Objective: To understand the prevalence of myopia among primary and secondary school students in minority areas of Yunnan Province, and to explore the influence of outdoor activities and short-distance use of eyes, so as to provide a basis for early myopia intervention. Methods: In October 2020, the survey was conducted among 1 782 primary and secondary school students in three cities of Yunnan through a multi stage random cluster sampling method. All subjects underwent a questionnaire survey and the visual acuity examination at baseline. The first follow-up was conducted in October 2021 to obtain 1 691 valid samples, and the second follow-up was conducted in May 2023 to obtain 1 367 valid samples. Factors associated with myopia among primary and secondary school students were explored by using generalized estimating equations. Results: The prevalence rates of myopia in 2020, 2021 and 2023 were 52.64%, 61.62% and 69.35%, respectively, showing an increasing trend ( χ 2 trend =91.77, P <0.05). The results of multivariate regression analysis on the generalized estimation equations showed that age at baseline ( OR =1.31), girls ( OR =1.76), Hani ethnicity ( OR =0.75), Bai ethnicity ( OR =0.69), parental myopia ( OR =1.97-2.29), parents often reducing children s exercise time for homework or tutoring ( OR =1.35), less than 1 time or 2-3 times of ball sports per week ( OR =1.27, 1.20 ), reading and writing in the classroom during the break ( OR =1.27), reading in direct sunlight occasionally ( OR =1.20), using only desk lamp for writing at home ( OR =0.71), more than 1 hours of short-distance eye use for a break once ( OR =1.23) were associated with myopia among primary and secondary school students ( P <0.05). Conclusions Outdoor activities and short-distance use of eye among primary and middle school students in minority areas in Yunnan province are suboptimal. Enhancing the related environmental and behavioral factors can effectively mitigate the occurrence and progression of myopia.

M2 protein of influenza A virus is encoded by a spliced mRNA derived from RNA segment 7 and plays an important role in influenza virus replication. It is also a target molecule of anti-virus drugs. We extracted the viral genome RNAs from MDCK cells infected with swine influenza A virus (SIV) H3N2 subtype and amplified the SIV M2 gene by reverse transcriptase-polymerase chain reaction using the isloated viral genome RNAs as template. The amplified cDNA was cloned into a prokaryotic expression vector pET-28a(+) (designated pET-28a(+)-M2) and a eukaryotic expression vector p3xFLAG-CMV-7.1 (designated p3xFLAG-CMV-7.1-M2), respectively. The resulted constructs were confirmed by restriction enzyme digestion and DNA sequencing analysis. We then transformed the plasmid pET-28a(+)-M2 into Escherichia coli BL21 (DE3) strain and expressed it by adding 1 mmol/L of IPTG (isopropyl-beta-D-thiogalactopyranoside). The recombinant M2 protein was purified from the induced bacterial cells using Ni(2+) affinity chromatography. Wistar rats were immunized with the purified M2 protein for producing polyclonal antibodies specific for it. Western blotting analysis and immunofluorescence analysis showed that the produced antibodies were capable of reacting with M2 protein expressed in p3xFLAG-CMV-7.1-M2-transfected cells as well as that synthesized in SIV-infected cells. We also transfected plasmid p3xFLAG-CMV-7.1-M2 into Vero cells and analyzed its subcellular localization by immunofluorescence. The M2 protein expressed in the Vero cells was 20 kDa in size and dominantly localized in the cytoplasm, showing a similar distribution to that in SIV-infected cells. Western blotting analysis of SIV-infected cells suggested that M2 was a late phase protein, which was detectable 12 h post-infection, later than NS1, NP and M1 proteins. It would be a potential molecular indicator of late phases replication of virus. Our results would be useful for studying the biological function of M2 protein in SIV replication.
Animals ; Antibodies, Monoclonal ; biosynthesis ; Cercopithecus aethiops ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Influenza A Virus, H3N2 Subtype ; genetics ; RNA ; biosynthesis ; genetics ; Rats ; Rats, Wistar ; Recombinant Proteins ; biosynthesis ; genetics ; immunology ; Swine ; Transfection ; Vero Cells ; Viral Matrix Proteins ; biosynthesis ; genetics ; Virus Replication ; genetics

Ebola virus (EBOV) causes highly lethal hemorrhagic fever in humans and nonhuman primates and has a significant impact on public health. The nucleoprotein (NP) of EBOV (EBOV-NP) plays a central role in virus replication and has been used as a target molecule for disease diagnosis. In this study, we generated a monoclonal antibody (MAb) against EBOV-NP and mapped the epitope motif required for recognition by the MAb. The MAb generated via immunization of mice with prokaryotically expressed recombinant NP of the Zaire Ebola virus (ZEBOV-NP) was specific to ZEBOV-NP and able to recognize ZEBOV-NP expressed in prokaryotic and eukaryotic cells. The MAb cross-reacted with the NP of the Reston Ebola virus (REBOV), the Cote-d'Ivoire Ebola virus (CIEBOV) and the Bundibugyo Ebola virus (BEBOV) but not with the NP of the Sudan Ebola virus (SEBOV) or the Marburg virus (MARV). The minimal epitope sequence required for recognition by the MAb was the motif PPLESD, which is located between amino acid residues 583 and 588 at the C-terminus of ZEBOV-NP and well conserved among all 16 strains of ZEBOV, CIEBOV and BEBOV deposited in GenBank. The epitope motif is conserved in four out of five strains of REBOV.
Animals ; Antibodies, Monoclonal ; immunology ; Ebolavirus ; chemistry ; immunology ; Epitope Mapping ; methods ; Escherichia coli ; genetics ; metabolism ; Mice ; Mice, Inbred BALB C ; Nucleoproteins ; immunology ; Recombinant Proteins ; biosynthesis ; genetics ; immunology

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.

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.

Objective To assess ocular biometric parameters among primary and secondary school students from Naxi,Bai and Han ethnic groups in Yunnan Province.Methods The school-based study was conducted in October 2020.A total of 724 second-,third-and seventh-graders were selected from Dali and Lijiang,where Bai and Naxi ethnic groups inhabit,using a stratified cluster sampling method to receive questionnaire surveys and eye examinations.Non-cycloplegic spherical equivalent(SE),axial length(AL),anterior chamber depth(ACD),corneal radius of curvature(CR),central corneal thickness(CCT),white-to-white(WTW)distance,and the AL/CR ratio were measured.Covariance analysis was used to examine the differences in SE and ocular biometric parameters in terms of ethnicity,sex and grade,while Pearson correlation was used to test the associations among the said indicators.Results There were no significant differences in daily outdoor time,screen time and sleep time among the three ethnic groups regardless of grades(all P＞0.05).The mean CCT of Naxi students was lower than that of Han and Bai students[grade 2 and grade 3:(542.48±39.76)μm vs.(553.81±31.83)μm and(559.27±32.79)μm;grade7:(538.86±34.91)μm vs.(547.41±33.55)μm and(548.26± 32.98)μm,all P＜0.05],while no significant differences were found in the other ocular biometric parameters among the three ethnic groups(all P＞0.05).Among the seventh-graders,the SE,AL and AL/CR ratio of Naxi students were signifi-cantly different from those of Han and Bai students(all P＜0.05).The AL,CR,ACD,CCT,WTW distance,and mean SE were lower in girls than in boys(all P＜0.05).Compared with grade 2 and grade 3,students of grade 7 had longer AL,deeper ACD and thinner CCT(all P＜0.05),while no significant differences were found in CR and WTW distance(all P＞0.05).Correlation analysis showed that the AL/CR ratio was highly correlated with SE(r=-0.78,P＜0.05).Conclu-sion Multiethnic primary and secondary school students may face similar environmental risks.Yet,disparities in ocular biometric parameters caused by ethnicity,sex and age should be noted.