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T Fukuchi

Publications and source records attributed to T Fukuchi.

At least 19 recordsLinked to original sources
PubMed2001

Optical coherence tomography (OCT) findings in normal retina and laser-induced choroidal neovascularization in rats.

BACKGROUND: To evaluate the optical coherence tomographic (OCT) features of the retina of rats, we compared the OCT images with the histological appearance of normal retinas and retinas with laser-induced choroidal neovascularization. METHODS: Twelve eyes of 12 adult pigmented rats (Brown-Norway) were used. Color fundus photography, fluorescein angiography (FAG), and OCT images of normal retinas and retinas with laser photocoagulation-induced choroidal neovascularization were studied. RESULTS: OCT showed a double-layered structure in the normal sensory retina with a highly reflective layer located in the inner retina and a low reflective layer located in the outer retina. The retinal pigment epithelium (RPE) and choriocapillaris were imaged as a layer with the highest reflection. On the first day after photocoagulation, OCT showed a disruption of the highly reflective layer corresponding to the RPE, and an enhanced reflectivity in the choroid under the lesion. Choroidal neovascularizations (CNVs) which appeared 2 weeks after photocoagulation was seen as a multi-layered, highly reflective area protruding from the RPE into the subretinal space A CNV beneath a subretinal hematoma was difficult to detect because of the low transmission of the scanning light through the hematoma. The histopathological appearance was well correlated with the OCT images. CONCLUSION: The two reflective bands in the OCT images were identified as coming from the inner layers of the retina and from the photoreceptors. The highest reflective band arose from the RPE and choriocapillaris. In the future, OCT combined with FAG or indocyanine-green angiography will be a useful tool for the evaluation of animal studies of choroidal neovascularization and other retinal diseases.

Animals↗
PubMed2001

Staging of idiopathic choroidal neovascularization by optical coherence tomography.

PURPOSE: To assess the clinical course of idiopathic choroidal neovascularization (ICNV) by optical coherence tomography (OCT). METHODS: Thirty-two patients with a clinical diagnosis of ICNV were examined between December 1995 and October 1999. The ages of the patients ranged from 18 to 53 (mean 35.9) years, and the mean period of observation was 5.8 months. Color fundus photography, fluorescein angiography, Indocyanine green angiography, and OCT were performed. The stage of the ICNV was classified as active, intermediate, or cicatricial, based on past history, fundus findings, and fluorescein angiography (FAG). The characteristic OCT images at these three stages were determined. RESULTS: OCT revealed that there were characteristic tomographic images of the choroidal neovascularization (CNV) at each stage. In the active stage, OCT revealed the CNV as a highly reflective, multi-layered area protruding into the subretinal space. In the intermediate stage, the reflectivity of the CNV became stronger and its margin in the subretinal space became smooth. With regression of the ICNV, the lesions consisted of two different areas: a most reflective area corresponding to the fibrotic changes of the CNV (imaged white in OCT images), and a reddish highly reflective area representing a compound protrusion of the CNV. In the cicatricial stage, the ICNV was observed as a moderately high reflective area covered by a dome-shaped highly reflective layer corresponding to the retinal pigment epithelium. CONCLUSION: These findings demonstrated clearly the changes in the OCT images during the development and regression of ICNV. OCT was useful for following the clinical course and understanding the mechanism of the CNV regression.

Adolescent↗
PubMed2001

[An ultrasound biomicroscopic study of eyes after non-penetrating trabeculectomy].

PURPOSES: We studied the control of intraocular pressure(IOP) by various types of blebs after non-penetrating trabeculectomy(NPT) and the difference between bleb formation after penetrating trabeculectomy(PT) and that after NPT. METHODS: The filtering blebs of 45 yeys from 40 patients after NPT were studied using ultrasound biomicroscopy. They were grouped into four types, and the space under the scleral flap was classified into three types. The filtering blebs and the space under the scleral flap were correlated with IOP level. RESULTS: Overall, 40% of the blebs were L(low-reflective) type, 16% H(high-reflective) type, 16% E (encapsulated) type, and 29% F(flattened) type, but in good IOP control cases 59% of the blebs were L type, 14% H type, 14% E type, and 14% F type. L type blebs were found in 94% of eyes with good IOP control. CONCLUSION: Though filtering blebs of the L type could produce sufficient IOP reduction, blebs after NPT showed a greater tendency to become flattened than after PT. Additional systematic therapy must be designed to maintain the L type of filtering blebs after NPT.

Glaucoma↗
PubMed2001

[Persistent hyperplastic primary vitreous--a case report of adult onset acute angle-closure glaucoma].

BACKGROUND: We report a patient with persistent hyperplastic primary vitreous(PHPV) who presented with acute angle-closure glaucoma in his adult life. CASE: A 30-year-old man had an attack of acute angle-closure glaucoma associated with retrolenticular fibrous tissue, atrophic retina, and elongated cilliary process in his right eye. RESULT: Ultrasound biomicroscopy(UBM) study showed iris bowing, shallow anterior chamber, and elongated cilliary body which were being pulled by the retrolenticular mass. The posterior chamber was normal. CONCLUSION: Although the mechanisms of secondary angle-closure glaucoma in PHPV are complicated, we suspected pupillary block resulting from constriction by the retrolenticular mass in this case.

Acute Disease↗
PubMed2000

Effects of portal-systemic shunt following 90% partial hepatectomy in rats.

We studied the effects of portal-systemic shunt after massive hepatectomy. Male Wistar rats were divided into two groups: one group underwent laparotomy alone (C group) and in the other group a portal-systemic shunt was placed through laparotomy (S group). After 90% hepatectomy was performed, 3-day and 1-week survival rates and histopathology were examined, and hepatic hemodynamics during the early stage after hepatectomy were measured using dye-containing microspheres. The 3-day survival rate in the S group was significantly higher, and the 1-week survival rate was slightly higher, than those in C group. Sinusoidal dilation 7 days after hepatectomy in the S group was significantly milder than that in the C group. Fatty degeneration of hepatocytes in the S group was significantly milder than that in the C group. With respect to hepatic hemodynamics during the early stage after hepatectomy, the rate of shunt (26.3%) in the S group was significantly higher than that (9.5%) in the C group. Portal pressure, total hepatic blood flow, and total hepatic blood flow per gram of liver in the S group were significantly lower than those in the C group. These results suggest that approximately 26% shunt after 90% hepatectomy in rats increases the early survival rate and improves histological changes in surviving rats 7 days after resection.

Animals↗
PubMed2000

Ultrastructural localization of myocilin in human trabecular meshwork cells and tissues.

We examined ultrastructurally the localization of myocilin (formerly called trabecular meshwork inducible glucocorticoid response, or TIGR) protein in cultured human trabecular meshwork (TM) cells and in normal human TM tissues. The TM, a specialized tissue located at the chamber angle of the eye, is believed to be responsible for the development of glaucoma. The myocilin gene has been directly linked to both juvenile and primary open-angle glaucomas, and multiple mutations have been identified. Human TM cells were treated with 0.1 mM of dexamethasone (DEX) to induce myocilin expression. This protein was immunolocalized by colloidal gold electron microscopy using an anti-human myocilin polyclonal antibody. Double labeling with different sizes of gold particles was also performed with additional monoclonal antibodies specific for cell organelles and structures. In both DEX-treated and untreated cultured cells, myocilin was associated with mitochondria, cytoplasmic filaments, and vesicles. In TM tissues, myocilin was localized to mitochondria and cytoplasmic filaments of TM cells, elastic-like fibers in trabecular beams, and extracellular matrices in the juxtacanalicular region. These results indicate that myocilin is localized both intracellularly and extracellularly at multiple sites. This protein may exert diverse biological functions at different sites.

Adult↗
PubMed2000

Pharmacokinetics and metabolism of 123I-BMIPP fatty acid analog in healthy and CD36-deficient subjects.

UNLABELLED: Some have suggested that CD36, which is a multifunctional receptor with a molecular weight of 88 kDa, functions as a long-chain fatty acid (LCFA) transporter. We recently reported on a complete myocardial accumulation defect of the radiolabeled LCFA analog (123)I-15-(p-iodophenyl)-(R,S)-methylpentadecanoic acid (BMIPP) in patients with CD36 deficiency. In this study, we investigated the pharmacokinetics of BMIPP in patients with a myocardial accumulation defect of BMIPP accompanied by CD36 deficiency. METHODS: Five patients (3 men, 2 women) with CD36 deficiency and 3 healthy men were investigated. Serial myocardial images were obtained every 70 s for 20 min (dynamic acquisition) and at 30, 60, 120, 180, and 240 min (static acquisition) after an intravenous bolus injection of 148 MBq BMIPP. Whole-body imaging was performed 60 min after injection. Plasma levels of BMIPP and its final metabolite, piodophenylacetic acid, at 2, 5, 10, 30, 60, 120, and 240 min after administration were determined. RESULTS: In the CD36-deficient patients, myocardial images could not be obtained for up to 240 min after administration, and cardiac pool images showing only the cardiac chambers were obtained. The heart-to-mediastinum ratio was significantly lower in the CD36-deficient patients than in the healthy volunteers (1.71 +/- 0.11 versus 2.95 +/- 0.22, P < 0.05). Hepatic uptake of BMIPP was nearly double in CD36-deficient patients. The elimination of BMIPP from the circulation was retarded in the CD36-deficient patients. CONCLUSION: We suggest that CD36 deficiency leads to decreased myocardial accumulation of BMIPP and retardation of BMIPP elimination from the circulation. The accumulation defect is probably caused by a defect in LCFA uptake into the myocardium through CD36.

Adult↗
PubMed2000

[Collagen fibrils in nanophthalmic sclerae].

PURPOSE: To examine collagen fibrils in 3 nanophthalmos sclerae and to compare them with normal control sclerae morphometrically. MATERIALS AND METHODS: Three cases of nanophthalmos associated with uveal effusion were studied. When sclerectomy was performed, scleral specimens were collected and fixed with 3% glutaraldehyde/2.5% paraformaldehyde. After epon-embedding and ultrathin sectioning, they were examined by transmission electron microscopy. Collagen fibrils from both nanophthalmos and normal control sclerae were compared in diameters and numbers per micron 2 areas. RESULTS: All scleral tissues from the three cases were associated with irregularly woven and unclear collagen bundles. Several abnormal findings, such as twisting or fraying, were also detected in a few collagen fibrils. The diameter and density of normal-appearing collagen fibrils that occupied most areas of nanophthalmos sclerae were the same as those from normal control sclerae morphometrically. CONCLUSIONS: Although nanophthalmos sclerae even with uveal effusion showed thick irregular collagen bundles and a few abnormal collagen fibrils, most collagen fibrils appeared the same as normal controls.

Adult↗
PubMed1999

Detection of endometrial cancer by flow cytometry using two monoclonal antibodies.

BACKGROUND: To develop a supplementary diagnostic method for endometrial cancer by measuring the reactivity of various endometrial lesions with two monoclonal antibodies. METHODS: We investigated the reactivity of various endometrial lesions with two monoclonal antibodies (MSN-1 and MSN-3) by flow cytometry (one-color and two-color methods). RESULTS: The two-color method appeared to be suitable for use in place of simultaneous performance of the one-color methods with MSN-1 and MSN-3. The positivity rate for normal endometrium was 16.0% with the two-color method, which was lower than the rate of 30.0% obtained with concomitant used of the one-color methods. The positivity rate for endometrial cancer was high, 84.0%, with the two-color method. The positivity rate was 85.7% for well-differentiated endometrial cancer, 71.4% for moderately differentiated cancer, and 100.0% for poorly differentiated cancer; thus, the rate was high irrespective of the cellular differentiation. CONCLUSIONS: The two-color method is more useful than the one-color method as a supplementary diagnostic procedure for endometrial cancer.

Antibodies, Neoplasm↗
PubMed1999

Three-dimensional appearance of Bowman's layer after radial keratotomy.

PURPOSE: To examine the 3-dimensional collagen fibrillar architecture of Bowman's layer after radial keratotomy (RK). SETTING: Department of Ophthalmology, Niigata University School of Medicine, Niigata, Japan. METHODS: This study used monkey eyes in which 0.3 mm deep radial incisions were made on the cornea 2 weeks and 1, 6, and 12 months before the animals were killed. Corneal buttons were immersed in a fixative and the cells macerated with sodium hydroxide 10%. Scanning electron microscopy (SEM) was performed according to standard procedures. A part of the specimens was embedded in epoxy resin for light microscopic (LM) observation for comparison. RESULTS: The 3-dimensional collagen fibrillar architecture of Bowman's layer was revealed by SEM. The rupture of Bowman's layer could be seen 12 months after surgery and there was no continuity of collagen fibrils in the ruptured area. In LM observations, the width of the stromal incisions gradually became narrower near 12 months after surgery. CONCLUSION: Our cell-maceration/SEM method showed that the rupture of Bowman's layer remained up to 12 months after RK. This suggests that discontinuity of Bowman's layer may be responsible for globe rupture after RK.

Animals↗
PubMed1999

Collagen fibrillar network in the optic nerve head of normal monkey eyes and monkey eyes with laser-induced glaucoma--a scanning electron microscopic study.

PURPOSE: To examine the three-dimensional organization of collagen fibrils in the lamina cribrosa of normal monkey eyes and monkey eyes with laser-induced glaucoma. METHODS: Intraocular pressure elevation and glaucomatous optic discs were obtained in one eye of three adult monkeys by repeated applications of argon laser to the chamber angle. The monkey eyes were enucleated, and the collagen fibrillar network was investigated by scanning electron microscopy after cell maceration with 10% sodium hydroxide and conductive staining. RESULTS: In normal monkey eyes, round to oval shaped regular laminar pores through which axon bundles exited were observed in the lamina cribrosa. The straight, column-like pores or openings were formed by multilayered laminar plates that aligned vertically in parallel with the optic nerves. The surface of the laminar plates was covered by delicate, loosely arranged collagen fibrils. The inner surface of the pores was smooth, made up of well-packed collagen fibers. In glaucomatous eyes, the laminar pores were clogged by tightened collagen fibrils. The inner surface of the pores was irregular, and the pores were narrowed or distorted. CONCLUSIONS: Alterations in the three-dimensional organization of collagen fibrils were demonstrated in the optic nerve head of glaucomatous monkey eyes. The architectural changes may affect the flexibility and resilience required of the lamina cribrosa in supporting optic nerve fibers.

Animals↗
PubMed1999

Changes of beta-1,4-galactosyltransferase with the development of endometrial cancer.

To elucidate the mechanism of the type 2 carbohydrate chain accompanying the development of endometrial cancer, we studied the expression of beta-1,4-galactosyltransferase (beta-1,4GT) in normal endometrial and endometrial cancer tissues. An immunohistochemical study revealed that beta-1,4GT was diffusely positive in the cytoplasm of endometrial cancer cells, and that the level of its expression was increased compared with that in normal endometrium. Also, beta-1,4GT mRNA corresponding to 4.7 kb was very low in normal endometrium, while an intense signal was detected in endometrial cancer. Our results suggest that the increase of beta-1,4GT contributes to the expression of the type 2 carbohydrate chain in endometrial cancer.

Endometrial Neoplasms↗
PubMed1999

[Changes in transforming growth factor-beta and platelet-derived growth factor in the optic nerve head in monkey experimental glaucoma].

PURPOSE: Remodeling of the extracellular matrix occurs in the lamina cribrosa in progressed glaucomatous optic nerve damage including disc cupping. We examined immunohistochemical changes in the transforming growth factor (TGF)-beta and platelet derived growth factor (PDGF) in the optic nerve heads in experimentally induced glaucoma. METHODS: We used 3 cynomolgus and 2 Japanese monkey eyes. Glaucoma was induced by repeated argon laser photocoagulation of the chamber angle. Eyes were enucleated after disc cupping had formed 3 to 5 months after treatment. The optic nerve head was examined for expression of TGF beta 1, beta 2, and beta 3, and PDGF A and B in frozen sections and by the biotin-ExtrAvidin-Alkali Phosphatase method. FINDINGS: Normal monkey eyes showed TGF beta 1, beta 2, and beta 3, and PDGF A, and B in the optic nerve head including the nerve fibers, glial cells, and vascular cells. Glaucomatous eyes showed stronger expression of TGF beta 1 and beta 2 in the glial cells around the lamina cribrosa. The staining intensities for TGF beta 3, PDGF A, and PDGF B were the same as in normal eyes. CONCLUSION: Eyes with experimental glaucoma showed higher expressions of TGF beta 1 and beta 2 around the lamina cribrosa. This finding may show upregulation of extracellular matrix production as related to remodeling of the lamina cribrosa in glaucoma.

Animals↗
PubMed1999

[CA546, CA602].

Explore the source record for details and available documents.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1999

[Studies on brain pyruvate dehydrogenase (PDH) activity and energy metabolites during ischemia and reperfusion].

Pyruvate dehydrogenase is one of the mitochondrial enzymes considered important in the regulation of oxidative metabolism. To further understand the relationship between its activity and ischemic brain damage we conducted three experiments. We studied the effects of (1) duration of cerebral ischemia, (2) the Ca2+ channel blocker, nicardipine, and (3) the immunosuppressant, FK506, on PDH activity and energy metabolites during ischemia and reperfusion. In the first study we also measured regional cerebral blood flow (rCBF). (1) Increasing the duration of the ischemic insult delayed the deactivation of PDH, slowed the resynthesis of high energy phosphates and the clearance of lactate, and impaired recovery of rCBF. Additionally, (2) nicardipine normalized PDH activities and improved the impaired metabolism after reperfusion, and (3) FK506 did not effect PDH activity, but significantly improved the impaired metabolism during the early phase of reperfusion. From these studies we conclude that PDH plays a role in the recovery of metabolism during reperfusion, and both nicardipine and FK506 improve metabolism during the early phase of reperfusion.

Animals↗