Polarization-resolved second-harmonic generation (PSHG) microscopy is widely used in investigating the structural and morphological alterations of collagen. However, the resolution of second-harmonic generation (SHG) imaging remains constrained by optical diffraction, resulting in the polarization extraction of collagen characteristics from the average properties of collagen fibers. In this study, multifocal structured illumination microscopy (MSIM) was combined with PSHG to achieve polarization-resolved super-resolution imaging of second-harmonic generation signals. For the first time to our knowledge, periodic structures with an average pitch of 277 nm were observed in mouse tail tendons using optical microscopy, and the orientation angle of fibrils within each period was found to exhibit an alternating arrangement along the axis in a regular pattern.

中文翻译：

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基于多焦点结构照明显微镜的偏振分辨超分辨率二次谐波产生成像

偏振分辨二次谐波发生（PSHG）显微镜广泛用于研究胶原蛋白的结构和形态变化。然而，二次谐波生成（SHG）成像的分辨率仍然受到光学衍射的限制，导致从胶原纤维的平均特性中偏振提取胶原特性。在这项研究中，多焦点结构照明显微镜（MSIM）与PSHG相结合，实现了二次谐波产生信号的偏振分辨超分辨率成像。据我们所知，首次利用光学显微镜在小鼠尾腱中观察到平均节距为277 nm的周期性结构，并且发现每个周期内原纤维的取向角呈现出沿轴以规则模式交替排列的结构。 。