Changes of axial length in primary and secondary school students in Yunnan and associated factors / 中国学校卫生

Objective@#To explore the pattern of change of axial length/curvatrue radius ratio (AL/CR) and associated factors in primary and secondary school students in Yunnan, so as to provide scientific basis and prospective guidance for early myopia intervention and control.@*Methods@#A total of 685 students from grades 2 to 3 and grade 7 in 2 cities/counties in Yunnan Province were selected by multi stage stratified random cluster sampling method in 2020. All the participants were followed up twice with questionnaire of myopia related factors, uncorrected distance visual acuity, and refractive parameter measurement from October,2021 and March,2023,respectivelty. The distribution and change of AL/CR in different classes and groups were analyzed, and the influencing factos of AL/CR cumulative progression were explored using generalized linear model.@*Results@#AL/CR ratio in primary school students was (2.95±0.09) at baseline, increased to (2.99±0.11) at the first follow up and (3.04±0.12) at the second follow up. AL/CR ratio in middle school students(3.08±0.13) at baseline, increased to (3.12±0.15) at the first follow up and (3.15±0.14) at the second follow up. The generalized linear model showed that after controlling for environmental factors, ethnicity ( β =-0.017) , cumulative progression of the SE ( β =-0.027) influenced the changes of AL/CR ratio among the primary school students, whereas the changes of AL/CR ratio were associated with baseline AL ( β =-0.005), baseline corneal curvatrue radius ( β =0.032) and cumulative progression of SE( β =-0.035) among middle school students ( P <0.05).@*Conclusions@#The AL/CR ratio of primary and secondary school students in Yunnan can be used to judge different refractive status types, but its variation is not only related to SE progression, but also affected by different ethnic groups and baseline ocular biological parameters. so the value of AL/CR application in assessing the progression of myopia needs to be further confirmed.

Discriminante analysis of risk factors Nomograms of myopia in children and adolescents in Yunnan Province / 中国学校卫生

Objective@#To explore the related factors of myopia among children and adolescents in Yunnan Province, and to predict and evaluate the influencing factors, so as to provide a scientific theoretical basis for the prevention and control of myopia.@*Methods@#From March 9 to 14, 2023, 848 students from 6 primary and secondary schools in Dali and Lijiang of Yunnan Province were selected by multi stage stratified random cluster sampling method for visual acuity detection and questionnaire survey on myopia related factors. Multivariate Logistic regression analysis was used to establish a Nomogram prediction model for the selected influencing factors.@*Results@#The overall myopia rate of the respondents was 68.3%, the myopia rate of boys (63.4%) was lower than that of girls (72.9%), and the myopia rate of primary school students (46.7%) was lower than that of junior high school students (81.1%), and the difference was statistically significant（ χ 2=8.71, 108.07, P <0.05). Daily eye exercises, activities outside the teaching building during recess, having daily sleep time of 7-9 and >9 h, having both parents without myopia were negatively correlated with the occurrence of myopia in children and adolescents in Yunnan Province ( OR=0.64, 0.63, 0.56, 0.28, 0.48, P < 0.05 ). The reading and writing time after school ≥3 h per day and parents unrestricted time to play video games were positively correlated with myopia ( OR=1.94, 1.78, P <0.05). Based on the influencing factors, a Nomogram prediction model was established to quantitatively evaluate the risk of myopia. The results showed that greater risk for myopia was associated with sleep duration, parental history of myopia, and the time spent reading and writing after school every day.@*Conclusion@#Both genetic factors and environmental factors are related to myopia in children and adolescents. The prediction model of nomogram is beneficial for screening high risk factors of myopia and taking corresponding prevention and treatment measures.

Characterization of the glucocorticoid receptor of large yellow croaker (Larimichthys crocea) and its expression in response to salinity and immune stressors.

Glucocorticoids are steroidal hormones critical to stress responses in vertebrates. To gain further insight into the role of the glucocorticoid receptor (GR) in acute stress responses in teleost fish, the relevant cDNA of large yellow croaker (Larimichthys crocea; LcGR) was cloned using the rapid amplification of cDNA ends (RACE) technique. Multiple alignment of the amino acids (aa) of LcGR and the GR of other teleosts indicated LcGR contained four commonly conserved domains and lacked the 9-aa insert seen in GR1. Phylogenetic analysis of the amino acid sequence revealed that LcGR grouped most closely with the GR2 of other teleosts and can therefore be considered a GR2 subtype. In healthy L. crocea, Lcgr mRNA was found to be expressed at high levels in the gill, brain, and muscle tissue, expressed at intermediate levels in heart and stomach tissue, and expressed at low levels in the kidney, intestine, head kidney, liver, and spleen tissue. The response of L. crocea to acute low-salinity stress was tested, with a significant increase in plasma cortisol concentration after 3 h, peaking after 6 h, and gradually returning to base levels. Regarding changes of Lcgr expression in different body tissues under the stress, there was up-regulation of the Lcgr transcript in the brain, liver, and gill tissues, but not in muscle tissue. Responses to pathogen mimics were also tested. Injection with lipopolysaccharide resulted in Lcgr expression, with an increase-decrease-increase trend in the head kidney. In contrast, a down-regulation of Lcgr expression in the head kidney was observed throughout the experimental period upon injection of polyinosinic:polycytidylic acid, revealing different roles of Lcgr for different types of pathogens. The results offer novel insights about the effects of different stressors on GR gene expression in L. crocea, and can facilitate further investigations into stress responses in other mariculture fish species.

[Electroencephalogram spectral power analysis of obstructive sleep apnea syndrome patients before and during continuous positive airway pressure therapy].

OBJECTIVE: To investigate the instant effects of continuous positive airway pressure (CPAP) on EEG spectral power changes in obstructive sleep apnea syndrome (OSAS) patients. METHODS: 26 OSAS patients were included. The diagnosis was made by polysomnography (PSG). The CPAP pressure was titrated during the first night of therapy. During another night in two weeks after the diagnostic study, the patients accepted the whole night CPAP treatment while PSG was monitored. C(3)/A(2) was analyzed by using fast fourier transform (FFT). Spectral edge frequency (SEF), median power frequency (MPF), alpha index, beta index, delta index and theta; index during CPAP therapy were compared with those parameters before treatment. RESULTS: Sleep architecture was improved significantly during therapy. The ratio of slow wave sleep (SWS) deficiency reduced from 19/26 to 10/26 (P = 0.0250). There were more times of REM sleep (1.81 +/- 0.25) vs (2.65 +/- 0.17) (P = 0.023). A significant increase of total SWS time over total sleep time (TST) (2.9 +/- 1.1)% vs (6.0 +/- 1.2)% (P = 0.043) was observed, as well as total REM sleep time over TST (12.0 +/- 1.7)% vs (21.1 +/- 1.6)% (P = 0.001). Total stage I and stage II time over TST reduced greatly [from (85.1 +/- 2.1)% to (73.0 +/- 1.9)% (P = 0.000)]. So did the number of wake after sleep onset [from (12.2 +/- 1.3) to (9.4 +/- 1.0) (P = 0.033). The total number of stage I, stage II decreased from (46.4 +/- 4.2) to (36.7 +/- 2.4), but the difference was not significant (P = 0.051). Spectral analysis of EEG showed a decrease of mean SEF in total sleep period (TSP) (14.4 +/- 0.4) Hz vs (13.6 +/- 0.3) Hz (P = 0.003), stage I (15.4 +/- 0.4) Hz vs (14.8 +/- 0.5) Hz (P = 0.040), stage II (13.7 +/- 0.3) Hz vs (12.8 +/- 0.3) Hz (P = 0.007) and REM sleep (15.0 +/- 0.5) Hz vs (13.8 +/- 0.6) Hz (P = 0.028), as well as 0.018 and 0.047]. delta index was increased in stage II sleep (P = 0.030) but not in other sleep stages. CPAP had no obvious influence on theta; index (P > 0.05). The median of SEF in TSP (14 vs 13) Hz (P = 0.0056), stage I (16 vs 15) Hz (P = 0.04) and stage II (13 vs 13) Hz (P = 0.002). Changes of MPF were not as significant as that of SEF, but mean MPF was decreased during TSP and stage IV. CPAP significantly reduced mean beta index [from (8.4 +/- 0.5)% to (7.5 +/- 0.5)% (P = 0.012)] in total sleep period as well as in stage I, II, III and IV sleep (P < 0.015). alpha index in TSP, stage III and IV sleep was decreased significantly (P = 0.045, 0.018 and 0.047 respectively). delta index was increased in stage II sleep (P = 0.030) but not in other sleep stages. CPAP had no obvious influence on theta; index (P > 0.05). CONCLUSIONS: CPAP has an acute effect in improving the sleep architecture and EEG power spectrum. The SEF, beta index and alpha index are more sensitive than MPF, delta index and theta; index to CPAP therapy. These changes may be related to the recovery of cerebral function in OSAS patients after CPAP therapy. More studies need to be conducted to investigate how these changes happen and their relation to daytime cerebral function.