Objective To investigate the expression of MutS homolog 3(MSH3)in oral squamous cell carcinoma and its significance.Methods The MSH3 protein expression was examined by immunohistochemistry in 20 normal oral mucosa and 60 oral squamous cell carcinoma tissues.Results Our results showed that MSH3 expression in oral squamous cell carcinoma tissues was lower than normal oral mucosa.The MSH3 expression in oral squamous cell carcinoma tissues with better differentiation was higher than that with worse differentiation.The positive MSH3 expression decreased from oral squamous cell carcinoma patients without lymph nodal metastasis to that with metastasis.MSH3 expression was not related to the patients'gender,age,tumour location or size.Conclusion Downregulation of MSH3 is consistent with poorly differentiation and nodal metastasis in oral squamous cell carcinoma.MSH3 may play a significant role in the malignant progression of oral squamous cell carcinoma.

OBJECTIVE To explore the protective effect of 2,3,5,4’-tetrahydroxy stilbene-2-Ο-β-D-glucosid(TSG) on hearing injury in acetaminophen(APAP) induced guinea pigs. METHODS The ear injury of guinea pigs was induced by APAP, after treatment with TSG, the auditory brainstem response(ABR) and distortion product otoacoustic emission(DPOAE) of guinea pigs were tested to judge the hearing loss, the injury of cochlear hair cells was observed by immunofluorescence, and the liver and kidney tissues of guinea pigs were observed by pathology to judge the toxicity of TSG to liver and kidney. The damage of HEI-OC1 auditory nerve cells induced by APAP was used as the study of ear injury cells. The cell survival and apoptosis were detected by MTT method, cell morphology observation, and flow cytometry, the expression of Birc5 gene was detected by fluorescence quantitative PCR. RESULTS Compared with the model group, on the 14th day, the ABR hearing threshold of guinea pigs decreased significantly, the difference was more significant when the DPOAE test frequency was 2 kHz(P<0.01). The acoustic startle reflex test showed that the amplitude of startle reflex decreased significantly at 100 dB(P<0.05). The gap-prepulse inhibition experiment showed that the amplitude of startle reflex decreased at 10, 40, 50 ms. The guinea pig cochlea was peeled off and the integrity of hair cells was observed after immunofluorescence staining. Compared with the model group, the outer hair cells in TSG group were arranged orderly without loss, and the inner hair cells were basically arranged orderly. Pathological observation showed that TSG had certain hepatotoxicity, but the nephrotoxicity was not obvious. The cell experiment found that the half inhibitory concentration of APAP on HEI-OC1 auditory nerve cells was 800 µmol·L-1. When 10 µmol·L-1 TSG intervened in APAP induced cell injury, the apoptosis rate decreased to 16.0%, which was significantly lower than 25.5% in model(APAP) group. In APAP group, the expression level of Birc5 in HEI-OC1 cells decreased significantly, and TSG treatment could significantly increase the expression level of Birc5. CONCLUSION TSG 15 mg·kg-1 can protect guinea pigs from hearing loss induce by 100 mg·kg-1APAP for 14 d. The protective effect is related to TSG inhibiting APAP induces auditory nerve cell apoptosis and promoting the expression of apoptosis inhibitor Birc5.

Objective To analyze the characteristics of the muscle strength around the knee joint of chondromalacia patellae patients, and to explore the difference with normal people.Methods In March, 2021, 70 knee-onset chondromalacia patellae patients (experimental group) and 35 normal people (control group) were measured isokinetic muscle strength of flexion and extension of knee in angular velocities of 60°/s and 180°/s.Results At 60°/s and 180°/s, the peak torque, the peak torque-to-weight ratio and the total work of the flexor and extensor muscles on the affected side in the experimental group were lower than that of the control group (U > 1097.0, P<0.001). The peak torque, the peak torque-to-weight ratio and the total work of the flexor and extensor muscles at 60°/s and extensor muscles at 180°/s were lower on the affected side than on the healthy side in the experimental group (|Z| > 2.121, P<0.05). The peak torque ratios at 60°/s and 180°/s were more in the affected knees than in the healthy knees of experimental group and in the control group (U > 1810.0, |Z| >3.691, P<0.01).Conclusion The explosive force and endurance of the knee flexor and extensor has weakened in patients with chondromalacia patellae, and there is imbalance in knee joint muscle strength.