To cultivate laboratory medicine undergraduates with innovation ability , we estab-lished laboratory medicine undergraduates innovation ability training system by formulating flexible teaching plan, reforming teaching methods, setting up diversified practice base, implementing 'eagles plan' and connecting with international content. Satisfactory effect was achieved after taking this measure.

Objective: To explore the trajectory of the development of permanent caries in 12- to 16-year-old students in Liuyang and to provide a reference for the prevention and management of caries. Methods: Primary and secondary school students who were registered within the Liuyang jurisdiction were screened for caries from September to November by the Liuyang Center for Disease Control and Prevention. A total of 7 297 students between the ages of 12 and 16 years with complete permanent dentition caries monitoring records and traceable deciduous dentition caries monitoring records were selected from 2013 to 2019, and a zero-inflated negative binomial-latent class growth model (ZINB-LCGM) was established to describe the trajectory of the development of individual caries using the decayed missing filled teeth (DMFT) indicators. Results: DMFT of 12- to 16-year-old students in Liuyang were mainly decayed teeth (DT), with the majority occurring in the first permanent molar. According to the ZINB-LCGM model, the students were classified into three latent categories, "slow growth pattern" (28.55%), "rapid growth pattern" (6.59%), and "stable pattern" (64.86%), which followed different nonlinear caries growth trajectories. Females with deciduous teeth caries were more likely to have trajectories showing a “rapid growth pattern” and a “slow growth pattern”. There were significant differences in the trajectories between men and women, as well as between those with and without primary dentition caries. Conclusion The trajectory of the development of caries in 12-16-year-old students shows heterogeneity in terms of different developmental patterns of latent categories, suggesting that females with deciduous dental caries should receive more attention.

Background Small incision lenticule extraction (SMILE) is increasingly applied in the correction of myopia and astigmatism.However,the early clinical outcomes of SMILE for different refractive myopia and astigmatism is seldom reported.Objective This study was to investigate the safety,efficacy,predictability and early stability after SMILE in low,moderate and high myopia.Methods A series of cases-observational study was carried out.A total of 195 eyes of 108 myopic patients were enrolled in Tianjin Eye Hospital from May to December 2012 under the informed consent.The patients were divided into the low (≤-3.00 D),moderate (＞-3.00 to-6.00 D) and high myopia (＞-6.00 D) groups according to different diopters,with 57 eyes,76 eyes and 62 eyes,respectively.SMILE was performed on all the eyes.The uncorrected visual acuity (UCVA)(LogMAR),best corrected visual acuity (BCVA) (LogMAR),equivalent sphere (SE),intraocular pressure,anterior segment and corneal topography were examined before operation and 1 day,1 week,1 month and 3 months after operation to evaluate the effective index (postoperative UCVA/preoperative BCVA),safety index (postoperative BCVA/preoperative BCVA),predictability and early stability of SMILE.The linear regression analysis was used to analyze the relationships between the attempted refraction and the achieved refraction postoperative 3 months in three groups.Results The percentage of UCVA (LogMAR)＜0.1 was 100％,97.1％ and 92.8％ in the low,moderate and high myopia group,respectively in 3 months after SMILE.The postoperative BCVA of all the operated eyes reached preoperative one.The residual SE was (-0.07±0.16),(-0.05 ±0.20) and (-0.08±0.27)D in the low,moderate and high myopia group,respectively in 3 months after SMILE.The percentage of residual SE±0.5 D was 100％,98.7％ and 93.6％ in the low,moderate and high group,and that of SE±1.0 D was 100％ in all of the groups.The postoperative corrected SE was gradually increased with the raise of predicted SE in the low,moderate and high myopia groups (r=0.942,0.959,0.957,all at P＜0.001).Conclusions SMILE is safe,effective,predictable and stable for the correction of low,moderate and high myopia.The corneal wound healing was slightly slower in the low myopia group than that in the moderate and high group.A slight regression of myopic power appears in high myopia eyes 3 months after SMILE.

Background The relationship between corneal central thickness (CCT) and corneal biomechanical property does not reflect the effective amount of ablated tissue because CCT measures only the change in a single point.Corneal volume (CV) is a representative parameter of corneal morphology,and it can fully reflect corneal thickness and tissue distribution.Objective This study was to investigate the correlation between volumetric corneal changes and corneal biomechanical properties after small incision lenticule extraction (SMILE).Methods A prospective series cases-observational study was carried out.This study protocol was approved by Ethic Committee of Tianjin Eye Hospital,and written informed consent was obtained from each patient prior to entering the cohort.Sixty-seven right eyes of 67 myopia or myopic astigmatism patients who received SMILE in Tianjin Eye Hospital from June 2014 to July 2015 were included in this study.Before and 3 months after surgery,the CV at 3,3-5,5-7 and 7-10 mm (CV3,CV3-5,CV5-7,CV7-10) was measured by Pentacam anterior segment analysis system,and corneal hysteresis (CH) and corneal resistance factor (CRF) were obtained by ocular response analyzer (ORA).The changes of CV (ACV),CH (ACH) and CRF (ACRF) were calculated,and the correlations between ACV and ACH or ACRF were analyzed.Results CV3,CV3-5 and CV5-7 values after SMILE were significantly lower than those before SMILE (t =36.24,20.38,16.17,all at P＜ 0.001).The CH values before and after SMILE were (10.06± 1.11) mmHg and (8.10± 1.05) mmHg (1 mmHg =0.133 kPa),and the CRF values before and after SMILE were (10.40 ± 1.38) mmHg and (6.91 ± 1.19) mmHg,respectively,showing significant reduces after SMILE than before SMILE (t =16.71,27.41,both at P＜0.001).Positive correlations were seen between the CV values at different corneal areas and CH value or CRF value.Moderate positive correlations were found between CV3 and CH or CRF (r =0.571,0.569;both at P＜0.001) before surgery,and 3 months after surgery,a weak positive correlation was seen between ACV3 and ACH (r =0.394,P ＜ 0.001) or a moderate positive correlation between ACV3 and ACRF (r=0.501,P＜0.001).Conclusions The CV value is gradually increased from the central cornea to periphery cornea.The CV change is associated with CH and CRF changes after SMILE,and CV3 probably is a useful parameter for the evaluation of corneal biomechanics after refractive surgery.

Objective To investigate the effect of growth hormone replacement therapy on life quality of patients with growth hormone deficiency after sellar tumor surgery.Methods The data of 13 patients undergoing sellar tumor resection and suffering postoperative hypopituitarism from Jun.2009 to Dec.2010.were collected.Each of them was given daily 0.5 units growth hormone (about 0.17 mg) as replacement therapy.The life quality of patients at different time points was evaluated with QoL-GDHA scale.SPSS 17.0 software was used for statistical analysis.Results 1,3,and 6 months after treatment,QoL-GDHA score of the patients was 3.91± 2.29,3.38 + 2.43,and 3.23 + 2.28 repectively,significantly lower than before ( 8.69 ± 2.66).The difference had statistical significance (P ＜0.05 ).Conclusion Growth hormone replacement therapy can significantly improve the life quality of patients with hypopituitarism after sellar tumor surgery.

Objective:To establish a scoring scale for trial of labor after cesarean section (TOLAC), to explore the evaluation ability of this scoring scale for vaginal delivery after cesarean section (VBAC), and to improve the success rate of TOLAC.Methods:The delivery information of 661 TOLAC pregnant women admitted to Zhengzhou Central Hospital Affiliated to Zhengzhou University from 2014 to 2017 was retrospectively analyzed, and the TOLAC scoring scale was established by referring to relevant literatures. A prospective cohort study of pregnant women with TOLAC from January 2018 to December 2019 in Zhengzhou Central Hospital was conducted, including 440 pregnant women who were excluded from contraindications in trial labor. According to TOLAC scoring scale, pregnant women were divided into 3 groups, 0-6 group (94 cases), 7-9 group (234 cases) and 10-15 group (112 cases). The success rate of trial labor, failure reasons and incidence of maternal and neonatal complications were compared among the three groups.Results:(1) The overall success rate of TOLAC in 440 pregnant women was 75.0% (330/440). The success rates of 0-6, 7-9 and 10-15 groups were 53.2% (50/94), 76.9% (180/234) and 89.3% (100/112), respectively. The success rate of 10-15 group were significantly higher than those of 0-6 and 7-9 groups (all P<0.05). (2) Among the causes of trial labor failure, there were statistically significant differences between the three groups in terms of threatened uterine rupture and maternal abandonment (all P<0.05). Pairings showed that the incidences of threatened uterine rupture and maternal abandonment in 0-6 group was lower than those in 7-9 and 10-15 groups, and the differences were statistically significant (all P<0.05). (3) Maternal and neonatal complications mainly included postpartum hemorrhage and neonatal asphyxia, but there were no significant difference in the incidence of TOLAC success or failure among the three groups (all P>0.05). There was no uterine rupture in all groups. (4) The main factors affecting TOLAC score of pregnant women in the three groups included natural labor, estimated weight of the fetus at this time, Bishop score of the cervix at admission and gestational age, and the scores of the above indexes in 10-15 group were significantly higher than those in 0-6 group and 7-9 group (all P<0.05). Conclusions:TOLAC scoring scale has more accurate evaluation ability for VBAC, which could improve the success rate of TOLAC and maternal and child safety. The score of 0-6 is not recommended for vaginal trial labor, the score of 7-9 is recommended for vaginal trial labor, and the score of 10-15 is strongly recommended for vaginal trial labor.

Mixed reality, as a new virtual simulation technology, has been initially applied in the field of surgery. In hepatectomy for primary liver cancer, mixed reality technology has its unique advantages in formulating and evaluating surgical plans before surgery, precise real-time navigation during surgery, and virtual liver teaching, making liver resections more accurate and personalized. This article summarizes the relevant literature at home and abroad in recent years, summarizes the research progress of mixed reality technology in assisted liver resection for primary liver cancer, and discusses its application potential and limitations.

Objective:To explore the advantage of thyroid biopsy and evaluate detection in the application of thyroid cancer cervical lymph node dissection operation guidance, and provide evidence-based basis for guiding PTC patients whether to receive lateral dissection.Methods:The data of 258 patients with thyroid papillary carcinoma admitted to Department of Thyroid Surgery, Affiliated Hospital of Chengde Medical College from April 2018 to December 2019 were retrospectively analyzed. All patients were admitted to the hospital for ultrasonic examination of cervical lymph nodes. According to the examination results, thyroid biopsy and puncture eluent were performed for patients with suspicious signs of metastasis. Patients with positive test results and with metastatic signs in initial ultrasonic examination received lymph node dissection in the cervical region. All patients underwent pathological examination postoperatively to diagnose the lymph node metastasis, and to evaluate the sensitivity, specificity and accuracy of the detection of the patients with lateral clearance.The measurement data was expressed as mean±standard deviation ( Mean± SD), and the count data was expressed as n(%). The software of SPSS21.0 was used to conduct statistical analysis. Results:All 258 patients were successfully completed the diagnosis of various diagnostic methods. Combined with the postoperative pathological diagnosis results, the accuracy rate of ultrasonic diagnosis of lymph node metastasis was 74.42%, the accuracy rate of FNAC diagnosis was 82.95%, the accuracy rate of FNAC-Tg diagnosis was 87.98%, and the accuracy rate of FNAC-Tg diagnosis was 94.96%. The diagnostic sensitivity of ultrasound, FNAC, FNAC-Tg and FNAC-Tg was 73.60%, 81.72%, 91.01% and 95.83%, respectively, and the diagnostic specificity was 76.25%, 86.11%, 79.71% and 88.41%, respectively. In every four months for a time span since April 2018, the average length of hospital stay for patients with each span was (9.17±1.30), (8.39±1.21), (7.94±1.03), (7.46±0.94), (7.33±0.82) d, their neck area incidence of lymph node metastasis were 17.6%, 21.3%, 15.7%, 12.9%, 11.8%, side clear surgical patients accounted for 42.3%, 37.5%, 30.9%, 26.6%, 19.4%. The incidence of lymph node metastasis was 86.8%, 79.4%, 84.5%, 93.2% and 98.1%, respectively.Conclusion:FNAC-Tg method is used in the diagnosis of thyroid papillary carcinoma patients with high sensitivity and specificity of lymph node metastasis, which has certain value in guiding patients whether to perform lymph node dissection.

Liver regenerative medicine can use functional liver cells to repair or replace damaged liver tissue and it is expected to be rapidly developed as an alternative treatment to liver transplantation. However, regenerative medicine requires cells with stable proliferation ability and liver cell characteristics. Liver organoids are derived from adult stem cells or pluripotent stem cells. They can be proliferated in large quantities and cultured for a long time in vitro, meanwhile maintain genetic stability, and simulate the structural and functional characteristics of organs in the body, providing a new strategy for liver regeneration. This article reviews liver organoids and their research progress in liver regenerative medicine, and discusses their application potential and existing limitations.

Objective:To investigate the effects of exogenous hydrogen sulfide on myocardial fibrosis and apoptosis in rats after myocardial infarction and the underlying mechanisms.Methods:Forty-three Sprague Dawley(SD)rats were divided into 4 groups according to the random number table method: a control group(n=12), a myocardial infarction group(MI group, n=13), an hydrogen sulfide(H 2S)group(n=6)and an MI+ H 2S group(n=12). The rat model of acute myocardial infarction was established by intraperitoneal injections of isoproterenol(50 mg/kg, once a day, for 2 days). Electrocardiogram and troponin changes were recorded 48 h after the last drug administration to determine whether the rat model was successfully constructed.After successful establishment of the model, rats in the MI group and the MI+ H 2S group were intraperitoneally injected with sodium hydrosulfide(56 μmol/kg, once a day, for 6 weeks).6 weeks later, echocardiogram and Masson's trichrome staining were performed to assess changes in cardiac function and collagen volume fraction in each group.Terminal deoxynucleotidyl transferase(TdT)dUTP nick end labeling(TUNEL)was used to detect the myocardial apoptosis rate in each group, and Western-blot was used to detect protein expression of Yes-related protein 1(YAP1), WW domain containing transcriptional regulator1(TAZ), mammalian Ste20-like kinase 2(MST2), Bcl-2-associated X protein(Bax), cysteine protease 3(caspase-3), the ratio of matrix metalloproteinase 3(MMP3)/matrix metalloproteinase inhibitor 2(TIMP2), and B-cell lymphoma factor(Bcl-2). Results:Compared with the control group, myocardial collagen volume fraction was increased( P<0.05), the myocardial cell apoptosis rate was increased( P<0.05), and myocardial YAP1, TAZ, MST2, Bax, caspase-3 protein expression and MMP3/TIMP2 ratio were increased in the MI group(all P<0.05), while the expression of Bcl-2 protein was decreased( P<0.05). Compared with the MI group, collagen volume fraction and the cardiomyocyte apoptosis rate were significantly decreased in the MI+ H 2S group( P<0.05). Also, protein expression of YAP1(2.406±0.024 vs.2.830±0.063), TAZ(0.964±0.090 vs.1.329±0.018), MST2(0.780±0.082 vs.1.788±0.097), Bax(1.500±0.008 vs.0.613±0.003)and caspase-3(0.620±0.024 vs.0.780±0.012)and the MMP3/TIMP2 ratio were decreased(all P<0.05), while protein expression of Bcl-2 was increased( P<0.05)in myocardial tissue. Conclusions:H 2S can mitigate myocardial fibrosis after myocardial infarction, through inhibiting the activation of the YAP1/TAZ signaling pathway, thus reducing apoptosis of cardiomyocytes.