科学松鼠会 发表于 2011-03-07 14:56 作者:赵承渊 这是一个非常有趣的病例(相关报道已见诸报端)。 一名男子在醉酒状态下不慎将一枚由曲别针改制的缝衣针扎入胸部,扎入后没有特别的不适并继续进行体力劳动。2个月后才在家人的催促下到当地医院检查,X光照相显示针位于纵隔内。当即决定开胸取针,打开胸腔后发现针已经扎入了心脏,位于室间隔上,当地医院觉得病情复杂棘手,建议患者转诊北京某著名心血管病医院。该医院读胸片后确认针处于室间隔,拟再次开胸手术。手术前一天进行胸部CT,却怎么也找不到针的踪影……多学科的医生们反复读片试图寻觅这枚行踪诡异的针,却还是摸不着头脑——一枚扎进心脏室间隔的针就这样在众目睽睽之下消失了。无奈之下大家决定对患者进行全身透视,在X光的帮助下东寻西找,最后竟在患者的右大腿内侧找到了这枚针。取出后发现针大约5cm长,表面已生锈,针尖仍很锐利。 这枚山寨缝衣针从心脏到大腿的奇特旅程在医生眼中其实并无多少新奇之处。由于心脏是血液循环的动力枢纽,因此理论上来说,心脏内的异物可以被血流带到身体的任何地方,这名患者异物最终定居在大腿,也没什么值得大惊小怪。当发现扎在室间隔上的针不见踪影时,医生们更担心的其实是这枚针“旅程”中可能发生的事情:由于针是锐器,随血流运动过程中极易刺破重要血管造成不可挽回的大出血,或随血流流到某些重要脏器内发生栓塞,上述情况会在短时间内危及生命或造成残疾。这名男子不但躲过了第二次开胸,而且针在旅行过程中没有造成任何额外的麻烦,5cm的针相对较长不易拐弯,没有进入口径较小的动脉血管,也没有造成重要脏器的栓塞,堪称幸运!患者自针扎入胸膛到赴医院就医,历时2个月之久,中间继续进行体力劳动竟无任何不适,且异物在体内没有造成严重感染,令人匪夷所思。醉酒后不慎将针扎进胸膛虽属一时大意造成不幸,但之后发生的一切则不得不让人感慨运气实在是太眷顾他了。 相比而言,美国一位类似患者的情况就没有这么顺利了。今年年初著名的《新英格兰医学杂志》报道了一名35岁的木匠,由于反复发作寒战高烧近半个月被送至麻省总医院。这名木匠经历了包括全血培养,头部、胸部,腹部CT、MRI,心脏CT、超声心动图、血管造影和气管镜在内的全身检查,最终才确定患者的严重感染起源于左心房内的一块异物。该异物类似鬃毛,呈现黑色金属光泽,长约2.7cm,推测可能为木匠常用的某种工具。该木匠在工作中可能无意中吞下或吸入了该物(很多人干活时喜欢把即将用到的工具叼在嘴里),由于该异物经过口腔,口腔内大量的细菌污染了这枚异物,异物吸入肺内,突破支气管扎进了左心房。随后细菌在血液中大量繁殖并播散到全身,造成全身多处部位脓肿:脑部多发脓肿,皮肤脓肿。医生们不得不开胸使心脏停跳,然后才小心翼翼地拔出了这枚异物,细菌感染使得这枚异物表面布满了赘生物。取出异物后3个月,患者才康复并重新开始工作。 通常而言,心脏异物的来源可分为两种:医源性与非医源性。而非医源性心脏异物又可通过两种途径进入心脏:一种是经过皮肤,如本文开头的那位“幸运”的男子一样;另一种则是经过内脏,如美国的这位木匠。当然木匠的这种吸入途径也是十分罕见的,更多见的则是经过吞咽,异物通过胃肠道进入腔静脉,再随着血液流进右心房和右心室。因此,心脏异物绝大多数发生在右心,且引发感染的也常常是多见于胃肠道的细菌。某些情况下,鱼骨或鸡骨等锐利小异物可以穿透食管直接扎入纵隔,造成发烧,剧烈背痛,胸痛,呼吸困难甚至休克。因此当我们卡到鱼刺或者鸡骨的时候切莫粗心大意强咽下去,有时可能造成严重后果。 其实对我们来说,肉眼可见的心脏异物毕竟是较少见的情况。而肉眼看不见的细菌往往才是疾病的罪魁祸首。前面已经提到,心脏异物可以通过血液循环到达身体的各个部位,细菌也能进行类似的长途旅行。美国那位木匠的全身感染,正是细菌周游全身四处闯祸的绝好例子。虽然我们机体有强大的免疫系统时刻监视着致病菌的动向,但当我们免疫功能下降,或致病菌的侵袭力很强、数量很多时,感染就会在全身播散。化脓性细菌侵入心脏,往往会附着在心脏瓣膜并形成赘生物,称为“感染性心内膜炎”。赘生物不断脱落又产生,在此过程中大量的细菌便随着血液循环到达全身各处,表现为多系统多部位的脓肿,如肝脓肿,脑脓肿,肺脓肿,脾脓肿等等。避免致病菌大举入侵造成感染性心内膜炎的方法,一是要锻炼身体提高免疫力;另一方面是在进行某些高危医疗操作(如某些牙科操作)时预防性使用抗生素,事实证明,这是行之有效的方法。 除了异物、细菌等不速之客,心脏自身也会制造出一些麻烦家伙来。在某些情况下,特别是当心脏跳动的节律发生改变、心脏瓣膜出现问题时,血液会在心房内不正常地凝集并附着在心脏内壁形成附壁血栓。当这种附壁血栓脱落并随着血流四处游荡时,便可能造成脑梗塞等不良后果。医生们常常会让房颤患者服用抗凝药物,正是出于预防附壁血栓的考虑。其他更少见的情况还包括一些原发于心脏的肿瘤,转移至心脏的肿瘤等等。从缝衣针等心脏异物到源自心脏的各种疾病,围绕心脏的医学探索已形成了一个专门学科:心脏病学。 参考文献 Case 1-2011 — A 35-Year-Old Man with Fever, Bacteremia, and a Mass in the Left Atrium.Adolf W. Karchmer, M.D., Thomas E. MacGillivray, M.D., Terrance T. Healey, M.D., and James R. Stone, M.D., Ph.D. N Engl J Med 2011; 364:158-166. 您也可能喜欢: 不再缺心眼——初生小鼠心脏可再生 马拉松长跑会损伤心脏吗? 当科普的科幻尝起来是文学的 “心脏搭桥”的故事 我国心脏移植术后存活最长者病逝 无觅
最新研究报道 http://news.xinhuanet.com/english2010/health/2010-03/31/c_13231861.htm BEIJING, March 31 (Xinhuanet) -- German researchers recently found having a moderate amount of chocolate may be good for blood-pressure control and therefore better protect the heart, according to a report published on European Heart Journal. Researchers in German Institute of Human Nutrition conducted a study on more than 19,300 people. Over a decade's study, they discovered that those who ate the most amount of chocolate, that is, an average of 7.5 grams a day, had lower blood pressure and a 39 percent lower risk of having a heart attack or stroke compared to those who had an average of 1.7 grams a day, the least among the subjects. http://www.gopubmed.org/web/gopubmed/4?WEB01644h5xtag2beI7I5I00f01000j10040001rl Chocolate and heartand blood pressure 129 documents semantically analyzed 1 2 Top Years Publications 2006 16 2008 13 2009 12 2000 11 2007 10 2001 7 2004 5 1999 5 2010 4 1997 4 1989 4 2003 3 1996 3 2005 2 2002 2 1994 2 1993 2 1991 2 1988 2 1983 2 1 2 1 2 Top Countries Publications USA 34 Germany 6 United Kingdom 6 Japan 5 Australia 5 Italy 4 Switzerland 4 Sweden 3 Spain 3 Canada 3 China 3 Brazil 2 Ireland 2 Turkey 2 Greece 2 Netherlands 2 Taiwan 2 Iran 1 Denmark 1 Nigeria 1 1 2 1 2 3 4 Top Cities Publications Davis 6 Boston 4 Leipzig 2 Stockholm 2 Dublin 2 Milan 2 Zrich 2 London 2 Athens 2 Washington 2 San Francisco 2 Rochester, MN, USA 2 Seattle 2 Porto Alegre 1 Barcelona 1 Afyonkarahisar 1 Newcastle upon Tyne 1 Messina 1 Tokyo 1 Wollongong 1 1 2 3 4 1 2 3 4 5 Top Journals Publications J Clin Microbiol 11 Am J Clin Nutr 8 Am J Hypertens 3 Int J Cardiol 3 Mol Nutr Food Res 3 Am J Cardiol 3 J Cardiovasc Pharm 3 Eur J Clin Nutr 2 Circulation 2 Heart 2 Crit Care Nurse 2 Cardiovasc Res 2 Nutr Rev 2 J Am Diet Assoc 2 J Med Microbiol 2 West Afr J Med 2 J Nutr Biochem 2 Zentralbl Bakteriol Mikrobiol Hyg 2 Expert Rev Cardiovasc Ther 1 Nutr Res Rev 1 1 2 3 4 5 1 2 3 ... 26 Top Authors Publications Keen C 4 Corti R 3 Roberts G 3 Grivetti L 2 Hermann F 2 Sudano I 2 Spieker L 2 Hermann M 2 Lscher T 2 Ruschitzka F 2 Nll G 2 Stefanadis C 2 Vlachopoulos C 2 Alexopoulos N 2 Aznaouridis K 2 Schmitz H 2 Dyerberg J 2 Stender S 2 Cockerill F 2 Vetter E 2 1 2 3 ... 26 1 2 3 ... 66 Top Terms Publications Cacao 121 Humans 102 Adult 40 Heart Diseases 37 Patients 33 Coronary Disease 26 Flavonoids 26 Middle Aged 26 Animals 23 Evaluation Studies as Topic 22 Blood Pressure 21 Culture Media 21 Pressure 20 Eating 20 Cardiovascular Diseases 20 Aged 20 Beverages 19 Incubators 19 Arteries 17 Oxides 17 1 2 3 ... 66
http://www.gopubmed.org/web/gopubmed/1?WEB0t1j2zq3c616nI1mI1I00f01000j10040001rl 4,305 documents semantically analyzed 1 2 3 Top Years Publications 2008 563 2007 555 2006 443 2005 431 2009 384 2004 366 2003 280 2002 187 2000 109 2001 108 1999 78 1997 74 1995 71 1998 70 1996 59 1994 51 1993 34 1992 28 1989 24 1982 23 1 2 3 1 2 3 Top Countries Publications USA 1,096 Germany 286 Japan 254 China 250 Canada 131 Italy 113 United Kingdom 110 France 110 Netherlands 102 Israel 38 Australia 35 Switzerland 33 Belgium 29 India 27 Spain 26 Austria 25 Sweden 25 Taiwan 24 Poland 17 Brazil 17 1 2 3 1 2 3 ... 22 Top Cities Publications Boston 87 New York 63 Beijing 60 London 56 Toronto 55 Paris 54 Houston 51 San Diego 45 Tokyo 41 Stanford 40 San Francisco 39 Cologne 38 Utrecht 34 Baltimore 33 Philadelphia 33 Cincinnati 32 Kyoto 30 Los Angeles 27 Montreal 26 Seattle 25 1 2 3 ... 22 1 2 3 ... 40 Top Journals Publications Circ Res 124 J Mol Cell Cardiol 120 Circulation 104 Am J Physiol-heart C 97 Cardiovasc Res 87 Stem Cells 79 J Biol Chem 62 Biochem Bioph Res Co 55 Exp Cell Res 50 J Am Coll Cardiol 37 P Natl Acad Sci Usa 37 Stem Cells Dev 34 J Cell Biol 34 Dev Biol 33 Nat Clin Pract Cardiovasc Med 32 Faseb J 30 Int J Cardiol 29 Cell Transplant 28 Development 27 J Clin Invest 27 1 2 3 ... 40 1 2 3 ... 531 Top Terms Publications Myocardium 2,894 Animals 2,874 Myocytes, Cardiac 1,997 Fibroblasts 1,624 Humans 1,502 stem cell differentiation 1,481 stem cell development 1,472 Tissues 1,273 Mice 1,268 Proteins 1,228 Cells, Cultured 1,193 Cell Differentiation 1,089 Rats 1,056 Myocardial Infarction 1,022 Stem Cells 995 Muscle Cells 963 Adult 926 Genes 925 Muscles 864 Infarction 860 1 2 3 ... 531 1 2 3 ... 909 Top Authors Publications Hescheler J 47 Anversa P 41 Kajstura J 38 Leri A 34 Menasche P 29 Pucat M 27 Mummery C 26 Weber K 25 Fleischmann B 24 Nadal-Ginard B 23 Fukuda K 21 Gepstein L 21 Murry C 20 Lijnen P 20 Robbins R 19 Haider H 19 Wobus A 19 Chien K 18 Field L 18 Torella D 17 1 2 3 ... 909 http://www.sciencenet.cn/htmlpaper/20091022134402837577.shtm 用心脏干细胞育出心脏肌肉组织 美国研究人员说,他们成功地利用心脏干细胞在实验室中培育出心脏肌肉组织,这将为人类心脏病治疗带来突破。 这一研究成果发表在最近的《科学》杂志网络版上。 最新突破 尽管现代医学已经相当发达,但医生仍然找不到简单、快捷的方法治疗因心脏病发作导致的心脏组织破损。 研究领头人、哈佛大学干细胞研究所的肯尼思建介绍,美国科学家两个月前刚刚发现心脏干细胞,这为他和研究人员人工制造心脏肌肉组织提供可能。 建说,研究人员把细胞置于一层薄薄的高分子膜上,让它们成环形排列。这些细胞会自发重新组合,最后形成一片心脏组织,这块组织的形状则由供细胞繁衍的空间决定。 我们有纯净的干细胞,它们可以扩张,可以成为功能健全的肌肉组织,路透社引述建的话报道,这为治疗心脏病而制造心脏零件提供良好开端。 补丁原理 研究人员为心脏干细胞疗法修复心脏设想了两个途径。 其一是用一层心室肌肉细胞覆盖心脏破损区域,让它们逐渐生长成为能正常工作的心脏组织;其二是把细胞注射进破损区域,然后让它们自行生长。 建说,他计划一年内在不同动物身上进行这类试验,并预计这种技术可以在五年内应用于临床。 研究人员认为,这项成果让人类朝心脏干细胞疗法迈进一大步,建则把这种心脏修复疗法形象比喻为给心脏贴创可贴。 建说,在这项技术真正用于临床之前,研究人员还有几大难题需要解决,如何为新肌肉组织供血便是其中之一。 病患福音 干细胞是一种具有自我复制能力的多潜能细胞,在一定条件下可以分化成多种功能细胞。它们在实验室里繁衍迅速并且拥有很长寿命,是科研人员眼里的利器。 不过,洛杉矶心脏研究所主任爱德华多马尔万却认为,建所领导的研究临床意义有限,五年内应用于临床更是过分乐观。 他说,这类试验通常先在实验室进行,然后使用人体细胞在小动物身上试验,接着是猪等稍大型动物。因此,十年内能应用于临床就已经是巨大进步。(来源:新华网 林琳) 更多阅读 路透社相关报道(英文) 《科学》发表论文摘要(英文) http://www.reuters.com/article/scienceNews/idUSTRE59E5GP20091015 Study finds potential key to growing heart cells Thu Oct 15, 2009 3:08pm EDT WASHINGTON (Reuters) - Researchers looking for ways to turn stem cells into the types of heart cells they want said on Thursday they had found the key to making one important type in mice. They found the cells that give rise to the muscles of the ventricles -- the chambers that pump blood out of the heart -- in mice and said they will try to use this information to turn ordinary skin or blood cells into this important heart tissue. These so-called progenitor cells, described in a report in the journal Science, should also lead to better ways to study heart disease and to test drugs, the researchers said. This is the beginning of making heart parts for heart disease, said Kenneth Chien of the Harvard Stem Cell Institute in Massachusetts. We have the pure cells; they can be expanded, and they can make fully functional strip of muscle. Stem cells are the body's master cells, giving rise to the other, differentiated cells and tissues in the body. They multiply wildly in the lab and live almost forever, which makes them a powerful tool. When directed correctly, these cells can be made to form heart tissue, bone tissue, blood or other cells. But as they differentiate into these tissues, they lose their immortality and ability to proliferate. So scientists want to get from patients embryonic stem cells, or cells that resemble them called induced pluripotent stem cells, grow them in the lab and then use them for research and medical treatments. Being identical or close genetic matches, they would be easy to transplant back into patients. Chien's team genetically engineered mice that had fluorescent tags in their heart cells that made the right ventricle glow red. They could then find and isolate progenitor cells in mouse embryos that exclusively gave rise to ventricular muscle -- one of several types of muscle cell in the heart. That's the type of muscle in the heart we're trying to regenerate, Chien said in a statement. They used these cells to make batches of tissue that beat as a heart cell should. Because the hearts of mammals are all very similar, it should now be possible to find the human versions of these cells for study, they said. http://www.sciencemag.org/cgi/content/abstract/sci;326/5951/426?maxtoshow=HITS=10hits=10RESULTFORMAT=fulltext=Kenneth+Chien+searchid=1FIRSTINDEX=0sortspec=dateresourcetype=HWCIT Science 16 October 2009: Vol. 326. no. 5951, pp. 426 - 429 DOI: 10.1126/science.1177350 Reports Generation of Functional Ventricular Heart Muscle from Mouse Ventricular Progenitor Cells Ibrahim J. Domian, 1 ,2 ,* Murali Chiravuri, 1 ,* Peter van der Meer, 1 ,3 ,* Adam W. Feinberg, 4 Xi Shi, 1 Ying Shao, 1 Sean M. Wu, 1 ,2 Kevin Kit Parker, 2 ,4 ,5 Kenneth R. Chien 1 ,2 ,6 , The mammalian heart is formed from distinct sets of first and second heart field (FHF and SHF, respectively) progenitors. Although multipotent progenitors have previously been shown to give rise to cardiomyocytes, smooth muscle, and endothelial cells, the mechanism governing the generation of large numbers of differentiated progeny remains poorly understood. We have employed a two-colored fluorescent reporter system to isolate FHF and SHF progenitors from developing mouse embryos and embryonic stem cells. Genome-wide profiling of coding and noncoding transcripts revealed distinct molecular signatures of these progenitor populations. We further identify a committed ventricular progenitor cell in the Islet 1 lineage that is capable of limited in vitro expansion, differentiation, and assembly into functional ventricular muscle tissue, representing a combination of tissue engineering and stem cell biology. 1 Cardiovascular Research Center, Massachusetts General Hospital, Charles River Plaza, CPZN 3200, 185 Cambridge Street, Boston, MA 021142790, USA. 2 Harvard Stem Cell Institute, Cambridge, MA 02138, USA. 3 Department of Cardiology, University Medical Center Groningen, Hanzeplein 1, 9700 RB Groningen, Netherlands. 4 Disease Biophysics Group, School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA. 5 The Wyss Institue for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA. 6 Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA. * These authors contributed equally to this work. To whom correspondence should be addressed. E-mail: krchien@partners.org