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Biomedical subjects

Y Kuwayama

Publications and source records attributed to Y Kuwayama.

At least 19 recordsLinked to original sources
PubMed2005

I kappa B-mediated apoptotic gene therapy against acute myelogenous leukemia using replication-defective HSV-1 vector expressing TK and mutant I kappa B alpha.

Overexpression of NF-kappa B reportedly plays anti-apoptotic roles in the growth of AML cells. Control of AML cell growth was attempted using a replication-defective herpes simplex virus-1 vector, T0I kappa B alpha, overexpressing mutant I kappa B alpha to inhibit NF-kappa B in vitro. T0I kappa B alpha displays defective ICP4/ICP22/ICP27, isogenic thymidine kinase, and mutant I kappa B alpha. T0Z.1 expressing lacZ instead of I kappa B was used for controls. Infection of T0I kappa B alpha at 15 multiplicity of infection (MOI) with cells of AML lines, HL60, K562, and NB4 displaying >90% infection efficiency and tumor killing in vitro. Use of 10 microM of Ara-C alone was clinically equivalent to high-dose Ara-C, displaying 11% tumor killing. Neither ganciclovir (GCV) nor Ara-C enhanced T0I kappa B- alpha mediated tumor killing. Attenuation of NF-kappa B by T0I kappa B alpha was confirmed by EMSA. T0I kappa B alpha induced caspase-3 activity, with subsequent apoptosis confirmed by colorimetric and TUNEL assays. Fresh AML cells from 8 patients were infected with T0I kappa B alpha at 3 MOI, with or without GCV or 10 microM of Ara-C in vitro. Infection efficiency was 10%. T0I kappa B alpha displayed 8-15% tumor killing, superior to Ara-C in 6 of the 8 patients. Administration of Ara-C enhanced tumor killing in 5 of these 6 cases. Our results suggest that T0I kappa B alpha-mediated gene therapy induces apoptosis of AML cells in vitro.

Adult↗
PubMed1999

[Observation of physiological change in the human ciliary body using an ultrasound biomicroscope during accommodation].

PURPOSE: To evaluate changes in the ciliary body during accommodation using an ultrasound biomicroscope (UBM). SUBJECTS AND METHODS: Eleven healthy persons, aged from 24 to 33 years, served as subjects. They were asked to lie in the supine position and to fixate a target placed on the ceiling 2 m above with the left eye. A concave lens with the power of -6 to -8 diopters was then placed before the fixating left eye. The thickness of the ciliary body in the right eye was measured by UBM in the nonaccommodative and accommodative states. FINDINGS: The anterior chamber in the right eye became significantly shallow during accommodation. The thickness of the ciliary body significantly increased during accommodation at 0.5 mm and 1.0 mm posterior to the scleral spur. It significantly decreased at 2.0 mm, 2.5 mm and 3.0 mm posterior to the scleral spur. CONCLUSION: During induced accommodation in the left eye, the anterior portion of the ciliary body in the right eye increased and the posterior portion decreased in thickness. The findings imply that the circular ciliary muscles are mainly involved in accommodation and not the longitudinal muscles.

Accommodation, Ocular↗
PubMed1999

[Clinical results of selective laser trabeculoplasty].

PURPOSE: Selective laser trabeculoplasty (SLT) is a new laser procedure using a frequency-doubled Q-switched Nd: YAG laser (wavelength: 532 mm). The laser parameters are set to selectively target pigmented trabecular meshwork (TM) cells without coagulative damage to the TM structure or non-pigmented cells. We investigated the safety and efficacy of SLT in lowering intraocular pressure (IOP). SUBJECTS AND METHOD: Sixty-seven eyes of 67 patients with uncontrolled open angle glaucoma were treated with the Coherent Selecta 7000 (Coherent Inc., Palo Alto, CA). Nineteen of 67 patients had previously received argon laser trabeculoplasty (ALT). A total of approximately 60 non-overlapping spots were placed over 180 degrees of the TM ranging from 0.5 to 1.0 mJ per pulse. The maximum energy level at which no bubble formation was observed determined choice. RESULTS: The average preoperative IOP was 22.4 mmHg. Six months after the operation, mean IOP reduction was 4.4 mmHg, and mean outflow pressure (OP) reduction was 38.1%. One month after the operation 68.7% of patients responded to treatment with an OP reduction of at least 20% ("responders"). Transient IOP elevation of 5 mmHg or greater was seen in 25.4% of patients. The success rate at 6 months after operation was 64.6% for all patients (67 eyes) and 78.2% for the responders (46 eyes). An analysis using a Cox proportional hazard model showed that a low preoperative IOP was the significant determinant for success, and the hazard ratio for the IOP increase of 5 mmHg was 2.12. Other factors such as age, gender, past history of ALT, and goniopigment were not significantly related to success. CONCLUSION: SLT appears to be a safe and effective way to lower IOP.

Adult↗
PubMed1995

Glaucoma triple procedure comprising trabeculotomy with a fornix-based scleral flap.

A new triple surgery procedure was applied to 20 primary open-angle glaucomatous (POAG) eyes. This technique comprises trabeculotomy with narrow (2-3 mm) fornix-based scleral flap, combined with extracapsular cataract extraction (ECCE) and posterior chamber intraocular lens (PC-IOL) implantation. As to surgical results, at two years postsurgery 53% (9/17) of the eyes were controlled under 21 mm Hg without medication, 35% (6/17) with topical medication alone. Eighteen (90%) eyes showed improved visual acuity of two or more Snellen lines. No serious postoperative complications occurred. There was no significant difference in postoperative astigmatism as compared with ordinary ECCE and PC-IOL surgery. Trabeculotomy with fornix-based scleral flap offers the advantage of simple and safe surgery when combined with ECCE and PC-IOL implantation.

Aged↗
PubMed1995

Ocular surface abnormalities in aniridia.

PURPOSE: The purpose of this study was to examine ocular surface abnormalities in aniridia. METHODS: We prospectively studied the ocular surface in nine consecutive patients (18 eyes) with virtually total aniridia. Of the 18 eyes, two eyes (two patients) were excluded from the study because severe surgical damage was likely to be the main cause of their corneal abnormalities. Six volunteers whose eye examinations yielded normal results served as control subjects. Detailed slit-lamp biomicroscopic examinations were performed to assess corneal findings and confirm the presence or absence of the palisades of Vogt. Goblet cell density on the peripheral corneal epithelium and inferior conjunctival epithelium was calculated via impression cytology and was statistically compared between aniridic eyes and control eyes. RESULTS: All 16 aniridic eyes had superficial corneal opacification and vascularization of either the peripheral or entire cornea. Palisades of Vogt were completely absent all around the limbal area. Goblet cell density on the peripheral cornea and inferior conjunctiva showed a statistically significant increase in the aniridic eyes (226 +/- 169 cells/mm2 and 406 +/- 203 cells/mm2), as compared with the control eyes (O cells/mm2 and 181 +/- 89 cells/mm2) (P = .0005 and P = .0102). CONCLUSIONS: These findings suggest that, in the aniridic eye, conjunctival epithelium invades the cornea because of corneal epithelial stem cell deficiency.

Adolescent↗
PubMed1994

Epithelial wound healing in the denervated cornea.

We studied the epithelial healing of denervated corneas in New Zealand albino rabbits with their left trigeminal ganglia surgically amputated. On the 14th day after amputation, the corneas were keratectomized (in 8.5 mm diameter) and documentation of the healing process began. We calculated the epithelial healing rate using simple regression analysis. We observed a mean healing rate of 0.463 +/- 0.059 mm2/hr (mean +/- SE) in the denervated corneas, compared to 0.609 +/- 0.031 mm2/hr in the control corneas; a statistically significant difference of P < 0.001. We performed scanning electron microscopic observation (SEM) at three points; before keratectomy, 48 hrs after keratectomy, and 14 days after keratectomy. SEM observation revealed that, in contrast to the control corneas, the surface of the epithelial cells in denervated corneas appeared rough with numerous exfoliating cells observed. This indicates that the epithelial cells might attach only weakly to the floor in denervated corneas. Transmission electron microscopic observation (TEM) performed at 48 hrs and 14 days after keratectomy also supports this finding. For example, the intercellular space is widened and fewer desmosomes are observed in denervated corneas. Using immunohistochemistry, the surface of the wound bed was covered with fibronectin in a similar fashion to the control. In the late stage, the denervated corneas demonstrated spontaneous epithelial breakdown with 83% of them having persistent epithelial defects. Epithelial healing in the control corneas displayed no abnormal signs. On the 14th day after keratectomy, these eyes were enucleated for immunohistochemistry using bromodeoxyuridine (Brd U) to observe dividing cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Selective suppression by bunazosin of alpha-adrenergic agonist evoked elevation of intraocular pressure in sympathectomized rabbit eyes.

PURPOSE: To determine whether there is alpha 1-adrenergic receptor heterogeneity associated with the regulation of intraocular pressure (IOP) and mydriasis in rabbits, the authors tested the hypothesis by characterizing the ability of the selective alpha 1-adrenergic antagonist, bunazosin, to block the ocular hypertensive and mydriatic responses to alpha 1-adrenoceptor stimulation by either norepinephrine (NE) or phenylephrine (PE). METHODS: The effects of topical application of bunazosin on IOP and pupillary diameter were measured in unilateral superior cervical ganglionectomized (SCGX) rabbits after exposure to either NE or PE. RESULTS: Bunazosin (0.1%) alone only lowered the IOP in the normal eye and did not elicit a pupillary response on either side. NE (0.01-1.0%) by itself caused a concentration-dependent rise in IOP on both sides, but mydriasis did not occur on the normal side. In SCGX eyes, the sensitivity of the IOP response to NE increased tenfold over that measured on the normal side. Unlike on the normal side, concentration-dependent mydriatic responses occurred with 0.1 and 1% NE. After pretreatment with bunazosin (0.1%), neither NE (0.1%) nor PE (0.1%) evoked a rise in IOP. However, the mydriatic response to either one of these agonists in the SCGX eyes was less affected. By contrast, pretreatment with the alpha 2-adrenergic antagonist, 0.5% yohimbine, did not change the IOP increase elicited by 0.1% NE. CONCLUSIONS: These results suggest that the alpha 1-adrenergic receptors that regulate IOP and pupillary diameter are different from one another in the rabbit.

Adrenergic alpha-Antagonists↗
PubMed1993

[Corneal epithelial wound healing in the denervated eye].

We investigated the rate of corneal epithelial wound healing in rabbits which had undergone surgical trigeminal denervation. Seven New Zealand albino rabbits underwent unilateral neurotomy of postganglionic trigeminal nerves via intracranial route. At 14 days after operation, 10 mm diameter central corneal epithelial defects were created in both eyes by n-heptanol. The area of epithelial defect was then photographed at 12-hour intervals and the epithelial healing rate was calculated (1st experiment). At 14 days after epithelial wound closure, the corneal epithelium was again denuded in a similar fashion (2nd experiment). The epithelial healing rate of the denervated and control eyes respectively were 1.28 +/- 0.25 and 1.39 +/- 0.31 (mm2/hr) in the first experiment, and 1.05 +/- 0.20 and 1.44 +/- 0.22 (mm2/hr) in the second. There was a statistically significant difference in the epithelial healing rate between the two groups in experiment 2 (p < 0.05), These results indicate that corneal epithelial wound healing is impaired in the denervated eye.

Animals↗
PubMed1992

[Effect of trigeminal denervation on rabbit corneal epithelium].

To investigate the effects of trigeminal denervation on the corneal epithelium, left postganglionic trigeminal neurotomy via intracranial approach was performed in 22 rabbits. Among 16 rabbits survived successfully, 13 denervated eyes (81%) showed corneal epithelial abnormalities that included 4 epithelial defects and 9 epithelial opacities. The remaining 3 eyes were normal. Histological examination showed many atrophic epithelial cells and the thinning of the corneal epithelial layer in the denervated eyes with corneal opacities. There was no abnormality in corneal stroma or endothelium. The ratio of epithelial to total corneal thickness calculated by a computer-assisted image analyzer was 6.5 +/- 2.1 (%) in control eyes and 3.8 +/- 1.9 (%) in the denervated eyes, the two values being significantly statistically different (p less than 0.001).

Animals↗
PubMed1991

Marked intraocular pressure response to instillation of corticosteroids in children.

We examined intraocular pressures of patients with strabismus whose eyes were instilled with corticosteroid eyedrops after a strabismus operation. Group A consisted of 11 children under 10 years of age whose eyes were instilled with 0.1% dexamethasone; Group B consisted of nine patients 10 years old or older whose eyes were instilled with 0.1% dexamethasone; and Group C consisted of 13 children under 10 years of age whose eyes were instilled with 0.1% fluorometholone. In Group A, four patients had intraocular pressures greater than 30 mm Hg, five had intraocular pressures from 21 to 30 mm Hg, and two had intraocular pressures under 21 mm Hg one or two weeks postoperatively. The intraocular pressure decreased to less than 21 mm Hg one week after discontinuation of dexamethasone treatment in all nine patients. No patients in Groups B or C had intraocular pressures greater than 20 mm Hg. Our results suggest that marked ocular hypertensive response to 0.1% dexamethasone treatment occurs frequently in children under 10 years of age.

Administration, Topical↗
PubMed1991

[The effect of bunazosin hydrochloride on intraocular pressure and aqueous humor dynamics in human].

The effects of bunazosin hydrochloride, a new highly selective alpha 1 adrenergic antagonist, on the intraocular pressure (IOP) and aqueous humor dynamics in healthy human volunteers were studied. Unilateral topical administration of 0.1% bunazosin significantly lowered IOP from 1 to 10 hrs in bunazosin-treated eyes, and from 2 to 8 hrs in contralateral placebo-treated eyes, with its maximum reduction at approximately 3 hrs, when the IOP decreased 5.0 mmHg in treated eyes, and 3.5 mmHg in contralateral eyes from the baseline, respectively. Fluorophotometrically measured aqueous humor flow rates did not change significantly either in treated or contralateral eyes. Bunazosin caused significant reduction of systolic and diastolic blood pressure 5 hr after application. The difference in pupil diameter between treated and contralateral eyes was found to be statistically significant from 1 to 5 hrs. A small but significant increase in anterior chamber depth also was observed from 2 to 6 hrs. Pulse rate and refraction were not substantially altered. There was moderate conjunctival vessel dilation, however, no serious complications were encountered. The results suggest that bunazosin hydrochloride appears to have great clinical potential for ocular hypotensive therapy.

Adrenergic alpha-Antagonists↗
PubMed1991

[Ocular hypotensive effects of topically applied bunazosin, an alpha 1-adrenoceptor blocker, in rabbits and cats].

Effects of topically applied bunazosin, an alpha 1-adrenoceptor blocker, on intraocular pressure (IOP) and pupillary diameter were investigated in normotensive rabbits and cats, in addition to experimentally hypertensive rabbits. Bunazosin (0.005% to 0.1%) applied to both eyes significantly lowered IOP in a concentration-dependent manner in normotensive rabbits and cats. The unilateral application of 0.1% bunazosin significantly lowered the IOP in the treated eye, whereas it caused no significant change in the contralateral eye, suggesting that the effect of bunazosin is due mainly to a direct and local action and is not systemic. Bunazosin was also effective in experimentally hypertensive models induced both by water-loading and by alpha-chymotrypsin in rabbits. There was a significant correlation between the IOP decrease caused by bunazosin and the IOP value before the application, indicating that the IOP-lowering action of bunazosin is dependent on the height of the original IOP level. Bunazosin had no influence on pupillary diameter even when 0.5% was applied to rabbits. Topically applied bunazosin may be useful as a new antiglaucoma agent.

Administration, Topical↗
PubMed1991

[Effect of intraocular pressure measurement through therapeutic soft contact lenses by noncontact tonometer].

The measurement of intraocular pressure (IOP) was compared with and without soft contact lenses by a non-contact tonometer. The soft contact lenses examined were Plano-T and Plano-B4 therapeutic contact lenses and Breath-O refractive lens. Twenty-nine eyes of 18 patients with an IOP ranging from 9 to 48mmHg were studied. The measurements of IOP were 19.7 +/- 8.6mmHg with Plano-T and 18.9 +/- 9.2mmHg with Plano-B4. Both numbers were not statistically different, when compared with controls (19.3 +/- 9.8mmHg without lens). There was, however, a significant difference significant difference with (44.7 +/- 10.7mmHg) and without the Breath-O (p less than 0.01). The results suggest that accurate IOP measurements can be obtained through therapeutic soft contact lens by a non-contact tonometer.

Adolescent↗
PubMed1988

Peptide immunoreactivity of the ciliary ganglion and its accessory cells in the rat.

By means of immunohistochemistry, calcitonin gene-related peptide, Leu-enkephalin and neuropeptide Y localize to rat ciliary and accessory ganglion cells. The proportion of ciliary and accessory neurons immunoreactive to each peptide is provided and compared to previous data for vasoactive intestinal peptide. These findings indicate considerable neurochemical complexity for a parasympathetic ganglion with a small cell population.

Animals↗
PubMed1988

Pterygopalatine ganglion cells contain neuropeptide Y.

By immunohistochemistry, neuropeptide Y (NPY) localizes to neurons in the rat pterygopalatine ganglion. These cells also are intensely or moderately reactive with acetylcholinesterase histochemistry. In contrast, both tyrosine hydroxylase immunohistochemistry and glyoxylic acid-induced fluorescence for catecholamines stain smaller clustered cells, similar in appearance to small intensely fluorescent (SIF) cells and clearly distinct from the NPY-immunoreactive cells. By reverse phase high-performance liquid chromatography, the NPY-immunoreactive material in the rat pterygopalatine ganglion migrates as a single peak characteristic of the peptide. We conclude that NPY-containing cholinergic cells are present in this classical parasympathetic ganglion. NPY-like immunoreactive neurons similarly occur in the pterygopalatine ganglion of the guinea pig.

Acetylcholinesterase↗
PubMed1987

A quantitative correlation of substance P-, calcitonin gene-related peptide- and cholecystokinin-like immunoreactivity with retrogradely labeled trigeminal ganglion cells innervating the eye.

To evaluate the intraganglionic organization of ocular sensory neurons in the guinea pig, we studied the retrograde axonal transport from the eye to the trigeminal ganglion of cholera toxin B subunit and then applied immunohistochemistry for substance P, calcitonin gene-related peptide and cholecystokinin. Retrogradely labeled cells were observed only in the anteromedial portion of the ipsilateral ganglion. We observed no somatotopical organization to trigeminal neurons containing any of these three peptides, either for cells projecting to the eye or for the ganglion as a whole. The relative proportion of neurons immunoreactive for each of these three peptides was similar among the population of neurons retrogradely labeled with cholera toxin B and among the population of neurons without direct projections to the eye.

Animals↗