Objective To clone the reconstructed Hc gene of botulinum neurotoxin type A(BoNT/AHc)and to explore the soluble expression of the reconstructed gene in E.coli.Methods The gene of Hc fragment was synthesized by replacing rare codons with frequent ones in E.coli,while the components of amino acids didn't change,and the contents of AT decreased from 76.4 % to 57.3%.The reconstructed gene was then cloned into the prokaryotic expression vector pQE-60.The recombinant plasmid pQE-60Hc was introduced into E.coli Origami(DE3)that was induced to express the protein.The soluble expression products were then detected by Western Blot.Finally the expressed product of recombination plasmid pQE-60Hc was analyzed with SDS-PAGE after purification through Ni-NTA column.Results The reconstructed Hc gene of BoNT/AHc was amplified by PCR.The expression vector pQE-60Hc was constructed successfully with BamH Ⅰ and Nco Ⅰto ingest both BoNT/AHc and vector pQE-60.Reconstructed gene could be expressed effectively in E.coli in soluble form.The molecular weight of expressed product of recombination plasmid pQE-60Hc analyzed by SDS-PAGE was 52 000,which was the same as anticipated.And the soluble expression product accounted for to 11.5 % of the total bacterial protein.Western blot assay showed that the expression product could bind to specific antibody agent BoNT/A.Conclusion The expression vector has been constructed and the reconstructed gene was expressed successfully and effectively in E.coli,which may provide a foundation for further study on antitoxin and vaccine.

In anaerobic bottles fermentation,glucose,fructose,xylose,lactose,maltose,sucrose and sugar alcohols could be used to produce succinic acid with Actinobacillus succinogenes. When sorbitol was utilized as the carbon source in the batch fermentation,more succinate and ethanol were produced compared with those using glucose,while producing less acetate and formate. The metabolic flux analysis results showed that the flux partitioning at PEP node was stable when glucose was replaced by sorbitol,but the flux partitioning at PYR and AcCoA nodes changed a lot because more reducing power(NADH) was generated to meet the more requirement the synthesis of succinate and ethanol.

Objective To observe the clinical therapeutic outcomes and the radiographs changes of lumbar degeneration disease treated by dynamic stabilization device (Wallis). Methods Eighty-four cases of lumbar degeneration disease were treated by threaded fusion cage, from May 1997 to May 2002. The JOA scores, the rate of fusion,cage sink and adjacent segment degeneration were observed. Results The average hospitalizotion was 23.59 days. The mean operation time was 3.00 hours. The mean JOA scores were 13.93 before the operation,while 26.69 on the end of the following time respectively; there was statistical significant. The mean motion of operative segment was 5.22 before operation, while 2.44 on the end of the following time respectively. The mean extension of operative segment was 3.32 before operation ,while 1.39 on the end of the following time respectively. The mean motion of adjacent segment was 3.68 before operation, while 6.54 on the end of the following time respectively. The mean extension of adjacent segment was 1.95 before operation,while 3.95 on the end of the following time respectively. There were all statistical significant on those changes of Cobbs angel. Conclusions The long-term therapeuptic effect of WALLIS treatment for lumbar degeneration disease is reliable. The motion of operative segment was significant decreased, especially on extension. The motion of adjacent segment was significant increased, the degree extension of adjacent segment was also significant increased.

A novel unsaturated polyphosphoester (UPPE) was devised in our previous research, which is a kind of promising scaffold for improving bone regeneration. However, the polymerization process of UPPE scaffolds was unfavorable, which may adversely affect the bioactivity of osteoinductive molecules added if necessary, such as recombinant human bone morphogenetic protein-2 (rhBMP2). The purpose of this study was to build a kind of optimal scaffold named UPPE-PLGA-rhBMP2 (UPB) and to investigate the bioactivity of rhBMP2 in this scaffold. Furthermore, the cytotoxicity and biocompatibility of UPB scaffold was assessed in vitro. A W1/O/W2 method was used to fabricate PLGA-rhBMP2 microspheres, and then the microspheres were added to UPPE for synthesizing UPB scaffold. The morphological characters of PLGA-rhBMP2 microspheres and UPB scaffolds were observed under the scanning electron microscopy and laser scanning confocal microscopy. The cumulative release of UPB scaffolds was detected by using ELISA. The cytotoxicity and biocompatibility of UPB scaffolds were evaluated through examining the adsorption and apoptosis of bone marrow stromal cells (bMSCs) seeded on the surface of UPB scaffolds. The bioactivity of rhBMP2 in UPB scaffolds was assessed through measuring the alkaline phosphates (ALP) activity in bMSCs seeded. The results showed that UPB scaffolds sequentially exhibited burst and sustained release of rhBMP2. The cytotoxicity was greatly reduced when the scaffolds were immersed in buffer solution for 2 h. bMSCs attached and grew on the surface of soaked UPB scaffolds, exerting well biocompatibility. The ALP activity of bMSCs seeded was significantly enhanced, indicating that the bioactivity of rhBMP2 remained and still took effect after the unfavorable polymerization process of scaffolds. It was concluded that UPB scaffolds have low cytotoxicity, good biocompatibility and preserve bioactivity of rhBMP2. UPB scaffolds are promising in improving bone regeneration.

Objective To summarize the diagnosis and treatment of urethral injury in children ,and to discuss the effective treat-ment method .Methods The retrospective analysis was performed on the data of 73 cases of children urethral injury in this hospital during recent 10 years .Results 66 cases were male ,7 cases were female ,aged 1-15 years old(average 7 years old) .In the male ca-ses ,there were 8 cases of anterior urethral injury ,10 cases of bulbous urethral injury ,44 cases of posterior urethral injuries and 4 cases of bladder neck injury ;in the female cases ,there were 6 cases of urethral injury and 1 case of bladder neck injury .The once cure rate of urethral realignment was 78 .6% ,which of stageⅠ urethral anastomosis was 80% and which of stage Ⅱurethral repair was 69 .6% .Conclusion Different operation modes have their advantages and disadvantages .The corresponding treatment scheme should be formulated according to the comprehensive assessment of the patient′s general condition and damage types .

BACKGROUND:The studies have shown that the mesenchymal stem cel s derived from bone marrow and umbilical cord can be continuously cultured in vitro, and maintain the characteristics of stem cel s. The mesenchymal stem cel s can differentiate into hepatocyte-like cel s after“cocktail”induction by various cytokines. OBJECTIVE:To further identify whether umbilical cord-derived mesenchymal stem cel s in vitro co-cultured with normal hepatocytes can differentiate into hepatocyte-like cel s, and to investigate the differentiation method. METHODS:Mesenchymal stem cel s were isolated from human umbilical cord with adherent method, and the surface markers of umbilical cord-derived mesenchymal stem cel s were detected with flow cytometry. The umbilical cord-derived mesenchymal stem cel s were co-cultured with liver LO2 cel s without adding exogenous inducers. The expressions of alpha-fetoprotein, albumin and human cytokeratin 19 mRNA of hepatocyte specific markers were detected with reverse transcription PCR at 7, 14 and 21 days after culture, and periodic acid-Schiff staining was used to identify the functions. RESULTS AND CONCLUSION:Mesenchymal stem cel s could isolated from human umbilical cord successful y, showing fibroblastic morphology and adherent cel characterization. Among these cel s, 96.02%cel s were CD29 positive cel s and 96.6%cel s were CD105 positive cel s. The percentage of CD34 negative cel s was 99.65%. The percentage of CD105+CD29+double positive cel s was 94.84%. The mRNA of alpha-fetoprotein was found on the 7th day after co-cultured with LO2 cel s, and the mRNA of albumin and human cytokeratin 19 were found on the 14th day. After co-cultured for 21 days, the alpha-fetoprotein mRNA could not be observed in the co-culture group. The expressions of albumin and human cytokeratin 19 were increased at 14 days. After co-cultured for 21 days, the glycogen staining was positive. Umbilical cord-derived mesenchymal stem cel s can differentiate into hepatocyte-like cel s after co-cultured with normal hepatocytes.

A novel unsaturated polyphosphoester (UPPE) was devised in our previous research, which is a kind of promising scaffold for improving bone regeneration. However, the polymerization process of UPPE scaffolds was unfavorable, which may adversely affect the bioactivity of osteoinductive molecules added if necessary, such as recombinant human bone morphogenetic protein-2 (rhBMP2). The purpose of this study was to build a kind of optimal scaffold named UPPE-PLGA-rhBMP2 (UPB) and to investigate the bioactivity of rhBMP2 in this scaffold. Furthermore, the cytotoxicity and biocompatibility of UPB scaffold was assessed in vitro. A W1/O/W2 method was used to fabricate PLGA-rhBMP2 microspheres, and then the microspheres were added to UPPE for synthesizing UPB scaffold. The morphological characters of PLGA-rhBMP2 microspheres and UPB scaffolds were observed under the scanning electron microscopy and laser scanning confocal microscopy. The cumulative release of UPB scaffolds was detected by using ELISA. The cytotoxicity and biocompatibility of UPB scaffolds were evaluated through examining the adsorption and apoptosis of bone marrow stromal cells (bMSCs) seeded on the surface of UPB scaffolds. The bioactivity of rhBMP2 in UPB scaffolds was assessed through measuring the alkaline phosphates (ALP) activity in bMSCs seeded. The results showed that UPB scaffolds sequentially exhibited burst and sustained release of rhBMP2. The cytotoxicity was greatly reduced when the scaffolds were immersed in buffer solution for 2 h. bMSCs attached and grew on the surface of soaked UPB scaffolds, exerting well biocompatibility. The ALP activity of bMSCs seeded was significantly enhanced, indicating that the bioactivity of rhBMP2 remained and still took effect after the unfavorable polymerization process of scaffolds. It was concluded that UPB scaffolds have low cytotoxicity, good biocompatibility and preserve bioactivity of rhBMP2. UPB scaffolds are promising in improving bone regeneration.
Bone Morphogenetic Protein 2 ; chemistry ; pharmacology ; Bone Regeneration ; drug effects ; Humans ; Lactic Acid ; chemistry ; pharmacology ; Phosphatidylinositol Phosphates ; chemistry ; pharmacology ; Polyglycolic Acid ; chemistry ; pharmacology ; Tissue Scaffolds

Succinic acid has received a great deal of attention as an important green chemical stock for the manufacture of synthetic resins, biodegradable polymers and chemical intermediates. In this paper, the breeding mechanism of Actinobacillus succinogenes based on metabolic flux analysis was demonstrated to improve the yield of succinic acid by fermentation. After the NTG treatment, mutants from A. succinogenes CGMCC 1593 which were able to grow in medium containing concentrations of about 50-100 mmol/L of sodium monofluoroacetate were obtained. Among them, a mutant SF-9 was selected for producing more succinic acid and less acetic acid. When fermentations were conducted in a 5 L bioreactors, the final succinic acid concentration of SF-9 (34.8 g/L) increased 23.4%, and the mass ratio of succinic acid/acetic acid increased from 3.3 to 9 compared with those of the parent strain. Based on the metabolic flux analysis of A. succinogenes, PEP was found to be a key node which has an important effect on the production of succinic acid, and the flux ratio of by-productions (acetic, formic, lactic acid) was influenced by PYR node. Compared with the parent strain, the flux to succinic acid of mutant (A. succinogenes SF-9) was significantly increased, while the flux to by-productions had an obvious decline. Therefore, PEP and PYR are not rigid nodes in the metabolic regulation of A. succinogenes.
Actinobacillus ; genetics ; growth & development ; metabolism ; Drug Tolerance ; Fermentation ; Fluoroacetates ; metabolism ; Metabolic Networks and Pathways ; Mutation ; Succinic Acid ; metabolism

Objective:To investigate the effect of lateral tibial periosteum distraction on diabetic foot and vasculitis foot.Methods:A retrospective analysis of 13 patients (16 feet) who received lateral tibial periosteal distraction between June 2019 and May 2020 were included in the study. 9 males and 4 females; aged 39-77 years (average 66 years); left foot 7 cases, right foot 9 cases. 5 cases were patients with diabetic foot, 1 case was diabetic foot with arteriosclerosis obliterans, 2 cases were thromboembolic vasculitis, and 5 cases were arteriosclerosis obliterans. The tibial periosteum was dissected and a distraction device was placed. In the 3 patients with foot ulcers, tibial periosteum distraction devices were placed on the severer side. The periosteal distraction began on the third day after surgery, about 0.75 mm/d, the adjustment was done usually in two weeks. Two weeks later, the stretch plate was removed surgically. The followings were evaluated: visual analogue scale (VAS) pain score, foot peripheral oxygen saturation, foot capillary filling test, lower extremity arterial CT angiography (CTA), etc.Results:All 13 patients were followed up for 2-12 weeks, with an average of 3.85 weeks. VAS pain score: the average pain score of 13 patients with preoperative foot pain was 5.31±1.84 (range, 2-9) points, and 2 weeks after surgery, the average value was 2.46±1.39 (range, 1-6) points with statistical significance ( t=6.124, P<0.001) ; peripheral foot oxygen saturation: the average preoperative blood oxygen saturation of 12 patients was 87.83%±14.83% (range, 50%-98%), 1 patient was not detected before surgery, and 2 weeks after operation, the average blood oxygen saturation was 92.33%±7.91% (range, 75%-99%). There was no significant difference between them ( t=1.124, P=0.285). The foot skin temperature of 10 patients was 35.68±0.85 ℃ (range, 34.00-36.60 ℃) before surgery and 36.23±0.46 ℃ (range, 35.50-36.90 ℃) after surgery, and the difference was statistically significant ( t=3.197, P=0.008) . Capillary filling test: 2 weeks after operation, the capillary filling response was significantly improved. All 13 patients had improved CTA of both lower extremity arteries before operation, and 11 patients had CTA taken back after two weeks of operation. Compared with preoperative CTA, new vascular network was found in the operation limb. In addition to 1 patient with thromboangiitis obliterans (mainly suffering from foot pain, no wound symptoms), 2 of 12 patients with heart failure, renal failure and other basic diseases did not heal, and the wounds of the other 10 patients had improved significantly 1 month later. Conclusion:Lateral tibia periosteum distraction can be used to treat chronic ischemic diseases of lower extremities with satisfactory postoperative results.

Objective To summarize the experience of anterolateral percutaneous vertebroplasty (PVP) in the treatment of cervical metastases in advanced lung cancer,and to evaluate its therapeutic effect on patients with cervical metastases in advanced lung cancer.Methods A total of 27 patients with advanced cervical spine metastases were enrolled from July 2009 to September 2018 in Department of Orthopaedics,Beijing Friendship Hospital,Capital Medical University.A retrospective analysis was performed on 20 patients who underwent PVP and had complete follow-up data.There were 12 males and 8 females,aged (59.15±7.55) years.A total of 32 cervical metastases were performed.Bone cement leakage was observed by X-ray and CT after operation,and complications were recorded during and after operation.Follow-up visits were made by outpatient or telephone until the 3rd month after the operation.By comparing visual analogue scale (VAS),analgesic use score,cervical dysfunction index (NDI) and KPS before and after operation,the improvement of the quality of life of patients after operation was comprehensively evaluated.The measurement data were expressed as (Mean ± SD).The paired t test was used to test the normal distribution of the paired difference before and after the operation,and the paired rank sum test was used to test the difference before and after the operation which did not conform to the normal distribution.Results The preoperative Tokuhashi correction score was (7.15 ± 2.87) score in 20 patients and the Tomita score was (7.55 ± 2.21) score.The single-segment cervical vertebrae cement injection volume was (1.17 ± 0.25) ml.The postoperative cement leakage rate was 53.13％ (17/32),but no serious complications.VAS before surgery and 3 months after surgery [preoperative (8.30 ± 1.08) score,postoperative (3.60 ± 1.67) score,P =0.000)],analgesic use score [preoperative (3.35 ± 0.59) score,postoperative (1.70 ± 0.80) score,P =0.000],cervical dysfunction index [preoperative (63.10 ± 7.94) score,postoperative (42.55 ± 15.69) score,P =0.000)] and KPS [Preoperative (54.50 ± 6.86) score,postoperative (61.67 ± 12.95) score,P =0.011] were significantly improved,and the difference was statistically significant.Conclusion PVP via anterolateral approach is effective in the treatment of advanced cervical metastases of lung cancer,and can effectively improve the quality of life of patients with advanced cervical metastases,but the surgical leakage rate is high and needs attention.