Objective:To prepare novel dental composite resins using zinc(Zn)-and nitrogen(N)-modified titanium dioxide(TiO?)nanoparticles(NPs)and mesoporous alumina(Al?O?,r type,20 mm)NPs as reinforcing fillers,systematically evaluating their antibacterial activity,mechanical strength,basic performance,and biosafety to obtain the dental composite resins with excellent antibacterial activity and mechanical strength.Methods:Zn-N-TiO? NPs and mesoporous Al?O? NPs were added into a resin matrix at varying mass ratios to prepare five composite resins:control group(no filler),group 0(Zn-N-TiO?∶Al?O?=1∶0),group 1(Zn-N-TiO?∶Al?O?=1∶1),group 2(Zn-N-TiO?∶Al?O?=1∶2),and group 3(Zn-N-TiO?∶Al?O?=1∶3).Plate colony counting method was used to detect the number of adhered bacteria on composite resin surfaces in various groups and calculate the antibacterial rate;scanning electron microscope(SEM)was used to observe the morphology of adhered bacteria in various groups;universal testing machine was used to measure flexural strength(FS)and elastic modulus(EM)of composite resins in various groups;SEM was used to observe fracture surface morphology of composite resins in various groups;microhardness tester was used to determine Vickers microhardness of the composite resins in various groups;Fourier transform infrared spectroscope was used to detect double bond conversion rate(DC)after 20 s photocuring and calculate curing depth;water contact angle meter was used to measure water contact angle(WCA),water sorption property(WSP),and water solubility level(WSL)of composite resins in various groups;cell counting kit-8(CCK-8)method was used to evaluate relative growth rate(RGR)of the mouse fibroblast L-929 cells cultured in composite resin extracts on days 1,3,and 5 and determine in vitro cytotoxicity grade.Results:The plate colony counting results showed that compared with control group,the colony counts on agar plates in the other groups were significantly reduced,with group 1 showing the lowest count.The SEM images results showed densely distributed and morphologically intact Streptococcus mutans in control group;small clusters of bacteria with depressed cell membranes in group 0 and group 3;sparsely distributed bacteria with obvious membrane shrinkage and cytoplasmic leakage in group 1 and group 2.No statistically significant difference in colony counts was found between group 1 and group 2(P>0.05),but both were lower than the other groups(P<0.05).All the composite resins in experimental groups exhibited>85%antibacterial rates,with group 1 and group 2 exceeding 99%.The composite resins in group 0 showed the lowest FS.With addition of mesoporous Al?O?,the FS of the composite resin in group 1 and group 2 were significantly increased,with the composite resin in group 2 showing the highest FS among all groups.Although the FS of the composite resin in group 3 was lower than that in group 2,but it remained higher than other groups(P<0.05).The SEM images results showed that in control group,the smooth-surfaced sillicon dioxide(SiO?)particles exhibited clear fracture interfaces with resin matrix,with>50%particle exposure;the composite resin in group 0 showed similar morphology and large Zn-N-TiO? agglomerates with tight filler-matrix bonding;the composite resin in group 1,2,and 3 showed resin adhesion to SiO? surfaces(<50%particle exposure)and uneven fracture surfaces.Fractured SiO? spheres were observed in group 2.Filler distribution was uniform in group 1 and group 2,while the minor NP agglomeration occurred in group 3.The composite resin in control group showed the lowest EM.The EM was significantly improved in experimental groups,with group 3 having the highest value.Group 0 exhibited the lowest Vickers microhardness,showing statistically significant differences among other groups(P<0.05).The Vickers microhardness of the composite resion was gradually increased with the rising of Al?O? content.The resins in group 2 and group 3 achieved>45 HV hardness,representing increases of 29.73%and 33.82%compared with control group,and 51.34%and 56.28%compared with group 0.No significant differences in DC of the composite resin were found among groups(P>0.05).The depth of cure for all composite resin groups exceeded 4 mm,with no significance differences observed between various groups(P>0.05).The composite resin in group 0 showed the smallest WCA.The hydrophobicity of the composite resion was increased with the rising of Al?O? content,but all the WCA values remained<80°.The composite resin in group 3 had the largest WCA without statistical significance compared with group 2(P>0.05).Filler incorporation reduced the water sorption/solubility.The composite resin in the CCK-8 assay results showed the composite resins in all groups had RGR>75%,meeting in vitro safety standards.Conclusion:Reinforcing fillers impart superior antibacterial activity and mechanical properties to composite resins.Under experimental conditions,group 2 composite resin achieves optimal comprehensive performance in antibacterial efficacy and mechanical strength,demonstrating promising clinical application potential.

Immune factors play an important role in recurrent spontaneous abortion(RSA),and immune imbalance affects embryo implantation,growth,and development.There is currently no consensus on the etiology and pathogenesis of RSA caused by immune factors.Based on the theory of latent toxic in TCM and combined with the pathological mechanism of the dynamic changes of immune abnormal substances in the body,this article proposed that latent toxic is the key cause of RSA caused by immune factors.Furthermore,it expounded the pathogenic characteristics of latent toxic:combination of heat and blood stasis hidden in the womb,and latent toxic plays a role in embryo formation under qi deficiency conditions.It is established that latent toxin stagnation in the membrane is the pathogenic mechanism.Moreover,this article revealed the variable pathological changes such as the blockage of the inner membrane system and the outer membrane system.Treatment should be based on the basic methods of tonifying qi and nourishing blood,tonifying kidney to secure the Thoroughfare Vessel,clearing heat and cooling blood,promoting blood circulation and removing blood stasis.This article could provide a theoretical basis for TCM syndrome differentiation and treatment of RSA caused by immune factors.

Gelatin microspheres were discussed as a scaffold material for bone tissue engineering, with the advantages of its porosity, biodegradability, biocompatibility, and biosafety highlighted. This review discusses how bone regeneration is aided by the three fundamental components of bone tissue engineering-seed cells, bioactive substances, and scaffold materials-and how gelatin microspheres can be employed for in vitro seed cell cultivation to ensure efficient expansion. This review also points out that gelatin microspheres are advantageous as drug delivery systems because of their multifunctional nature, which slows drug release and improves overall effectiveness. Although gelatin microspheres are useful for bone tissue creation, the scaffolds that take into account their porous structure and mechanical characteristics might be difficult to be created. This review then discusses typical techniques for creating gelatin microspheres, their recent application in bone tissue engineering, as well as possible future research directions.
Tissue Engineering/methods* ; Tissue Scaffolds/chemistry* ; Gelatin/chemistry* ; Microspheres ; Bone and Bones ; Porosity

Objective: To understand epidemiology and associated factors of delay for tuberculosis in schools of Jiaxing, and to provide basis for the strategy of pulmonary tuberculosis prevention and control in schools. Methods: Based on the Tuberculosis Management Information System, the information of school tuberculosis cases in Jiaxing from 2011 to 2020 was collected, and the epidemiological characteristics were analyzed by descriptive epidemiology. Results: A total of 436 student pulmonary tuberculosis patients and 46 teacher pulmonary tuberculosis patients were reported in Jiaxing from 2011 to 2020. The average annual incidence rate in teachers (10.70/100 000) was higher than that in students (6.16/100 000) ( χ 2=13.06， P <0.05). The incidence rate of school pulmonary tuberculosis (6.59/100 000) was lower than that in the whole population (37.91/100 000) ( χ 2=184.63， P ＜ 0.05 ). The school pulmonary tuberculosis patients mainly occurred from March to May, accounted for 11.62%,11.00%,9.96% respectively. The incidence rate of school pulmonary tuberculosis patients in county level was lower than in urban district in 2012, and higher than in urban district in 2017 and 2020( χ 2=4.61，5.72，4.02， P <0.05). Most student pulmonary tuberculosis patients aged from 15 to 19 years old, the percentage was higher in males(90) than in females(75) in students. The reported incidence rate of pulmonary tuberculosis in primary school and junior high school teachers was higher than that in the same students ( χ 2=24.34， 14.87 ， P ＜0.05). Passive case finding including clinical symptomatic inspection and referrals was the main way to find cases. The detection delay rate was 34.23%. Conclusion Early detection, prompt and scientific treatment, shortening the delay time were key to prevent the spread of the school tuberculosis. It is of great significance to reduce the occurrence of clustering in outbreak and public health emergency.