Objective: To understand the microclimate in primary and secondary school classrooms for the study period during the winter heating season, so as to provide a reference for the revision and improvement of relevant health standards. Methods: In December 2024, stratified random sampling was used to select 30 primary and secondary schools and 180 classrooms from the northern regions with centralized heating (Liaoning Province, Tianjin City) and the southern regions without centralized heating (Shanghai City, Anhui Province, and Jiangxi Province). Indoor temperature, relative humidity, wind speed, CO 2 and other indicators were measured on site. Variance analysis, t-test, Mann-Whitney U test and Kruskal-Wallis H test were used to analyze the differences in the microclimate of classrooms among regions and urban and rural differences. Results: The average temperature in the middle of the classrooms tested on site was (16.47±4.72)℃, and the variance analysis showed that the difference between the regions was statistically significant ( F=27.80, P <0.01). Among them, Tianjin had the highest average temperature of (20.43± 2.12 )℃, followed by Liaoning (19.03±2.23)℃, Shanghai (15.33±5.32)℃, Anhui (12.79±1.74)℃, and Jiangxi (11.69± 1.68 )℃. Horizontal temperature difference was 0.90 (0.50, 1.60)℃, the vertical temperature difference was 0.20 (0.10,0.60)℃, the average relative humidity was (44.39±16.16)%, the wind speed was 0.03(0.01,0.11)m/s, and the differences among different provinces and cities were statistically significant ( H/F =40.62, 82.69, 95.06, 55.28, all P <0.01). The average CO 2 volume concentration in urban areas of Tianjin, Liaoning, and Shanghai was 0.21(0.16,0.30)%, and there was no statistically significant difference ( H=4.65, P =0.10). There were grade differences in relative humidity ( F =3.71, 6.21) and CO 2 ( H =14.72, 12.92) in the north and the south (all P <0.05). In addition, the temperature, relative humidity, wind speed and CO 2 in the middle of the classroom were 42.8%, 67.8%, 100.0% and 22.2% respectively. Conclusions The temperature in the middle of the classroom in the non centralized heating area is lower than the standard, the relative humidity of classroom in the centralized heating area is lower than the standard，and the CO 2 in the classroom in winter is lower than the standard. It is recommended to install heating facilities in schools with low temperatures to increase the temperature and increase the frequency of ventilation in classrooms or adopt mechanical ventilation strategies to reduce CO 2 volume concentration.

BACKGROUND:The decreased postural control ability due to mild cognitive impairment in elderly people leads to the increased risk of falls.Dual-task is the primary research paradigm for evaluating the relationship between cognition and postural control in the scenes close to real life.The sample entropy of the plantar center of pressure(COP)displacement during standing can represent the complexity of postural control. OBJECTIVE:Based on the COP displacement sample entropy,to analyze the differences in postural stability characteristics and control strategies between older adults with mild cognitive impairment and cognitively normal older adults during the dual-task with postural control and spatial working memory,aiming to explore the impact of cognitive impairment on the postural control ability during standing. METHODS:Sixteen older adults with mild cognitive impairment and 17 cognitively normal older adults were eligible and selected for the study.They completed five test tasks,including spatial working memory,double-feet balance stance,Romberg stance,double-feet balance stance-spatial working memory dual-task,and Romberg stance-spatial working memory dual-task,with three valid completions of each task.The plantar COP data were collected by the Kistler 3D force platform.The indicators included cognitive behavior(cognitive score and reaction time)and kinematic indexes(COP displacement and sample entropy). RESULTS AND CONCLUSION:The older adults with mild cognitive impairment performed the spatial working memory task with the greatest cognitive score and the shortest reaction time,the double-feet balance stance-spatial working memory dual-task with moderate cognitive score and reaction time,and the Romberg stance-spatial working memory dual-task with the smallest cognitive score and the longest reaction time,where the differences were significant among the tasks(P<0.05).In the older adults with mild cognitive impairment,the anterior-posterior and medial-lateral COP displacements were significantly greater,and their sample entropy values were significantly smaller in the double-feet balance stance-spatial working memory dual-task and Romberg stance-spatial working memory dual-task than in the double-feet balance stance and Romberg stance tasks(P<0.05).In the spatial working memory task,there were no significant differences in cognitive score and reaction time between the both groups(P>0.05);however,in the double-feet balance stance-spatial working memory dual-task and Romberg stance-spatial working memory dual-task,cognitive scores were significantly smaller and reaction times were longer in the older adults with mild cognitive impairment compared with the cognitively normal older adults(P<0.05).In the double-feet balance stance-spatial working memory dual-task and Romberg stance-spatial working memory dual-task,the older adults with mild cognitive impairment exhibited significantly greater anterior-posterior and medial-lateral COP displacements and significantly smaller sample entropy values compared with the cognitively normal older adults(P<0.05).All findings indicate that compared with cognitively normal older adults,older adults with mild cognitive impairment exhibit smaller complexity,poorer systematic adaption and decreased automatic regulation of the postural control during performing the dual-tasks,who are more susceptible to spatial working memory interference,leading to the increased risk of falls.

BACKGROUND:The imbalance between bone resorption and bone formation in microgravity environments leads to significant bone loss in astronauts.Current research indicates that bone loss under microgravity conditions is the result of the combined effects of various cells,tissues,and systems. OBJECTIVE:To review different biological effects of microgravity on various cells,tissues,or systems,and summarize the mechanisms by which microgravity leads to the development of osteoporosis. METHODS:Databases such as PubMed,Web of Science,and the Cochrane Database were searched for relevant literature from 2000 to 2023.The inclusion criteria were all articles related to tissue engineering studies and basic research on osteoporosis caused by microgravity.Ultimately,85 articles were included for review. RESULTS AND CONCLUSION:(1)In microgravity environment,bone marrow mesenchymal stem cells tend to differentiate more into adipocytes rather than osteoblasts,and hematopoietic stem cells in this environment are more inclined to differentiate into osteoclasts,reducing differentiation into the erythroid lineage.At the same time,microgravity inhibits the proliferation and differentiation of osteoblasts,promotes apoptosis of osteoblasts,alters cell morphology,and reduces the mineralization capacity of osteoblasts.Microgravity significantly increases the number and activity of osteoclasts.Microgravity also hinders the differentiation of osteoblasts into osteocytes and promotes the apoptosis of osteocytes.(2)In a microgravity environment,the body experiences changes such as skeletal muscle atrophy,microvascular remodeling,bone microcirculation disorders,and endocrine disruption.These changes lead to mechanical unloading in the bone microenvironment,insufficient blood perfusion,and calcium cycle disorders,which significantly impact the development of osteoporosis.(3)At present,the mechanism by which microgravity causes osteoporosis is relatively complex.A deeper study of these physiological mechanisms is crucial to ensuring the health of astronauts during long-term space missions,and provides a theoretical basis for the prevention and treatment of osteoporosis.

Background Hypertension is one of the chronic diseases with the highest prevalence in China, and a history of hypertension may potentially exacerbate hearing loss. Investigating the association between long-term blood pressure trends and hearing thresholds could contribute to hearing protection efforts for occupationally noise-exposed populations. Objective By investigating hearing thresholds and blood pressure levels among occupationally noise-exposed workers in an urban rail transit enterprise, and conducting a comprehensive analysis of the association between long-term blood pressure changes and hearing thresholds, to provide data references for health management strategies targeting occupationally noise-exposed workers. Methods Workers exposed to occupational noise at a rail transit enterprise were enrolled as study subjects and underwent pure-tone audiometry. Group-based trajectory modeling was employed to identify blood pressure trajectories. Categorical data were compared using chi-square tests, while normally distributed continuous variables were analyzed via t-tests and analysis of variance (ANOVA). Generalized linear mixed models (GLMMs) were subsequently applied toexamine associations between these trajectory groups and high-frequency hearing thresholds. Results Among 2 002 occupationally noise-exposed workers, the median (P₂₅, P₇₅) age was 32 (28, 35) years, with a median (P₂₅, P₇₅) working tenure of 7 (3, 10) years. In 2019, the positive hypertension rate was 9.04%, with a mean systolic blood pressure (SBP) of (122.97±11.60) mmHg and a mean diastolic blood pressure (DBP) of (76.37±9.02) mmHg. The hearing loss prevalence was 10.1%, showing bilateral high-frequency average hearing thresholds of (17.18±8.71) dB and speech-frequency average thresholds of (13.79±3.46) dB. Three distinct trajectory groups were identified for both SBP and DBP. Compared with other trajectory groups, the high-stable DBP group exhibited significantly higher hearing loss prevalence (χ²=6.34, P=0.042) and elevated high-frequency hearing thresholds (all Ps<0.05). Specifically, within the 30-39 age subgroup, the moderate-stable DBP group demonstrated 1.96 dB lower high-frequency thresholds than the high-stable group [β(95%CI): −1.96 (−3.61, −0.32), P=0.020]. Conclusion Among occupationally noise-exposed workers in a municipal rail transit enterprise, DBP trajectories demonstrated a positive association with high-frequency hearing thresholds. Notably, in young and middle-aged occupationally noise-exposed populations, DBP may exert a more critical influence than SBP on the progression of hearing loss.

ObjectiveTo evaluate the pharmacological effect of Buzhong Yiqitang on brain development in offspring of rats with subclinical hypothyroidism （SCH） during pregnancy and explore its potential mechanism. MethodsForty-eight SPF female SD rats were divided into sham operation group （n=8） and model group （n=40）. The rat model of subclinical hypothyroidism （SCH） was constructed by total thyroidectomy combined with postoperative subcutaneous injection of levothyroxine （L-T₄）. The modeled rats were randomly allocated into model， low-， medium-， and high-dose （5.58， 11.16， 22.32 g∙kg^-1， respectively） Buzhong Yiqitang， and euthyrox （4.5×10^-6 g∙kg^-1） groups， with 8 rats in each group. These rats were co-housed with normal male rats for mating. Drug administration started 2 weeks before pregnancy and continued until delivery. Hematoxylin-eosin staining and Golgi-cox staining were used to observe pathological changes in the hippocampal tissue of offspring rats. Western blot was employed to detect the effects of Buzhong Yiqitang on the protein levels of cytochrome C oxidase subunitⅠ （COX）Ⅰ and COXⅣ in the hippocampal tissue of offspring rats. A colorimetric method was used to measure the mitochondrial adenosine triphosphate （ATP） content in the hippocampal tissue of offspring rats. For in vitro experiments， a hydrogen peroxide （H₂O₂）-induced oxidative damage model was established with rat pheochromocytoma cells （PC12）. Interventions included the DNA methyltransferase inhibitor （SGI-1027）， Buzhong Yiqitang-medicated serum， and euthyrox-medicated serum. The cell counting kit-8 （CCK-8） assay was used to examine the effect of Buzhong Yiqitang on cell proliferation. Immunofluorescence staining was performed to evaluate the effect on tubulin beta 3 class Ⅲ （TUBB3） in PC12 cells. Western blot was employed to assess the effects on the protein levels of DNA methyltransferases （TETs and DNMTs） in PC12 cells. The fluorescent probe 2′，7′-dichlorodihydrofluorescein diacetate （DCFH-DA）， luciferase assay， and JC-1 staining were employed to assess the effects of Buzhong Yiqitang on the levels of reactive oxygen species （ROS） and ATP and the mitochondrial membrane potential in PC12 cells. ResultsCompared with the sham group， the model group showed a reduction in the number of hippocampal neurons， incomplete pyramidal cell bodies， loose arrangement， shortened average dendrite length， decreased dendritic complexity and dendritic spine density， and reduced expression levels of COXⅠ and COXⅣ and content of ATP in the brain tissue （P<0.05， P<0.01）. Compared with the model group， after administration of Buzhong Yiqitang and euthyrox， hippocampal neurons exhibited regular arrangement， complete morphology， extended dendrite， increased dendritic complexity and dendritic spine density， and restored expression levels of COXⅠ and COXⅣ and content of ATP （P<0.05， P<0.01）， with the medium-dose Buzhong Yiqitang group showing the best therapeutic effect. In the PC12 cell model of oxidative damage， Buzhong Yiqitang increased the cell viability （P<0.01）， enhanced neuronal differentiation， down-regulated the expression levels of DNMTs （P<0.05）， up-regulated the expression levels of TETs （P<0.05）， decreased the ROS content （P<0.01）， and restored the ATP content and mitochondrial membrane potential （P<0.01）. ConclusionBuzhong Yiqitang protects brain development in offspring of pregnant rats with SCH. It mainly acts on the oxidative stress and mitochondrial dysfunction resulted from abnormal mtDNA methylation， with DNMTs and TETs as the key proteins for its effects.

Objective: To explore the iodine nutrition status of children in Wuhan from 2019 to 2023, and to evaluate the effect of iodine deficiency disorders control in focus groups in Wuhan, so as to provide a basis for consolidating elimination of iodine deficiency disorders. Methods: A total of 13 000 non boarding primary school students aged 8-10 were selected from 13 districts of Wuhan by stratified random sampling method.Household salt samples were collected to measure salt iodine content, random urine samples were analyzed for urinary iodine concentration. And B ultrasound was used to measure thyroid volume in students. The median of salt iodine, coverage rate of iodized salt, consumption rate of qualified iodized salt, median of urinary iodine, and the goiter rate were calculated. And Mann-Whitney U- test, Kruskal-Wallis H- test and Chi-square test were applied to compare between groups. Chi-square trend test was used to analyze the changing trends of coverage rate of iodized salt, consumption rate of qualified iodized salt and goiter rate among children in Wuhan. Results: The median of iodine content of children s household salt was 23.8 (21.7, 26.1) mg/kg, and the coverage rate of iodized salt was 98.7%, and the consumption rate of qualified iodized salt was 94.5 %. The consumption rates of qualified iodized salt showed an overall upward trend from 2019 to 2023 ( χ 2 trend =5.57， P <0.05). The median of urinary iodine of children was 220.1 (136.7, 326.0) μg/L,and boys had higher median of urinary iodine than girls [228.3(143.2, 336.0),210.2(129.1, 315.7) μg/L] ( Z =6.60, P <0.01). The median of urinary iodine of children in suburbs was higher than those in urban areas [236.3 (150.7, 342.2) , 207.1 (124.5, 309.8) μg/L]( Z =11.00, P <0.01). A total of 4 600 children were examined for thyroid volume, and the range of goiter rates were 1.1% to 3.4%, with an average goiter rate of 2.5%, which showed an overall downward trend from 2019 to 2023 ( χ 2 trend =5.11, P <0.05). Conclusions The iodine nutrition is sufficient and iodine nutrition status is good among children in Wuhan. It should continue to carry out monitoring and evaluation of children s iodine nutrition, guide the public to supplement iodine scientifically,so as to maintain the appropriate level of iodine for children.

Objective: This study aims to explore the association between oral lichen planus (OLP) and Hashimoto’s thyroiditis (HT) and its anti-thyroid antibodies to provide clinical evidence for thyroid disease screening in patients with OLP. Methods: This study was approved by the institutional ethics committee. A total of 125 clinically and histopathologically confirmed patients with OLP were enrolled as the case group, and they were matched with 125 non-OLP controls based on sex and age. Demographic data (gender, age, lesion type, and disease duration) were collected from both groups. Serum levels of thyroid peroxidase antibodies (TPOAb) and thyroglobulin antibodies (TgAb) were measured to analyze their associations with sex, age, lesion type, and disease duration in patients with OLP. Result: The prevalence of HT in patients with OLP was 31.20%, significantly higher than that in the control group (9.60%) (χ2=18.504, P<0.001). The prevalence of HT in female patients with OLP (39.13%) was significantly higher than that in male patients (9.09%)（χ2=10.93，P<0.001）. The positivity rate of thyroid peroxidase antibodies (TPOAb) in patients with OLP (17.6%) was significantly higher than in the control group (4.0%) (χ2=10.989, P<0.001). The TPOAb positivity rate was significantly higher in female patients (22.83%) than in male patients (3.03%) (χ2=5.210, P=0.014). There was no statistically significant difference in the positivity rate of TgAb between patients with OLP (7.2%) and the control group (3.2%) (P>0.05). Patients with erosive lesions had a significantly higher TPOAb positivity rate (25.0%, 17/68) compared to those with non-erosive lesions (8.77%, 5/57), and the difference was statistically significant (χ2=4.831, P=0.028). Logistic regression analysis revealed that female patients with OLP had an 8.935-fold higher risk of being TPOAb positive compared to males (OR=8.935, 95%CI: 1.134-70.388, P=0.038). Patients with erosive OLP lesions had a 3.199-fold higher risk of TPOAb positivity compared to those with non-erosive lesions (OR=3.199, 95%CI: 1.064-9.618, P=0.038). Conclusion The prevalence of HT is higher in patients with OLP, with higher positivity rates of anti-thyroid antibodies observed in female patients and those with erosive OLP lesions. This suggests that thyroid disease screening should be incorporated into the clinical management of patients with OLP, especially for women and patients who present with erosive lesions.

ObjectiveTo explore quality difference factors of Perillae Caulis based on the contents of multiple chemical components and comprehensively evaluate the quality. MethodsA total of 32 batches of Perillae Caulis samples were collected from 12 producing areas such as Hebei， Anhui and Guangdong， and their diameter range， epidermis color and producing areas were recorded. Total flavonoids， total phenols， volatile oils， 5 active components and 84 volatile components in 32 batches of samples were quantitatively or semi-quantitatively determined by colorimetry， ultra performance liquid chromatography-photodiode array detector（UPLC-PDA） and gas chromatography-mass spectrometry（GC-MS）. Then the differences between the contents of these components were analyzed by principal component analysis（PCA） and non-parametric test. According to the weights of the index components determined by PCA model， entropy weight-technique for order preference by similarity to ideal solution（TOPSIS） model was constructed to evaluate the quality of Perillae Caulis with different characters and origins. ResultsThere were significant differences in the composition of Perillae Caulis with different diameters， epidermis colors and producing areas， and 9 differential components were screened out， including 6 index constituents（total flavonoids， total phenols， caffeic acid， scutellarin， rosmarinic acid and luteolin） and 3 volatile components（caryophyllene oxide， （-）-humulene epoxide Ⅱ， 14-hydroxycaryophyllene）， of which 6 index constituents were higher in samples with small diameter， purple-brown epidermis and southern origin， while the contents of 3 volatile components were higher in samples with large diameter， dark-brown epidermis and northern origin. A significant difference was shown in the model scores of different diameters， epidermis colors and origins（P<0.05）， and the scores of Perillae Caulis with small diameter and purple-brown epidermis from southern area， especially Guangdong， had a high score. ConclusionThere are significant differences in the composition and content of chemical constituents between different diameters， epidermal colors and production areas of Perillae Caulis， samples showing small diameter， owing purple-brown epidermis， and originating from Guangdong were of higher-quality due to their higher content of 8 key indices.

ObjectiveTo explore quality difference factors of Perillae Caulis based on the contents of multiple chemical components and comprehensively evaluate the quality. MethodsA total of 32 batches of Perillae Caulis samples were collected from 12 producing areas such as Hebei， Anhui and Guangdong， and their diameter range， epidermis color and producing areas were recorded. Total flavonoids， total phenols， volatile oils， 5 active components and 84 volatile components in 32 batches of samples were quantitatively or semi-quantitatively determined by colorimetry， ultra performance liquid chromatography-photodiode array detector（UPLC-PDA） and gas chromatography-mass spectrometry（GC-MS）. Then the differences between the contents of these components were analyzed by principal component analysis（PCA） and non-parametric test. According to the weights of the index components determined by PCA model， entropy weight-technique for order preference by similarity to ideal solution（TOPSIS） model was constructed to evaluate the quality of Perillae Caulis with different characters and origins. ResultsThere were significant differences in the composition of Perillae Caulis with different diameters， epidermis colors and producing areas， and 9 differential components were screened out， including 6 index constituents（total flavonoids， total phenols， caffeic acid， scutellarin， rosmarinic acid and luteolin） and 3 volatile components（caryophyllene oxide， （-）-humulene epoxide Ⅱ， 14-hydroxycaryophyllene）， of which 6 index constituents were higher in samples with small diameter， purple-brown epidermis and southern origin， while the contents of 3 volatile components were higher in samples with large diameter， dark-brown epidermis and northern origin. A significant difference was shown in the model scores of different diameters， epidermis colors and origins（P<0.05）， and the scores of Perillae Caulis with small diameter and purple-brown epidermis from southern area， especially Guangdong， had a high score. ConclusionThere are significant differences in the composition and content of chemical constituents between different diameters， epidermal colors and production areas of Perillae Caulis， samples showing small diameter， owing purple-brown epidermis， and originating from Guangdong were of higher-quality due to their higher content of 8 key indices.

Treatment based on meridian differentiation is a characteristic method in clinical acupuncture diagnosis and treatment. Accurately defining and explaining its main content and core concepts is essential for effective clinical guidance. This paper reviews the historical and contemporary understanding, concepts, and primary content of treatment based on meridian differentiation. It proposes a four-step process for clinical application: meridian examination, treatment based on meridian differentiation, acupoint selection, and appropriate treatment methods, with TCM syndrome differentiation applied throughout. Constructing a diagnostic and treatment system which is based on meridian differentiation and suited to clinical acupuncture is significant for enhancing therapeutic efficacy and maximizing the benefits of acupuncture in disease treatment.
Humans ; Meridians ; Acupuncture Therapy/methods* ; Acupuncture Points ; Medicine, Chinese Traditional