Expression of Neural Cell Adhesion Molecule and Polysialic Acid in Cultured Spiral Ganglion Neurons / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Neural cell adhesion molecule (NCAM) and polysialic acid (PSA) function basically in cell adhesion and migration. In neural development, they are closely associated with axon pathfinding, synaptogenesis, neural cell migration, differentiation and myelination. The purpose of this study is to assess expression of NCAM and PSA expression in spiral ganglion neurons and Schwann cells and to postulate their functions. MATERIALS AND METHOD: Guinea pig spiral ganglion cells were harvested and cultured in vitro. The cells were grown and differentiated in culture medium together with brain derived neurotrophic factor (BDNF), neurotrophin 3 (NT-3) and glial cell derived neurotrophic factor (GDNF). After 1 week of culturing, the cells were fixed and immunocytochemical staining with beta-III tubulin, S-100, polysialic acid (PSA) and neural cell adhesion molecule (NCAM) were performed. We then checked axon growth rate with Axon Analyzer System(R). RESULTS: In the spiral ganglion culture, cultured neurons showed positive staining for beta-III tubulin, NCAM, and different expressions of PSA. S-100 positive glial cells (Schwann cells) showed different expressions of NCAM and no expression of PSA. Some NCAM positive neurons and Schwann cells were in contact each other. The growth rate of neuron was about 10-30 micrometer/h using Axon Analyzer System(R). CONCLUSION: We postulated that NCAM may play an important role in neural cell adhesion, myelination, fasciculation and ganglion formation. But PSA did not express the adhesive function of NCAM ; its absence may have been due to developmental reason. The differential expression of NCAM in the Schwann cells may indicate its different immunocytochemical characteristics and functions as shown in the CNS glial cells, astrocytes and oligodendrocytes.

Cecal rupture by Anoplocephala perfoliata infection in a thoroughbred horse in Seoul Race Park, South Korea

A 7-year-old Thoroughbred horse was admitted to the Equine Hospital, Korea Racing Association with signs of colic. Based on the size of impactions, the clinical signs, the results of abdominal paracentesis and medical treatment, the prognosis was poor. The horse died 3 hours later following hopeless discharge. At necropsy, the caecum and large colon were fully filled with fecal contents and there was a rupture (10 cm in dia) in the latero- ventral caecum. The mucosa of the ileo-caecal and caeco- colic valves appeared to the hyperemic, edematous and ulcerous. There were many tapeworms in the affected mucosa. Histopathologically, lesions included hyperaemia, a deep necrotic inflammatory lesion and ulcers in the mucosa and submucosa of ileo-caecal and caeco-colic valves. One hundred thirty four faecal samples were obtained from 16 stables and submitted to parasitic examination. A total of 4 genera of eggs were recovered: Stongylus spp (82.1%), Anoplocephala perfoliata (10.5%), Bovicola equi (0.7%) and Parascaris equorum (1.5%). The major findings in this study are the presence of A perfoliata and its suspected association with the colic which led into an eventual caecal rupture. This study indicates the needs for an epidemiological survey of colic that is associated with Anoplocephala.