1.Aconite induced myelo-optic neuropathy in a rabbit model.
Kui Duk SUK ; Kyung Cheol YOON ; Jae Pil SHIN ; Sang Ha KIM
Korean Journal of Ophthalmology 1994;8(2):77-82
Aconite is a common remedy of herb doctors and is widely used in the Far East. Clinical aspects of the visual disturbance produced by this drug have been described, but little is known about its pathology. Tinctura aconiti (0.6 mg of total alkaloid/kg 2x) was administered intraperitoneally in rabbits to evaluate its toxic effects on the visual system. The alteration in the visual evoked potential following aconite injection consisted of a delay in the onset and peak latency. Histopathologically, there were damages to the myelin sheath of the visual pathway, spinal cord and peripheral nerves. These findings suggest that aconite may cause primarily myelo-optic neuropathy.
Aconitum/administration & dosage/*toxicity
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Animals
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Evoked Potentials, Visual/*drug effects
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Injections, Intraperitoneal
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Myelin Sheath/*drug effects/ultrastructure
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Optic Nerve/*drug effects/ultrastructure
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Optic Nerve Diseases/*chemically induced/pathology
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Rabbits
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Spinal Cord/*drug effects/ultrastructure
2.Acellular nerve allograft by chemical extraction in humans.
Hong-bin ZHONG ; Shi-bi LU ; Shu-xun HOU ; Qing ZHAO
Chinese Journal of Surgery 2003;41(1):60-63
OBJECTIVETo develop a procedure by which Schwann cells and myelin in the peripheral nerve could be removed while the basal lamina tubes remained intact, and to obtain a thick and long acellular nerve allograft in humans.
METHODSFour ulnar nerves 10.0 cm long and 4.0 - 5.0 mm in diameter were excised from a donated male body and cleaned from external debris. The nerves were treated with a solution of Triton X-100 and a solution of sodium deoxycholate at room temperature. After a final wash in water, the nerves were stored in phosphate-buffered saline (PBS, pH 7.2) at 4 degrees C. HE, luxol fast blue and fibrin staining were performed to visualize cells, myelin and basal membranes respectively and immunohistochemical staining was performed to visualize the presence of laminin, a Schwann cell lamina component, both in fresh and acellular nerve segments. To reveal overall structure better, methylene blue-fuchsin staining was performed in semithin section. The ultrastructure of acellular and fresh nerves were observed and photographed in a transmission electron microscope.
RESULTSThe acellular human ulnar nerve was white long cylinder with well elasticity and ductility. HE, myelin and fibrin staining revealed that cells, axons and myelin sheath were removed and basal membrane was preserved after extraction procedure. Staining for the presence of laminin showed that the Schwann cell basal lamina component were present in the nerves after chemical treatment. Methylene blue-fuchsin staining and transmission electron microscopy showed that the myelin sheaths were absent in the extracted nerve segments and empty basal lamina tubes remained in the endoneurium.
CONCLUSIONSWe developed an extracted procedure with the detergents of Triton X-100 and deoxycholate, by which cells, axons and myelin sheaths could be removed from a human ulnar nerve while the basal lamina tubes remain intact and a thick long acellular nerve allograft is obtained. The laminin, a Schwann cell basal lamina component, can be preserved in the acellular nerve.
Adult ; Axons ; drug effects ; Cell Separation ; methods ; Deoxycholic Acid ; pharmacology ; Humans ; Male ; Myelin Sheath ; drug effects ; Octoxynol ; pharmacology ; Transplantation, Homologous ; Ulnar Nerve ; cytology ; transplantation ; ultrastructure