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Taiji Sakamoto

Publications and source records attributed to Taiji Sakamoto.

61 records · Page 4Linked to original sources

Interleukin-8 expressed in the granulocytes of the eye in a patient with Behçet's disease complicated by lens-induced endophthalmitis.

BACKGROUND: Interleukin-8 (IL-8) is believed to be involved in the progression of intraocular inflammation. We sought the source of IL-8 in the enucleated eye of the present patient. CASE: A 40-year-old Japanese man was diagnosed as having Behçet's disease. His vision deteriorated due to persistent uveitis and secondary glaucoma. His left eye had lens-induced endophthalmitis. OBSERVATIONS: The left eye had to be enucleated, and it was investigated by an immunohistochemical analysis using antibodies for CD 1a (dendritic cells), CD 3 (T cells), CD 68 (monocytes/macrophages), interferon-gamma, or IL-8. Fibrovascular tissue had formed on and beneath the lens where inflammatory cells had infiltrated. Most of the mononuclear inflammatory cells were T cells. A large number of macrophages were observed especially around the lens. Interferon-gamma-positive cells were scattered, while IL-8 was observed only in the accumulated granulocytes, but not in either mononuclear cells or macrophages. CONCLUSION: IL-8 is thus considered to play a role in the progression of intraocular inflammation, and granulocytes are thought to be a possible source of IL-8 in endophthalmitis.

Adult↗

Analysis of HLA class I and class II gene polymorphisms in Japanese patients with human T-cell lymphotropic virus type 1-associated uveitis.

PURPOSE: To investigate the immunogenetic background of human T-cell lymphotropic virus type 1 (HTLV-1)-associated uveitis (HAU) that presents immune-mediated reactive changes in the uvea. METHODS: HLA class I and class II genes were studied in 51 patients with HAU, 192 asymptomatic HTLV-1 carriers, and 266 HTLV-1-seronegative controls using a high-resolution method of HLA DNA typing. The HLA alleles of HAU were compared with those of HTLV-1 carriers and healthy controls. RESULTS: We identified 62 distinct alleles of HLA-A, HLA-Cw, and HLA-B and 49 distinct alleles of HLA-DRB1 and HLA-DQB1 in patients with HAU, asymptomatic HTLV-1 carriers, and healthy controls. The relative frequencies of these HLA alleles did not differ among the three groups. CONCLUSION: The results suggest that HLA class I and class II genes do not contribute to susceptibility to HAU.

Alleles↗

Re-worsening factor after successful vitrectomy for diabetic retinopathy: optic disc fibrovascular proliferation and macular disease.

PURPOSE: To investigate the factors that influence the visual-changing pattern in proliferative diabetic retinopathy even after successful vitrectomy. METHODS: One hundred and forty-seven consecutive eyes were retrospectively reviewed for 6-48 (average 20) months, and were divided into the following 4 groups based on their changing pattern of vision: group A, the visual acuity improved postoperatively and maintained the maximal corrected vision throughout the observation period (n = 49); group B, the visual acuity improved postoperatively but deteriorated thereafter (n = 68); group C, the visual acuity remained the same as before operation (n = 17), and group D, the visual acuity deteriorated immediately after vitrectomy (n = 13). Various issues including systemic conditions, blood tests, preoperative ocular findings, the operative procedures and postoperative complications were reviewed based on the patient records. These issues were analyzed by Spearman's rank correlation, chi(2) test, an analysis of variance (ANOVA) and the Kruskal-Wallis test. Finally, the discriminate factors between groups A and B were examined by a stepwise logistic regression analysis. RESULTS: The following tendencies were observed in all 4 groups: younger patients tended to show a better visual-changing pattern (p = 0.02); patients with younger age at diabetes onset had a better visual-changing pattern after vitrectomy (p = 0.001), and a lower hemoglobin (Hb) A1c level is associated with a better visual changing pattern (p = 0.017). Preoperative rubeosis and macular detachment were frequently found in groups C and D, as well as postoperative rubeosis, vitreous bleeding and retinal detachment. Finally, a stepwise logistic regression analysis showed both fibrovascular proliferation (p = 0.016) from the optic disc and postoperative macular disease (p = 0.0009) to be significant factors for differentiating group A from group B. CONCLUSIONS: In addition to the factors which have already been indicated to affect the visual outcome of a vitrectomy, preoperative findings such as optic disc fibrovascular proliferation and postoperative macular disease were found to affect the visual-changing pattern after a successful vitrectomy. The optimal timing of surgery is very important not only in order to obtain good visual acuity but also to maintain good vision even after a successful vitrectomy.

Adult↗

Elevated adrenomedullin in the vitreous of patients with diabetic retinopathy.

Adrenomedullin (AM) is a multifunctional peptide with various physiological actions, including vasodilatation, a defense mechanism against microorganisms, the regulation of growth and the regulation of insulin and glucose. In this study, we measured the vitreous AM levels in patients with diabetes mellitus to determine its potential involvement in the pathogenesis of diabetic retinopathy (DR). We used an immunoradiometric assay to measure the vitreous AM concentrations in a total of 28 eyes: 13 with DR and 15 with macular holes (15 men and 13 women, 62.9 +/- 10.4 years old). The AM levels in the vitreous fluid of patients with DR (22.9 +/- 7.9 fmol/ml) were found to be significantly higher than the corresponding AM levels in patients with macular holes (4.7 +/- 1.1 fmol/ml) (p < 0.05). These results indicate that the increase in the vitreous AM is related to DR.

Adrenomedullin↗

Phylogenetic assessment of the mitochondrial DNA displacement loop haplotype in Japanese patients with Leber's hereditary optic neuropathy harboring the mitochondrial DNA G11778A mutation.

To investigate the anthropological background and the association of mitochondrial DNA (mtDNA) haplotype with the disease phenotype, the nucleotide sequence in the hypervariable segment of the displacement loop (D-loop) region of mtDNA was determined in Japanese patients with Leber's hereditary optic neuropathy (LHON) harboring the G11778A mutation. Genetic polymorphism of mtDNA was examined in 36 unrelated Japanese LHON patients who presented with bilateral optic nerve disease and had the mtDNA G11778A mutation. DNA was extracted from the peripheral blood after having obtained informed consent. The nucleotide sequence of the D-loop region (np 16,002-16,490) was directly determined. The intergenic deletion of the COII/tRNA(Lys) gene of mtDNA was also examined. From the data set of nucleotide alignments, the phylogeny of the mtDNA sequence and phenotypic diversity within the examined population were evaluated. One-base polymorphism was present at 37 different sites. The estimated value of nucleotide diversity was 0.69%. D-loop sequences were classified into 13 monophyletic clusters (CA to CM). There was not any definite ancestral haplotype of the D-loop sequence in the examined LHON population. Thus, the mutational event of G11778A appears to be independent of the evolutionary course in the D-loop haplotype. Patients with a CD plus CH cluster had a significantly older age at onset (p = 0.006), and had a family history being significantly lower as compared with patients with other clusters (p = 0.05). The mtDNA D-loop haplotype characterized by the presence of T16362C or C16290T, lacking G16129A and G16390A, may be a risk for older age at onset and other unusual clinical features in Japanese LHON patients with the G11778A mutation.

Base Sequence↗

Long-term results of pars plana vitrectomy combined with filtering surgery for neovascular glaucoma.

BACKGROUND AND OBJECTIVE: To analyze the effectiveness of vitrectomy combined with filtering surgery for neovascular glaucoma. PATIENTS AND METHODS: Twenty-one eyes with neovascular glaucoma underwent pars plana vitrectomy combined with filtering surgery between January 1995 and December 2003. Thirteen eyes (10 cases) had neovascular glaucoma secondary to proliferative diabetic retinopathy and 8 eyes (8 cases) had neovascular glaucoma secondary to central retinal vein occlusion. The initial intraocular pressures ranged from 21 to 70 mm Hg with full medication. All cases were observed for more than 12 months after the last surgery and the ophthalmic records were retrospectively reviewed. RESULTS: During the follow-up period, 19 eyes (90.5%) had intraocular pressures of less than 21 mm Hg with or without antiglaucoma eye drops, whereas 18 eyes (85.7%) had a stable or improved visual acuity. CONCLUSION: Vitrectomy combined with filtering surgery is considered to be an effective treatment for neovascular glaucoma to maintain the visual function for a long period.

Aged↗