Sakhnini Lama, Dairi Maheen, Manaa Hacene
Physics Department, College of Science, University of Bahrain, P. O. Box 32038, Sakhir, Kingdom of Bahrain.
J Biophotonics. 2008 Aug;1(3):238-44. doi: 10.1002/jbio.200810002.
In this study we report on magnetic orientation of human sperms. Samples were taken from 17 donors. Normal human sperms became oriented with their long axis perpendicular to the magnetic field (1 T maximum). Total orientation was achieved with magnetic field of about 1 T, while for abnormal sperms the magnetic behavior was different. The dependence of the measured degree of orientation on the intensity of the magnetic field was in good agreement with the theoretical equation for the magnetic orientation of diamagnetic substances. As a result of a numerical analysis based on the equation, the anisotropic diamagnetic susceptibility of normal sperm was found to be Delta(chi) = 8 x 10(-20) J/T(2). The degree of orientation was influenced by the alterations in the shape of the head, body or the tail. It has been suggested that the DNA in the sperm head retain the strong magnetic anisotropy to counterbalance the magnetic anisotropy retained by flagellum microtubules. Recent studies demonstrated a well-defined nuclear architecture in human sperm nucleus, where the head morphology has significant correlation with sperm chromatin structure assay SCSA. Then, as the methods to evaluate SCSA can be difficult and expensive our simple magnetic orientation technique can be an alternative to diagnose alteration in DNA.
在本研究中，我们报告了人类精子的磁取向。样本取自17名捐献者。正常人类精子的长轴会与磁场（最大1特斯拉）垂直取向。在约1特斯拉的磁场下可实现完全取向，而异常精子的磁行为则有所不同。测得的取向程度与抗磁性物质磁取向的理论方程高度吻合。基于该方程进行数值分析后，发现正常精子的各向异性抗磁磁化率为Δ(χ) = 8×10⁻²⁰ J/T²。取向程度受头部、体部或尾部形状变化的影响。有人提出精子头部的DNA保留了强烈的磁各向异性，以抵消鞭毛微管保留的磁各向异性。近期研究表明人类精子细胞核具有明确的核结构，其中头部形态与精子染色质结构分析SCSA有显著相关性。那么，由于评估SCSA的方法可能既困难又昂贵，我们简单的磁取向技术可作为诊断DNA改变的一种替代方法。
