Murros Kari, Wasiljeff Joonas, Macías-Sánchez Elena, Faivre Damien, Soinne Lauri, Valtonen Jussi, Pohja Marjatta, Saari Pekka, Pesonen Lauri J, Salminen Johanna M
Department of Neurology, Helsinki University Hospital, Helsinki, Finland.
Department of Geosciences and Geography, University of Helsinki, Helsinki, Finland.
Front Med (Lausanne). 2019 Jun 4;6:123. doi: 10.3389/fmed.2019.00123. eCollection 2019.
Magnetic iron oxide nanoparticles, magnetite/maghemite, have been identified in human tissues, including the brain, meninges, heart, liver, and spleen. As these nanoparticles may play a role in the pathogenesis of neurodegenerative diseases, a pilot study explored the occurrence of these particles in the cervical (neck) skin of 10 patients with Parkinson's disease and 10 healthy controls. Magnetometry and transmission electron microscopy analyses revealed magnetite/maghemite nanoparticles in the skin samples of every study participant. Regarding magnetite/maghemite concentrations of the single-domain particles, no significant between-group difference was emerged. In low-temperature magnetic measurement, a magnetic anomaly at ~50 K was evident mainly in the dermal samples of the Parkinson group. This anomaly was larger than the effect related to the magnetic ordering of molecular oxygen. The temperature range of the anomaly, and the size-range of magnetite/maghemite, both refute the idea of magnetic ordering of any iron phase other than magnetite. We propose that the explanation for the finding is interaction between clusters of superparamagnetic and single-domain-sized nanoparticles. The source and significance of these particles remains speculative.
磁性氧化铁纳米颗粒，即磁铁矿/磁赤铁矿，已在人体组织中被发现，包括大脑、脑膜、心脏、肝脏和脾脏。由于这些纳米颗粒可能在神经退行性疾病的发病机制中起作用，一项初步研究探讨了这些颗粒在10名帕金森病患者和10名健康对照者颈部皮肤中的存在情况。磁力测量和透射电子显微镜分析在每个研究参与者的皮肤样本中都发现了磁铁矿/磁赤铁矿纳米颗粒。关于单畴颗粒的磁铁矿/磁赤铁矿浓度，未出现显著的组间差异。在低温磁性测量中，约50K的磁异常主要在帕金森病组的真皮样本中明显。这种异常大于与分子氧磁有序相关的效应。异常的温度范围和磁铁矿/磁赤铁矿的尺寸范围，都反驳了除磁铁矿以外任何铁相的磁有序观点。我们提出，对这一发现的解释是超顺磁性和单畴尺寸纳米颗粒簇之间的相互作用。这些颗粒的来源和意义仍具有推测性。
