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T Tsuru

Publications and source records attributed to T Tsuru.

101 records · Page 6Linked to original sources

Okadaic acid enhances human T cell activation and phosphorylation of an internal substrate induced by phorbol myristate acetate.

Okadaic acid is a potent tumor promoter and an inhibitor of serine/threonine-specific protein phosphatases. We studied the effect of okadaic acid in human T cell activation and phosphorylation of internal substrates. Okadaic acid at up to 4 nM enhanced phorbol myristate acetate (PMA)-induced proliferation and CD25 (IL-2 receptor, p55) expression, although it showed no activation by itself. Okadaic acid induced hyperphosphorylation of a 60 kDa protein in T cells as well as non-T cells, as reported in fibroblasts and keratinocytes. Preincubation with 4 nM okadaic acid enhanced PMA induced phosphorylation of the 80 kDa protein, an internal substrate of protein kinase C in T cells. These results suggest that okadaic acid inhibited dephosphorylation of protein kinase C specific substrates, and as a result, enhanced T cell activation mediated by protein kinase C pathway.

Ethers, Cyclic↗

Long-term outcome of systemic cyclosporine treatment following penetrating keratoplasty.

PURPOSE: To perform a retrospective study to evaluate the long-term outcome of systemic cyclosporine treatment as an adjunct to topical corticosteroid treatment after penetrating keratoplasty (PKP). METHODS: Twenty-six high-risk patients (27 eyes) who received systemic cyclosporine following PKP for an average of 5.4 months were compared with another series of 57 patients (57 eyes) who did not receive cyclosporine after PKP. RESULTS: Endothelial rejection developed in 2 cases during cyclosporine treatment and in 6 cases after discontinuation. The rate of rejection-free graft survival was similar between the treated and the control groups. The control group showed a significantly higher rate of graft survival than the treated group. As side effects in the treatment group, transient elevation in blood urea nitrogen or creatine developed in 7 cases. Increase in glutamate oxaloacetate transaminase (GOT) or glutamate pyruvate transaminase (GPT) developed in 4 cases. Severe side effects were absent throughout the series in both groups of patients. CONCLUSION: Systemic cyclosporine treatment for several months did not reduce the incidence of rejection nor improve the rate of graft clarity in the long term in high-risk patients after PKP.

Adult↗

Restriction enzyme analysis of mitochondrial DNA of Acanthamoeba strains isolated from corneal lesions.

Although Acanthamoeba keratitis has been recognized as one of the important infectious diseases of the cornea, especially in contact lens wearers in recent years, its taxonomy has not been well established. We carried out mitochondrial DNA (mtDNA) analysis of the Acanthamoeba organisms isolated from corneal lesions in four eyes of three patients who had suffered from keratitis. The mtDNA was analyzed by restriction fragment length polymorphism (RFLP) using restriction enzymes Bg/II and EcoRI. The RFLP analyses revealed that the DNA phenotypes of the Acanthamoeba organisms were identical to those of the Ma strain in two patients and to the Castellani strain in one patient.

Acanthamoeba↗

Detection of methicillin-resistant Staphylococcus aureus in donor eye preservation media by polymerase chain reaction.

To examine contamination of donor eye preservation media with methicillin-resistant Staphylococcus aureus (MRSA), we studied the media to detect specific genes for MRSA by use of the polymerase chain reaction (PCR) method. The materials were 36 samples of donor eye preservation media (EP-II) in which donor eyes had been stored for keratoplasty. Polymerase chain reaction procedures were carried out to simultaneously detect the spa gene, which codes protein A of S. aureus, and the mecA gene, which codes penicillin-binding protein-2' contributing resistance to methicillin. Along with PCR analyses, the preservation media was examined by conventional culture methods to determine bacteriologic contamination. The PCR analyses of the 36 samples revealed that both the spa and the mecA genes were positive in five samples, only the spa gene was positive in two, and only the mecA gene was positive in two. The conventional culture of the media showed positive for MRSA in 5 samples, methicillin-susceptible S. aureus (MSSA) in 2, methicillin-susceptible coagulase-negative staphylococci (MS-CNS) in 4, and methicillin-resistant coagulase-negative staphylococci (MR-CNS) in 2 of the 36 samples. The results of PCR coincided well with those of conventional bacteriologic culture. Polymerase chain reaction analysis for spa and mecA genes is useful in detecting contamination of donor eye preservation media by MRSA, MSSA, MR-CNS, or MS-CNS in a shorter time than by conventional culture.

Adult↗

Long-term follow-up of excimer laser phototherapeutic keratectomy.

PURPOSE: To evaluate long-term follow-up results of excimer laser phototherapeutic keratectomy (PTK) in a Japanese population. METHODS: Twenty-six patients (31 eyes) with corneal opacity were treated with excimer laser PTK. Preoperative diagnoses included 16 eyes with band keratopathy, 10 with granular dystrophy, and 5 with corneal scar. Mean postoperative follow-up was 27 months. RESULTS: Corneal opacity was reduced in all patients. At postoperative month 12, best spectacle-corrected visual acuity (BSCVA) improved from the preoperative level in 22 eyes of 28 eyes, did not change in 3 eyes, and declined in 3 eyes. BSCVA at month 24 was better than the preoperative acuity in 17 eyes of 23 eyes, similar in 1 eye, and worse in 5 eyes. Eyes with granular dystrophy showed significantly better BSCVA improvement than those with band keratopathy. A hyperopic shift of +1.0 diopter or more occurred in 14 eyes of 28 eyes at month 12 and in 12 eyes of 23 eyes at month 24. No serious adverse effects were encountered during the 3-year follow-up period. CONCLUSIONS: Excimer laser PTK is a safe and effective procedure for the treatment of Japanese patients with superficial corneal opacity.

Adult↗

A 10-year review of penetrating keratoplasty.

PURPOSE: To survey the changes in indications for penetrating keratoplasty (PKP) and re-evaluate the risk factors for allograft rejection and graft failure. METHODS: We evaluated the records of 396 eyes of 335 patients who had undergone PKP at the Tokyo University Hospital between 1987 and 1997. Clinical results were analyzed by the Kaplan-Meier life table method and the log-rank test. RESULTS: The overall rates of graft survival and rejection-free graft survival at 10 years were 72.2% and 76.8%, respectively. The rates of graft survival and rejection-free graft survival were 98.8% and 86.6% in keratoconus, 87.0% and 56.5% in herpetic keratitis, 76.9% and 73.1% in corneal dystrophy and degeneration, 69.4% and 80.6% in nonherpetic keratitis, 62.5% and 75.0% in chemical burns, 61.8% and 72.1% in regrafting, and 51.1% and 79.8% in bullous keratopathy, respectively. The graft survival rates were statistically higher in the PKP alone group than in the combined operation group. The graft survival and rejection-free graft survival rates were statistically higher in the first operation group than in the regrafted group, and in the avascular cornea group than in the vascular cornea group. CONCLUSIONS: We recognized changes in indications for PKP. Combined operation, reoperation, and vascularization of recipient cornea were risk factors for graft failure.

Adolescent↗

Long-term effects of topical cyclosporine A treatment after penetrating keratoplasty.

PURPOSE: To evaluate the long-term outcome of topical 2% cyclosporine A (CsA) treatment as an adjunct to topical corticosteroid treatment of patients after penetrating keratoplasty (PKP). METHODS: We reviewed the records of 83 patients (86 eyes) who had undergone PKP and received topical CsA treatment postoperatively; also the records of 95 PKP patients (97 eyes) who received the same treatment, except for the 2% CsA eyedrops, and served as controls. The patients were also subdivided into high-risk and low-risk groups. The clinical outcome of PKP was evaluated by the rates of graft survival and rejection-free graft survival, using the Kaplan-Meier method, and compared with the log-rank test. RESULTS: In the high-risk patients, the rejection-free graft survival rate was 69.7% in the CsA group and 45.4% in the control group (P =.030), but there was no significant difference in the graft survival rate between the two groups. CONCLUSION: Topical cyclosporine treatment is effective in reducing the risk of allograft rejection in high-risk patients.

Corneal Diseases↗

MR findings of hypoxic damage of the bilateral striate cortices: a case report.

MR imaging of a patient with cortical blindness revealed areas of abnormal signal bilaterally in the lateral putamen and the striate cortices. The coronal T2-weighted image clearly demonstrated the selective involvement of the bilateral striate cortices. The differential diagnosis and the vulnerability of the striate cortex are discussed.

Accidents, Traffic↗

Vitamin K deficiency and osteopenia in disuse-affected limbs of vitamin D-deficient elderly stroke patients.

Bone mineral density is reduced in stroke patients on the hemiplegic and contralateral sides, reflecting a degree of paralysis and vitamin D deficiency. Because the deficiency of vitamin K, a factor essential for site-specific carboxylation of bone Gla protein, is also associated with reduced bone mineral density, an additional contribution of vitamin K to bone changes was assessed in 168 elderly patients with long-standing post-stroke hemiplegia and hypovitaminosis D. Sera were analyzed to relate vitamin K1 concentrations to bone-related biochemical indexes and bone mineral density measured by radiodensitometry of the second metacarpal. Bone mineral density was lower on both sides in patients than in the 56 controls (P < 0.02). Serum vitamin K1 concentrations, which correlated positively with bone Gla protein concentrations (P < 0.0001), were lower in patients (0.48 +/- 0.47 nmol/L) than controls (1.33 +/- 0.49; P < 0.0001). Serum bone Gla protein and 25-hydroxyvitamin D concentrations were lower in patients than controls (P < 0.0001), whereas ionized Ca concentrations were higher in patients (1.277 +/- 0.041 mmol/L) than controls (1.210 +/- 0.049; P < 0.0001), correlating with the Barthel index. Multivariate linear regression identified vitamin K1, bone Gla protein, 25-hydroxyvitamin D, ionized calcium, and the Barthel index as independent bone mineral density determinants on the hemiplegic side and 25-hydroxyvitamin D, calcium, and the Barthel index on the intact side. Immobilization and vitamin K deficiency had stronger osteopenic effects on the hemiplegic side than contralaterally.

Aged↗