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Satoko Shimizu

Publications and source records attributed to Satoko Shimizu.

12 recordsLinked to original sources
PubMed2004

A locus for posterior polymorphous corneal dystrophy (PPCD3) maps to chromosome 10.

Posterior polymorphous corneal dystrophy (PPCD) is an autosomal dominant disorder characterized by corneal endothelial abnormalities, which can lead to blindness due to loss of corneal transparency and sometimes glaucoma. We mapped a new locus responsible for PPCD in a family in which we excluded the previously reported PPCD locus on 20q11, and the region containing COL8A2 on chromosome 1. Results of a 317-marker genome scan provided significant evidence of linkage of PPCD to markers on chromosome 10, with single-point LOD scores of 2.63, 1.63, and 3.19 for markers D10S208 (at (circumflex)theta = 0.03), D10S1780 (at (circumflex)theta = 0.00), and D10S578 (at (circumflex)theta = 0.06). A maximum multi-point LOD score of 4.35 was found at marker D10S1780. Affected family members shared a haplotype in an 8.55 cM critical interval that was bounded by markers D10S213 and D10S578. Our finding of another PPCD locus, PPCD3, on chromosome 10 indicates that PPCD is genetically heterogeneous. Guttae, a common corneal finding sometimes observed along with PPCD, were found among both affected and unaffected members of the proband's sib ship, but were absent in the younger generations of the family. Evaluation of phenotypic differences between family members sharing the same affected haplotype raises questions about whether differences in disease severity, including differences in response to surgical interventions, could be due to genetic background or other factors independent of the PPCD3 locus.

Adult↗
PubMed2004

Endothelial nitric oxide contributes to the renal protective effects of ischemic preconditioning.

We determined whether endothelial nitric oxide synthase (eNOS) plays an important role in the renal protective effect of ischemic preconditioning (IP) against the ischemia/reperfusion-induced acute renal failure (ARF) by using eNOS-deficient (eNOS(-/-)) and wild-type (eNOS(+/+)) mice. Ischemic ARF was induced by occlusion of the left renal artery and vein for 45 min followed by reperfusion, 2 weeks after contralateral nephrectomy. IP, which consists of three cycles of 2-min ischemia followed by 5-min reperfusion, was performed prior to 45-min ischemia. In eNOS(+/+) mice, IP treatment markedly attenuated the ischemia/reperfusion-induced renal dysfunction and significantly improved histological renal damage such as tubular necrosis, proteinaceous casts in tubuli, and medullary congestion. Constitutive nitric oxide synthase activity in the kidney without IP was markedly decreased 6 h after reperfusion, but this decreased response was not observed in eNOS(+/+) mice with IP treatment. The improvement of renal dysfunction in eNOS(+/+) mice with IP treatment was abolished by pretreatment with N(G)-nitro-l-arginine, a nonselective NOS inhibitor, whereas aminoguanidine, an inducible NOS inhibitor, had no effect. Finally, no protective effects of IP on ischemia/reperfusion-induced renal dysfunction and histological damage were observed in eNOS(-/-) mice. These findings strongly support the view that eNOS-mediated NO production plays a pivotal role in the protective effect of IP on ischemia/reperfusion-induced ARF.

Animals↗
PubMed2004

Multiple elastofibromas.

Elastofibroma is an uncommon fibroelastic tumor or tumorlike process that usually occurs between the scapula and the chest wall of elderly patients. This condition is rarely reported in the dermatologic literature, because it infrequently arises in the skin or within the subcutaneous tissue. We present a 78-year-old man with 15 separate subcutaneous nodules on the buttocks and upper extremities together with bilateral subscapular nodules. All specimens taken from different lesions were histologically confirmed as elastofibromas. As far as we know, this case with 17 distinct elastofibromas demonstrates the largest number ever reported in a single patient. Although the pathomechanism of the occurrence of multiple elastofibromas is unknown, it should be included in the differential diagnosis of multiple subcutaneous nodules.

Aged↗
PubMed2003

A novel mutation in the OPA1 gene in a Japanese patient with optic atrophy.

PURPOSE: To report a novel mutation of the OPA1 gene in a Japanese patient with optic atrophy and to describe the clinical features of the patient. DESIGN: Observational case report. METHODS: Genomic DNA was extracted from leukocytes of four unrelated Japanese patients with optic atrophy. All the exons and splice sites of the OPA1 gene were amplified by polymerase chain reaction and directly sequenced. RESULTS: One patient with optic atrophy had a heterozygous Arg445His mutation in the OPA1 gene. The Arg445His mutation was detected neither in 110 control subjects nor in the patient's healthy family members. CONCLUSIONS: A novel mutation of the OPA1 gene, similar to those reported in Western countries, was detected in a Japanese patient with optic atrophy. Mutations of the OPA1 gene may contribute to the development of optic nerve atrophy in Japanese cases of optic atrophy.

Adolescent↗
PubMed2003

Clinicopathologic correlation and genetic analysis in a case of posterior polymorphous corneal dystrophy.

PURPOSE: To evaluate the clinical history, histopathology, and genetics of posterior polymorphous corneal dystrophy (PPMD) in a woman with a prominent retrocorneal membrane. DESIGN: Observational case report and genetic analysis of her family, UM:139. METHODS: Records were reviewed from a case and associated family members. The diagnosis of PPMD was based on clinical examination, immunohistochemical staining, electron microscopy, and screening of genetic markers from regions previously reported to be associated with PPMD. RESULTS: Over 17 years, the proband with PPMD had 25 ocular procedures performed for glaucoma, cataract, cornea, retina, and postoperative problems. A prominent retrocorneal membrane grew onto the crystalline lens and intraocular lens (IOL). Histopathology revealed stratified epithelial-like cells on iris from an iridectomy and stratified corneal endothelium on a corneal button. Electron microscopy on the cornea revealed microvilli, tonofilaments, and desmosomes consistent with endothelial transformation, which was confirmed by positive anticytokeratin (CK) AE1/AE3 and CAM 5.2 immunoreactivity. Negative immunoreactivity in epithelium and positive in endothelium with anti-CK 7 supported the diagnosis of PPMD rather than epithelial downgrowth. Multiple relatives were affected with PPMD with apparent autosomal dominant inheritance, but surprisingly, the PPMD, congenital hereditary endothelial dystrophy 1 (CHED1) and CHED2 loci on chromosome 20 and the collagen, type VIII, alpha-2 (COL8A2) gene were excluded by linkage and haplotype analyses. CONCLUSIONS: We are unaware of previous PPMD reports describing the unusual feature of a retrocorneal membrane extending onto the crystalline lens and IOL. In addition, this family suggests another PPMD locus.

Biomarkers↗
PubMed2002

[A novel mutation of the type 1 optic atrophy(OPA1) gene in a Japanese family with OPA1].

PURPOSE: To report a novel mutation of the type1 optic atrophy(OPA1) gene in a Japanese family with OPA1 and to describe the clinical features of this family. METHODS: Standard ocular examinations were performed on the proband and his two affected sons. The DNA sequence of all exons and splice sites of the OPA1 gene was determined to detect mutations. RESULTS: The proband and his sons had a heterozygous mutation of the OPA1 gene in the third nucleotide of intron 12(IVS12 + 3A-->T). Clinically, each patient had reduced visual acuity(onset within the first 6 years of life) and optic nerve pallor. The proband showed a central scotoma and generalized dyschromatopsia. This is the first report of OPA1 gene mutation in Japanese patients with familial optic atrophy. CONCLUSIONS: A mutation of the OPA1 gene was detected in a Japanese family with OPA1, which follows the same pattern as reported in Western countries. It is suggested that mutations of the OPA1 gene contribute to the development of optic nerve atrophy regardless of ethnic groups. Screening for the OPA1 gene mutation will be useful for diagnosis of OPA1 in Japanese patients.

Base Sequence↗
PubMedDate not supplied

Recurrent mutation of the KIF21A gene in Japanese patients with congenital fibrosis of the extraocular muscles.

PURPOSE: To report recurrent mutation of the KIF21A gene in three Japanese families in which some members have congenital fibrosis of the extraocular muscles type 1 (CFEOM1), and to describe the clinical characteristics of the families. METHODS: Standard ocular examinations were performed on 18 normal and affected members of three unrelated families. To detect mutations, we determined the DNA sequence of exons 8, 20, and 21 and the splice sites of the KIF21A gene. RESULTS: All affected members had a heterozygous mutation of the KIF21A gene in exon 21 (R954W). Clinically, each patient had congenital bilateral ptosis, an infraducted primary position of each eye, and the inability to raise either eye above midline. CONCLUSIONS: The KIF21A gene mutation R954W was detected in the patients with CFEOM1 screened in this study, all of whom were Japanese, reflecting similar reports from Europe, America, the Middle East, and Japan. We suggest that mutations of the KIF21A gene contribute to the development of CFEOM1 regardless of ethnicity. We also found that the delimitation of the KIF21A gene mutation site enabled us to efficiently detect the KIF21A gene mutation despite the large number of KIF21A gene exons.

Adult↗
PubMedDate not supplied

A novel mutation of the OPA1 gene in a Japanese family with optic atrophy type 1.

PURPOSE: To report a novel mutation of the OPA1 gene in a Japanese family with optic atrophy type 1 (OPA1) and to describe the clinical features of this family. METHODS: Standard ocular examinations were performed on the proband and his two affected sons. The DNA sequence of all exons and splice sites of the OPA1 gene was determined to detect mutations. RESULTS: The proband and his sons had a heterozygous mutation of the OPA1 gene in the third nucleotide of intron 12 (IVS12+3A-->T). Clinically, each patient had reduced visual acuity (onset within the first 6 years of life) and optic nerve pallor. The proband showed bilateral central scotomas and generalized dyschroatopsia. This is the first report of OPA1 gene mutation in Japanese patients with familial optic atrophy. CONCLUSIONS: A mutation of the OPA1 gene was detected in a Japanese family with OPA1, which follows the same pattern as reported in Western countries. It is suggested that mutations of the OPA1 gene contribute to the development of optic nerve atrophy regardless of ethnic groups. Screening for the OPA1 gene mutation will be useful for diagnosis of OPA1 in Japanese patients.

Adult↗