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Yosuke Okada

Publications and source records attributed to Yosuke Okada.

At least 37 records · Page 2Linked to original sources
PubMed2004

Adult-onset idiopathic progressive acro-osteolysis with proximal symphalangism.

We experienced a 57-year-old female with adult-onset non-congenital idiopathic acro-osteolysis combined with proximal symphalangism. At the age of 36, she developed severe pain and swelling of the toe base of both feet and underwent Clayton surgery. However, the size of her toes diminished progressively over the 5-year period after surgery. At the age of 41, she suffered pain and swelling of the proximal interphalangeal (PIP) joints of fingers of both hands. These PIP joints became rigid and inflexible. Subsequently, she noticed shortening of the little finger of both hands, followed later by shortening of the index, middle, and ring fingers. At the age of 57, the thumbs began to shorten. Laboratory and endocrinological examinations were not abnormal. Finally, we diagnosed her with acro-osteolysis combined with proximal symphalangism by radiological examination. In this case, previously unreported mutations of the Noggin gene were identified. This is the first case report of adult-onset, non-congenital idiopathic acro-osteolysis combined with proximal symphalangism.

Acro-Osteolysis↗
PubMed2004

A rare case of primary hyperparathyroidism with clear cell adenoma.

We report a 52-year-old woman who was noted to have elevated alkaline phosphatase (ALP), hypercalcemia (Ca: 11.7 mg/dL), and intact parathyroid hormone (intact PTH: 643.1 pg/mL), and then referred to our hospital with suspected hyperparathyroidism. Ultrasound examination of the neck and magnetic resonance imaging showed a mass region in the posterior aspect of the left lobe of the thyroid, and Tl-Tc subtraction scintigraphy showed Tl uptake at the same location. Based on laboratory and imaging studies, she was diagnosed with primary hyperparathyroidism. The excised parathyroid was a large mass measuring 6.8 x 2.8 x 1.9 cm in diameter and weighing 15.4 g. It was soft, covered with a thin capsule, did not infiltrate the thyroid parenchyma, and showed no evidence of malignant process. Histopathological examination showed that it was clear cell adenoma. There was no evidence of metastasis from the parathyroid tumor in other organs. The post-operative course was excellent, and serum PTH, Ca, and ALP levels returned to normal. Among parathyroid tumors, large adenomas are commonly considered to be more likely malignant, but in this case it was benign despite measuring more than 6 cm in diameter. The histopathological type of the adenoma was clear cell adenoma, a very rare type. We report a clear cell adenoma of the parathyroid gland, which has not been described previously in Japan.

Adenoma↗
PubMed2004

Etidronate prevents high dose glucocorticoid induced bone loss in premenopausal individuals with systemic autoimmune diseases.

OBJECTIVE: To assess the efficacy of etidronate and alfacalcidol in preventing glucocorticoid induced bone loss in premenopausal women and men starting high dose glucocorticoid therapy. METHODS: Premenopausal women (n = 16) and men (n = 5) who had just developed autoimmune diseases, and who agreed to use high dose glucocorticoid therapy for the first time, were randomized to receive alfacalcidol (1 micro g/day) alone (alfacalcidol group, n = 11); or alfacalcidol (1 micro g/day) and intermittent cyclical etidronate (200 mg/day for 14 days), given for 4 cycles (combined group, n = 10). They were treated with these medications as well as high dose glucocorticoids for 12 months. RESULTS: In the alfacalcidol group the percentage changes in bone mineral density (BMD) of the lumbar spine after 6 and 12 mo of therapy were -9.6 +/- 0.6% and -10.3 +/- 1.0%, respectively. However, in the combined group the percentage changes in lumbar spine BMD after 6 and 12 mo were -3.8 +/- 1.3% and -4.5 +/- 2.1%. The percentage lumbar spine bone loss rate in the combined group was significantly lower than in the alfacalcidol group at both 6 and 12 mo. After 12 mo the percentage change in femoral neck BMD was increased 2.3 +/- 1.5% in the combined group and was decreased 2.5 +/- 2.4% in the alfacalcidol group; this difference was also statistically significant. There were no significant differences in metabolic bone markers between the groups during the study. CONCLUSION: The results suggest that etidronate could prevent high dose glucocorticoid induced bone loss in premenopausal individuals with systemic autoimmune diseases.

Adjuvants, Immunologic↗
PubMed2003

Beta1 integrin/focal adhesion kinase-mediated signaling induces intercellular adhesion molecule 1 and receptor activator of nuclear factor kappaB ligand on osteoblasts and osteoclast maturation.

We have assessed characteristics of primary human osteoblasts, shedding light on signaling mediated by beta1 integrin. beta1 integrins are major receptors for these matrix glycoproteins. 1) Integrins beta1, alpha2, alpha3, alpha4, alpha5, alpha6, and alphav were highly expressed on primary osteoblasts. 2) Engagement of beta1 integrins on osteoblasts by cross-linking with specific antibody or ligand matrices, such as fibronectin or collagen, augmented expression of intercellular adhesion molecule 1 (ICAM-1) and receptor activator of nuclear factor kappaB ligand (RANKL) on the surface. 3) Up-regulation of ICAM-1 and RANKL on osteoblasts by beta1 stimulation was completely abrogated by pretreatment with herbimycin A and genistein, tyrosine kinase inhibitors, or transfection of dominant negative truncations of focal adhesion kinase (FAK). 4) Engagement of beta1 integrins on osteoblasts induced tartrate-resistant acid phosphatase-positive multinuclear cell formation in the coculture system of osteoblasts and peripheral monocytes. 5) Up-regulation of tartrate-resistant acid phosphatase-positive multinuclear cell formation by beta1 stimulation was completely abrogated by transfection of dominant negative truncations of FAK. Our results indicate that beta1 integrin-dependent adhesion of osteoblasts to bone matrices induces ICAM-1 and RANKL expression and osteoclast formation via tyrosine kinase, especially FAK. We here propose that beta1 integrin/FAK-mediated signaling on osteoblasts could be involved in ICAM-1- and RANKL-dependent osteoclast maturation.

Antibodies, Monoclonal↗
PubMed2003

[A case of Hypothyroid Graves' disease with extremely high titers of TSAb].

Graves' ophthalmopathy in hypothyroid state is called Hypothyroid Graves' Disease, which is a comparatively rare disease. We experienced a case of a 57 year old man with severe exophthalmos and diplopia, which are typical symptoms of Graves' opthalmopathy, and with an extremely high thyroid-stimulating antibody(TSAb) level. He also had a firm diffuse goiter and hypothyroidism with positive anti-thyroglobulin and anti-thyroid microsomal antigen. These findings suggested Hashimoto's thyroiditis. Severity of ophthalmopathy and TSAb level were improved during replacement therapy with T4. Although a thyroid stimulation-blocking antibody was also detected in this patient, we thought that hypothyroidism in this case was based on destructive change in the thyroid with Hashimoto's thyroiditis. Therefore, we should be aware of the fact that there are cases of hypothyroidism with Graves' ophthalmopathy and a high level of TSAb.

Graves Disease↗
PubMed2003

Role of cyclooxygenase-2 in bone resorption.

Prostaglandins (PGs) are abundant in bone and are potent regulators of bone cell function. Osteoblasts produce PGs, and this production is highly regulated by local and systemic factors. Bone resorption is a highly regulated process involving interactions of osteoclastic precursors with osteoblasts or stromal cells. Many factors that stimulate PGs production also stimulate resorption in organ and marrow culture. Cyclooxygenase (COX) is the rate-limiting enzyme in the conversion of arachidonic acid to PGs. There are two forms of COX, COX-1 and COX-2. COX-2 is an inducible primary-response or immediate early gene. COX-2 expression is induced by many factors through the transcriptional pathway in osteoblasts. Stimulated production of PGs by osteoblasts requires both the induction of COX-2 expression and the availability of arachidonic acid substrate. PGs are complex, potent regulators of bone cell function in vivo. PGE2, which may be the most important local eicosanoid in skeletal regulation, can stimulate resorption. We report that COX-2 expression and associated PG production are necessary for maximal resorption responses to 1,25 (OH)2D3 and parathyroid hormone (PTH). PGs can increase osteoclast formation by enhancing induction of the receptor activator of nuclear factor-kappa B ligand (RANKL) expression in osteoblasts and enhancing the action of RANKL on osteoclast precursors by inhibiting granulocyte macropharge-colony stimulating factor (GM-CSF). In vitro, PGE2 can stimulate the differentiation of both osteoblasts and osteoclasts, and the net balance of these two effects under physiologic or pathologic conditions in vivo is not yet clear. Our in vivo data suggest that a role for COX-2 in bone resorption may be most evident when bone resorption is accelerated. Some of the complexity of PG actions on bone can be explained by the multiplicity of receptors for PGs. There are at least four distinct receptors for PGE2 with differential signaling pathways that have not yet been fully elucidated. Further studies are needed to clarify the specific pathways of PGs action in bone. Once this is accomplished, it may be possible to identify therapeutic applications of manipulating PGs in skeletal disorders.

Animals↗
PubMed2003

Monocyte chemoattractant protein-1 induces scavenger receptor expression and monocyte differentiation into foam cells.

Accumulation of monocytes and the entrapment of oxidized-low-density lipoprotein (ox-LDL) in monocytes are important in the differentiation into "foam" macrophages and the pathogenesis of atherosclerosis. We investigated the role of monocyte chemoattractant protein-1 (MCP-1) in the expression of scavenger receptor (SCR) by using resting monocytes prepared by counterflow centrifugal elutriation. Our results showed that: (1) MCP-1 increased the expression of CD36 SCR by flow cytometric analysis. (2) MCP-1 increased incorporation of 125I-labeled ox-LDL and oil red O staining. (3) MCP-1 and ox-LDL enhanced in vitro transendothelial monocyte migration. (4) These functions were mediated at least in part via extracellular signal-regulated kinase (ERK) pathway. (5) MCP-1 and ox-LDL did not induce monocyte proliferation. Our results imply that MCP-1 is involved in the inflammatory process of atherosclerosis through the induction of SCR expression via the ERK pathway and differentiation of monocytes into foam macrophages, as well as induction of monocyte migration.

CD36 Antigens↗
PubMed2003

Impaired osteoclast formation in bone marrow cultures of Fgf2 null mice in response to parathyroid hormone.

Fibroblast growth factor (FGF)-2 and parathyroid hormone (PTH) are potent inducers of osteoclast (OCL) formation, and PTH increases FGF-2 mRNA and protein expression in osteoblasts. To elucidate the role of endogenous FGF-2 in PTH responses, we examined PTH-induced OCL formation in bone marrow cultures from wild type and mice with a disruption of the Fgf2 gene. FGF-2-induced OCL formation was similar in marrow culture from both genotypes. In contrast, PTH-stimulated OCL formation in bone marrow cultures or co-cultures of osteoblast-spleen cells from Fgf2-/mice was significantly impaired. PTH increased RANKL mRNA expression in osteoblasts cultures from both genotypes. After 6 days of treatment, osteoprotegerin protein in cell supernatants was 40-fold higher in vehicle-treated and 30-fold higher in PTH-treated co-cultures of osteoblast and spleen cells from Fgf2-/mice compared with Fgf2+/+ mice. However, a neutralizing antibody to osteoprotegerin did not rescue reduced OCL formation in response to PTH. Injection of PTH caused hypercalcemia in Fgf2+/+ but not Fgf2-/mice. We conclude that PTH stimulates OCL formation and bone resorption in mice in part by endogenous FGF-2 synthesis by osteoblasts. Because RANKL- and interleukin-11-induced OCL formation was also reduced in bone marrow cultures from Fgf2-/mice, we further conclude that endogenous FGF-2 is necessary for maximal OCL formation by multiple bone resorbing factors.

Acid Phosphatase↗
PubMed2003

Virilizing adrenocortical adenoma with Cushing's syndrome, thyroid papillary carcinoma and hypergastrinemia in a middle-aged woman.

We report a rare case of virilizing adrenocortical adenoma complicated with Cushing's syndrome, thyroid papillary carcinoma and hypergastrinemia. A 45-year-old woman had a history of amenorrhea for 10 years, hypertension for 8 years, and diabetes mellitus for 3 years. Physical examination showed a masculinized woman with severe hirsutism, male-like baldness, deep voice, acne in the precordia, and clitorism. Plasma testosterone, DHEA-S and urinary 17-KS were high, and plasma cortisol level was it at the upper limit of the normal range, but it did not show a diurnal rhythm nor was suppressed by 2 and 8 mg of dexamethasone. Abdominal CT scan showed a left adrenal tumor (4.5 cm in size). Adrenal scintigram revealed uptake of the tracer on the left side, and plasma cortisol concentration was high in a blood sample from the left adrenal vein. Left adrenalectomy was performed. Histopathological features of resected adrenal tumor were consistent with those of adrenocortical adenoma, consisting of tumor cells with eosinophilic compact cytoplasm. Immunohistochemical staining for steroidogenic enzymes showed reactivity for P450sec, 3 beta-HSD, P450c17, P450c21 and P450c11. Plasma testosterone and cortisol levels decreased to the normal range postoperatively. The patient was also found to have a papillary thyroid carcinoma and hypergastrinemia. Our patient is a rare case of virilizing adrenocortical adenoma associated with Cushing's syndrome, thyroid papillary carcinoma, and hypergastrinemia.

Adrenal Cortex Neoplasms↗
PubMed2003

Primary bilateral adrenal intravascular large B-cell lymphoma associated with adrenal failure.

We report a rare case of bilateral primary adrenal non-Hodgkin's lymphoma with adrenal failure. A 66-year-old woman developed symptoms of adrenal failure. The cause of adrenal failure was suspected to be malignant lymphoma based on the high levels of serum soluble interleukin-2 receptor and LDH. Bilateral adrenalectomy was performed and pathological examination showed intravascular large B-cell lymphoma (IVL). Although complete remission was achieved, recurrence occurred three months later with brain metastases. IVL should be suspected in patients with bilateral adrenal tumors who present with rapidly progressive adrenal failure.

Adrenal Gland Neoplasms↗
PubMed2003

[Prevention and treatment of glucocorticoid-induced osteoporosis].

Glucocorticoid (GC) is used to treat a wide variety of inflammatory and allergic diseases, but often brings about various adverse effects, including osteoporosis and subsequent bone fracture. GC-induced osteoporosis, thereby, should be treated and also be prevented. Accumulated evidence indicates that treatment with a bisphosphonate is recommended for prevention as well as treatment of GC-induced osteoporosis in all men and postmenopausal women, in whom will receive or have received long-term GC treatment. Further studies would provide additional options for treatment or prevention of GC-induced osteoporosis.

English Abstract↗
PubMed2002

[A case of hypothyroidism due to hashimoto disease that presented elevations of free T3 and free T4 by thyroid hormone autoantibodies].

When we commonly evaluate the thyroid function, we measure TSH, free T3 and free T4. However, there are some cases that are difficult to diagnose because of the existence of thyroid hormone autoantibodies. We experienced a case of a 14-year-old girl with diffuse struma whose TSH, free T3 and free T4 were elevated by detected with Amerlex M free T3 and free T4 kits, although she did not have any symptoms. As the free T4 level was low by the equilibrium dialysis method, we diagnosed this case as hypothyroidism due to chronic thyroiditis. Because we found thyroid hormone antibodies in her serum, we thought that this case presented pseudoelevations of free T3 and free T4 by the analogue method.

Adolescent↗
PubMed2002

H-Ras/mitogen-activated protein kinase pathway inhibits integrin-mediated adhesion and induces apoptosis in osteoblasts.

We have studied the relevance of H-Ras and its downstream effectors to osteoblast functions. 1) Purified human osteoblasts highly expressed integrins beta1, alpha4, alpha5, alpha6 and the activation epitope of beta1. However, these molecules were markedly down-regulated on osteoblasts transfected with expression vector encoding fully activated H-Ras(V12), H-Ras(V12)T35S, activating Raf-1/mitogen-activated protein kinase (MAPK), or an active Raf-1 but not on cells having H-Ras(V12)Y40C, a phosphoinositide 3-kinase (PI3K)-binding mutant. 2) Although osteoblasts spontaneously adhered to fibronectin and laminin in beta1-dependent manner, the expression of H-Ras(V12) or H-Ras(V12)T35S, but not H-Ras(V12)Y40C, in osteoblasts reduced their adhesion. 3) Osteoblasts bearing H-Ras(V12), H-Ras(V12)T35S, or Raf-1 failed to proliferate, whereas those with H-Ras(V12)Y40C proliferated well. (4) The up-regulation of Fas and down-regulation of Bcl-2 were observed in osteoblasts expressing H-Ras(V12), H-Ras(V12)T35S, or Raf-1. (5) Most of the cells having H-Ras(V12), H-Ras(V12)T35S, or Raf-1 became annexin-V(high)/propidium iodide (PI)(high or low) and terminal deoxynucleotidyl-transferase-mediated dUTP nick-end labeling (TUNEL)(high)/PI(low) after 24 and 72 h incubation, respectively. Thus, we propose that H-Ras signals followed by Raf-1/MAPK pathway but not PI3K not only reduces beta(1)-mediated adhesion of osteoblasts to matrix proteins but induces apoptosis presumably via the Fas up-regulation and Bcl-2 down-regulation.

Apoptosis↗
PubMed2002

A case of von Hippel-Lindau disease with bilateral pheochromocytoma, renal cell carcinoma, pelvic tumor, spinal hemangioblastoma and primary hyperparathyroidism.

A rare case of von Hippel-Lindau (VHL) disease with bilateral pheochromocytomas, right renal cell carcinoma, right pelvic carcinoma, spinal hemangioblastoma and primary hyperparathyroidism is described. A 78-year-old woman had a history of hypertension from her forties. She suffered from headache and body weight loss. Abdominal CT revealed bilateral adrenal tumors and right external renal tumors enhanced in early stage. MIBG scintigraphy exhibited a high accumulation of tracer in both adrenal glands. On the basis of the radiographic findings and endocrinological results, the patient was diagnosed as having bilateral pheochromocytomas and right renal cell carcinoma. A bilateral adrenectomy was performed, followed by surgery for resection of the renal cell carcinoma. The other resected right kidney showed a clear cell subtype that was determined to be renal cell carcinoma, and proved that the pelvic tumor was transient cell carcinoma. Spinal MRI showed spinal hemangioblastoma. von Hippel-Lindau (VHL) gene mutation for the patient was found. We diagnosed the patient as VHL because of the existence of spinal hemangioma and a VHL disease gene. Parathyroid echo revealed a hypoechoic space on the back of the left lobe, and serum calcium and intact PTH to be elevated. The patient was diagnosed as primary hyperparathyroidism. We report the first case of a patient with VHL disease complicated with bilateral pheochromocytomas, right renal cell carcinoma, right renal pelvic carcinoma and primary hyperparathyroidism. The life expectancy of affected individuals has been less than 50 years. Since the prognosis may be improved by an early diagnosis, affected individuals with VHL complexes should undergo cranial, spinal MRI and abdomen CT. The families may benefit from presymptomatic detection of affected gene carriers and the exclusion of at-risk family members by negative test results.

Adrenal Gland Neoplasms↗
PubMed2002

Cell-to-Cell adhesion via intercellular adhesion molecule-1 and leukocyte function-associated antigen-1 pathway is involved in 1alpha,25(OH)2D3, PTH and IL-1alpha-induced osteoclast differentiation and bone resorption.

Cell-to-cell interaction is required for the differentiation of osteoclast precursors as well as for osteoclast function. The present study was undertaken to determine whether 1,25 dihydroxyvitamin D3 (1,25D), PTH, IL-1alpha and PGE2 depend on cell-to-cell interactions through the intercellular adhesion molecule (ICAM)-1/leukocyte function-associated antigen (LFA)-1 pathway in osteoclast formation and bone resorption. We found that mouse osteoblasts expressed ICAM-1 and that the expression was increased by treatment with PTH, IL-1alpha or 1,25D, but not by PGE2. In resorption assays measuring either 45Ca release from bone organ cultures or pit formation in bone cell cultures, 1,25D-, PTH- and IL-1alpha-stimulated resorption was inhibited by anti-ICAM-1 monoclonal antibody (mAb) and/or anti-LFA-1 mAb, while basal and PGE2-stimulated bone resorbing activities were not affected by these mAbs. Furthermore, in a mouse bone marrow culture system, stimulation of osteoclast-like (OCL) cell formation by 1,25D (10 nM), PTH (10 ng/ml) or IL-1alpha (10 ng/ml) was inhibited by the addition of anti-ICAM-1 mAb and/or anti-LFA-1 mAb. In a coculture system of murine spleen cells and osteoblasts, the ICAM-1/LFA-1 interaction was also involved in 1,25D-, PTH- and IL-1alpha-stimulated TRAP-positive MNC formation. However, anti-ICAM-1 mAb and anti-LFA-1 mAb did not alter either 1,25D- or PTH-stimulated receptor activator of NF-kappaB ligand (RANKL) mRNA transcription in bone marrow cultures. Taken together, we here propose that ICAM-1-mediated cell-to-cell adhesion of osteoblasts and osteoclast precursors is involved in RANKL-dependent osteoclast maturation stimulated by 1,25D, PTH, and IL-1alpha.

Animals↗
PubMed2002

[Not Available].

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Journal Article↗