AIM: To investigate the effects of hypobaric hypoxia in plateau on tear indexes and related anatomical structures in rabbits.METHODS: A total of 18 healthy New Zealand rabbits were selected and randomly divided into plateau group and control group, with 9 rabbits(18 eyes)in each group. The plateau group was housed in the Simulated Climate Cabin for Special Environment of Northwest of China, simulating hypobaric hypoxia at an altitude of 6 000 m. The control group was housed in a clean animal room with atmospheric pressure and oxygen. Changes in the tear meniscus height and non-invasive tear break-up time were detected by using RHCT-1 corneal topographer dry eye comprehensive analysis system, changes in tear secretion was measured by Schirmer Ⅰ test, before intervention and on the 3, 7 d, 2 and 4 wk. Meanwhile, the changes in tear composition before and after intervention in the plateau environment were analyzed using Raman Spectroscopy. The histopathological changes of the lower lid conjunctiva, cornea, lacrimal gland, and Hardarian gland were observed by hematoxylin-eosin(HE)staining after 4 wk of intervention, and the expression of mucin 5AC(MUC5AC)in conjunctiva was detected by immunohistochemistry.RESULTS: Compared with the control group, Schirmer Ⅰ test, tear meniscus height, first and average non-invasive tear break-up time in the plateau group decreased significantly since 3 d, and the difference was significant with the extension of observation time(P<0.05). The above indexes increased from 2 wk. After 4 wk of intervention, the protein and lipid content of the tear composition of rabbits in the plateau group increased, and the nucleic acid content decreased compared with the pre-intervention period. Compared with the control group, rabbits in the plateau group showed thickening of corneal stromal edema, an increase in the number of conjunctival cup cells, increase in the level of expression of MUC5AC, an increase in the level of expression of MUC5AC, an atrophy and flattening of cytoplasm in lacrimal epithelial cells, an enlargement of glandular lumen, and no obvious destructive changes in the Hardarian glands.CONCLUSION: Acute plateau environment can destroy the homeostasis of rabbit ocular surface, so that the tear secretion and the tear film stability decreases, but within a certain period of time, rabbits undergo compensation with the habituation to the hypobaric hypoxia environment, which can increase the tear secretion to a certain extent and restore the tear film stability.

Objective: Based on physical activity (PA) and sedentary behavior (SB) variables on weekdays and weekends, the study aims to cluster the physical activities inside and outside kindergartens and to explore the cluster characteristics of different children using physical fitness indicators, so as to provide new strategies and methods for early childhood education and health. Methods: From March to June 2019, 291 children aged 3-6 years from 6 kindergartens in Nanchang were recruited by a stratified cluster random sampling method. The ActiGraph GT3X-BT triaxial accelerometer was used to measure and analyze the PA and SB levels inside and outside the kindergarten. A twostep clustering algorithm model was employed for cluster analysis. Physical fitness were measured and evaluated according to the "National Physical Fitness Measurement Standard Manual (Preschool Section)". Differences in physical fitness among different clusters of children were compared, and the cluster characteristics of different children were analyzed. Results: The clustering algorithm model indicated that based on six indicators, including PA and SB inside the kindergarten on weekdays, and PA and SB outside the kindergarten on both weekdays and weekends, children could be divided into three categories:active inside (high PA, low SB inside), active outside (high PA outside), and inactive (low PA, high SB both inside and outside). The average silhouette coefficient of the model was 0.3, indicating good clustering results. Both the active inside and active outside children showed significantly higher PA inside on weekdays, PA outside on weekdays and weekends, daily low intensity physical activity (LPA) and moderate-to-vigorous physical activity (MVPA) than the inactive children ( F=157.91, 80.79 , 95.86, 95.52, 124.74, P <0.05). After adjusting for gender and age, the physical fitness scores of both active outside ( 19.03 ±0.47) and active inside (19.11±0.40) were significantly higher than those of the inactive children (17.94±0.31). Additionally, active inside children (3.91±0.14) also showed significantly better performance in continuous double-leg jumps, compared to inactive children (3.45±0.11) ( P <0.05). Conclusion Children active inside and those active outside perform well in PA. Future research should focus on the proportion of structured and unstructured PA time to enhance the overall physical fitness of children.

Objective:To analyze the external quality control assessment results of urinary iodine, salt iodine and water iodine in iodine deficiency disorders laboratories in Qinghai Province, to evaluate the testing capacity of provincial, municipal and county-level laboratories and the operation of external quality control network, so as to provide quality assurance for consolidating and eliminating iodine deficiency disorders.Methods:In 2021, 1 provincial, 8 municipal, and 43 county-level laboratories in Qinghai Province had participated in the assessment of urinary iodine and salt iodine, while 1 provincial and 8 municipal-level laboratories had participated in the assessment of water iodine. The assessment results were evaluated using the method of reference value ± uncertainty of external quality control samples.Results:All laboratories that participated in the assessment had provided feedback. One provincial-level laboratory passed the assessment of urinary iodine, salt iodine, and water iodine. Among 8 municipal-level laboratories, 2 laboratories failed the urinary iodine assessment, with a pass rate of 6/8; the assessment of salt iodine and water iodine in 8 laboratories were all qualified. Among 43 county-level laboratories, 7 laboratories failed the urinary iodine assessment, with a pass rate of 83.7% (36/43); the assessment of salt iodine in 43 laboratories were all qualified.Conclusions:The external quality control network of iodine deficiency disorders laboratories in Qinghai Province has fully covered all municipal and county-level laboratories. The testing capability of provincial-level laboratory is stable and maintains a high level; the testing quality of some municipal and county-level laboratories is still unstable and needs to be further strengthened.

The cell cycle inhibitor P21 has been implicated in cell senescence and plays an important role in the injury-repair process following lung injury. Pulmonary fibrosis (PF) is a fibrotic lung disorder characterized by cell senescence in lung alveolar epithelial cells. In this study, we report that P21 expression was increased in alveolar epithelial type 2 cells (AEC2s) in a time-dependent manner following multiple bleomycin-induced PF. Repeated injury of AEC2s resulted in telomere shortening and triggered P21-dependent cell senescence. AEC2s with elevated expression of P21 lost their self-renewal and differentiation abilities. In particular, elevated P21 not only induced cell cycle arrest in AEC2s but also bound to P300 and β-catenin and inhibited AEC2 differentiation by disturbing the P300-β-catenin interaction. Meanwhile, senescent AEC2s triggered myofibroblast activation by releasing profibrotic cytokines. Knockdown of P21 restored AEC2-mediated lung alveolar regeneration in mice with chronic PF. The results of our study reveal a mechanism of P21-mediated lung regeneration failure during PF development, which suggests a potential strategy for the treatment of fibrotic lung diseases.

Objective:To verify the revised method of cerium sulfate catalytic spectrophotometry for iodide index of "Standard Examination Methods for Drinking Water-Nonmetal Parameters" (GB/T 5750.5-2006).Methods:From July to September 2019, the Laboratory of Department for Endemic Disease Prevention and Control of Qinghai Institute for Disease Prevention and Control verified the revised method (determination of iodide in drinking water by cerium sulfate catalytic spectrophotometry) of cerium sulfate catalytic spectrophotometry (hereinafter referred to as original method) in "Standard Examination Methods for Drinking Water-Nonmetal Parameters" (GB/T 5750.5-2006). The revised method was verified according to the requirements of "Standard Examination Methods for Drinking Water-Water Analysis Quality Control" (GB/T 5750.3-2006), including standard curve, detection limit, precision, accuracy and actual sample determination.Results:The linear range of the revised method was 0 - 20.0 μg/L, the correlation coefficient was - 0.999 4 - 0.999 8, and the detection limit was 0.231 μg/L. The relative standard deviation ( RSD) of low, medium and high iodine water samples of 6 times detection ranged from 1.4% to 9.6%, and the recoveries of low and medium water samples ranged from 89.0% to 108.0%. The detection results of national first-class reference materials for iodine composition analysis in water were within the range of standard value ± uncertainty. There was no significant difference in the test of results of 12 tap water samples between the revised method and the original standard method ( t = - 0.075, P > 0.05). Conclusion:The revised method has a good linear relationship of standard curve, high precision and accuracy, and good reproducibility, is simple and easy to operate, and is suitable for promotion and application.

Objective: To understand the present situation of physical activity and its influencing factors, and to provide a reference for improving the level of physical activity and making the intervention measures. Methods: The method of random stratification was used to select 4 740 pre school children aged 3-6 from 17 kindergartens in 12 counties and districts of Nanchang City, The questionnaire of physical activities of young children and the questionnaire of parents of physical activities of young children were applied to conduct a survey. Results: Compared with weekday PA and MVPA, preschool children’s weekends decreased, SB increased. The differences in PA, MVPA and SB on weekdays and weekends were statistically significant( P <0.01). The proportion of PA and MVPA reaching the recommended amount during the working day of preschool children were 44.9%-59.2%, 45.4%- 61.7%.The proportion reaching the recommended amount of PA and MVPA on weekends were 24.7%-27.8%, 24.5%-29.9%, and the proportion reaching the recommended amount on weekdays was higher than that on weekends. Conclusion There is still gap between actual amount of physical activity and the recommended amount. There are different modes of activity on weekdays and weekends, and weekends are the least active periods. Parents and teachers should pay enough attention to the establishment of "social campus family" model to improve the lack of physical activity of preschool children.

Objective: To explore the prevalence of body weight control behaviors (BWCB) among middle school students in Jiangsu province. Methods: The database was established part from the surveillance of adolescent common disease and health related factors in Jiangsu province in 2017 and analysis were carried out to describe the prevalence rates of four basic BWCB and their comorbidity. Results: Among 18 855 investigators, 75.8% middle school students reported having taken at least one kind of BWCB within 30 days before investigation, the report rates of BWCB of middle school students among male and female were 77.3% and 74.3%(P<0.01), showed decreasing tendency from grade 1 of junior middle school to grade 3 of senior middle school (Kendall’s tau-c=-0.10, P<0.01), those of malnutrition, normal body weight, overweight and obesity were 57.2%, 72.8%, 83.8%, 86.7% respectively and showed increasing tendency(Kendall’s tau-c=0.13, P<0.01). Reported rate of Changing diet structure, physical exercise, reducing diet and taking slimming drug prevalence were 58.7%, 61.0%, 17.9%, 2.6%, orderly. There are 15 combinations of BWCB based on those 4 kinds of behavior. In the highest five types list ,changing diet structure & physical exercise (35.2%) was the most common type, and followed by physical exercise(13.0%), Changing diet structure(9.2%), Changing diet structure & physical exercise & reducing diet(8.6%), Changing diet structure & physical exercise & reducing diet(3.4%), others 6.5%. The proportions of top five kinds of BWCB among middle school students taken BWCB were 46.4%, 17.1%, 12.2%, 11.3%, 4.5%, respectively, accounting for 91.5%. The probabilities of different types of BWCB were similar between urban and town(χ2=9.13, P=0.10), different among sex(χ2=351.17, P<0.01), districts(χ2=140.20, P<0.01), school type and nutrition status(χ2=343.95, 309.62, P<0.01). Conclusion Some overweight or obesity students report on control body weight, while some report taking medicine and reducing diet behavior. Health education on healthy body weight should be implemented for middle school students to cultivate healthy body image so as to keep healthy body weight.

Mycophenolic acid (MPA, ) and its derivatives are first-line immunosuppressants used in organ transplantation and for treating autoimmune diseases. Despite chemical synthetic achievements, the biosynthetic formation of a seven-carbon carboxylic acid pharmacophore side chain of , especially the processes involving the cleavage of the prenyl side chain between DHMP () and DMMPA (), remains unknown. In this work, we identified a membrane-bound prenyltransferase, PgMpaA, that transfers FPP to to yield FDHMP (). Compound undergoes the first cleavage step a new globin-like enzyme PgMpaB to form a cryptic intermediate . Heterologous expression of genes in demonstrates that the second cleavage step (from to ) of is a cluster-independent process . Our results, especially the discovery of the broad tolerance of substrates recognized by PgMpaB, set up a strategy for the formation of "pseudo-isopentenyl" natural products using fungal globin-like enzymes.

ObjectiveTo discuss the effects of targeted nursing intervention on pregnancy outcome and neonatal weight in patients with gestational diabetes mellitus (GDM). MethodsTotally 108 GDM patients treated in our hospital from July 2017 to February 2019 were selected and divided into intervention (n=54) and control (n=54) groups according to the random number table. Patients in the control group received conventional nursing care, while patients in the intervention group received targeted care on this basis. Patient＇s blood glucose level, pregnancy outcome, neonatal weight and satisfaction with nursing before and after nursing care were compared between the two groups. ResultsThere was no statistically significant difference in blood glucose levels between the two groups before nursing intervention (P＞0.05). Fasting blood glucose, 2 h postprandial blood glucose and glycosylated hemoglobin levels were lower after nursing intervention in both groups. The levels of the intervention group were even lower than those of the control group, and there were statistically significant differences between the two groups (P＜ 0.05). The incidence of malignant pregnancy outcome and neonatal complications of the intervention group were lower than those of the control group after nursing intervention, and patient＇s satisfaction with nursing was higher in the intervention group than in the control group, and there were statistically significant differences between the two groups (P＜ 0.05). ConclusionsTargeted nursing intervention can effectively reduce blood glucose levels of GDM patients and the incidence rate of adverse maternal and neonatal outcome, and improve patient＇s satisfaction, which is worth promoting in clinical practice.

Objective To investigate the positive rates and susceptibility of Ureaplasma urealyticum(Uu) and Mycoplasma hominis(Mh) in urogenital mycoplasma infection under three years.Methods Culture,identification and susceptibility test were performed on 4 414 specimens collected from suspected patients with mycoplasma infection by using Antu mycoplasma kits.Results In the 4 414 patients,2 295 cases with mycoplasma infection were detected and the positive rate was 51.99％.The infection rates of Uu and Mh respectively were 40.69％ and 2.08％,and the both infection rate was 9.22％.Antibiotic sensitive rates of josamycin(JOX),doxycycline(DOX),clarithromycin(CLA),gatifloxacin(GAT) and erythromycin(ERY) were 96.03％,95.51 ％,78.69 ％％,77.21 ％ and 72.55 ％.Drug resistant rates of roxithromycin(RXT),thiamphenicol (THI),clindamycin (CLI) and clarithromycin(CLA) were 16.90％,22.27％,41.96％ and 17.60％.Conclusion Uu is the predominant mycoplasma in urogenital tract infection in the study.DOX,JOS,GAT and ERY can be chosen as the fist line drugs for the treatment of urogenital tract infection.RXT,THI,CLI and CLA with high drug resistant rates are not recommended to be used.