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Nishi-Tokyo-shi, Japan

Iwata M.,Nippon Veterinary and Life Science University | Ochi H.,Nippon Veterinary and Life Science University | Asou Y.,Tokyo Medical and Dental University | Haro H.,Yamanashi University | And 6 more authors.
PLoS ONE | Year: 2013

Intervertebral disc (IVD) degeneration greatly affects quality of life. The nucleus pulposus (NP) of chondrodystrophic dog breeds (CDBs) is similar to the human NP, because the cells disappear with age and are replaced by fibrochondrocyte-like cells. However, because IVD develops as early as within the first year of life, we used canines as a model to investigate in vitro the mechanisms underlying IVD degeneration. Specifically, we evaluated the potential of a three-dimensional (3D) culture of healthy NP as an in vitro model system to investigate the mechanisms of IVD degeneration. Agarose hydrogels were populated with healthy NP cells from beagles after performing magnetic resonance imaging, and mRNA expression profiles and pericellular extracellular matrix (ECM) protein distribution were determined. After 25 days of 3D culture, there was a tendency for redifferentiation into the native NP phenotype, and mRNA levels of Col2A1, COMP, and CK18 were not significantly different from those of freshly isolated cells. Our findings suggest that long-term 3D culture promoted chondrodystrophic NP redifferentiation through reconstruction of the pericellular microenvironment. Further, lipopolysaccharide (LPS) induced expression of TNF-α, MMP3, MMP13, VEGF, and PGES mRNA in the 3D cultures, creating a molecular milieu that mimics that of degenerated NP. These results suggest that this in vitro model represents a reliable and cost-effective tool for evaluating new therapies for disc degeneration. © 2013 Iwata et al. Source

Aikawa T.,Aikawa Veterinary Medical Center | Aikawa T.,Nippon Veterinary and Life Science University | Shibata M.,Aikawa Veterinary Medical Center | Asano M.,Aikawa Veterinary Medical Center | And 3 more authors.
Veterinary Surgery | Year: 2014

Objectives: To compare data for French Bulldogs and Dachshunds that had hemilaminectomy for thoracolumbar intervertebral disc extrusion (T-L IVDE) by 1 surgeon and to evaluate the association between IVDE and congenital vertebral anomalies. Design: Retrospective case series. Animals: French Bulldogs (n=47) and 671 Dachshunds. Methods: Age, gender, vertebral anomaly, kyphosis/kyphoscoliosis, IVDE site, non-recovery and progressive hemorrhagic myelomalacia development from grade 5 (paraplegia without deep nociception) were compared between the 2 breeds. Results: French Bulldogs were significantly younger (P= 00001), more likely to be male (P= 023), and more likely to have a congenital vertebral anomaly and kyphosis/kyphoscoliosis (P < .00001) than Dachshunds. The frequencies of French Bulldogs with IVDE within typical sites (T11-L3) were significantly lower (P= 0005) and within caudal sites (L3-L7) significantly higher (P= 0001) compared with Dachshunds. None of the French Bulldogs had IVDE within the kyphotic/kyphoscoliotic segment. The frequency of lumbar IVDE (L1-L5) in French Bulldogs with kyphosis/kyphoscoliosis was significantly higher (P= 003) compared with French Bulldogs without kyphosis/kyphoscoliosis. In grade 5 dogs, the risk of developing progressive hemorrhagic myelomalacia in French Bulldogs was significantly higher (P= 03) than in Dachshunds. Conclusion: The distribution of IVDE site in French Bulldogs within the thoracolumbar and lumbar spine was different from Dachshunds. IVDE sites were not located at the sites of vertebral anomaly. French Bulldogs appeared to have T-L IVDE at younger ages, with higher male predisposition and higher risk of developing progressive hemorrhagic myelomalacia from grade 5 compared with Dachshunds. © 2014 by The American College of Veterinary Surgeons. Source

Aikawa T.,Aikawa Veterinary Medical Center | Shibata M.,Aikawa Veterinary Medical Center | Sadahiro S.,Aikawa Veterinary Medical Center
Veterinary and Comparative Orthopaedics and Traumatology | Year: 2013

Objective: To describe the diagnostic findings, surgical technique and outcome in dogs with thoracolumbar intervertebral disc associated dynamic compression. Study design: Retrospective case series. Animals: Client owned dogs (n = 11). Methods: Medical records (2005-2010) of dogs with a stress myelographic diagnosis of spinal cord injury due to thoracolumbar intervertebral disc-associated dynamic compression with inconclusive compression in the neutral myelographic views that had hemilaminectomy and vertebral stabilization were reviewed. Data on pre- and postoperative neurologic status, diagnostic findings, surgical techniques and outcomes were retrieved. Follow-up clinical and radiographic evaluations were performed immediately, and at approximately one, two, and six months postoperatively as well as at annual followup examinations. Results: The stress myelography demonstrated distinct ventral dynamic compression due to bulging of the disc and additional dorsal compression due to infolding of the ligamentum flavum in some cases. The median percentage of post-stress reduction in spinal cord height on the lateral view was 18.0% (9.8-27.2%). All dogs recovered after surgery and at follow-up examinations were still ambulatory (median: 45 months, range: 7 to 94 months). Conclusions and clinical relevance: Thoracolumbar intervertebral disc degeneration may result in disc-associated dynamic compression. Stress myelography was an effective means of diagnosing this condition and hemilaminectomy with vertebral stabilization was an effective treatment resulting in long-term neurological improvement in all dogs. © Schattauer 2013. Source

Aikawa T.,Aikawa Veterinary Medical Center | Sadahiro S.,Aikawa Veterinary Medical Center | Nishimura M.,Aikawa Veterinary Medical Center | Miyazaki Y.,Aikawa Veterinary Medical Center | Shibata M.,Aikawa Veterinary Medical Center
Veterinary and Comparative Orthopaedics and Traumatology | Year: 2014

A four-year-old, female spayed Domestic Longhaired cat was referred for evaluation with a two month history of initial inability to jump progressing to ambulatory tetraparesis. Magnetic resonance imaging studies demonstrated a cystic lesion arising from the composite occipito- atlanto-axial joint cavity and extending to the region of the occipital bone and the axis. The lesion surrounded the spinal canal, causing moderate dorsal spinal cord compression at the atlanto-occipital joint. A dynamic myelographic study demonstrated attenuation of the dorsal contrast column at the atlanto- occipital joint when the cervical spine was positioned in extension. Partial excision of the cyst capsule by a ventral approach resulted in long-term (64 months) resolution of clinical signs. Histological evaluation was consistent with a ganglion cyst. An intra- spinal ganglion cyst arising from the composite occipito-atlanto-axial joint cavity may be considered as an uncommon differential diagnosis for cats with cervical myelopathy. © Schattauer 2014. Source

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