Advances in surgical strategies for ossification of posterior longitudinal ligament involving the C 2 segment / 中国修复重建外科杂志

OBJECTIVE@#To evaluate the application of surgical strategies for the treatment of cervical ossification of the posterior longitudinal ligament (OPLL) involving the C 2 segment.@*METHODS@#The literature about the surgery for cervical OPLL involving C 2 segment was reviewed, and the indications, advantages, and disadvantages of surgery were summarized.@*RESULTS@#For cervical OPLL involving the C 2 segments, laminectomy is suitable for patients with OPLL involving multiple segments, often combined with screw fixation, and has the advantages of adequate decompression and restoration of cervical curvature, with the disadvantages of loss of cervical fixed segmental mobility. Canal-expansive laminoplasty is suitable for patients with positive K-line and has the advantages of simple operation and preservation of cervical segmental mobility, and the disadvantages include progression of ossification, axial symptoms, and fracture of the portal axis. Dome-like laminoplasty is suitable for patients without kyphosis/cervical instability and with negative R-line, and can reduce the occurrence of axial symptoms, with the disadvantage of limited decompression. The Shelter technique is suitable for patients with single/double segments and canal encroachment >50% and allows for direct decompression, but is technically demanding and involves risk of dural tear and nerve injury. Double-dome laminoplasty is suitable for patients without kyphosis/cervical instability. Its advantages are the reduction of damage to the cervical semispinal muscles and attachment points and maintenance of cervical curvature, but there is progress in postoperative ossification.@*CONCLUSION@#OPLL involving the C 2 segment is a complex subtype of cervical OPLL, which is mainly treated through posterior surgery. However, the degree of spinal cord floatation is limited, and with the progress of ossification, the long-term effectiveness is poor. More research is needed to address the etiology of OPLL and to establish a systematic treatment strategy for cervical OPLL involving the C 2 segment.

Progress in brewer's yeast cell wall stress response / 生物工程学报

Yeast cell wall plays an important role in the establishment and maintenance of cell morphology upon the cell wall stress. The cell wall of yeast consists of β-glucans, mannoproteins and chitin. The composition and structure remodel due to cell wall stress. Brewer's yeast cell wall exhibits stress response during long-term acclimation in order to adapt to environmental changes. This paper reviews the composition and structure of yeast cell wall and the molecular mechanisms of cell wall remodeling and signal pathway regulation.

Research progresses in microbial 1,3-1,4-β-glucanase: protein engineering and industrial applications / 生物工程学报

1,3-1,4-β-glucanase (E.C.3.2.1.73) is an important industrial enzyme which cleave β-glucans into oligosaccharides through strictly cutting the β-1,4 glycosidic bonds in 3-O-substituted glucopyranose units. Microbial 1,3-1,4-β-glucanase belongs to retaining glycosyl hydrolases of family 16 with a jellyroll β-sandwich fold structure. The present paper reviews the industrial application and protein engineering of microbial β-glucanases in the last decades and forecasts the research prospects of microbial β-glucanases.

Physiological changes of Saccharomyces cerevisiae during serial re-pitching: a review / 生物工程学报

The morphological structure and physiological indexes of Saccharomyces cerevisiae have changed during serial re-pitching due to the stress conditions in serial handlings and the cells become aging. It is of great significance to study the physiological changes of S. cerevisiae during serial re-pitching to understand the anti-aging effect of S. cerevisiae. In this paper, the changes of the physiological indexes during re-pitching of yeast are summarized, and based on the analysis of the previous works further research directions are proposed.

Therapeutic Effect of Posterior Decompression, Internal Fixation and Interlaminar Fusion for Severe Osteoporotic Vertebral Fractures and Collapse Complicated with Spinal Canal Encroachment / 广州中医药大学学报

Objective To evaluate the clinical effect of posterior decompression, internal fixation and interlaminar fusion for the treatment of severe osteoporotic vertebral fracture and collapse complicated with spinal canal encroachment. Methods A retrospective study was carried out in 27 cases of severe osteoporotic vertebral fractures complicated with spinal canal encroachment. The patients were treated with posterior decompression, internal fixation and interlaminar fusion during the period from January 1, 2009 to December 31, 2014. All patients were given vertebral pedicle screw fixation after pedicle augmentation with bone cement. The pain scores of visual analogue scale(VAS), Oswestry Disability Index(ODI), Cobb angle , thoracolumbar Cobb angle and the recovery of neurological function(estimated by Frankel grading system) of the patients were compared beforeoperation, one week after operation and at the end of follow-up. The incidences of internal fixation failure, adjacent vertebral fracture and bone cement leakage also were recorded. Results The patients were followed up for an average of 27 months. The spinal canal occupation rate caused by fracture fragment of posterior vertebral wall was 27.41%~63.85%, with an average of(43.24 ± 10.61)%. Postoperative VAS pain scores, ODI, Cobb angle and thoracolumbar Cobb angle were statistically different from those before operation (P 0.05). In respect of Frankel grading of neurological function at the end of the follow-up, 6 cases were in grade D and 19 cases were in grade E, but the differences were insignificant compared with those before operation (P > 0.05). None of the patients had surgical site infection, screw looseness or breakage, or rod breakage during the follow-up period. There were 8 patients with asymptomatic bone cement leakage after operation. Vertebral compression fractures recurred in 5 patients, of which 2 had adjacent vertebral fractures and 3 had non -adjacent segment. Conclusion The therapy of posterior decompression, internal fixation and interlaminar fusion is effective for the treatment of severe osteoporotic vertebral fracture and collapse complicated with spinal canal encroachment by obviously relieving pain, improving the physiological function of the spine and stabilizing the spine.

Advances in anti-staling brewer's yeast / 生物工程学报

Brewer's yeast is crucial in beer fermentation, mainly beer flavor diversity and stability. Beer flavor stability is one of the most influential beer quality aspects, and screening or breeding brewer's yeast with enhanced anti-staling capacity will be an effective solution. In recent decades, with the progress of genetic engineering and detailed description of brewer's yeast genome, great efforts have been made to improve brewer's yeast. This review highlights recent advances in classical and genetic engineering improvement of yeasts to produce more antioxidant compounds or less beer aging substances and precursors. Therein, improvement targets, evaluation methods and development strategies of anti-staling brewer's yeast are also discussed. Furthermore, hotspot and future trend of anti-staling yeast strain development are also proposed.

Analysis of anti-ulcerative drug use in patients undergoing thyroid operation dur-ing perioperative period / 药学实践杂志

Objective To investigate anti-ulcerative drug (AUD) utility in patients undergoing thyroid operation against stress ulcer (SU ) during perioperative period .Methods A total of 393 patients undergoing arthroscopic operation during Jan . to Dec .2013 in our hospital were recruited and retrospectively analyzed with Excel spreadsheet .Results Among 393 patients in the study ,eighty-five patients (21 .6% ) used AUD (92 .9% )after operation ,most (94 .9% ) were administered by intrave-nous ,and drug utilization index (DUI) was 1 .48 .Eighty-seven point one patients used proton pump inhibitors (PPIs) in which lansoprazole was prescribed most .Conclusion PPIs were overused in patients undergoing thyroid operation .

Improvement of thermostability of beta-1,3-1,4-glucanase from Bacillus amyloliquefaciens BS5582 through in vitro evolution / 生物工程学报

In vitro evolution methods are often used to modify protein with improved characteristics. We developed a directed evolution protocol to enhance the thermostability of the beta-1,3-1,4-glucanase. The thermostability of the enzyme was significantly improved after two rounds of directed evolution. Three variants with higher thermostability were obtained. The mutant enzymes were further analyzed by their melting temperature, halftime and kinetic parameters. Comparing to intact enzyme, the T50 of mutant enzymes 2-JF-01, 2-JF-02 and 2-JF-03 were increased by 2.2 degrees C, 5.5 degrees C and 3.5 degrees C, respectively, the halftime (t1/2, 60 degrees C) of mutant enzymes 2-JF-01, 2-JF-02 and 2-JF-03 were shortened by 4,13 and 17 min, respectively, the V(max) of mutant enzymes were decreased by 8.3%, 2.6% and 10.6%, respectively, while K(m) of mutant enzymes were nearly unchanged. Sequence analysis revealed seven single amino acid mutant happened among three mutant enzymes, such as 2-JF-01 (N36S, G213R), 2-JF-02 (C86R, S115I, N150G) and 2-JF-03 (E156V, K105R). Homology-modeling showed that five of seven substituted amino acids were located on the surface of or in hole of protein. 42.8% of substituted amino acids were arginine, which indicated that arginine may play a role in the improvement of the thermostability of the beta-1,3-1,4-glucanase.This study provide some intresting results of the structural basis of the thermostability of beta-1,3-1,4-glucanase,and provide some new point of view in modifying enzyme for future industrial use.

Optimization of cloning and expression of beta-glucanase gene from Bacillus amyloliquefaciens / 生物工程学报

To compare of performance of beta-1,3-1,4-glucanase gene (bgl) in different expression systems, the beta-1,3-1,4-glucanase gene (GenBank Accession No. EU623974) was amplified from Bacillus amyloliquefaciens BS5582 by PCR and was cloned into three vectors pEGX-4T-1, pET20b(+) and pET28a(+) to construct pEGX-4T-1-bgl, pET20b(+)-bgl and pET28a(+)-bgl recombinant plasmids. The pEGX-4T-1-bgl was transformed into three different Escherichia coli host strains. The pET20b (+)-bgl and pET28a (+)-bgl were transformed into E. coli BL21 (DE3) respectively. Recombinant beta-glucanase was expressed by IPTG inducement in these recombinants. E. coli BL21 (DE3)-pET28a (+)-bgl had the highest enzyme activity. In Luria-Bertani medium, the total enzyme activity was (322.0 +/- 8.8) U/mL, which was 40.1% of original strain in optimal shaking flask condition. This recombinant's performance was studied in Terrific Broth medium under inducement of IPTG and lactose at the same time., and the highest total enzyme activity could reach (1883.3 +/- 45.8) U/mL (818.8% of the original), which indicate that the recombinant strain has a good value in industry application.