Objective:To investigate the dosimetric characteristics of intensity modulated proton therapy (IMPT) and photon volumetric modulated arc therapy (VMAT) in typical head and neck malignant tumors.Methods:Three types of typical head and neck tumors (nasopharyngeal carcinoma, parotid gland carcinoma, laryngeal carcinoma) treated at Shandong Cancer Hospital and Institute from December 2023 to December 2024 were taken as research subjects. IMPT and VMAT radiotherapy plans were created according to clinical prescription requirements of target and organs at risk limits respectively. The conformity index (CI), homogeneity index (HI) and gradient index (GI) for target coverage of two radiotherapy plans were evaluated for 3 patients, as well as the dosimetric indicators of organs at risk.Results:The CI of IMPT for nasopharyngeal carcinoma, parotid gland carcinoma and laryngeal carcinoma were 0.70, 0.72 and 0.67, respectively. The HI were 0.11, 0.08 and 0.08, respectively. The GI were 3.08, 2.49 and 3.75, respectively. The CI of VMAT plans were 0.77, 0.82 and 0.91, respectively. The HI were 0.12, 0.10 and 0.04, respectively. The GI were 3.67, 2.63 and 3.45, respectively. The results showed that CI of IMPT plan was slightly lower than that of VMAT plan, and HI of IMPT plan was comparable to that of VMAT plan, the GI of the IMPT plan for patients with nasopharyngeal carcinoma and parotid gland carcinoma was lower than that of the VMAT plan, and the GI of the IMPT plan for patient with laryngeal carcinoma was higher than that of the VMAT plan, and all were within the clinically acceptable range. The IMPT plan has demonstrated significant dose advantages in the treatment of nasopharyngeal carcinoma, parotid gland carcinoma and laryngeal carcinoma. For patient with nasopharyngeal carcinoma, the IMPT plan reduced the D max of the left and right crystals by 54.1% and 50.4%, respectively, compared to VMAT plan, and reduced the D mean of the oral and laryngeal tissues by 40.5% and 49.6%, respectively. For patient with parotid gland carcinoma, IMPT plan reduced the D max of the brainstem and spinal cord by 66.2% and 40.5%, respectively, compared to VMAT plan. For patient with laryngeal carcinoma, IMPT reduced spinal cord D max by 77.0%, while thyroid cartilage D mean increased by 8.0% compared to VMAT plan. For the additional dose in the patients' body, taking the absolute volumes occupied by the prescribed dose areas of 10%, 30%, and 50% in the patients' body as examples, IMPT plan of nasopharyngeal carcinoma patient decreased by 29.7%, 29.6%, and 34.9% compared to VMAT plan, respectively. IMPT plan of parotid gland carcinoma patient decreased by 61.0%, 39.7%, and 17.4% compared to VMAT plan, respectively. IMPT plan of laryngeal carcinoma patient decreased by 63.9%, 31.7%, and 4.1% compared to VMAT plan, respectively. Conclusions:Compared with VMAT plan, IMPT plan can effectively reduce the irradiation dose of most organs at risk near the target of head and neck tumors, but the dose of string organs close to the target area may be higher, which needs attention.

Objective:To build an experimental curriculum system of Oral Preventive Medicine with the goal of improving the job competence of oral medical students.Methods:By establishing knowledge modules, adjusting the experimental content, integrating teaching methods, and improving the comprehensive assessment system of teaching, the teaching reform is carried out in the experimental teaching of Oral Preventive Medicine for undergraduates from 2016 to 2017 in the Department of Stomatology at Zhuhai Campus of Zunyi Medical University.Results:The experimental curriculum system and teaching evaluation system of Oral Preventive Medicine with the goal of improving the job competence of medical students have been established. Cultivate students' independent learning ability and innovative and practical spirit, guide undergraduates to participate in social services, enhance the sense of social responsibility, and integrate theoretical education, ability training and quality education.Conclusions:Explore the new model of experimental oral medicine teaching, initially build the experimental curriculum system of Oral Preventive Medicine with the goal of job competence, promote the transformation of undergraduate teaching concept, deepen the connotation of teaching, and improve the depth and breadth of the teaching of Oral Preventive Medicine.

In recent years,natural antimicrobial biomaterials have received widespread attention due to their rich sources,broad anti-microbial spectrum,high antimicrobial activity,good biocompatibility,etc.They play an important role in caries prevention and treat-ment by inhibiting the formation of biofilm and removing the formed biofilm.In this paper,we summarize the inhibitory effects of differ-ent natural antimicrobial biomaterials on Streptococcus mutans,the main caries-causing organism,and its biofilm,with a view to provi-ding theoretical references for caries prevention and treatment.

In recent years,natural antimicrobial biomaterials have received widespread attention due to their rich sources,broad anti-microbial spectrum,high antimicrobial activity,good biocompatibility,etc.They play an important role in caries prevention and treat-ment by inhibiting the formation of biofilm and removing the formed biofilm.In this paper,we summarize the inhibitory effects of differ-ent natural antimicrobial biomaterials on Streptococcus mutans,the main caries-causing organism,and its biofilm,with a view to provi-ding theoretical references for caries prevention and treatment.

Objective:To build an experimental curriculum system of Oral Preventive Medicine with the goal of improving the job competence of oral medical students.Methods:By establishing knowledge modules, adjusting the experimental content, integrating teaching methods, and improving the comprehensive assessment system of teaching, the teaching reform is carried out in the experimental teaching of Oral Preventive Medicine for undergraduates from 2016 to 2017 in the Department of Stomatology at Zhuhai Campus of Zunyi Medical University.Results:The experimental curriculum system and teaching evaluation system of Oral Preventive Medicine with the goal of improving the job competence of medical students have been established. Cultivate students' independent learning ability and innovative and practical spirit, guide undergraduates to participate in social services, enhance the sense of social responsibility, and integrate theoretical education, ability training and quality education.Conclusions:Explore the new model of experimental oral medicine teaching, initially build the experimental curriculum system of Oral Preventive Medicine with the goal of job competence, promote the transformation of undergraduate teaching concept, deepen the connotation of teaching, and improve the depth and breadth of the teaching of Oral Preventive Medicine.

The application of Pseudomonas aeruginosa-mannose-sensitive hemagglutinin(PA-MSHA)in the field of an-titumors has been increasing.PA-MSHA has been found to promote tumor cell apoptosis,inhibit tumor cell invasion and migration,differentiation,and change drug resistance and epithelial-mesenchymal transformation(EMT)by inhibiting the EGFR pathway.Meanwhile,PA-MSHA also enhances the immune killing and inhibition of macrophages and T cells to tumor cells through toll-like receptors(TLRs).In this paper,we reviewed the reported anti-tumor mechanism and clinical application of PA-MSHA,suggesting that PA-MSHA may alter the glycosylation of EGFR and TLR proteins by acting on the regulatory process of the cellular mannosy-lation process.PA-MSHA can act on cell membrane proteins,including more receptors with high-mannosylation of signaling path-ways.Elucidating the deep relationship between PA-MSHA and mannosylation is of great significance for the mechanism research and clinical application of PA-MSHA.

BACKGROUND:In consideration of the food safety and ecological safety of transgenic plants,the retention of marker genes is the primary safety issue affecting transgenic plants. OBJECTIVE:Based on the principle of immune caries prevention,our research team successfully constructed the plant anti-caries vaccine fusion gene expression vector pCAMBIA-E8-APB-DOCK8 for these two caries causing virulence factors surface protein and glucosyltransferase,which provides a basis for the research and development of transgenic plant vaccine. METHODS:In this study,the selective marker genes Km and GUS in the plant caries vaccine fusion gene expression vector pCAMBIA-E8-APB-DOCK8 were removed by DNA recombination technology through a series of steps such as DNA fragment separation,connection,transformation,clone detection,and sequencing. RESULTS AND CONCLUSION:The efficiency of marker gene removal was 99%.This study has laid a good experimental foundation for the safe production of transgenic plant vaccine against dental caries,and also provided ideas for the construction of other plant vaccine vectors.

BACKGROUND:Fluorosis is a disorder of enamel development caused by long-term intake of large amounts of fluoride during enamel development. OBJECTIVE:To further explore the molecular mechanism of dental fluorosis formation by screening the differentially expressed genes associated with calcium homeostasis in ameloblasts by transcriptome sequencing technology. METHODS:LS8 cells were treated with 0,0.4,0.8,1.6,3.2 and 6.4 mmol/L sodium fluoride(NaF)for 24,48 and 72 hours to observe the effects of different concentrations of NaF on the morphology,cell activity and intracellular Ca2+ concentration of LS8 cells.The differentially expressed genes were screened by transcriptome sequencing and validated. RESULTS AND CONCLUSION:After 24 hours of treatment,the cells treated with 0,0.4,and 0.8 mmol/L NaF were in good growth condition,with increased cell number and clear cell outline.When the NaF concentration was≥1.6 mmol/L,the cells were gradually shrunken and became smaller and the number of cells decreased with the increase of NaF concentration.After 48 and 72 hours of treatment,the number of cells increased in the 0,0.4 mmol/L NaF groups,while gradually decreased in the 0.8,1.6,3.2 mmol/L NaF groups,with rounded and smaller cell morphology.The cells in the 6.4 mmol/L NaF group were shrunken,rounded and suspended in the medium,with almost no adherent cells.When treated with the same concentration of NaF,LS8 cells were in optimal growth after 24 hours of treatment.Results from cell counting kit-8 assay showed that when treated with the same concentration of NaF,the cell activity decreased with the increase of treatment time;when the treatment time was the same,the cell activity decreased with the increase of NaF concentration.After 24 hours of treatment,the intracellular Ca2+ concentration increased with the increase of NaF concentration.Transcriptome sequencing analysis identified genes involved in the regulation of cellular calcium homeostasis:Hsp90b1,Canx,Calr,and Hspa5 that were significantly upregulated(P＜0.05)and Cacna1a that was significantly downregulated(P＜0.05).To conclude,the inhibitory effect of NaF on LS8 cell proliferation may be related to the abnormal increase in intracellular Ca2+ concentration,and the mechanism may be caused by the upregulation of the expression of protein processing and synthesis pathways Hsp90b1,Canx,Calr,and Hspa5 and the downregulation of the expression of calcium signaling pathway Cacna1a.

Objective To understand the use situation of Rush among the men who have sex with men(MSM)in Chongqing City and its influencing factors,so as to provide a basis for the formulation of relevant prevention and control measures.Methods The cross-sectional survey was adopted.The MSM population in Chongqing City were recruited through the network recruitment and referral of social organizations to conduct an anonymous electronic questionnaire survey to obtain the information such as demographic characteristics,sexual partners and sexual behavior characteristics in the past 6 months,Rush use,HIV and syphilis antibody testing.The X2 test and non-conditioned multi-factor Logistic regression analysis were used to analyze the in-fluencing factors of Rush use.Results A total of 494 MSM were surveyed,the Rush usage rate was 22.1％.The results of the multi-factor logistic regression analysis showed that the age of first time homosexuality be-havior＜18 years old(OR=2.715,95％CI:1.353-5.451),unprotected homosexual anal intercourse in near-ly 6 months(OR=2.237,95％CI:1.355-3.693),having multiple same-sex partners in nearly 6 months(OR=3.610,95％CI:1.449-8.993),same-sex casual partners in the nearly 6 months(OR=3.734,95％CI:2.221-6.280)were the risk factors for MSM using Rush.Conclusion The RUSH use rate among the MSM population in Chongqing City is high.The targeted intervention measures should be carried out,especially to strengthen the propaganda and education of the population who first have homosexual behavior under 18 years old,have unprotected homosexual anal intercourse in the nearly 6 months,have multiple homosexual perma-nent partners in the last 6 months,and have homosexual temporary partners,in order to reduce the use rate of Rush and thereby reduce the risk of HIV infection and transmission in this population.

Objective To investigate the clinical effect of lithium disilicate glass ceramic cantilever resin-bonded fixed partial dentures(CRBFPDs)on single anterior tooth loss to provide a reference for the selection of restoration methods for single anterior tooth loss.Methods This study was reviewed and approved by the Ethics Committee,and informed consent was obtained from the patients.Forty-two patients with less than two anterior teeth with monomaxillary loss were included in this study.After 6 months,1 year,2 years,and 3 years,the aesthetic and functional effects of the restorations and the periodontal health status were evaluated,and the visual analog scale(VAS)was used to assess pa-tient satisfaction.Results During the observation period,the connector fractured in one case within 3 months.One case had debonded within 2 years.The aesthetic restoration effect of all lithium disilicate glass ceramic CRBFPDs was categorized as Class A.The periodontal health was good,there was no clinical absorption in the soft and hard tissues of the abutment or subbridge,periodontal status according to the evaluation indices was classified as class A,and the total satisfaction rate of the patient was 100%.Conclusion For single anterior tooth loss patients,lithium disilicate glass ceramic cantilever resin-bonded fixed partial denture can achieve the restoration effect of less invasion,better adhesion,aesthetics,comfort and good biocompatibility.With high patient satisfaction,it can be considered an ideal restoration method for replacing a single anterior tooth.