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1.
Heliyon ; 6(3): e03609, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32258467

RESUMO

As one of the key components to support all the magnet coils, the GS faces engineering challenge to its operational safety throughout the design, qualification and manufacturing process as a result of extreme loading condition. The structural safety of GS was confirmed by both the FEM analysis and the semi-prototype engineering test after a long time of design, qualification, manufacture and assembly. Welding the cooling pipe to the flexible plate without obvious deformation as well as tightening uniformly and precisely all the tie rods to clamp the plates were carried out successfully during manufacturing. The result of final vacuum leakage test indicates that the GS can not only meet the ITER vacuum requirement but also have no slow out-gassing. The first set of GS which has passed the ITER acceptance test is to be delivered to ITER construction site soon.

2.
Zhonghua Yi Xue Za Zhi ; 97(17): 1320-1323, 2017 May 09.
Artigo em Chinês | MEDLINE | ID: mdl-28482434

RESUMO

Objective: To investigate the clinical characteristics and surgical treatment of cervical spondylotic amyotrophy. Methods: Thirteen patients(13 man) with proximal (10) and distal(3) cervical spondylotic amyotrophy between November 2014 and September 2016 were included in this study. The average age of the patients was 55 (range, 47-66) years. The sex, age, clinical course, type of amyotrophy, lesion segment and postdecompression improvement in muscle power were reviewed. Results: Of 13 cervical spondylotic amyotrophy patients, 9 were performed on with cervical disectomy, 2 were performed on with cervical posterior operation, 2 remainding patients received nonoperative treatment. Cervical spondylotic amyotrophy patients were followed up 6-22 (average 10.6) months, muscle power of 4 patients (all proximal-type)were improved completely (the average recovery time were 4.4 months), muscle power of 6 patients were improved uncompletely, 1 patients failed to improve, the 2 remainding patients received nonoperative treatment had no change. Conclusion: Cervical spondylotic amyotrophy as a rare type of cervical spondylotic disorder, It should distinguish cervical spondylotic amyotrophy from amyotrophic lateral sclerosis, especially in the early stage of amyotrophic lateral sclerosis. A surgical treatment is recommended as the first line of proximal-type CSA, especially those with serious compression. It is important that clinicians should be aware that distal-type CSA had a poor results, resulting in a lower lower satisfaction, especially those with no, or insignificant, sensory disturbance.


Assuntos
Atrofia Muscular Espinal , Idoso , Esclerose Lateral Amiotrófica/diagnóstico , Vértebras Cervicais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia Muscular , Atrofia Muscular Espinal/diagnóstico , Atrofia Muscular Espinal/terapia , Espondilose , Resultado do Tratamento
3.
Folia Morphol (Warsz) ; 75(4): 493-502, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27830875

RESUMO

In adults, the oblique cord or chorda obliqua separates the origins of the flexor pollicis longus (FPL) and flexor digitorum profundus (FDP) muscles from the supinator muscle and elbow joint. This study examined the topographic anatomy of the oblique cord and related muscles in foetuses. Semiserial sections of five mid-term foetuses of gestational age (GA) 14-16 weeks and 12 late-stage foetuses of GA 28-30 weeks were histologically examined and three forearms at GA 30 weeks were macroscopically evaluated. Late-stage foetuses showed a fascial structure between the supinator and FDP muscles. The latter extended proximally to the elbow joint and the muscle origin thickened the distal, ulnar part of the capsule. The FPL origin also extended proximally but did not reach the joint capsule. These morphologies were consistent with macroscopic examinations. The brachialis muscle was widely inserted into the proximal, anterior part of the capsule. In addition, the medial collateral ligament was not covered by the pronator-flexor muscles but by the triceps brachii muscle. The oblique cord apparently did not form prenatally. After birth, the proximal parts of the FDP and FPL muscles were likely replaced by collagenous tissues, providing a specific type of intermuscular septum i.e., the oblique cord. This type of muscle-ligament transition was observed in the annular ligament of the radius. The foetal elbow joint was characterised by strong support by the FDP, brachialis and triceps brachii muscles. Therefore, the foetal elbow is not a miniature version of the adult elbow.


Assuntos
Ligamentos Redondos , Articulação do Cotovelo , Antebraço , Humanos , Músculo Esquelético , Rádio (Anatomia)
4.
Zhonghua Yi Xue Za Zhi ; 96(23): 1806-10, 2016 Jun 21.
Artigo em Chinês | MEDLINE | ID: mdl-27356786

RESUMO

OBJECTIVE: To explore the rules of the anatomic morphology between vertebral artery tortuosity and transverse foramen. METHODS: From January 2012 to December 2015, 60 patients with vertebral artery tortuosity by means of analyzing the image data and basic clinic information as the observation group, and 50 patients randomly selected exclusive of vertebral artery tortuosity, absence of vertebral artery, vertebral artery aneurysm, cervical decomposition incomplete deformity and oral cavity prosthesis artifacts as the control group, the basic clinical information was collected; the transverse foramen area (TF) and vertebral artery cross-sectional area (VA) of the vertebral artery were measured in the observation group and the control group; internal diameter of vertebral artery tortuosity, length of vertebral artery were measured and; twisting coefficient (s)of the vertebral artery was calculated.Then the difference of the above-mentioned statistics was acquired. RESULTS: The C4 TF (25.91±10.13) mm and C6 TF(31.93±17.91) mm of the affected segment of the observation group were significantly higher than those in the control group[(22.11±8.67) mm, (27.19±7.89) mm] (P<0.05); VA and TF were positively correlated.The average age[(68.25±12.03) years], blood pressure (45 cases)of the observation group and the proportion of the menopausal women (39 cases)were higher than those in the control group[(61.32±11.32) years, 23/22](P<0.05). CONCLUSIONS: The area of transverse foramen of C4 and C6 could be affected by vertebral artery tortuosity. It might be related to the occurrence of bone degeneration around C6 and C4.The risk factors of the expansion of the transverse foramen might be advanced age, hypertension and menopausal women.


Assuntos
Vértebras Cervicais , Artéria Vertebral , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Vértebras Cervicais/diagnóstico por imagem , Feminino , Humanos , Hipertensão , Menopausa , Pessoa de Meia-Idade , Boca , Implantação de Prótese , Fatores de Risco , Artéria Vertebral/anatomia & histologia , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/fisiologia
5.
Nanoscale ; 8(1): 333-41, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26612683

RESUMO

In order to understand and imitate the more complex bio-processes and fascinating functions in nature, protein self-assembly has been studied and has attracted more and more interest in recent years. Artificial self-assemblies of proteins have been constructed through many strategies. However, the design of complicated protein self-assemblies utilizing the special profile of building blocks remains a challenge. We herein report linear and 2D nanostructures constructed from a V shape SMAC protein and induced by metal coordination. Zigzag nanowires and wavy 2D nanostructures have been demonstrated by AFM and TEM. The zigzag nanowires can translate to a 2D nanostructure with an excess of metal ions, which reveals the step by step assembly process. Fluorescence and UV/Vis spectra have also been obtained to further study the mechanism and process of self-assembly. Upon the protein nanostructure, fluorescence resonance energy transfer (FRET) could also be detected using fluorescein modified proteins as building blocks. This article provides an approach for designing and controlling self-assembled protein nanostructures with a distinctive topological morphology.

6.
Plant Physiol ; 77(2): 370-3, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16664060

RESUMO

The ability of the wheat germ initiation factors and ribosomes to serve as substrates for a wheat germ protein kinase (Yan and Tao 1982 J Biol Chem 257: 7037-7043) has been investigated. The wheat germ kinase catalyzes the phosphorylation of the 42,000 dalton subunit of eukaryotic initiation factor (eIF)-2 and the 107,000 dalton subunit of eIF-3. Other initiation factors, eIF-4B and eIF-4A, and elongation factors, EF-1 and EF-2, are not phosphorylated by the kinase. Quantitative analysis indicates that the kinase catalyzes the incorporation of about 0.5 to 0.6 mole of phosphate per mole of the 42,000 dalton subunit of eIF-2 and about 6 moles of phosphate per mole of the 107,000 dalton subunit of eIF-3. Three proteins (M(r) = 38,000, 14,800, and 12,600) of the 60S ribosomal subunit are phosphorylated by the kinase, but none of the 40S ribosomal proteins are substrates of the kinase. No effects of phosphorylation on the activities of eIF-2, eIF-3, or 60S ribosomal subunits could be demonstrated in vitro.

7.
J Biol Chem ; 259(8): 5087-92, 1984 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-6325419

RESUMO

Two forms of pyrophosphate:D-fructose-6-phosphate 1-phosphotransferase have been isolated from wheat seedlings. One of these enzymes, termed PFP-1, has been purified to homogeneity. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicates that the enzyme is composed of two different polypeptide chains of Mr = 67,000 (alpha) and 60,000 (beta). PFP-1 has been assigned a molecular structure consisting of alpha 2 beta 2 based on an estimated Mr of 234,000 for the native enzyme. PFP-2, the other form of phosphotransferase, has also been purified extensively. Preliminary data suggest that the active form of PFP-2 is probably a dimer of a polypeptide chain of Mr = 60,000. Immunological studies indicate that the two enzyme preparations share common antigenic determinants. The two forms of enzyme have very similar kinetic properties. The phosphotransferases are activated by fructose 2,6-bisphosphate (Fru-2,6-P2) which lowers the Km of the enzymes for fructose 6-phosphate but not that for PPi. Interestingly, PFP-1 is significantly more active than PFP-2 in the absence of Fru-2,6-P2. Also, PFP-1 exhibits a greater affinity (Ka = 7 nM) than PFP-2 (Ka = 26 nM) for the activator. Based on kinetic, immunological, and physicochemical parameters, it is suggested that the two enzymic forms are related in that they share the same catalytic moiety, i.e. the 60,000-dalton or beta subunit. The beta subunit when in complex formation with the alpha subunit, as in PFP-1, becomes more active in the absence of Fru-2,6-P2 as well as exhibits a greater sensitivity toward the effector.


Assuntos
Frutosedifosfatos/farmacologia , Hexosedifosfatos/farmacologia , Isoenzimas/metabolismo , Fosfotransferases/metabolismo , Plantas/enzimologia , Ativação Enzimática , Concentração de Íons de Hidrogênio , Imunodifusão , Isoenzimas/isolamento & purificação , Cinética , Fosfotransferases/isolamento & purificação , Triticum/enzimologia
8.
Biochemistry ; 22(23): 5340-6, 1983 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-6652066

RESUMO

The reversibility of the reactions catalyzed by the wheat germ kinase and the cyclic AMP independent protein kinases isolated from human erythrocytes (casein kinases A and G) and rabbit skeletal muscle (casein kinases I and II) has been investigated. The reverse reaction requires ADP, Mg2+, phosphoprotein, and kinase and results in the formation of ATP from the phosphoprotein and ADP. The requirement for ADP in the wheat germ kinase and casein kinases II and G catalyzed reactions appears to be nonspecific. These kinases can also utilize GDP, IDP, and UDP as phosphoryl acceptors. Studies with the wheat germ protein T-substrate indicate that the phosphorylation of this protein substrate by the kinases is fully reversible. By contrast, the phosphorylation of phosvitin and casein is only partially reversible. Since the T-substrate is found to contain multiple phosphorylation sites and can serve as phosphoryl acceptor for the various kinases, the specificity of the phosphorylation of the substrate by the kinases is examined by way of the reverse reaction. The wheat germ kinase, casein kinase G, and casein kinase II appear to phosphorylate the same sites on the T-substrate as they are capable of completely dephosphorylating each other's 32P-T-substrate. Each of these kinases can catalyze the incorporation of 12 mol of 32P/48 000 g of T-substrate. In contrast, casein kinases A and I can incorporate only 6 mol of 32P/48 000 g of T-substrate. Studies on the reverse reactions suggest that these phosphorylation sites may be the same for both enzymes.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Eritrócitos/enzimologia , Músculos/enzimologia , Fosfoproteínas , Proteínas de Plantas/metabolismo , Proteínas Quinases/metabolismo , Triticum/análise , Animais , Heparina/farmacologia , Humanos , Cinética , Fosforilação , Coelhos , Especificidade por Substrato
9.
J Biol Chem ; 257(12): 7044-9, 1982 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-6953073

RESUMO

An endogenous phosphoryl acceptor has been purified 138-fold from wheat germ extracts. This protein, termed T-substrate, is far more effective than casein or phosvitin as a phosphoryl acceptor for a wheat germ kinase recently purified by our laboratory. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicates that the T-substrate preparation is not homogeneous. The T-substrate, which migrates at a Mr = 48,000, constitutes about 90% of the total protein stain on the gel and is the only protein component which is phosphorylated by the wheat germ kinase. The hydrodynamic properties of the T-substrate have been determined by gel filtration and glycerol density gradient centrifugation. The protein exhibits a Stokes radius of 65.5 A, a sedimentation coefficient of 3.85 S, a frictional ratio of 2.11, and a molecular weight of approximately 104,000. The results suggest that the wheat germ T-substrate is a dimer. The protein exhibits a greater substrate specificity for the wheat germ kinase than for the cyclic AMP-dependent and several independent protein kinases isolated from rabbit skeletal muscle and human erythrocytes. The T-substrate can be maximally phosphorylated by the wheat germ kinase to the extent of about 8 mol of phosphate/48,000 g of protein. Complete dephosphorylation of the phospho-T-substrate occurred upon treatment with phosphatases. The phosphorylated amino acid was identified by high voltage electrophoresis of an acid hydrolysate of 32P-T-substrate. The results indicate that phosphorylation occurs mainly on the seryl residues of T-substrate.


Assuntos
Fosfoproteínas , Proteínas de Plantas/isolamento & purificação , Plantas/enzimologia , Proteínas Quinases/metabolismo , Animais , Caseína Quinases , Eritrócitos/enzimologia , Humanos , Cinética , Peso Molecular , Músculos/enzimologia , Fosforilação , Coelhos , Especificidade por Substrato , Triticum/enzimologia
10.
J Biol Chem ; 257(12): 7037-43, 1982 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-6282829

RESUMO

A cyclic AMP-independent protein kinase has been purified from wheat germ extracts. The enzyme catalyzes the phosphorylation of casein and phosvitin but not protamine, histone, or bovine serum albumin. However, the best substrate for the kinase appears to be that of an endogenous wheat germ protein. The kinase can utilize both ATP and GTP as phosphoryl donors. A molecular weight of 36,000-38,000 had been estimated for the kinase by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and by glycerol density gradient centrifugation and gel filtration in the presence of 0.5 M KCl. In the presence of low salt, however, the molecular weight of the kinase appears to double. In isoelectrofocusing, the kinase exhibits a pI of about 6.5. The activity of the kinase is strongly inhibited by spermine and heparin. Spermidine is slightly stimulatory at low concentrations but inhibitory at high concentrations. High concentrations of putrescine also inhibit the kinase activity, but not to the extent observed with the other polyamines. Both spermine and spermidine appear to enhance the kinase activity at low Mg2+ concentrations. The result suggests that these polyamines could partially replace Mg2+ for kinase activity.


Assuntos
Plantas/enzimologia , Proteínas Quinases/isolamento & purificação , AMP Cíclico/farmacologia , Heparina/farmacologia , Cinética , Magnésio/farmacologia , Peso Molecular , Proteínas Quinases/metabolismo , Putrescina/farmacologia , Espermidina/farmacologia , Espermina/farmacologia , Especificidade por Substrato , Triticum/enzimologia
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