Immortalized human precartilaginous stem cells (IPSCs) were established to provide stable cell resource for the study of the molecular mechanism of gene targeting on the differentiation of PSCs. Plasmid pCMVSV40T/PUR containing simian virus 40 large T antigen gene (SV40Tag) was transfected into human PSCs by using lipofectin transfection. Colonies were isolated by puromycin selection and expanded by multiple passages. Immunohistochemistry, RT-PCR and Southern blotting were used to identify the transfected cells and to detect the expression and integration of SV40Tag in expanded cell lines. The positive colonies were isolated and subcultured, designated immortalized precartilaginous stem cells (IPSCs), which were confirmed as fibroblast growth factor receptor-3 (FGFR-3) positive cells by immunohistochemistry and RT-PCR. SV40Tag cDNA was found in cultured IPSCs of passage 8 by Southern blotting, and the expressions of SV40Tag mRNA and protein were confirmed by RT-PCR. These findings suggested that IPSCs strain with SV40Tag was constructed successfully.
Cartilage/*cytology ; Cell Proliferation ; Cell Transformation, Viral ; Cells, Cultured ; Fetus ; Simian virus 40/*genetics ; Stem Cells/*cytology ; Transfection

Objeetive To analyze the effect of treatment of rhegmatogenous retinal detachment(RRD) by scleral bucking as well as the relative risk factors affecting the anatomical reattachment and visual recovery.Methods One hundred and fortyeight patients (148 eyes) with RRD treated by sclera buckling surgery in our hospital during January 2012 to January 2016 were retrospectively analyzed.The rate of postoperative retinal anatomic reattachment,the best corrected visual acuity (BCVA) and complications were observed.Logistic regression analysis was performed to analyze the correlative factors affecting the anatomical reattachment and postoperative vision restoration.R~ults Retinal reattachment achieved in 91.9％ after initial surgery and the final success rate for anatomic reattachment was 97.3％ assessed with ophthalmoscope and fundus photography.But these two rates were assessed with the optical coherence tomography (OCT) were 60.1％ and 80.4％ respectively.Single factor Logistic regression analysis showed that retinal detachment was affected by multiple breaks and Grade C1 PVR(all P ＜0.05);Single factor Logistic regression analysis showed that preoperative BCVA,course of disease,retinal detachment range,macular involvement or not had an impact on the postoperative recovery of BCVA (all P ＜ 0.05),preoperative age,refractive status,releasing retinal fluid or not,intravitreal gas injection,combined scleral buckling,and postoperative subretinal fluid,all of these factors had no effect on BCVA recovery after surgery (all P ＞ 0.05).And through multiple factors Logistic regression analysis,preoperative BCVA was an independent risk factor for BCVA recovery after surgery (P ＜ 0.05).Conclusion Scleral bucking is an effective technique for managing RRD,but multiple breaks and Grade C1 PVR are significant risk factors for anatomic.Preoperative BCVA,course of disease,retinal detachment range,macular involvement or not have the impact on the BCVA recovery after scleral buckling,and the preoperative BCVA is the key factor.Early diagnosis and early treatment as well as protecting the preoperative visual acuity can improve prognosis.

This study was aimed to verify the chemical component cantharidin from Chinese blister beetle by LC-MS/MS. Components were first processed by HPLC to choose the appropriate separation conditions before LC/MS/MS analysis. Through the positive and negative ions pre-scan, positive ions scanning way was selected in the scanning of each separate component. The scanned maps were obtained and the relative molecular mass was deduced. The results showed that 8 types of cantharidin compounds were identified, including three isomers. It was concluded that LC-MS/MS was able to determine the chemical component cantharidin from Chinese blister beetle rapidly and accurately, which was existed in the body by the form of combined amino acid.

Objective To observe the effects of myelotomy on autophagy activation after traumatic spinal cord injury (SCI) in rats. Methods 54 adult female Sprague-Dawley rats were randomly assigned to sham-operated group (SG, n=18), contusion group (CG, n=18) or myelotomy group (MTG, n=18). The T10 SCI model in rats was induced with a New York University (NYU) impactor and myelotomy was performed 24 hours after SCI. They were evaluated with the BBB score 1, 7, 14 days after injury. The expression of mRNA of Beclin-1 and Bcl-2 were detected with real-time quantitative reverse transcriptase polymerase chain reaction (RT-PCR). The formation of autophagosome was investigated under electronic microscope (EM) 3 days after injury. Results BBB score was more in the MTG than in the CG 7 and 14 days after injury (P<0.05), while the expression of Beclin-1 mRNA was less (P<0.05). The expression of Bcl-2 mRNA was more in the MTG than in the CG 3 and 7 days after injury (P<0.05). The expression of Beclin-1 mRNA was negatively correlated with BBB scores (P< 0.05). The formation of autophagosome was less in the MTG than in the CG. Conclusion Myelotomy can improve the recovery of motor function in rats after acute traumatic SCI, which may associate with neuroprotection mediated by inhibition of autophagy through the Bcl-2 signaling pathway.

Objective: To analyze the level and trend of microbial contamination in food in rural compulsory education schools in Baiyin City, so as to provide a reference for playing an early warning role in eliminating potential food safety hazards as soon as possible. Methods: According to the "National Food Contaminants and Harmful Factors Risk Monitoring Workbook", etc., 8 pathogenic bacteria such as Salmonella, Listeria monocytogenes, Staphylococcus aureus, total bacterial count, and 2 hygienic indicator bacteria of coliform were tested. Results: A total of 908 food samples were collected from 2013 to 2021, 47 were positive and the overall positive rate was 5.18%. The positive rate of samples collected in different years showed a downward trend year by year. The detected pathogenic bacteria ranked from high to low as follows: Escherichia coli (1.87%), Bacillus cereus (0.99%), Staphylococcus aureus (0.44%), mold (0.33%), Listeria monocytogenes (0.22%). Hygiene indicator bacteria total number of bacteria exceeded the standard rate was higher (2.09%). Among all kinds of food, milk and dairy products, frozen food, cold food, barbecue, rice and flour products had higher positive rates. According to quarterly statistics, the positive rate in the first and second quarters was relatively high. Conclusion There are different degrees of microbial contamination risks in the food of rural compulsory education schools. All relevant departments should pay attention to the current situation of school food hygiene and safety in poverty stricken areas, and strengthen rural compulsory education school food, especially for milk and dairy products, frozen food, cold food, Supervision of key foods such as barbecue, rice and flour products, and efforts to improve their safety standards, do a good job in school food hygiene and safety, and ensure the healthy growth of young people.

Immortalized human precartilaginous stem cells (IPSCs) were established to provide stable cell resource for the study of the molecular mechanism of gene targeting on the differentiation of PSCs.Plasmid pCMVSV40T/PUR containing simian virus 40 large T antigen gene (SV40Tag) was transfected into human PSCs by using lipofectin transfection.Colonies were isolated by puromycin selection and expanded by multiple passages,lmmunohistochemistry,RT-PCR and Southern blotting were used to identify the transfected cells and to detect the expression and integration of SV40Tag in expanded cell lines.The positive colonies were isolated and subcultured,designated immortalized precartilaginous stem cells (IPSCs),which were confirmed as fibroblast growth factor receptor-3 (FGFR-3) positive cells by immunohistochemistry and RT-PCR.SV40Tag cDNA was found in cultured IPSCs of passage 8 by Southern blotting,and the expressions of SV40Tag mRNA and protein were confirmed by RT-PCR.These findings suggested that IPSCs strain with SV40Tag was constructed successfully.

Objective:To investigate the results of the superficial circumflex iliac artery(SCIA)-based conjoined flap for covering extremely large lower limb defects.Methods:From February 2017 to June 2019, 15 patients were admitted, who suffered from severe degloved injury for the lower limb, including 9 males and 6 females with a median year of 45 (ranged, 36-67 ) years old. All were taken thorough and radical debridement and covered by the VSD device during the emergency operation. The dimension of defects was ranged from 25.0 cm ×8.0 cm to 50.0 cm ×15.0 cm. Using the lower abdominal wall or side chest wall as the donor site, the conjoined flap was dissected when the wound surface became granulating. The perforator match fashions included bilateral SCIA, and ipsilateral SCIA and thoracodorsal artery(TA). The donor sites were primary closure. The follow-up was accomplished by the same surgeon.Results:Fourteen flaps survived completely without significant complications, and distal necrosis was observed in one longitudinal flap, which was healed with the skin graft in the second stage. All flaps were available for a mean follow-up of 18 (ranged 16-24) months. The aesthetic outcomes were achieved on the recipient site without hairy appearance and hyper-pigmentation. A concealed line scare was left on the donor site, without the hernia and limited function. At the last follow-up, 7 cases were excellent and 1 case was good, evaluated with the LEFS criteria. And 6 cases were excellent and 1 case was good, assessed by the AOFAS criteria.Conclusion:The simultaneous reconstruction of extreme lower limb defects and better salvage treatment could be achieved by the SCIA-based conjoined flap. And as a versatile flap, it was blessed with concealed donor site, various design fashions, and larger dissection size in selected cases.

Objective:To investigate the effect of using the free medial planar artery flap(MPAF) pedicled by the superficial branch of the medial plantar artery in repair of pulp defect of thumb and finger.Methods:Ten patients with pulp defect of thumb and finger were repaired with MPAF of foot in the Department of Hand Surgery of the Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University from November 2020 to January 2022. There were 3 cases of cutting injury, 2 cases of chainsaw injury, 2 cases of extrusion injury and 3 cases of avulsion injury. Digits injuried: 4 index fingers, 3 thumbs, 2 middle fingers, and 1 ring finger. After admission, Doppler ultrasound was performed to understand the running course of medial plantar artery. Emergency surgeries were performed to repair the pulp defects of thumb and finger with free MPAF, and donor sites were repaired by skin grafting. The area of soft tissue defects was 2.0 cm×2.5 cm-3.0 cm×4.5 cm, and the size of flap was 2.5 cm×3.0 cm-3.5 cm×5.0 cm after debridement. Postoperative effect was assessed over the follow-up at outpatient clinics by same group of surgeons. Functional recovery was evaluated according to the Evaluation Standard of Upper Limb Partial Functional of Hand Surgery of Chinese Medical Association.Results:All 10 free MPAFs pedicled by the superficial branch of medial plantar artery survived. After the transfer, the colour, texture and thickness of the flaps were matched with the digit with pulps realistic appearance. Secondary flap thinning surgery was not required. Two cases had blisters at the distal end of the flap, and healed after fluid extraction and dressing change. All patients had 3 to 18 months of follow-up. The TPD of the flap was 4-7 mm. The skin grafts in the donor sites survived well. At the last follow-up, the upper limb function was evaluated according to the Evaluation Standard of Upper Limb Partial Functional of Hand Surgery of Chinese Medical Association, with the results of 8 cases in excellent and 2 in good.Conclusion:Free MPAF pedicled by the superficial branch of medial plantar artery can repair the pulp defect of thumb and finger with reliable blood supply, excellent texture and good appearance. And there is no damage to the main vessels in the donor site.

Objective: To evaluate the clinical application of single-arm external stent combined with free flap in the treatment of forearm fractures of Gustilo type Ⅲ. Methods: A retrospective study was conducted of the 16 patients who had been treated at Repair and Reconstruction Center, Traditional Chinese Medicine Hospital Affiliated to Southwest Medical University from September 2015 to January 2018 for open forearm fractures combined with soft tissue defects with single-arm external stent combined with free flap. They were 11 men and 5 women, aged from 18 to 64 years (average, 41.6 years). By the Gustilo classification, 9 cases were type ⅢB and 7 type ⅢC. The area of soft tissue defects at the upper arm and hand ranged from 7.5 cm×5.5 cm to 16.5 cm × 11.0 cm. Emergency debridement was performed at the primary stage. After repair of major blood vessels, nerves and tendons, the reduced fractures were fixated with a single-arm external stent. The soft tissue defects were repaired with free flaps at the secondary stage. Nine cases were repaired with a free anterolateral perforating branch flap and 7 with a free ilioinguinal flap. The single-arm external stent became the ultimate fixation mode in 5 cases but was changed into plate fixation after survival of the flaps in the other 11 cases. Complications were recorded postoperatively. At the last follow-up, the upper limb function was evaluated according to the tentative criteria for evaluation of the upper limb function proposed by the Hand Surgery Society of Chinese Medical Association. Results: Of all the free flaps, 14 survived smoothly but 2 anterolateral ones survived only after the venous crisis appearing at 24 h after operation was relieved by exploration. The 16 patients were followed up for 9 to 18 months (average, 13.5 months). The fractures united well with fine alignment of the fracture ends and recovered force line. According to the Anderson criteria for forearm fractures, 10 cases were excellent, 4 good and 2 fair after operation. According to the tentative criteria for evaluation of the upper limb function proposed by the Hand Surgery Society of Chinese Medical Association, 11 cases were excellent and 5 good. No nail infection or nonunion occurred. Conclusion In the treatment of forearm fractures of Gustilo type Ⅲ, single-arm external stent plus free flap can effectively restore the force line of upper extremity, promote bone healing, allow reasonable timing for wound repair, reduce postoperative complications like infection and osteomyelitis and facilitate functional recovery of the affected extremity.