Objective:To evaluate the translucency,opalescence and fluorescence reflection of 6 light-cured resin composites. Methods:Disks of 6 resin composites including Filtek Supreme XT-YT(XT),Filtek Supreme XT-A3B(3M),Clearfil Majesty-A3 (MJ),Gradia Direct-A3(GC),Venus-A3(VE)and Charisma Diamond-A3(CA)were prepared in the diameter of 9 mm with the thickness 2.0 mm.PR-650 spectral scanning colorimeter was used to measure and caculate translucency parameters(TP),opal-escence parameter(OP)and fluorescence reflection(FL)and to draw the fluorescence reflection curves.Results:Except XT and MJ,TP value of other resin composites were in the range of natural tooth.Only OP value of XT was in the range of natural tooth en-amel.FL value of XT was close to that of natural tooth dentin.Fluorescent peak wavelength of GC,MJ,VE and CA were in the range of natural tooth,but fluorescent peak height was higher than that of natual tooth.TP was positively correlated with OP(r =0.85,P <0.05).There was no statistic correlation between TP and FL,between OP and FL.Conclusion:The 6 resin composites can simulate optical property of natual tooth,but the opalescence of resin composites is defective.

Objective: To construct a novel tissue engineering complex, BMSCs sheet-RADA16 scaffold, by combining cell sheet and self-assembled peptides.. Methods: The self-assembled peptide RADA16 scaffold was wrapped with the BMSCs cell sheet. The morphology of the cells and the complex were observed by SEM and confocal laser microscopy, and the proliferation of cells was assessed by CCK-8. The osteogenic differentiation of BMSCs was examined by detection of related gene expression with RT-PCR. Results: Compared with the BMSCs cell sheet, the numbers of cells on RADA16 scaffold growth rapidly at 3 rd-8 th day, and BMSCs were more on the scaffold than those on the cell sheet (P＜0. 05) . RT-PCR results showed that the expression level of osteogenesis-related genes was higher in the complex (P＜0. 05) . Conclusion: BMSCs Sheet-RADA16 Scaffold may promote proliferation and osteogenic differentiation of BMSCs.

Osteosarcoma is a malignant tumor with extreme invasiveness and metastasis as well as dismal prognosis. It is critical to rapidly find a unique therapy strategy capable of significantly improving the prognosis of osteosarcoma. Tumor immunotherapy has the potential to reawaken the immune system, restart and sustain the tumor-immune cycle in the body, resulting in the death of tumor cells. CD8+ CTL, CD4+ T cells, NK cells and NKT cells all play critical roles in tumor immunity, while humoral immunity may not only inhibit tumor growth but also enhance it. Researchers have devised various strategies to boost the immune system in recent years based on tumor immune response studies. This paper highlights and examines osteosarcoma immunotherapy from two perspectives: (1) boosting the response of patient's own immune system to the tumor; (2) exogenously improving the patient's immunological function.

Objective To investigate the prevalence of insomnia in college students and analyze the correlation between insomnia and perceived stress. Methods A cluster sampling method was used to investigate the prevalence of insomnia and stress levels in 3702 college students using Insomnia Severity Index (ISI) and Perceived Stress Scale-10 (PSS-10). Results Insomnia was detected in 31.4％ of the college students, and the symptoms were more severe in male students (t=2.047, P=0.041) and in those with poorer family economic conditions (F=20.423, P<0.001). Insomnia was positively correlated with perceived stress, perceived distress, and perceived coping ability, with correlation coefficients of 0.42, 0.38, and 0.31, respectively (P<0.001). The students with higher levels of perceived stress had higher insomnia scores (F=203.03, P<0.001) and higher detection rate of insomnia (x2=359.784, P<0.001), and those with moderate or severe insomnia also had higher levels of perceived stress (F=293.569, P<0.001). The types of perceived stress among college students included incontrollable (15.3％), nervous (8.3％), vulnerable (23.0％) and the relaxed types (53.5％). The incontrollable type was associated with the highest insomnia scores, followed by the nervous type and susceptible type, and the relaxed type had the lowest insomnia scores (F=185.969, P<0.001). The prevalence rates of insomnia in students with the 4 types of perceived stress were 57.3％, 43.3％, 39.3％, and 18.7％, respectively (x2=368.876, P<0.001). Conclusion There is a close correlation between perceived stress and insomnia, and identification of the high-risk population for insomnia from the perspectives of perceived stress level and perceived stress type can facilitate the management and prevention of insomnia.

Objective To investigate the prevalence of insomnia in college students and analyze the correlation between insomnia and perceived stress. Methods A cluster sampling method was used to investigate the prevalence of insomnia and stress levels in 3702 college students using Insomnia Severity Index (ISI) and Perceived Stress Scale-10 (PSS-10). Results Insomnia was detected in 31.4％ of the college students, and the symptoms were more severe in male students (t=2.047, P=0.041) and in those with poorer family economic conditions (F=20.423, P<0.001). Insomnia was positively correlated with perceived stress, perceived distress, and perceived coping ability, with correlation coefficients of 0.42, 0.38, and 0.31, respectively (P<0.001). The students with higher levels of perceived stress had higher insomnia scores (F=203.03, P<0.001) and higher detection rate of insomnia (x2=359.784, P<0.001), and those with moderate or severe insomnia also had higher levels of perceived stress (F=293.569, P<0.001). The types of perceived stress among college students included incontrollable (15.3％), nervous (8.3％), vulnerable (23.0％) and the relaxed types (53.5％). The incontrollable type was associated with the highest insomnia scores, followed by the nervous type and susceptible type, and the relaxed type had the lowest insomnia scores (F=185.969, P<0.001). The prevalence rates of insomnia in students with the 4 types of perceived stress were 57.3％, 43.3％, 39.3％, and 18.7％, respectively (x2=368.876, P<0.001). Conclusion There is a close correlation between perceived stress and insomnia, and identification of the high-risk population for insomnia from the perspectives of perceived stress level and perceived stress type can facilitate the management and prevention of insomnia.

In the battle of COVID-19 epidemic prevention and control in China, the "countermarching people" faced up to all difficulties and went forward one after another to the forefront of anti-epidemic. Many vivid figures and examples have aroused our feelings and thoughts on life. Under the background of this special period, medical colleges should take the COVID-19 prevention and control as an opportunity to enrich the contents of bioethics education, blend in patriotism education, social responsibility education, medical moral education, and life and death culture education. By strengthening the construction of teaching staff, attaching importance to the integration of teaching contents, optimizing teaching carriers, expanding practical activities and recommending online teaching resources, the teaching reform of bioethics education is explored in order to enhance the effectiveness and sustainability of bioethics education and moral education.

Objective:To elucidate the molecular mechanism(s) by which methyl salicylate enhances the skin de-livery of herbal ingredients with diverse lipophilicity.Methods:The toxicity of methyl salicylate on skin cell lines was evaluated using the MTT assay.The Franz diffusion cell method was used to measure the permeability enhancing activities of methyl salicylate for five herbal ingredients with a range of lipophilicities.The interaction between methyl salicylate and the stratum corneum (SC) was observed by using an infrared spectroscopy technique.Moreover,the solu-bilities and SC-vehicle partition coefficient were determined to monitor the impact of methyl salicylate on the drug thermodynamic activities and partition into the SC layer,respectively.Results:Compared with azone (1-dodecylazacycloheptan-2-one),methyl salicylate showed lower toxicity to skin cells in terms of the ICso values.The in vitro skin permeation studies showed that methyl salicylate could greatly improve the cumulative amounts or steady state flux of the selected model drugs with the exception of osthole,which indicated that methyl salicylate was prone to promote the skin delivery of hydrophilic drugs.The Fourier transform infrared spectroscopy studies revealed that methyl salicylate mainly interacted with SC lipids,leading to the disruption of the orderly arrangement of the SC.In addition,methyl salicylate had no obvious effect on the drug thermodynamic activity and partition into the SC.Conclusion:Methyl salicylate could effectively promote the skin delivery of relatively hydrophilic in-gredients in externally used traditional Chinese medicines (TCM) without obvious cytotoxicity.

Red blood cells(RBCs)are the primary mediators of oxygen transport in the human body,and their function is mainly achieved through conformational changes of hemoglobin(Hb).Hb is a tetramer composed of four subunits,with HbA being the predominant Hb in healthy adults,existing in two forms:tense state(T state)and relaxed state(R state).Endogenous regulators of Hb conformation include 2,3-diphosphoglyceric acid,carbon dioxide,protons,and chloride ions,while exogenous regulators include inositol hexaphosphate,inositol tripyrophosphate,benzabate,urea derivative L35,and vanillin,each with different mechanisms of action.The application of Hb conformational regulators provides new insights into the study of hypoxia oxygen supply issues and the treatment of sickle cell disease.

Objective To provide the experimental basis for the subsequent genetic diversity research through establishing and optimizing the inter-simple sequence repeat PCR (ISSR-PCR) reaction system of Gnaphalium affine. Methods The single-factor experimental method and full experimental method were used to optimize the ISSR-PCR reaction system of Gnaphalium affine. Under the optimal system, after screening primers and corresponding annealing temperatures, the systematic feasibility was verified. Results The optimal ISSR-PCR reaction system was consisted of 10 μl Premix Taq DNA polymerase, 0.3 μmol/L primer, 10 ng DNA template, and sterilized water added to 20 μl. Finally, 10 primers were screened from 100 universal primers, and verification results indicated the system had high stability, good reproducibility, and the selected primers had good polymorphism. Conclusion The ISSR-PCR amplification system of Gnaphalium affine was established for the first time and the primers with appropriate annealing temperatures were filtered out, which provided a reference for the subsequent genetic diversity research of Gnaphalium affine.

【Objective】 To investigate the relationship between maternal oral health behavior during pregnancy and premature birth. 【Methods】 A total of 248 preterm and 700 non-preterm pregnant women who delivered in Northwest Women’s and Children’s Hospital in Shaanxi Province from January to December 2022 were included in case group and control group, respectively. General demographic characteristics and oral health behavior during pregnancy were collected by questionnaires, and the oral health impact profile-14 (OHIP-14) was used to assess the oral health related life quality of pregnant women. Logistic regression model was used to analyze the relationship between maternal oral health behavior during pregnancy and premature birth. 【Results】 During pregnancy, maternal frequent eating after brushing teeth (OR=1.62, 95% CI: 1.03-2.57), unused fluoride toothpaste (OR=2.03, 95%CI: 1.25-3.05), late visit to the doctor for oral discomfort (OR=1.41, 95%CI: 1.02-1.96), brushing teeth less than twice one day (OR=1.77, 95%CI: 1.13-2.78) or less than 3 minutes each time (OR=1.52, 95%CI: 1.09-2.11), and elevated OHIP-14 score (OR=1.07, 95%CI: 1.04-1.10) increased the risk of premature birth. 【Conclusion】 Poor oral health behavior during pregnancy may increase the risk of premature birth. Therefore, more efforts should be made to publicize oral health knowledge and guide pregnant women to establish good oral health habits so as to improve oral health and promote maternal and child health.