• Toxicological Research
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• v.13 no.4
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• pp.317-322
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• 1997

Acute delayed neurotoxicity of KH-502 [O.O-Diethyl O-(1-phenyyl-3-trifluoromethyl-5-pyrazoyl) thiophosphoric acid ester], an insecticide synthesized newly in Korea, was studied in White Leghorn hens. The doses were determined on the basis of preliminary $LD_{50}$ study. High, middle and low doses were determined to be 1123 mg/kg, 762 mg/kg and 518 mg/kg, respectively. The animals were pretreated with atropine (30 mg/kg) prior to administration of KH-502. The chemical was administrated at the first and 21st day of the study. As positive controls, animals were admlnistrated with triorthocresylphosphate (TOCP 1000 mg/kg and 500 mg/kg). Animals administrated with TOCP or KH-502 were sacrificed by perfusion-fixation at 21st and 42nd day of the study, respectively. The central and peripheral nerve tissues were routinely treated for microscopic observation. As results, eight, three, one, and one chickens died within 2 day after adminiatration with signs of cholinergic acute toxicity in high, middle low and TOCP dose-group (500 mg/kg), respectively. No abnormal clinical signs were observed in the survived chickens administrated with KH-502 in the duration of the study. The chickens in positive control groups showed ataxia and incoordination at the 14th day after administration of TOCP. From necropsy, macroscopic changes were not observed in all groups including positive control groups. Histopathologically, oxonal swelling with myelin loss, focal gliosis, distention around axonal space were observed in the spinal cords of the chickens administrated with TOCP 1000 mg/kg. The lesions were distinct in the dorsal and lateral funiculi of cervical spinal cord, in the lateral and ventral funiculi of thoracic spinal cord and in ventral funiculi of lumbosacral spinal cord. Axonal swelling and mlcrogliosis were infrequently observed in the chickens of other groups including negative control one. However, they were nonspecifically distributed in the spinal cords. In this study, we concluded that the new chemical, KH-502 did not have acute delayed neurotoxicity in White Leghorn hens.

• Korean Journal of Veterinary Research
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• v.41 no.4
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• pp.591-596
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• 2001

The chicks from 6 field broiler farms revealed peripheral neuropathy including leg weakness, curled toes and drooped wings. Grossly distinctive enlargements of sciatic nerve, branchial nerve and lumbar nerve were observed in the chicks. Histologically nerve lesions consisted of demyelination of myelin sheaths, Schwann cell proliferation and swelling, and interstitial edema in the peripheral nerves of all birds examined. Axonal swelling and infiltration of small lymphocytes were observed, but not a primary lesion. After treatment of riboflavin, neurological disorder was markedly recovered. From these results, it is suggested that the peripheral nerve lesions in these cases were caused by dietary riboflavin deficiency.

• Journal of Veterinary Clinics
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• v.19 no.2
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• pp.247-249
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• 2002

A 6-month-old female Pekingese was euthanized due to poor progrosis after 1 month history of neurologic signs that include depression, ataxia, urination and defecation difficulty. At necropsy, no significant gross abnormalities were noted Histologically, neuronal vacuolation was noted in the brain, primarily cerebellum and occasionally in the brain stem area. Neuronal necrosis and secondary axonal swelling were also observed. Differential diagnoses were able to rule out other diseases which can induce neuronal vacuolation such as lysosomal storage disease, prion infection, and postvaccinal change.

• Annals of Clinical Neurophysiology
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• v.9 no.2
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• pp.43-50
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• 2007

Analysis of intraepidermal nerve fibers using skin biopsy is a recently developed technique, providing diagnostic information on small fiber neuropathies. The specimens are obtained by 3 mm punch biopsy, which is safe and minimally invasive. Immunohistochemical staining by Protein gene product (PGP) 9.5 demonstrate not only intraepidermal nerve fibers but dermal structures, such as sweat gland and erector papillae. Up to now, many studies agree that intraepidermal nerve fiber density is dramatically reduced in various sensory neuropathies. The utility of density measure was confirmed with high sensitivity in the diagnosis of sensory neuropathy, comparable to sural nerve biopsy or quantitative sensory testing. Besides quantitative methods, morphological changes like axonal swelling and fragmentation can be used as predegenerative markers. This article reviews the technique of skin biopsy and clinical and experimental usefulness of skin biopsy in diagnosing and monitoring peripheral neuropathies.

• Korean Journal of Veterinary Research
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• v.48 no.4
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• pp.463-467
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• 2008

Granulomatous meningoencephalomyelitis (GME) is a sporadic, idiopathic, non suppurative inflammatory disease of the canine central nervous system. GME appears to have a worldwide distribution and to occur mostly in young to middle-age dogs of small breeds. A 6-year-old female mixed dog with wry neck, ataxia and rolling was submitted to the Cheju National University for diagnosis. Grossly, in the brain, cerebrospinal fluid was mildly increased and dilatation of the subarachnoid blood vessels was observed. Histopathologically, the lesions were characterized by perivascular cuffs of lymphocytes, various numbers of macrophages and plasma cells in the brainstem and cerebral white matter. Numerous granuloma composed of lymphocytes and histiocytes were scattered throughout the brainstem. Two malacic foci characterized by axonal swelling and gitter cell infiltration with hemorrhage were noted in the medulla oblongata and cerebellum. Special stains failed to demonstrate any infectious agents. Immunohistochemically, the infiltrated cells demonstrated strong positive reactions for CD3, a marker for T lymphocytes origin. Based on the clinical signs, histopathology, and immunohistochemistry, this case was diagnosed as GME in a mixed dog.

• Archives of Craniofacial Surgery
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• v.20 no.1
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• pp.71-74
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• 2019

Schwannoma is a benign tumor rarely found in the head and neck and much less commonly found in the intraparotid facial nerve. It is a slow-growing encapsulated tumor originating from the Schwann cells or axonal nerve sheath. It can occur anywhere along the course of the facial nerve. Patients may present with symptoms of facial palsy, but the most common presenting symptom is an asymptomatic swelling. Diagnosis is usually difficult before surgical removal and histopathological examination. We report a rare case of intraparotid facial nerve schwannoma in a 57-year-old female who had sustained a mass of the right preauricular area for 3 years. She reported no pain or facial muscle weakness. Enhanced computed tomography findings revealed the impression of pleomorphic adenoma. However, intraoperative gross findings were not characteristic of pleomorphic adenoma, and a frozen biopsy was performed resulting in the impression of a nerve sheath tumor. We performed an extracapsular surgical excision without parotidectomy. Permanent histopathology and immunohistochemistry reports diagnosed the mass as schwannoma. There were no complications including facial palsy after surgery. No recurrence was found at 6 months after surgery.

• Radiation Oncology Journal
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• v.4 no.2
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• pp.107-113
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• 1986

Radiation myelitis is a rather rare, but irreversible fatal complication. Etiology, pathologic change, clinical symptoms and the method of diagnosis have been studied with animal experiments and human necropsies. In spite of massive studies, pathogenesis of post-irradiation myelitis and the level of tolerance dose still remain controversial. Thoracolumbar spine of 110 hybrid mice were irradiated with orthovoltage x-ray machine. Mild capillary congestion and axonal swelling were observed in 1,000 rad irradiated specimens. Focal necrosis in 3,500 rad specimens, fragmentation of neural tissue in 4,000 rad specimens were also observed. These results suggest that 5,000 rad is not a completely safe tolerable dose which have been accepted and we cannot exclude direct radiation damage to news tissue as the causative pathology of radiation myelitis in addition to blood vessel damage.

• Journal of Veterinary Clinics
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• v.36 no.6
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• pp.340-344
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• 2019

A 14-month-old Thoroughbred colt with hind limbs lameness was referred to Equine Hospital of Jeju National University. During physical examination, the patient could not walk in a straight line but wobbled especially with hind limbs. He hesitated when backing and crossed hind limbs while circling tightly by protracting the outer hind limb keeping the inner hind limb stationed. Stenosis was observed between the 2nd (C2) and 3rd (C3), and the C3 and 4th (C4) cervical vertebrae on radiographs. The colt diagnosed as cervical stenotic myelopathy (CSM) based on the clinical signs and radiological findings. To confirm the diagnosis, postmortem computed tomography (CT) and histopathologic examination were performed after the euthanasia. The CT images revealed severe compression of the spinal cavity and cord between C3 and C4 cervical vertebrae. Grossly, there was compression of the spinal cord between the C3 and C4 cervical vertebrae. Histopathologically, severe axonal swelling and demyelination characterized by vacuolation and cavity formation were observed in the white matter of the spinal cord, especially in C3 and C4. CSM is problematic in the horse racing industry because of abnormal walking. This case report of CSM may offer information for diagnosis of the disease in the equine veterinary fields in the Republic of Korea.