Publications by authors named "Ken'ichiro Narusawa"

Spinal osteoarthritis including disc degeneration is a very common condition in the axial skeletons of aged people. Recently, spinal osteoarthritis has been shown to be influenced by specific genetic risk factors. Vertebral osteophytes, endplate sclerosis, and intervertebral disc narrowing are recognized as radiographic features of spinal disc degeneration.

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HTRA1 (high-temperature requirement A1) has been implicated in the modulation of various disease pathologies. HTRA1 expression is upregulated in osteoarthritic joints, suggesting that it may contribute to the development of this debilitating disease. Moreover, recent reports have shown that the rs11200638, a single nucleotide polymorphism (SNP) in the promoter region of the HTRA1 gene, is strongly associated with an increased prevalence of age-related macular degeneration (AMD).

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Study Design: Cross sectional and prospective observational study in Japanese postmenopausal women.

Objective: The aim of the study was 2-fold. The first was to investigate what kind of comorbidities could be found in conjunction with back pain in Japanese postmenopausal women.

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Study Design: An association study investigating the genetic etiology for spinal disc degeneration.

Objective: To determine the association of single-nucleotide polymorphism (SNP) in the insulin-like growth factor-1 receptor (IGF1R) with spinal disc degeneration.

Summary Of Background Data: Insulin-like growth factor-1 (IGF-1) signaling pathway is involved in cartilage development and homeostasis, suggesting that genetic variations of genes involved in this pathway may affect the pathogenesis of cartilage-related diseases, such as disc degeneration.

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The Wnt-beta-catenin signaling pathway that regulates bone density is also involved in cartilage development and homeostasis in vivo. Here, we assumed that genetic variation in Wnt-beta-catenin signaling genes can affect the pathogenesis of cartilage related diseases, such as osteoarthritis. Wnt-1-induced secreted protein 1 (WISP1) is a target of the Wnt pathway and directly regulated by beta-catenin.

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Study Design: An association study investigating the genetic etiology for spinal osteoarthritis.

Objective: To determine the association of single-nucleotide polymorphism (SNP) causing an amino-acid change (Q89R) in the low-density lipoprotein receptor-related protein 5 (LRP5) coding region with spinal osteoarthritis.

Summary Of Background Data: Wnt/beta-catenin signaling pathway regulates bone density through a Wnt coreceptor LRP5.

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The vitamin-K-dependent gamma-glutamyl carboxylase (GGCX) carboxylates vitamin-K-dependent proteins including bone Gla protein (osteocalcin) and matrix Gla protein, which play important roles in bone metabolism. Therefore, GGCX polymorphism might explain in part individual susceptibility to osteoporosis. In the present study, polymorphisms in the exons of this gene were screened in Japanese elderly women and a non-synonymous single nucleotide polymorphisms (SNP) were found; c.

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Objective: The correlation between postoperative spinal cord enlargement at the most compressive disc level and clinical outcome is controversial. The relationship between spinal cord enlargement at neurologically symptomatic disc level and clinical recovery has not been explored. The purpose of this study was to clarify the relationship between postoperative spinal cord enlargement at neurologically symptomatic disc level and neurologic outcome.

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The present study was designed to determine the effects of glucocorticoid (GC) on bone turnover, minerals, structure, and bone mechanical properties in minipigs. Six 8-month-old Göttingen minipigs were subcutaneously injected with prednisolone (PN, 0.5 mg/kg body wt (BW)/day, 5 days/week for 26 weeks (Group GC)), 6 were treated with vehicle alone (Group VC), and 4 were sacrificed at start of the study for baseline controls (Group BC).

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