Objective: To analyze the change trends in the body shape indicators and proportions of students in Harbin from 2010 to 2024, and to investigate ergonomic compatibility of functional dimensions of school desks and chairs with current student shape indicators, so as to provide a reference for revising furniture standards of desks and chairs. Methods: Between September and November of both 2010 and 2024, a combination of convenience sampling and stratified cluster random sampling was conducted across three districts in Harbin, yielding samples of 6 590 and 6 252 students, respectively. Anthropometric shape indicators cluding height, sitting height, crus length, and thigh length-and their proportional changes were compared over the 15-year period. The 2024 data were compared with current standard functional dimensions of school furniture. The statistical analysis incorporated t-test and Mann-Whitney U- test. Results: From 2010 to 2024, average height increased by 1.8 cm for boys and 1.5 cm for girls; sitting height increased by 1.5 cm for both genders; crus length increased by 0.3 cm for boys and 0.4 cm for girls; and thigh length increased by 0.5 cm for both genders. The ratios of sitting height to height, and sitting height to leg length increased by less than 0.1 . The difference between desk chair height and 1/3 sitting height ranged from 0.4-0.8 cm. Among students matched with size 0 desks and chairs, 22.0% had a desk to chair height difference less than 0, indicating that the desk to chair height difference might be insufficient for taller students. The differences between seat height and fibular height ranged from -1.4 to 1.1 cm; and the differences between seat depth and buttock popliteal length ranged from -9.8 to 3.4 cm. Among obese students, the differences between seat width and 1/2 hip circumference ranged from -20.5 to -8.7 cm, while it ranged from -12.2 to -3.8 cm among non obese students. Conclusion Current furniture standards basically satisfy hygienic requirements; however, in the case of exceptionally tall and obese students, ergonomic accommodations such as adaptive seating allocation or personalized adjustments are recommended to meet hygienic requirements.

To explore the absorption mechanism of APS-Ⅱ in vivo by establishing M cell model. First, Astragalus polysaccharides (APS) was divided into two different molecular weight polysaccharides APS-I ( > 2 000 kDa) and APS-II (10 kDa) by ultrafiltration, and APS-II (10 kDa) was prepared and fluorescently labeled. Meanwhile, M cell model was constructed by Caco-2 cells and Raji cells. The M cell model was treated with transport inhibitors to explore the transport of APS-Ⅱ on M cells. The results show that FITC has been successfully labeled to the end of APS-Ⅱ, and the M cell model was successfully constructed, which found that APS-Ⅱ could be transported by M cells, and four transport inhibitors of 5-(N-ethyl-N-isopropyl) amiloride (EIPA), genistein, dynasore and nocodazole indicated that APS-II may enter cells through clathrin and caveolin-mediated endocytosis.

Objective To design an experimental device for simulating the interface micro motion of bone trabecular prosthesis and carry out the finite element analysis.Methods The experimental device was composed of a screw-in cylinder with threads,a flexible hinge,a micro-motion rod,a trabecular prosthesis,a connecting rod and a fixation post.A model of the experimental device was constructed with SolidWorks software,and then imported into ABAQUS software to establish a finite element model.An axial displacement load was applied to the femur to analyze the effects of the position of the flexible hinge,the gap between the prosthesis and the femur and the length of the connecting rod on the micro motion.Results The interface micro motion produced by the experimental device increased with the distance of the flexible hinge from the lower end of the screwed-in cylinder;the gap between the prosthesis and the femur did not affect the interface micro motion when the gap was not lower than 20 μm;the interface micro motion rose with the length of the connecting rod.Conclusion The experimental device can accurately simulate the micro motion of different bone trabecular prosthesis interfaces,and can be used for studying the effect of the interface micro motion on osseointegration.[Chinese Medical Equipment Journal,2024,45(1):25-30]

Objective To investigate the effects of parecoxib sodium injection combined with dexmedetomidine hydrochloride injection on postoperative cognitive function and stress response in patients with osteoporotic compression fractures.Methods The patients with osteoporotic compression fractures were divided into treatment group and control group according to the treatment plan.The control group was given intravenous injection of dexmedetomidine hydrochloride injection 0.2 μg·kg-1load dose,then micro pump injection 0.2 μg·kg-1·min-1 maintenance dose,until 30 min before the end of the operation;patients in the treatment group were intravenously injected with parecoxib sodium injection 20 mg before local anesthesia and 30 min before the end of operation on the basis of the control group.The pain,sedation,hemodynamics[mean arterial pressure(MAP),heart rate(HR)],cognitive function and safety evaluation were compared between the two groups before operation(T0),2 h after operation(T1),6 h after operation(T2),12 h after operation(T3)and 24 h after operation(T4).Results There were 39 cases in the treatment group and 41 cases in the control group.Visual analogue scale(VAS)scores in treatment group and control group were(3.09±0.55)and(3.41±0.62)scores at T1;VAS scores were(3.02±0.57)and(3.35±0.48)scores at T2;VAS scores were(2.64±0.44)and(2.90±0.46)scores at T3;VAS scores were(2.02±0.41)and(2.35±0.47)scores at T4;MMSE scores were(25.28±1.57)and(24.33±1.42)scores at T2;MMSE scores were(28.16±1.01)and(27.25±0.89)scores at T4;MoCA scores were(24.63±1.60)and(23.59±1.25)scores at T2;MoCA scores were(27.20±0.97)and(26.48±0.83)scores at T4.There were statistically significant differences in the above indexes between the treatment group and the control group(all P＜0.05).Adverse drug reactions in the treatment group included bradycardia,hypotension,nausea vomiting and hypokalemia;adverse drug reactions in the control group included bradycardia,hypotension and nausea vomiting.The total incidence rates of adverse drug reactions were 12.82％and 9.76％,without statistically significant difference(P＞0.05).Conclusion Compared with using dexmedetomidine alone,parecoxib sodium combined with dexmedetomidine is beneficial for relieving postoperative pain in patients with osteoporotic compression fractures,improving postoperative cognitive function.

Antimony is a toxic metalloid and exhibits different geochemical properties in different valence states,leading to distinct migration,transformation,and behavioral patterns in the environment.To further study the transfer and source-sink relationship of antimony and its compounds in the earth's surface ecological environment,it is very important to accurately determine the isotopic composition of antimony with different speciations.In this study,a pretreatment method for chromatographic separation and determination of different speciation's antimony isotopes in water samples was established by using multi-collector inductively coupled plasma mass spectrometry(MC-ICP-MS)to measure the isotopic composition of different speciation's antimony.This method was successfully applied to detection of natural rainwater and groundwater samples from the Qilong mining area.During the pretreatment,5 mmol/L ethylenediaminetetraacetic acid dipotassium salt(EDTA)and 2 mmol/L potassium hydrogen phthalate(KHP)(pH 4.5)were used as mobile phase,successfully separating trivalent antimony(Sb(Ⅲ))and pentavalent antimony(Sb(Ⅴ))from water samples using a Hamilton PRP-X100 anion exchange chromatographic column.A series of single-factor experiments identified the optimal separation and determination conditions as a column temperature of 40 ℃ and a high-performance liquid pump flow rate of 1.5 mL/min.The recoveries of Sb(Ⅲ)and Sb(Ⅴ)from the standard solutions of Sb(Ⅲ)and Sb(Ⅴ),and the mixed oxidation states solutions were 99％±1％,103％±1％,106％±1％,and 101％±1％,respectively.Moreover,the isotopic compositions of different speciation's antimony remained consistent before and after the chromatographic column treatment,and the reliability of the method was verified by detecting different oxidation state antimony in the natural rainwater samples.This research might provide important technical support for further studies on the geochemical cycling of antimony and its compounds in the ecological environment of the Earth's surface.

Objective The leptin receptor,encoded by the LEPR gene,is involved in tumorigenesis.A potential functional variant of LEPR,rs1137101(Gln223Arg),has been extensively investigated for its contribution to the risk of digestive system(DS)cancers,but results remain conflicting rather than conclusive.Here,we performed a case-control study and subsequent meta-analysis to examine the association between rs1137101 and DS cancer risk. Methods A total of 1,727 patients with cancer(gastric/liver/colorectal:460/480/787)and 800 healthy controls were recruited.Genotyping of rs1137101 was conducted using a polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP)assay and confirmed using Sanger sequencing.Twenty-four eligible studies were included in the meta-analysis. Results After Bonferroni correction,the case-control study revealed that rs1137101 was significantly associated with the risk of liver cancer in the Hubei Chinese population.The meta-analysis suggested that rs1137101 is significantly associated with the risk of overall DS,gastric,and liver cancer in the Chinese population. Conclusion The LEPR rs1137101 variant may be a genetic biomarker for susceptibility to DS cancers(especially liver and gastric cancer)in the Chinese population.

Objective To investigate the protective effect of placental mesenchymal stem cells(P-MSCs)on pancreatic trauma(PT)in rats.Methods Sixty healthy adult male SD rats were randomly divided into control group,pancreatic trauma group(inject 1 ml of PBS solution locally in the pancreatic injury area and around the trauma area),and P-MSCs group[inject 1 ml of P-MSCs(1×106/ml)locally in the pancreatic injury area and around the trauma area],with 20 rats in each group.The pancreatic trauma rat model was established using a traumatic pressure of 400 kPa.Five rats were sacrificed at 1,3,5,and 7 d after modeling in each group,and serum and pancreatic tissue were collected.HE staining was used to observe the pathological changes of pancreatic tissue and pathological scores were performed.The ELISA method was used to measure the concentrations of serum amylase(AMS),lipase(LPS),tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),IL-10,and transforming growth factor-β1(TGF-β1),as well as the activities of myeloperoxidase(MPO)and superoxide dismutase(SOD)in pancreatic tissue.The TUNEL method was used to observe the level of apoptosis in pancreatic tissue was observed by the TUNEL method.Results Compared with control group,pancreatic trauma group and P-MSCs group showed significant differences after pancreatic trauma,including the generation of peritoneal fluid increased(P<0.05),the ratio of pancreas to body weight and the total score of pancreatic tissue pathological damage increased(P<0.05),and serum levels of AMS,LPS,TNF-α,IL-6,and MPO activity increased early and showed a decreasing trend over time(P<0.05),while anti-inflammatory factors IL-10 and SOD activity showed an increasing trend over time(P<0.01),level of TGF-β1 in the early decline showed an upward trend over time(P<0.01),and the apoptosis index(AI)significantly increased(P<0.001).Compared with pancreatic trauma group,P-MSCs group showed an improvement in the overall morphology of pancreatic tissue,the generation of peritoneal fluid decreased(P<0.001),the pancreas to body weight ratio and the total score of pancreatic tissue pathological damage decreased(P<0.05),and serum levels of AMS,LPS,IL-6,TNF-α and MPO activity returned to normal levels faster(P<0.05);and the rate of anti-inflammatory factors IL-10,TGF-β1 and SOD activity elevation increased(P<0.05),the AI increased(P<0.001).Conclusion P-MSCs can achieve therapeutic effects on pancreatic trauma in rats by promoting pancreatic tissue repair,reducing local and systemic inflammation,improving tissue oxidative stress,and enhancing pancreatic acinar cell apoptosis.

Objective To investigate the effect of hemoperfusion combined with sequential hemodiafiltration on pancreatic islet β cell function,nutritional status and inflammatory response in patients with diabetic nephropathy(DN).Methods One hundred patients with DN admitted to Nanyang Central Hospital from February 2022 to February 2023 were selected as the research subjects.They were divided into the control group and the observation group according to the random number table method,with 50 patients in each group.The patients in the control group were treated with sequential hemodiafil-tration,and the patients in the observation group were treated with sequential hemodiafiltration combined with hemoperfusion.The weight and height of patients in the two groups were measured before treatment and after 6-month treatment to calculate body mass index(BMI).The triceps skinfold(TSF)thickness was measured by using a skinfold caliper.The nutritional status of patients were evaluated by subjective global assessment(SCA)scores.Fasting venous blood was collected from patients in the two groups to measure the levels of fasting insulin(FINS)and fasting plasma glucose(FPG)by radioimmunoassay,and the homeostasis model assessment of insulin resistance(HOMA-IR)and homeostasis model assessment of beta-cell function(HOMA-β)were calculated;the levels of total cholesterol(TC),triglyceride(TG),high-density lipoprotein cholesterol(HDL-C)and low-density lipoprotein cholesterol(LDL-C)were measured by using the fully automatic biochemical analyzer,and the levels of serum C-reactive protein(CRP),tumor necrosis factor-α(TNF-α)and interleukin-6(IL-6)were measured by using the enzyme-linked immunosorbent assay.Results There was no significant difference in HOMA-β,FINS and HOMA-IR of patients between the control group and the observation group before treatment(P＞0.05).FINS and HOMA-IR of patients after treatment were significantly lower than those before treatment,while HOMA-β was significantly higher than that before treatment in the two groups(P＜0.05).After treatment,FINS and HOMA-IR of patients in the observation group were significantly lower than those in the control group,while HOMA-β was significantly higher than that in the control group(P＜0.05).There was no significant difference in BMI,TSF and SGA of patients between the control group and the observation group before treatment(P＞0.05).After treatment,BMI,TSF and SGA of patients in both groups were significantly higher than those before treatment;and BMI,TSF and SGA of patients in the observation group were significantly higher than those in the control group(P＜0.05).There was no significant difference in the levels of TC,TG,LDL-C and HDL-C of patients between the control group and the observation group before treatment(P＞0.05).After treatment,the levels of TC,TG and LDL-C of patients in both groups were significantly lower than those before treatment,while the HDL-C level of patients was significantly higher than that before treatment(P＜0.05).After treatment,the levels of TC,TG and LDL-C of patients in the observation group were significantly lower than those in the control group,while the HDL-C level of patients was significantly higher than that in the control group(P＜0.05).There was no significant difference in the levels of serum CRP,TNF-α and IL-6 of patients between the control group and the observation group before treatment(P＞0.05).After treatment,the levels of serum CRP,TNF-α and IL-6 of patients in both groups were significantly lower than those before treatment;and the levels of serum CRP,TNF-α and IL-6 of patients in the observation group were significantly lower than those in the control group(P＜0.05).Conclusion Sequential hemodiafiltration combined with hemoperfusion can significantly improve pancreatic islet βcell function,nutritional status and lipid metabolism in patients with DN and inhibit inflammatory response.

Objective To explore the diagnostic efficacy of serum 14-3-3β protein combined with fractional exhaled nitric oxide(FeNO)and conventional ventilatory lung function parameters in diagnosing bronchial asthma(referred to as"asthma")in children.Methods A prospective study included 136 children initially diagnosed with asthma during an acute episode as the asthma group,and 85 healthy children undergoing routine health checks as the control group.The study compared the differences in serum 14-3-3β protein concentrations between the two groups,analyzed the correlation of serum 14-3-3β protein with clinical indices,and evaluated the diagnostic efficacy of combining 14-3-3β protein,FeNO,and conventional ventilatory lung function parameters for asthma in children.Results The concentration of serum 14-3-3β protein was higher in the asthma group than in the control group(P<0.001).Serum 14-3-3β protein showed a positive correlation with the percentage of neutrophils and total serum immunoglobulin E,and a negative correlation with conventional ventilatory lung function parameters(P<0.05).Cross-validation of combined indices showed that the combination of 14-3-3β protein,FeNO,and the percentage of predicted value of forced expiratory flow at 75%of lung volume had an area under the curve of 0.948 for predicting asthma,with a sensitivity and specificity of 88.9%and 93.7%,respectively,demonstrating good diagnostic efficacy(P<0.001).The model had the best extrapolation.Conclusions The combination of serum 14-3-3β protein,FeNO,and the percentage of predicted value of forced expiratory flow at 75%of lung volume can significantly improve the diagnostic efficacy for asthma in children.

Objective To investigate the prevalence of tension-type headache(TTH)in children and adolescents aged 0-19 years globally in 1990-2021,and to provide a basis for the prevention and treatment of TTH.Methods Based on the Global Burden of Disease Study data,the age-standardized prevalence distribution of TTH and its changing trend were analyzed among the children and adolescents aged 0-19 years,with different sexes,age groups,sociodemographic index(SDI)regions and countries/territories.Results The age-standardized prevalence rate(ASPR)of TTH in children and adolescents aged 0-19 globally in 2021 was 17 339.89/100 000,which was increased by 1.73%since 1990.The ASPR in females was slightly higher than that in males(1990:17 707.65/100 000 vs 16 403.78/100 000;2021:17 946.29/100 000 vs 16 763.09/100 000).The ASPR in adolescence was significantly higher than that in school-aged and preschool periods(1990:27 672.04/100 000 vs 10 134.16/100 000;2021:28 239.04/100 000 vs 10 059.39/100 000).Regions with high SDI exhibited a higher ASPR than the other regions,with significant differences in prevalence rates across different countries.From 1990 to 2021,there was a slight increase in global ASPR,with an average annual percentage change(AAPC)of 0.06%.Females experienced a smaller increase than males based on AAPC(0.04%vs 0.07%).There was reduction in ASPR in preschool and school-aged groups,with an AAPC of-0.02%,while there was a significant increase in ASPR in adolescence,with an AAPC of 0.07%.ASPR decreased in regions with low-middle and low levels of SDI,with an AAPC of-0.02%and-0.04%,respectively,while it increased in regions with middle SDI,with an AAPC of 0.24%.Conclusions There is a consistent increase in the ASPR of TTH in children and adolescents aged 0-19 years globally,with significant differences across sexes,age groups,SDI regions and countries/territories.