Baeyer-Villiger monooxygenases (BVMOs) are important biocatalysts to synthesize a series of valuable esters and lactones. Based on protein sequence alignment and crystal structure analysis, a nonconserved hinge which linked NADPH domain and FAD domain was speculated to play an important role in substrate recognition and catalytic oxidation process. Cyclohexanone monooxygenase (CHMO) was selected as a model. Mutants obtained by homologous replacement of the whole hinge almost completely lost its original catalytic activity, demonstrating that the overall hinge structure was of great importance. Some significant sites were identified to greatly affect the catalytic activity and stereoselectivity by alanine scanning mutagenesis, accompanied by enzyme activity assessments and chiral kinetic resolutions. Altering K153 decreased the activity of the enzyme but enhanced the stereoselectivity. Changing L143 site reduced stereoselectivity but had little effect on enzyme activity. Mutation at L144 site dramatically weakened both activity and stereoselectivity. Subsequently, these corresponding sites in phenylacetone monooxygenase were also illustrated to follow a similar rule, revealing a universal importance of these sites in the BVMO family. These results expanded our understanding of the structure-activity relationship of these enzymes and provided more proofs for future directed evolution of BVMOs.
Amino Acid Sequence ; Catalysis ; Mixed Function Oxygenases ; chemistry ; Models, Molecular ; NADP ; Oxidation-Reduction ; Oxygenases ; chemistry ; Protein Conformation ; Sequence Alignment ; Structure-Activity Relationship ; Substrate Specificity

Objective: To observe the short-term and long-term efficacy of acupuncture and traction plus Ba Duan Jin (Eight-brocade Exercise) in treating discogenic low back pain (DLBP). Methods: Sixty patients were divided into an observation group and a control group using the random number table method, with 30 cases in each group. The control group was intervened by acupuncture and traction, while the observation group was given additional Ba Duan Jin (Eight-brocade Exercise) practice. The intervention lasted for a total of 1 month, with a follow-up study conducted 6 months later. The visual analog scale (VAS) and Oswestry disability index (ODI) scores in the two groups were compared before and after treatment, and the efficacy was compared at the end of the treatment between the two groups; the relapse rate was compared at the 6-month follow-up between the two groups. Results: The pain VAS and ODI scores decreased after treatment in both groups, and the intra-group differences were statistically significant (all P<0.05); the pain VAS and ODI scores in the observation group were lower than those in the control group after treatment with statistical significance (both P<0.05). At the 6-month follow-up, the relapse rate was 10.3％ in the observation group versus 48.0％ in the control group, and the between-group difference was statistically significant (P<0.05). Conclusion: The combination of acupuncture, traction and Ba Duan Jin (Eight-brocade Exercise) is an effective method for DLBP and patients who received this method are less likely to relapse.

Objective: To investigate the impact of venom nerve growth factor (vNGF) administered via lateral ventricle on neural progenitor cell proliferation and migration after cerebral ischemia/reperfusion injury in rats. Methods: Ninety healthy and clean male Wistar rats were randomly allocated into 2-day, 7-day, and 14-day groups. Then they were redivided into 5 subgroups at each time point: vNGF 25 U, vNGF 50 U, vNGF 100 U, control, and sham operation. The rat focal cerebral ischemia/reperfusion injury models of the control group and each vNGF subgroup were established. Corresponding dose of vNGF or isotonic saline was administered via the lateral ventricular cannula in all the subgroups according to the specified time points. Immunohistochemical method was used to detect the numbers of DCX positive neural precursor cells around the ischemic cortex and hippocampus CA3/Dentate gyrus in rats of each group. Results: Circled digit oneAfter administering vNGF via the lateral ventricle at each time point, the Longa's scores of the neurological function in all the vNGF subgroups were lower than those in the control group. There were statistical significances (P<0.01). Circled digit twoThe DCX-positive cells in the peri-ischemic cortex and hippocampus CA3/dentate gyrus showed the same change trend. The numbers of DCX positive cells in the 7-d subgroup was higher than those in the 2- and 14-d subgroups when the vNGF dose was the same. There were statistical significances (P < 0.01). Circled digit threeIn comparison of the subgroups with different vNGF doses at the same time points, the numbers of DCX positive cells in the vNGF 50 U subgroup was higher than those of vNGF 25 U and 100 U subgroups. There were statistical significances (P < 0.01). Circled digit fourThe numbers of DCX positive cells at each time point in the vNGF subgroups were significantly higher than those in the control group. There were statistical significances (P < 0.05). Conclusion: After administering vNGF via the lateral ventricle, it may increase the numbers of DCX positive neural precursor cells in the peri-ischemic cortex and hippocampus CA3/dentate gyrus after cerebral ischemia/reperfusion injury in rats.

Adenocarcinoma, Clear Cell ; pathology ; Adult ; Female ; Humans ; Thyroid Neoplasms ; pathology

BACKGROUND: At present, more and more scholars pay attention to the influence of spine and pelvis sagittal balance on the quality of life of patients. Postoperative changes in spine imaging parameters fol owing corrective osteotomy for lumbar degenerative kyphosis have not been reported. OBJECTIVE: To evaluate postoperative changes in sagittal balance fol owing corrective osteotomy for lumbar degenerative kyphosis. METHODS: We retrospectively analyzed 35 consecutive lumbar degenerative kyphosis patients treated with posterior osteotomy fixation in the First Affiliated Hospital of Xinjiang Medical University from February 2012 to December 2014. Imaging parameters were measured before fixation, immediately after fixation and during final fol ow-up. RESULTS AND CONCLUSION: (1) There were significant differences between preoperative and postoperative parameters except for pelvic incidence angle (P < 0.05). (2) There were significant differences between postoperative and last fol ow-up parameters except for Cobb angle, pelvic incidence angle, thoracic kyphosis angle and the thoracolumbar kyphosis (P < 0.05). (3) Pelvic tilt angle was negatively correlated with lumbar lordosis after fixation (r=-0.610, P < 0.001). Thoracic kyphosis was positively correlated with lumbar lordosis (r=0.598, P < 0.001). (4) Results suggested that lumbar sagittal contour can be significantly improved by corrective osteotomy for lumbar degenerative kyphosis. Simultaneously, reciprocal changes in the adjacent areas such as thoracic spine and pelvis occur to adapt to the new sagittal balance.

BACKGROUND:Cervical single-door laminoplasty for chronic compressive myelopathy has obtained exact effects. To reduce the occurrence of related complications, different doctors have proposed different improvement programs, and have achieved a certain effect, but the effect on postoperative complications is not very wel. OBJECTIVE:To evaluate the effect of modified open-door laminoplasty with steel implantation and preservation of bilateral semispinalis. METHODS: We retrospectively analyzed the data of 30 cases of multilevel cervical spondyiotic myelopathy who underwent modified open-door laminoplasty from October 2013 to March 2014. Internal fixation material was Centerpiece titanium plate fixation system. Visual Analogue Scale score, Japanese Orthopaedic Association score (17-score method), neck disability index, range of motion of cervical vertebra, and cervical curvature were compared before treatment and during folow-up. Axial symptom severity was assessed after treatment. RESULTS AND CONCLUSION:The patients were followed up for 12-24 months. No complications appeared during repair, including postoperative spinal cord injury, cerebrospinal fluid leakage, infection or C5 nerve root palsy. Only one patient suffered from axial pain, but there was no need for oral medication. The improvement rate of Japanese Orthopaedic Association score was (76.96±17.61)%. Neck disability index decreased from 12.29±3.82 preoperatively to 8.24±2.86 in final follow-up. Range of motion of cervical vertebra (47.41±17.33)° in final follow-up, accounting for (93.0±4.2)% of preoperative data. Cervical curvature decreased from (13.47±10.54)° preoperatively to (12.88±8.56)° in final follow-up. These findings confirm that modified open-door laminoplasty with preservation of bilateral semispinalis can reserve cervical rear structure to maximum extent, is conducive to early functional exercise after rehabilitation, and reduces the incidence of axial symptoms and loss of cervical curvature.

BACKGROUND:Numerous studies have demonstrated various therapeutic methods for cerebrospinal fluid leakage after spinal column surgery, including intraoperative and postoperative measures. Few studies addressed the therapeutic methods of cerebrospinal fluid leakage after cervical vertebra surgery using lumbar subarachnoid catheter drainage.
OBJECTIVE:To evaluate the therapeutic efficacy of sustainable drainage and lumbar subarachnoid catheter drainage for cervical postoperative cerebrospinal fluid leakage.
METHODS:923 patients underwent cervical spine surgery in the Department of Spinal Surgery, the First Affiliated Hospital of Xinjiang Medical University, China from June 2009 to October 2012. There were 24 cases of postoperative cerebrospinal fluid leakage with an incidence of cerebrospinal fluid leakage of 2.6%(24/923). The dural laceration that could not be repaired or be found induced cerebrospinal fluid leakage. Of them, 12 cases received lumbar subarachnoid catheter drainage (catheter group), and 12 cases received sustainable drainage (drainage group).
RESULTS AND CONCLUSION:Compared with the drainage group, the duration of cerebrospinal fluid leakage was significantly shorter in the catheter group (P<0.05). In the catheter group, one case affected cerebrospinal fluid infection. In the drainage group, two cases experienced cerebrospinal fluid cyst and one case suffered from cerebrospinal fluid infection. They were cured by symptomatic treatment. A total of 24 cases were fol owed up for 9-12 months. None of them affected cerebrospinal fluid leakage, cerebrospinal fluid infection or cerebrospinal fluid cyst. Results demonstrated that lumbar subarachnoid catheter drainage in the treatment of cervical postoperative cerebrospinal fluid leakage has a good effect.

Bone Diseases ; Diagnosis, Differential ; Femur Head Necrosis ; Humans ; Medicine, Chinese Traditional ; methods ; Osteoporosis

Based on the organization and implementation of the comprehensive reform of countylevel public hospitals in 15 provinces (municipalities)in southern China,the research discussed the progress and problems of such reforr.The progress made and areas of the reform vary among provinces and municipalities.For example,the reform has completely covered all the counties in four provinces such as Zhejiang and Jiangsu province.Medicine markups have been canceled in all the pilot counties by adjusting the service prices to pave the way for hospital compensation.Contemporary hospital management,remuneration system and personnel system reform are also main targets of the reform,while the collaboration between superiors and subordinates,and hospital regulatory system have recently been included.Problems are also found with the current reform:for example,lack of attention for the system reform,no fundamental changes in place in the business orientation of hospitals,as well as problems in collaboration among departments,and hospital debts.