Given the limited spontaneous repair that follows cartilage injury, demand is growing for tissue engi- neering approaches for cartilage regeneration. There are two major applications for tissue-engineered cartilage. O...Given the limited spontaneous repair that follows cartilage injury, demand is growing for tissue engi- neering approaches for cartilage regeneration. There are two major applications for tissue-engineered cartilage. One is in orthopedic surgery, in which the engineered cartilage is usually used to repair cartilage defects or loss in an articular joint or meniscus in order to restore the joint function. The other is for head and neck reconstruction, in which the engineered cartilage is usually applied to repair cartilage defects or loss in an auricle, trachea, nose, larynx, or eyelid. The challenges faced by the engineered car- tilage for one application are quite different from those faced by the engineered cartilage for the other application. As a result, the emphases of the engineering strategies to generate cartilage are usually quite different for each application. The statuses of preclinical animal investigations and of the clinical translation of engineered cartilage are also at different levels for each application. The aim of this review is to provide an opinion piece on the challenges, current developments, and future directions for cartilage engineering for both applications.展开更多
AIM To clone and identify the whole cDNA ofMXR7 gene and to find out its expression inhuman HCC,and normal tissues.METHODS The DNA primers were designed andsynthesized according to the whole cDNAsequence of MXR? gene....AIM To clone and identify the whole cDNA ofMXR7 gene and to find out its expression inhuman HCC,and normal tissues.METHODS The DNA primers were designed andsynthesized according to the whole cDNAsequence of MXR? gene.The cDNA of humanHCC was taken as the template while the cDNA ofMXR7 gene was synthesized by polymerasechain reaction（PCR）.Recombinant DNAconforming to reading frame was constructed byconnecting purified PCR product of the cDNA ofMXR? gene with expression vector pGEX-5X-1 offusion protein.The plasmid MXRT/pGEX-5X-1was identified by sequencing.Using <sup>32</sup>p labeledMXR? cDNA as probe,MXR7 mRNA expressionwas detected by Northern blot analysis in 12different human normal tissues,7 preoperativelyuntreated non-liver tumor tissues,30preoperatively untreated HCC,theparacancerous liver tissues and 12 normal livertissues samples.RESULTS Restriction enzyme and sequenceanalysis confirmed that the insertion sequence invector pGEX-5X-1 was the same as the cDNAsequence of MXR7 gene.Northern blot analysisshowed no expression of MXR? mRNA in 12 kindsof normal human tissues including liver,7 tumortissues in other sites and 12 normal livertissues,the frequencies of MXR7 mRNA expression in HCC and paracancerous livertissues were 76.6% and 13.3%,respectively.The frequency of MXR7 mRNA expression in HCCwithout elevation of serum AFP and in HCC【5cm was 90%（9/10）and 83.3%（5/6）,respectively.CONCLUSION MXR7 mRNA is highly expressedin human HCC,which is specific and occurs at anearly stage of HCC,suggesting MXR7 mRNA canbe a tumor biomarker for HCC.The detection ofMXR7 mRNA expression in the biopsied livertissue is helpful in discovering early subclinicalliver cancer in those with negative serum AFP.展开更多
背景:股骨头坏死出现新月征是病情进程的“分水岭”,修复和稳定骨-软骨界面对阻止病情继续进展和预防股骨头塌陷尤为重要。利用组织工程学同步修复、整合骨-软骨界面具有潜在优势。目的:综述探讨解决股骨头坏死软骨下分离的潜在适宜技...背景:股骨头坏死出现新月征是病情进程的“分水岭”,修复和稳定骨-软骨界面对阻止病情继续进展和预防股骨头塌陷尤为重要。利用组织工程学同步修复、整合骨-软骨界面具有潜在优势。目的:综述探讨解决股骨头坏死软骨下分离的潜在适宜技术。方法:检索1970年1月至2023年4月PubMed、Web of Science及中国知网、万方数据库中发表的相关文献,英文检索词:“Femoral head necrosis,Avascular necrosis of femoral head,Osteonecrosis of femoral head”等,中文检索词:“股骨头坏死,软骨下骨,软骨,软骨与软骨下骨整合”等,最终纳入114篇文献进行综述分析。结果与结论:①结构缺陷、缺血缺氧环境、炎症因素和应力集中可能造成股骨头坏死软骨下分离现象,软骨下骨分离会造成塌陷进展,并且可能与保髋手术失败相关,利用组织工程支架实现支架与骨-软骨界面的整合是治疗股骨头坏死软骨下分离的潜在方法之一。②目前的文献研究表明,多相、梯度支架和复合材料在促进骨、软骨细胞黏附与增殖,骨软骨基质的沉积方面均有提升,有助于支架与骨-软骨界面的整合,对治疗股骨头坏死软骨下分离有参考价值。③通过对支架表面进行修饰可以提高与界面整合的效率,但有各自不同的优缺点,提供不同环境的支架能够诱导同种间充质干细胞差异分化,有助于不同界面之间的整合。④未来有望应用于股骨头坏死软骨下分离的支架应为复合材料,具有梯度化和差异化的仿生结构,通过表面修饰和干细胞加载促进骨-软骨界面与支架的整合以实现治疗目的,但仍需进一步研究验证,而支架的降解速率与修复进度同步和不同界面之间的稳定性是未来需要解决的主要问题。展开更多
When conducting a literature review,medical authors typically search for relevant keywords in bibliographic databases or on search engines like Google.After selecting the most pertinent article based on the title’s r...When conducting a literature review,medical authors typically search for relevant keywords in bibliographic databases or on search engines like Google.After selecting the most pertinent article based on the title’s relevance and the abstract’s content,they download or purchase the article and cite it in their manuscript.Three major elements influence whether an article will be cited in future manuscripts:the keywords,the title,and the abstract.This indicates that these elements are the“key dissemination tools”for research papers.If these three elements are not determined judiciously by authors,it may adversely affect the manuscript’s retrievability,readability,and citation index,which can negatively impact both the author and the journal.In this article,we share our informed perspective on writing strategies to enhance the searchability and citation of medical articles.These strategies are adopted from the principles of search engine optimization,but they do not aim to cheat or manipulate the search engine.Instead,they adopt a reader-centric content writing methodology that targets well-researched keywords to the readers who are searching for them.Reputable journals,such as Nature and the British Medical Journal,emphasize“online searchability”in their author guidelines.We hope that this article will encourage medical authors to approach manuscript drafting from the perspective of“looking inside-out.”In other words,they should not only draft manuscripts around what they want to convey to fellow researchers but also integrate what the readers want to discover.It is a call-to-action to better understand and engage search engine algorithms,so they yield information in a desired and self-learning manner because the“Cloud”is the new stakeholder.展开更多
背景:关于股骨头坏死的发病机制国内外学者提出了各种学说:血运障碍、脂质代谢紊乱、骨内压增高、骨细胞凋亡、基因多态性、免疫因素等,但其具体发病机制仍不明确。目的:就股骨头坏死的发病机制研究进展作一综述,以期为研究股骨头坏死...背景:关于股骨头坏死的发病机制国内外学者提出了各种学说:血运障碍、脂质代谢紊乱、骨内压增高、骨细胞凋亡、基因多态性、免疫因素等,但其具体发病机制仍不明确。目的:就股骨头坏死的发病机制研究进展作一综述,以期为研究股骨头坏死的学者提供线索。方法:以"femoral head necrosis,osteonecrosis of femoral head,pathogenesis,mechanism"检索词在Pubmed、Embase、Medline等数据库检索1985至2017年的文献;以"股骨头坏死"、"发病机制"为检索词检索中国知网、万方及维普1985至2017年的文献,最终纳入39篇文献进行回顾性分析。结果与结论:股骨头坏死是多种因素共同作用导致的复杂疾病,生物力学因素在其发生发展过程中发挥重要作用。股骨头内部力学性能的减退或者各种危险因素导致的外界应力与股骨头内部结构不协调,引起内部骨小梁的微骨折,应力集中,反复破坏与修复,当破坏速度超过修复速度,股骨头最终发生塌陷。大部分股骨头坏死病例均为散发病例,但也有研究报道家族中多名成员患有特发性股骨头坏死,呈家族聚集性,股骨头坏死可能和遗传因素有关联。展开更多
背景:临床研究表明骨细胞自噬参与了激素性股骨头坏死的病理过程,并与细胞凋亡关系密切。目的:通过对细胞自噬与细胞凋亡及骨细胞的相互作用关系,总结细胞自噬在激素性股骨头缺血坏死发病机制中的研究进展。方法:由第一作者应用计算机...背景:临床研究表明骨细胞自噬参与了激素性股骨头坏死的病理过程,并与细胞凋亡关系密切。目的:通过对细胞自噬与细胞凋亡及骨细胞的相互作用关系,总结细胞自噬在激素性股骨头缺血坏死发病机制中的研究进展。方法:由第一作者应用计算机检索应用计算机检索PubMed数据库,embase数据库,CNKI数据库中从1996年10月到2016年10月出版的文献,检索词分别为"steroid;necrosis of the femoral head;cell apoptosis;cell autophagy;osteocyte"和"糖皮质激素;股骨头坏死;骨细胞;细胞凋亡;细胞自噬"。选择激素性股骨头坏死与细胞自噬的文章,排除重复及较陈旧的文献及Meta分析。结果与结论:哺乳动物雷帕霉素靶蛋白、Beclin-1、微管相关蛋白1轻链3及骨形成蛋白、叉头框蛋白和转录基因家族和转录因子4等与细胞自噬关系密切;细胞自噬与骨细胞的相互作用与激素剂量密切相关,低剂量激素作用下,细胞自噬表现为保护作用,而随着剂量的增多,出现了大量细胞凋亡现象,同时也出现骨量减少,骨易碎性增加的现象,而细胞自噬与骨量维持、细胞凋亡的具体关系现在仍存在争论,需要进一步通过合理的实验设计去研究。展开更多
文摘Given the limited spontaneous repair that follows cartilage injury, demand is growing for tissue engi- neering approaches for cartilage regeneration. There are two major applications for tissue-engineered cartilage. One is in orthopedic surgery, in which the engineered cartilage is usually used to repair cartilage defects or loss in an articular joint or meniscus in order to restore the joint function. The other is for head and neck reconstruction, in which the engineered cartilage is usually applied to repair cartilage defects or loss in an auricle, trachea, nose, larynx, or eyelid. The challenges faced by the engineered car- tilage for one application are quite different from those faced by the engineered cartilage for the other application. As a result, the emphases of the engineering strategies to generate cartilage are usually quite different for each application. The statuses of preclinical animal investigations and of the clinical translation of engineered cartilage are also at different levels for each application. The aim of this review is to provide an opinion piece on the challenges, current developments, and future directions for cartilage engineering for both applications.
基金the National Natural Science Foundation of China,No.39770379the National Basic Research Project("973")SUGEN,USA.
文摘AIM To clone and identify the whole cDNA ofMXR7 gene and to find out its expression inhuman HCC,and normal tissues.METHODS The DNA primers were designed andsynthesized according to the whole cDNAsequence of MXR? gene.The cDNA of humanHCC was taken as the template while the cDNA ofMXR7 gene was synthesized by polymerasechain reaction（PCR）.Recombinant DNAconforming to reading frame was constructed byconnecting purified PCR product of the cDNA ofMXR? gene with expression vector pGEX-5X-1 offusion protein.The plasmid MXRT/pGEX-5X-1was identified by sequencing.Using <sup>32</sup>p labeledMXR? cDNA as probe,MXR7 mRNA expressionwas detected by Northern blot analysis in 12different human normal tissues,7 preoperativelyuntreated non-liver tumor tissues,30preoperatively untreated HCC,theparacancerous liver tissues and 12 normal livertissues samples.RESULTS Restriction enzyme and sequenceanalysis confirmed that the insertion sequence invector pGEX-5X-1 was the same as the cDNAsequence of MXR7 gene.Northern blot analysisshowed no expression of MXR? mRNA in 12 kindsof normal human tissues including liver,7 tumortissues in other sites and 12 normal livertissues,the frequencies of MXR7 mRNA expression in HCC and paracancerous livertissues were 76.6% and 13.3%,respectively.The frequency of MXR7 mRNA expression in HCCwithout elevation of serum AFP and in HCC【5cm was 90%（9/10）and 83.3%（5/6）,respectively.CONCLUSION MXR7 mRNA is highly expressedin human HCC,which is specific and occurs at anearly stage of HCC,suggesting MXR7 mRNA canbe a tumor biomarker for HCC.The detection ofMXR7 mRNA expression in the biopsied livertissue is helpful in discovering early subclinicalliver cancer in those with negative serum AFP.
文摘背景:股骨头坏死出现新月征是病情进程的“分水岭”,修复和稳定骨-软骨界面对阻止病情继续进展和预防股骨头塌陷尤为重要。利用组织工程学同步修复、整合骨-软骨界面具有潜在优势。目的:综述探讨解决股骨头坏死软骨下分离的潜在适宜技术。方法:检索1970年1月至2023年4月PubMed、Web of Science及中国知网、万方数据库中发表的相关文献,英文检索词:“Femoral head necrosis,Avascular necrosis of femoral head,Osteonecrosis of femoral head”等,中文检索词:“股骨头坏死,软骨下骨,软骨,软骨与软骨下骨整合”等,最终纳入114篇文献进行综述分析。结果与结论:①结构缺陷、缺血缺氧环境、炎症因素和应力集中可能造成股骨头坏死软骨下分离现象,软骨下骨分离会造成塌陷进展,并且可能与保髋手术失败相关,利用组织工程支架实现支架与骨-软骨界面的整合是治疗股骨头坏死软骨下分离的潜在方法之一。②目前的文献研究表明,多相、梯度支架和复合材料在促进骨、软骨细胞黏附与增殖,骨软骨基质的沉积方面均有提升,有助于支架与骨-软骨界面的整合,对治疗股骨头坏死软骨下分离有参考价值。③通过对支架表面进行修饰可以提高与界面整合的效率,但有各自不同的优缺点,提供不同环境的支架能够诱导同种间充质干细胞差异分化,有助于不同界面之间的整合。④未来有望应用于股骨头坏死软骨下分离的支架应为复合材料,具有梯度化和差异化的仿生结构,通过表面修饰和干细胞加载促进骨-软骨界面与支架的整合以实现治疗目的,但仍需进一步研究验证,而支架的降解速率与修复进度同步和不同界面之间的稳定性是未来需要解决的主要问题。
文摘When conducting a literature review,medical authors typically search for relevant keywords in bibliographic databases or on search engines like Google.After selecting the most pertinent article based on the title’s relevance and the abstract’s content,they download or purchase the article and cite it in their manuscript.Three major elements influence whether an article will be cited in future manuscripts:the keywords,the title,and the abstract.This indicates that these elements are the“key dissemination tools”for research papers.If these three elements are not determined judiciously by authors,it may adversely affect the manuscript’s retrievability,readability,and citation index,which can negatively impact both the author and the journal.In this article,we share our informed perspective on writing strategies to enhance the searchability and citation of medical articles.These strategies are adopted from the principles of search engine optimization,but they do not aim to cheat or manipulate the search engine.Instead,they adopt a reader-centric content writing methodology that targets well-researched keywords to the readers who are searching for them.Reputable journals,such as Nature and the British Medical Journal,emphasize“online searchability”in their author guidelines.We hope that this article will encourage medical authors to approach manuscript drafting from the perspective of“looking inside-out.”In other words,they should not only draft manuscripts around what they want to convey to fellow researchers but also integrate what the readers want to discover.It is a call-to-action to better understand and engage search engine algorithms,so they yield information in a desired and self-learning manner because the“Cloud”is the new stakeholder.
文摘背景:关于股骨头坏死的发病机制国内外学者提出了各种学说:血运障碍、脂质代谢紊乱、骨内压增高、骨细胞凋亡、基因多态性、免疫因素等,但其具体发病机制仍不明确。目的:就股骨头坏死的发病机制研究进展作一综述,以期为研究股骨头坏死的学者提供线索。方法:以"femoral head necrosis,osteonecrosis of femoral head,pathogenesis,mechanism"检索词在Pubmed、Embase、Medline等数据库检索1985至2017年的文献;以"股骨头坏死"、"发病机制"为检索词检索中国知网、万方及维普1985至2017年的文献,最终纳入39篇文献进行回顾性分析。结果与结论:股骨头坏死是多种因素共同作用导致的复杂疾病,生物力学因素在其发生发展过程中发挥重要作用。股骨头内部力学性能的减退或者各种危险因素导致的外界应力与股骨头内部结构不协调,引起内部骨小梁的微骨折,应力集中,反复破坏与修复,当破坏速度超过修复速度,股骨头最终发生塌陷。大部分股骨头坏死病例均为散发病例,但也有研究报道家族中多名成员患有特发性股骨头坏死,呈家族聚集性,股骨头坏死可能和遗传因素有关联。
文摘背景:临床研究表明骨细胞自噬参与了激素性股骨头坏死的病理过程,并与细胞凋亡关系密切。目的:通过对细胞自噬与细胞凋亡及骨细胞的相互作用关系,总结细胞自噬在激素性股骨头缺血坏死发病机制中的研究进展。方法:由第一作者应用计算机检索应用计算机检索PubMed数据库,embase数据库,CNKI数据库中从1996年10月到2016年10月出版的文献,检索词分别为"steroid;necrosis of the femoral head;cell apoptosis;cell autophagy;osteocyte"和"糖皮质激素;股骨头坏死;骨细胞;细胞凋亡;细胞自噬"。选择激素性股骨头坏死与细胞自噬的文章,排除重复及较陈旧的文献及Meta分析。结果与结论:哺乳动物雷帕霉素靶蛋白、Beclin-1、微管相关蛋白1轻链3及骨形成蛋白、叉头框蛋白和转录基因家族和转录因子4等与细胞自噬关系密切;细胞自噬与骨细胞的相互作用与激素剂量密切相关,低剂量激素作用下,细胞自噬表现为保护作用,而随着剂量的增多,出现了大量细胞凋亡现象,同时也出现骨量减少,骨易碎性增加的现象,而细胞自噬与骨量维持、细胞凋亡的具体关系现在仍存在争论,需要进一步通过合理的实验设计去研究。
