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负压封闭引流联合保留臀上动脉浅支的臀大肌肌皮瓣修复骶尾部IV期压疮的临床效果
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作者 夏卫东 屠卓隆 +3 位作者 赵胜 缪爱梅 刘政军 林才 《温州医科大学学报》 CAS 2024年第4期318-322,共5页
目的:探讨负压封闭引流联合保留臀上动脉浅支的臀大肌旋转肌皮瓣修复骶尾部压疮的临床效果。方法:选取2019年6月—2023年10月温州医科大学附属第一医院收治的12例骶尾部压疮患者,其中男7例,女5例,年龄31~86岁。入院后I期予行负压封闭引... 目的:探讨负压封闭引流联合保留臀上动脉浅支的臀大肌旋转肌皮瓣修复骶尾部压疮的临床效果。方法:选取2019年6月—2023年10月温州医科大学附属第一医院收治的12例骶尾部压疮患者,其中男7例,女5例,年龄31~86岁。入院后I期予行负压封闭引流术,4~7 d后行保留臀上动脉浅支的臀大肌肌皮瓣修复创面。观察术后皮瓣成活情况、并发症发生情况,随访观察皮瓣外形、压疮复发情况。结果:本组12例患者,均因长期卧床致骶尾部受压出现IV期压疮,压疮病因:截瘫患者5例,各种原因所致的长期卧床患者7例,其中脑梗死后遗症患者2例,帕金森病患者3例,老年痴呆症患者1例,股骨颈骨折患者1例。病程2周至8年,清创后创面面积为5.0 cm×5.0 cm~10.0 cm×12.0 cm。12例患者术后皮瓣均完全成活,无皮瓣坏死、静脉淤血、创缘开裂等发生。术后随访2~6个月,皮瓣外形较佳、骶尾部软组织饱满、压疮无复发。结论:保留臀上动脉浅支的臀大肌旋转肌皮瓣血运可靠,设计、操作简单,皮瓣可修复面积大,切取不需要离断臀上动脉浅支,供瓣区一般能直接缝合,修复骶尾部压疮效果较佳。 展开更多
关键词 肌皮瓣 iv期压疮 负压封闭引流 创面修复
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IV型车载储氢瓶聚合物内衬材料的氢气渗透性分析
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作者 张晓伟 李玉娥 +1 位作者 华晔 胡法 《中国塑料》 CAS CSCD 北大核心 2024年第4期92-97,共6页
详细总结论述了气体在高分子聚合物材料中的渗透机理,并简要介绍了有关IV型储氢瓶聚合物内衬氢气渗透性的测试方法以及国内外测试标准。基于此,进一步探讨了测试温度、测试压力以及聚合物材料性能对IV型储氢瓶内衬材料氢气渗透性的影响... 详细总结论述了气体在高分子聚合物材料中的渗透机理,并简要介绍了有关IV型储氢瓶聚合物内衬氢气渗透性的测试方法以及国内外测试标准。基于此,进一步探讨了测试温度、测试压力以及聚合物材料性能对IV型储氢瓶内衬材料氢气渗透性的影响,并展望了未来的发展方向。 展开更多
关键词 iv型储氢瓶 聚合物内衬 氢气渗透性 标准
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基于MIMIC-IV构建及评估脓毒症患者近期和远期死亡风险预测模型
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作者 严丹阳 谢茜 +3 位作者 付翔杰 徐道妙 李宁 姚润 《中南大学学报(医学版)》 CAS CSCD 北大核心 2024年第2期256-265,共10页
目的:鉴于脓毒症的高发病率和高病死率,早期识别高风险患者并及时干预至关重要,而现有死亡风险预测模型在操作、适用性和预测长期预后等方面均存在不足。本研究旨在探讨脓毒症患者死亡的危险因素,构建近期和远期死亡风险预测模型。方法... 目的:鉴于脓毒症的高发病率和高病死率,早期识别高风险患者并及时干预至关重要,而现有死亡风险预测模型在操作、适用性和预测长期预后等方面均存在不足。本研究旨在探讨脓毒症患者死亡的危险因素,构建近期和远期死亡风险预测模型。方法:从美国重症监护医学信息数据库IV(Medical Information Mart for Intensive Care-IV,MIMIC-IV)中选取符合脓毒症3.0诊断标准的人群,按7?3的比例随机分为建模组和验证组,分析患者的基线资料。采用单因素Cox回归分析和全子集回归确定脓毒症患者死亡的危险因素并筛选出构建预测模型的变量。分别用时间依赖性曲线下面积(area under the curve,AUC)、校准曲线和决策曲线评估模型的区分度、校准度和临床实用性。结果:共纳入14240例脓毒症患者,28 d和1年病死率分别为21.45%(3054例)和36.50%(5198例)。高龄、女性、高感染相关器官衰竭评分(sepsis-related organ failure assessment,SOFA)、高简明急性生理学评分(simplified acute physiology score II,SAPS II)、心率快、呼吸频率快、脓毒症休克、充血性心力衰竭、慢性阻塞性肺疾病、肝脏疾病、肾脏疾病、糖尿病、恶性肿瘤、高白细胞计数(white blood cell count,WBC)、长凝血酶原时间(prothrombin time,PT)、高血肌酐(serum creatinine,SCr)水平均为脓毒症死亡的危险因素(均P<0.05)。由PT、呼吸频率、体温、合并恶性肿瘤、合并肝脏疾病、脓毒症休克、SAPS II及年龄8个变量构建的模型,其28 d和1年生存的AUC分别为0.717(95%CI 0.710~0.724)和0.716(95%CI 0.707~0.725)。校准曲线和决策曲线表明该模型具有良好的校准度及较好的临床应用价值。结论:基于MIMIC-IV建立的脓毒症患者近期和远期死亡风险预测模型有较好的识别能力,对患者预后风险评估及干预治疗具有一定的临床参考意义。 展开更多
关键词 脓毒症 近期和远期死亡 美国重症监护医学信息数据库iv 预后因素 预测模型
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Low-temperature 3D-printed collagen/chitosan scaffolds loaded with exosomes derived from neural stem cells pretreated with insulin growth factor-1 enhance neural regeneration after traumatic brain injury 被引量:1
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作者 Xiao-Yin Liu Yin-He Feng +7 位作者 Qing-Bo Feng Jian-Yong Zhang Lin Zhong Peng Liu Shan Wang Yan-Ruo Huang Xu-Yi Chen Liang-Xue Zhou 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第9期1990-1998,共9页
There are various clinical treatments for traumatic brain injury,including surgery,drug therapy,and rehabilitation therapy;howeve r,the therapeutic effects are limited.Scaffolds combined with exosomes represent a prom... There are various clinical treatments for traumatic brain injury,including surgery,drug therapy,and rehabilitation therapy;howeve r,the therapeutic effects are limited.Scaffolds combined with exosomes represent a promising but challenging method for improving the repair of traumatic brain injury.In this study,we determined the ability of a novel 3D-printed collagen/chitosan scaffold loaded with exosomes derived from neural stem cells pretreated with insulin-like growth factor-1(3D-CC-INEXOS) to improve traumatic brain injury repair and functional recove ry after traumatic brain injury in rats.Composite scaffolds comprising collagen,chitosan,and exosomes derived from neural stem cells pretreated with insulin-like growth fa ctor-1(INEXOS) continuously released exosomes for 2weeks.Transplantation of 3D-CC-INExos scaffolds significantly improved motor and cognitive functions in a rat traumatic brain injury model,as assessed by the Morris water maze test and modified neurological seve rity scores.In addition,immunofluorescence staining and transmission electron microscopy showed that3D-CC-INExos implantation significantly improved the recove ry of damaged nerve tissue in the injured area.In conclusion,this study suggests that transplanted3D-CC-INExos scaffolds might provide a potential strategy for the treatment of traumatic brain injury and lay a solid foundation for clinical translation. 展开更多
关键词 3D printing angiogenesis chitosan collagen EXOSOMES functional recovery insulin-like growth factor-1 neural regeneration neural stem cells traumatic brain injury
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Active Peptides and Motifs within Collagen and Other ECM Proteins
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作者 Lixin Dai Stanley W. Lue +5 位作者 Isabelle Hansenne-Cervantes Christina Karas Natalia E. Iyke Austin Parish Jing Wang Caitlin M. Zuilkoski 《American Journal of Molecular Biology》 2023年第4期241-260,共20页
Collagens are the most abundant proteins in mammals and form an extracellular matrix (ECM) with other components as the structural support of muscle, skin, corneas and blood vessels etc. Other than providing structura... Collagens are the most abundant proteins in mammals and form an extracellular matrix (ECM) with other components as the structural support of muscle, skin, corneas and blood vessels etc. Other than providing structural support, the ECM exhibits active communication with cells and influences many cellular processes including migration, wound healing, differentiation and cancer metastasis. Though collagen proteins contain highly repetitive primary sequences and defined tertiary structures, more and more studies have shown that many short peptides/motifs within collagen proteins play key roles in various biological processes. These short sequences are effective within triple helical structures or independently as stand-alone molecules resulting from proteolytic degradation. Besides endogenous ECM-derived peptides, many more functional peptides have been produced by tissue processing, chemical synthesis, and recombinant protein production. In this review, we summarize different peptides/motifs identified in collagen and other ECM proteins and discuss their potential for medical, personal care, and cosmetics applications. 展开更多
关键词 collagen Extracellular Matrix PEPTIDES Recombinant Protein
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基于STM32F373的光伏组件IV特性测试系统
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作者 郑巍 艾学忠 +2 位作者 蒙永龙 王明达 汪冬冬 《机电工程技术》 2024年第2期111-115,共5页
为准确方便测量光伏组件的IV特性曲线,设计一款基于STM32F373的光伏组件IV特性测试系统,可测量开路电压、短路电流、IV曲线、PV曲线等。该系统由电流控制单元、信号采集单元、软件处理单元、通信单元、上位机显示单元等组成,采用电子负... 为准确方便测量光伏组件的IV特性曲线,设计一款基于STM32F373的光伏组件IV特性测试系统,可测量开路电压、短路电流、IV曲线、PV曲线等。该系统由电流控制单元、信号采集单元、软件处理单元、通信单元、上位机显示单元等组成,采用电子负载电路,以STM32F373单片机DAC输出来调节恒流的电流,同时采集光伏电池的输出电压,对采集到的数据进行卡尔曼滤波和曲线拟合,将电压、电流、功率生成IV、PV曲线显示在TFT彩屏上。该系统还可将数据远程传输到PC端进行数据分析与曲线观察。结果表明,该系统采集曲线准确且速度快,性能良好,采集一次IV曲线的时间仅需1 s,测量的电压电流误差小于1%。该系统体积小便于携带且内部带有锂电池,可充电,可在室外使用。 展开更多
关键词 STM32F373 光伏组件 iv特性
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Collagen matrix scaffolds:Future perspectives for the management of chronic liver diseases
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作者 Moises Martinez-Castillo Itzel Altamirano-Mendoza +3 位作者 Rafal Zielinski Waldemar Priebe Cristina Piña-Barba Gabriela Gutierrez-Reyes 《World Journal of Clinical Cases》 SCIE 2023年第6期1224-1235,共12页
Approximately 1.5 billion chronic liver disease(CLD)cases have been estimated worldwide,encompassing a wide range of liver damage severities.Moreover,liver disease causes approximately 1.75 million deaths per year.CLD... Approximately 1.5 billion chronic liver disease(CLD)cases have been estimated worldwide,encompassing a wide range of liver damage severities.Moreover,liver disease causes approximately 1.75 million deaths per year.CLD is typically characterized by the silent and progressive deterioration of liver parenchyma due to an incessant inflammatory process,cell death,over deposition of extracellular matrix proteins,and dysregulated regeneration.Overall,these processes impair the correct function of this vital organ.Cirrhosis and liver cancer are the main complications of CLD,which accounts for 3.5%of all deaths worldwide.Liver transplantation is the optimal therapeutic option for advanced liver damage.The liver is one of the most common organs transplanted;however,only 10%of liver transplants are successful.In this context,regenerative medicine has made significant progress in the design of biomaterials,such as collagen matrix scaffolds,to address the limitations of organ transplantation(e.g.,low donation rates and biocompatibility).Thus,it remains crucial to continue with experimental and clinical studies to validate the use of collagen matrix scaffolds in liver disease. 展开更多
关键词 LivER Chronic liver disease collagen matrix scaffold TRANSPLANT MANAGEMENT
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参苓白术散联合桂枝茯苓丸、达格列净治疗2型糖尿病肾病IV期的蛋白尿的随机对照研究
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作者 张杰 董翠婷 +4 位作者 刘园园 肖宗清 张成银 常玲玲 吴汉利 《临床医学进展》 2024年第1期1829-1835,共7页
目的:观察参苓白术散联合桂枝茯苓丸、达格列净治疗2型糖尿病肾病IV期患者蛋白尿的临床疗效。方法:收集于2021年9月~2022年9月潍坊市益都中心医院就诊的诊断为2型糖尿病肾病IV期患者60例。采用随机、对照的临床研究设计分为治疗组和对照... 目的:观察参苓白术散联合桂枝茯苓丸、达格列净治疗2型糖尿病肾病IV期患者蛋白尿的临床疗效。方法:收集于2021年9月~2022年9月潍坊市益都中心医院就诊的诊断为2型糖尿病肾病IV期患者60例。采用随机、对照的临床研究设计分为治疗组和对照组,观察患者症状评分、实验室指标、疾病疗效等指标变化。结果:本研究最终纳入统计分析的治疗组29例、对照组28例。治疗后,治疗组的中医证候、蛋白尿、肾小球滤过率(eGFR)、糖化血红蛋白(HbA1c)、D-二聚体、尿NGAL、低密度脂蛋白疗效优于对照组(P 0.05)。对照组经治后,尿NGAL较治疗前明显下降(P < 0.05),其余指标与治疗前均无差异(P < 0.05)。两组均未见不良反应。结论:参苓白术散联合桂枝茯苓丸、达格列净治疗可减轻DKD IV期患者临床症状,降低蛋白尿、NGAL、糖化血红蛋白、D-二聚体、低密度脂蛋白,保护肾小管及肾小球、改善机体高凝状态及血糖,延缓肾功能下降,提高临床疗效。 展开更多
关键词 参苓白术散 桂枝茯苓丸 达格列净 2型糖尿病肾病iv 随机对照 临床研究
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Injectable collagen scaffold with human umbilical cordderived mesenchymal stem cells promotes functional recovery in patients with spontaneous intracerebral hemorrhage:phase Ⅰ clinical trial
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作者 Xiao-Yin Li Wu-Sheng Deng +6 位作者 Zi-Qi Wang Zheng-Chao Li Shu-Lian Chen Zhen Song Quan Zhang Jin Liang Xu-Yi Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第9期1999-2004,共6页
Animal expe riments have shown that injectable collagen scaffold with human umbilical cord-derived mesenchymal stem cells can promote recovery from spinal cord injury.To investigate whether injectable collagen scaffol... Animal expe riments have shown that injectable collagen scaffold with human umbilical cord-derived mesenchymal stem cells can promote recovery from spinal cord injury.To investigate whether injectable collagen scaffold with human umbilical cord-derived mesenchymal stem cells can be used to treat spontaneous intracerebral hemorrhage,this non-randomized phase I clinical trial recruited patients who met the inclusion criteria and did not meet the exclusion crite ria of spontaneous intracerebral hemorrhage treated in the Characteristic Medical Center of Chinese People’s Armed Police Force from May 2016 to December 2020.Patients were divided into three groups according to the clinical situation and patient benefit:control(n=18),human umbilical cord-derived mesenchymal stem cells(n=4),and combination(n=8).The control group did not receive any transplantation.The human umbilical cord-derived mesenchymal stem cells group received human umbilical cord-derived mesenchymal stem cell transplantation.The combination group received injectable collagen scaffold with human umbilical cord-derived mesenchymal stem cells.Patients who received injectable collagen scaffold with human umbilical cord-derived mesenchymal stem cells had more remarkable improvements in activities of daily living and cognitive function and smaller foci of intra cerebral hemorrhage-related encephalomalacia.Severe adve rse events associated with cell transplantation were not observed.Injectable collagen scaffold with human umbilical cord-derived mesenchymal stem cells appears to have great potential treating spontaneous intracerebral hemorrhage. 展开更多
关键词 clinical trial collagen scaffold efficacy human umbilical cord-derived mesenchymal stem cells human SAFE neurological recovery spontaneous intracerebral hemorrhage TRANSPLANTATION
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Chitosan conduits enriched with fibrin-collagen hydrogel with or without adipose-derived mesenchymal stem cells for the repair of 15-mm-long sciatic nerve defect
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作者 Marwa El Soury óscar Darío García-García +6 位作者 Isabella Tarulli Jesús Chato-Astrain Isabelle Perroteau Stefano Geuna Stefania Raimondo Giovanna Gambarotia Víctor Carriel 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第6期1378-1385,共8页
Hollow conduits of natural or synthetic origins have shown acceptable regeneration results in short nerve gap repair;however,results are still not comparable with the current gold standard technique“autografts”.Holl... Hollow conduits of natural or synthetic origins have shown acceptable regeneration results in short nerve gap repair;however,results are still not comparable with the current gold standard technique“autografts”.Hollow conduits do not provide a successful regeneration outcome when it comes to critical nerve gap repair.Enriching the lumen of conduits with different extracellular materials and cells could provide a better biomimicry of the natural nerve regenerating environment and is expected to ameliorate the conduit performance.In this study,we evaluated nerve regeneration in vivo using hollow chitosan conduits or conduits enriched with fibrin-collagen hydrogels alone or with the further addition of adipose-derived mesenchymal stem cells in a 15 mm rat sciatic nerve transection model.Unexpected changes in the hydrogel consistency and structural stability in vivo led to a failure of nerve regeneration after 15 weeks.Nevertheless,the molecular assessment in the early regeneration phase(7,14,and 28 days)has shown an upregulation of useful regenerative genes in hydrogel enriched conduits compared with the hollow ones.Hydrogels composed of fibrin-collagen were able to upregulate the expression of soluble NRG1,a growth factor that plays an important role in Schwann cell transdifferentiation.The further enrichment with adipose-derived mesenchymal stem cells has led to the upregulation of other important genes such as ErbB2,VEGF-A,BDNF,c-Jun,and ATF3. 展开更多
关键词 adipose-derived stem cells chitosan conduit fibrin and collagen hydrogel nerve regeneration nerve repair neuregulin 1 peripheral nerve sciatic nerve
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Study on the Reparative Effect of Peptide RW3 Binding Active Collagen after Photoelectric Skincare
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作者 Huanmei Dai Dan Shu +8 位作者 Jing Yang Ruocheng Ma Mihui Liu Qiongya Li Wensu Fan Jianlan Liu Mengyu Yang Xiaoyan Li Jie Yu 《Journal of Cosmetics, Dermatological Sciences and Applications》 2023年第3期229-246,共18页
The photoelectric microneedle treatment instrument is also widely used due to the rapid development of medical cosmetology in China in recent years. It also causes a lot of skin discomfort after the consumers carry ou... The photoelectric microneedle treatment instrument is also widely used due to the rapid development of medical cosmetology in China in recent years. It also causes a lot of skin discomfort after the consumers carry out such projects. This study, which combines small molecule active peptides (RW3) and active collagens and imitates the photoelectric treatment through in vitro and in vivo experiment, finds that small molecule active peptides (RW3) and active collagens have different improvement effects on cell proliferation, migration, anti-UV damage, inhibition of ear swelling and inflammation in mice, repair of UV damage and skin damage caused by microneedles. . 展开更多
关键词 Photoelectric Microneedle Treatment PEPTIDE collagen Inflammation REPAIR
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TGF-β1和Collagen-Ⅲ在牦牛感染细粒棘球蚴肝纤维化中的表达
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作者 陈欣怡 严得刚 +5 位作者 梁宏 李菊英 加央次仁 王登云 赵海龙 唐文强 《动物医学进展》 北大核心 2024年第4期45-50,共6页
研究转化生长因子β1(TGF-β1)、Ⅲ型胶原(Collagen-Ⅲ)在牦牛感染细粒棘球蚴导致肝纤维化中的表达及其意义。收集西藏地区40例细粒棘球蚴感染的牦牛肝组织和血清样本,同时收集未感染的肝组织和血清进行对照。采用苏木素-伊红(HE)染色... 研究转化生长因子β1(TGF-β1)、Ⅲ型胶原(Collagen-Ⅲ)在牦牛感染细粒棘球蚴导致肝纤维化中的表达及其意义。收集西藏地区40例细粒棘球蚴感染的牦牛肝组织和血清样本,同时收集未感染的肝组织和血清进行对照。采用苏木素-伊红(HE)染色法和天狼猩红染色法观察牦牛肝脏病理变化和肝纤维化程度;酶联免疫吸附试验(ELISA)和免疫组化法(IHA)分别检测肝组织和血清中TGF-β1、Collagen-Ⅲ的表达水平及分布;RT-PCR检测肝细胞内TGF-β1和Collagen-Ⅲ基因mRNA的相对表达水平。HE染色和天狼猩红染色结果显示,与未感染细粒棘球蚴病牦牛肝组织相比,感染棘球蚴周围的肝组织肝界板细胞破坏,呈虫蚀状,感染肝组织外围纤维化,细粒棘球蚴寄生的牦牛肝脏组织引起组织增生,纤维化;ELISA结果显示感染细粒棘球蚴牦牛血清样中细胞因子TGF-β1、Collagen-Ⅲ的含量明显超过未感染组(P<0.05),且免疫组化的结果显示它们的表达主要存在于细胞基质中;RT-PCR显示细粒棘球蚴感染肝组织中TGF-β1、Collagen-Ⅲ的mRNA相对表达量超出未感染组(P<0.05)。结果表明,细粒棘球蚴感染期间TGF-β1、Collagen-Ⅲ在细粒棘球蚴感染引起的肝纤维化中起重要作用。 展开更多
关键词 转化生长因子Β1 Ⅲ型胶原 细粒棘球蚴病 肝纤维化
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Anti-abrasion collagen fiber-based membrane functionalized by UiO-66-NH_(2)with ultra-high efficiency and stability for oil-in-water emulsions separation
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作者 Xiaoxia Ye Rixin Huang +3 位作者 Zhihong Zheng Juan Liu Jie Chen Yuancai Lv 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期285-297,共13页
Membrane separation strategies offer promising platform for the emulsion separation.However,the low mechanical strength of membrane separation layers and the trade-off between separation flux and efficiency present si... Membrane separation strategies offer promising platform for the emulsion separation.However,the low mechanical strength of membrane separation layers and the trade-off between separation flux and efficiency present significant challenges.In this study,we report a CFM@UiO-66-NH_(2)membrane with high separation flux,efficiency and stability,through utilizing a robust anti-abrasion collagen fiber membrane(CFM)as the multifunctional support and UiO-66-NH_(2)by an in-situ growth as the separation layer.The high mechanical strength of the CFM compensated for the weakness of the separation layer,while the charge-breaking effect of UiO-66-NH_(2),along with the size sieving of its constituent separating layers and the capillary effect of the collagen fibers,contributed to the potential for efficient separation.Additionally,the CFM@UiO-66-NH_(2)membrane exhibited superhydrophilic properties,making it suitable for separating oil-in-water microemulsions and nanoemulsions stabilized by anionic surfactants.The membrane demonstrated remarkable separation efficiencies of up to 99.960%and a separation flux of370.05 L·m^(-2)·h^(-1).Moreover,it exhibits stability,durability,and abrasion resistance,maintaining excellent separation performance even when exposed to strong acids and alkalis without any damage to its structure and performance.After six cycles of reuse,it achieved a separation flux of 417.97 L·m^(-2)·h^(-1)and a separation efficiency of 99.747%.Furthermore,after undergoing 500 cycles of strong abrasion,the separation flux remained at 124.39 L·m^(-2)·h^(-1),with a separation efficiency of 99.992%.These properties make it suitable for the long-term use in harsh operating environments.We attribute these properties to the electrostatic effect resulting from the amino group on UiO-66-NH_(2)and its in-situ growth on the CFM,which forms a size-screening separation layer.Our work highlights the potential of the CFM@UiO-66-NH_(2)membrane as an environmentally friendly size-screening material for the efficient emulsion wastewater separation. 展开更多
关键词 collagen fibers Metal-organic frameworks Oil-in-water emulsion separation Size sieving
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Corneal collagen cross-linking in patients with keratoconus from the Dresden protocol to customized solutions:theoretical basis
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作者 Ciro Caruso Luca D’Andrea +4 位作者 Mario Troisi Michele Rinaldi Raffaele Piscopo Salvatore Troisi Ciro Costagliola 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期951-962,共12页
Keratoconus is an ectatic condition characterized by gradual corneal thinning,corneal protrusion,progressive irregular astigmatism,corneal fibrosis,and visual impairment.The therapeutic options regarding improvement o... Keratoconus is an ectatic condition characterized by gradual corneal thinning,corneal protrusion,progressive irregular astigmatism,corneal fibrosis,and visual impairment.The therapeutic options regarding improvement of visual function include glasses or soft contact lenses correction for initial stages,gas-permeable rigid contact lenses,scleral lenses,implantation of intrastromal corneal ring or corneal transplants for most advanced stages.In keratoconus cases showing disease progression corneal collagen crosslinking(CXL)has been proven to be an effective,minimally invasive and safe procedure.CXL consists of a photochemical reaction of corneal collagen by riboflavin stimulation with ultraviolet A radiation,resulting in stromal crosslinks formation.The aim of this review is to carry out an examination of CXL methods based on theoretical basis and mathematical models,from the original Dresden protocol to the most recent developments in the technique,reporting the changes proposed in the last 15y and examining the advantages and disadvantages of the various treatment protocols.Finally,the limits of non-standardized methods and the perspectives offered by a customization of the treatment are highlighted. 展开更多
关键词 corneal collagen cross linking KERATOCONUS custom fast protocol Dresden protocol lambert-beer law Bunsen-roscoe law
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Calcium-chelating peptides from rabbit bone collagen:characterization,identification and mechanism elucidation
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作者 Fuhuan Yuan Yu Fu +8 位作者 Liang Ma Hankun Zhu Yong Yu Xin Feng Yi Sun Hongjie Dai Xin Liu Zhengfang Liu Yuhao Zhang 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1485-1493,共9页
This study aimed to characterize and identify calcium-chelating peptides from rabbit bone collagen and explore the underlying chelating mechanism.Collagen peptides and calcium were extracted from rabbit bone by instan... This study aimed to characterize and identify calcium-chelating peptides from rabbit bone collagen and explore the underlying chelating mechanism.Collagen peptides and calcium were extracted from rabbit bone by instant ejection steam explosion(ICSE)combined with enzymatic hydrolysis,followed by chelation reaction to prepare rabbit bone peptide-calcium chelate(RBCP-Ca).The chelating sites were further analyzed by liquid chromatography-tandem mass(LC-MS/MS)spectrometry while the chelating mechanism and binding modes were investigated.The structural characterization revealed that RBCP successfully chelated with calcium ions.Furthermore,LC-MS/MS analysis indicated that the binding sites included both acidic amino acids(Asp and Glu)and basic amino acids(Lys and Arg),Interestingly,three binding modes,namely Inter-Linking,Loop-Linking and Mono-Linking were for the first time found,while Inter-Linking mode accounted for the highest proportion(75.1%),suggesting that chelation of calcium ions frequently occurred between two peptides.Overall,this study provides a theoretical basis for the elucidation of chelation mechanism of calcium-chelating peptides. 展开更多
关键词 Rabbit bone collagen peptide Peptide-calcium chelate Chelation mechanism Liquid chromatography-tandem mass(LC-MS/MS)
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Human umbilical cord mesenchymal stem cell-derived exosomes loaded into a composite conduit promote functional recovery after peripheral nerve injury in rats
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作者 Haoshuai Tang Junjin Li +6 位作者 Hongda Wang Jie Ren Han Ding Jun Shang Min Wang Zhijian Wei Shiqing Feng 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期900-907,共8页
Complete transverse injury of peripheral nerves is challenging to treat.Exosomes secreted by human umbilical cord mesenchymal stem cells are considered to play an important role in intercellular communication and regu... Complete transverse injury of peripheral nerves is challenging to treat.Exosomes secreted by human umbilical cord mesenchymal stem cells are considered to play an important role in intercellular communication and regulate tissue regeneration.In previous studies,a collagen/hyaluronic acid sponge was shown to provide a suitable regeneration environment for Schwann cell proliferation and to promote axonal regeneration.This three-dimensional(3D)composite conduit contains a collagen/hyaluronic acid inner sponge enclosed in an electrospun hollow poly(lactic-co-glycolic acid)tube.However,whether there is a synergy between the 3D composite conduit and exosomes in the repair of peripheral nerve injury remains unknown.In this study,we tested a comprehensive strategy for repairing long-gap(10 mm)peripheral nerve injury that combined the 3D composite conduit with human umbilical cord mesenchymal stem cell-derived exosomes.Repair effectiveness was evaluated by sciatic functional index,sciatic nerve compound muscle action potential recording,recovery of muscle mass,measuring the cross-sectional area of the muscle fiber,Masson trichrome staining,and transmission electron microscopy of the regenerated nerve in rats.The results showed that transplantation of the 3D composite conduit loaded with human umbilical cord mesenchymal stem cell-derived exosomes promoted peripheral nerve regeneration and restoration of motor function,similar to autograft transplantation.More CD31-positive endothelial cells were observed in the regenerated nerve after transplantation of the loaded conduit than after transplantation of the conduit without exosomes,which may have contributed to the observed increase in axon regeneration and distal nerve reconnection.Therefore,the use of a 3D composite conduit loaded with human umbilical cord mesenchymal stem cell-derived exosomes represents a promising cell-free therapeutic option for the treatment of peripheral nerve injury. 展开更多
关键词 axon growth collagen EXOSOME human umbilical cord mesenchymal stem cells hyaluronic acid muscular atrophy nerve guidance conduits peripheral nerve regeneration
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Electroacupuncture improves myocardial fibrosis in heart failure rats by attenuating ECM collagen deposition through modulation of TGF-β1/Smads signaling pathway
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作者 Wen-Hui Wang Qian-Lan Zeng +3 位作者 Jiao-Jiao Zhang Hao-Sheng Wu Sheng-Bing Wu Mei-Qi Zhou 《Traditional Medicine Research》 2024年第8期1-10,共10页
Background: To explore the effects of electroacupuncture on cardiac function and myocardial fibrosis in rat models of heart failure, and to elucidate the underlying mechanism of electroacupuncture in heart failure tre... Background: To explore the effects of electroacupuncture on cardiac function and myocardial fibrosis in rat models of heart failure, and to elucidate the underlying mechanism of electroacupuncture in heart failure treatment. Methods: Healthy male Sprague-Dawley rats were allocated into three groups: Sham group, Model group, and electroacupuncture (Model + EA) group, with each group comprising 8 rats. The model underwent a procedure involving the ligation of the left anterior descending coronary artery to induce a model of heart failure. The Model + EA group was used for 7 consecutive days for electroacupuncture of bilateral Shenmen (HT7) and Tongli (HT5), once a day for 30 min each time. Left ventricular parameters in rats were assessed using a small-animal ultrasound machine to analyze changes in left ventricular end-diastolic volume, left ventricular end-systolic volume, left ventricular ejection fraction, and left ventricular fractional shortening. Serum interleukin-1β (IL-1β), cardiac troponin (cTn), and N-terminal brain natriuretic peptide precursor levels were measured using ELISA. Histopathological changes in rat myocardium were observed through HE staining, while collagen deposition in rat myocardial tissue was assessed using the Masson staining method. Picro sirius red staining, immunohistochemical staining, and RT-qPCR were utilized to distinguish between the various types of collagen deposition. The expression level of TGF-β1 and SMAD2/3/4/7 mRNA in rat myocardial tissues was determined using RT-qPCR. Additionally, western blot analysis was conducted to assess the protein expression levels of TGF-β1, SMAD3/7, and p-SMAD3 in rat myocardial tissues. Results: Compared with the Sham group, the left ventricular ejection fraction and left ventricular fractional shortening values of the Model group were significantly decreased (P < 0.01);the left ventricular end-diastolic volume and left ventricular end-systolic volume values were remarkably increased (P < 0.01);serum N-terminal brain natriuretic peptide precursor content was increased (P < 0.01);serum IL-1β and cTn levels were increased (P < 0.01);myocardial collagen volume fraction were increased (P < 0.01);and those of the expression of TGF-β1 and SMAD2/3/4 mRNA was increased (P < 0.01);the expression of SMAD7 mRNA was decreased (P < 0.01);the protein expression levels of TGF-β1, SMAD3, and p-Smad3 were increased (P < 0.01);the protein expression level of SMAD7 was decreased (P < 0.01) in the Model group. Compared to the Model group, the expression levels of the proteins TGF-β1, SMAD3, and p-Smad3 in myocardial tissue were found to be decreased (P < 0.01), and the expression level of the protein SMAD7 was found to be increased (P < 0.01) in the Model + EA group;the collagen volume fraction and deposition of type Ⅰ /Ⅲ collagen were decreased (P < 0.01) in the Model + EA group. Conclusion: Electroacupuncture alleviates myocardial fibrosis in rats with heart failure, and this effect is likely due to attributed to the modulation of the TGF-β1/Smads signaling pathway, which helps reduce collagen deposition in the extracellular matrix. 展开更多
关键词 heart failure ELECTROACUPUNCTURE heart meridian of Hand-Shaoyin collagen deposition TGF-β1/Smads signaling pathway myocardial fibrosis
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智能IV诊断在分析光伏低效子阵中的应用
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作者 卢阳 张宇川 陈星星 《科学与信息化》 2024年第4期36-38,共3页
由于光伏子阵的非线性行为和其对运行环境的依赖性,传统的保护装置可能无法诊断光伏系统低效子阵问题。为此,业内进行了大量研究来克服这一问题的出现。然而,大多数方法不仅耗时较久,还存在较大的电量损失。同时,由于需要大量数据集,还... 由于光伏子阵的非线性行为和其对运行环境的依赖性,传统的保护装置可能无法诊断光伏系统低效子阵问题。为此,业内进行了大量研究来克服这一问题的出现。然而,大多数方法不仅耗时较久,还存在较大的电量损失。同时,由于需要大量数据集,还存在数据过度拟合问题,导致准确率有所欠缺。在本研究中,通过应用华为AI BOOST智能IV诊断3.0,无论是实验评估还是实际应用,相比传统的诊断方法,均取得了较为明显的效果。 展开更多
关键词 光伏发电站 光伏运维 低效子阵 智能iv诊断
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基于MIMIC-IV数据库中发生血流感染的危重疾病患者相关数据构建革兰阴性菌血流感染风险预测模型
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作者 陈秋宇 秦泽辉 +2 位作者 刘享田 叶莉萍 田行瀚 《山东医药》 CAS 2024年第3期51-55,共5页
目的 基于重症医学信息数据库(MIMIC-IV)中发生血流感染的危重疾病患者相关数据构建预测危重疾病患者革兰阴性菌血流感染发生风险预测模型,以期为预测危重疾病患者发生革兰阴性菌血流感染风险提供新的方法。方法 收集MIMIC-IV中2 503例... 目的 基于重症医学信息数据库(MIMIC-IV)中发生血流感染的危重疾病患者相关数据构建预测危重疾病患者革兰阴性菌血流感染发生风险预测模型,以期为预测危重疾病患者发生革兰阴性菌血流感染风险提供新的方法。方法 收集MIMIC-IV中2 503例发生血流感染的危重疾病患者的临床资料及实验室检查指标[血常规(红细胞、白细胞、血小板等)、血生化(钾离子、钙离子、氯离子、碳酸氢根、阴离子间隙和尿素氮等)、凝血功能指标(INR、PT、PTT)]数据。将所有危重疾病患者以7∶3的比例分为训练集(1 752例)和验证集(751例)。在训练集中使用LASSO回归初步筛选出危重疾病患者发生革兰阴性菌血流感染的影响因素,并将筛选出来的影响因素行多因素Logistic回归分析,建立危重疾病患者革兰阴性菌血流感染风险预测模型(列线图模型)。在训练集和验证集中通过受试者工作特征曲线(ROC)、校准曲线和决策曲线(DCA)分别对列线图模型的区分度、一致性、临床适用性进行评价。结果 年龄、患有肿瘤、肝胆系统疾病、嗜酒史、钾离子、钙离子、碳酸氢根、阴离子间隙和尿素氮为危重疾病患者发生革兰阴性菌血流感染风险的影响因素,基于以上影响因素采用Logistic回归分析,构建列线图模型。训练集和验证集中,列线图模型预测危重疾病患者发生革兰阴性菌血流感染的ROC下面积分别为0.711(95%CI 0.667~0.756)、0.705(95%CI 0.678~0.733);校准曲线表明列线图模型预测革兰阴性菌血流感染发生的结果与实际结果之间具有良好的一致性(P=0.764);DCA显示列线图模型具有良好的临床适用性。结论 成功构建了预测危重疾病患者发生革兰阴性菌血流感染风险的列线图模型,该模型预测性能较好,能有效识别血流感染高风险危重疾病患者。 展开更多
关键词 感染风险预测模型 列线图 革兰阴性杆菌感染 血流感染 革兰阴性杆菌血流感染 重症医学信息数据库
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