AIM:To investigate the effect of peripheral defocus design rigid gas permeable contact lenses(defocus RGPCL)in controlling myopia progression in children aged 6-12 y with high myopia, and to compare the outcomes with traditional single-vision RGPCL and single-vision spectacles.METHODS:This prospective cohort study enrolled children aged 6-12 y with high myopia who visited the Ophthalmology and Optometry Center of Xi'an No.1 Hospital between January 2022 and January 2023. Based on parental preference, participants were divided into three groups: defocused RGPCL group, single-vision RGPCL group, and single-vision spectacles group. The axial length(AL)and cycloplegic spherical equivalent(SE)refraction were compared at baseline, 0.5, 1, 1.5, and 2 y after lens wear. Additionally, AL and SE delay rates were calculated for each group.RESULTS: This study enrolled a total of 90 children with high myopia(180 eyes), with no participants lost to follow-up. Participants were allocated into three groups based on parental preference. Thirty children(60 eyes)were assigned to the peripheral defocus RGPCL group, consisting of 12 boys and 18 girls with a mean age of 9.96±1.56 y; 30 children(60 eyes)to the single-vision RGPCL group, including 15 boys and 15 girls with a mean age of 9.40±1.52 y; and 30 children(60 eyes)to the single-vision spectacles group, with 14 boys and 16 girls and a mean age of 9.80±1.37 y. At 0.5, 1, 1.5, and 2 y lens fitting, AL and SE increased significantly in all three groups(all P<0.05), with the growth rates in the defocused RGPCL group being significantly lower than those in the single-vision RGPCL and single-vision spectacles groups(all P<0.05). At 2 y lens fitting, the AL elongation was 0.22±0.24 mm and the mean SE progression was 0.70±0.70 D in the peripheral defocus RGPCL group; 0.49±0.38 mm and 1.34±0.60 D in the single-vision RGPCL group; and 0.50±0.21 mm and 1.72±0.47 D in the single-vision spectacles group. Using the single-vision spectacles group as the control, the AL delay rate and SE delay rate at 2 y lens fitting were 56.0% and 59.3%, respectively, in the defocused RGPCL group.CONCLUSION:For children with high myopia aged 6-12 y, defocus RGPCLs can effectively and significantly delay AL elongation and SE progression, demonstrating markedly superior control efficacy compared to single-vision RGPCL or single-vision spectacles. Defocused RGPCL can serve as an effective optical intervention for high myopia children.

With the extensive application of low-dose ionizing radiation (LDIR) in medicine, aerospace, and other fields, the potential for exposure among the general population and occupationally exposed workers has increased, raising growing public health concerns regarding its possible effects on cognitive function. Current occupational and environmental radiation protection frameworks are primarily established based on cancer risk estimates derived from epidemiological evidence under high-dose exposure and extrapolation across dose ranges, whereas evidence regarding non-cancer outcomes, including potential cognitive effects of LDIR, remains limited and inconsistent, and the underlying neurobiological mechanisms have not been fully elucidated. This review summarized recent advances in research on the effects of LDIR on cognitive function and the associated neural mechanisms. Existing evidence indicates that LDIR may adversely affect cognitive domains including spatial memory and object recognition memory under certain exposure conditions, with potential mechanisms involving alterations in synaptic plasticity, microglia activation, neurodevelopmental processes, epigenetic regulation, and DNA damage and repair pathways. In contrast, studies using pathological models, including stroke and neurodegenerative diseases, have reported potential protective effects of LDIR, which may be mediated by attenuation of oxidative stress, neuroinflammation and activation of endogenous repair pathways. This indicates that LDIR has both damaging and protective effects on brain function; a deeper understanding of its patterns and mechanisms can provide a scientific basis for establishing occupational and environmental radiation protection standards. Furthermore, re-examining the LDIR risk assessment system may also offer new insights into exploring the therapeutic potential of LDIR for brain diseases.

AIM: To compare the progression of myopia in children wearing orthokeratology lenses combined with low-concentration atropine before and after drug withdrawal, to determine the rebound effect of drug withdrawal in orthokeratology lens wearers, and to analyze its causes based on changes in pupil diameter.METHODS:A prospective case-control study was conducted to collect 80 children with myopia who were treated with orthokeratology lenses combined with 0.01% atropine ophthalmic gel at the Xi'an No.1 Hospital from January to June 2022. One year later, they were divided into a drug withdrawal group(Group A, 40 cases)and a continuous medication group(Group B, 40 cases)based on whether they stopped taking the medication. The progression of myopia before and after drug withdrawal was observed by analyzing changes in axial length(AL)and spherical equivalent(SE)in the group A within 1 a before and after drug withdrawal. The changes in AL, pupil diameter(PD), and SE were compared between the group A and group B within 2 a, and the correlation between PD and AL growth was analyzed.RESULTS:In the group A, the AL increased by 0.17±0.23 and 0.29±0.18 mm at 0.5 and 1 a after drug withdrawal, respectively, which were both greater than before drug withdrawal(t=5.318, 2.983, both P<0.001). There was no statistically significant difference in SE growth between the two time points(P>0.05). There were no statistically significant differences in AL and PD between the group A and group B at baseline, 0.5 and 1 a during combined medication(all P>0.05). At 1.5 a, the AL growth of the group A was greater than that of the group B(0.32±0.27 mm vs 0.26±0.20 mm, t=7.363, P<0.001), and the PD was smaller than that of the group B(3.60±1.25 mm vs 4.12±1.92 mm, t=-7.541, P<0.001). At 2 a, the AL growth of the group A was greater than that of the group B(0.44±0.18 mm vs 0.32±0.14 mm, t=5.709, P<0.001), and the PD was smaller than that of the group B(3.67±1.31 mm vs 4.02±1.67 mm, t=-4.281, P<0.001). Correlation analysis showed a negative correlation between PD and AL growth at 0.5 and 1 a follow-ups over 2 a(R2=-0.156, -0.190, both P<0.001).CONCLUSION: After stopping low-concentration atropine in children wearing orthokeratology lenses, AL increased more rapidly than before drug withdrawal, PD decreased, and SE changed little. Compared with continuous medication, discontinuation of medication led to faster progression of AL with little change in diopter, and the larger the PD during orthokeratology lens wear, the slower the progression of AL.

Objective:To explore the risk factors of suicidal ideation among callers with unemployment issues to the Beijing psychological assistance hotline.Methods:Totally 802 callers from the Beijing psychological assis-tance hotline from 2020 to 2023,who identified unemployment as their primary concern.Suicidal ideation was as-sessed by directly asking callers if they had experienced suicidal thoughts within the past two weeks.General demo-graphic information was collected,along with factors related to suicidal ideation,including distress,hope,depres-sion,substance abuse,physical problems,history of previous suicide attempts,chronic life events,acute life events,history of abuse,fear of being attacked,and family or friends' history of suicide.Results:A total of 517 individuals(64.4％)reported experiencing suicidal ideation within the two weeks prior to their call.Regression analysis indi-cated that high levels of hope(OR=0.32,95％CI:0.23-0.44)were a protective factor against suicidal ideation among unemployed callers.In contrast,severe depressive symptoms(OR=2.47,95％CI:1.77-3.45),a history of previous suicide attempts(OR=1.64,95％CI:1.05-2.56),and chronic life events(OR=1.55,95％CI:1.11-2.16)were identified as significant risk factors for suicidal ideation in this group.Conclusion:A history of prior suicide attempts,chronic life events,and high levels of depression are significant risk factors for suicidal idea-tion among unemployed callers,whereas a high level of hope serves as a protective factor.

Objective:To explore the risk factors of suicidal ideation in bereavement callers of Beijing psy-chological support hotline.Methods:Bereavement callers from 2022-2023 hotline callers who were assessed for grief reactions were included in this study.Callers were assessed for current suicidal ideation by asking them if they had suicidal ideation within two weeks.The general demographic data of bereavement callers were collected,and the distress,hope and suicide risk factors of bereavement callers were assessed by hotline interview.The depression de-gree of bereavement callers was assessed by diagnostic screening scale for depression.Logistic regression analysis was used to explore the risk factors of suicidal ideation.Results:Seventy-seven point two percent(1 028/1 332)of callers reported suicidal ideation.Those who were over 25 years old(OR=0.50),with 10-16 years of education(OR=0.59),with over 16 years of education(OR=0.28),and had a high sense of hope(OR=0.41)were less likely to have suicidal ideation.Those with previous suicide history(OR=2.70),high levels of distress(OR=1.72),and high levels of depression(OR=2.86)were more likely to have suicidal ideation.Conclusion:A history of previous suicide,high levels of distress,and high levels of depression among bereavement callers were risk fac-tors for suicidal ideation.

Objective:To explore the risk factors of suicidal ideation among callers with unemployment issues to the Beijing psychological assistance hotline.Methods:Totally 802 callers from the Beijing psychological assis-tance hotline from 2020 to 2023,who identified unemployment as their primary concern.Suicidal ideation was as-sessed by directly asking callers if they had experienced suicidal thoughts within the past two weeks.General demo-graphic information was collected,along with factors related to suicidal ideation,including distress,hope,depres-sion,substance abuse,physical problems,history of previous suicide attempts,chronic life events,acute life events,history of abuse,fear of being attacked,and family or friends' history of suicide.Results:A total of 517 individuals(64.4％)reported experiencing suicidal ideation within the two weeks prior to their call.Regression analysis indi-cated that high levels of hope(OR=0.32,95％CI:0.23-0.44)were a protective factor against suicidal ideation among unemployed callers.In contrast,severe depressive symptoms(OR=2.47,95％CI:1.77-3.45),a history of previous suicide attempts(OR=1.64,95％CI:1.05-2.56),and chronic life events(OR=1.55,95％CI:1.11-2.16)were identified as significant risk factors for suicidal ideation in this group.Conclusion:A history of prior suicide attempts,chronic life events,and high levels of depression are significant risk factors for suicidal idea-tion among unemployed callers,whereas a high level of hope serves as a protective factor.

Objective:To explore the risk factors of suicidal ideation in bereavement callers of Beijing psy-chological support hotline.Methods:Bereavement callers from 2022-2023 hotline callers who were assessed for grief reactions were included in this study.Callers were assessed for current suicidal ideation by asking them if they had suicidal ideation within two weeks.The general demographic data of bereavement callers were collected,and the distress,hope and suicide risk factors of bereavement callers were assessed by hotline interview.The depression de-gree of bereavement callers was assessed by diagnostic screening scale for depression.Logistic regression analysis was used to explore the risk factors of suicidal ideation.Results:Seventy-seven point two percent(1 028/1 332)of callers reported suicidal ideation.Those who were over 25 years old(OR=0.50),with 10-16 years of education(OR=0.59),with over 16 years of education(OR=0.28),and had a high sense of hope(OR=0.41)were less likely to have suicidal ideation.Those with previous suicide history(OR=2.70),high levels of distress(OR=1.72),and high levels of depression(OR=2.86)were more likely to have suicidal ideation.Conclusion:A history of previous suicide,high levels of distress,and high levels of depression among bereavement callers were risk fac-tors for suicidal ideation.

ObjectiveTo investigate the impact of icariin （ICA） on autophagy in glucocorticoid-induced bone microvascular endothelial cells （BMECs） mediated by the phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin （PI3K/Akt/mTOR） signaling pathway. MethodBMECs were isolated and cultured from femoral heads obtained during total hip arthroplasty and identified using immunofluorescence staining. The experimental cells were divided into four groups： A control group， a glucocorticoid group （100 mg·L^-1 hydrocortisone）， an ICA group （100 mg·L^-1 hydrocortisone+6.7×10^-3 mg·L^-1 ICA）， and a Rapamycin group （100 mg·L^-1 hydrocortisone+6.7×10^-3 mg·L^-1 ICA+1 mg·L^-1 rapamycin）. Autophagy in BMECs was induced using 100 mg·L^-1 hydrocortisone. LC3 fluorescence staining was used to observe the peak of autophagy at different time points. Western blot analysis was employed to analyze the expression of autophagy-related proteins and PI3K/Akt/mTOR pathway proteins in each group. Electron microscopy was used to observe autophagosomes and autolysosomes in the cells. ResultHydrocortisone at 100 mg·L^-1 induced autophagy in BMECs， reaching a peak at around 5 hours， which then declined with further intervention. Compared to the control group， the glucocorticoid group showed cell membrane damage， disordered organelle arrangement， and a large number of autophagosomes and autolysosomes. Compared to the glucocorticoid group， the ICA group had more intact cell membranes， sparser organelle arrangement， and fewer autophagosomes and autolysosomes. Compared to the ICA group， the Rapamycin group showed cell membrane damage， disordered organelle arrangement， and more autophagosomes and autolysosomes. Compared to the control group， the glucocorticoid group had significantly increased expression of light chain 3B （LC3B）， Atg4B， and p62 （P<0.01）. Compared to the glucocorticoid group， the ICA group showed significantly decreased expression of LC3B， Atg4B， p62， and Beclin-1 （P<0.01）. Compared to the ICA group， the Rapamycin group had significantly increased expression of Atg4B and p62 （P<0.01）. Compared to the control group， the glucocorticoid group had significantly decreased expression of p-PI3K/PI3K， p-Akt/Akt， and p-mTOR/mTOR （P<0.01）. Compared to the glucocorticoid group， the ICA group showed significantly increased expression of p-PI3K/PI3K， p-Akt/Akt， and p-mTOR/mTOR （P<0.01）. Compared to the ICA group， the Rapamycin group had significantly decreased expression of p-PI3K/PI3K， p-Akt/Akt， and p-mTOR/mTOR （P<0.01）. Ubiquitination levels were significantly decreased in the glucocorticoid group compared to the control group （P<0.01）. Compared to the glucocorticoid group， ubiquitination levels were significantly increased in the ICA group （P<0.01）， and significantly decreased in the Rapamycin group compared to the ICA group （P<0.01）. ConclusionThe glucocorticoid-induced autophagy in BMECs is time-dependent. ICA inhibits glucocorticoid-induced autophagy in BMECs， and this effect may be related to the regulation of the PI3K/Akt/mTOR pathway.

Objective To explore the risk factors for suicidal ideation among the relatives and friends of suicide victims through psychological support hotline.Methods Calls from the relatives and friends of suicide victims to the Beijing psychological support hotline between 2009 and 2023 were included.Their current suicidal ideation was assessed by asking whether they had suicidal thoughts in the past two weeks.Demographic information of the callers was collected and the severity of their depression was assessed using the depression diagnostic screening scale.Interviews were conducted to evaluate distress,sense of hope,history of suicide attempts,and suicide risk factors.Logistic regression analysis was used to explore the risk factors for suicidal ideation among callers.Results A total of 360 cases were included in this study.There were 50.3%(181 cases)of the callers reporting suicidal ideation within 2 weeks before the call.Years of education(OR=0.86,95%CI:0.79-0.94)and high levels of hope(OR=0.19,95%CI:0.11-0.32)were protective factors against suicidal ideation in callers.History of suicide attempts(OR=2.01,95%CI:1.20-3.36),high levels of distress(OR=3.28,95%CI:1.92-5.61),and high levels of depression(OR=1.73,95%CI:1.05-2.84)were independent risk factors for suicidal ideation in callers.Conclusions History of suicide attempts,high levels of distress and high levels of depression among the relatives and friends of suicide victims calling the psychological support hotline are risk factors for their own suicidal ideation.

Objective The distribution of the photon energy spectrum in isocenter plane of the medical linear accelerator and the influence of secondary collimator on the photon energy spectrum are studied.Methods Use the BEAMnrc program to simulate the transmission of the 6 MeV electrons and photons in 5 cm×5 cm,10 cm×10 cm,15 cm×15 cm and 20 cm×20 cm fields in treatment head of the medical linear accelerator,where a phase space file was set up at the isocenter plane to record the particle information passing through this plane.The BEAMdp program is used to analyze the phase space file,in order to obtain the distribution of the photon energy spectrum in isocenter plane and the influence of secondary collimator on the photon energy spectrum.Results By analyzing the photon energy spectrum of a medical linear accelerator with a nominal energy of 6 MV,it is found that the secondary collimator has little effect on the photon energy spectrum;different fields have different photon energy spectrum distributions;the photon energy spectrum in different central regions of the same field have the same normalized distribution.Conclusion In the dose calculation of radiation therapy,the influence of photon energy spectrum should be carefully considered.