BACKGROUND:For teeth with normal dental crown height,pulp cavity retention crown restoration with different depths of the pulp cavity and different repair materials affects the stress and flexural strength of tooth tissue.For short crown molar defects,the research on pulp cavity repair mainly focuses on clinical observation and in vitro flexural strength experiments. OBJECTIVE:To establish a three-dimensional finite element model for short crown molar restored by the endocrown after root canal treatment to analyze the effects of different pulp cavity retention depths and different repair materials on the distribution and size of dentin equivalent stress. METHODS:Based on establishing the complete model of the short crown mandible first molar,a three-dimensional finite element model was established for repairing the distal adjacent defect of the short crown molar with different pulp cavity retention depths(h=2,3,4 mm)and different repair materials(zirconia,lithium disilicate).Under the oblique loading,the equivalent stress distribution was observed.The peak value of dentin equivalent stress and the mean value of equivalent stress near the bottom of the mesial pulp cavity wall were calculated. RESULTS AND CONCLUSION:(1)Equivalent stress concentration areas:The stress of complete short crown molar and restored models mainly concentrated in the mesial root mesial neck and mesial root lingual neck.The stress concentration area was found in the mesial pulp cavity wall corresponding to the bottom layer of restored models,and the stress concentration was obvious in the 4 mm retention depth group.(2)Under the same repair material,the peak value of dentin equivalent stress was the lowest at 3 mm for all models after repair.The average value of equivalent stress near the bottom of the mesial pulp cavity wall was lowest at 3 mm.(3)Under the same retention depth,there was no significant difference between the two materials in the dentin equivalent stress peak and the mean value near the bottom of the mesial pulp cavity.(4)The results showed that under the conditions of this experiment,the endocrown was used to repair the defect of the short crown molar and the retention depth was 3 mm,which was more beneficial to protect the remaining dental tissue.The selection of zirconia or lithium disilicate as the repair material had little effect on the dentin stress.

Objective:To investigate the current situation of the use of transjugular intrahepatic portosystemic shunt (TIPS) for portal hypertension, which should aid the development of TIPS in China.Methods:The China Portal Hypertension Alliance (CHESS) initiated this study that comprehensively investigated the basic situation of TIPS for portal hypertension in China through network research. The survey included the following: the number of surgical cases, main indications, the development of Early-TIPS, TIPS for portal vein cavernous transformation, collateral circulation embolization, intraoperative portal pressure gradient measurement, commonly used stent types, conventional anticoagulation and time, postoperative follow-up, obstacles, and the application of domestic instruments.Results:According to the survey, a total of 13 527 TIPS operations were carried out in 545 hospitals participating in the survey in 2021, and 94.1% of the hospital had the habit of routine follow-up after TIPS. Most hospitals believed that the main indications of TIPS were the control of acute bleeding (42.6%) and the prevention of rebleeding (40.7%). 48.1% of the teams carried out early or priority TIPS, 53.0% of the teams carried out TIPS for the cavernous transformation of the portal vein, and 81.0% chose routine embolization of collateral circulation during operation. Most of them used coils and biological glue as embolic materials, and 78.5% of the team routinely performed intraoperative portal pressure gradient measurements. In selecting TIPS stents, 57.1% of the hospitals woulel choose Viator-specific stents, 57.2% woulel choose conventional anticoagulation after TIPS, and the duration of anticoagulation was between 3-6 months (55.4%). The limitation of TIPS surgery was mainly due to cost (72.3%) and insufficient understanding of doctors in related departments (77.4%). Most teams accepted the domestic instruments used in TIPS (92.7%).Conclusions:This survey shows that TIPS treatment is an essential part of treating portal hypertension in China. The total number of TIPS cases is far from that of patients with portal hypertension. In the future, it is still necessary to popularize TIPS technology and further standardize surgical indications, routine operations, and instrument application.

Objective:To explore the treatment of thoracoabdominal combined injury in a child with heart rupture caused by sheep horns under limited medical conditions.Methods:To summarize the diagnosis and treatment of a child with thoracoabdominal combined injury and cardiac rupture who were treated with epidural anesthesia and having spontaneous breath, and even more there was no oxygen supply and perioperative monitoring during operation.Results:After the complete of thoracoabdominal exploration, the repair of heart, stomach and diaphragm, postoperative anti-infection, nutritional support and symptomatic treatment, the little patient recovered successfully.Conclusions:Thoracoabdominal injuries combined cardiac rupture requires rapid judgment of the patient’s condition, control of bleeding, discharge cardiac tamponade and cardiac repair as soon as possible. In order to save life, unconventional measures can be used when it is necessary.

Objective To explore the impact of prolonged sitting on lumbar disc degeneration using MRI T1ρ and T2 mapping.Methods A total of 25 taxi drivers(prolonged sitting group)and 24 age-matched non-prolonged sitting volunteers(control group)underwent routine lumbar MRI,T1ρ,and T2 mapping.The differences of T1ρ and T2 values for different Pfirrmann grades of anterior annulus fibrosus(AAF),nucleus pulposus(NP),and posterior annulus fibrosus(PAF)were analyzed using Variance analysis,Spearman correlation test,and receiver operating characteristic(ROC)curve was drawn,with independent t-tests was used for between-group com-parisons.Results Statistically significant differences were observed in T1ρ and T2 values for all Pfirrmann Ⅰ-Ⅱ grades NP and Pfirrmann Ⅱ-Ⅳgrades AAF,NP,and PAF in both groups(P＜0.05).Both T1ρ and T2 values were negatively correlated with Pfirrmann grades.The area under the curve(AUC)of T1ρ values for NP at each Pfirrmann grade were 0.928,0.987,and 0.968,respectively,while the AUC of T2 values for NP were 0.777,0.966,and 0.975,respectively.The T1ρ and T2 values of L4/L5 NP and L5/S1 AAF,NP,and PAF were lower in the prolonged sitting group compared to the control group(P＜0.05).Conclusion T1ρ is superior to T2 mapping in detecting lumbar disc degeneration.Prolonged sitting is more likely to cause degeneration of L4/L5 and L5/S1 inter-vertebral discs.

Sarcopenia is a serious health concern that must be payed attention by aged people.The occurrence of sarcopenia in obese older individuals may be intricately linked to lipotoxic substances such as free fatty acids(FFA),diacylglycerols(DAG),and ceramides,which are toxic to skeletal muscle cells.Lipotoxic substances in-duce inflammatory responses,oxidative stress,endoplasmic reticulum stress,and insulin resistance in skeletal mus-cle cells,disrupting protein metabolism and impairing regeneration and then lead to the onset of sarcopenia.Up to the present,the precise mechanisms by which lipotoxicity in skeletal muscle results in the development of sarcope-nia remain incompletely understood.Further research may highlight the orientation for the prevention and treatment of sarcopenia.

Objective:The investigation and research on the application status of Hepatic Venous Pressure Gradient (HVPG) is very important to understand the real situation and future development of this technology in China.Methods:This study comprehensively investigated the basic situation of HVPG technology in China, including hospital distribution, hospital level, annual number of cases, catheters used, average cost, indications and existing problems.Results:According to the survey, there were 70 hospitals in China carrying out HVPG technology in 2021, distributed in 28 provinces (autonomous regions and municipalities directly under the central Government). A total of 4 398 cases of HVPG were performed in all the surveyed hospitals in 2021, of which 2 291 cases (52.1%) were tested by HVPG alone. The average cost of HVPG detection was (5 617.2±2 079.4) yuan. 96.3% of the teams completed HVPG detection with balloon method, and most of the teams used thrombectomy balloon catheter (80.3%).Conclusion:Through this investigation, the status of domestic clinical application of HVPG has been clarified, and it has been confirmed that many domestic medical institutions have mastered this technology, but it still needs to continue to promote and popularize HVPG technology in the future.

Objective:To evaluate the effect of comprehensive intervention measures on reducing the mortality rate of infants born to human immunodeficiency virus (HIV)-infected pregnant women.Methods:A total of 9 773 infants born to pregnant women with positive HIV antibody and confirmed HIV infection in Sichuan Province from 2005 to 2019 were included. The changes of infant mortality, death composition, time of death, and main causes of death in the whole province and different regions at baseline (2005 to 2016) and after comprehensive intervention measures (from 2017 to 2019) were analyzed. Statistical analysis was conducted by chi-square test and trend chi-square test.Results:After the intervention, the infant mortality rate born to HIV-infected mothers was 49.6‰ (221/4 455), which dropped 40.6% compared to the baseline (83.5‰ (444/5 318)), and that in Liangshan Yi Autonomous Prefecture was 53.3‰ (186/3 491), which dropped 48.3% compared to the baseline (103.1‰ (379/3 676)). Furthermore, the infant mortality rate in Sichuan Province and Liangshan Yi Autonomous Prefecture decreased with time (trend χ2=42.058 and 60.041, respectively, both P<0.01). The proportions of infant death of HIV-infected mothers among the total infant death in Sichuan Province and Liangshan Yi Autonomous Prefecture decreased from 29.3% (130/444) and 25.9% (98/379) to 13.6%(30/221) and 9.7%(18/186), respectively, and the differences were statistically significant ( χ2=19.918 and 20.020, respectively, both P<0.01). The infant death time was mainly delayed from less than one month (31.5%(140/444) and 28.5%(108/379), respectively) to 2-3 months (27.6%(61/221) and 28.5%(53/186), respectively) in Sichuan Province and Liangshan Yi Autonomous Prefecture, and the differences were statistically significant ( χ2=24.642 and 26.009, respectively, both P<0.01). The infant mortality rates due to pneumonia, diarrhea, suspected HIV infection, premature delivery or low birth weight decreased from 44.4‰ (236/5 318), 12.0‰ (64/5 318), 4.9‰ (26/5 318) and 4.3‰ (23/5 318) at baseline to 26.9‰ (120/4 455), 7.6‰ (34/4 455), 1.8‰ (8/4 455) and 0.7‰ (3/4 455), respectively, and the differences were statistically significant ( χ2=21.010, 4.734, 6.691 and 12.182, respectively, all P<0.05). Conclusions:Through the implementation of comprehensive intervention measures, the infant mortality rates of HIV-infected mothers in Sichuan Province and the high endemic areas decrease significantly. However, it is necessary to pay more attention to the high death risk and the infant death in the middle or low endemic areas. The infant health care of HIV-infected mothers within six months should be strengthened. The quality of follow-up and health care services targeted to the main cause of death should be improved.

Objective:To explore the application effect of intelligent network-management system in the management of electronic controlled analgesic pump.Methods:A total of 70 medical staff were selected in Department of Anesthesiology from Peking University People′s Hospital from June to August 2018 and March to June 2019. Self controlled design was adopted. The data of 70 doctors and nurses were collected by comparing the development of electronic controlled analgesia pump before and after the two management modes in analgesia pump management of time-consuming and care satisfaction results.Results:Before the application of intelligent management system in the electronic controlled analgesia pump , the average access time of the analgesia pump was (3.725±0.332) min, and the satisfaction rate was 64.29% (45/70); after the application of the intelligent management system, the average access time of the analgesic pump was (1.901±0.237) min, and the satisfaction rate of the nurses was 97.14% (68/70). The difference before and after the application was statistically significant ( t value was 46.197, χ2 value was 8.425, P<0.05). Conclusions:Application of intelligent management system in the process of electronic controlled analgesia pump can effectively shorten the average access time of the analgesia pump, increase satisfaction rate, improve the work efficiency of clinical medical staff, and realize the network management of anesthesia analgesia pump.

Objective:To explore the influencing factors on perinatal mortality of pregnant women with HIV infection to reduce the mother-to-child transmission in Sichuan province.Methods:In this study, 4 786 perinatal infants of the HIV-infected pregnant women were included. Related data on perinatal epidemiology was reported by all the 183 medical and health care institutions where the HIV prevention of mother-to-child transmission program was initiated in 2005-2016. Univariate χ2 test and multivariate logistic regression methods were used to analyze the perinatal mortality outcomes and influencing factors. Results:The overall perinatal mortality rate was 25.7‰ (123/4 786) among HIV-infected pregnant women, with annual downwarding trend (trend χ2=32.220, P=0.000). Perinatal mortality rate appeared the highest ( χ2=4.130, P=0.042), with more fetal deaths and stillbirths and less early neonatal death within 7 days in Liangshan county ( χ2=29.626, P=0.000). Results from the multivariate logistic regression analysis showed that fewer pregnant numbers would contribute to the, lower perinatal mortality rate (1-2 pregnancies OR=0.417, 95 %CI: 0.184-0.943; 3-4 pregnancies OR=0.447, 95 %CI: 0.223-0.895). Perinatal deaths were more likely to be prevented if LPV/r protease inhibitor-based triple antiviral therapy was provided ( OR=0.530, 95 %CI: 0.285- 0.986) or delivery was taken place in the hospital (hospital of municipal-level and above OR=0.222, 95 %CI:0.098-0.499; county-level hospital OR=0.282, 95 %CI: 0.166-0.480; township-level hospital OR=0.134, 95 %CI: 0.031-0.586) among HIV-infected pregnant women. However, premature delivery or neonatal asphyxia would increase the risk of perinatal mortality (premature delivery OR=8.285, 95 %CI: 5.073-13.533; neonatal asphyxia OR=9.624, 95 %CI: 4.625-20.028). Conclusions:The perinatal mortality rate of HIV-infected pregnant women appeared significantly higher than that in the province or the whole country. Strategies involving LPV/r-based triple antiviral therapy, promotion of hospital delivery, reducing the incidence rates of premature deliveries and neonatal asphyxia, should be strengthened.

To investigate the feasibility and clinical effects of lobulated free latissimus dorsi flap in repairing severe shank trauma with irregular soft tissue defect. Methods Eight patients with soft tissue defect of shank due to trauma were treated from February, 2013 to November, 2018, which were 5 males and 3 females. All wounds were irregular.The size of soft tissue defect ranged from 11.0 cm×15.0 cm to 15.0 cm×23.0 cm, with different degrees exposure of deep tissue such as bone and tendon. Five cases out of 8 were infected wound, 3 cases of which had internal fixation bracket exposed. Five infected wounds were firstly treated with negative pressure after debride-ment, then repaired with flap transplantation until the infection were completely controlled. Other wounds were re-paired directly after debridement. The free lobulated latissimus dorsi flap was designed and applied to repair the ir-regular soft tissue defect of shank.The lobulated latissimus dorsi flap with the outer branch of the thoracodorsal artery ranged from 14.0 cm×7.0 cm to 24.0 cm×8.5 cm.The lobulated latissimus dorsi flap with the inner branch of the tho-racodorsal artery ranged from 10.0 cm×5.0 cm to 15.0 cm×7.0 cm. When cutting the flap, the branch vessels should be protected to insure the continuity of the thoracodorsal artery. After spliced the 2 lobulated flaps, the thoracodorsal arteriovenous was anastomosed with the recipient region arteriovenous. All the donor sites were sutured directly. All patients were followed-up by outpatient and telephone regularly. Results Seven flaps survived well.Only 1 case of partial necrosis appeared at the distal edge of the lobulated flap and healed after wound care. All patients were fol-lowed-up from 3 to 30 months, averaged of 14 months. The texture of flap was flexible and the appearance was well. Only a linear scar was left in the donor site. The shoulder joint retained good mobility. Conclusion The lobulated latissimus dorsi flap has rich blood supply, concealed donor area and high survival rate after transplantation, which can flexibly repair the irregular soft tissue defect of the shank, and effectively prettify the appearance of the recipient area. This strategy has little effect on the appearance and function of the donor area, and worthy of promoting in clinic.