近日,，來(lái)自麥吉爾大學(xué)的研究者在心臟肌肉組織的結(jié)構(gòu)上提出了新的見解，為心臟疾病的研究以及人工心臟的研究提供了新的線索,，相關(guān)研究成果刊登在了國(guó)際雜志PNAS上,。研究者表示,，心臟肌纖維一般排布在心臟的特殊極小曲面（一般的螺旋體）上,。研究者的研究增加了我們對(duì)心臟肌纖維尺寸特點(diǎn)以及其功能的理解。
數(shù)十年來(lái),，外科醫(yī)生和解剖學(xué)家已經(jīng)清楚地解析了心臟肌肉纖維的幾何學(xué)特征,，而且知道肌肉細(xì)胞可以對(duì)齊形成單環(huán)，并且卷繞形成心室,。但是這些分析僅僅是在單一纖維的水平上進(jìn)行的,。部分是因?yàn)閭鹘y(tǒng)的技術(shù)限制，研究者并沒有對(duì)一組肌纖維進(jìn)行深入的研究,。
麥吉爾大學(xué)的研究者和荷蘭以及美國(guó)的研究者共同努力,，將磁共振成像技術(shù)和計(jì)算機(jī)模型設(shè)計(jì)技術(shù)充分結(jié)合，揭示了纖維束是共同彎曲在一起的,，研究者同時(shí)檢測(cè)了小鼠,、人類和狗的心臟組織結(jié)構(gòu)，發(fā)現(xiàn)其具有相同的模式,。
研究者Siddiqi表示,，你可以將其想象為一撮頭發(fā)取代了單一的一根頭發(fā)絲兒，我們同時(shí)也發(fā)現(xiàn),，肌纖維以螺旋的形式來(lái)彎曲扭轉(zhuǎn),，而且在各個(gè)物種都是這樣的。我們的研究可以為心臟壁損傷修復(fù)提供一些平臺(tái)和支持,。肌肉組織再生是生物工程的一個(gè)主要領(lǐng)域,，在這個(gè)領(lǐng)域內(nèi)更多的發(fā)展涉及到骨骼肌組織，比如胳膊和腿,，這些肌肉組織都是以不同的線性結(jié)構(gòu)來(lái)排列的,。（生物谷Bioon.com）
編譯自：http://www.sciencedaily.com/releases/2012/05/120528154945.htm
doi:10.1073/pnas.1120785109
PMC:
PMID:
Heart wall myofibers are arranged in minimal surfaces to optimize organ function
Peter Savadjieva, Gustav J. Strijkersb, Adrianus J. Bakermansb, Emmanuel Piuzec, Steven W. Zuckerd, and Kaleem Siddiqic,1
Heart wall myofibers wind as helices around the ventricles, strengthening them in a manner analogous to the reinforcement of concrete cylindrical columns by spiral steel cables [Richart FE, et al. (1929) Univ of Illinois, Eng Exp Stn Bull 190]. A multitude of such fibers, arranged smoothly and regularly, contract and relax as an integrated functional unit as the heart beats. To orchestrate this motion, fiber tangling must be avoided and pumping should be efficient. Current models of myofiber orientation across the heart wall suggest groupings into sheets or bands, but the precise geometry of bundles of myofibers is unknown. Here we show that this arrangement takes the form of a special minimal surface, the generalized helicoid [Blair DE, Vanstone JR (1978) Minimal Submanifolds and Geodesics 13–16], closing the gap between individual myofibers and their collective wall structure. The model holds across species, with a smooth variation in its three curvature parameters within the myocardial wall providing tight fits to diffusion magnetic resonance images from the rat, the dog, and the human. Mathematically it explains how myofibers are bundled in the heart wall while economizing fiber length and optimizing ventricular ejection volume as they contract. The generalized helicoid provides a unique foundation for analyzing the fibrous composite of the heart wall and should therefore find applications in heart tissue engineering and in the study of heart muscle diseases.
