OBJECTIVE To compare the short-term efficacy of autologous frozen tragus perichondrium and fresh perichondrium in repairing tympanic membrane perforations,and to explore the clinical application value of autologous frozen tragus perichondrium.METHODS Twenty-five patients with bilateral tympanic membrane perforations from March 2021 to October 2023 were selected,including 7 males and 18 females.Bilateral tympanoplasty was completed in stages.The initial operation was set as the control group,in which the ventral perichondrium of the tragus was used for tympanoplasty,and the dorsal perichondrium of the tragus was reserved and stored at-80℃ultra-low temperature in a sterile container.The second operation was set as the observation group,in which the thawed frozen perichondrium was used for contralateral tympanoplasty.The differences in the healing rate of tympanic membrane,postoperative hearing,operation time and surgical bleeding volume were compared between the two groups.RESULTS All patients were followed up for three months.The success rate of tympanic membrane healing in the observation group was 96%(24/25),and that in the control group was 92%(23/25).There was no statistically significant difference between the two groups(χ2=0.36,P>0.05).The operation time and surgical bleeding volume of patients in the observation group were lower than those in the control group[(48.64±4.64)min vs.(67.92±5.69)min,(5.32±1.54)ml vs.(9.65±1.73)ml],and the differences were statistically significant(t=13.93,t=12.09,P all<0.05).The postoperative air conduction hearing thresholds and air-bone conduction gap of the two groups of patients were lower than those before operation(all P<0.05).There was no difference in air conduction hearing threshold,bone conduction hearing threshold and air-bone conduction difference between the groups(all P>0.05).CONCLUSION The application of autologous frozen tragus perichondrium has effectively shortened the operation time of the contralateral ear,avoided the trauma caused by taking materials again,and has the characteristics of minimally invasive and high efficiency.The method is feasible and the curative effect is accurate.

AIM:To observe the effect of folic acid(FA)on C2C12 myoblast proliferation and differentia-tion,and to explore its mechanism.METHODS:During the proliferation stage,C2C12 myoblasts were treated with vari-ous concentrations of FA(0,2.5,5,10 and 20 μmol/L).The cell status was observed under a microscope,cell viability was detected using the MTT method,and cell proliferation was assessed using the EdU method.In the differentiation stage,C2C12 cells were divided into control(Ctrl)group(0 μmol/L FA)and FA group(10 μmol/L FA).On day 2 or 4 of differentiation,immunofluorescence staining and Western blot were employed to detect the expression of myoblast differen-tiation-related proteins,myoblast determination protein 1(MyoD),myogenin(MyoG)and myosin heavy chain(MyHC).The myotubule formation in each group was analyzed.On day 4 of differentiation,C2C12 cells were treated with FA for 0,1,3 and 6 h,and the protein levels of p-JNK,JNK,p-p38 MAPK and p38 MAPK at each time point were detected by Western blot.Additionally,C2C12 cells after 4-day differentiation were divided into Ctrl group,FA group,FA+ SP600125(specific inhibitor of JNK)group,and FA+SB203580(specific inhibitor of p38)group.The cells in FA+ SP600125 and FA+SB203580 groups were treated with 10 μmol/L SP600125 or SB203580 for 1 h,followed by treatment with 10 μmol/L FA for 24 h.The cells in FA group were treated with 10 μmol/L FA for 24 h,while the cells in Ctrl group were left untreated.The protein levels of p-JNK,JNK,p-p38 MAPK,p38 MAPK and MyHC were detected by Western blot.RESULTS:(1)Compared with 0 μmol/L FA group,the number of the cells in other concentration groups in-creased,cell viability was raised(P＜0.05 or P＜0.01),and the rate of EdU positive cells increased(P＜0.05).(2)Com-pared with Ctrl group,the expression levels of MyoD,MyoG and MyHC in FA group were increased(P＜0.05),and the myotube fusion index was raised(P＜0.05 or P＜0.01).(3)Compared with 0 h group,the ratios of p-JNK/JNK and p-p38 MAPK/p38 MAPK were elevated after FA treatment for 1,3 and 6 h(P＜0.05 or P＜0.01),and showed a trend of gradual increase with the extension of treatment time.(4)After FA treatment,the ratios of p-JNK/JNK and p-p38 MAPK/p38 MAPK,and the expression of MyHC were elevated(P＜0.01).Treatment with SP600125 decreased the ratio of p-JNK/JNK and the expression of MyHC(P＜0.05),while SB203580 intervention cut down the ratio of p-p38 MAPK/p38 MAPK and the expression of MyHC(P＜0.05 or P＜0.01).CONCLUSION:Folic acid can promote the differentiation of C2C12 myoblasts by activating the JNK/p38 MAPK signaling pathway.

Objective To know the attitude about palliative care and its influence factors in nurses.Methods Interviewed 8 nurses deeply by qualitative research to know their attitude about pallia-tive care.Results 4 theme,including 9 subtheme were found: nurses' negative emotion caused by job; imperfect of special organization and criterion; characteristics of nursing work.Conclusions Hospital managers should enhance training of nurses' coping capacity with bad feelings, death education and culti-vation of empathy; improve medicare system;develop palliative care routine ; establish palliative care orga-nizations, and relieve nurses' job burden and increase wages.

Objective To investigate the effect of water soluble extracts of some traditional Chinese herbs on hair growth of pig hair follicle in vitro. Methods Pig hair follicles were cultured with Williams E medium (control group) or Williams E medium with water soluble extracts of Chinese herbs (experimental group). Hair growth and morphological changes in the hair follicle bulb were observed by microscope, and apoptosis of the pig hair follicle cells was detected by a TUNEL technique. Results On day 7 of culture, the hair growth in the control group was slower than that in the experimental group (P