A longitudinal study on association between puberty development and thyroid function of school aged girls in Minhang District, Shanghai / 中国学校卫生

Objective@#To observe the association between puberty development and thyroid function among school-aged girls in Minhang District of Shanghai, in order to explore the effect of puberty development on thyroid function. @*Methods@#The study was based on a cohort of adolescent girls recruited in iodine-suitable areas of Minhang District, and the baseline and follow-up survey have been carried out from January to March 2019. The method of phased cluster sampling was used to select one junior high school in the east, south, north and middle of Minhang District, Shanghai, respectively. Finally, 464 new junior high school girls were included in the Cohort study for physical examination, and girls were followed up from January to March 2021. The Puberty Development Scale (PDS) was used to assess the stage of puberty. Serum thyroid stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) were determined for each participant. Thyroid homeostasis structure parameters (THSPs) was calculated. Changes of Thyroid hormones at baseline and follow-up were compared by Wilcoxon signed rank sum test. Multiple linear regression analyses were used to evaluate the associations of thyroid hormones (THs) and THSPs changes with pubertal develepment.@*Results@#Serum TSH levels of female studentds decreased significantly, while their FT3 and FT4 levels increased significantly during the study period ( Z=-10.53, -4.71, -12.46, P <0.01). In multiple linear regression analysis after adjustment for co-variables (including baseline age, change of BMI and waist circumference), FT4 and thyroid feedback quantile-based index (TFQI) in the higher puberty category scores changes (△PCS) group were further reduced compared with those in the low △PCS group ( β =-0.66, -0.55 ). Compared to the late puberty at baseline and follow-up (BLFL) group, FT4 and TFQI showed higher decline in the pre-puberty at baseline and late puberty at follow-up (BPFL) group with the pre-puberty at baseline and end of puberty at follow-up (BPFT) group ( β =-0.55, -0.44)( P <0.05). There were no association of △TSH, △FT3, △FT4/FT3 and TSH index changes (△TSHI) with △PCS or the puberty pattern.@*Conclusion@#Serum TSH decreases while serum FT3 and FT4 increase among girls during puberty. Both the initial stage and the velocity of pubertal development are related to thyroid hormone fluctuations.

Sequential treatment and prognostic factors of traumatic root fracture in permanent anterior teeth / 口腔疾病防治

@#Root fracture is a kind of dental trauma involving dentin, cementum, pulp tissue, periodontal membrane ligament and even the surrounding alveolar bone. It occurs frequently between the ages of 10-20, mostly in the area of the maxillary anterior teeth with high aesthetic requirements. The treatment goal for root fracture in permanent teeth is to maintain the physiological and functional integrity of the tooth as much as possible and to reduce the incidence of complications. Clinicians usually classify the affected teeth according to the position of the root fracture, including the apical, mid-root, cervical-mid-root and cervical segments, since it determines the treatment plan and the prognosis of the affected teeth. CBCT examination can avoid misdiagnosis and missed diagnosis of root fracture to the greatest extent. The sequential treatment plan of root fracture after permanent anterior tooth trauma includes initial emergency treatment, pulp vitality monitoring and complication management during follow-up. Emergency treatment mainly includes local anesthesia and repositioning, if displaced, the coronal segment of the tooth as soon as possible. Then, after checking its position radiographically, adjustment occlusion and flexible splinting for 4 weeks (4 months for cervical root fracture). The process of root fracture repair includes many tissues and is affected by many clinical factors. Timely and standardized treatment and close follow-up according to the Dental Trauma Guideline guarantee a good prognosis of root fracture. The closer the root fracture line is to the apex, the higher the survival rate is. In addition to the location of the root fracture line, the prognosis is affected by many other clinical factors, such as the displacement of the coronal fragment of the root fracture, the pathological state of the dental pulp, patient age, developmental stage of the root, timely and good replacement of the root fracture, splinting method, and the presence of other dental trauma complications. Pulp vitality should be monitored regularly, and root canal therapy of the coronal segment should be carried out only when infection of the pulp is established. This article reviews the classification, diagnosis, emergency treatment, sequential follow-up treatment, and prognostic assessment of root fracture trauma to provide suggestions for clinicians to manage root fracture trauma in permanent teeth.

Dynamics of parenting styles of adolescent students from the perspective of intergenerational conflict / 中国学校卫生

Objective@#To explore dynamics of parenting styles of adolescents from 1999 to 2019 from the perspective of intergenerational conflict, to provide support for family education and adolescent healthy development.@*Methods@#Using a multistage stratified cluster random sampling method, the unified questionnaire was administered to 2 590 students in the same sampling junior and senior high schools in 1999, 2009, and 2019 using the Egna Minnen av Barndoms Uppfostran own memories of parental rearing practices in childhood(EMBU).@*Results@#Overall there were differences in the nine factors of parenting styles across generations ( F = 12.07-72.52, P <0.01), with decreasing ratings of warmth and understanding of father and mother (F1, M1), over interference of father (F3) over generations(F1:46.72±9.41, 45.87±11.33, 43.61±11.27; M1:51.56±9.38, 51.03±11.59, 46.23± 12.27 ; F3:19.03±4.00, 18.29±4.32, 17.95±4.51), and all other parenting styles rated higher in 2019 than in 2009 and 1999(except for the over protection and over interference of mother, and punishment, firm control of mother). Parenting styles across generations (except for the rejection and denial of father among girls) showed gender difference.The overall gender trend coincided with the total population trend. Parenting styles across generations varied significantly among middle and high school students( F =3.92-47.27, P <0.05 ), changes in F1 and F3 factors coincided with the overall decreasing trend. Factor analysis showed that parenting styles could be classified into two dimensions, with varied factor loading across generation.@*Conclusion@#Intergenerational decreases in parental emotional warmth and paternal interfering are observed in a sex and grade specific manner. Based on the diversity of needs and population differentiation, optimal intervention for comprehensive health development of adolescents are in great need to keep pace with the times and promoting the high quality development of adolescents.

Antibiotic resistance spectrum and genetic characteristics of MDRSA nasal isolate among primary school students / 中国学校卫生

Objective@#To investigate the antibiotic resistance spectrum and genetic characteristics of multidrug-resistant Staphylococcus aureus(MDRSA) nasal isolate among primary school students, and to provide a scientific basis for the prevention and control of masal MDRSA resistance and the selection of clincal drugs in children.@*Methods@#Antibiotic susceptibility experiments were performed on all SA isolates of 1 705 primary school students from 8 primary schools in Guangzhou selected by using multistage cluster stratified sampling method. MDRSA antibiotic susceptibility spectrum was analyzed, and the resistant, virulence and immune evasion cluster(IEC) genes detected by polymerase chain reaction(PCR).@*Results@#The prevalence of MDRSA nasal carriage was 20.76%(354/1 705), and the proportion of multidrug resistance among SA isolates was 96.20%(354/368). The predominant resistant antibiotics of MDRSA isolates were penicillin(99.72%), erythromycin(96.33%), clindamycin(90.96%) and teicoplanin(90.11%). Notably, 240(67.80%, 240/354) MDRSA isolates were resistant to more than six antimicrobial categories. And the predominant detection rates of resistant genes were BlaZ(92.66%), Tet(M)(49.72%), virulence genes Tst(25.42%) and IEC genes Sak(92.09%), Hlb(61.58%).@*Conclusion@#We found high prevalence of nasal colonization MDRSA from healthy children. Moreover, MDRSA isolates has a high resistant rate to multiple antibiotics, and the proportion of resistant to ≥6 antimicrobial categories is high.

Contamination prevalence and drug resistance spectrum of MRSA from classrooms in Guangzhou primary schools / 中国学校卫生

Objective@#To investigate the distribution and drug resistance situation of staphylococcus aureus (SA) and methicillin-resistant staphylococcus aureus (MRSA) from the classroom environments in primary schools of Guangzhou.@*Methods@#The air and the surfaces of door handles, desks, chairs, light switches and floor were sampled in the classrooms of 8 primary schools selected through stratified clustering method in Guangzhou from May to June, 2016. SA and MRSA were isolated and identified, and drug sensitivity tests were conducted.@*Results@#A total of 760 samples were collected, the detection rate of SA and MRSA were 8.8% and 4.2%, respectively. There were statistically significant differences in the detection rate of staphylococcus aureus among different sampling sites(P<0.01).Detection of SA and MRSA on the floor,light’s witches and surface of deskes was both above 6.0%. The multiple drug resistance rate of MRSA was up to 100.0%, and the main resistance mode was Penicillin-Erythromycin-Rifampin-Tetracycline-Teicolanin.@*Conclusion@#MRSA can be detected in air, door handles, desk surface, chair surface, light switch and floor of primary schools. Relevant administration departments should pay attention to the environments health of Guangzhou primary schools.

Contamination state of Staphylococcus aureus from toilets of primary schools in Guangzhou / 中国学校卫生

Objective@#To investigate the contamination, antimicrobial resistance and virulence genes of S. aureus from toilets of primary schools in Guangzhou.@*Methods@#The surface samples of toilets were collected from eight primary schools in Guangzhou from May to July 2016. The standard microbiological assays, disk diffusion methods and PCR technique were used for the isolation and identification, antimicrobial resistance and virulence genes of S. aureus .@*Results@#The contamination rate of S. aureus and MRSA was 6.25% and 3.13%, respectively. There was significant difference in the contamination rate of S. aureus among different sampling sites ( χ 2=15.15, P <0.01) and the highest contamination rate was on the ground (15.00%).The most predominant antibiotic for S. aureus was penicillin (100.00%) and the proportions of resistant to teicoplanin, erythromycin,rifampicin, clindamycin and linezolid were more than 75.00%.The multidrug resistant rate of S. aureus was 85.00%.The detection rate of virulence genes of S. aureus was sea (50.00%), tst (30.00%), etb (15.00%), eta (10.00%), seb (10.00%) and pvl (5.00%), respectively.@*Conclusion@#The contamination rate of S. aureus from toilets of primary schools in Guangzhou is in a lower level among similar researches. However, the contamination of MRSA is serious, which accounts for half of S. aureus . In addition, S. aureus isolates show high multi-drug resistant rate and high detection rate of virulence genes.

Finite element analysis of torque control efficiency of a homemade four-curved auxiliary arch for anterior teeth / 口腔疾病防治

Objective @#To analyze the initial displacement of the upper central incisor and stress distribution of periodontal ligament under different torque values of upper incisors under the action of a four-curved auxiliary arch to provide a reliable basis for the safety of clinical application of four-curved auxiliary arches.@*Methods @# A three-dimensional finite element model for torque control of upper anterior teeth with a homemade quadrilateral auxiliary arch was established. Four different states were analyzed: molar ligation without extraction space (group A), microimplant ligation without extraction space (group B), molar recovery with extraction space closure (group C) (the adductive traction force was set at 115 g) and microimplant recovery with extraction space closure (group D) (the adductive traction force was set at 115 g). When four types of torque (0.5 N, 1.0 N, 1.5 N, and 2.0 N) were applied. The initial displacement of upper central incisors and the stress distribution of periodontal ligament in 16 groups (A1-A4, B1-B4, C1-C4, D1-D4) were observed.@*Results @#Under different conditions, as the strength of the four-curve auxiliary arch increases, the maxillary anterior teeth has crown labial inclination and a root lingual inclination. The displacement of the incisor tip increases with the increase in the loading force of the torque auxiliary arch, and the displacement of the incisor root apex increases as the force increases. The difference in incisor-apex displacement distance in A1-A4, B1-B4, C1-C4, D2 and D4 groups increased as the torque force increases, while the difference between the D3 group and D1 and D2 groups decreased slightly. The stress of the cervical periodontal ligament of the upper central incisor did not exceed the stress of the periodontal ligament in the following groups: A1, A2, B1, B2, B3, C1, C2, D1, and D2. The stress of the lip side of the upper central incisor did exceed the stress of the periodontal ligament in the following groups: A3, A4, B4, C3, C4, D3, and D4. In other words, when using the four-curved auxiliary arch as an implant anchorage, the force applied in the absence of extraction space should not exceed 1.5 N, and the force applied in the adduction of extraction space should not exceed 1.0 N. When using the nonimplant anchorage, the force applied in the absence of extraction space and the adduction of extraction space should not exceed 1.0 N. In addition, the range of force should not exceed the maximum stress of the periodontal ligament in the cervical region such that the effective and safe torque movement can be achieved. Under other stress conditions, the stress of the labial and cervical periodontal ligament of the upper central incisor exceeded the stress value (2.6 × 10-2MPa). The stress value of periodontal ligament was 2.6 × 10-2MPa in all groups.@*Conclusion@#A four-curved auxiliary arch has a significant effect on the upper anterior teeth, and the use of microimplants can better control root movement such that the crown of upper central incisors cannot be excessively lip inclined.

Effects of different developmental patterns on thyroid morphological changes among children in pre-puberty and puberty / 中国学校卫生

Objective@#To investigate the effects of different developmental patterns on the increases of thyroid volume in children from different genders and periods, and to explore whether there is a synergistic effect on the initiation of puberty in girls, so as to provide a theoretical basis for reducing the risk of thyroid abnormalities in adulthood.@*Methods@#A multi-stage cluster sampling was used to select a primary school in Minhang District of Shanghai, Haimen City of Jiangsu Province and Yuhuan city of Zhejiang Province. A total of 784 children aged 8-10 years old were included in "8-10 years school-aged children cohort". At the same time, a total of 491 girls aged 11-13 years were included in the "11-13 years adolescent girls cohort". The content of survey on follow-up was consistent with the one on baseline. B-ultrasonography was used to measure thyroid volume. The physical development indexes such as height (H), weight (W) and waist circumference (WC) were measured. The morning urine samples were collected and the urinary iodine content was detected. The changes of body mass index (BMI), waist circumference (WC), and thyroid volume (V) were calculated (d BMI, d WC, and d V, respectively). According to the changes of BMI and WC, the subjects were classified into four types of developmental changes, namely "B-LW-L (low d BMI, low d WC)" "B-LW-H (low d BMI, high d WC)" "B-HW-L (high d BMI, low d WC)" and "B-HW-H (high d BMI , high d WC)". Results In partial correlation analysis, thyroid volume was significantly correlated with BMI and WC at baseline or follow-up(P<0.05). The changes of thyroid volume in 8-10 years old boys were related to the changes of BMI and WC (P<0.05), the changes of thyroid volume in 8-10 year old girls were only associated with the changes of WC (P=0.03), and no association was found in 11-13 year old girls(P>0.05). In multivariate logistic regression analysis, after adjusting for baseline age, region, and differences of urinary iodine, the risk of thyroid volume increasing in B-HW-H was 2.70 times (95%CI=1.29-5.66) higher than that of B-LW-L in boys aged 8-10 years; among girls aged 11-13 years, the risk of thyroid volume increasing in B-LW-H, B-HW-L and B-HW-H were 2.46 times (95%CI=1.31-4.61), 2.16 times (95%CI=1.15-4.03) and 1.79 times (95%CI=1.07-2.99), respectively; there was no interaction between menarche age and developmental pattern on thyroid volume change trend (P=0.49).@*Conclusion@#The thyroid volume in children and adolescents increases with the development of physical development. Different developmental patterns and estrogens have certain effects on thyroid morphological changes. To avoid obesity in childhood (especially with central obesity), timely identify and effectively intervene thyroid morphological abnormalities in childhood，and to reduce the risk of thyroid diseases in adulthood.

Signal Peptide and Denaturing Temperature are Critical Factors for Efficient Mammalian Expression and Immunoblotting of Cannabinoid Receptors / 华中科技大学学报（医学）（英德文版）

Many researchers employed mammalian expression system to artificially express cannabinoid receptors,but immunoblot data that directly prove efficient protein expression can hardly be seen in related research reports.In present study,we demonstrated cannabinoid receptor protein was not able to be properly expressed with routine mammalian expression system.This inefficient expression was rescued by endowing an exogenous signal peptide ahead of cannabinoid receptor peptide.In addition,the artificially synthesized cannabinoid receptor was found to aggregate under routine sample denaturing temperatures (i.e.,≥95℃),forming a large molecular weight band when analyzed by immuno-blotting.Only denaturing temperatures ≤75℃ yielded a clear band at the predicted molecular weight.Collectively,we showed that efficient mammalian expression of cannabinoid receptors need a signal peptide sequence,and described the requirement for a low sample denaturing temperature in immuno-blot analysis.These findings provide very useful information for efficient mammalian expression and immuno-blotting of mcmbrane receptors.