Circadian rhythm is one of the biorhythms formed by organisms in the process of evolution to adapt to the rotation of the earth,which is manifested as a cyclical biorhythm of about 24 hours produced by the body under the control of the internal biological clock,coordinating sleep/wakefulness,body temperature regulation,endocrine time and other activities.Long-term circadian rhythm disorders can cause increased risk of metabolic disorders,gastrointestinal diseases,neurodegenerative diseasesand other illnesses.As a typical model animal,the aquatic organism zebrafish(Danio rerio)has been widely used in experimental studies of circadian rhythm.This paper introduces in detailthe operating mechanism of zebrafish circadian clock,the influencing factors of the input system,the genes and pathways of the circadian clock,and the physiological output,summarizes the application and advantages in circadian rhythm research,finally looks forward to future research and development,in order to provide theoretical support for circadian rhythm regulation mechanism research,related drug development and disease treatment strategies.

ObjectiveTo explore the effect of occupational stress on work-related musculoskeletal disorders (WMSDs) in electronics manufacturing workers. Methods A total of 392 front-line workers in two electronic manufacturing enterprises in Guangdong Province were selected as the research subjects using the judgment sampling method. The prevalence of WMSDs and the level of occupational stress of the research subjects were investigated using the Musculoskeletal Disorders Questionnaire and the Core Occupational Stress Scale. Results The total WMSDs detection rate was 39.5%, and the multi-site WMSDs detection rate was 30.6%. The detection rate of occupational stress was 14.8%. The total WMSDs detection rate and multi-site WMSDs detection rate in the occupational stress group were higher than those in the non-occupational stress group (65.5% vs 35.0%, 56.9% vs 26.0%, both P<0.01). Binary logistic regression analysis result showed that the risk of WMSDs in the occupational stress group was higher than that in the non-occupational stress group after adjusting the effect of confounding factors such as age, gender, job type and work days per week (P<0.01). Conclusion The occupational stress may increase the risk of WMSDs in electronics manufacturing workers. Reducing the level of occupational stress among workers in electronic manufacturing enterprises is beneficial for reducing the risk of WMSDs.

OBJECTIVE To investigate the effect and mechanism of acute exposure to sodium cyanide(NaCN)on brain nerve damage induced by closed hypoxia in mice.METHODS ① Mice were randomly divided into hypoxia+NaCN 0(hypoxia control group),2.56,3.8,and 5.1 mg·kg-1 groups.After ip adminis-tration of different concentrations of NaCN,the mice were immediately placed into a closed hypoxic tank and the hypoxia survival time was observed.②Mice were divided into normal control,NaCN 3.8 mg·kg-1,hypoxia(30 and 60 min)and NaCN 3.8 mg·kg-1+hypoxia(30 and 60 min)groups.After grouping,the pH,oxygen saturation(sO2),oxygen tension(pO2)and carbon dioxide partial pressure(pCO2)of arterial blood of mice were detected using an arterial blood gas analyzer.The cortical cerebral blood flow of mice was detected using a laser speckle imager.The dry and wet brain tissue were weighed separately,and the brain moisture content was calculated.The kit was used to detect the activity of total superoxide dismutase(T-SOD)and the content of malondialdehyde(MDA)in the hippocampus.TUNEL staining was used to detect the apoptosis rate of cells in the hippocampus.HE staining was used to detect path-ological changes in the hippocampus.RESULTS ①Compared with the hypoxic control group,the sur-vival time of mice in the hypoxic+NaCN groups was significantly prolonged(P<0.01).②Compared with the normal control group,the hypoxia 30 min group showed upregulation of arterial blood p CO2(P<0.05),downregulation of p O2(P<0.05).The hypoxia 60 min group showed upregulation of arterial blood p CO2(P<0.05)and downregulation of cortical cerebral blood flow(P<0.05).In the NaCN 3.8 mg·kg-1 group,arterial blood p O2 and s O2 were significantly downregulated(P<0.05),so was cortical cerebral blood flow(P<0.01),but MDA content and T-SOD activity were significantly upregulated(P<0.01),and the brain moisture content was increased(P<0.01).Compared with the hypoxia 30 min group,s O2 and p O2 of arterial blood in the NaCN+hypoxia 30 min group were significantly upregulated(P<0.05),while p CO2 was significantly downregulated(P<0.05).Compared with the hypoxia group at corresponding time points,the NaCN+hypoxia 30 or 60 min groups showed significant downregulation of cerebral blood flow(P<0.01),significant upregulation of MDA content and T-SOD activity(P<0.01),and signifi-cant upregulation of brain moisture content(P<0.01).HE staining results showed that the NaCN 3.8 mg·kg-1 group and the NaCN+hypoxia group(30 or 60 min)showed significant cell swelling and vacuolization in cells in the hippocampal tissue,a decrease in the number of neurons,nuclear pyknosis and deep staining.TUNEL fluorescence results showed that the NaCN 3.8 mg·kg-1 group significantly increased the apop-tosis rate of the mouse hippocampus compared with the normal control group(P<0.05).The NaCN+ hypoxia 30 and 60 min groups significantly increased the apoptosis rate of the mouse hippocampus compared with the hypoxia group at corresponding time points(P<0.05).CONCLUSION NaCN can exacerbate hypoxia induced decrease in cerebral blood flow,oxidative stress in brain tissue,and neuro-nal apoptosis in mice,thereby reducing oxygen consumption in closed hypoxic tanks and prolonging their survival time.The mechanism is related to reduced utility of cell oxygen,delaying CO2 accumulation and increasing free oxygen in vivo.

Background::The conversion of adenosine (A) to inosine (I) through deamination is the prevailing form of RNA editing, impacting numerous nuclear and cytoplasmic transcripts across various eukaryotic species. Millions of high-confidence RNA editing sites have been identified and integrated into various RNA databases, providing a convenient platform for the rapid identification of key drivers of cancer and potential therapeutic targets. However, the available database for integration of RNA editing in hematopoietic cells and hematopoietic malignancies is still lacking.Methods::We downloaded RNA sequencing (RNA-seq) data of 29 leukemia patients and 19 healthy donors from National Center for Biotechnology Information (NCBI) Gene Expression Omnibus (GEO) database, and RNA-seq data of 12 mouse hematopoietic cell populations obtained from our previous research were also used. We performed sequence alignment, identified RNA editing sites, and obtained characteristic editing sites related to normal hematopoietic development and abnormal editing sites associated with hematologic diseases.Results::We established a new database, "REDH", represents RNA editome in hematopoietic differentiation and malignancy. REDH is a curated database of associations between RNA editome and hematopoiesis. REDH integrates 30,796 editing sites from 12 murine adult hematopoietic cell populations and systematically characterizes more than 400,000 edited events in malignant hematopoietic samples from 48 cohorts (human). Through the Differentiation, Disease, Enrichment, and knowledge modules, each A-to-I editing site is systematically integrated, including its distribution throughout the genome, its clinical information (human sample), and functional editing sites under physiological and pathological conditions. Furthermore, REDH compares the similarities and differences of editing sites between different hematologic malignancies and healthy control.Conclusions::REDH is accessible at http://www.redhdatabase.com/. This user-friendly database would aid in understanding the mechanisms of RNA editing in hematopoietic differentiation and malignancies. It provides a set of data related to the maintenance of hematopoietic homeostasis and identifying potential therapeutic targets in malignancies.

Integrated Approaches to Testing and Assessment(IATA)is a toxicological assessment decision-making method that integrates existing information from various sources,including physical and chemical properties,animal testing,and non-animal testing.Through the evaluation and analysis of a series of iterative strategies,it ultimately obtains risk assessment conclusions,thereby providing a basis for risk management decisions regarding chemical substances.The use of IATA is becoming increasingly prevalent in such areas as ocular irritation and genotoxicity.This paper introduces the conceptual connotation of IATA,sorts out the framework elements and sequential processes,explains the commonly used framework construction methods,shares cases of application in various exposure scenarios,and finally envisions future research directions in order to provide better methodological support for the risk assessment of chemical substances.

Objective:To investigate COVID-19 vaccination status and relevant adverse reactions in patients with psoriasis treated with biological agents, and to explore the effect of COVID-19 vaccination on psoriatic lesions.Methods:Clinical data were collected from 572 psoriasis patients aged 18 - 60 years, who were registered in the management system of psoriasis patients treated with biological agents in the University of Hong Kong-Shenzhen Hospital from May 2019 to June 2021. The COVID-19 vaccination status was investigated by telephone interviews, and the vaccination-related information was obtained by fixed healthcare workers during a fixed time period according to a predesigned questionnaire. Measurement data were compared between two groups by using t test, and enumeration data were compared by using chi-square test or Fisher′s exact test. Results:The COVID-19 vaccination coverage rate was 43.13% (226 cases) among the 524 patients who completed the telephone interview, and was significantly lower in the biological agent treatment group (30.79%, 105/341) than in the traditional drug treatment group (66.12%, 121/183; χ2 = 60.60, P < 0.001) . The main reason for not being vaccinated was patients′ fear of vaccine safety (49.66%, 148/298) , followed by doctors′ not recommending (26.51%, 79/298) . In the biological agent treatment group after vaccination, the exacerbation of psoriatic lesions was more common in patients receiving prolonged-interval treatment (42.86%, 6/14) compared with those receiving regular treatment (4.40%, 4/91; Fisher′s exact test, P < 0.001) . Skin lesions were severely aggravated in two patients after COVID-19 vaccination, who ever experienced allergic reactions and whose skin lesions did not completely subside after the treatment with biological agents. Conclusions:The COVID-19 vaccination coverage rate was relatively low in the psoriasis patients treated with biological agents, and no serious adverse reaction was observed after vaccination. Prolonged-interval treatment due to COVID-19 vaccination ran the risk of exacerbation of skin lesions.

Objective: To investigate the oxidative stress injury of nano zinc oxide nanoparticles(ZnO NPs) on human myocardial cells (AC16) ，and to analyze the mechanism of ZnO NPs from the transcriptome level． Methods: Dynamic light scattering (DLS) was used to characterize and detect ZnO NPs．After AC16 cells were exposed to ZnO NPs at different doses and at different times，the cell survival rate was determined by CCK-8 method．AC16 cells were divided into control group，ZnO NPs (50，100，200 μmol /L) ，after 6 h treatment，the mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) were measured．AC16 cells were divided into control group，50 μmol /L ZnO NPs group and 200 μmol /L ZnO NPs group．After 6 h exposure，total RNA was extracted by TRIzol for transcriptome analysis ，and the differentially expressed genes were enriched by gene body ( GO) ，Kyoto Encyclopedia of Genes and Genomes (KEGG) . Results : The results of DLS showed that the hydrodynamic diameter was ( 192. 2 ± 1. 63 ) nm and the Zeta potential was ( －23. 26 ± 1. 05 ) mV． CCK-8 results showed that the survival rate of AC16 cells decreased with the increase of dose and time of exposure to ZnO NPs. Fluorescence quantification showed that with the increase of ZnO NPs exposure dose，MMP significantly decreased at 100 μmol /L ZnO NPs(P＜0. 05) ，and ROS significantly increased at 50 μmol /L ZnO NPs(P＜0. 05) ．Using the multifunctional microplate reader，it was observed that MMP and ROS were statistically significant at 100 and 50 μmol /L ZnO NPs，respectively，showing a decrease in MMP and an increase in ROS．Transcriptome analysis showed that 1 071 genes were enriched in the 50 μmol /L ZnO NPs group compared with the control group，including 561 up-regulated genes and 510 down-regulated genes．Compared with the control group，7 164 genes were enriched in 200 μmol /L ZnO NPs group，including 4 098 up-regulated genes and 3 066 down-regulated genes．GO and KEGG analysis showed that the differential genes were mainly concentrated in ROS，antioxidant activity，mitochondrial cytochrome C release，apoptosis and other signaling pathways． Conclusion ZnO NPs can decrease the survival rate of AC16 cells and induce mitochondrial damage and oxidative stress，among which ROS-mediated oxi- dative stress and mitochondrial function changes are important toxic mechanisms of ZnO NPs induced AC16 cytotoxicity.

AIM: To investigate the effect of flutamide on mitochondrial biogenesis and the regulating effect of anoxidative pathway Nrf2 on it. METHODS: Human hepatocyte HepG2 cells were treated with flutamide (0-50 μmol/L) for 24 h, then mtDNA copy number and protein expression of mitochondrial biogenesis were detected by RT-PCR and WB. The effects of ERK1/2 and the role of Nrf2 pathway in mitochondrial biogenesis were further observed by gene knockdown and protein activation/inhibition methods. RESULTS: Flutamide interfered mitochondrial biogenesis concentration-dependently, the mtDNA copy number, ERK1/2 and PGC-1α proteins increased with the dose. ERK1/2 inhibition and activation regulated flutamide-induced mtDNA copy number and PGC-1α expression, and inhibition of Nrf2 pathway also affected flutamide-induced mtDNA copy number and expression of PGC-1α, as well as ERK1/2 expression. CONCLUSION: Flutamide affects mitochondrial biogenesis, and the antioxidant pathway Nrf2 may be involved in the regulation of flutamine-induced mitochondrial biogenesis by regulating ERK1/2.

background The lead isotope ratios (LIR) differ among different sourced samples. Previous domestic and oversea studies on source tracing by LIR in human blood or urine mainly focused on the comparison of blood or urine samples from the same or different individuals, while few comparisons between biological and environmental samples, and the reported relative standard deviations (RSDs) of the main LIR (^207/206Pb and ^208/206Pb) fluctuate widely from 0.3% to 1%. Objective To optimize inductively coupled plasma mass spectrometry (ICP-MS), obtain a better RSD, and determine LIRs of human blood, urine, and related environmental samples. Methods The ICP-MS was optimized for operating conditions and parameters according to the sensitivity and RSD of LIR. The study subjects were 40 lead-exposed workers in a lead-acid battery factory and 2 lead poisoned children in a hospital. The samples included 40 blood and 40 urine samples from the workers before shift, 4 dust samples and 2 water samples in the workplace on the same day before shift, 2 blood and 3 urine samples from the children before hospital admission due to lead-poisoning, and 4 urine samples after medical treatment. After heating and acid digestion, the LIR (^207/206Pb and ^208/206Pb) of biological and environmental samples were determined by the optimized ICP-MS method. t-test and two-dimensional traceability graphics were adopted to analyze the detection results. Results The calibrated RSDs of the LIR (^207/206Pb and ^208/206Pb) of lead isotope standard solution were 0.11% and 0.08% respectively, and the NIST-SRM-981 actual values were 0.91531±0.00097 and 2.1670±0.0017, respectively. When the total concentration of lead was greater than 5 μg·L⁻¹, the RSD of each isotope ratio was stable gradually; when the total concentration of lead was between 10-80 μg·L⁻¹, the RSD was below 0.20%. There were statistically significant differences in the blood and urine LIR (^207/206Pb and ^208/206Pb) of the lead-exposed workers (t=5.831, P<0.001; t=21.021, P<0.001), the LIR (^207/206Pb and ^208/206Pb) between workplace dust samples and workers’ urine samples (t=−6.879, P=0.038; t=12.521, P<0.001), and the ^208/206Pb between workplace dust samples and workers’ blood samples (t=−10.46, P<0.001), except the ^207/206Pb between workplace dust samples and workers’ blood samples (t=−0.12, P=0.912). In the patients afflicted with lead poisoning, the projection points of LIR of blood and urine samples from the same individual were not at the same level in the two-dimensional model, nor was the LIR of urine samples before and after medical treatment of the same individual. Conclusion The optimized ICP-MS can control the RSD of main LIR (^207/206Pb and ^208/206Pb) below 0.20%. There are differences in the LIR distributions of different samples.

With the extensive use of plastic products and the sharp increase of plastic waste, microplastics produced by degradation in the natural environment and artificially added by industry have been detected in food, air, ocean, and even extreme geographical environment. The environmental pollution and the biological health hazards caused by this new type of pollutant has become a global scientific problem to be solved urgently. Zebrafish (Danio rerio), as a typical model organism, has been widely used to evaluate the environmental pollution and health hazards caused by microplastics. This review on the research progress of model animal zebrafish in toxicity evaluation of microplastics mainly emphasized the toxic effects of microplastics on selected organs of zebrafish, briefly introduced the influencing factors of toxicity induced by microplastics, discussed the standardization of experiments for the evaluation of microplastic toxicity using zebrafish, and finally explored the future research directions.