Objective:To obtain a prevalent respiratory syncytial virus (RSV) clinical isolate in Beijing and analyze the genotype and biological characteristics of the strain.Methods:A nasopharyngeal secretion specimen was collected from a child with RSV infection in Beijing in 2023 and used for viral isolation. Viral nucleic acid was amplified using qRT-PCR. The isolated virus was identified by transmission electron microscopy, indirect immunofluorescence assay, and plaque formation assay. A phylogenetic analysis was conducted based on the whole-genome sequencing results. Virus titers were determined, and replication characteristics were analyzed. The efficacy of the isolated strain for in vitro screening of antiviral drugs was validated. Results:A clinical RSV isolate, named hRSV/C-Tan/BJ 202301, was successfully isolated, which could form syncytia in Hep-2 cells. Spherical, filamentous, and irregular virus particles were observed by electron microscopy. Immunofluorescence detection showed green fluorescence in Hep-2 cells, and plaque assay showed round plaques, which were similar to the Long strain in morphology. Genomic sequence analysis showed that it belonged to ON1 genotype. It exhibited similar cell growth kinetics characteristics with the Long strain and could be used for antiviral drug screening in vitro. Conclusions:In this study, one RSV strain is successfully isolated and identified. The biological characteristics and the phylogenetic relationship of this strain reflect the characteristics of the circulating strains in Beijing, which provides experimental material for RSV vaccine development and antiviral drug screening in China.

Objective: To explore the relationship of physical activity (PA) and sedentary behavior (SB) with cardiorespiratory fitness (CRF) among middle schoold students in Tibet, so as to provide empirical references for improving the cardiorespiratory fitness and health levels of adolescents in Tibet. Methods: From August to December 2020, 1 225 junior and senior high school students were selected from 2 middle schools in Lhasa, Tibet Autonomous Region, using the stratified cluster random sampling method. Triaxial accelerometers were used to evaluate PA and SB behaviors, and the 20 meter shuttle run was employed to assess CRF among the middle school students. Isochronous substitution modeling was used to analyze the associations of SB, low intensity physical activity (LPA), and moderate vigorous physical activity (MVPA) with CRF, and the saturation threshold effect in the dose response relationship between MVPA and CRF was analyzed through restricted cubic spline and two stage linear regression. Results: After adjusting for covariates such as gender, body mass index and sleep quality score, isotemporal substitution analysis showed that among junior high school students aged 13-15, replacing 30 minutes of SB ( B =1.73) or LPA ( B =2.38) with MVPA were positively associated with CRF (both P <0.05). Among senior high school students aged 16-18, replacing SB ( B =0.99) or LPA ( B =1.38) with MVPA were also positively associated with CRF (both P <0.05). Restricted cubic spline and two piecewise linear regression analyses indicated that only middle school girls aged 13-18 exhibited a saturation threshold effect between MVPA and CRF (logarithmic likelihood ratio test=0.03), with the optimal CRF improvement observed at 60 minutes of MVPA per day ( B=0.13, P ＜ 0.01). Conclusions Reducing SB and LPA while increasing MVPA can improve CRF in Tibetan middle school students. To maximize CRF improvement, middle school girls should engage in at least 60 minutes of MVPA daily.

Objective To explore the clinical effect of quality control circle(QCC)activities on the prevention of postoperative deep vein thrombosis(DVT)in inpatients in military hospitals.Methods A total of 318 patients who were diagnosed and treated in The First Affiliated Hospital of Air Force Medical University from January to December 2021 and 40 medical staff were enrolled in this study.Routine care was performed in 158 patients from January to June 2021,and QCC care was implemented in 160 patients from July to December 2021.The awareness of DVT prevention in medical staff and patients(or their famiy members)before and after QCC activities,lower limb DVT preventive measures taken by medical staff,and the occurrence of DVT were compared.Results The scores of the cause,clinical manifestations,nursing measures and preventive measures of DVT after QCC activities were significantly higher than those before QCC activities in both medical staff and patients(or their families)(P<0.05).The overall implementation rate of preventing lower limb DVT after QCC activities was significantly higher than that before QCC activities(94.14%vs.46.20%,P<0.05).The incidence of DVT after QCC activities was significantly lower than that before QCC activities(0.62%vs.5.06%,P<0.05).Conclusion Implementing QCC activities can improve the cognitive ability of military medical staff and patients(or family members)in DVT prevention,increase the implementation rate of DVT prevention measures,and reduce the incidence of DVT.

Convergence insufficiency intermittent exotropia (CI-IXT) is a subtype of intermittent exotropia.Surgery remains the most commonly used treatment.Improved unilateral lateral rectus recession-medial rectus resection (I-RR), slanted or nonslanted bilateral medial rectus resection (BMRs) and bilateral slanted lateral rectus recession (S-BLRc) are the commonly used modalities for surgical treatment.These treatment modalities have been able to correct distance and near exotropia and simultaneously reduce the near-distance difference.The clinical application of slanted or nonslanted BMRs is limited due to exodrift over time.I-RR and S-BLRc are widely used in clinics for patients with CI-IXT because of better long-term outcomes.A good knowledge of the different indications of each procedure and its appropriate application can lead to good clinical results.This article reviews recent advances in the surgical management of CI-IXT.

Objective:To investigate the myopia progression in Chinese young medical college students and explore the associated risk factors.Methods:A cohort study was conducted.Among 1 068 freshmen aged 16 to 22 years receiving health checkups at a medical university in Tianjin, 979 myopes were ultimately included in the baseline assessment and 812 participated in the follow-up assessment after two years.The anterior segment examination with a slit lamp, non-cycloplegic autorefraction with an autorefractor and axial length (AL) measurements with Lenstar 900 were performed on participants at baseline and during the two-year follow-up.Myopia progression was defined as a spherical equivalent (SE) change of ≤-0.50 D/year or an AL increase of ≥0.20 mm/year.Multivariate regression analysis with the generalized estimating equation model was employed to identify risk factors associated with myopia progression.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Tianjin Medical University Eye Hospital (No.2021KY-16).Informed consent was obtained from each subject.Results:During the two-year follow-up, 92.5%(751/812) of the participants had stable SE and 96.1%(764/795) had stable AL.However, 7.5%(61/812) showed SE progression and 3.9%(31/795) exhibited AL growth, demonstrating a tendency of myopia progression.Multivariate linear regression analysis revealed that females ( β=0.064, 95% CI: 0.002~0.126; P=0.042) and low to moderate myopia at baseline ( β=0.083, 95% CI: 0.005~0.161; P=0.037) were significantly associated with AL growth compared to high myopia at baseline. Conclusions:More than 92% of young college students have stable myopia.In addition to high myopia, there is still a need for better follow-up and management of females and those with low to moderate myopia to control the high prevalence of high myopia.

Objective:To compare the changes in spherical equivalent (SE) and axial length (AL) between children with axial myopia and refractive myopia.Methods:A prospective cohort study was conducted.A total of 1 738 students from grades 1 to 6 were recruited from two consistent 9-year schools in the Binhai New Area of Tianjin using cluster random sampling.Visual acuity, refractive status, and ocular biological parameters were measured from February to May in 2018 and 2021.Participants were categorized into subgroups as follows: low, moderate, and high myopia based on SE; longer AL group and shorter AL groups based on AL; and steeper cornea and flatter cornea groups based on corneal curvature radius (CCR). Myopic children were further classified into the following groups: axial myopia (longer AL and flatter cornea), refractive myopia (shorter AL and steeper cornea), mixed myopia (longer AL and steeper cornea), and non-axial non-refractive myopia (shorter AL and flatter cornea). Changes in SE (ΔSE) and AL (ΔAL) at the end of the follow-up period were compared among the different classification groups.This study adhered to the Declaration of Helsinki and was approved by the Ethics Committee of Tianjin Medical University Eye Hospital (No.2020KY-39). Written informed consent was obtained from the guardians of all participants.Results:The ΔSE in the longer AL group was (-1.57±1.52)D, which was significantly greater than (-1.17±1.47)D in the shorter AL group ( t=3.99, P<0.01). The ΔAL in the steeper cornea group was (0.92±0.50)mm, which was significantly greater than (0.86±0.54)mm in the flatter cornea group ( t=-2.12, P=0.04). Among children aged 10-12 years, males, and the low myopia, SE progression was faster in those with longer AL compared to shorter AL, with statistically significant differences ( t=2.66, 3.31, 3.90; all P<0.05). In children aged 10-12 years, AL growth was faster in the longer AL group than in the shorter AL group, with a statistically significant difference ( t=-1.29, P=0.04). Among females and the low myopia, AL growth was faster in those with steeper corneas than in those with flatter corneas, with statistically significant differences ( t=-3.22, -2.43; both P<0.05). Refractive myopia had a smaller ΔSE than axial myopia and the difference was statistically significant ( P<0.05). Within the low myopia, SE progression was greater in axial myopia than in refractive myopia, with a statistically significant difference ( P<0.05). Conclusions:Among myopic children, those with longer axial lengths exhibit faster SE progression, while those with steeper corneas show faster axial elongation.Among children with low myopia, axial myopia is associated with a greater risk of SE progression than refractive myopia.

Objective To compare the efficacy of controlling pediatric myopia progression between defocus incorpo-rated multiple segments(DIMS)spectacle lenses combined with low-concentration atropine(0.1 g·L-1)(DIMSA)and orthokeratology(OK)lenses.Methods A prospective cohort study was conducted on myopic children treated at the De-partment of Ophthalmology,Children's Hospital of Nanjing Medical University between January 2022 and February 2023.Participants were divided into a DIMSA group(88 cases)and an OK lens group(73 cases).Only right eye data were in-cluded for statistical analysis,and the children were followed up for 1 year.The axial length(AL)and spherical equivalent refraction(SER)were measured for the DIMSA group while only AL was measured for the OK lens group at baseline and each follow-up visit.The AL regression rate[(AL regression rate=the number of AL regression cases/total cases in the group)× 100％]and axial elongation(AE)were calculated to compare the myopia control efficacy between the two groups.Results The baseline age of the OK lens group was significantly larger than that of the DIMSA group(P=0.001).The AE value in the DIMSA group was significantly smaller than that in the OK lens group after following up for 6 months,following up for 1 year,and adjusting for baseline age(all P＜0.05).Multiple linear regression analysis revealed that baseline age was the only factor influencing the AE value[OK lens group:unstandardized β=-0.024,standardizedβ=-0.266(P=0.022);DIMSA group:unstandardized β=-0.052,standardized β=-0.487(P＜0.001)].There was a negative correlation between AE and baseline age(OK lens group:r=-0.30,P＜0.001;DIMSA group:r=-0.42,P＜0.001).In the DIMSA group,baseline age was positively correlated with SER progression(r=0.28,P=0.001 5).After following up for 1 year,the proportions of children with different AE velocities differed significantly between the two groups(x2=11.09,P=0.004).AE was controlled better in the DIMSA group than that in the OK lens group.AL regression rates in the DIMSA group were significantly higher than those in the OK lens group after 6 months and 1 year of follow-up(all P＜0.05).No severe ocular adverse events occurred in either group.Conclusion DIMSA demonstrates superior effi-cacy over OK lenses in controlling myopia progression in children with mild-to-moderate myopia.Ophthalmologists should tailor myopia control strategies based on individual needs and characteristics.

Convergence insufficiency intermittent exotropia (CI-IXT) is a subtype of intermittent exotropia.Surgery remains the most commonly used treatment.Improved unilateral lateral rectus recession-medial rectus resection (I-RR), slanted or nonslanted bilateral medial rectus resection (BMRs) and bilateral slanted lateral rectus recession (S-BLRc) are the commonly used modalities for surgical treatment.These treatment modalities have been able to correct distance and near exotropia and simultaneously reduce the near-distance difference.The clinical application of slanted or nonslanted BMRs is limited due to exodrift over time.I-RR and S-BLRc are widely used in clinics for patients with CI-IXT because of better long-term outcomes.A good knowledge of the different indications of each procedure and its appropriate application can lead to good clinical results.This article reviews recent advances in the surgical management of CI-IXT.

Objective:To investigate the myopia progression in Chinese young medical college students and explore the associated risk factors.Methods:A cohort study was conducted.Among 1 068 freshmen aged 16 to 22 years receiving health checkups at a medical university in Tianjin, 979 myopes were ultimately included in the baseline assessment and 812 participated in the follow-up assessment after two years.The anterior segment examination with a slit lamp, non-cycloplegic autorefraction with an autorefractor and axial length (AL) measurements with Lenstar 900 were performed on participants at baseline and during the two-year follow-up.Myopia progression was defined as a spherical equivalent (SE) change of ≤-0.50 D/year or an AL increase of ≥0.20 mm/year.Multivariate regression analysis with the generalized estimating equation model was employed to identify risk factors associated with myopia progression.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Tianjin Medical University Eye Hospital (No.2021KY-16).Informed consent was obtained from each subject.Results:During the two-year follow-up, 92.5%(751/812) of the participants had stable SE and 96.1%(764/795) had stable AL.However, 7.5%(61/812) showed SE progression and 3.9%(31/795) exhibited AL growth, demonstrating a tendency of myopia progression.Multivariate linear regression analysis revealed that females ( β=0.064, 95% CI: 0.002~0.126; P=0.042) and low to moderate myopia at baseline ( β=0.083, 95% CI: 0.005~0.161; P=0.037) were significantly associated with AL growth compared to high myopia at baseline. Conclusions:More than 92% of young college students have stable myopia.In addition to high myopia, there is still a need for better follow-up and management of females and those with low to moderate myopia to control the high prevalence of high myopia.

Objective:To compare the changes in spherical equivalent (SE) and axial length (AL) between children with axial myopia and refractive myopia.Methods:A prospective cohort study was conducted.A total of 1 738 students from grades 1 to 6 were recruited from two consistent 9-year schools in the Binhai New Area of Tianjin using cluster random sampling.Visual acuity, refractive status, and ocular biological parameters were measured from February to May in 2018 and 2021.Participants were categorized into subgroups as follows: low, moderate, and high myopia based on SE; longer AL group and shorter AL groups based on AL; and steeper cornea and flatter cornea groups based on corneal curvature radius (CCR). Myopic children were further classified into the following groups: axial myopia (longer AL and flatter cornea), refractive myopia (shorter AL and steeper cornea), mixed myopia (longer AL and steeper cornea), and non-axial non-refractive myopia (shorter AL and flatter cornea). Changes in SE (ΔSE) and AL (ΔAL) at the end of the follow-up period were compared among the different classification groups.This study adhered to the Declaration of Helsinki and was approved by the Ethics Committee of Tianjin Medical University Eye Hospital (No.2020KY-39). Written informed consent was obtained from the guardians of all participants.Results:The ΔSE in the longer AL group was (-1.57±1.52)D, which was significantly greater than (-1.17±1.47)D in the shorter AL group ( t=3.99, P<0.01). The ΔAL in the steeper cornea group was (0.92±0.50)mm, which was significantly greater than (0.86±0.54)mm in the flatter cornea group ( t=-2.12, P=0.04). Among children aged 10-12 years, males, and the low myopia, SE progression was faster in those with longer AL compared to shorter AL, with statistically significant differences ( t=2.66, 3.31, 3.90; all P<0.05). In children aged 10-12 years, AL growth was faster in the longer AL group than in the shorter AL group, with a statistically significant difference ( t=-1.29, P=0.04). Among females and the low myopia, AL growth was faster in those with steeper corneas than in those with flatter corneas, with statistically significant differences ( t=-3.22, -2.43; both P<0.05). Refractive myopia had a smaller ΔSE than axial myopia and the difference was statistically significant ( P<0.05). Within the low myopia, SE progression was greater in axial myopia than in refractive myopia, with a statistically significant difference ( P<0.05). Conclusions:Among myopic children, those with longer axial lengths exhibit faster SE progression, while those with steeper corneas show faster axial elongation.Among children with low myopia, axial myopia is associated with a greater risk of SE progression than refractive myopia.