligence measurement tool for the entire quantitative analysis of irregular dental structures. To expand the applicability, we have included lightweight networks with fewer parameters and lower computational demands. Our approach finally used the lightweight model LU-Net, addressing segmentation challenges caused by unclear boundaries through a compensation module. Additional enamel segmentation was conducted to establish a measurement coordinate system. Ultimately, we presented the entire quantitative information within the structure in a manner that meets clinical needs. The tool achieved excellent segmentation results, manifested by high Dice coefficients (0.934 and 0.949), intersection over union (0.888 and 0.907), and area under the curve (0.943 and 0.949) for palatal alveolar bone and enamel in the test set. In subsequent measurements, the tool visualizes the quantitative information within the target structure by scatter plots. When comparing the measurements against representative indicators, the tool's measurement results show no statistically significant difference from the ground truth, with small mean absolute error, root mean squared error, and errors interval. Bland-Altman plots and intraclass correlation coefficients indicate the satisfactory agreement compared with manual measurements. We proposed a novel intelligent approach to address the entire quantitative analysis of irregular image structures in the clinical setting. This contributes to enabling clinicians to swiftly and comprehensively grasp structural features, facilitating the design of more personalized treatment plans for different patients, enhancing clinical efficiency and treatment success rates in turn.

Melatonin ameliorates PM2.5-induced spermatogenesis disorder by preserving H3K9 methylation and SIRT3

There was a link between exposure to PM2.5 and male infertility. Melatonin has beneficial effects on the male reproductive processes. How PM2.5 caused spermatogenesis disturbance and whether melatonin could prevent PM2.5-induced reproductive toxicity have remained unclear. The results showed that PM2.5 could inhibit the Nrf2-mediated antioxidant pathway and distinctly increase the cell apoptosis in testes. Moreover, PM2.5 also perturbed the process of meiosis by modulating meiosis-associated proteins such as γ-H2AX and Stra8. Mechanistically, PM2.5 inhibited G9a-dependent H3K9 methylation and SIRT3-mediated p53 deacetylation, which consistent with decreased sperm count and motility rate in ApoE-/- mice. Further investigation revealed melatonin effectively alleviated PM2.5-induced meiosis inhibition by preserving H3K9 methylation. Melatonin also alleviated PM2.5-induced apoptosis by regulating SIRT3-mediated p53 deacetylation. Overall, our study revealed PM2.5 resulted in spermatogenesis disorder by perturbing meiosis via G9a-dependent H3K9 di-methylation and causing cell apoptosis via SIRT3/p53 deacetylation pathway and provided promising insights into the protective role of melatonin in air pollution associated with male infertility.

Size-dependent toxicity of polystyrene microplastics on the gastrointestinal tract: Oxidative stress related-DNA damage and potential carcinogenicity

Microplastics (MPs) and nanoplastics (NPs) have been generally regarded as emerging pollutants and received worldwide attention in recent years. Water and food consumption are the primary pathways for human exposure to MPs/NPs, thus gastrointestinal tracts may be susceptible to their toxicity. Although the recent report has indicated the presence of MPs/NPs in multiple human organs, little is known about their gastric effects. Therefore, this study focused on the adverse effects of polystyrene microplastics (PS-MPs) on gastric epithelium in vivo and in vitro. Surface-enhanced Raman spectroscopy (SERS) revealed the distribution of PS-MPs was associated with their particle sizes, and predominantly concentrated in gastric tissues. Gastric barrier injury and mitochondrial damage were observed in rats after exposure to PS-MPs. Compared with the larger ones, polystyrene nanoplastics (PS-NPs) more significantly reduced the activity of antioxidant enzymes while enhancing the level of MDA, 8-OhdG and γ-H2AX. Meanwhile, PS-MPs caused upregulation of β-catenin/YAP through redox-dependent regulation of nucleoredoxin (NXN) and dishevelled (Dvl). These findings supported the size-dependent effects of PS-MPs on oxidative stress and DNA damage. Moreover, the redox-dependent activation of the β-catenin/YAP cascade suggested a novel toxic mechanism for PS-MPs and implied the potential carcinogenic effects.

The size-dependent in vivo toxicity of amorphous silica nanoparticles: A systematic review

The extensive application of amorphous silica nanoparticles (aSiNPs) in recent years has resulted in unavoidable human exposure in daily life, thus raising widespread concerns regarding the safety of aSiNPs on human health. The particle size is one of the important characteristics of nanomaterials that could influence their toxicity. For the reason that particles with smaller sizes possess larger surface area, which may lead to higher surface activity and biological reactivity. However, due to the complexity of experimental conditions and biological systems, the relationship between the particle size and the toxic effect of aSiNPs remains unclear. Therefore, this systematic review aims to investigate how particle size influences the toxic effect of aSiNPs in vivo and to analyze the relevant experimental factors affecting the size-dependent toxicity of aSiNPs in vivo. We found that 83.8% of 35 papers included in the present review came to the conclusion that smaller-sized aSiNPs exhibited stronger toxicity, though a few papers (6 papers) put forward different opinions. The reasons for smaller aSiNPs manifested greater toxicity were summarized. In addition, certain important experimental factors could influence the size-dependent effects and in vivo toxicity of aSiNPs, such as the synthesis method of aSiNPs, disperse medium of aSiNPs, administration route of aSiNPs, species or strain of experimental animals, sex of experimental animals, aggregation/agglomeration and protein corona of aSiNPs.

Associations of long-term particulate matter exposure with cardiometabolic diseases: A systematic review and meta-analysis

BACKGROUND

This review aimed to establish a holistic perspective of long-term PM exposure and cardiometabolic diseases, identify long-term PM-related cardiovascular and metabolic risk factors, and provide practical significance to preventative measures.

METHOD

A combination of computer and manual retrieval was used to search for keywords in PubMed (2903 records), Embase (2791 records), Web of Science (5488 records) and Cochrane Library (163 records). Finally, a total of 82 articles were considered in this meta-analysis. Stata 13.0 was accustomed to inspecting the studies' heterogeneity and calculating the combined effect value (RR) by selecting the matching models. The subgroup analysis, sensitivity analysis and publication bias tests were also performed.

RESULTS

Meta-analysis figured an association between PM and cardiometabolic diseases. PM2.5 (per 10 μg/m3 increase) boosted the risk of hypertension (RR = 1.14, 95 % CI: 1.09-1.19), coronary heart disease (CHD) (RR = 1.21, 95 % CI: 1.08-1.35), diabetes (RR = 1.16, 95 % CI: 1.11-1.21) and stroke (including ischemic stroke and hemorrhagic stroke). PM10 (per 10 μg/m3 increase) elevated the incidence of hypertension (RR = 1.11, 95 % CI: 1.07-1.16) and diabetes (RR = 1.26, 95 % CI: 1.08-1.47). PM1 (per 10 μg/m3 increase) exposure increased the risk of total dyslipidemia, yielding the RR of 1.10 (95 % CI: 1.01-1.18). Furthermore, the elderly, overweight and higher background pollutant level were potentially susceptible to related diseases.

CONCLUSION

There was a virtual connection between long-term exposure to PM and cardiometabolic diseases. PM2.5 or PM10 (per 10 μg/m3) increased the risk of hypertension, CHD, diabetes, stroke and dyslipidemia, causing cardiovascular "multimorbidity" in high-risk populations.

Prospects and hazards of silica nanoparticles: Biological impacts and implicated mechanisms

With the thrive of nanotechnology, silica nanoparticles (SiNPs) have been extensively adopted in the agriculture, food, cosmetic, and even biomedical industries. Due to the mass production and use, SiNPs inevitably entered the environment, resulting in ecological toxicity and even posing a threat to human health. Although considerable investigations have been conducted to assess the toxicity of SiNPs, the correlation between SiNPs exposure and consequent health risks remains ambiguous. Since the biological impacts of SiNPs can differ from their design and application, the toxicity assessment for SiNPs may be extremely difficult. This review discussed the application of SiNPs in different fields, especially their biomedical use, and documented their potential release pathways into the environment. Meanwhile, the current process of assessing SiNPs-related toxicity on various model organisms and cell lines was also detailed, thus estimating the health threats posed by SiNPs exposure. Finally, the potential toxic mechanisms of SiNPs were also elaborated based on results obtained from both in vivo and in vitro trials. This review generally summarizes the biological effects of SiNPs, which will build up a comprehensive perspective of the application and toxicity of SiNPs.

[Preliminary application of recombinase -aided amplification in detection of Clonorchis sinensis metacercariae in freshwater fish]

OBJECTIVE

To evaluate the performance of recombinase-aided amplification (RAA) assay in detection of Clonorchis sinensis metacercariae in freshwater fish samples, so as to provide insights into standardization and field application of this assay.

METHODS

Wild freshwater fish samples were collected in the rivers of administrative villages where C. sinensis-infected residents lived in Jiangyan District, Xinghua County and Taixing County of Taizhou City, Jiangsu Province from June to September 2022. Genomic DNA was extracted from six freshwater fish specimens (5 g each) containing 0, 1, 2, 4, 8 and 16 C. sinensis metacercariae for fluorescent RAA assay, and the diagnostic sensitivity was evaluated. Fluorescent RAA assay was performed with genomic DNA from C. sinensis, Metorchis orientalis, Haplorchis pumilio and Centrocestus formosanus metacercariae as templates to evaluate its cross-reactions. In addition, the detection of fluorescent RAA assay and direct compression method for C. sinensis metacercariae was compared in field-collected freshwater fish samples.

RESULTS

Positive amplification was found in fresh-water fish specimens containing different numbers of C. sinensis metacercariae, and fluorescent RAA assay was effective to detect one C. sinensis metacercaria in 5 g freshwater fish specimens within 20 min. Fluorescent RAA assay tested negative for DNA from M. orientalis, H. pumilio and C. formosanus metacercariae. Fluorescent RAA assay and direct compression method showed 5.36% (93/1 735) and 2.88% (50/1 735) detection rates for C. sinensis metacercariae in 1 735 field-collected freshwater fish samples, with a statistically significant difference seen (χ2 = 478.150, P < 0.001). There was a significant difference in the detection of C. sinensis metacercariae in different species of freshwater fish by both the direct compression method (χ2 = 11.20, P < 0.05) and fluorescent RAA assay (χ2 = 20.26, P < 0.001), and the detection of C. sinensis metacercariae was higher in Pseudorasbora parva than in other fish species by both the direct compression method and fluorescent RAA assay (both P values < 0.05).

CONCLUSIONS

Fluorescent RAA assay has a high sensitivity for detection of C. sinensis metacercariae in freshwater fish samples, and has no cross-reactions with M. orientalis, H. pumilio or C. formosanus metacercariae. Fluorescent RAA assay shows a higher accuracy for detection of C. sinensis infections in field-collected freshwater fish than the direct compression method.

Associations of multiple air pollutants with kidney function in normal-weight and obese adults and effect modification by free fatty acids

Increasing studies have linked air pollution to kidney dysfunction, however, the associations between the mixture of air pollutants and kidney function and potential effect modifiers remain unclear. We aimed to investigate whether obese adults were more susceptible than normal-weight ones to the joint effects of multiple air pollutants on kidney function and further to explore effect modification by free fatty acids (FFAs). Forty obese and 49 normal-weight adults were recruited from a panel study (252 follow-up visits). Individual exposure levels of air pollutants (PM2.5, PM10, O3, NO2, SO2 and CO) were estimated. Glomerular function (cystatin C (CysC) and estimated glomerular filtration rate (eGFR)) and tubular function (neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1) were evaluated. Plasma levels of FFAs including trans fatty acids (TFAs) and essential fatty acids (EFAs) were quantified using targeted metabolomics. Bayesian kernel machine regression model was applied to estimate the associations between the mixture of air pollutants and kidney function. The results showed significant joint effects of air pollutants on kidney function indicators. In the normal-weight group, the mixture of air pollutants was significantly associated with CysC and eGFRcr-cys when the mixture was at or above its 70 percentile compared with the median, where O3 was identified as the key pollutant. In the obese group, a significantly positive association between the pollutant mixture and NGAL was observed in addition to trends in CysC and eGFRcr-cys, mainly driven by SO2. Interaction analysis suggested that the associations of air pollutants with kidney function were augmented by TFAs in both groups and weakened by EFAs in the normal-weight group. This study highlighted the renal adverse effects of air pollutants and modification of FFAs, which has implications for target prevention for kidney dysfunction associated with air pollution, especially among vulnerable populations.

[Clinical characteristics of children with SARS-CoV-2 Omicron variant infection in Kunming]

Objective: To investigate the clinical characteristics of hospitalized children infected with the Omicron variant in Kunming after the withdrawal of non-pharmaceutical interventions (NPI) and analyze the risk factors of severe cases. Methods: Clinical data was retrospectively collected from 1 145 children with SARS-CoV-2 Omicron infection who were hospitalized in six tertiary grade A hospitals in Kunming from December 10th, 2022 to January 9th, 2023. According to clinical severity, these patients were divided into the general and severe SARS-CoV-2 groups, and their clinical and laboratory data were compared. Between-group comparison was performed using t-test, chi-square test and Mann-Whitney U test. Spearman correlation test and multivariate Logistic regression analysis were used to determine the risk factors of severe illness. Results: A total of 1 145 hospitalized patients were included, of whom 677 were male and 468 female. The age of these patients at visit was 1.7 (0.5, 4.1) years. Specifically, there were 758 patients (66.2%) aged ≤3 years at visit and 387 patients (33.8%) aged >3 years. Of these children, 89 cases (7.8%) had underline diseases and the remaining 1 056 cases (92.2%) had no combined diseases. Additionally, of all the patients, 319 cases (27.9%) were vaccinated with one or two doses of SARS-CoV-2 vaccine, 748 cases (65.3%) had acute upper respiratory tract infection (AURTI), and six cases died (0.5%). A total of 1 051 cases (91.8%) were grouped into general SARS-CoV-2 group and 94 cases (8.2%) were grouped into severe SARS-CoV-2 group. Compared with the general cases, the severe cases showed a lower rate of SARS-CoV-2 vaccination and younger median age, lower lymphocyte count, as well as proportions of CD8+T lymphocyte (36 cases (38.3%) vs. 283 cases (26.9%), 0.5 (2.6, 8.0) vs. 1.6 (0.5, 3.9) years, 1.3 (1.0, 2.7) ×109 vs. 2.7 (1.3,4.4)×109/L, 0.17 (0.12, 0.24) vs. 0.21 (0.15, 0.16), respectively, χ2=4.88, Z=-2.21,-5.03,-2.53, all P<0.05). On the other hand, the length of hospital stay, proportion of underline diseases, ALT, AST, creatine kinase isoenzyme, and troponin T were higher in the severe group compared to those in the general group ((11.6±5.9) vs. (5.3±1.8) d, 41 cases (43.6%) vs. 48 cases (4.6%), 67 (26,120) vs. 20 (15, 32) U/L, 51 (33, 123) vs. 44 (34, 58) U/L、56.9 (23.0, 219.3) vs. 3.6 (1.9, 17.9) U/L, 12.0 (4.9, 56.5) vs. 3.0 (3.0, 7.0) ×10-3 pg/L,respectively, t=-20.43, χ2=183.52, Z=-9.14,-3.12,-6.38,-3.81, all P<0.05). Multivariate regression analysis indicated that increased leukocyte count (OR=1.88, 95%CI 1.18-2.97, P<0.01), CRP (OR=1.18, 95%CI 1.06-1.31, P<0.01), ferritin (OR=1.01, 95%CI 1.00-1.00, P<0.01), interleukin (IL)-6 (OR=1.05, 95%CI 1.01-1.08, P=0.012), D-dimer (OR=2.56, 95%CI 1.44-4.56, P<0.01) and decreased CD4+T lymphocyte (OR=0.84, 95%CI 0.73-0.98, P=0.030) were independently associated with the risk of severe SARS-CoV-2 in hospitalized children with Omicron infection. Conclusions: After the withdrawal of NPI, the pediatric inpatients with Omicron infection in Kunming were predominantly children younger than 3 years of age, and mainly manifested as AURTI with relatively low rate of severe SARS-CoV-2 infection and mortality. Elevated leukocyte counts, CRP, ferritin, IL-6, D-dimer, and decreased CD4+T lymphocytes are significant risk factors for developing severe SARS-CoV-2 infection.

Dosimetric Validation of 3D-Printed Bolus at Different Printing Infill Percentage in VMAT Plan

PURPOSE/OBJECTIVE(S)

The 3D printed bolus technology is rapidly evolving in external beam radiotherapy and printing parameters can have a significant impact on absorbed dose. In this study, a novel 3D printed bolus was designed to evaluate the time and material cost effects, dosimetry differences, and surface dose modulation capabilities in the volumetric-modulated arc therapy (VMAT) plan at different print filling percentages.

MATERIALS/METHODS

A hollow-type bolus, the middle 2.36 mm of 5 mm thickness infilled with different ratio, was designed and printed with polylactic acid (PLA). The ratio of printed material was defined by the infill percentage parameter ranging from 10% to 90%. For each bolus, two treatment plans were designed with AAA algorithm, considering the real computed tomography (CT) scan of the 3D printed bolus and modeling the 3D printed bolus as a virtual bolus structure. Percentage depth dose (PDD) profiles were calculated to build up the mapping equivalent CT value in treatment plan system (TPS). Measurement dose was performed by radiographic films. The PDD profiles were then compared between measured and calculated. A simulation VMAT treatment plan with planning target volume (PTV) close to the body surface was designed on a water-equivalent phantom, and the modulation capabilities of epidermal dose under different filling percentage was compared.

RESULTS

Compared with 100% percent infill 3D printed bolus, The maximum printing time could be reduced by 47.8% and material consumption could be reduced by 42.5%. The surface dose at single field irradiation can reach 69.6% to 85.8% of the maximum dose in different filling boluses. The PDD measurement and mapping equivalent CT calculation deviation was less than 3% when the infill percentage of the middle region is greater than 30%. The dose distribution of the VMAT plan is satisfying for infill percentages greater than 30%.

CONCLUSION

Using the 3D printing technology is possible to modulate the amount of shift of the build-up region by tuning the infill percentage of the 3D printed bolus. Patients could undergo CT simulation without bolus. Appropriate bolus could be selected according to the location of the PTV region and dose requirement.

An Immune-Related Gene Prognostic Prediction Risk Model for Neoadjuvant Chemoradiotherapy in Rectal Cancer Using Artificial Intelligence

PURPOSE/OBJECTIVE(S)

To develop and validate an immune-related gene prognostic model (IRGPM) that can predict disease-free survival (DFS) in patients with locally advanced rectal cancer (LARC) who received neoadjuvant chemoradiotherapy and to clarify the immune characteristics of patients with different prognostic risks.

MATERIALS/METHODS

In this study, we obtained transcriptomic and clinical data from the Gene Expression Omnibus (GEO) database and rectal cancer database of West China Hospital. Genes in the RNA immune-oncology panel were extracted. Elastic net was used to identify the immune-related genes that significantly affected the DFS of patients. A prognostic risk model (IRGPM) for rectal cancer was constructed with the random forest method. The prognostic risk score was calculated by the model, and the patients were divided into high- and low-risk groups according to the median risk score. Immune characteristics were analyzed and compared between the high- and low-risk groups.

RESULTS

A total of 407 LARC samples were used in this study. A 20-gene signature was identified by elastic net and was found to be significantly correlated with DFS. The IRGPM was constructed on the basis of the 20 immune-related genes. Kaplan‒Meier survival analysis showed poorer 5-year DFS in the high-risk group than in the low-risk group, and the receiver operating characteristic (ROC) curve suggested good model prediction (areas under the curve (AUCs) of 0.87, 0.94, 0.95 at 1, 3, and 5 years, respectively). The model was validated in the GSE190826 cohort (AUCs of 0.79, 0.64, and 0.63 at 1, 3, and 5 years, respectively) and the cohort from our institution (AUCs of 0.64, 0.66, and 0. 64 at 1, 3, and 5 years, respectively). The differentially expressed genes between the high- and low-risk groups were enriched in cytokine‒cytokine receptor interactions. The patients in the low-risk group had higher immune scores than the patients in the high-risk group. Subsequently, we found that activated B cells, activated CD8 T cells, central memory CD8 T cells, macrophages, T follicular helper cells and type 2 helper cells were more abundant in the low-risk group. Moreover, we compared the expression of immune checkpoints and found that the low-risk group had a higher PDCD1 expression level.

CONCLUSION

The IRGPM, which was constructed based on the random forest and elastic net methods, is a promising method to distinguish DFS in LARC patients treated with a standard strategy. The low-risk group identified by IRGPM was characterized by the activation of adaptive immunity in tumor microenvironment.

First Demonstration of the Commissioning of a New Multi-Modality Radiotherapy Platform

PURPOSE/OBJECTIVE(S)

A new multi-modality radiotherapy platform was developed and introduced into clinical application, which has received US FDA 510k(K210921) and National Medical Products Administration (NMPA) clearance in China (20223050973). This study, for the first time, presents the technological characteristics and commissioning results of the new platform.

MATERIALS/METHODS

The platform consists of 3 modules: linear accelerator, rotating gamma system, and a kV imaging system within an O-ring gantry. The O-ring gantry can rotate continuously achieved by using a slip ring. The Linac delivers a 6 MV FFF photon beam with a variable dose rate of 50 to 1400 MU/min. The delivery techniques include 3D-CRT, IMRT, and VMAT. The rotating gamma system utilizes 18 Co-60 sources with a reference dose rate of 350 cGy/min. The image-guided techniques consist of kV-kV pairs and kV-CBCT. The X-ray intensity-modulated radiotherapy and γ-ray stereotactic radiotherapy can be delivered on the same platform. The acceptance test and commissioning were performed following the vendor's customer acceptance tests (CAT) and several AAPM Task Group reports/guidelines. Regarding the Linac, all applicable validation tests recommended by the MPPG 5.a (basic photon beam model validation, IMRT/VMAT validation, E2E tests, and patient-specific QA) were performed. For the rotating gamma system, the absorbed doses were measured using a PTW31014 and PTW60016. EBT3 films were employed to measure the relative output factors (ROFs). The E2E tests were performed using a PTW31014 and EBT3 films. The coincidence between the imaging isocenter and the Linac/gamma treatment isocenter was investigated using EBT3 films. The image quality was evaluated regarding the contrast-to-noise ratio (CNR), spatial resolution, and uniformity.

RESULTS

All tests included in the CAT met the vendor's specifications. All MPPG 5.a tests complied with the tolerances. The confidence limits for IMRT/VMAT validation were achieved according to TG-119. The point dose differences were below 1.68% and gamma pass rates (3%/2 mm) were above 95.9% for the Linac E2E tests. All plans of patient-specific QA had point dose differences below 1.79% and gamma pass rates (3%/2 mm) above 96.1% suggested by TG-218. For the rotating gamma system, the differences between the calculated and measured absorbed doses were below 1.86%. The ROFs calculated by the TPS were independently confirmed within 2% using EBT3 films. The point dose differences were below 2.57% and gamma pass rates (2%/1 mm) were above 95.3% for the E2E tests. The coincidence between the imaging isocenter and the Linac/gamma treatment isocenter was within 0.5 mm. The image quality fully complied with the vendor's specifications regarding the CNR, spatial resolution, and uniformity.

CONCLUSION

This is the first report about the commissioning of a new multi-modality radiotherapy platform. The platform has been successfully commissioned and exhibits good performance in mechanical and dosimetry accuracy.

Corrigendum to Autophagy and autophagy dysfunction contribute to apoptosis in HepG2 cells exposed to nanosilica. Toxicol Res (Camb),2016;5(3):871-882. doi:10.1039/c5tx00465a

[This corrects the article DOI: 10.1039/c5tx00465a.].

Erratum: Repeated Intravenous Administration of Silica Nanoparticles Induces Pulmonary Inflammation and Collagen Accumulation via JAK2/STAT3 and TGF-β/Smad3 Pathways in vivo [Corrigendum]

[This corrects the article DOI: 10.2147/IJN.S209458.].

Amorphous silica nanoparticles cause abnormal cytokinesis and multinucleation through dysfunction of the centralspindlin complex and microfilaments

BACKGROUND

With the large-scale production and application of amorphous silica nanoparticles (aSiNPs), its adverse health effects are more worthy of our attention. Our previous research has demonstrated for the first time that aSiNPs induced cytokinesis failure, which resulted in abnormally high incidences of multinucleation in vitro, but the underlying mechanisms remain unclear. Therefore, the purpose of this study was firstly to explore whether aSiNPs induced multinucleation in vivo, and secondly to investigate the underlying mechanism of how aSiNPs caused abnormal cytokinesis and multinucleation.

METHODS

Male ICR mice with intratracheal instillation of aSiNPs were used as an experimental model in vivo. Human hepatic cell line (L-02) was introduced for further mechanism study in vitro.

RESULTS

In vivo, histopathological results showed that the rate of multinucleation was significantly increased in the liver and lung tissue after aSiNPs treatment. In vitro, immunofluorescence results manifested that aSiNPs directly caused microfilaments aggregation. Following mechanism studies indicated that aSiNPs increased ROS levels. The accumulation of ROS further inhibited the PI3k 110β/Aurora B pathway, leading to a decrease in the expression of centralspindlin subunits MKLP1 and CYK4 as well as downstream cytokines regulation related proteins Ect2, Cep55, CHMP2A and RhoA. Meanwhile, the particles caused abnormal co-localization of the key mitotic regulatory kinase Aurora B and the centralspindlin complex by inhibiting the PI3k 110β/Aurora B pathway. PI3K activator IGF increased the phosphorylation level of Aurora B and improved the relative ratio of the centralspindlin cluster. And ROS inhibitors NAC reduced the ratio of multinucleation, alleviated the PI3k 110β/Aurora B pathway inhibition, and then increased the expression of MKLP1, CYK4 and cytokinesis-related proteins, whilst NAC restored the clustering of the centralspindlin.

CONCLUSION

This study demonstrated that aSiNPs led to multinucleation formation both in vivo and in vitro. ASiNPs exposure caused microfilaments aggregation and inhibited the PI3k 110β/Aurora B pathway through excessive ROS, which then hindered the centralspindlin cluster as well as restrained the expression of centralspindlin subunits and cytokinesis-related proteins, which ultimately resulted in cytokinesis failure and the formation of multinucleation.

Multiple and spectrally robust photonic magic angles in reconfigurable α-MoO3 trilayers

The emergence of a topological transition of the polaritonic dispersion in twisted bilayers of anisotropic van der Waals materials at a given twist angle-the photonic magic angle-results in the diffractionless propagation of polaritons with deep-subwavelength resolution. This type of propagation, generally referred to as canalization, holds promise for the control of light at the nanoscale. However, the existence of a single photonic magic angle hinders such control since the canalization direction in twisted bilayers is unique and fixed for each incident frequency. Here we overcome this limitation by demonstrating multiple spectrally robust photonic magic angles in reconfigurable twisted α-phase molybdenum trioxide (α-MoO₃) trilayers. We show that canalization of polaritons can be programmed at will along any desired in-plane direction in a single device with broad spectral ranges. These findings open the door for nanophotonics applications where on-demand control is crucial, such as thermal management, nanoimaging or entanglement of quantum emitters.

The detrimental effects of micro-and nano-plastics on digestive system: An overview of oxidative stress-related adverse outcome pathway

With the massive manufacture and use of plastics, plastic pollution-related environmental impacts have raised great concern in recent years. As byproducts of plastic fragmentation and degradation, microplastics (MPs) and nanoplastics (NPs) have been identified as novel pollutants that posed a threat to the ecosystem and humans. Since MPs/NPs could be transported via the food chain and retained in the water, the digestive system should be one of the major targets of MPs/NPs-related toxicity. Although considerable evidence has supported the digestive toxicity of MPs/NPs, the proposed mechanisms remained ambiguous due to the variety of study types, models, and endpoints. This review provided a mechanism-based perspective on MPs/NPs-induced digestive effects by adopting the adverse outcome pathway framework as a promising tool. The overproduction of reactive oxygen species was identified as the molecular initiating event in MPs/NPs-mediated injury to the digestive system. A series of detrimental effects including oxidative stress, apoptosis, inflammation, dysbiosis, and metabolic disorders were summarized as key events. Finally, the occurrence of these effects eventually led to an adverse outcome, suggesting a possible increase in the incidence of digestive morbidity and mortality.

Study on the value of the prenatal-postnatal integrated management model in the screening, diagnosis, and treatment of fetal heart malformations

OBJECTIVE

With the development and widespread use of fetal ultrasound and magnetic resonance technology in recent years, approximately 75% of fetuses are diagnosed prenatally with congenital structural malformations, a serious birth defect that endangers the life and health of the newborn. In this study, we aimed to study and analyze the value of the prenatal-postnatal integrated management model in the screening, diagnosis and treatment of fetal heart malformations.

PATIENTS AND METHODS

All pregnant women who were to undergo delivery in our hospital between January 2018 and December 2021 were recruited as the first subjects in this study, and after excluding those who refused to participate in the study, a total of 3,238 cases were finally included as subjects of this study. All pregnant women were screened for fetal heart malformations using the prenatal-postnatal integrated management model. Maternal files were established for all cases of heart malformations, grading the fetuses according to their heart disease grade, observing and recording their deliveries, treatment results and follow-ups.

RESULTS

After screening for heart malformations using the prenatal-postnatal integrated management model, 33 cases of heart malformations were identified, including 5 cases of Grade I (all delivered), 6 cases of Grade II (all delivered), 10 cases of Grade III (1 induced), and 12 cases of Grade IV (1 induced); 2 cases of ventricular septal defect healed spontaneously after delivery, and 18 infants were treated accordingly. The results of the later follow-up showed that 10 children had normalized their heart structure, 7 cases had slight alterations in the heart valves, and 1 case died.

CONCLUSIONS

The prenatal-postnatal integrated management model is a multidisciplinary cooperation model with certain clinical value in the screening, diagnosis and treatment of fetal heart malformations, which is beneficial to comprehensively improve the ability of hospital physicians in the grading management of heart malformations, detecting fetal heart malformations early and predicting fetal changes after birth. It further reduces the incidence of serious birth defects, conforms to the development trend of the diagnosis and treatment of congenital heart diseases, enables to reduce child mortality with timely treatment, effectively improves the surgical prognosis of critical and complex congenital heart diseases, with a promising application prospect.

[Expert consensus on late stage of critical care management]

We wished to establish an expert consensus on late stage of critical care (CC) management. The panel comprised 13 experts in CC medicine. Each statement was assessed based on the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) principle. Then, the Delphi method was adopted by 17 experts to reassess the following 28 statements. (1) ESCAPE has evolved from a strategy of delirium management to a strategy of late stage of CC management. (2) The new version of ESCAPE is a strategy for optimizing treatment and comprehensive care of critically ill patients (CIPs) after the rescue period, including early mobilization, early rehabilitation, nutritional support, sleep management, mental assessment, cognitive-function training, emotional support, and optimizing sedation and analgesia. (3) Disease assessment to determine the starting point of early mobilization, early rehabilitation, and early enteral nutrition. (4) Early mobilization has synergistic effects upon the recovery of organ function. (5) Early functional exercise and rehabilitation are important means to promote CIP recovery, and gives them a sense of future prospects. (6) Timely start of enteral nutrition is conducive to early mobilization and early rehabilitation. (7) The spontaneous breathing test should be started as soon as possible, and a weaning plan should be selected step-by-step. (8) The waking process of CIPs should be realized in a planned and purposeful way. (9) Establishment of a sleep-wake rhythm is the key to sleep management in post-CC management. (10) The spontaneous awakening trial, spontaneous breathing trial, and sleep management should be carried out together. (11) The depth of sedation should be adjusted dynamically in the late stage of CC period. (12) Standardized sedation assessment is the premise of rational sedation. (13) Appropriate sedative drugs should be selected according to the objectives of sedation and drug characteristics. (14) A goal-directed minimization strategy for sedation should be implemented. (15) The principle of analgesia must be mastered first. (16) Subjective assessment is preferred for analgesia assessment. (17) Opioid-based analgesic strategies should be selected step-by-step according to the characteristics of different drugs. (18) There must be rational use of non-opioid analgesics and non-drug-based analgesic measures. (19) Pay attention to evaluation of the psychological status of CIPs. (20) Cognitive function in CIPs cannot be ignored. (21) Delirium management should be based on non-drug-based measures and rational use of drugs. (22) Reset treatment can be considered for severe delirium. (23) Psychological assessment should be conducted as early as possible to screen-out high-risk groups with post-traumatic stress disorder. (24) Emotional support, flexible visiting, and environment management are important components of humanistic management in the intensive care unit (ICU). (25) Emotional support from medical teams and families should be promoted through"ICU diaries"and other forms. (26) Environmental management should be carried out by enriching environmental content, limiting environmental interference, and optimizing the environmental atmosphere. (27) Reasonable promotion of flexible visitation should be done on the basis of prevention of nosocomial infection. (28) ESCAPE is an excellent project for late stage of CC management.

MitoQ ameliorates PM2.5-induced pulmonary fibrosis through regulating the mitochondria DNA homeostasis

Pulmonary fibrosis is a severe pulmonary disease, and may related to PM_2.5 exposure. Our study aims to explore the pathogenesis of PM_2.5-induced pulmonary fibrosis, and MitoQ protective effect in this process. Our results find that inflammatory cells aggregation and pulmonary fibrosis in mice lung after PM_2.5 exposure. Moreover, Collagen I/III overproduction, EMT and TGF-β1/Smad2 pathway activation in mice lung and BEAS-2B after PM_2.5 exposure. Fortunately, these changes were partially ameliorated after MitoQ treatment. Meanwhile, severe oxidative stress, mitochondrial homeostasis imbalance, overproduction of 8-oxoG (7,8-dihydro-8-oxoguanine), as well as the inhibition of SIRT3/OGG1 pathway have founded in mice lung or BEAS-2B after PM_2.5 exposure, which were alleviated by MitoQ treatment. Collectively, our study found that oxidative stress, especially mitochondrial oxidative stress participates in the PM_2.5-induced pulmonary fibrosis, and MitoQ intervention had a protective effect on this progress. Moreover, mitochondrial DNA homeostasis might participate in the pulmonary fibrosis caused by PM_2.5 exposure. Our study provides a novel pathogenesis of PM_2.5-caused pulmonary fibrosis and a possible targeted therapy for the pulmonary diseases triggered by PM_2.5.

Twist-tunable polaritonic nanoresonators in a van der Waals crystal

Optical nanoresonators are key building blocks in various nanotechnological applications (e.g., spectroscopy) due to their ability to effectively confine light at the nanoscale. Recently, nanoresonators based on phonon polaritons (PhPs)-light coupled to lattice vibrations-in polar crystals (e.g., SiC, or h-BN) have attracted much attention due to their strong field confinement, high quality factors, and their potential to enhance the photonic density of states at mid-infrared (mid-IR) frequencies, where numerous molecular vibrations reside. Here, we introduce a new class of mid-IR nanoresonators that not only exhibit the extraordinary properties previously reported, but also incorporate a new degree of freedom: twist tuning, i.e., the possibility of controlling their spectral response by simply rotating the constituent material. To achieve this result, we place a pristine slab of the van der Waals (vdW) α-MoO3 crystal, which supports in-plane hyperbolic PhPs, on an array of metallic ribbons. This sample design based on electromagnetic engineering, not only allows the definition of α-MoO3 nanoresonators with low losses (quality factors, Q, up to 200), but also enables a broad spectral tuning of the polaritonic resonances (up to 32 cm-1, i.e., up to ~6 times their full width at half maximum, FWHM ~5 cm-1) by a simple in-plane rotation of the same slab (from 0 to 45°). These results open the door to the development of tunable and low-loss IR nanotechnologies, fundamental requirements for their implementation in molecular sensing, emission or photodetection applications.

Ferritinophagy was involved in long-term SiNPs exposure induced ferroptosis and liver fibrosis

SiNPs could induce liver fibrosisinvivo, but the mechanism was not completely clear. This study focused on exploring whether long-term SiNPs exposure at human-related exposure dosage could lead to ferritinophagy-mediated ferroptosis and liver fibrosis. In vivo, long-term SiNPs exposure induced liver fibrosis inrats accompanied by ferritinophagy and ferroptosis in hepatocytes. Interestingly, the progression of liver fibrosis was alleviated after exposure cessation and recovery, meanwhile ferritinophagy and ferroptosis were not further activated. In vitro, after long-term SiNPs exposure, the mitochondrial membrane ruptured, lipid peroxidation intensified, the level of redox active iron increased and the repair protein of lipid peroxidation were consumed in L-02 cells, demonstrating ferroptosis occurrence. Notably, NCOA4 knockdown inhibited ferritin degradation, alleviated the increase of intracellular ferrous iron level, reduced lipid peroxidation and the depletion of glutathione peroxidase 4 (GPX4). In conclusion, ferritinophagy mediated by NCOA4 was responsible for long-term SiNPs exposure induced hepatocytes ferroptosis and liver fibrosis, which provided a scientific basis for toxicological assessment of SiNPs and would be benefited for the safety design of SiNPs-based products.

Joint effect of multiple air pollutants on cardiometabolic health in normal-weight and obese adults: A novel insight into the role of circulating free fatty acids

The cardiometabolic effects of air pollution in the context of mixtures and the underlying mechanisms remain not fully understood. This study aims to investigate the joint effect of air pollutant mixtures on a broad range of cardiometabolic parameters, examine the susceptibility of obese individuals, and determine the role of circulating fatty acids. In this panel study, metabolically healthy normal-weight (MH-NW, n = 49) and obese (MHO, n = 39) adults completed three longitudinal visits (257 person-visits in total). Personal exposure levels of PM_2.5, PM₁₀, O₃, NO₂, SO₂, CO and BC were estimated based on fixed-site monitoring data, time-activity logs and infiltration factor method. Blood pressure, glycemic homeostasis, lipid profiles, systematic inflammation and coagulation biomarkers were measured. Targeted metabolomics was used to quantify twenty-eight plasma free fatty acids (FFAs). Bayesian kernel machine regression models were applied to establish the exposure-response relationships and identify key pollutants. Significant joint effects of measured air pollutants on systematic inflammation and coagulation biomarkers were observed in the MHO group, instead of the MH-NW group. Lipid profiles showed the most significant changes in both groups and O₃ contributed the most to the total effect. Specific FFA patterns were identified, and de novo lipogenesis (DNL)-related pattern was most closely related to blood lipid profiles. In particular, interaction analysis suggested that DNL-related FFA pattern augmented the effects of O₃ on triglyceride (TG, P_interaction = 0.040), high-density lipoprotein cholesterol (HDL-C, P_interaction = 0.106) and TG/HDL-C (P_interaction = 0.020) in the MHO group but not MH-NW group. This modification was further confirmed by interaction analysis with estimated activity of SCD1, a key enzyme in the DNL pathway. Therefore, despite being metabolically healthy, obese subjects have a higher cardiometabolic susceptibility to air pollution, especially O₃, and the DNL pathway may represent an intrinsic driver of lipid susceptibility. This study provides new insights into the cardiometabolic susceptibility of obese individuals to air pollution.

Adverse effects and underlying mechanism of amorphous silica nanoparticles in liver

Amorphous silica nanoparticles (SiNPs) have been widely used and mass-producted due to its unique properties. With the life cycle of SiNPs-based products, SiNPs are further released into the air, soil, surface water and sediment, resulting in an increasing risk to humans. SiNPs could enter into the human body through vein, respiratory tract, digestive tract or skin. Moreover, recent evidences have showed that, regardless of exposure pathways, SiNPs could even be traced in liver, which is gradually considered as one of the main organs that SiNPs accumulate. Increasing evidences supported the link between SiNPs exposure and adverse liver effects. However, the research models are diverse and the molecular mechanisms have not been well integrated. In this review, the liver-related studies of SiNPs in vivo and in vitro were screened from the PubMed database by systematic retrieval method. We explored the interaction between SiNPs and the liver, and especially proposed a framework of SiNPs-caused liver toxicity, considering AOP Wiki and existing studies. We identified increased reactive oxygen species (ROS) as a molecular initiating event (MIE), oxidative stress, endoplasmic reticulum stress, lysosome disruption and mitochondrial dysfunction as subsequent key events (KEs), which gradually led to adverse outcomes (AOs) containing liver dysfunction and liver fibrosis through a series of key events about cell inflammation and death such as hepatocyte apoptosis/pyroptosis, hepatocyte autophagy dysfuncton and hepatic macrophages pyroptosis. To our best knowledge, this is the first AOP proposed on SiNPs-related liver toxicity. In the future, more epidemiological studies need to be performed and more biomarkers need to be explored to improve the AOP framework for SiNPs-associated liver toxicity.

Association of long-term exposure to ambient air pollutants with cardiac structure and cardiovascular function in Chinese adults

Epidemiological evidence increasingly suggests that air pollutants are intimately associated with the incidence and mortality of cardiovascular diseases (CVDs). However, studies on the association between chronic exposure to air pollutants and changes in left cardiac function and structure are limited. In our cross-sectional study, 3145 participants were enrolled from 6 provinces to explore the relationship between long-term air pollutants, cardiac structure, and cardiovascular function (e.g., blood lipids, blood pressure and pulse) in Chinese adults. Our study showed that exposure to five pollutants (NO₂, O₃, PM₁, PM_2.5 and PM₁₀) was associated with reduced left ventricular systolic function based on EF and SV parameters. These pollutants were also associated with increased pulses, where smaller particle sizes correlated significantly with pulses. Second, except for O₃, four pollutants were associated with decreased left ventricular diastolic parameters LVIDd and EDV and increased cardiac structural parameter IVSd. In addition, exposures to NO₂, O₃ and PM₁₀ were positively correlated with triglycerides in blood lipids. Overall, this study showed that chronic pollutant exposure is strongly associated with impaired left ventricular function in Chinese adults.

Co-exposure of PM2.5 and high-fat diet induce lipid metabolism reprogramming and vascular remodeling

Fine particulate matter (PM_2.5) exposure has been proved to increase the cardiovascular disease risk. However, there is a lack of comprehensive knowledge on whether a high-fat diet (HFD) affects PM_2.5-induced cardiovascular disease. The purpose of this study was to investigate the impairment of lipid metabolism and vascular function by PM_2.5 and HFD exposure in ApoE^-/- mice. Oil red O staining indicated that co-treatment of PM_2.5 and HFD resulted in markedly lipid deposition in the mice aorta. Blood biochemical analysis demonstrated that co-exposure of PM_2.5 and HFD could cause dyslipidemia in vivo. Vascular Doppler ultrasound and histopathological analysis found that the functional and structural alterations with fibrosis and calcified remodeling of the vessels were detected after PM_2.5 and HFD exposure. For in-depth study, the genome-wide transcriptional analysis performed in macrophages was further revealed that the endoplasmic reticulum stress, immune system process, regulation of cell proliferation etc. were response to PM_2.5 exposure; while Lipid and atherosclerosis signaling pathways had a critical role in PM_2.5-induced vascular injury. Results from validation experiments manifested that the release of supernatant in PM_2.5- or ox-LDL-treated macrophages could decrease the cell viability and increase the lipid ROS in vascular smooth muscle cells (VSMCs). Moreover, the up-regulations of CCL2, IL-6 and IL-1β in aortic arch of mice were observed after co-exposure with PM_2.5 and HFD. Our data hinted that PM_2.5 could affect the lipid metabolism reprogramming and induce vascular remodeling, accompanied with synergistic effects of HFD.

A comprehensive understanding of ambient particulate matter and its components on the adverse health effects based from epidemiological and laboratory evidence

The impacts of air pollution on public health have become a great concern worldwide. Ambient particulate matter (PM) is a major air pollution that comprises a heterogeneous mixture of different particle sizes and chemical components. The chemical composition and physicochemical properties of PM change with space and time, which may cause different impairments. However, the mechanisms of the adverse effects of PM on various systems have not been fully elucidated and systematically integrated. The Adverse Outcome Pathway (AOP) framework was used to comprehensively illustrate the molecular mechanism of adverse effects of PM and its components, so as to clarify the causal mechanistic relationships of PM-triggered toxicity on various systems. The main conclusions and new insights of the correlation between public health and PM were discussed, especially at low concentrations, which points out the direction for further research in the future. With the deepening of the study on its toxicity mechanism, it was found that PM can still induce adverse health effects with low-dose exposure. And the recommended Air Quality Guideline level of PM_2.5 was adjusted to 5 μg/m³ by World Health Organization, which meant that deeper and more complex mechanisms needed to be explored. Traditionally, oxidative stress, inflammation, autophagy and apoptosis were considered the main mechanisms of harmful effects of PM. However, recent studies have identified several emerging mechanisms involved in the toxicity of PM, including pyroptosis, ferroptosis and epigenetic modifications. This review summarized the comprehensive evidence on the health effects of PM and the chemical components of it, as well as the combined toxicity of PM with other air pollutants. Based on the AOP Wiki and the mechanisms of PM-induced toxicity at different levels, we first constructed the PM-related AOP frameworks on various systems.

The critical role of epigenetic mechanisms involved in nanotoxicology

Over the past decades, nanomaterials (NMs) have been widely applied in the cosmetic, food, engineering, and medical fields. Along with the prevalence of NMs, the toxicological characteristics exhibited by these materials on health and the environment have gradually attracted attentions. A growing number of evidences have indicated that epigenetics holds an essential role in the onset and development of various diseases. NMs could cause epigenetic alterations such as DNA methylation, noncoding RNA (ncRNA) expression, and histone modifications. NMs might alternate either global DNA methylation or the methylation of specific genes to affect the biological function. Abnormal upregulation or downregulation of ncRNAs might also be a potential mechanism for the toxic effects caused by NMs. In parallel, the phosphorylation, acetylation, and methylation of histones also take an important part in the process of NMs-induced toxicity. As the adverse effects of NMs continue to be explored, mechanisms such as chromosomal remodeling, genomic imprinting, and m⁶ A modification are also gradually coming into the limelight. Since the epigenetic alterations often occur in the early development of diseases, thus the relevant studies not only provide insight into the pathogenesis of diseases, but also screen for the prospective biomarkers for early diagnosis and prevention. This review summarizes the epigenetic alterations elicited by NMs, hoping to provide a clue for nanotoxicity studies and security evaluation of NMs. This article is categorized under: Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials.

Melatonin alleviates PM2.5 -induced glucose metabolism disorder and lipidome alteration by regulating endoplasmic reticulum stress

Exposure to fine particulate matter (PM_2.5 ) was associated with an increased incidence of liver metabolic disease. Melatonin has been shown to prevent liver glucolipid metabolism disorders. However, whether melatonin could rescue PM_2.5 -induced liver metabolic abnormalities remains uncertain. This study was to evaluate the mitigating effect of melatonin on PM_2.5 -accelerated hepatic glucose metabolism imbalance in vivo and in vitro. Schiff periodic acid shiff staining and other results showed that PM_2.5 led to a decrease in hepatic glycogen reserve and an increase in glucose content, which was effectively alleviated by melatonin. Targeted lipidomics is used to identify lipid biomarkers associated with this process, including glycerolipids, glycerophospholipids, and sphingolipids. In addition, gene microarray and quantitative polymerase chain reaction analysis of ApoE^-/- mice liver suggested that PM_2.5 activated the miR-200a-3p and inhibited DNAJB9, and the targeting relationship was verified by luciferase reports for the first time. Further investigation demonstrated that DNAJB9 might motivate endoplasmic reticulum (ER) stress by regulating Ca²⁺ homeostasis, thus altering the protein expression of GSK3B, FOXO1, and PCK2. Meanwhile, melatonin effectively inhibited miR-200a-3p and glucose metabolism disorder. Knockout of miR-200a-3p in L02 cells revealed that miR-200a-3p is indispensable in the damage of PM_2.5 and the therapeutic effect of melatonin. In summary, melatonin alleviated PM_2.5 -induced liver metabolic dysregulation by regulating ER stress via miR-200a-3p/DNAJB9 signaling pathway. Our data provide a prospective targeted therapy for air pollution-related liver metabolism disorders.

Microarray analysis of mRNA expression profiles in liver of ob/ob mice with real-time atmospheric PM2.5 exposure

Epidemiological studies have demonstrated the association between exposure to fine particulate matter (PM_2.5) and the onset of non-alcoholic fatty liver disease (NAFLD). However, the potential biological mechanism is largely unknown. Our study was aimed to explore the impact of PM_2.5 on the transcriptome level in the liver of ob/ob mice by atmosphere PM_2.5 whole-body dynamic exposure system, and meanwhile preliminarily investigated the effects of metformin intervention in this process. More than three thousand differentially expressed genes (DEGs) was screened out by microarray analysis (p < 0.05, |FC|> 1.5). KEGG pathway enrichment analysis showed that these DEGs were mainly enriched in cancers, infectious diseases, and signal transduction, and the most significant pathways were thyroid hormone signaling pathway, chronic myeloid leukemia and metabolic pathways. Then, 12 hub genes were gained through weighted gene correlation network analysis (WGCNA) and verified by qRT-PCR. The expression of 5 genes in darkslateblue module (cd53, fcer1g, cd68, ctss, laptm5) increased after PM_2.5 exposure and decreased after metformin intervention. They were related to insulin resistance, glucose and lipid metabolism and other liver metabolism, and also neurodegenerative diseases. This study provided valuable clues and possible protective measures to the liver damage in ob/ob mice caused by PM_2.5 exposure, and further research is needed to explore the related mechanism in detail.

Metabolomics-based safety evaluation of acute exposure to electronic cigarettes in mice

INTRODUCTION

A growing number of epidemiological evidence reveals that electronic cigarettes (E-cigs) were associated with pneumonia, hypertension and atherosclerosis, but the toxicological evaluation and mechanism of E-cigs were largely unknown.

OBJECTIVE

Our study was aimed to explore the adverse effects on organs and metabolomics changes in C57BL/6J mice after acute exposure to E-cigs.

METHODS AND RESULTS

Hematoxylin and eosin (H&E) staining found pathological changes in tissues after acute exposure to E-cigs, such as inflammatory cell infiltration, nuclear pyknosis, and intercellular interstitial enlargement. E-cigs could increase apoptosis-positive cells in a time-dependent way using Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay. Oxidative damage indicators of reactive oxygen species (ROS), malondialdehyde (MDA) and 4-hydroxynonena (4-HNE) were also elevated after E-cigs exposure. There was an increasing trend of total glycerol and cholesterol in serum, while the glucose and liver enzymes including alanine aminotransferase (ALT), aspartate transaminase (AST), gamma-glutamyltranspeptidase (γ-GT) had no significant change compared to that of control. Further, Q Exactive high field (HF) mass spectrometer was used to conduct metabolomics, which revealed that differential metabolites including l-carnitine, Capryloyl glycine, etc. Trend analysis showed the type of compounds that change over time. Pathway enrichment analysis indicated that E-cigs affected 24 metabolic pathways, which were mainly regulated amino acid metabolism, further affected the tricarboxylic acid (TCA) cycle. Additionally, metabolites-diseases network analysis found that the type 2 diabetes mellitus, propionic acidemia, defect in long-chain fatty acids transport and lung cancer may be related to E-cigs exposure.

CONCLUSIONS

Our findings provided important clues for metabolites biomarkers of E-cigs acute exposure and are beneficial for disease prevention.

Combined exposure to PM2.5 and high-fat diet facilitates the hepatic lipid metabolism disorders via ROS/miR-155/PPARγ pathway

Environmental fine particulate matter (PM_2.5), which has attracted worldwide attention, is associated with the progression of metabolic-associated fatty liver disease (MAFLD). However, it is unclear whether dietary habit exacerbate liver damage caused by PM_2.5. The current study aimed to investigate the combined negative effects of PM_2.5 and high-fat diet (HFD) on liver lipid metabolism in C57BL/6J mice. Histopathological and Oil-Red O staining analysis illustrated that PM_2.5 exposure resulted in increased liver fat content in HFD-fed C57BL/6J mice, but not in standard chow diet (STD)-fed mice. And there was a synergistic effect between PM_2.5 and HFD on hepatic lipotoxicity. The increased ROS levels and augmented oxidative damage were evaluated in liver tissue of mice treated with PM_2.5 and HFD together. In addition, excessive ROS production could activate the miR-155/peroxisome proliferator-activated receptor gamma (PPARγ) pathway, including up-regulation of lipid accumulation-related protein expressions of recombinant liver X receptor alpha (LXRα), sterol regulatory element binding protein-1 (SREBP-1), stearoyl-CoA desaturase-1 (SCD1), fatty acid synthase (FAS) and acetyl-CoA carboxylase 1 (ACC1).The use of miR-155 inhibitors demonstrated the indispensable role of miR-155 in the activation of lipid-regulated proteins by PM_2.5 and palmitic acid (PA). Collectively, altering high-fat dietary habits could protect against MAFLD motivated by air pollution, and miR-155 might be an effective preventive and therapeutic target for this process.

Impact of PM2.5 exposure on plasma metabolome in healthy adults during air pollution waves: A randomized, crossover trial

Air pollution, especially PM_2.5 (particulate matter with an aerodynamic diameter ≤2.5 µm) in China, is severe and related to a variety of diseases while the potential mechanisms have not been clearly clarified yet. This study was conducted using a randomized crossover trial protocol among young and healthy college students. Plasma samples were collected before, during, and post two typical air pollution waves with a washout interval of at least 2 weeks under true and sham air purification treatments, respectively. A total of 144 blood samples from 24 participants were included in the final analysis. Metabolomics analysis for the plasma samples was completed by Ultrahigh Performance Liquid Chromatography-Mass Spectrometry (UPLC-MS). Orthogonal Partial Least Squares Discrimination Analysis (OPLS-DA) and linear mixed-effect models were used to identify the differentially expressed metabolites and their associations with PM_2.5 exposure. MetaboAnalyst 5.0 was further used to conduct pathway enrichment analysis and correlation analysis of differentially expressed metabolites. A total of 40 metabolites were identified to be differentially expressed between the true and sham air purification treatments, and eleven metabolites showed consistent significant changes upon outdoor, indoor, and time-weighted personal PM_2.5 exposures. Short-term exposure to PM_2.5 may cause disturbances in metabolic pathways such as linoleic acid metabolism, arachidonic acid metabolism, and tryptophan metabolism.

Effects of ambient air pollution on glycosylated hemoglobin: a systematic review and meta-analysis

Air pollution is one of the biggest environmental health problems in the world; accumulative studies have shown that air pollution was closely related to metabolism disorders. HbA1c is a stable indicator for blood glucose level monitoring. However, studies on the impact of ambient air pollution on HbA1c have inconsistent conclusions. The objective of the study is to explore the influence of ambient air pollution on HbA1c. By searching keywords, a systematic literature retrieval was carried out on PubMed, Cochrane Library, Web of Science, and Embase databases up to April 2022. Pooled percentage change (%-change) and 95% confidence intervals (95% CI) were estimated using random effect models for particulate matter (PM) and nitrogen dioxide (NO₂). A subgroup analysis of body mass index (BMI), study region, exposure period, sample size, sensitivity analysis, and publication bias detection was also performed. There were 8, 12, and 6 studies included in this meta-analysis to explore the association between PM₁₀, PM_2.5, NO₂, and HbA1c, respectively. The results showed that for every increase of 10 μg/m³ in PM₁₀, PM_2.5, and NO₂, the %-changes in HbA1c were 0.13%, 0.814%, and 0.02%, respectively. The subgroup analysis showed that exposure period, sample size, and BMI were associated with HbA1c in response to air pollution. PM₁₀, PM_2.5, and NO₂ exposure were significantly associated with increased HbA1c levels.

[Developmental and epileptic encephalopathy 85 caused by SMC1A gene truncating variation: 4 cases report and literature review]

Objective: To summarize the clinical phenotype of patients with developmental and epileptic encephalopathy 85 caused by SMC1A gene truncating variation. Methods: The clinical data of 4 patients with epileptic encephalopathy caused by SMC1A gene truncating variation from August 2016 to June 2020 were analyzed retrospectively. Related literatures up to October 2021 with the key words "SMC1A" "Developmental and epileptic encephalopathy 85" "SMC1A, epilepsy" and "SMC1A, truncating" in PubMed, CNKI, and Wanfang databases were searched. Relevant literature was summarized and reviewed. Results: These 4 patients were all female. The onset age of seizure were all in the infantile period. They were admitted to the hospital at 3, 2, 11 and 18 months respectively. Focal seizures occurred in all 4 patients, while 1 of them experienced infantile spasm. The characteristic of cluster was observed in all of them with an interval of 14 days to 5.0 months. The seizures were all refractory to different kinds of anti-seizure medications. All 4 patients had severe developmental retardation with microcephaly (head circumference<-2 s). The interictal electroencephalogram (EEG) was characterized by diffuse slow wave. The 4 SMC1A gene variants were p.Gly655fs, p.Glu811fs, p.Arg412fs and p.Ile143fs, all of which were de novo frameshift variation after parental validation. There were another 17 cases with SMC1A gene truncating variation reported in 6 English articles and 1 Chinese article. Among these 21 patients, who were all female, the onset of seizures occurred between 0.5 and 18.0 months of age. Seventeen cases (81%) had the characteristics of cluster attacks, and the intervals of attack cycles were different. Seizure types included generalized tonic-clonic seizure (12 cases (57%)), focal seizure (11 cases(52%)), myoclonic(4 cases(19%)), spasm (4 cases(19%)), atypical absence (3 cases(14%)), tonic seizure (2 cases (10%)), and atonia (1 case(5%)). In addition, 4 cases (19%) had status epilepsy. All patients had moderate to severe mental retardation. Microcephaly was found in all patients. Among 18 cases,EEG in 8 cases had diffuse slow wave background. Brain magnetic resonance imaging (MRI) was normal in 13 cases (62%). Other MRI changes included cerebellar atrophy (3 cases), thin corpus callosum (3 cases), and lateral ventricular enlargement (2 cases). Twenty patients did not respond well to antiepileptic drugs. Conclusions: The clinical phenotypes of patients with epilepsy encephalopathy 85 caused by SMC1A gene truncating variation are characterized by female, early-onset, clustering of seizures, development delay and microcephaly. Diffuse slow waves are shown in interictal EEG in partial. Response to treatment and prognosis are poor.

PM2.5 induce the defective efferocytosis and promote atherosclerosis via HIF-1α activation in macrophage

Epidemiological studies demonstrate that fine particulate matter (PM_2.5) promotes the development of atherosclerosis. However, the mechanism insight of PM_2.5-induced atherosclerosis is still lacking. The aim of this study was to explore the biological effects of hypoxia-inducible factor 1α (HIF-1α) on PM_2.5-triggered atherosclerosis. The vascular stiffness, carotid intima-media thickness (CIMT), lipid and atherosclerotic lesion were increased when von Hippel-Lindau (VHL)-null mice were exposed to PM_2.5. Yet, knockout of HIF-1α markedly decreased the PM_2.5-triggered atherosclerotic lesion. We firstly performed microarray analysis in PM_2.5-treated bone morrow-derived macrophages (BMDMs), which showed that PM_2.5 significantly changed the genes expression patterns and affected biological processes such as phagocytosis, apoptotic cell clearance, cellular response to hypoxia, apoptotic process and inflammatory response. Moreover, the data showed knockout of HIF-1α remarkably relieved PM_2.5-induced defective efferocytosis. Mechanistically, PM_2.5 inhibited the level of genes and proteins of efferocytosis receptor c-Mer tyrosine kinase (MerTK), especially in VHL-null BMDMs. In addition, PM_2.5 increased the genes and proteins of a disintegrin and metallopeptidase domain 17 (ADAM17), which caused the MerTK cleavage to form soluble MerTK (sMer) in plasma and cellular supernatant. The sMer was significantly up-regulated in plasma of VHL-null PM_2.5-exposed mice. Moreover, PM_2.5 could induce defective efferocytosis and activate inflammatory response through MerTK/IFNAR1/STAT1 signaling pathway in macrophages. Our results demonstrate that PM_2.5 could induce defective efferocytosis and inflammation by activating HIF-1α in macrophages, ultimately resulting in accelerating atherosclerotic lesion formation and development. Our data suggest HIF-1α in macrophages might be a potential target for PM_2.5-related atherosclerosis.

Global association between atmospheric particulate matter and obesity: A systematic review and meta-analysis

BACKGROUND

Among various air pollutants, particulate matter (PM) is the most harmful and representative pollutant. Although several studies have shown a link between particulate pollution and obesity, the conclusions are still inconsistent.

METHODS

We conducted a systematic review and meta-analysis to pool the effect of PM exposure on obesity. Five databases (including PubMed, Web of Science, Scopus, Embase, and Cochrane) were searched for relevant studies up to Jan 2022. Adjusted risk ratio (RR) with corresponding 95% confidence interval (CI) were retrieved from individual studies and pooled with random effect models by STATA software. Besides, we tested the stability of results by Egger's test, Begg's test, funnel plot, and using the trim-and-fill method to modify the possible asymmetric funnel graph. The NTP-OHAT guidelines were followed to assess the risk of bias. Then the GRADE was used to evaluate the certainty of evidence.

RESULTS

26 studies were included in this meta-analysis. 19 studies have shown that PM_2.5 can increase the risk of obesity per 10 μg/m³ increment (RR: 1.159, 95% CI: 1.111-1.209), while 15 studies have indicated that PM₁₀ increase the risk of obesity per 10 μg/m³ increment (RR: 1.092, 95% CI: 1.070-1.116). Besides, 5 other articles with maternal exposure showed that PM_2.5 increases the risk of obesity in children (RR: 1.06, 95% CI: 1.02-1.11). And we explored the source of heterogeneity by subgroup analysis, which suggested associations between PM and obesity tended to vary by region, age group, participants number, etc. The analysis results showed publication bias and other biases are well controlled, but most certainties of the evidence were low, and more research is required to reduce these uncertainties.

CONCLUSION

Exposure to PM_2.5 and PM₁₀ with per 10 μg/m³ increment could increase the risk of obesity in the global population.

Adverse outcome pathway of fine particulate matter leading to increased cardiovascular morbidity and mortality: An integrated perspective from toxicology and epidemiology

Fine particulate matter (PM_2.5) exposure is a major threat to public health, and is listed as one of the leading factors associated with global premature mortality. Among the adverse health effects on multiple organs or tissues, the influence of PM_2.5 exposure on cardiovascular system has drawn more and more attention. Although numerous studies have investigated the mechanisms responsible for the cardiovascular toxicity of PM_2.5, the various mechanisms have not been integrated due to the variety of the study models, different levels of toxicity assessment endpoints, etc. Adverse Outcome Pathway (AOP) framework is a useful tool to achieve this goal so as to facilitate comprehensive understanding of toxicity assessment of PM_2.5 on cardiovascular system. This review aims to illustrate the causal mechanistic relationships of PM_2.5-triggered cardiovascular toxicity from different levels (from molecular/cellular/organ to individual/population) by using AOP framework. Based on the AOP Wiki and published literature, we propose an AOP framework focusing on the cardiovascular toxicity induced by PM_2.5 exposure. The molecular initiating event (MIE) is identified as reactive oxygen species generation, followed by the key events (KEs) of oxidative damage and mitochondria dysfunction, which induces vascular endothelial dysfunction via vascular endothelial cell autophagy dysfunction, vascular fibrosis via vascular smooth muscle cell activation, cardiac dysregulation via myocardial apoptosis, and cardiac fibrosis via fibroblast proliferation and myofibroblast differentiation, respectively; all of the above cardiovascular injuries ultimately elevate cardiovascular morbidity and mortality in the general population. As far as we know, this is the first work on PM_2.5-related cardiovascular AOP construction. In the future, more work needs to be done to explore new markers in the safety assessment of cardiovascular toxicity induced by PM_2.5.

NcRNAs: Multi‑angle participation in the regulation of glioma chemotherapy resistance (Review)

As the most common primary tumour of the central nervous system, gliomas have a high recurrence rate after surgical resection and are resistant to chemotherapy, particularly high-grade gliomas dominated by glioblastoma multiforme (GBM). The prognosis of GBM remains poor despite improvements in treatment modalities, posing a serious threat to human health. At present, although drugs such as temozolomide, cisplatin and bevacizumab, are effective in improving the overall survival of patients with GBM, most patients eventually develop drug resistance, leading to poor clinical prognosis. The development of multidrug resistance has therefore become a major obstacle to improving the effectiveness of chemotherapy for GBM. The ability to fully understand the underlying mechanisms of chemotherapy resistance and to develop novel therapeutic targets to overcome resistance is critical to improving the prognosis of patients with GBM. Of note, growing evidence indicates that a large number of abnormally expressed noncoding RNAs (ncRNAs) have a central role in glioma chemoresistance and may target various mechanisms to modulate chemosensitivity. In the present review, the roles and molecular mechanisms of ncRNAs in glioma drug resistance were systematically summarized, the potential of ncRNAs as drug resistance markers and novel therapeutic targets of glioma were discussed and prospects for glioma treatment were outlined. ncRNAs are a research direction for tumor drug resistance mechanisms and targeted therapies, which not only provides novel perspectives for reversing glioma drug resistance but may also promote the development of precision medicine for clinical diagnosis and treatment.

[Rapid determination of 30 volatile organic compounds in workplace air by gas chromatography]

Objective: To establish a method for rapid detection of DB-WAX capillary column and determination of the workplace air in 30 kinds of volatile organic pollutants. Methods: In August 2020, N-pentane, n-hexane, methylcyclohexane, octane, Acetone, ethyl acetate, butanone, benzene, 3-pentanone, trichloroethylene, tetrachloroethylene, toluene, butyl acetate, 2-hexanone, Isoamyl acetate, ethylbenzene, p-xylene, m-xylene, amyl acetate, o-xylene, chlorobenzene, styrene, cyclohexanone, P-chlorotoluene, bromobenzene, M-dichlorobenzene, p-dichlorobenzene, O-dichlorobenzene, o-Chlorotoluene, 1, 2 , 4-trichlorobenzene of 30 kinds of substances in air were collected by activated carbon tube. After analysis by carbon disulfide, the analytical solution was analyzed by DB-WAX column and determined by FID detector. Results: The above 30 kinds of volatile organic pollutants had good separation effect, the correlation coefficient of the standard curve was above 0.999, the relative standard deviation was 0.1%-3.2%, the desorption efficiency was 77.0%-117.1% , the lower limit of quantitation was 0.33-5.33 μg/ml, and the lowest quantitation concentration was 0.22-3.55 mg/m(3), the recoveries ranged was 95.4%-104.9%. Conclusion: The method can effectively separate and accurately determine 30 volatile organic compounds in these workplaces, and the method is simple and quick.