Effects of Fe3O4 Magnetic Nanoparticles on A549 Cells

Fe3O4 magnetic nanoparticles (MgNPs-Fe3O4) are widely used in medical applications, including magnetic resonance imaging, drug delivery, and in hyperthermia. However, the same properties that aid their utility in the clinic may potentially induce toxicity. Therefore, the purpose of this study was to investigate the cytotoxicity and genotoxicity of MgNPs-Fe3O4 in A549 human lung epithelial cells. MgNPs-Fe3O4 caused cell membrane damage, as assessed by the release of lactate dehydrogenase (LDH), only at a high concentration (100 μg/mL); a lower concentration (10 μg/mL) increased the production of reactive oxygen species, increased oxidative damage to DNA, and decreased the level of reduced glutathione. MgNPs-Fe3O4 caused a dose-dependent increase in the CD44+ fraction of A549 cells. MgNPs-Fe3O4 induced the expression of heme oxygenase-1 at a concentration of 1 μg/mL, and in a dose-dependent manner. Despite these effects, MgNPs-Fe3O4 had minimal effect on cell viability and elicited only a small increase in the number of cells undergoing apoptosis. Together, these data suggest that MgNPs-Fe3O4 exert little or no cytotoxicity until a high exposure level (100 μg/mL) is reached. This dissociation between elevated indices of cell damage and a small effect on cell viability warrants further study

A case of successful endoscopic removal in a patient who took aconite for the purpose of suicide.

　トリカブトは山野に自生しており，山菜・薬草と間違われ誤食事故を引き起こしている．また自殺目的に用いられることもある．トリカブト中毒ではアコニチンなどのアルカロイドにより経 口摂取間もなく重症不整脈をきたし，多量摂取例では致死的となりうる．トリカブトを摂取した患 者に対し内視鏡的除去を行い良好な予後を得たので報告する．症例は20代女性，自殺目的に観賞用トリカブトの根を切って飲み，当院へ救急搬送された．来院時自覚症状を認めなかった．胃洗浄を行ったがトリカブトは確認できなかった．摂取後早期であり，トリカブトの根を切って咀嚼せず飲み込んだという病歴から，トリカブト除去目的に上部消化管内視鏡を施行したところ胃内にトリカブトの根を認め内視鏡的に除去しえた．入院後症状の出現なく，心電図変化も認めなかった．経過良好であり翌日退院となった．来院時の胃液ではヒパコニチン 5.1 ng/ml，メサコニチン 21.0 ng/ml，アコニチン 1.1 ng/ml，ベンゾイルメサコニン 3.4 ng/ml が検出されたが，血清，尿からは検出されなかった．一般的にトリカブト中毒が疑われた場合，吸収阻害を目的に胃洗浄さらに活性炭の投与を行うとされている．本症例では，病歴から固形のトリカブトが胃内に残っていると推測し，早期に内視鏡的除去を行った結果，中毒症状を呈することなく経過した．固形物を咀嚼せずに飲み込んだこと，摂取から時間が経っていないこと，物質が吸収された場合致死的であることを満たす場合には，有効な治療法となる可能性がある．　Aconite grows wild in mountains and fields, and it is often mistaken for other edible or medicinal plants, resulting in poisoning. Whilst ingestion may be accidental, it is also sometimes used for the purpose of suicide. Aconitine and other alkaloid toxins may cause severe, often fatal arrhythmias in patients with aconite poisoning, especially after high oral intake. Herein, we report the endoscopic removal of aconite from a patient after intentional ingestion. A woman in her twenties was rushed to our hospital after consuming the roots of an ornamental aconite in an attempt to commit suicide. The patient exhibited no subjective symptoms on admission. Gastric lavage was performed, but no aconite was found. An upper gastrointestinal endoscopy was performed and the aconite root, found in the stomach, was removed. The patient exhibited no symptoms or ECG changes after admission. Aconitine alkaloids, such as hypaconitine (5.1 ng/mL), mesaconitine (21.0 ng/mL), aconitine (1.1 ng/mL), and benzoyl-mesaconine (3.4 ng/mL), were detected in the gastric juice but not in the serum or urine. The patient was discharged the following day. In general, when aconite poisoning is suspected, gastric lavage and activated charcoal are administered to inhibit absorption. The ingestion of solid materials without chewing may affect absorption time. Based on the history of this case, we assumed that solid aconite remained in the stomach, thus early endoscopic removal of the aconite resulted in no symptoms of poisoning. Hence, this may be an effective and fast treatment for aconite poisoning