Objective This study aimed to estimate the therapeutic effects of preformed metal crown(PMC)and pre-fabricated zirconia crowns(ZC)on decayed primary morals in children,as well as to analyze the possible influencing fac-tors.Methods A retrospective cohort study was performed on the data of 192 patients(aged 3 to 8)in the Stomatologi-cal Department of Shenzhen Children's Hospital from October 2021 to December 2021.The decayed mandibular first molars were selected and restored by vital-pulp therapy followed by PMC and ZC,including 96 cases(96 caries)in the PMC group and 96 cases(96 caries)in the ZC group.Oral clinical examination was performed at 3 months,1 year,and 2 years after treatment,overwiewing the clinical therapeu-tic effects and periodontal status of PMC and ZC groups,as well as recording the crown integrity,gingival index(GI),probing bleeding index(BI),plaque index(PLI)and various prosthetic indices.Results No significance differences existed in the periodontal status of PMC and ZC groups at 3 months,1 year,and 2 years after treatment(P>0.05).However,the GI,BI,and PLI in the PMC group were higher than those in the ZC group at 3 months,1 year,and 2 years after treatment,and the difference was dramatically signifi-cant(P<0.05).No significances difference existed in various prosthetic indices(P>0.05),as well as in the GI,BI,and PLI,between the two groups(P>0.05).No significant differences existed in various prosthetic indices between genders after PMC restoration(P>0.05).The scores of girls in various prosthetic indices after ZC restoration were higher than those of boys(P<0.05).Pearson correlation analysis indicated an inverse correlation between age in the PMC group and the GI,BI,PLI,and FDI indices(P<0.01),rather than in the ZC group(P>0.05).Conclusion PMC and ZC can be ap-plied to restore deciduous molar caries.The periodontal status of deciduous teeth in ZC group was superior to that in the PMC group.The periodontal status of deciduous teeth in PMC group may be stable with increased age.

Objective: To describe the linear growth trajectory and BMI growth trajectory of children aged 0-6 years, and to investigate the relationship between different growth trajectory patterns and refractive error of preschool children. Methods: The participants were selected from Ma anshan Birth Cohort Study (MABC), which was established from May 2013 to September 2014. In this study, 15 follow up interviews were conducted among 2 037 live births between 42 days after birth and 72 months of age to collect the data of body length and body weight. And at the age of (72±6) months, data of the naked eye visual acuity was measured by professional ophthalmologist in Ma anshan Maternal and Child Health Hospital. The latent class growth model was conducted to identify distinct linear growth trajectory and BMI Z score trajectories of 0 to 6 year old infants and young children. Multinomial Logistic regression model was used for analyzing the relationship between distinct growth trajectories and ametropia in 6-year-old children. Results: According to the latent class growth model, children showed three obvious linear growth trajectories: slow growth trajectory ( n =302), normal growth trajectory ( n =1 162), and fast growth trajectory ( n =573). And BMI growth trajectory were also divided into three patterns: slow growth trajectory ( n =630), normal growth trajectory ( n =1 058), and fast growth trajectory ( n =349). Multinomial Logistic regression analysis showed that linear slow growth trajectory was a risk factor for hyperopia in 6-year-old children ( OR =1.80, 95% CI =1.09-2.98, P <0.05). But it was not significantly associated with myopia. There was no significant correlation between fast growth BMI pattern and slow growth BMI pattern with myopia and hyperopia in 6-year-old children. Conclusion Slower growth patterns in linear growth trajectories were associated with hyperopia in 6-year-old children.It should pay close attention to the height growth pattern of preschool children. Regular examination of physical development indicators and distance vision can help prevent the occurrence and development of ametropia in preschool children.

Multiple plant lineages have independently evolved sex chromosomes and variable kary-otypes to maintain their sessile lifestyles through constant biological innovation.Morus notabilis,a dioecious mulberry species,has the fewest chromosomes among Morus spp.,but the genetic basis of sex determination and karyotype evolution in this species has not been identified.In this study,three high-quality genome assemblies were generated for Morus spp.[including dioecious M.notabilis(male and female)and Morus yunnanensis(female)]with genome sizes of 301-329 Mb and were grouped into six pseudochromosomes.Using a combination of genomic approaches,we found that the putative ancestral karyotype of Morus species was close to 14 protochromosomes,and that sev-eral chromosome fusion events resulted in descending dysploidy(2n=2x=12).We also charac-terized a～6.2-Mb sex-determining region on chromosome 3.Four potential male-specific genes,a partially duplicated DNA helicase gene(named MSDH)and three Ty3_Gypsy long terminal repeat retrotransposons(named MSTG1/2/3),were identified in the Y-linked area and considered to be strong candidate genes for sex determination or differentiation.Population genomic analysis showed that Guangdong accessions in China were genetically similar to Japanese accessions of mul-berry.In addition,genomic areas containing selective sweeps that distinguish domesticated mul-berry from wild populations in terms of flowering and disease resistance were identified.Our study provides an important genetic resource for sex identification research and molecular breeding in mulberry.

Objective To investigate the value of magnetic resonance imaging-proton density fat fraction (MRI-PDFF) and FibroScan in the quantitative evaluation of liver fat content in patients with chronic hepatitis B (CHB). Methods A total of 96 patients with CHB who were hospitalized in Department of Hepatology, The Second Clinical Medical College of Guangzhou University of Chinese Medicine, from February 2017 to July 2020 were enrolled, and all patients were diagnosed based on liver pathological examination. MRI-PDFF and FibroScan were performed before surgery. According to the results of liver biopsy, the patients were divided into non-fatty liver disease group with 44 patients, mild fatty liver disease group with 33 patients, and moderate-to-severe fatty liver disease group with 19 patients. A one-way analysis of variance was used for comparison of normally distributed continuous data between multiple groups, and the least significant difference t -test was used for further comparison between two groups; the Kruskal-Wallis H test was used for comparison of non-normally distributed continuous data between multiple groups, and the Mann-Whitney U test was used for further comparison between two groups; Bonferroni correction was also performed. The receiver operating characteristic (ROC) curve was plotted to analyze the area under the ROC curve (AUC) of hepatic fat fraction (HFF) and controllable attenuation parameters (CAP) in the diagnosis of fatty liver disease and obtain their sensitivities, specificities, and optimal cut-off values. The intraclass correlation coefficient was used to investigate the consistency of MRI-PDFF data. Results The moderate-to-severe fatty liver disease group had a significant increase in MRI-PDFF HFF compared with the non-fatty liver disease group and the mild fatty liver disease group (all P < 0.05), and the mild fatty liver disease group had a significant increase in MRI-PDFF HFF compared with the non-fatty liver disease group( P < 0.05). The moderate-to-severe fatty liver disease group had a significant increase in FibroScan CAP compared with the non-fatty liver disease group and the mild fatty liver disease group (all P < 0.05), and the mild fatty liver disease group had a significant increase in FibroScan CAP compared with the non-fatty liver disease group ( P < 0.05). In the diagnosis of mild fatty liver disease, MRI-PDFF HFF had an AUC of 0.901 ( P < 0.001), a sensitivity of 90.9%, and a specificity of 82.7% at the optimal cut-off value of 5.1%, and in the diagnosis of moderate-to-severe fatty liver disease, MRI-PDFF HFF had an AUC of 0.972 ( P < 0.001), a sensitivity of 96.1%, and a specificity of 89.5% at the optimal cut-off value of 9.7%. In the diagnosis of mild fatty liver disease, FibroScan CAP had an AUC of 0.829 ( P < 0.001), a sensitivity of 77.3%, and a specificity of 78.8% at the optimal cut-off value of 258.5 dB/m, and in the diagnosis of moderate-to-severe fatty liver disease, FibroScan CAP had an AUC of 0.830 ( P < 0.001), a sensitivity of 76.6%, and a specificity of 78.9% at the optimal cut-off value of 285.5 dB/m. Conclusion Both MRI-PDFF and FibroScan can objectively evaluate the degree of fatty liver disease in patients with CHB. MRI-PDFF HFF and FibroScan CAP can be used as noninvasive markers for the quantitative analysis of CHB with hepatic steatosis, and MRI-PDFF HFF tends to have higher diagnostic efficiency.

Objective:To investigate the clinical effect of minimally invasive scar release combined with autologous microfat graft in the treatment of facial depressed scar.Methods:From September 2015 to May 2019, a total of 11 patients who had facial depressed scar were treated with minimally invasive scar release combined with autologous microfat graft in Huaihe Hospital of Henan University. Needle scar separator or 10 ml syringe needle was inserted under skin to release scar adhesion thoroughly. Microfat was harvested from the abdomen, which was separated and purified, and then evenly transplanted into the stripped space (0.5 cm wider than the edge of scar) under the scar with a 1 ml syringe. The severity of scar was evaluated pre-operation, 3-month post-operation and 6-month post-operation, using Vancouver Scar Scale score and Stony Brook Scar Evaluation Scale score to evaluate the efficacy. Using Visual Analogue Scale score to evaluate patient satisfaction. Analyses were performed using SPSS Statistics 25.0, and measurement data were expressed as Mean±SD if they conformed to normality and homogeneity of variance. One-way ANOVA was used for multi-time point data, and the Bonferroni test was performed for pairwise comparison. P<0.05 was considered a statistically significant difference. Results:The depression of scars disappeared immediately after treatment. 6 months after treatment, the surface of the scars was flat, the color and elasticity were close to adjacent normal skin, and the texture of the scars was soft. All patients were followed up for 6 months without recurrence, and 11 patients were satisfied. In Vancouver Scar Scale score, the pre-operation score was 7.27±1.10, the 3-month post-operation score was 2.64±0.81 and the 6-month post-operation score was 0.91±0.54, showing a significant difference ( F=467.98, P<0.001). Pairwise comparison result show that comparing the pre-operation score with 3 or 6 months post-operation score, showing a significant difference ( P<0.001). The comparison between 3 and 6 months post-operation score also showing a significant difference ( P<0.001). In Stony Brook Scar Evaluation Scale score, the pre-operation score was (2.00±0.89), the 3-month post-operation score was 4.45±0.69 and the 6-month post-operation score was 4.45±0.69, showing a significant difference ( F=67.00, P<0.001). Pairwise comparison result show that comparing pre-operation score with 3 or 6 months post-operation score, showing a significant difference ( P<0.001). The comparison between 3 and 6 months post-operation score also showing a significant difference ( P=0.006). The 6-month post-operation Visual Analogue Scale score was 95.0±6.74. Conclusions:Minimally invasive scar release combined with autologous microfat graft in the treatment of facial depressed scar can avoid the post-surgery scar formation and adhesion, and improve the color and texture of the facial hypertrophic scar. This method can be carried out under local anesthesia, with simple procedure and exact effect.

Objective:To analyze the relationship between migration time and the prevalence of myopia of children and adolescents aged between 6 and 18 years old in Shenzhen.Methods:From April to May 2019, 26 618 children and adolescents from 14 schools in six streets of Baoan District, including Fuyong, Shajing, Xin′an, Xixiang, Songgang and Shiyan, were included in the study by using random cluster sampling method. The demographic characteristics, migration status, self-reported myopia, screen time in the last seven days, outdoor activities in the last one month and other information were collected through the questionnaire. The differences of myopia among children and adolescents with different characteristics were compared by χ 2 test, and the relationship between migration time and the prevalence of myopia was analyzed by multivariate unconditional logistic regression model. Results:The age of 26 618 study participants was (12.37±3.49) years old, and the overall prevalence of myopia was 49.4%. Multivariate logistic regression analysis showed that after controlling for relevant confounding factors, compared with migrant children and adolescents of migrant workers who migrated for 1-2 years, those of migrant workers who had migrated for more than 6 years had a higher risk of myopia [ OR (95% CI): 1.48 (1.14-1.92)]. After being grouped by phase of school, in the lower grade group of primary school, the children and adolescents of migrant workers who had migrated for more than 6 years had a higher risk of myopia compared with those of migrant workers who migrated for 1-2 years [ OR (95% CI): 1.96 (1.20-2.74)]. In the high school group, compared with the children and adolescents of migrant workers who migrated for 1-2 years, those of migrant workers who had migrated for 3-5 years and ≥6 years had a higher risk of myopia [ OR (95% CI): 6.03 (1.29-28.15) and 6.52 (1.51-28.11), respectively]. Conclusion:The migration time is related to the prevalence of myopia of the children and adolescents of migrant workers.

Objective:To investigate the clinical effect of minimally invasive scar release combined with autologous microfat graft in the treatment of facial depressed scar.Methods:From September 2015 to May 2019, a total of 11 patients who had facial depressed scar were treated with minimally invasive scar release combined with autologous microfat graft in Huaihe Hospital of Henan University. Needle scar separator or 10 ml syringe needle was inserted under skin to release scar adhesion thoroughly. Microfat was harvested from the abdomen, which was separated and purified, and then evenly transplanted into the stripped space (0.5 cm wider than the edge of scar) under the scar with a 1 ml syringe. The severity of scar was evaluated pre-operation, 3-month post-operation and 6-month post-operation, using Vancouver Scar Scale score and Stony Brook Scar Evaluation Scale score to evaluate the efficacy. Using Visual Analogue Scale score to evaluate patient satisfaction. Analyses were performed using SPSS Statistics 25.0, and measurement data were expressed as Mean±SD if they conformed to normality and homogeneity of variance. One-way ANOVA was used for multi-time point data, and the Bonferroni test was performed for pairwise comparison. P<0.05 was considered a statistically significant difference. Results:The depression of scars disappeared immediately after treatment. 6 months after treatment, the surface of the scars was flat, the color and elasticity were close to adjacent normal skin, and the texture of the scars was soft. All patients were followed up for 6 months without recurrence, and 11 patients were satisfied. In Vancouver Scar Scale score, the pre-operation score was 7.27±1.10, the 3-month post-operation score was 2.64±0.81 and the 6-month post-operation score was 0.91±0.54, showing a significant difference ( F=467.98, P<0.001). Pairwise comparison result show that comparing the pre-operation score with 3 or 6 months post-operation score, showing a significant difference ( P<0.001). The comparison between 3 and 6 months post-operation score also showing a significant difference ( P<0.001). In Stony Brook Scar Evaluation Scale score, the pre-operation score was (2.00±0.89), the 3-month post-operation score was 4.45±0.69 and the 6-month post-operation score was 4.45±0.69, showing a significant difference ( F=67.00, P<0.001). Pairwise comparison result show that comparing pre-operation score with 3 or 6 months post-operation score, showing a significant difference ( P<0.001). The comparison between 3 and 6 months post-operation score also showing a significant difference ( P=0.006). The 6-month post-operation Visual Analogue Scale score was 95.0±6.74. Conclusions:Minimally invasive scar release combined with autologous microfat graft in the treatment of facial depressed scar can avoid the post-surgery scar formation and adhesion, and improve the color and texture of the facial hypertrophic scar. This method can be carried out under local anesthesia, with simple procedure and exact effect.

Objective:To analyze the relationship between migration time and the prevalence of myopia of children and adolescents aged between 6 and 18 years old in Shenzhen.Methods:From April to May 2019, 26 618 children and adolescents from 14 schools in six streets of Baoan District, including Fuyong, Shajing, Xin′an, Xixiang, Songgang and Shiyan, were included in the study by using random cluster sampling method. The demographic characteristics, migration status, self-reported myopia, screen time in the last seven days, outdoor activities in the last one month and other information were collected through the questionnaire. The differences of myopia among children and adolescents with different characteristics were compared by χ 2 test, and the relationship between migration time and the prevalence of myopia was analyzed by multivariate unconditional logistic regression model. Results:The age of 26 618 study participants was (12.37±3.49) years old, and the overall prevalence of myopia was 49.4%. Multivariate logistic regression analysis showed that after controlling for relevant confounding factors, compared with migrant children and adolescents of migrant workers who migrated for 1-2 years, those of migrant workers who had migrated for more than 6 years had a higher risk of myopia [ OR (95% CI): 1.48 (1.14-1.92)]. After being grouped by phase of school, in the lower grade group of primary school, the children and adolescents of migrant workers who had migrated for more than 6 years had a higher risk of myopia compared with those of migrant workers who migrated for 1-2 years [ OR (95% CI): 1.96 (1.20-2.74)]. In the high school group, compared with the children and adolescents of migrant workers who migrated for 1-2 years, those of migrant workers who had migrated for 3-5 years and ≥6 years had a higher risk of myopia [ OR (95% CI): 6.03 (1.29-28.15) and 6.52 (1.51-28.11), respectively]. Conclusion:The migration time is related to the prevalence of myopia of the children and adolescents of migrant workers.

Objective: To describe the epidemiological characteristics and clinical manifestations of the 2019 coronavirus disease (COVID-19) in pediatric patients, and to provide data support and decision-making basis for the prevention and control of COVID-19. Methods: Cases of children aged 0-17 years reported by provincial health commissions in Anhui, Shandong, Zhejiang and Henan provinces were collected to analyze their spatial, temporal, and demographic distribution. Results: By 24:00 on February 6, 2020, a total of 107 pediatric patients had been reported in the four provinces, accounting for 3.8% (107/2 808) of the total cases reported in the four provinces during the same period. Anhui, Shandong, Zhejiang and Henan provinces had 25, 25, 28 and 29 cases, respectively. Cases ranged in age from 5 days after birth to 17 years, with a median age of 8 years. Boys accounted for 58.9%. Totally 38 cases had a history of sojourn in Wuhan or Hubei, 63 cases had a history of exposure to confirmed cases, and 6 cases with unknown exposure history. A group of 52 family clustering were found in 107 cases. All cases presented mild symptoms, no serious and no death. Conclusion Children were also susceptible to the COVID-19. Before February 2, the index pediatric cases were mainly the first generation cases, and after February 3, these pediatric cases were mainly the secondary-generation cases and those who had close contact with confirmed cases. The monitoring of children with secondgeneration cases and close contact with COVID-19 cases were valued.

We used the epidemic data of COVID-19 published on the official website of the municipal health commission in Anhui province. We mapped the spatiotemporal changes of confirmed cases, fitted the epidemic situation by the population growth curve at different stages and took statistical description and analysis of the epidemic situation in Anhui province. It was found that the cumulative incidence of COVID-19 was 156/100 000 by February 18, 2020 and the trend of COVID-19 epidemic declined after February 7, changing from J curve to S curve. The actual number of new cases began to decrease from February 2 to February 4 due to the time of case report and actual onset delayed by 3 to 5 days.