Abstract With one of the highest rates of Internet penetration in the world, cyberbullying among students in Republic of Korea is typical and complex. The article interprets the characteristics of comprehensive prevention and treatment strategies aimed at cyberbullying among Republic of Korea students, and summarizes Republic of Korea s experience in building "government regulation with laws and policies in parallel, home-school governance with two way educational intervention, and social cogovernance with diversified collaborative empowerment". In recent years, comprehensive prevention and treatment of cyberbullying among students in China has achieved certain results, but there are still problems. It can learn from Republic of Korea s experience, optimize prevention and treatment system of China, improve laws and regulations, innovate technology empowerment systems, and give play to cultural education mechanisms, so as to promote the comprehensive prevention and treatment of cyberbullying among students in China.

Objective: To analyze the correlation between the levels of vitamin A, vitamin D, vitamin E with body fat mass percentage(FMP) as well as lifestyle factors among primary school students, so as to provide references for exploring the vitamin nutritional status of primary school students and its potential influencing factors. Methods: From September 1 to October 30, 2021, a cluster sampling method was used to select 750 thirdgrade students from eight primary schools in Luohu District, Shenzhen. Their body composition was measured, and blood samples were collected to detect the serum levels of vitamin A, vitamin D, and vitamin E using a mass spectrometer. Dietary and exercise habits were collected through questionnaires. Mann-Whitney U test and Kruskal-Wallis H rank sum test were used for inter group comparisons, spearman correlation was used for correlation analysis,and Logistic regression model was used to analyze the association between lifestyle and vitamin content. Results: The overall level of vitamin A in school aged children was 0.4 (0.4, 0.5) mg/L, with a deficiency rate of 0 and a marginal deficiency rate of 5.1%; the level of vitamin D was 26.0 (22.0, 30.0) ng/mL, with a deficiency rate of 0.4% and an insufficiency rate of 12.7%; the content of vitamin E was 11.8 (10.1, 13.5) mg/L, with an insufficiency rate of 0.8%. Spearman correlation analysis showed that vitamin A was positively correlated with FMP in the total population, boys, girls, and normal weight population ( r =0.18, 0.18, 0.20, 0.10), and vitamin D was positively correlated with FMP in the total population and obese population ( r =0.08,0.16)(all P <0.05). Logistic regression analysis showed that marginal deficiency of vitamin A was associated with consumption of animal, snack, and dairy/egg/bean foods ( OR =0.45, 0.55, 0.59); whether vitamin D was deficient was influenced by gender ( OR =2.65) and exercise ( OR = 1.96 ) (all P <0.05). Conclusion Vitamin A, vitamin D and vitamin E levels are associated with body fat percentage, with significant variations in vitamin status among individuals of different body types, necessitating targeted supplementation.

Performance appraisal of public hospitals have given a guidance for the development of public hospitals at all levels.A Class A tertiary hospital reviewed the problems in the development of the hospital at the present stage and focused on the following four aspects:①insufficient fine management;②No clear orientation of discipline development;③The bottleneck of the improvement of medical operation efficiency;④New challenges in the reform of payment mode.The tertiary hospital launched a fine management practice in May 2022,in order to solve the problems by taking the Department of Surgery as a pilot area,laying the foundation for fine management through information system construction,improving the efficiency of medical operation through management process optimization,improving the overall competitiveness of disciplines through the construction of sub-specialty and Discipline Alliance and adjusting the performance appraisal index system to play the role of performance incentives.The measures effectively improve the overall capacity and efficiency of hospital medical services and help the hospital to achieve high-quality development.

Objective:To describe the prevalence of daytime nap habit in participants of the China Kadoorie Biobank (CKB) study, across 10 study regions and explore its correlation with prevalence of major chronic diseases.Methods:Participants with a self-reported pre-diagnosis of any cancer at baseline survey were excluded. Logistic regression models were used to analyze the differences in study regions and age distribution of the prevalence daytime nap habit, and its correlation with the prevalence of diabetes, hypertension, coronary heart disease (CHD), stroke, chronic obstructive pulmonary disease (COPD), and chronic liver diseases.Results:Among 510 145 participants, 39.9% had daytime nap habit in summer and 20.8% had daytime nap habit all the year round. Urban-rural differences were observed in the prevalence of summer nap habit and perennial nap habit. Daytime nap in summer was common in rural areas and Suzhou, with prevalence ranged from 32.9% to 73.3%. Haikou and Liuzhou had higher prevalence of perennial nap (60.4% and 63.3%). The proportion of people with daytime nap habit all the year round increased with age ( P for trend <0.001), the proportion was highest in those aged 70- years (31.9%). Daytime nap habit in summer was positively correlated with the prevalence of diabetes, hypertension, CHD and chronic liver disease with OR of 1.10 (95% CI: 1.07-1.14), 1.03 (95% CI:1.02-1.05), 1.07 (95% CI: 1.02-1.12) and 1.07 (95% CI:1.00-1.14), respectively. Daytime nap habit all the year round was positively correlated with the prevalence of diabetes, hypertension, CHD, stroke, COPD and chronic liver disease with OR of 1.33 (95% CI: 1.29-1.37), 1.11 (95% CI: 1.09-1.13), 1.39 (95% CI: 1.33-1.45), 1.33 (95% CI: 1.26-1.41), 1.12 (95% CI: 1.08-1.16) and 1.27 (95% CI:1.18-1.37) respectively. Conclusion:There were regional and age differences in prevalence of daytime nap habit among CKB participants. Daytime nap habit, especially daytime nap habit all the year round, was positively correlated with the prevalence of major chronic diseases.

Objective:To investigate the role of folliculin in apoptosis of and chemokine secretion by melanocytes mediated by interferon-γ (IFN-γ) .Methods:Normal primary melanocytes were isolated from circumcised foreskin tissues from a healthy male child, and primary vitiliginous melanocytes were isolated from normally pigmented suction-blistered epidermis from patients with vitiligo after suction blister epidermal grafting. Western blot analysis was performed to determine the folliculin protein expression in normal primary melanocytes, primary vitiliginous melanocytes and a human primary melanocyte line PIG1. PIG1 cells stimulated with 10 ng/ml IFN-γ for 48 hours served as induction group, and untreated PIG1 cells served as control group. Real-time quantitative RCR (qRT-PCR) was performed to determine the mRNA expression of folliculin, autophagy-related microtubule-associated protein 1 light chain 3 (LC3) -Ⅱ and Beclin genes, and Western blot analysis to determine the protein expression of folliculin, Beclin1 and LC3Ⅱ/Ⅰ, as well as phosphorylation levels of adenosine monophosphate-activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR) in the above cells. Furthermore, the melanocytes stimulated with 10 ng/ml IFN-γ for 48 hours were divided into several groups: negative control group infected with an empty lentiviral vector, folliculin inhibition group infected with a folliculin-inhibiting lentivirus, autophagy enhancement group infected with a folliculin-inhibiting lentivirus followed by 2-hour treatment with a mTOR inhibitor, autophagy inhibition group infected with a folliculin-inhibiting lentivirus followed by 2-hour treatment with an AMPK inhibitor. Then, flow cytometry was conducted to detect apoptosis of PIG1 cells, and enzyme-linked immunosorbent assay to measure the concentration of chemokines CXCL10 and CCL20 in the culture supernatant of PIG1 cells in the above groups. Measurement data were compared among multiple groups by using one-way analysis of variance, and multiple comparisons were carried out by using least significant difference- t test. Results:The relative protein expression level of folliculin significantly differed among the normal primary melanocytes (0.850 ± 0.120) , primary vitiliginous melanocytes (1.507 ± 0.170) and PIG1 cells (0.697 ± 0.130; F = 50.09, P < 0.001) , and was significantly higher in the primary vitiliginous melanocytes than in the normal primary melanocytes and PIG1 cells ( t = 4.06, 5.89, respectively, both P < 0.01) . Compared with the control group, the induction group showed significantly increased relative mRNA and protein expression levels of folliculin (both P < 0.01) , but significantly decreased relative mRNA and protein expression levels of LC3Ⅱ and Beclin (all P < 0.01) ; moreover, the induction group showed significantly decreased LC3Ⅱ/Ⅰ levels (0.72 ± 0.02) and AMPK phosphorylation levels (0.714 ± 0.023) in the PIG1 cells compared with the control group (1.13 ± 0.02, 1.176 ± 0.002, t = 7.34, 6.67, respectively, both P < 0.01) , but significantly increased mTOR phosphorylation levels (1.051 ± 0.023) compared with the control Group (0.451 ± 0.016, t = 3.81, P = 0.009) . There were significant differences in the PIG1 cell apoptosis rate and concentrations of CXCL10 and CCL20 among the control group, induction group and other treatment groups (all P < 0.001) ; specifically, the PIG1 cell apoptosis rate and concentrations of CXCL10 and CCL20 were significantly higher in the induction group than in the control group, lower in the folliculin inhibition group than in the negative control group, lower in the autophagy enhancement group than in the folliculin inhibition group, and higher in the autophagy inhibition group than in the folliculin inhibition group (all P < 0.05) . Conclusions:Folliculin is highly expressed in vitiliginous melanocytes. Folliculin expression and downstream signaling pathways are regulated by IFN-γ, and folliculin may participate in IFN-γ-mediated melanocyte apoptosis and chemokine secretion via regulating autophagy.

Objective To evaluate biomechanical properties of the personalized titanium alloy short femoral prosthesis by finite element analysis. Methods Based on the validated femoral finite element model, the base of the femoral neck was simulated, and by inserting different short femoral prostheses, four total hip replacement (THR) models, namely, the SMF stem model (Model A), BE1 stem model (Model B), MINI stem model (Model C) and personalized stem model (Model D) were established, respectively. The same loads and constraints were applied to four groups of models, and the von Mises stress distribution and deformation were calculated and analyzed, so as to compare mechanical stability of each model. Results The deformation of all THR models was smaller than that of the femur model under physiological state. The deformation of Model B was close to that of Model C, and the deformation of Model A was close to that of Model D. The peak stress of Model C was higher than that of the other 3 models, reaching 9555 MPa. The overall stress trend was Model C > Model B > Model D> Model A > Model under physiological state. Conclusions The peak stress, stress distribution of personalized short femoral stem were similar to that of SMF stem, with reasonable stress distribution, small stress shielding of the proximal femur, minimum overall deformation and shear stress of the prosthesis, and its effectiveness and stability could meet the requirements of human biomechanics, which could provide references for joint surgeons and prosthesis researchers.

PLZ-NPs (PNS-lipid-zein nanoparticles) prepared by co-assembly of Panax notoginseng saponins, lecithin, β-sitosterol and zein were applied for in vitro cell experiment and oral gavage to study the protective effect of cerebral ischemia-reperfusion rats.PLZ-NPs were characterized by Malvin-particle size analyzer and transmission electron microscope (TEM), respectively. The toxicity of PLZ-NPs and free carrier were evaluated by MTT, and the uptake of nanoparticles in Caco-2 cells was analyzed by laser confocal and flow cytometry. The cerebral ischemia reperfusion rat model was established by MCAO method and then be given samples by gavage for 3 days. The brain tissues were taken to stain by 2, 3, 5-triphenyltetrazole chloride (TTC) and the biochemical indicators of MDA, inflammatory cytokines IL-1β and TNF-α, apoptosis-related proteins Bax and Bcl-2 from the harvested brain tissues were detected to evaluate the protective effect of PNS in PLZ-NPs on cerebral ischemia reperfusion. The particle size, PDI, and zeta potential of formed PLZ-NPs were (116.4 ± 0.81) nm, 0.048 and -(31.5 ± 0.31) mV, respectively. The results of MTT showed that the zein lipoprotein carrier was non-toxic to Caco-2 cells. The results of laser confocal and flow cytometry showed that FITC uptake of nanoparticles could be significantly improved in Caco-2 cells.The uptake from the nanoparticles at 4h was 1.76 times of that of the free FITC group.Compared with the model group, the TTC staining images of free drug PNS group and PLZ-NPs group showed certain reduction in the white infarct area.The contents of MDA, IL-1β, TNF-α and Bax were significantly decreased, while the content of Bcl-2 was significantly increased. Furthermore, all parameters of PLZ-NPs group showed better results than those of PNS group, and there was a significant difference (P < 0.05). All results indicated that the prepared PLZ-NPs had good stability and biological safety, and could significantly increase the uptake in intestinal epithelial cells, and effectively protect against the damage caused by cerebral ischemia reperfusion in rats.

Objective:To discussed the diagnostic value of magnetic resonance cholangiopancreatography (MRCP), and the use of laparoscopic surgery in management of patients with choledochal cyst with extrahepatic bile duct anomaly.Methods:Of 330 consecutive patients who underwent laparoscopic choledochectomy at Guangzhou Women and Children's Medical Center from January 2010 to September 2018, there were 23 patients with extrahepatic bile duct anomaly. The data of these patients were retrospectively analyzed. There were 4 males and 19 females, with an average age of 3.2 (range 0.3~9.0) years. According to whether the extrahepatic bile duct anomaly was diagnosed by preoperative MRCP, these patients were divided into the preoperative MRCP diagnosis group and the preoperative MRCP undiagnosed group. The impact of MRCP in diagnosing bile duct anomaly to prevent bile duct injury, on operation time, hospital stay and the types of extrahepatic bile duct anomaly on outcomes of laparoscopic treatment were analyzed.Results:All the 23 patients with choledochal cysts complicated by extrahepatic bile duct anomaly were confirmed at surgery. The incidence of extrahepatic bile duct anomaly was 6.97% (23/330). There were 47.8% of type II AHD (11/23); 36.8% of type III AHD (7/23); 4.3% of type IV AHD (1/23); 17.4% (4/23) of the type with communication with accessory bile duct (CABD). The preoperative MRCP diagnosis group consisted of 14 patients, while the preoperative MRCP non-diagnosis group consisted of 9 patients, including 2 patients without MRCP. The diagnostic rate of MRCP in preoperative diagnosis of extrahepatic bile duct anomaly was 66.7%(14/21). The preoperative MRCP undiagnosed group, when compared with the preoperatives MRCP undiagnosed group, had a significantly higher bile duct injury rate [preoperative MRCP diagnosis group 7.1%(1/14), preoperative MRCP non-diagnosis group 55.6%(5/9)], and a significantly longer operation time [preoperative MRCP diagnosis group(232.6±10.0) min, preoperative MRCP undiagnosed group (278.9±22.45)min], (all P<0.05). Laparoscopic surgery was completed in 22 of 23 patients. One patient was converted to open surgery. AHD reconstruction was needed in 11 patients with type II AHD and 1 patient with type IV AHD. Seven patients with type III AHD did not require any surgical intervention for the anomaly. The 4 patients with CABD underwent simple ligation. Postoperative chyloperitoneum developed in 1 patient, who successfully responded to conservative treatment. Postoperative recovery was uneventful in the remaining patients. At a median follow-up of 2 years (range 1 to 5 years), no further complications, including intrahepatic bile duct dilatation and hepatic atrophy were detected. Conclusions:MRCP was effective in preoperative diagnosis of choledochal cysts with extrahepatic bile duct anomaly. It helped to decrease intraoperation injuries to bile duct anomalies. MRCP was also useful in classifying patients with extrahepatic bile duct anomaly to better preoperatively planning of surgical treatment strategies. Laparoscopic surgery could be completed in the majority of these patients with good postoperative results.

Objective:To study the clinical characteristics of patients with severe abdominal infection and the epidemiological characteristics of pathogenic bacteria in a hospital, to provide a basis for rational use of antibiotics and reduce the drug resistance rate of pathogens.Methods:A retrospective analysis was performed on 237 patients with abdominal disease as the primary disease admitted to the surgical intensive care unit (ICU) of the First Affiliated Hospital of Guangxi Medical University from January 1st, 2017 to December 31st, 2019. They were divided into two groups according to whether abdominal infection occurred or not. The clinical features of patients in both groups were analyzed, including gender, age, acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score, chronic underlying diseases, primary abdominal site, abdominal trauma or bleeding, multiple organ dysfunction syndrome (MODS) involving organs and surgical treatment. At the same time, the bacterial origin, bacterial distribution and antibiotics sensitivity test results of patients with abdominal infection were recorded.Results:Abdominal infection occurred in 141 of the 237 patients and did not occur in the remaining 96 patients. There were no statistically significant differences between the abdominal infection group and the non-abdominal infection group in terms of gender, age, chronic underlying diseases, etiology and trauma. The APACHE Ⅱ score in the abdominal infection group was obviously higher than that of the non-abdominal infection group (24.0±8.1 vs. 17.1±5.8, P < 0.01). Incidences of abdominal bleeding, MODS involving four or more organs, surgery and the times of surgery ≥ 3 in the abdominal infection group were significantly higher than those in the non-abdominal infection group (36.2% vs. 17.7%, 20.6% vs. 1.0%, 84.4% vs. 21.9%, 9.3% vs. 0%, all P < 0.05). Among the 141 patients with abdominal infection, 107 obtained positive microbial culture results, and a total of 133 pathogenic strains were detected, including 115 strains of bacteria (86.5%) and 18 strains of fungi (13.5%). The main source of bacteria was abdominal drainage (46.1% of non-bloody specimens and 13.9% of bloody specimens). Among the 115 bacteria, Gram-negative (G -) bacteria were the most common (72.2%) and Gram-positive (G +) bacteria accounted for 27.8%. Escherichia coli and Acinetobacter baumannii were the top two G - bacteria (40.9% and 13.9%, respectively), and enterococcus faecalis accounted for the largest proportion of G + bacteria (7.8%). The pathogenic bacteria of abdominal infection were sensitive to tigacycline. Conclusions:The patients with abdominal infection in our hospital had high APACHE Ⅱ score, more organs failure and were easily complicated with intraperitoneal hemorrhage and required surgical intervention and even repeated surgery. The pathogenic bacteria in patients with abdominal infection in ICU were mainly G - bacteria, and the rate of multi-drug resistance of Acinetobacter baumannii was high. Empirical anti-infective treatment should be started as soon as possible according to the microbial spectrum of the region until the pathogenic bacteria results are obtained. Broad-spectrum antimicrobial therapy and combined antimicrobial therapy are recommended for the healthcare acquired abdominal infection in hospital.

Objective:To investigate the clinical characteristics of pediatric methicillin-resistant Staphylococcus aureus (MRSA) infection and the antibiotic sensitivity of the isolates. Methods:The clinical data of children with MRSA infection and antibiotic sensitivity of the isolates from 11 children′s hospitals in Infectious Diseases Surveillance of Paediatrics (ISPED) group of China between January 1, 2018 and December 31, 2018 were collected retrospectively. The children′s general condition, high-risk factors, antimicrobial therapy and prognosis, differences in clinical disease and laboratory test results between different age groups, and differences of antibiotic sensitivity between community-acquired (CA)-MRSA and hospital-acquired (HA)-MRSA were analyzed. The t test and Wilcoxon rank sum test were used for statistical analysis of the quantitative data and Chi-square test were used for comparison of rates. Results:Among the 452 patients, 264 were males and 188 were females, aged from 2 days to 17 years. There were 233 cases (51.5%) in the ≤1 year old group, 79 cases (17.5%) in the>1-3 years old group, 29 cases (6.4%) in the >3-5 years old group, 65 cases (14.4%) in the >5-10 years old group, and 46 cases (10.2%) in the>10 years old group. The main distributions of onset seasons were 55 cases (12.2%) in December, 47 cases (10.4%) in February, 46 cases (10.2%) in November, 45 cases (10.0%) in January, 40 cases (8.8%) in March. There were 335 cases (74.1%) CA-MRSA and 117 (25.9%) cases HA-MRSA. Among all cases, 174 cases (38.5%) had basic diseases or long-term use of hormone and immunosuppressive drugs. During the period of hospitalization, 209 cases (46.2%) received medical interventions. There were 182 patients (40.3%) had used antibiotics (β-lactams, glycopeptides, macrolides, carbapenems, oxazolones, sulfonamides etc) 3 months before admission. The most common clinical disease was pneumonia (203 cases), followed by skin soft-tissue infection (133 cases), sepsis (92 cases), deep tissue abscess (42 cases), osteomyelitis (40 cases), and septic arthritis (26 cases), suppurative meningitis (10 cases). The proportion of pneumonia in the ≤1 year old group was higher than the >1-3 years old group,>3-5 years old group,>5-10 years old group,>10 years old group (57.5% (134/233) vs. 30.4% (24/79), 31.0% (9/29), 38.5% (25/65), 23.9% (11/46), χ 2=17.374, 7.293, 7.410, 17.373, all P<0.01) The proportion of skin and soft tissue infections caused by CA-MRSA infection was higher than HA-MRSA (33.4% (112/335) vs. 17.9% (21/117), χ 2=10.010, P=0.002), and the proportion of pneumonia caused by HA-MRSA infection was higher than CA-MRSA (53.0% (62/117) vs. 42.1% (141/335), χ 2=4.166, P=0.041). The first white blood cell count of the ≤1 year old group was higher than that children > 1 year old ((15±8)×10 9/L vs. (13±7)×10 9/L, t=2.697, P=0.007), while the C-reactive protein of the ≤1 year old group was lower than the 1-3 years old group,>5-10 years old group,>10 years old group (8.00 (0.04-194.00) vs.17.00 (0.50-316.00), 15.20 (0.23-312.00), 21.79(0.13-219.00) mg/L, Z=3.207, 2.044, 2.513, all P<0.05), there were no significant differences in procalcitonin (PCT) between different age groups (all P>0.05). After the treatment, 131 cases were cured, 278 cases were improved, 21 cases were not cured, 12 cases died, and 10 cases were abandoned. The 452 MRSA isolates were all sensitive to vancomycin (100.0%), linezolid (100.0%), 100.0% resistant to penicillin, highly resistant to erythromycin (85.0%, 375/441), clindamycin (67.7%, 294/434), less resistant to sulfonamides (5.9%, 23/391), levofloxacin (4.5%, 19/423), gentamicin (3.2%, 14/438), rifampicin (1.8%, 8/440), minocycline (1.1%, 1/91). The antimicrobial resistance rates were not significantly different between the CA-MRSA and HA-MRSA groups (all P>0.05). Conclusions:The infection of MRSA is mainly found in infants under 3 years old. The prevalent seasons are winter and spring, and MRSA is mainly acquired in the community. The main clinical diseases are pneumonia, skin soft-tissue infection and sepsis. No MRSA isolate is resistant to vancomycin, linezolid. MRSA isolates are generally sensitive to sulfonamides, levofloxacin, gentamicin, rifampicin, minocycline, and were highly resistant to erythromycin and clindamycin. To achieve better prognosis. clinicians should initiate anti-infective treatment for children with MRSA infection according to the clinical characteristics of patients and drug sensitivity of the isolates timely and effectively.