Background Metals and metalloids in fine particulate matter (PM_2.5) may cause damage to the respiratory and circulatory systems of the human body, and long-term exposure is prone to causing chronic poisoning, cancer, and other adverse effects. Objective To assess the distribution characteristics of metals and metalloids in outdoor PM_2.5 in a southern city of China, conduct source apportionment, and evaluate the associated health risks, thereby providing theoretical support for further pollution control measures. Methods PM_2.5 samples were collected in districts A, B, and C of a southern China city, and the concentrations of 17 metals and metalloids were detected by inductively coupled plasma-mass spectrometry (ICP-MS). Pollution sources were assessed through enrichment factor and principal components analysis, and the main pollution sources were quantified using absolute principal component scores-multivariate linear regression (APCS-MLR). Health risks were evaluated based on the Technical guide for environmental health risk assessment of chemical exposure (WS/T777—2021). Results The ambient air PM_2.5 concentrations in the city were higher in winter and spring, and lower in summer and autumn. The annual average concentrations of ambient PM_2.5 in districts A, B, and C were 36.7, 31.9, and 24.4 μg·m⁻³, respectively. The ambient PM_2.5 levels in districts B and C were below the second-grade limit set by the Ambient air quality standards (GB 3095—2012). The enrichment factors of cadmium (Cd), aluminum (Al), and antimony (Sb) were greater than 10, those of copper (Cu), lead (Pb), arsenic (As), nickel (Ni), mercury (Hg), and molybdenum (Mo) fell between 1 and 10, and those of manganese (Mn), vanadium (V), chromium (Cr), cobalt (Co), barium (Ba), beryllium (Be), and uranium (U) were below or equal to 1. The comprehensive evaluation of source analysis showed that the main pollution sources in districts A and C and the whole city were coal-burning. In district B, the main pollution source was also coal combustion, followed by industrial process sources and dust sources. The carcinogenic risks of As and Cr were between 1×10⁻⁶ and 1×10⁻⁴. However, the hazard quotients for 15 metals and metalloids in terms of non-carcinogenic risk were below 1. Conclusion Cr and As in the atmospheric PM_2.5 of the city present a certain risk of cancer and should be paid attention to. In addition, preventive control measures should be taken against relevant pollution sources such as industrial emission, dust, and coal burning.

Background Air pollution remains a critical public health issue, with persistent exposure to air pollutants continuing to pose significant health risks. Currently, research investigating the association between air pollution and myocardial infarction mortality in Shenzhen remains inadequate. Objective To quantitatively assess the association between air pollutants and myocardial infarction mortality in residents. Methods Based on the mortality surveillance system of Shenzhen Center for Disease Control and Prevention, we conducted a time-stratified case-crossover study of 10089 permanent residents who died from myocardial infarction in Shenzhen between 2013 and 2022. Using residential address information, we obtained individual-level exposure data for air pollutants from the China High Air Pollutants dataset and meteorological factors from the China Meteorological Administration Land Data Assimilation System. A time-stratified case-crossover study design was employed to construct a conditional logistic regression model to assess the association between short-term exposure to air pollutants and myocardial infarction mortality. The exposure-response relationship was visualized, and a comprehensive health risk assessment was performed. Results This study included a total of 10 089 cases of myocardial infarction deaths in Shenzhen. The median [interquartile range (IQR)] concentrations of fine particulate matter (PM_2.5), inhalable particulate matter (PM₁₀), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), carbon monoxide (CO), and ozone (O₃) in Shenzhen from 2013 to 2022 were 24.59 (20.19) μg·m⁻³, 42.85 (28.42) μg·m⁻³, 8.53 (3.39) μg·m⁻³, 29.47 (13.56) μg·m⁻³, 0.77 (0.27) mg·m⁻³, and 86.53 (51.39) μg·m⁻³, respectively. The moving average concentrations of PM_2.5 and PM₁₀ over the current day and the previous 2 days (lag02) showed the highest risk of myocardial infarction mortality, with an odds ratio (OR) and 95% confidence interval (95%CI) of 1.004 (1.001, 1.007) and 1.004 (1.002, 1.006), respectively. At lag05, SO₂ demonstrated the strongest association with the risk of myocardial infarction mortality, with an OR (95%CI) of 1.042 (1.019, 1.065). The exposure-response relationships of PM_2.5, PM₁₀, and SO₂ with myocardial infarction mortality were approximately linear, whereas NO₂ exhibited a nonlinear relationship. At lag05, the highest risk of myocardial infarction mortality associated with NO₂ exposure was observed when the NO₂ concentration was ≤21.92 μg·m⁻³, with an OR (95% CI) of 1.024 (1.003, 1.046). The health risk assessment indicated that, using the WHO Air Quality Guidelines as the reference, the local PM_2.5 and NO₂ exposure led to an excess mortality of 398 and 298 cases, respectively. The sensitivity analysis revealed that after adjusting for O₃ and restricting the study period to 2013—2019, the effect estimates for PM_2.5, PM₁₀, NO₂, and SO₂ on myocardial infarction mortality slightly increased. Conclusion Short-term exposure to air pollutants, including PM_2.5, PM₁₀, NO₂, and SO₂, could increase the risk of myocardial infarction mortality. This study provides important scientific evidence for environmental health risk assessment and environmental management in Shenzhen.

Objective To investigate the value of peripheral blood soluble interleukin-2 receptor(sIL-2R),CD4+lymphocyte percentage/CD8+lymphocyte percentage ratio(hereinafter referred to as CD4+/CD8+)and tumor necrosis factor-α(TNF-α)in evaluating the efficacy of chemotherapy in elderly patients with newly treated active pulmonary tuberculosis.Methods A total of 102 elderly patients with newly treated active tu-berculosis admitted to the hospital from December 2019 to December 2022 were enrolled in the study as the observation group,and 102 healthy people aged 60 and older who underwent physical examination in the hos-pital during the same period were enrolled as the control group.The levels of sIL-2R,TNF-α and CD4+/CD8+in peripheral blood were compared between the two groups,and the correlations between sIL-2R,TNF-α and CD4+/CD8+were analyzed.The observation group was treated with 2HRZE/4HR anti-tuberculosis treatment regimen.The levels of sIL-2R,TNF-α and CD4+/CD8+in peripheral blood of patients with different efficacy before treatment,1 month and 6 months after treatment in the observation group were compared.The correla-tion between sIL-2R,CD4+/CD8+,TNF-α levels and therapeutic effect was analyzed.The receiver operating characteristic(ROC)curve was used to analyze the efficacy of indicators in evaluating the efficacy of chemo-therapy in elderly patients.Results The levels of sIL-2R and TNF-α in the observation group were higher than those in the control group,while CD4+/CD8+was lower than that in the control group,and the differ-ences were statistically significant(P＜0.05).In the observation group,sIL-2R and TNF-α were negatively correlated with CD4+/CD8+(P＜0.05),sIL-2R was positively correlated with TNF-α(P＜0.05).After 1 month and 6 months of treatment,the levels of sIL-2R and TNF-α in patients with apparent efficacy were low-er than those in patients with efficacy,and the latter were lower than those in patients with no effect,while the CD4+/CD8+in patients with apparent efficacy was higher than that in patients with efficacy,and the latter was higher than that in patients with no efficacy,and the differences were statistically significant(P＜0.05).The levels of sIL-2R and TNF-α were negatively correlated with the efficacy(P＜0.05),and CD4+/CD8+was positively correlated with the efficacy(P＜0.05).ROC curve analysis showed that the area under the curve(AUC)of sIL-2R,CD4+/CD8+,and TNF-α used in combination to assess efficacy was significantly greater than the AUCs of the single indicators used in the assessment at each time point of treatment(P＜0.05),and the AUC of the combination of the indicators was greater after 6 months of treatment than after 1 month of treatment(P＜0.05).Conclusion The levels of sIL-2R,CD4+/CD8+and TNF-α are closely related to the ef-ficacy of chemotherapy in elderly patients with newly treated active pulmonary tuberculosis,and the combina-tion of the above indicators has certain reference value in evaluating the efficacy of chemotherapy in patients.

ObjectiveTo understand the characteristics of PM_2.5 pollution in the air of Pearl River Delta city in Guangdong Province under the COVID-19 epidemic and the health risks of inhaling elements in PM_2.5. MethodsIn 2022， 10 PM_2.5 monitoring points were set up in 10 districts in Guangzhou， Shenzhen， Foshan and Zhuhai， and air samples were collected for 7 consecutive days every month to analyze the concentration of PM_2.5 and the 12 elements in PM_2.5. The classic "four-step" method was used to evaluate the carcinogenic risk and chronic non-carcinogenic risk of the elements in air PM_2.5 on health. The age-sensitive characteristics of metal elements were combined in the carcinogenic risk assessment， and age-sensitive factors were introduced to analyze the impact of air pollution on population health. ResultsA total of818 samples were collected. and the average annual PM_2.5 concentration in the four cities of the Pearl River Delta was 30.17 （1.00-166.00， s=21.06） μg·m^-3， which was lower than the concentration limit of the secondary standard of the Ambient Air Quality Standard （GB 3095-2012）. The difference of PM_2.5 concentration in the four cities was statistically significant. The PM_2.5 concentrations in Zhuhai and Shenzhen， which were located near the sea， were lower than those in Guangzhou and Foshan. The monthly mean concentration of PM_2.5 in the four cities was the lowest at 13.70 （4.00-34.00， s=5.93） μg·m^-3 in July and the highest at 57.73 （14.00-146.00， s=27.96） μg·m^-3 in January， showing a low concentration from May to October and a high concentration from November to April of the following year. The average daily PM_2.5 concentration exceeded the secondary standard for 29 days， mainly distributed in January and November. The average annual mass concentration of elements in PM_2.5 in the four cities was Al>Mn>Pb>As>Ni>Cr>Se>Sb>Cd>Tl>Be>Hg. AS and Mn have chronic non-carcinogenic risk in population， while Cr， AS， Cd， Be and Ni have carcinogenic risk in population. ConclusionThe PM_2.5 pollution levels of the four cities in the Pearl River Delta are low and variable. Coastal cities are lower than non-coastal cities， which shows the characteristics of first decreasing and then increasing throughout the year. The order of mass concentration of metal elements of PM_2.5 in four cities is basically the same except Be and Ni. As and Mn in PM_2.5 show a certain degree of chronic non-carcinogenic risk， and As， Cr， Cd， Ni and Be have a certain degree of carcinogenic risk. The four cities need to take effective intervention measures to continue to strengthen the pollution control and health protection of Cr， As， Cd and Mn in the air， and control the health burden caused by air pollution.

Based on the original data of cervical spine,the models of cervical C6 and C7 segments were reconstructed through medical image processing and reverse modeling operations,then the models were assembled to obtain the basic data of interbody fusion cage.According to the basic data,the structures of rectangular porous,gradient porous and octahedral porous interbody fusion cages were established respectively.Maximum force on the adult male neck was applied to the fusion device,and the stress,strain and maximum deformation of the fusion device were solved by finite element analysis.The elastic modulus decrease of the design,and the rectangular porosity structures with different porosity were analyzed and optimized.The results showed that the elastic modulus of the fusion cage with three structures decreased in varying degrees,and the porosity of the interbody fusion cage with rectangular structure was about 60％,which was the most decreased elastic modulus.

Objective To investigate the correlation between abdominal obesity and autoimmune thyroid disease in the view point of helper T cells and cytokines.Methods Clinical and laboratory data were collected from 108 pa-tients with Hashimoto's thyroiditis(HT)plus abdominal obesity and 122 patients of Hashimoto's thyroiditis without abdominal obesity who visited the People's Hospital of Xinjiang Uygur Autonomous Region and also from the control population.Abdominal circumference was measured,and patients in the HT patients were grouped according to whether they were abdominally obese or not.The thyroglobulin antibody(TgAb)and thyroid peroxidase antibody(TPOAb)were detected,and the ratio of helper T cells and related cytokines were detected by flow cytometry and enzyme-linked immunosorbent assay.Results The abdominal circumference of the TgAb-positive group was higher than that of the TgAb-negative group(P＜0.05).Correlation analysis suggested that abdominal circumference was significantly and positively correlated with TgAb and IL-4 but negatively correlated with Th1.After correcting for gender and age,and abdominal obesity and IL-4 were risk factors for TgAb antibody positivity OR=3.080(95％CI:1.022-9.284)and OR=1.296(95％CI:1.022-9.284),both with P＜0.05.Conclusions Abdominal obesity may be an influential factor in TgAb antibody positivity,with larger abdominal circumference having higher TgAb antibody titers,lower Th1 levels,and higher IL-4 levels.Visceral adiposity may exacerbate autoimmune dam-age of thyroid tissue by disruption of helper T cell pathway.

Venous thromboembolism(VTE)is a prevalent complication in orthopedics.In recent years,machine learning has been widely applied in orthopedics.The essence of machine learning lies in utilizing algorithms to analyze vast amounts of data and construct risk prediction models that can accurately forecast unknown clinical outcomes.By integrating high-risk factors,machine learning aids medical professionals in precisely identifying and screening individuals with a high risk of VTE and offering them timely individualized interventions.This article reviews the concept and classification of machine learning,the advantages of machine learning in enhancing model prediction ability,and the current application status of machine learning in constructing risk prediction models for patients with VTE.

Objective:To analyze the clinical features and genetic characteristics of a patient with Shwachman-Diamond syndrome (SDS) due to compound heterozygous variants of SBDS gene.Methods:A female child with SDS who was admitted to the Children's Hospital Affiliated to Zhengzhou University in February 2022 was selected as the study subject. Clinical data of the child was collected. Peripheral blood samples of the child and her elder sister and parents were collected and subjected to whole exome sequencing (WES). Candidate variant was verified by Sanger sequencing.Results:The child, a 1-year-and-1-month-old girl, had mainly manifested with diarrhea, hematochezia, growth retardation and malnutrition, along with increased transaminases and decreased neutrophils and hemoglobin. The anteroposterior X-ray of her left wrist indicated significantly delayed bone age. Colonoscopy revealed that her colorectal mucosa was erosive with oily food residues attached to the intestinal lumen. Genetic testing revealed that she has harbored c. 258+ 2T>C and c. 100A>G compound heterozygous variants of the SBDS gene. The c. 258+ 2T>C variant has derived from her father and known to be pathogenic, whilst the other has derived from her mother. Based on the guidelines from the American College of Medical Genetics and Genomics, the c. 100A>G variant was classified as likely pathogenic (PM1+ PM2_Supporting+ PM3+ PM5+ PP3). Conclusion:The compound heterozygous variants of c. 258+ 2T>C and c. 100A>G probably underlay the SDS in this child. For children with refractory diarrhea, liver damage and growth retardation, SDS should be suspected, and genetic testing can facilitate the diagnosis and treatment.

Objective:To explore the average age at onset of endometrial cancer (EC) and the differences between domestic and international factors.Methods:Pubmed, Wanfang Database, VIP Information Resource System, and China National Knowledge Infrastructure (CNKI) were selected to extract clinical research data related to EC. Through data mining methods such as frequency analysis and cluster analysis, we compared the differences in the average age of onset of EC between domestic and foreign countries.Results:A total of 280 articles that met the inclusion criteria were selected, and frequency analysis found that the average age of onset of EC in the Chinese population was mostly concentrated under 57 years old, while in European and American countries, it was mainly concentrated above 57 years old. Through cluster analysis, it was found that the average age of onset in China was clustered in one category with most Asian countries, while European and American countries and Australian countries were clustered in another category. Through analysis of domestic and foreign articles, it was found that the average age of onset of EC did not show a significant upward or downward trend with years.Conclusions:There are differences in the average onset age of EC among different countries and regions. The onset age of EC in Asian populations is significantly earlier than that in European and American populations. The average onset age of EC in Chinese populations is 54 years old, and there is no trend towards a younger onset of EC.

Objective:To investigate the value of ultrasonography in diagnosis of transposition of great arteries of the fetus at 11-13 + 6 weeks gestation. Methods:A prospective study was conducted on fetuses screened by ultrasound in the first trimester in Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region between January 2015 and March 2022. Fetal heart structure was screened by three-section screening method. Fetuses with suspected transposition of the great arteries at 11-13 + 6 weeks gestation underwent followed-up ultrasound examination, chromosome and gene test results. The ultrasound characteristics and prognosis pregnancy outcomes were summarized. Results:Twenty-one cases of transposition of the great arteries were detected by ultrasonography, including complete transposition of great arteries (20 cases) and congenitaly corrected transposition of the great arteries (1 case). Two cases were miss diagnosed. Twenty-one cases showed parallel signs of two major arteries on grayscale outflow section at 11-13 + 6 weeks gestation. There were 6 cases with aneuploid ultrasonographic soft markers abnormality, 2 cases with extracardiac malformation. Chromosome and microarray analysis were performed in 13 cases. 4 cases with chromosomal abnormality. Four cases of chromosomal abnormalities were associated with ultrasonographic soft markers abnormality, and 1 case with extracardiac malformation.In the 23 cases, 20 cases were induced, 1 miscarried, and 2 delivered to term. Among the fetuses delivered at term, 1 case died before neonatal operation and 1 case survived. Conclusions:Standardized ultrasound scan at 11-13 + 6 weeks has high accuracy in diagnosis of transposition of the great arteries. And the incidence of chromosomal abnormality is high with ultrasonographic soft markers abnormality or extracardiac malformation.