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.

ObjectiveThis study leverages structural data from antigen-antibody complexes of the influenza A virus neuraminidase (NA) protein to investigate the spatial recognition relationship between the antigenic epitopes and antibody paratopes. MethodsStructural data on NA protein antigen-antibody complexes were comprehensively collected from the SAbDab database, and processed to obtain the amino acid sequences and spatial distribution information on antigenic epitopes and corresponding antibody paratopes. Statistical analysis was conducted on the antibody sequences, frequency of use of genes, amino acid preferences, and the lengths of complementarity determining regions (CDR). Epitope hotspots for antibody binding were analyzed, and the spatial structural similarity of antibody paratopes was calculated and subjected to clustering, which allowed for a comprehensively exploration of the spatial recognition relationship between antigenic epitopes and antibodies. The specificity of antibodies targeting different antigenic epitope clusters was further validated through bio-layer interferometry (BLI) experiments. ResultsThe collected data revealed that the antigen-antibody complex structure data of influenza A virus NA protein in SAbDab database were mainly from H3N2, H7N9 and H1N1 subtypes. The hotspot regions of antigen epitopes were primarily located around the catalytic active site. The antibodies used for structural analysis were primarily derived from human and murine sources. Among murine antibodies, the most frequently used V-J gene combination was IGHV1-12*01/IGHJ2*01, while for human antibodies, the most common combination was IGHV1-69*01/IGHJ6*01. There were significant differences in the lengths and usage preferences of heavy chain CDR amino acids between antibodies that bind within the catalytic active site and those that bind to regions outside the catalytic active site. The results revealed that structurally similar antibodies could recognize the same epitopes, indicating a specific spatial recognition between antibody and antigen epitopes. Structural overlap in the binding regions was observed for antibodies with similar paratope structures, and the competitive binding of these antibodies to the epitope was confirmed through BLI experiments. ConclusionThe antigen epitopes of NA protein mainly ditributed around the catalytic active site and its surrounding loops. Spatial complementarity and electrostatic interactions play crucial roles in the recognition and binding of antibodies to antigenic epitopes in the catalytic region. There existed a spatial recognition relationship between antigens and antibodies that was independent of the uniqueness of antibody sequences, which means that antibodies with different sequences could potentially form similar local spatial structures and recognize the same epitopes.

Aim To explore the impacts of high mobility group box 1 (HMGB1) on the phenotypes, endocy-tosis and extracellular signal-regulated kinase (ERK)/ Jun N-terminal protein kinase (JNK)/P38 mitogen-ac-tivated protein kinase (MAPK) signaling pathway in indoxyl sulfate (IS) -induced dendritic cells (DCs). Methods After treatment with 30, 300 and 600 (xmol · L

Methamphetamine(METH)is highly addictive and neurotoxic,which causes cognitive and memory dysfunction in abusers.The harm of METH lies not only in its own toxicity,but also in the high physical and mental dependence of drug addicts,often causing mental disorders and violent behavior,bringing great safety risks to society.Non-coding RNA(ncRNA)does not encode proteins and is an important factor in regulating gene expression at the post-transcriptional level.Studies have shown that ncRNA plays an important regulatory role in methamphetamine-induced addiction and neurotoxicity,but the specific mechanism is unclear.This article reviews the current research progress of ncRNA in regulating METH-induced addiction and neurotoxicity to provide a reference for ncRNA as a forensic identification index and potential therapeutic target for METH abusers.

Glycosylation is one of the most important reactions in living organisms as it results in the formation of glycoconjugates with diverse biological functions. Sugar nucleotides are structurally composed of sugar and nucleoside diphosphate or monophosphate, which are widespread within a variety of biological cells. As glycosyl donors for the transglycosyl reactions catalyzed by Leloir-type glycosyltransferases, sugar nucleotides are essential for the synthesis of glycans and glycoconjugates. However, high costs and limited availability of nucleotide sugars prevent applications of biocatalytic cascades on an industrial scale. Therefore, attentions on synthetic strategies of sugar nucleotides have been increasing to achieve their wide applications in various fields. The 9 common sugar nucleotides in mammals have been fully studied with large-scale synthesis through chemical, enzymatic (chemo-enzymatic) and cell factory strategies. In addition to common sugar nucleotides, many rare sugar nucleotides are present in plants and bacteria. Although unnatural sugar nucleotides cannot be synthesized in organisms, they have great potential in research as substrates for glycosyltransferases in carbohydrate synthesis, as enzyme inhibitors in biochemical studies, and as components of glycoconjugate biosynthesis. Therefore, increasing attention has been paid to explore the efficient synthesis of unnatural sugar nucleotides. Currently, strategies for chemical synthesis of sugar nucleotides have been greatly improved, such as the use of effective catalysts for forming pyrophosphate bonds and the development of entirely new synthesis protocols. Multiple sugar nucleotides, especially unnatural sugar nucleotides, are synthesized chemically. However, chemical synthesis requires tedious protection and deprotection steps, resulting in complex steps, high cost and low yield. In contrast, enzymatic (chemo-enzymatic) and cell factory methods have significant advantages such as high yield, easy operation and easy process scale-up in the preparation of sugar nucleotides. Hence, they are prominent strategies for sugar nucleotide preparation. Herein, the biosynthesis and application of sugar nucleotides are reviewed, mainly focusing on the 9 sugar nucleotides common in mammals. The early strategies for enzymatic synthesis of sugar nucleotides generally used de novo synthesis pathway. With the discoveries of enzymes involved in salvage pathway of sugar nucleotide synthesis and the development of one-pot multienzyme (OPME) method, the synthesis of sugar nucleotides was greatly simplified. Cell factory method employs the microbial living cells as a “processing plant” by engineering their metabolic pathways through genetic engineering technology. The cell factory method has high yield, and has been applied for efficient synthesis of several sugar nucleotides. Moreover, the strategy of gram-scale synthesis of multiple rare sugar nucleotides by cascade reactions from common sugar nucleotides using sugar nucleotides synthases cloned from different sources was illustrated. In recent years, the synthesis cost of sugar nucleotides has been further reduced through various ways, such as regeneration of nucleotides, regeneration of organic cofactors, and application of immobilized enzyme technology. Furthermore, through the continuous improvement of sugar nucleotide purification process, the use of high concentration of multi-enzyme cascade and rapid non-chromatographic purification process, the synthesis of multiple sugar nucleotides and their derivatives from monosaccharides was achieved, which gradually broke the limitations of the existing strategy. With the efficient synthesis of sugar nucleotides, their applications in various fields have been increasingly explored, including the synthesis of glycans and glycoconjugates, biochemical characterization of glycosyltransferases and bioorthogonal labeling strategies, which are of great significance to the research of biochemistry, glycobiology and the development of related pharmaceutical products.

Objective To analyze the risk factors for severe illness caused by coronavirus disease 2019 in Fuzhou city.Methods The data of 4081 confirmed cases with current address in Fuzhou was collected from China Information System for Disease Control and Prevention from January 1 to June 30,2023.The epidemiological data of those cases was investigated such as the demographic characteristics,clinical manifestations and past medical history,etc.The risk factors of severe cases were analyzed by using the logistic regression.Results 4081 confirmed cases had been reported including 671 severe cases and 3410 non-severe cases.The demographic characteristics of severe cases,such as the proportion of male,age and current address in community were higher than that of non-severe cases,vaccination rate was lower than non-severe cases(59.02%vs.80.12%),the differences are statistically significant(P＜0.001).The clinical manifestations such as interval time between onset and visit(P=0.001),fever(P=0.002),difficulty in breathing/shortness of breath(P=0.001)were the factors related to severe illness.The past medical histories such as history of chronic lung disease,history of heart cerebrovascular disease of severe cases,were higher than that of non-severe cases(P＜0.001).Multivariate logistic regression showed that the male,the higher age,current address in community,no vaccination,the longer interval time between onset and visit,fever,difficulty in breathing/shortness of breath,the history of chronic lung disease,the history of heart cerebrovascular disease raised the risk of becoming severe cases.The healing time for severe cases was longer than that for non-severe cases(P＜0.001).Conclusion Sex,age,current address,vaccination,interval time between onset and visit,fever,difficulty in breathing/shortness of breath,history of chronic lung disease,and history of heart cerebrovascular disease are the influencing factors for severe illness.

Objective:To investigate the reasonable airflow organization and exhaust system facilities during the operation of the inspection workshop, and solve the problem of the accumulation of harmful gases such as ozone and nitrogen oxides in the workshop.Methods:In May 2023, computational fluid dynamics (CFD) technology was used to numerically simulate the diffusion of ozone and nitrogen oxides generated by industrial radiographic inspection operations, and the comparative detection method was used to analyze the ozone and nitrogen oxides concentrations before and after the renovation of the ventilation system of the inspection workshop.Results:After the renovation of ventilation system, the average concentration of ozone in the inspection workshop decreased from 0.81 mg/m 3 to 0.03 mg/m 3, and the average concentration of nitrogen oxides decreased from 0.42 mg/m 3 to 0.01 mg/m 3, and the differences were statistically significant ( t=20.51, 10.38, P<0.001) . Conclusion:The ventilation facilities of the inspection workshop are set up in the airflow organization mode of sending up and down the exhaust, and the ventilation pipes are scientifically designed through the calculation of ventilation hydraulic balance, which can effectively control the concentration of harmful gases in the inspection workshop.

Objective:To investigate the reasonable airflow organization and exhaust system facilities during the operation of the inspection workshop, and solve the problem of the accumulation of harmful gases such as ozone and nitrogen oxides in the workshop.Methods:In May 2023, computational fluid dynamics (CFD) technology was used to numerically simulate the diffusion of ozone and nitrogen oxides generated by industrial radiographic inspection operations, and the comparative detection method was used to analyze the ozone and nitrogen oxides concentrations before and after the renovation of the ventilation system of the inspection workshop.Results:After the renovation of ventilation system, the average concentration of ozone in the inspection workshop decreased from 0.81 mg/m 3 to 0.03 mg/m 3, and the average concentration of nitrogen oxides decreased from 0.42 mg/m 3 to 0.01 mg/m 3, and the differences were statistically significant ( t=20.51, 10.38, P<0.001) . Conclusion:The ventilation facilities of the inspection workshop are set up in the airflow organization mode of sending up and down the exhaust, and the ventilation pipes are scientifically designed through the calculation of ventilation hydraulic balance, which can effectively control the concentration of harmful gases in the inspection workshop.

Objective The aim of this study was to explore the role and mechanism of ferroptosis in SiO2-induced cardiac injury using a mouse model. Methods Male C57BL/6 mice were intratracheally instilled with SiO2 to create a silicosis model.Ferrostatin-1(Fer-1)and deferoxamine(DFO)were used to suppress ferroptosis.Serum biomarkers,oxidative stress markers,histopathology,iron content,and the expression of ferroptosis-related proteins were assessed. Results SiO2 altered serum cardiac injury biomarkers,oxidative stress,iron accumulation,and ferroptosis markers in myocardial tissue.Fer-1 and DFO reduced lipid peroxidation and iron overload,and alleviated SiO2-induced mitochondrial damage and myocardial injury.SiO2 inhibited Nuclear factor erythroid 2-related factor 2(Nrf2)and its downstream antioxidant genes,while Fer-1 more potently reactivated Nrf2 compared to DFO. Conclusion Iron overload-induced ferroptosis contributes to SiO2-induced cardiac injury.Targeting ferroptosis by reducing iron accumulation or inhibiting lipid peroxidation protects against SiO2 cardiotoxicity,potentially via modulation of the Nrf2 pathway.