Biomedical subjects

T Fukuchi

Publications and source records attributed to T Fukuchi.

At least 73 records · Page 4Linked to original sources

PubMed1993

Age-related changes of sulfated proteoglycans in the human lamina cribrosa.

Sulfated proteoglycans in the lamina cribrosa of the optic nerve head from individuals aged 2 months, 18 months, and 23, 35, 44, 55, 67, 74, and 88 years were studied by electron microscopy after cuprolinic blue dye binding. Within the cores of the laminar plates, cuprolinic blue-positive chondroitin/dermatan sulfate proteoglycan filaments of different sizes were found associated with collagen fibers. In addition, small punctate and filamentous structures that represented heparan sulfate proteoglycan molecules were associated with the basal laminae of astrocytes and blood vessels. In the eyes of older individuals, the chondroitin/dermatan sulfate and heparan sulfate proteoglycan filaments were found to be shorter than those in younger persons. A mild decline with aging in the diameter of the filaments was also noted. Our findings illustrate the age-related changes in the proteoglycans in the human lamina cribrosa, which may help explain why the optic nerve head is more susceptible to damage with aging.

Adult↗

PubMed1993

[Intravascular ultrasound imaging on the endarterectomized coronary arteries in two patients].

Intravascular ultrasound imaging on the endarterectomized coronary arteries in two patients are reported with a review of the literature. Case 1, a 62-year-old male and case 2, a 64-year-old male underwent endarterectomy of the right coronary artery (#3--#4PD, 4AV) combined with coronary arterial bypass grafting. Coronary arteriography (CAG) and intravascular ultrasound imaging (IVUS) were performed one month after operation. CAG revealed bypass grafts and endarterectomized coronary arteries to be patent together, and IVUS revealed endarterectomized coronary arteries had two layers, outer layer to be hyperechoic and inner layer to be heterogenously echoic in both cases. The histological examination of specimens suggests this heterogenously echoic area represents media, thrombus and irregularly proliferated intima. Therefore, anticoagulant therapy after endarterectomy should be strictly performed.

Coronary Artery Bypass↗

PubMed1993

[Histopathology of corneal plaque in vernal keratoconjunctivitis].

The author reported 2 cases of vernal keratoconjunctivitis with corneal plaque showing a white board-like appearance. Conventional medications were not effective in both cases and during the course of the disease corneal ulcer developed followed by formation of corneal plaque. After the plaque spontaneously peeled off, or were surgically removed, the ulcers of both cases healed. The histological specimens from the 2 cases were examined by light and electron microscopy. The plaques showed lamellae-like structures, and formed alternate accumulation of hyaline-like material and another amorphous material. No cell components, such as corneal epithelial cells, keratocytes, or fibroblasts, were found either on the surface of and within the plaques. The corneal epithelial cells and/or eosinophils, however, were found at the edge of the plaque. These findings may suggest that these corneal plaques were formed by repeated episodes of deposition and that corneal epithelial cells and eosinophils may have been involved.

Adolescent↗

PubMed1993

[Proteoglycan abnormality in a nanophthalmos sclera].

We examined a scleral specimen obtained from a nanophthalmos eye with uveal effusion at the surgery, using cuprolinic blue (CB) dye binding and electron microscopy. The nanophthalmic sclera was separated into two areas electron microscopically. One was an area composed of tightly packed collagen fibers, the other with irregularly arranged collagen fibers. In irregular areas, several abnormal findings, such as twisting or fraying, were detected in collagen fibers, which were surrounded by fine fibrous materials. Furthermore, CB-positive materials were fewer in number and less in size and electron density around the collagen fibers and in fine fibrous materials than in the normal eye. Since the nanophthalmic sclera in this study showed some abnormalities both in collagen fibers and in proteoglycans, we suggest that the function and/or interaction of both of these were abnormal, which might be related to the onset of uveal effusion.

Adult↗

PubMed1993

[Emergency operation for complete papillary muscle rupture after myocardial infarction--a case report of 81-year-old patient].

Mitral regurgitation due to complete rupture of the papillary muscles after myocardial infarction has a very poor prognosis, even if diagnosed and operated on at an early phase. Recently, we performed an emergency operation for mitral regurgitation due to complete papillary muscle rupture after myocardial infarction in an 81-year-old patient. This is probably the oldest case in Japan. Operation revealed complete rupture of the posterior papillary muscle, and valve replacement with a Carpentier-Edwards bioprosthesis was performed.

Aged↗

PubMed1992

Extracellular matrix changes of the optic nerve lamina cribrosa in monkey eyes with experimentally chronic glaucoma.

Using light microscopic immunohistochemistry, we studied the immunolocalization and immunoreactivity of the extracellular matrix, including collagen types III, IV, VI, laminin, and alpha elastin in the lamina cribrosa of monkey eyes with normal and experimentally chronic glaucoma. Our results showed: (1) abnormal linearlike immunodeposits of both collagen type IV and laminin in the margin of the lamina cribrosa with significant density in the glaucomatous eyes; (2) the immunoreactivity of collagen type III resembled that of the normal eye, but was slightly stronger at the laminar surface; (3) findings with collagen type VI resembled those of type III with an enhanced linearlike staining surrounding the nerve-fiber bundles. Furthermore, staining of alpha elastin demonstrated dramatic changes in both reactivity and localization. The lamina cribrosa of glaucomatous eyes showed a markedly reduced immunoreactivity as well as an irregular, interrupted pattern. These observations suggest that the changes might be a secondary to the long-standing elevation of intraocular pressure. The alteration of these macromolecules may modify the course of glaucomatous optic damage.

Animals↗

PubMed1992

[A case of acute right ventricular infarction and life-saving right ventricular assistance following emergency coronary revascularization and resection of a left ventricular aneurysm--discussion of indication and proper assist flow volume].

Right ventricular assistance (RVA) using centrifugal pump in combination with IABP was used to treat a patient who was difficult to wean from a cardiopulmonary bypass following emergency coronary revascularization and resection of a ventricular aneurysm performed to treat acute right ventricular infarction due to a PTCA complication. After 131 hours of RVA at 3.2 to 4.8 l/min, it was possible to remove the pump. No heparin was administered during this time, changing the pump head twice, was used for 64 and 50 hour period, no thrombi were detected either time. After being weaned from RVA, the patient developed severe respiratory dysfunction, but on the 10th postoperative day (POD) IABP was weaned, and on the 13th POD the artificial respirator was withdrawn. The results of the postoperative cardiac catheterization were favorable, the patient was discharged on the 57th POD, and has returned to society at the present time. The indications for RVA include a central venous pressure > 20 mmHg and a cardiac index < 1.8 l/min/m2, and tissue perfusion pressure and general preoperative condition should severe as guides. The higher the assisted flow volume the more efficacious in relieving ventricular load, but, since there is a limit to how much the left ventricle and lungs can withstand, it should not exceed levels which ensure the maintainance of cardiac output and tissue perfusion pressure.

Angioplasty, Balloon, Coronary↗

PubMed1992

[Changes in sulfated proteoglycans in alkali injured rabbit cornea].

Morphological changes of sulfated proteoglycans (S-PGs) in the stroma of alkali injured rabbit corneas were examined electron-histochemically following cuprolinic blue (CB) dye binding. The injured eyes were followed for 2 months by slitlamp microscope and photographs. At 1 hour, 3 days, 1 week, 2 weeks, 1 month, and 2 months after the injury, the eyes were enucleated and studied. After 1 hour, while both collagen fibrils and the filaments of S-PGs had already become disarranged; the number of S-PGs appeared to decrease. From 3 days to 1 week after, the number as well as the electron-density of S-PGs were markedly decreased in all areas. After 2 weeks, CB-positive large filaments appeared in anterior stroma. These became larger, more abnormal in shape, and displayed a higher electron density 1 month later. Normally arranged S-PGs can be seen at 2 months later. It was concluded that S-PGs were diminished in alkali-injured corneas. Once they were replaced by abnormal filaments, they gradually recovered normal morphology. Further more the time course of S-PG change correlated with that of corneal transparency after alkali injury.

Animals↗

PubMed1992

[Experience of intravascular ultrasound imaging on a stenosed saphenous vein graft].

A 73-year-old man underwent coronary-artery bypass grafting surgery on #4 PD and #7 with saphenous vein graft. Coronary arteriography and graft visualization performed on the 28th postoperative day revealed 75% concentric stenosis in the middle of the #4 PD graft. Before and after PTCA to the graft, examination by intravascular ultrasound imaging was performed and revealed that the stenosis was caused by fibrotic atheroma or thrombus. Intravascular ultrasound imaging appears to be useful in the field of cardiac surgery. It can be used in the follow-up of bypass grafts and also the detection of the entry site in dissecting aortic aneurysms. A brief review of the literature is given.

Aged↗

PubMed1992

Sulfated proteoglycans in the human lamina cribrosa.

The sulfated proteoglycans in the normal human lamina cribrosa were studied by electron microscopy after cuprolinic blue dye binding. Within the cores of the laminar plates, three types of cuprolinic blue-positive proteoglycan filaments with different sizes were associated with collagen fibers. These filaments, which were partially sensitive to chondroitinase AC and chondroitinase B, were completely removed by chondroitinase ABC and were identified as chondroitin/dermatan sulfate proteoglycans. In addition, small punctate and filamentous structures that stained with cuprolinic blue were associated with the basal laminae of astrocytes and blood vessels. Enzyme chondroitinase ABC had no effect, but heparinase digested all of these basement membrane-associated structures, indicating that they represented heparan sulfate proteoglycan molecules. Keratanase did not affect any of the cuprolinic blue-positive materials. This investigation illustrates the ultrastructural distribution and morphology of proteoglycans in the human lamina cribrosa and provides baseline information for future studies regarding the roles of proteoglycan molecules in diseases such as glaucoma.

Aged↗

PubMed1991

Possible involvement of free radicals and antioxidants in the early stages of the development of cardiomyopathy in BIO 14.6 Syrian Hamster.

The BIO 14.6 cardiomyopathic Syrian hamster is a well-known animal model of congestive cardiomyopathy. To evaluate the role of free radicals and antioxidant protection in the pathogenesis of cardiomyopathy in this animal, we studied the concentration of heart mitochondrial free radicals, the activities of glutathione peroxidase (GSHPx) and superoxide dismutase (SOD), and the effect of alpha-tocopherol on the early stage of myocardial damage (up to 90 days). The GSHPx activity in BIO 14.6 hamsters was found to be twice that in the normal control hamsters at 30 days of age, while SOD activity was unchanged at 30 and 90 days of age. The concentrations of mitochondrial free radicals in BIO 14.6 hamsters at 40 and 90 days of age were significantly higher than those in the normal control hamsters. A protective effect of alpha-tocopherol therapy was shown in BIO 14.6 hamsters treated during the early stage of cardiomyopathy (up to 90 days). These results show the role of free radicals and antioxidant protection in the pathogenesis of hamster cardiomyopathy. We suspect that an increase in the GSHPx activity in BIO 14.6 hamsters may be due to a compensatory mechanism to counteract oxidative stress, but antioxidant reserve was not sufficient to protect the heart from the toxic effects of increased free radicals in the early stage of cardiomyopathy.

Animals↗

PubMed1991

[Operative management of the calcified patent ductus arteriosus in the elderly].

Two cases of the calcified PDA were experienced in subjects aged more than 50 years. A 63-year-old woman was successfully operated upon. A Fogarty's balloon catheter was wedged into the PDA through the ductus after a pulmonary arteriotomy under cardiopulmonary (CP) bypass. A 57-year-old woman was safely operated. PDA was repaired under partial CP bypass with Bio-pump. Postoperative courses of these cases were uneventful. Brief review of surgical treatment for PDA was given.

Calcinosis↗

PubMed1991

[Extracellular matrix of the optic nerve lamina cribrosa in monkey eyes with experimentally induced glaucoma].

The changes of immunoreactivity and immunolocalization of the extracellular matrices (ECM), collagen type I through VI, laminin, fibronectin and alpha-elastin, of optic nerve lamina cribrosa in argon laser induced glaucoma in monkey eyes were examined using a immunohistochemical method, biotin-streptavidin system. The results were consistent with the previous findings that in the experimental glaucoma eyes, diffuse immunoreactivity of collagen type I, III, V, VI, fibronectin were detected in the thickened and irregular laminar beams, while linear staining for collagen type IV and laminin were seen around the laminar beams and vascular walls were densely, thickly and irregularly, and furthermore immunoreactivity for alpha-elastin was reduced markedly in the glial columns and moderately in the lamina cribrosa. In the lamina cribrosa with optic disc cupping in laser-induced monkey glaucoma, the immunoreactivity for alpha-elastin was changed most greatly, and no qualitative differences were detected in comparison with normal fellow eyes for the other ECM components.

Animals↗

PubMed1990

Long-term efficacy of low power argon laser trabeculoplasty.

We studied the long-term efficacy of argon laser trabeculoplasty, applying low-power (a mean of 450 mW), a duration of 0.1 second, and a small number of burns (a mean total energy of 1.85 J) over 90 to 120 degrees of the trabecular meshwork. Fifty-four eyes with poorly controlled open-angle glaucoma were treated. The mean follow-up was 46 months. The mean intraocular pressure decrease was 5.3 mmHg in 35 eyes at one year, 6.1 mmHg in 23 eyes at 3 years, 5.1 mmHg in 13 eyes at 5 years, and 5.4 mmHg in 5 eyes at 6 years. Life-table analysis showed that the probability of success was 58% at one year, 49% at 3 years, and 46% at 5 years. Both the incidence and magnitude of the intraocular pressure rise in the early post-laser period were minimal and no serious complications were observed.

Aged↗

PubMed1990

[Extracellular matrix of the optic nerve lamina cribrosa in the normal monkey eyes].

The presence and distribution of collagen type I through VI, laminin, fibronectin and alpha-elastin were demonstrated in the normal monkey optic nerve lamina cribrosa, using a immunohistochemical method, the biotin-streptavidin (B-SA) system. Interstitial collagens, collagen type I and III, were detected diffusely within laminar beams continuously with surrounding sclera. The adventitia around the central artery and vein, and pial septa were also stained with collagen type I and III. Collagen type IV and laminin, which were basement membrane materials, were localized linearly along the margin of the laminal beams, pial septa and adventitia. They were also stained in all vascular walls. Collagen type V, VI and fibronectin were similar with collagen type I and III, but their linear staining was more intense onto the margin of the laminar beams and the pial septa. Rich immunoreactivity for alpha-elastin was found in the glial columns and the laminal beams. The presence and distribution of the structural protein components of the ECM of the monkey optic nerve lamina cribrosa was the same as that previously reported in human.

Animals↗

PubMed1989

Patent ductus arteriosus with Eisenmenger's syndrome detected by first-pass study.

The case of a 20-year-old man with patent ductus arteriosus complicated with Eisenmenger's syndrome is described. Radionuclide angiocardiography characterized the abnormal pattern of blood flow through the central circulation to establish a diagnosis of patent ductus arteriosus with a significant right-to-left shunt, which had not been indicated by other clinical findings.

Adult↗

PubMed1989

[Optic disc measurements with computerized image analysis in experimental chronic glaucoma].

We quantitatively analyzed morphological changes of the optic disc of ten Japanese monkey eyes exposed to sustained intraocular pressure (IOP) elevation by repeated argon laser application to the trabecular meshwork. Using a computerized image analyzer (Topcon IMAGEnet), we measure the cup-disc ratio (CDR), disc area (DA), cup volume/disc area (CV/DA), and rim area/disc area (RA/DA). The duration of IOP elevation was 48.4 +/- 0.8 (mean +/- SD) weeks, and the mean IOP during the experiment was 26.3 +/- 2.6 mmHg [the mean IOP during the experiment/pre-treatment IOP was 2.05 +/- 0.55 (IOP ratio)]. In advanced glaucomatous eyes (the duration of IOP elevation of approximately one year), comparing pretreatment, the CV/DA increased 4.96 times, the vertical CDR increased 1.78 times, the horizontal CDR increased 1.69 times, the DA increased 1.42 times, and the RA/DA decreased 0.54 times. A significant positive correlation was found between the IOP ratio and, both the vertical CDR (gamma = 0.65) and the CV/DA (gamma = 0.68). These results suggested that the development of glaucomatous optic disc cupping correlated with the degree of IOP elevation in monkey eyes. Using this computer image analyser, the longitudinal quantitative follow-up of disc changes of experimental glaucoma may be useful for understanding the mode of human glaucomatous optic nerve damage.

Animals↗

PubMed1989

[Extracellular matrix of the human retrobulbar optic nerve].

The presence and distribution of laminin, fibronectin and type I through V collagens were determined in the human retrobulbar optic nerve using a immunohistochemical method, the biotin-streptavidin (B-SA) system. Type I and type III collagens, which were interstitial collagens, were detected diffusely within pial septa, pia mater, arachnoid membrane, dura mater and adventitia around the central retinal artery and vein. Type IV collagen and laminin, which were basement membrane materials, were localized linearly along the borders between optic nerve fascicles and pial septa, adventitia, pia mater. Also They were also stained in all vascular walls and the arachnoid membrane. Type V collagen and fibronectin were detected both in the interstitial connective tissues, diffusely, and in the basement membranes, linearly. Fibronectin was stained more intensively in the basement membranes than type V collagen.

Collagen↗