胶原酶对人根面牙本质胶原蛋白降解作用的实验研究

目的：探讨胶原酶对脱矿后的人牙根面牙本质胶原蛋白的降解作用。方法：根面牙本质标本用pH5.0的乳酸37℃孵育脱矿。分别于第1、7、14、21和28天取孵育液，10000r/min，4℃离心，上清液作Ca^2 测定和羟脯胺酸分析。脱矿后的标本加入pH7.4的胶原酶溶液，37℃孵育7d。孵育液10000r/min、4℃离心，上清液作羟脯胺酸分析。结果：随着时间的延长，Ca^2 释放量逐渐增加，增加量有显著性差异（P＜0．05）；胶原蛋白的释放量随时间的延长而增加，但增加量无显著性差异。如胶原酶降解后，当Ca^2 少于80.01μmol/cm^2时，胶原蛋白释放量增加明显（P＜0．001）；以后虽然Ca^2 浓度增加，胶原蛋白的增加量无显著性差异。结论：胶原酶对根面牙本质胶原蛋白的降解作用与Ca^2 密切相关。保留龈损区的矿物质对于预防胶原纤维的降解、促进早期根面龋的再矿化是非常重要的。     

Matrix metalloproteinase-8 (MMP-8) is the major collagenase in human dentin

Objective

Previously an unidentified collagenolytic metalloprotease together with gelatinase (matrix metalloproteinase-2, MMP-2), and enamelysin (MMP-20) have been detected in human dentin. The aim of the study was to characterize dentinal collagenolytic enzymes. Furthermore, we hypothesized that the dentinal MMPs are protected by the mineral phase, and studied the stability of dentinal MMPs.

Design

To characterize dentinal collagenolytic enzymes, we used Western blotting with specific antibodies against MMP collagenases (MMP-1, -8, and -13) and cathepsin K. MMP-8 immunofluorometric assay (IFMA) was also used for MMP-8 detection, and functional collagenase activity was examined with type I collagen degradation assay. The stability of dentinal MMPs was examined by autoclaving dentin blocks before protein extraction and subsequent examination of protein levels and the activities of dentin collagenase and gelatinases.

Results

MMP-8 (collagenase-2) was detected in dentin both with Western blot and IFMA, and dentinal samples also cleaved the intact type I collagen into characteristic 3/4(αA)-cleavage products in vitro. No other collagenases or cathepsin K were detected. In autoclaved samples no MMP-8 was found, but gelatinase activity was observed in protein fractions of mineralized dentin.

Conclusions

MMP-8 represents the major collagenase in human dentin. Unlike MMP-8, dentinal gelatinases can be detected after autoclave treatment of dentin, indicating their high resistance to external sample treatment procedures.     

Postapproval clinical experience in the treatment of Dupuytren’s contracture with collagenase clostridium histolyticum (CCH): the first 1,000 days

Dupuytren’s contracture is a benign fibromatosis of the palmar and digital fascia of the hand of uncertain etiology, resulting in nodules and cords beneath the skin of the palm of the hands that may lead to the development of contractures. Surgical intervention is often considered when metacarpophalangeal (MP) joint contracture is 30° or more, or when there is any degree of proximal interphalangeal (PIP) joint contracture. Collagenase clostridium histolyticum (CCH) is a nonsurgical, minimally invasive enzymatic drug indicated for the treatment of adult patients with Dupuytren’s contracture (DC) and palpable cord. CCH has been available for approximately 3.5 years, and postapproval experience indicates that the effectiveness of CCH is equivalent to or better than efficacy observed in clinical trials, as seen by lower injection rates to achieve clinical success. Postapproval experience has shown a risk-benefit profile that favors CCH for patients not indicated for surgery based on current recommendations and shows also that treating earlier-stage vs later-stage joint contracture results in significantly better outcomes on average. Postapproval surveillance reveals a safety profile similar to that observed in clinical trials. Nonserious adverse events are mainly local reactions; tendon rupture, a serious adverse event, is reported rarely in the clinical practice setting and at a lower rate than in clinical trials. Risk Evaluation and Mitigation Strategy (REMS) training is designed to mitigate benefit vs risk to achieve safe and effective use of CCH.     

胶原酶治疗腰椎间盘突出症文献计量 与可视化分析

目的 通过CiteSpace软件分析国内胶原酶治疗腰椎间盘突出症的研究历史和现状。方法 检索1984年至2022年中国知网（CNKI）数据库中关于胶原酶治疗腰椎间盘突出症的文献,应用CiteSpace5.8.R3软件建立可视化科学知识图谱。结果 纳入符合主题的文献1022篇,1994年后发文量逐渐增长,在2005年和2006年年发文量达到最高;发文量排名前3的作者是刘延青、王执民、宋文阁;发文排名前2的省份是山东省和广东省;排名前4的关键词聚类标签是“#0 胶原酶,#1 盘内注射,#2 靶点,#3 臭氧”,关键词突现分析表明“臭氧”具有最大突现强度,“等离子、射频热凝、靶点”突现强度持续至2022年;胶原酶治疗腰椎间盘突出症相关研究经历了持续增长、相对稳定、逐年下降3个阶段;胶原酶的注射方式曾是研究重点,近些年研究热点集中于胶原酶的联合治疗。结论 胶原酶在老年或者难治性腰椎间盘突出症中仍具有研究价值,胶原酶与其他微创介入联合治疗是今后研究热点。     

盘内注射胶原酶溶解术治疗腰椎间盘突出症

作者报告采用盘内注射胶原酶溶解术治疗腰椎间盘突出症，自1994年来共治疗86例。注射采用俯卧位局部浸润麻醉并在电视X线（或B超）监控下进行。术后绝对卧床观察7～14天。由于该疗法可在电视X线或B超监控下就能顺利操作，且安全简便，疗效确切，作者认为该疗法也较适合在基层医院推广和应用。     

腰椎间盘突出症三种治疗方法的回顾性研究

目的 :对后路显微内窥镜下髓核摘除术 (MED组 )、后路开窗髓核摘除术 (Love组 )及胶原酶化学溶盘术 (CCNL组 )治疗腰椎间盘突出症的方法和疗效进行回顾性研究。方法 :采用统一的病例选择和疗效评定标准 ,对 2 37例患者 (其中MED组 87例 ,Love组 6 5例 ,CCNL组 85例 )进行分析 ,比较三组术后近、中期日本骨科协会 (JOA) 2 9分法评分及优良率 ,同时比较MED组和Love组病人围手术期有关情况。结果 :(1)MED组术后近、中期JOA评分及优良率高于Love组 ,但无统计学差异 ;(2 )CCNL组近、中期JOA评分及优良率均低于MED和Love组 ,差异显著 (P <0 .0 0 1) ;(3)术后中期与近期JOA评分比较 ,MED组和Love组有所提高 (P <0 .0 0 1) ,而CCNL组则略有下降 (P >0 .0 5 ) ;(4 )MED组在手术切口长度、术中出血量、术后引流量和卧床时间等方面均优于Love组 (P <0 .0 0 1)。结论 :在治疗腰椎间盘突出症的三种方法中 ,MED手术较Love法创伤更小 ,恢复更快 ,较CCNL术疗效更好。但CCNL术也有方法简单方便 ,基本无创的优点。     

Protease levels are significantly altered in pediatric burn wounds

Burn wounds contain high levels of protease activity due to the need to remodel the damaged extracellular matrix proteins. While necessary, excessive protease activity can lead to improper wound healing and is associated with increased contraction and fibrosis. No studies to date have investigated the expression changes of all the collagenases and elastases in burn wounds. The present study compares gene expression changes and changes in collagenase and elastase activity between burn wound eschar and normal skin in a pediatric population. Deidentified pediatric tissues were used for these experiments. Burn wound tissue was excised as part of normal standard care within a week from injury; normal skin was removed during elective plastic surgery procedures. RNA-sequencing was performed and significant results were confirmed with qRT-PCR. Activity assays showed a significant increase in both collagenase and elastase activity in the burn wound tissue compared to the normal skin. Western blotting and substrate zymography of tissue homogenates evaluated the results at the protein levels. Four elastases and three collagenases were determined to be significantly upregulated in the wound tissues by both RNA-sequencing and qRT-PCR. Cathepsin V was the only protease that was significantly downregulated. All but one metalloproteinase studied was significantly upregulated. None of the serine proteases were significantly altered in the wound tissues. In conclusion, matrix metalloproteinases appear to be the most highly elevated proteases after a pediatric burn wound injury, at least within the first 3–7 days. The data warrant further investigation into the effects of MMPs on burn wound healing.     

虫草多糖脂质体对大鼠肝纤维化胶原酶mRNA变化的影响

目的评价虫草多糖脂质体的抗肝纤维化作用．方法采用小剂量虫草多糖脂质体（虫草多糖量为１５ｍｇ／１００ｇ，隔日１次）治疗ＣＣｌ４所致雄性Ｗｉｓｔａｒ大鼠肝纤维化（ｎ＝１２）１０周．运用地高辛自由引物法标记的１７ｋｂ胶原酶探针行点渍印迹杂交检测大鼠肝组织中的胶原酶ｍＲＮＡ含量．结果小剂量虫草多糖脂质体使大鼠肝组织中胶原酶ｍＲＮＡ含量增高非常显著（灰度数字转换值，７９１５±２０２３ｖｓ３１３０±６９２，Ｐ＜００１）．结论虫草多糖脂质体通过增加肝组织胶原酶ｍＲＮＡ的表达，促使Ⅰ，Ⅲ型胶原降解，可能是其抗纤维化的主要机制之一．