后路减压椎弓根螺钉内固定治疗胸腰椎骨折疗效分析

目的:探讨后路减压椎弓根螺钉内固定治疗胸腰椎骨折的疗效。方法:本研究选取了90例胸腰椎骨折患者,按照入院时间顺序不同分为两组,前路组(46例)采取前路减压椎弓根螺钉内固定治疗,后路组(44例)采取后路减压椎弓根螺钉内固定治疗。观察并记录两组患者围手术期参数,术前术后下腰痛功能、神经功能恢复情况及随访12个月期间并发症发生情况,评价后路减压椎弓根螺钉内固定治疗胸腰椎骨折的疗效。结果:后路组在术中失血量、手术时间、住院时间上均明显少于或短于前路组(P0.05);与术前相比,术后两组Oswestry功能障碍指数(ODI)值均明显降低(P0.05)。与术后同时间前路组相比,后路组ODI值均明显低于前路组(P0.05);与术前相比,术后12个月两组神经功能分级整体有所提高(P0.05),但两组间相比,差异没有统计学意义(P0.05);随访12个月期间,两组并发症发生率比较,差异没有统计学意义(P0.05)。结论:采用后路椎弓根螺钉内固定治疗胸腰椎骨折,手术时间短,疗效显著,术中出血量少,预后较好,有利于患者腰椎功能的恢复。     

Structure of an amide bond forming F(420):gamma-glutamyl ligase from Archaeoglobus fulgidus -- a member of a new family of non-ribosomal peptide synthases

F(420) is a flavin-like redox-active coenzyme commonly used by archaea and some eubacteria in a variety of biochemical reactions in methanogenesis, the formation of secondary metabolites, the degradation of nitroaromatic compounds, activation of nitroimidazofurans, and F(420)-dependent photolysis in DNA repair. Coenzyme F(420)-2 biosynthesis from 7,8-didemethyl-8-hydroxy-5-deazariboflavin (Fo) and lactaldehyde involves six enzymatic steps and five proteins (CofA, CofB, CofC, CofD, and CofE). CofE, a F(420)-0:gamma-glutamyl ligase, is responsible for the last two enzymatic steps; it catalyses the GTP-dependent addition of two L-glutamate residues to F(420)-0 to form F(420)-2. CofE is found in archaea, the aerobic actinomycetes, and cyanobacteria. Here, we report the first crystal structure of the apo-F(420)-0:gamma-glutamyl ligase (CofE-AF) from Archaeoglobus fulgidus and its complex with GDP at 2.5 A and 1.35 A resolution, respectively. The structure of CofE-AF reveals a novel protein fold with an intertwined, butterfly-like dimer formed by two-domain monomers. GDP and Mn(2+) are bound within the putative active site in a large groove at the dimer interface. We show that the enzyme adds a glutamate residue to both F(420)-0 and F(420)-1 in two distinct steps. CofE represents the first member of a new structural family of non-ribosomal peptide synthases.     

半伸直位髓内钉联合空心螺钉固定治疗胫骨下1/3螺旋形骨折合并后踝骨折的疗效研究

摘要 目的：探讨半伸直位髓内钉联合空心螺钉固定治疗胫骨下1/3螺旋形骨折合并后踝骨折的疗效。方法：回顾性分析2016年10月至2020年6月期间中国人民解放军陆军第七十三集团军医院收治的60例胫骨下1/3螺旋形骨折合并后踝骨折患者的临床资料,男47例,女13例,年龄18～71岁,平均（53.15±4.06）岁,致伤原因：车祸伤27例,摔伤21例,运动伤12例。根据髓内钉置钉方式不同将其分为两组,半伸直组采用半伸直位髓内钉联合空心螺钉固定（30例）,标准组采用标准髓内钉联合空心螺钉固定（30例）,所有患者术后随访1年。比较两组手术时间、术中出血量、骨折愈合时间、踝关节功能、膝关节功能、疼痛程度、并发症的差异。结果：半伸直组手术时间短于标准组（P<0.05）,两组术中出血量、骨折愈合时间比较无统计学差异（P＞0.05）。两组术后美国足踝外科协会（AOFAS）评分、Karlsson踝关节功能（KAFS）评分、美国纽约特种外科医院(HSS)评分均呈增高趋势（P<0.05）,视觉模拟评分法（VAS）评分均呈降低趋势（P<0.05）,半伸直组术后12周、术后1年VAS评分均低于标准组（P＜0.05）,HSS评分高于标准组（P＜0.05）。两组并发症发生率比较无统计学差异（P＞0.05）。结论：采用半伸直位髓内钉联合空心螺钉固定治疗胫骨下1/3螺旋形骨折合并后踝骨折患者,与标准髓内钉联合空心螺钉固定比较,安全性和促进踝关节恢复的效果相当,且手术用时更短,患者术后疼痛更轻,膝关节功能改善更明显,在治疗中更具优势。     

中西医结合治疗桡骨远端骨折的临床分析

目的:探讨中西医结合治疗桡骨远端骨折的临床治疗效果。方法:选取本院收治的桡骨远端骨折患者60例,将其随机分为对照组和实验组,每组30例。对照组采用切开复位钢板螺钉固定方法治疗,实验组采用切开复位钢板螺钉固定加局部中药外敷治疗。观察和比较两组患者的骨折愈合时间、腕部功能恢复情况以及临床疗效。结果:与对照组比较,实验组患者的骨折愈合时间明显缩短,患肢腕部功能明显改善,差异具有统计学意义(P0.05);实验组的临床总有效率(76.66%)明显高于对照组(65.00%),差异具有统计学意义(P0.05)。结论:中西医结合治疗桡骨远端骨折能够有效缩短骨折愈合时间,明显改善患者的腕部功能,值得临床推广。     

不同手术方式治疗老年股骨粗隆间骨折的疗效分析

目的：回顾分析应用动力髋螺钉（dynamic hip screw,DHS）、股骨近端锁定钢板（locking proximal femur plate,LPFP）、防旋型 股骨近端髓内钉(proximal femoral nail antirotation,PFNA)和人工股骨头置换术（femoral head replacement,FHR）治疗老年股骨粗 隆间骨折的临床疗效。方法：分别应用DHS、LPFP、PFNA、FHR内固定方法治疗112 例老年股骨粗隆间骨折,从手术时间、术中平 均出血量、术后并发症、术后髋关节功能评分方面进行分析。结果：从手术时间,术中出血量和术后并发症上,PFNA 组较其他组 少,差异有统计学意义(P<0.05);DHS 组,LPFP 组和FHR 组间比较差异无统计学意义(P>0.05)。Harris 髋关节功能评分上,PFNA 及人工关节组较其他2 组为优,差异有统计学意义(P<0.05);但PFNA 组和FHR组比较差异无统计学意义(P>0.05)。结论：4 组内 固定方式都有其优点和缺点,应根据骨折的不同类型选择合理的内固定方式。     

Complexity and evolution: What everybody knows

The consensus among evolutionists seems to be (and has been for at least a century) that the morphological complexity of organisms increases in evolution, although almost no empirical evidence for such a trend exists. Most studies of complexity have been theoretical, and the few empirical studies have not, with the exception of certain recent ones, been especially rigorous; reviews are presented of both the theoretical and empirical literature. The paucity of evidence raises the question of what sustains the consensus, and a number of suggestions are offered, including the possibility that certain cultural and/or perceptual biases are at work. In addition, a shift in emphasis from theoretical to empirical inquiry is recommended for the study of complexity, and guidelines for future empirical studies are proposed.     

椎弓根螺钉强化技术联合PVP治疗kummell病的疗效及对患者脊柱稳定性和肢体功能的影响

摘要 目的：探究椎弓根螺钉强化技术联合经皮椎体成形术（PVP）治疗kummell病的疗效及对患者脊柱稳定性和肢体功能的影响。方法：选择2017年1月-2020年12月期间新疆医科大学第六附属医院和海军医科大学第二附属医院收治的64例kummell病患者,按照治疗方法分为PVP组（使用PVP治疗,32例）和强化组（使用椎弓根螺钉强化技术联合PVP治疗,32例）,比较两组围术期指标、脊柱稳定性、肢体功能及并发症。结果：强化组手术时长、术后住院时间长于PVP组,伤椎骨水泥注入量、透视次数、术中出血量多于PVP组,差异有统计学意义（P＜0.05）。末次随访时,两组伤椎局部Cobb角较术前降低,强化组低于PVP组,伤椎椎体前缘高度比较术前升高,强化组高于PVP组,差异有统计学意义（P＜0.05）。末次随访时,两组Roland-Morris功能障碍中文调查表（CRMDQ）、改良版Oswestry功能障碍指数量表（ODI）评分较术前降低,强化组低于PVP组,差异有统计学意义（P＜0.05）。两组随访期间腰背部疼痛、骨水泥渗漏、相邻椎体骨折等并发症差异无统计学意义（P＜0.05）。结论：PVP术治疗kummell病具有时间短、出血少、恢复快、透视次数少等明显优势,但椎弓根螺钉强化技术联合PVP治疗kummell病可以更好的保证脊柱稳定性,促进肢体功能恢复,且不增加并发症发生率。     

Labor and the Human Relationship with Nature: The Naturalization of Politics in the Work of Thomas Henry Huxley, Herbert George Wells, and William Morris

Historically labor has been central to humaninteractions with the environment, yetenvironmentalists pay it scant attention. Indeed, they have been critical of those whoforeground labor in their politics, socialistsin particular. However, environmentalists havefound the nineteenth-century socialist WilliamMorris appealing despite the fact that he wroteextensively on labor. This paper considers theplace of labor in the relationship betweenhumanity and the natural world in the work ofMorris and two of his contemporaries, theeminent scientist Thomas Henry Huxley, and theFabian socialist Herbert George Wells. Isuggest that Morris's conception of labor hasmuch to recommend it to environmentalists whoare also interested in issues of socialjustice.     

Crystal structure of the polyextremophilic alpha-amylase AmyB from Halothermothrix orenii: details of a productive enzyme-substrate complex and an N domain with a role in binding raw starch

The gene for a membrane-bound, halophilic, and thermostable α-amylase, AmyB, from Halothermothrix orenii was cloned and sequenced. The crystal structure shows that, in addition to the typical domain organization of family 13 glycoside hydrolases, AmyB carries an additional N-terminal domain (N domain) that forms a large groove—the N-C groove—some 30 Å away from the active site. The structure of AmyB with the inhibitor acarbose at 1.35 Å resolution shows that a nonasaccharide has been synthesized through successive transglycosylation reactions of acarbose. Unexpectedly, in a complex of wild-type AmyB with α-cyclodextrin and maltoheptaose at 2.2 Å resolution, a maltotetraose molecule is bound in subsites − 1 to + 3, spanning the cleavage point at − 1/+ 1, with the − 1 glucosyl residue present as a ²S_o skew boat. This wild-type AmyB complex was obtained in the presence of a large excess of substrate, a condition under which it is possible to capture Michaelis complexes, which may explain the observed binding across − 1/+ 1 and ring distortion. We observe three methionine side chains that serve as “binding platforms” for glucosyl rings in AmyB, a seemingly rare occurrence in carbohydrate-binding proteins. The structures and results from the biochemical characterization of AmyB and AmyB lacking the N domain show that the N domain increases binding of the enzyme to raw starch. Furthermore, theoretical modeling suggests that the N-C groove can accommodate, spatially and chemically, large substrates such as A-starch.     

Crystal structures of mammalian glutamine synthetases illustrate substrate-induced conformational changes and provide opportunities for drug and herbicide design

Glutamine synthetase (GS) catalyzes the ligation of glutamate and ammonia to form glutamine, with concomitant hydrolysis of ATP. In mammals, the activity eliminates cytotoxic ammonia, at the same time converting neurotoxic glutamate to harmless glutamine; there are a number of links between changes in GS activity and neurodegenerative disorders, such as Alzheimer's disease. In plants, because of its importance in the assimilation and re-assimilation of ammonia, the enzyme is a target of some herbicides. GS is also a central component of bacterial nitrogen metabolism and a potential drug target. Previous studies had investigated the structures of bacterial and plant GSs. In the present publication, we report the first structures of mammalian GSs. The apo form of the canine enzyme was solved by molecular replacement and refined at a resolution of 3 Å. Two structures of human glutamine synthetase represent complexes with: a) phosphate, ADP, and manganese, and b) a phosphorylated form of the inhibitor methionine sulfoximine, ADP and manganese; these structures were refined to resolutions of 2.05 Å and 2.6 Å, respectively. Loop movements near the active site generate more closed forms of the eukaryotic enzymes when substrates are bound; the largest changes are associated with the binding of the nucleotide. Comparisons with earlier structures provide a basis for the design of drugs that are specifically directed at either human or bacterial enzymes. The site of binding the amino acid substrate is highly conserved in bacterial and eukaryotic GSs, whereas the nucleotide binding site varies to a much larger degree. Thus, the latter site offers the best target for specific drug design. Differences between mammalian and plant enzymes are much more subtle, suggesting that herbicides targeting GS must be designed with caution.