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71.
摘要 目的:探讨负压引流技术结合腓肠神经营养皮瓣在跟骨骨折钢板内固定术后皮肤软组织缺损的临床效果。方法:回顾性分析我院骨科2012年5月-2020年5月共31例跟骨骨折术后钢板外露,皮肤软组织缺损住院病人。纳入患者均使用负压引流技术结合腓肠神经营养皮瓣修复技术。创面给予彻底清创后行封闭负压吸引引流术,待创面新鲜后以腓肠神经营养皮瓣修复创面。对术后皮瓣成活情况;Maryland功能评分以及BMRC感觉功能评分进行综合评估。结果:术后2周时,28例皮瓣顺利成活,供区与受区伤口愈合良好,干燥、无渗出。3例术后出现皮瓣肿胀,皮瓣颜色发暗,伤口渗出较多,皮瓣边缘坏死,窦道形成等,给予切开引流、加强换药、敏感抗生素控制感染等治疗后,皮瓣成活。术后随访6-24个月皮瓣外观及功能恢复良好,无创面再坏死,裂开,感染等情况出现。其中2例再次入院行皮瓣整形术。术后6个月时,Maryland功能评分:优:17例;良:11例;优良率为:90.3%。BMRC感觉功能评分:S3-S4:20例;S2:8例;S1:3例。结论:腓肠神经营养皮瓣联合封闭负压吸引技术在跟骨骨折钢板内固定术后皮肤软组织缺损的治疗中能够缩短治疗时间,操作简单,疗效确切,可获得良好的修复效果。 相似文献
72.
Daisuke Yamane-Koshizawa Sotaro Fujii Takahiro Maruno Yuji Kobayashi Masaru Yamanaka Satoshi Wakai 《Bioscience, biotechnology, and biochemistry》2018,82(2):304-311
AVCP cytochrome c′ from mesophilic Allochromatium vinosum exhibits lower stability than a thermophilic counterpart, Hydrogenophilus thermoluteolus cytochrome c′ (PHCP), in which the six specific amino acid residues that are not conserved in AVCP are responsible for its stability. Here we measured the stability of AVCP variants carrying these specific residues instead of the original AVCP ones. Among the six single AVCP variants, all of which formed a dimeric structure similar to that of the wild-type, three were successfully stabilized compared with the wild-type, while one showed lower stability than the wild-type. In addition, the most stabilized and destabilized AVCP variants could bind CO, similar to the wild-type. These results indicated that mesophilic AVCP could be stabilized through specific three mutations modeled by the thermophilic counterpart, PHCP, without changing the CO binding ability. 相似文献
73.
74.
The aggregation of biotherapeutics is a major hindrance to the development of successful drug candidates; however, the propensity to aggregate is often identified too late in the development phase to permit modification to the protein's sequence. Incorporating rational design for the stability of proteins in early discovery has numerous benefits. We engineered out aggregation-prone regions on the Fab domain of a therapeutic monoclonal antibody, bevacizumab, to rationally design a biobetter drug candidate. With the purpose of stabilizing bevacizumab with respect to aggregation, 2 strategies were undertaken: single point mutations of aggregation-prone residues and engineering a glycosylation site near aggregation-prone residues to mask these residues with a carbohydrate moiety. Both of these approaches lead to comparable decreases in aggregation, with an up to 4-fold reduction in monomer loss. These single mutations and the new glycosylation pattern of the Fab domain do not modify binding to the target. Biobetters with increased stability against aggregation can therefore be generated in a rational manner, by either removing or masking the aggregation-prone region or crowding out protein-protein interactions. 相似文献
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76.
Michelle F Griffin Peter E Butler Alexander M Seifalian Deepak M Kalaskar 《World journal of stem cells》2015,7(1):37-50
Stem cells are capable of long-term self-renewal and differentiation into specialised cell types, making them an ideal candidate for a cell source for regenerative medicine. The control of stem cell fate has become a major area of interest in the field of regenerative medicine and therapeutic intervention. Conventional methods of chemically inducing stem cells into specific lineages is being challenged by the advances in biomaterial technology, with evidence highlighting that material properties are capable of driving stem cell fate. Materials are being designed to mimic the clues stem cells receive in their in vivo stem cell niche including topographical and chemical instructions. Nanotopographical clues that mimic the extracellular matrix(ECM) in vivo have shown to regulate stem cell differentiation. The delivery of ECM components on biomaterials in the form of short peptides sequences has also proved successful in directing stem cell lineage. Growth factors responsible for controlling stem cell fate in vivo have also been delivered via biomaterials to provide clues to determine stem cell differentiation. An alternative approach to guide stem cells fate is to provide genetic clues including delivering DNA plasmids and small interfering RNAs via scaffolds. This review, aims to provide an overview of the topographical, chemical and molecular clues that biomaterials can provide to guide stem cell fate. The promising features and challenges of such approaches will be highlighted, to provide directions for future advancements in this exciting area of stem cell translation for regenerative medicine. 相似文献
77.
Thomas Rademacher Markus Sack Daniel Blessing Rainer Fischer Tanja Holland Johannes Buyel 《Plant biotechnology journal》2019,17(8):1560-1566
Industrial plant biotechnology applications include the production of sustainable fuels, complex metabolites and recombinant proteins, but process development can be impaired by a lack of reliable and scalable screening methods. Here, we describe a rapid and versatile expression system which involves the infusion of Agrobacterium tumefaciens into three‐dimensional, porous plant cell aggregates deprived of cultivation medium, which we have termed plant cell packs (PCPs). This approach is compatible with different plant species such as Nicotiana tabacum BY2, Nicotiana benthamiana or Daucus carota and 10‐times more effective than transient expression in liquid plant cell culture. We found that the expression of several proteins was similar in PCPs and intact plants, for example, 47 and 55 mg/kg for antibody 2G12 expressed in BY2 PCPs and N. tabacum plants respectively. Additionally, the expression of specific enzymes can either increase the content of natural plant metabolites or be used to synthesize novel small molecules in the PCPs. The PCP method is currently scalable from a microtiter plate format suitable for high‐throughput screening to 150‐mL columns suitable for initial product preparation. It therefore combined the speed of transient expression in plants with the throughput of microbial screening systems. Plant cell packs therefore provide a convenient new platform for synthetic biology approaches, metabolic engineering and conventional recombinant protein expression techniques that require the multiplex analysis of several dozen up to hundreds of constructs for efficient product and process development. 相似文献
78.
[背景]解脂耶罗维亚酵母属于产油微生物,大量研究表明该酵母能够高产长链脂肪酸和油脂,但是应用该酵母合成超长链脂肪酸仍待研究。[目的]工程化解脂耶罗维亚酵母合成高值超长链脂肪酸,并研究温度对脂肪酸合成的影响。[方法]合成密码子优化的拟南芥(Arabidopsis thaliana)延长酶基因AtFAE1、非洲芥菜(Brassica tournefortii)延长酶基因BtFAE1和碎米芥属植物Cardamine graeca的延长酶基因CgKCS,分别构建质粒pYLEX1-AtFAE1、pYLEX1-BtFAE1、pYLEX1-CgKCS和pYLEX1-AtFAE1-BtFAE1-CgKCS。以解脂耶罗维亚酵母菌株Po1g为宿主,通过化学法分别转化上述4个质粒,获得工程菌Po1g-AtFAE1、Po1g-BtFAE1、Po1g-CgKCS和Po1g-AtFAE1-BtFAE1-CgKCS,比较评价超长链脂肪酸的合成。在此基础上,过表达内源二酯酰甘油酰基转移酶基因DGAT1(diacylglycerol acyltransferase)提高产油量,并研究温度对生物量、产油、脂肪酸组成的影响... 相似文献
79.
Veronica Rodriguez-Rivera John W. Weidner Michael J. Yost 《Journal of visualized experiments : JoVE》2016,(108)
Tissue scaffolds play a crucial role in the tissue regeneration process. The ideal scaffold must fulfill several requirements such as having proper composition, targeted modulus, and well-defined architectural features. Biomaterials that recapitulate the intrinsic architecture of in vivo tissue are vital for studying diseases as well as to facilitate the regeneration of lost and malformed soft tissue. A novel biofabrication technique was developed which combines state of the art imaging, three-dimensional (3D) printing, and selective enzymatic activity to create a new generation of biomaterials for research and clinical application. The developed material, Bovine Serum Albumin rubber, is reaction injected into a mold that upholds specific geometrical features. This sacrificial material allows the adequate transfer of architectural features to a natural scaffold material. The prototype consists of a 3D collagen scaffold with 4 and 3 mm channels that represent a branched architecture. This paper emphasizes the use of this biofabrication technique for the generation of natural constructs. This protocol utilizes a computer-aided software (CAD) to manufacture a solid mold which will be reaction injected with BSA rubber followed by the enzymatic digestion of the rubber, leaving its architectural features within the scaffold material. 相似文献
80.
Yarrowia lipolytica is a biotechnological chassis for the production of a range of products, such as microbial oils and organic acids. However, it is unable to consume xylose, the major pentose in lignocellulosic hydrolysates, which are considered a preferred carbon source for bioprocesses due to their low cost, wide abundance and high sugar content.Here, we engineered Y. lipolytica to metabolize xylose to produce lipids or citric acid. The overexpression of xylose reductase and xylitol dehydrogenase from Scheffersomyces stipitis were necessary but not sufficient to permit growth. The additional overexpression of the endogenous xylulokinase enabled identical growth as the wild type strain in glucose. This mutant was able to produce up to 80 g/L of citric acid from xylose. Transferring these modifications to a lipid-overproducing strain boosted the production of lipids from xylose. This is the first step towards a consolidated bioprocess to produce chemicals and fuels from lignocellulosic materials. 相似文献