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Niu K, Wu XP, Fu Q, Lang KP, Zou SP, Hu ZC, Liu ZQ, Zheng YG. Effects of lipids and surfactants on the fermentation production of echinocandin B by Aspergillus nidulans. J Appl Microbiol 2021; 131:2849-2860. [PMID: 33987908 DOI: 10.1111/jam.15136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 04/03/2021] [Accepted: 04/28/2021] [Indexed: 11/30/2022]
Abstract
AIMS Echinocandin B (ECB) is a kind of lipopeptide antifungal antibiotic, as well as the key precursor of antifungal drug Anidulafungin. Its efficient bioproduction plays an important role in promoting the industrial production of Anidulafungin. METHODS AND RESULTS In this study, methyl oleate and Tween 80 were firstly used to enhance the ECB fermentation by Aspergillus nidulans, the results showed that the ECB titre was significantly enhanced with the addition of methyl oleate and Tween 80. Among the lipids, methyl oleate was found to play a pivotal role in increasing the ECB titre to 2123 mg l-1 , which was more than five times higher than that of the control. The addition of Tween 80 in the medium resulted in ECB titre increased to 2584 mg l-1 . The scanning electron microscope (SEM) and N-phenyl-1-naphthylamine (NPN) assay indicated that Tween 80 could influence the cell membrane permeability of A. nidulans, and enhance the intracellular and extracellular substance exchange, therefore lead to the increasing of ECB titre. CONCLUSIONS Methyl oleate and Tween 80 are optimal carbon sources and surfactants for efficient ECB biosynthesis respectively. SIGNIFICANCE AND IMPACT OF THE STUDY Surfactant was used in ECB fermentation for the first time, which provided feasible ideas for optimizing the fermentation process of other fungi.
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Affiliation(s)
- K Niu
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, P. R. China
| | - X P Wu
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, P. R. China
| | - Q Fu
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, P. R. China
| | - K P Lang
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, P. R. China
| | - S P Zou
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, P. R. China
| | - Z C Hu
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, P. R. China
| | - Z Q Liu
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, P. R. China
| | - Y G Zheng
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, P. R. China
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2
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Wang ZB, Hu HX, Zheng YG. Evaluation of the dissolved oxygen-related electrochemical behavior of pure titanium in acidic fluoride-containing solutions. J Solid State Electrochem 2016. [DOI: 10.1007/s10008-016-3321-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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3
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Zheng YG, Wang ZH. Network-scale effect on synchronizability of fully coupled network with connection delay. Chaos 2016; 26:043103. [PMID: 27131482 DOI: 10.1063/1.4946812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Network-scale effect on synchronizability of fully coupled network with connection delay is investigated in this paper. The master stability function, which governs the stability of synchronization manifold, is first obtained by separating the synchronization manifold direction from other transverse directions. Then, by introducing a new time variable in the master stability function, it is shown the effect of connection delay can be weakened with the increase of network scale, and thus, in contrast to the situation without connection delay, large network scale is more positive to the synchronizability of fully coupled network with connection delay. Those findings are confirmed by the studies on two specific networks with nodes of typical nonlinear dynamical systems.
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Affiliation(s)
- Y G Zheng
- School of Mathematics and Information Science, Nanchang Hangkong University, 330063 Nanchang, Jiangxi, China
| | - Z H Wang
- State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, 210016 Nanjing, China
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Ye HF, Zheng YG, Zhang ZQ, Chen Z, Zhang HW. Water filling and electric field-induced enhancement in the mechanical property of carbon nanotubes. Sci Rep 2015; 5:17537. [PMID: 26621767 PMCID: PMC4664918 DOI: 10.1038/srep17537] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 11/02/2015] [Indexed: 11/09/2022] Open
Abstract
The effects of water filling and electric field on the mechanical property of carbon nanotubes (CNTs) are investigated with molecular dynamics simulations. The simulation results indicate that the water filling and electric field could enhance the elastic modulus but reduce the Poisson's ratio of the CNTs. As for the buckling behaviors, a significant enhancement could be observed in the yield stress and average post-buckling stress of the CNTs. In particular, the enhancement in the yield stress induced by the water filling and electric field could be even higher than that resulted from the solid filling. Moreover, a transition mechanism from the rod instability to shell buckling is shown to explain the nonmonotonic variation of yield stress, and the critical diameter can be tuned through filling the water molecules and applying the electric field. The present findings provide a valuable route for the optimized design and application of the nanoscale functional devices based on the water-filled CNTs.
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Affiliation(s)
- H F Ye
- State Key Laboratory of Structural Analysis for Industrial Equipment, Department of Engineering Mechanics, Faculty of Vehicle Engineering and Mechanics, Dalian University of Technology, Dalian 116024, P. R. China
| | - Y G Zheng
- State Key Laboratory of Structural Analysis for Industrial Equipment, Department of Engineering Mechanics, Faculty of Vehicle Engineering and Mechanics, Dalian University of Technology, Dalian 116024, P. R. China
| | - Z Q Zhang
- Micro/Nano Science and Technology Center, Jiangsu University, Zhenjiang 210013, P.R. China
| | - Z Chen
- State Key Laboratory of Structural Analysis for Industrial Equipment, Department of Engineering Mechanics, Faculty of Vehicle Engineering and Mechanics, Dalian University of Technology, Dalian 116024, P. R. China.,Department of Civil and Environmental Engineering, University of Missouri, Columbia, MO 65211, USA
| | - H W Zhang
- State Key Laboratory of Structural Analysis for Industrial Equipment, Department of Engineering Mechanics, Faculty of Vehicle Engineering and Mechanics, Dalian University of Technology, Dalian 116024, P. R. China
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5
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Liu X, Lu Y, Yang YS, Hu HX, Zheng YG. Electrochemical behavior of phenylalanine and its cobalt complex as corrosion inhibitors for mild steel in H2SO4. RUSS J APPL CHEM+ 2015. [DOI: 10.1134/s1070427215020263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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6
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Zheng YG, Zhao YT, Ye HF, Zhang HW. Size-dependent elastic moduli and vibrational properties of fivefold twinned copper nanowires. Nanotechnology 2014; 25:315701. [PMID: 25030768 DOI: 10.1088/0957-4484/25/31/315701] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Based on atomistic simulations, the elastic moduli and vibration behaviors of fivefold twinned copper nanowires are investigated in this paper. Simulation results show that the elastic (i.e., Young's and shear) moduli exhibit size dependence due to the surface effect. The effective Young's modulus is found to decrease slightly whereas the effective shear modulus increases slightly with the increase in the wire radius. Both moduli tend to approach certain values at a larger radius and can be suitably described by core-shell composite structure models. Furthermore, we show by comparing simulation results and continuum predictions that, provided the effective Young's and shear moduli are used, classic elastic theory can be applied to describe the small-amplitude vibration of fivefold twinned copper nanowires. Moreover, for the transverse vibration, the Timoshenko beam model is more suitable because shear deformation becomes apparent.
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Affiliation(s)
- Y G Zheng
- State Key Laboratory of Structure Analysis for Industrial Equipment, Department of Engineering Mechanics, Faculty of Vehicle Engineering and Mechanics, Dalian University of Technology, Dalian 116024, People's Republic of China
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7
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Wang TB, Zhang NL, Wang SH, Li HY, Chen SW, Zheng YG. Expression of ERCC1 and BRCA1 predict the clinical outcome of non-small cell lung cancer in patients receiving platinum-based chemotherapy. Genet Mol Res 2014; 13:3704-10. [PMID: 24854656 DOI: 10.4238/2014.may.9.15] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We examined mRNA expression levels of ERCC1, BRCA1, RRM1, and human β-tubulin-III (TUBB3) in non-small-cell lung carcinoma (NSCLC) patients and investigated the association between expression of these genes and the clinical outcome of NSCLC treatment. A total of 366 patients who underwent surgery for NSCLC were included in this study. All patients received third-generation platinum-based chemotherapy as first-line treatment. The relative cDNA quantification for ERCC1, RRM1, BRCA1, and TUBB3 was determined using a fluorescence-based, real-time detection method. We found that low expression of ERCC1 and BRCA1 was associated with a good response to platinum-based chemotherapy, with an odds ratio [95% confidence interval (CI)] of 2.09 (1.33-3.27) and 2.92 (1.85-4.62), respectively. Multivariate Cox regression analysis indicated that patients with low expression of ERCC1 and BRCA1 attained a longer overall survival time than those with high expression, with a hazard ratio (95%CI) of 0.42 (0.23-0.77) and 0.39 (0.21-0.71), respectively. However, RMM1 and TUBB2 expressions were not correlated with clinical outcome of NSCLC. In conclusion, we found that low expression of ERCC1 and BRCA1 can be useful for selecting NSCLC patients who would benefit from chemotherapy and warrants further investigation in prospective studies.
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Affiliation(s)
- T B Wang
- Department of Respiratory Medicine, Luoyang Center Hospital Affiliated to Zhengzhou University, Luoyang, China
| | - N L Zhang
- Department of Respiratory Medicine, Luoyang Center Hospital Affiliated to Zhengzhou University, Luoyang, China
| | - S H Wang
- Department of Respiratory Medicine, Luoyang Center Hospital Affiliated to Zhengzhou University, Luoyang, China
| | - H Y Li
- Department of Respiratory Medicine, Luoyang Center Hospital Affiliated to Zhengzhou University, Luoyang, China
| | - S W Chen
- Department of Respiratory Medicine, Luoyang Center Hospital Affiliated to Zhengzhou University, Luoyang, China
| | - Y G Zheng
- Department of Respiratory Medicine, Luoyang Center Hospital Affiliated to Zhengzhou University, Luoyang, China
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8
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Zheng YG, Wang ZH. Time-delay effect on the bursting of the synchronized state of coupled Hindmarsh-Rose neurons. Chaos 2012; 22:043127. [PMID: 23278062 DOI: 10.1063/1.4768664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The time-delay effect on the bursting of the synchronized state of coupled Hindmarsh-Rose neurons is investigated in this paper. The time-delay influence on the structure of the slow manifold is first studied by using the method of stability switch. And then on the basis of the geometric singular perturbation theory, case studies are given to show that the time delay can suppress the bursting oscillation or lead to more complex dynamics. In particular, the mechanism of the transition from bursting oscillation to relaxation oscillation and to chaotic bursting is stated. Numerical results are given to demonstrate the validity of the analytical results.
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Affiliation(s)
- Y G Zheng
- School of Mathematics and Information Science, Nanchang Hangkong University, 330063 Nanchang, Jiangxi, China
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Okafor PC, Liu CB, Zhu YJ, Zheng YG. Corrosion and Corrosion Inhibition Behavior of N80 and P110 Carbon Steels in CO2-Saturated Simulated Formation Water by Rosin Amide Imidazoline. Ind Eng Chem Res 2011. [DOI: 10.1021/ie1024112] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- P. C. Okafor
- State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Road, Shenyang 110016, Liaoning Province, PR China
- Corrosion and Electrochemistry Research Group, Department of Pure and Applied Chemistry, University of Calabar, P. M. B. 1115, Calabar, Nigeria
| | - C. B. Liu
- State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Road, Shenyang 110016, Liaoning Province, PR China
| | - Y. J. Zhu
- State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Road, Shenyang 110016, Liaoning Province, PR China
| | - Y. G. Zheng
- State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Road, Shenyang 110016, Liaoning Province, PR China
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Wang YJ, Zheng YG, Zheng RC, Shen YC. Stability study on the nitrile hydratase of Nocardia sp. 108: From resting cells to crude enzyme preparation. APPL BIOCHEM MICRO+ 2006. [DOI: 10.1134/s0003683806040077] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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11
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Wang YJ, Zheng YG, Zheng RC, Shen YC. Stability study on the nitrile hydratase of Nocardia sp. 108: from resting cell to crude enzyme preparation. Prikl Biokhim Mikrobiol 2006; 42:434-7. [PMID: 17022452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
In recent years, nitrile hydratases (NHases) have drawn increasing attentions due to their critical roles in organic synthesis. In present paper, extensive investigation on the stability and activity of the NHase from Nocardia sp. 108, which is succeed in the industrial application in China, were conducted by the bioconversion of acrylonitrile to acrylamide in a batch manner. Cultivation study demonstrated that biosynthesis of NHase changed significantly with culture time, and the optimal NHase biosynthesis phase was 45 h after inoculation with NHase activity of 1209.8 U/g of biomass. Stability study indicated that crude enzyme preparation both exhibit a good stability when exposed to the pH 7.2 tris-HCl buffer at 4 degrees C for 4 h.
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Affiliation(s)
- Y J Wang
- Institute of Bioengineering, Zhejiang University of Technology, Hangzhou 310014, PR China
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12
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Chan CY, Zheng XD, Chan LY, Cui H, Ginn EWL, Leung YK, Lam HM, Zheng YG, Qin Y, Zhao CS, Wang T, Blake DR, Li YS. Vertical profile and origin of wintertime tropospheric ozone over China during the PEACE-A period. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2004jd004581] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- C. Y. Chan
- Department of Civil and Structural Engineering; Hong Kong Polytechnic University; Hong Kong China
| | - X. D. Zheng
- Chinese Academy of Meteorological Sciences; Beijing China
| | - L. Y. Chan
- Department of Civil and Structural Engineering; Hong Kong Polytechnic University; Hong Kong China
| | - H. Cui
- Department of Civil and Structural Engineering; Hong Kong Polytechnic University; Hong Kong China
| | | | | | - H. M. Lam
- Department of Civil and Structural Engineering; Hong Kong Polytechnic University; Hong Kong China
| | - Y. G. Zheng
- Department of Atmospheric Sciences; Peking University; Beijing China
| | - Y. Qin
- Department of Atmospheric Sciences; Peking University; Beijing China
| | - C. S. Zhao
- Department of Atmospheric Sciences; Peking University; Beijing China
| | - T. Wang
- Department of Civil and Structural Engineering; Hong Kong Polytechnic University; Hong Kong China
| | - D. R. Blake
- Department of Chemistry; University of California; Irvine California USA
| | - Y. S. Li
- Department of Civil and Structural Engineering; Hong Kong Polytechnic University; Hong Kong China
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Chan CY, Chan LY, Zheng YG, Harris JM, Oltmans SJ, Christopher S. Effects of 1997 Indonesian forest fires on tropospheric ozone enhancement, radiative forcing, and temperature change over the Hong Kong region. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2001jd900092] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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14
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Luo GM, Qi DH, Zheng YG, Mu Y, Yan GL, Yang TS, Shen JC. ESR studies on reaction of saccharide with the free radicals generated from the xanthine oxidase/hypoxanthine system containing iron. FEBS Lett 2001; 492:29-32. [PMID: 11248231 DOI: 10.1016/s0014-5793(01)02226-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The free radicals generated from the iron containing system of xanthine oxidase and hypoxanthine (Fe-XO/HX) were directly detected by using spin trapping. It was found that not only superoxide anion (O(2)*-) and hydroxyl radical (OH*), but also alkyl or alkoxyl radicals (R*) were formed when saccharides such as glucose, fructose and sucrose were added into the Fe-XO/HX system. The generated amount of R* was dependent on the kind and concentration of saccharides added into the Fe-XO/HX system and no R* were detected in the absence of saccharides, indicating that there is an interaction between the saccharide molecules and the free radicals generated from the Fe-XO/HX system and saccharide molecules are essential for generating R* in the Fe-XO/HX system. It is expected that the toxicity of R* would be greater than of hydrophilic O(2)*- and OH* because they are liposoluble and their lives are longer and the active sites of biomolecules are closely related with lipophilic phase, thus they can damage cells more seriously than O(2)*- and OH*. The R* generated from the saccharide containing Fe-XO/HX can be effectively scavenged by selenium containing abzyme (Se-abzyme), indicating Se-abzyme is a promising antioxidant.
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Affiliation(s)
- G M Luo
- Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, Jilin University, Changchun, PR China.
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15
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Zheng YG, Hu YG, Zhou BW. [An epidemiologic study of workers with low back pain]. Zhonghua Wai Ke Za Zhi 1994; 32:43-5. [PMID: 8045203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
To evaluate the impact of low back pain we conducted a cross-sectional epidemiologic study of 10087 workers in factories of textile, machinery auto-transportation, clothing and sea cultivation. The prevalence of pain was compared with ages, sexes, duration of employment, types of jobs as well as body posture. The prevalence of low back in males was 13.66%, and in females 8.75% (average 11.53%). The risk factors included lifting, bending, twisting prolonged sitting and vibration as well as moisture and coldness prolonged sitting was. The important contributing factor of low back pain in sedentary workers.
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Zheng YG. [Developmental stenosis of the cervical spinal canal hyperextension injury]. Zhonghua Wai Ke Za Zhi 1992; 29:727-9, 796. [PMID: 1618029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Sixteen cases of cervical spinal cord injury with developmental stenosis of cervical spinal canal were treated. The numbness and quadriplegia of the patients were caused by hyperextension X-ray of the cervical spine showed no fracture or dislocation but the sagittal diameter of the canal and that of the corresponding cervical vertebral body was less than 0.75. All of the patients were treated by operation including laminoplasty on 12 cases. The numbness and quadriplegia in most of the patients were improved obviously after operation. The mechanism of hyperextension injury on the cervical spinal cord was discussed. When spinal column was extended, annulus fibrosus of disk and ligamentum flavum would enfold into the spinal canal and only a slight force would do severe on the cord. Laminoplasty is the recommended treatment for this kind of lesions.
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Affiliation(s)
- Y G Zheng
- Department of Orthopaedics, Affiliated Hospital of Qingdao Medical College
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