Objective: To analyze the current status of latent tuberculosis infection (LTBI) among freshmen in boarding middle schools in Longgang District, Shenzhen, so as to provide reference for formulating tuberculosis prevention and control strategies in the next stage. Methods: Data for tuberculosis health examination conducted among primary and secondary school students in Longgang District of Shenzhen in September 2022 to May 2023 were utilized to analyze the latent tuberculosis infection rate, and to explore the differences in latent tuberculosis infection rate among different grades, school nature, school categories and school levels. Results: The latent tuberculosis infection rate among freshmen in boarding secondary schools in Longgang District, Shenzhen in 2022 was 2.45%. The infection rate among full middle school (6.45%) and high school (3.37%) were higher than that in boarding junior high school (0.28%), nine year education school (0) and twelve year education school (1.00%) ( P <0.01). Moreover, the infection rate of high school freshmen (2.68%) was higher than that of bording junior high school (0.33%), and the rate of public schools (2.87%) and municipal schools (3.24%) were higher than those of private schools (1.78%) and distric-level schools (2.13%) respectively, with statistical significance observed for all differences( χ 2=43.58, 25.15, 22.69, P <0.01). Conclusions The latent tuberculosis infection rate among new boarding secondary students is relatively low in Longgang District of Shenzhen. However, the infection rate is higher in high school, public and municipal school. School should fully guarantee sports participation of students, enhance students awareness of tuberculosis through health knowledge lectures, and reduce the incidence of tuberculosis among students.

An efficient vacuum suction system is a necessary prerequisite for the smooth operation of the oral diagnosis and treatment.During the use of the dental units,there is often a situation of vacuum suction weakness,resulting in the inability to discharge the mixture of blood,saliva,dental tissue and other mixtures in time,which affects the doctor's treatment field and increases the risk of aspiration pneumonia and cross-infection in patients.The working principle,pipeline system,filters and other aspects of the vacuum suction system that may affect the suction efficiency was analyzed.The causes and solutions of vacuum suction weakness were discussed,and operation suggestions were proposed to ensure the safe and effective use of equipment and ensure the safety of diagnosis and treatment.

Objective To study the antioxidant activity and free radical scavenging kinetics of Chrysanthemi flos stems and leaves,and online screen the active components related to free radical scavenging.Methods Using DPPH method and ABTS method the antioxidant activity of extracts from Chrysanthemi flos stems and leaves was observed,and the effects of different influencing factors,such as drug concentration,reaction temperature and reaction time on free radical scavenging rate were compared,the half scavenging rate(IC50)was determined.The flavonoids,such as luteolin glucuronic acid,luteolin,and caffeic acid,phenolic acids such as chlorogenic acid,neochlorogenic acid,cryptochlorogenic acid,isochlorogenic acid A,B,and C in the samples before and after the reaction were chosen as indexes,and their contents were determined by HPLC.Results The drug concentration,reaction temperature and reaction time could affect the scavenging rate of DPPH free radical and ABTS.The IC50 of DPPH and ABTS were 0.395 mg·mL-1 and 2.039 mg·mL-1 respectively.After reaction with DPPH and ABTS,the contents of the analytes above all decreased significantly,which suggested that,the components above might be the antioxidant components in Chrysanthemi flos stems and leaves.Conclusions Chrysanthemi flos Stems and leaves have good free radical scavenging activity.In this study,the kinetic characteristics of scavenging DPPH and ABTS free radicals in Chrysanthemi flos stems and leaves were preliminarily clarified,and the active components were found out.It provides an experimental basis for the future comprehensive development of Chrysanthemi flos stems and leaves.

Objective:To investigate soft-and hard-tissue changes after simultaneously labial and lingual augmented corticotomy in patients with insufficient alveolar bone thickness of lower anterior teeth both in labial and lingual side during orthodontic treatment.Methods:From January 2021 to June 2022, 10 patients [2 males and 8 females, (26.2±3.1) years old] who received orthodontic and orthognathic combined treatment from the Fourth Clinical Division, Peking University School and Hospital of Stomatology were selected. The alveolar bone thickness of lower anterior teeth both in labial and lingual side in these patients was less than 0.5 mm according to cone-beam CT examination before or during treatment, and 60 lower anterior teeth were included. The 10 patients were treated with simultaneously labial and lingual augmented corticotomy. The differences in gingival recession, papilla index and the differences in labial and lingual alveolar bone thickness of lower anterior teeth were compared.Results:Six months after surgery, the alveolar bone thicknesses at the 4 mm under cemento-enamel junction (CEJ), 8 mm under CEJ and at the apical level [labial side: (1.02±0.39), (2.22±0.89) and (4.87±1.35) mm; lingual side: (1.07±0.46), (2.31±1.04) and (3.91±1.29) mm] were significantly higher than that before surgery [labial side: (0.02±0.09), (0.06±0.21) and (2.71±1.33) mm]; lingual side: (0.14±0.29), (0.40±0.52) and (2.13±1.02) mm] ( P<0.001), respectively. The increases in alveolar bone thickness of central incisors [apical level on labial side: (2.53±1.20) mm, 8 mm under CEJ on lingual side: (2.27±1.24) mm, apical level on lingual side: (2.66±1.49) mm] and lateral incisors [apical level on labial side: (2.42±1.30) mm, 8 mm under CEJ on lingual side: (2.28±0.92) mm, apical level on lingual side: (1.94±1.15) mm] were significantly higher than that of canines [apical level on labial side: (1.52±1.47) mm, 8 mm under CEJ on lingual side: (1.17±1.09) mm,apical level on lingual side: (0.74±1.37) mm] ( P<0.01). There were no significant differences in the degree of gingival recession [labial side before surgery: (0.72±0.88) mm, lingual side before surgery: (0.80±1.09) mm; labial side 6 months after surgery: (0.72±0.81) mm,lingual side 6 months after surgery: (0.89±0.21) mm] and gingival papilla index [before surgery: 1.00(0.75, 2.00); 6 months after surgery: 1.00(1.00, 2.00) ] between pre-operation and 6 months after surgery ( P>0.05). No serious complications occurred. Conclusions:The method used in this article for simultaneously labial and lingual augmented corticotomy was safe and feasible. This surgery has positive clinical significance for the stability of the periodontal tissue in orthodontic treatment for patients with alveolar bone thickness less than 0.5 mm of lower anterior teeth both in labial and lingual side.

The lung is an important organ in systemic toxicity test of medical devices and is significant in safety evaluation. Based on the authors' understanding of medical devices, this study provides a brief analysis of the lung examination and common problems in systemic toxicity, so as to provide references for the pre-clinical safety evaluation of medical devices. It should be noted that a reasonable risk assessment should be made after comprehensive assessment for specific medical device products.
Equipment Safety ; Humans ; Lung ; Risk Assessment

Objective:To investigate the clinical effect of hearing aid combined with cognitive rehabilitation training in the treatment of dementia with hearing loss.Methods:Forty-six cases of dementia patients with hearing loss in Dalian Municipal Central Hospital Affiliated of Dalian Medical University from September 2019 to September 2020 were divided into two groups by random number table method. The treatment group received cognitive rehabilitation training assisted by sound amplifier, while the control group only received cognitive rehabilitation training for 7 weeks. Before and after treatment, questionnaires were used to evaluate the training effect of patients, including MMSE, HAMA, HAMD and ADL, and satisfaction questionnaire was used to evaluate the satisfaction of caregivers.Results:After treatment, the MMSE score of the treatment group was significantly higher than that of the control group: (20.22 ± 3.38) scores vs. (19.89 ± 3.10) scores ( P<0.05), and HAMA and HAMD were significantly lower than those of the control group: (11.43 ± 5.07) scores vs. (11.83 ± 4.79) scores, (8.39±3.37) scores vs. (9.67 ± 5.34) scores ( P<0.05); there was no difference in activities of daily living between the treatment group and the control group ( P>0.05); the caregiver satisfaction of the treatment group was significantly improved, compared with that of the control group ( P<0.05). Conclusions:Hearing assisted cognitive training can improve the cognitive function of patients with hearing-impaired dementia, promote mental and emotional stability, and improve the feelings of caregivers; we emphasize the importance of hearing evaluation for the elderly with dementia, and the importance of cognitive rehabilitation training with hearing assistance.

To explore the technical process and the therapeutic effect of using sequential surgical guide with independent intellectual property rights assisting immediate implantation and restoration of the full arch, with the support from the periodontal splint for mobile supporting teeth, patients with severe periodontitis who planned to undergo immediate full arch implantation were recruited from August 2019 to December 2020 at the Department of Prosthodontics, Department of Periodontology, Department of Implantology and First Clinical Division, Peking University School and Hospital of Stomatology. Through the procedure of collecting preoperative maxillofacial data, making systematic diagnostic design, making periodontal splints fixation, producing surgical guide, and carrying out guided surgery for full arch immediate implantation, eight cases were included. By registering the postoperative cone-beam CT (CBCT) with the preoperative data, the difference between the actual three-dimensional position of the implants and the virtual design was observed, and the accuracy of the implant placement position guided by the sequential guide was statistically analyzed using SPSS 25.0 software. Analysis indicators include coronal and apical global displacement, coronal horizontal and vertical displacement, apical horizontal and vertical displacement, and angular deviation. Results revealed that the 8 patients [2 males and 6 females, aged (49.0±9.3) years (38-65 years)] of recruited cases included 7 cases of maxilla and 1 cases of mandible. A total of 48 implants, of which 44 implants were placed upright and 4 were placed tilted, 16 implants in the anterior region and 32 implants in the posterior region. No guide plate fracture or damage to important anatomical structures were reported. The overall displacement at the coronal point [(0.83±0.48) mm] and the global displacement at the apical point [(1.36±0.57) mm] were within the clinically acceptable safety range, and the horizontal displacement and vertical displacement at the coronal point, horizontal displacement and vertical displacement at the apical point, and the angle deviation of implants axial have no statistic significant difference in the anterior and posterior region ( P>0.05). Periodontal splints combined with sequential surgical guides to assist patients with severe periodontitis for immediate full arch implantation and immediate restoration can expand the indications of guide assisted implant surgery. It meets the safety requirements in clinical applications.

Objective:To investigate the status quo of human resources of dentists who deal with periodontal disease in Beijing area through an online survey, which may hopefully provide a preliminary basis for the decision-making of administrative departments and the formulation of periodontal professional development plan.Methods:The dentists who deal with periodontal disease at least half a day per week in Beijing area were investigated. A questionnaire was designed by the chairman of the Periodontology Committee of Beijing Stomatological Association. The questionnaire was sent to and finished by the dentists via "WenJuanXing" online survey software. The contents of the survey included general condition, the property of practice unit, title and position of the dentist, membership of professional society, time and content of periodontal treatment, adoption of new technology and new method of periodontal therapy during the past one year, status of periodontal treatment in the local population and reasons, understanding and influencing factors of periodontal professional development.Results:A total of 1 255 dentists completed the survey, who came from all 16 districts in Beijing, mainly Haidian, Chaoyang, Dongcheng and Xicheng Districts [The total percentage of these four main districts was 70.3% (882/1 255)]. The mean age of the dentists was (36.1±8.3) years. Among the dentists, 71.1% (892/1 255) were females, 88.1% (1 106/1 255) got a Bachelor′s degree or above. It was estimated that 35.4% (444/1 255) of the dentists had received standardized periodontal training ever. The percentage of dentists carrying out new technology in the past one year was as high as 68.1% (855/1 255). There were only 163 periodontal specialists (13.0%) out of the dentists in the survey. Only 15.9% (200/1 255) of the dentists routinely performed periodontal surgery. The majority of the dentists [82.8% (1 039/1 255)] were from the state-owned hospitals. Fifty-four point seven percemt (686/1 255) of the dentists thought that lack of knowledge was the main reason why the general public failed to receive periodontal treatment. As for the biggest bottleneck affecting periodontal professional development, fifty-one point zero percent (640/1 255) of the dentists attributed it to the public neglect.Conclusions:The periodontal practitioners in Beijing are young, highly educated, unevenly distributed in 16 districts and mostly females. State-owned oral health institutions are an important force in periodontal diagnosis and treatment services in Beijing. The number of periodontal specialists need to be improved. Promotion of standardized periodontal surgery and the popularization of healthcare knowledge on periodontal disease should also be the focus in the future.

Objective:To investigate the clinicopathological and molecular biological characteristics of patients with plasma cell tumor.Methods:The data of bone marrow fluid, bone marrow tissue, peripheral blood and urine specimens of 84 patients with plasma cell tumor from January 2016 to October 2018 in Shanxi Provincial People's Hospital were collected. Bone marrow fluid was examined by using bone marrow smear, karyotype analysis, fluorescence in situ hybridization (FISH), immunophenotyping, and next-generation sequencing (NGS). In addition to the observation of cell morphology, peripheral blood together with urine specimens was also determined by using immune-fixation electrophoresis and free light chain examination. Bone marrow tissue was used to observe the structure and fibrosis of bone marrow, and relevant histochemistry and immunohistochemistry was also performed.Results:Among 84 patients with plasma cell tumor, 2 patients (2.4%) were monoclonal gammopathies of un-determined significance (MGUS), 78 patients (92.8%) were multiple myeloma (MM) (38 cases were IgG Kappa type, 33 cases were IgG Lambda type, 2 cases were IgA Kappa type, 1 case was IgA Lambda type, 3 cases were light chain type, 1 case was non-secretory type), 3 cases (3.6%) were Waldenstrom macroglobulinemia (WM), and 1 case (1.2%) was non-secretory myeloma (NSM). The proportion of abnormal plasma cells detected by bone marrow smear was 0.132-0.676 in 81 patients, and the proportion of abnormal monoclonal plasma cells detected by flow cytometry (FCM) was 1.1%-52.4% in 79 patients. Immunohistochemistry and FCM detection of bone marrow showed positive or weak positive results of CD38 and CD138. Complex karyotype was rare in karyotype analysis. FISH examination showed IGH isolation in 24 patients (28.6%) and gene detection showed 1 case was positive IGH-CCND1 and 1 case was positive IGH-MAF; 1 case of free light chain examination was positive. The positive rate of NGS was lower.Conclusion:Most plasma cell tumors are IgG type, followed by IgA type. Light chain type of plasma cell tumors is rare, and IgM type and non-secretory type are extremely rare. The morphological manifestations of bone marrow smear cytology in different clone types are different.

Objective:To compare the short-term clinical outcomes of robotic distal pancreatectomy(RDP) with laparoscopic distal pancreatectomy(LDP).Methods:PubMed, Embase, Cochrane library, Wanfang data, CNKI were searched systematically.Studies that compared short-term clinic outcomes between RDP and LDP groups were included. Observation indicators include: operation time, intraoperative blood transfusion rate, spleen preserving rate, spleen vessels preserving rate, conversion rate to open surgery, complication rate, severe complication rate, pancreatic fistula rate, severe pancreatic fistula rate, length of hospital stay, etc. The Meta-analysis was performed by using RevMan5.3.Results:Eleven non-randomized controlled trials with 791 patients meet the inclusion criteria.This Meta-analysis shows: compared with LDP group, RDP group was associated with higher spleen preserving rate ( OR=2.32, 95% CI: 1.07-5.04, P=0.03), higher splenic vessels preserving rate ( OR=3.07, 95% CI: 1.10-8.57, P=0.03), lower conversion rate to open surgery ( OR=0.58, 95% CI: 0.35-0.97, P=0.04), shorter hospital stay ( MD=-2.42, 95% CI: -4.30 --0.55, P=0.01), longer operative time ( MD=27.11, 95% CI: 9.06-45.16, P<0.01). There was no significant difference in overall complications, severe complications, pancreatic fistula, severe pancreatic fistula, and transfusion rate between the two groups. Conclusions:RDP showed a slight advantage in short-term outcomes, and it is worthy of applying in large medical center. Further studies on the long-term outcomes of these surgical techniques are required.