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Body condition in mammals fluctuates depending on energy intake and expenditure. For brown bears (Ursus arctos), high‐protein foods facilitate efficient mass gain, while lipids and carbohydrates play important roles in adjusting dietary protein content to optimal levels to maximize energy intake. On the Shiretoko Peninsula, Hokkaido, Japan, brown bears have seasonal access to high‐lipid pine nuts and high‐protein salmon. To assess seasonal and annual fluctuation in the body condition of adult female brown bears in relation to diet and reproductive status, we conducted a longitudinal study in a special wildlife protection area on the Shiretoko Peninsula during 2012–2018. First, analyses of 2,079 bear scats revealed that pine nuts accounted for 39.8% of energy intake in August and salmon accounted for 46.1% in September and that their consumption by bears varied annually. Second, we calculated the ratio of torso height to torso length as an index of body condition from 1,226 photographs of 12 adult females. Results indicated that body condition continued to decline until late August and started to increase in September when salmon consumption increased. In addition, body condition began to recover earlier in years when consumption of both pine nuts and salmon was high. Furthermore, females with offspring had poorer body condition than solitary females, in particular in late August in years with low salmon consumption. Our findings suggest that coastal and subalpine foods, which are unique to the Shiretoko Peninsula, determine the summer body condition of female brown bears, as well as their survival and reproductive success., To clarify seasonal and annual fluctuation in the body condition of adult female brown bears in relation to food habits and reproductive status, we conducted a 7‐year longitudinal study that included scat sampling and direct observation of bears in a special wildlife protection area on the Shiretoko Peninsula. Using photographic evaluation to assess the body condition of free‐ranging brown bears, we noninvasively monitored the body condition of identifiable bears throughout the study period. Our findings suggest that coastal and subalpine foods, which are unique to the Shiretoko Peninsula, determine the summer body condition of female brown bears as well as their survival and reproductive success.

Knowing the reproductive characteristics of a species is essential for the appropriate conservation and management of wildlife. In this study, we investigated the demographic parameters, including age of primiparity, litter size, inter-birth interval, reproductive rate, and cub survival rate, of Hokkaido brown bears (Ursus arctos yesoensis) in the Rusha area on the Shiretoko Peninsula, Hokkaido, Japan, based on a long-term, individual-based monitoring survey. A total of 15 philopatric females were observed nearly every year from 2006 to 2016, and these observations were used to estimate reproductive parameters. The mean age of primiparity was 5.3 ± 0.2 (SE) years (n = 7, 95% CI = 5.0-5.6). We observed 81 cubs in 46 litters from 15 bears. Litter size ranged from one to three cubs, and averaged 1.76 ± 0.08 (SE) cubs/litter (95% CI = 1.61-1.91). Inter-birth intervals ranged from 1 to 4 years, and the mean value was estimated as 2.43 (95% CI = 2.16-2.76) and 2.53 (95% CI = 2.26-2.85) years in all litters and in litters that survived at least their first year, respectively. The reproductive rate was estimated from 0.70 to 0.76 young born/year/reproductive adult female, depending on the method of calculation. The cub survival rate between 0.5 and 1.5 years ranged from 60 to 73%. Most cub disappearances occurred in July and August, suggesting that cub mortality is mainly due to poor nutrition in the summer. All reproductive parameters observed in the Rusha area on the Shiretoko Peninsula fell within the range reported in Europe and North America, and were among the lowest or shortest age of primiparity, litter size, and inter-birth intervals, and ranked at a high level for reproductive rate.

The aim of this study was to determine the short-term effects of topical tafluprost, a novel prostaglandin F(2) derivative, on feline retinal circulation.Seventeen (17) adult cats were anesthetized with enflurane and mechanically ventilated. One (1) drop of tafluprost (0.0015%; n = 8), latanoprost (0.005%; n = 5), or control vehicle (n = 4) was instilled in 1 eye and the fellow eye was untreated. We measured the intraocular pressure (IOP), vessel diameter, and blood velocity simultaneously for 120 min in the large retinal arterioles and calculated the retinal blood flow (RBF) with a laser Doppler velocimetry system.Tafluprost 0.0015% significantly increased RBF (maximum change, 42.8 +/- 4.2% [mean +/- standard error of the mean; P0.01) and blood velocity (maximum change, 24.1 +/- 3.3%; P0.01) for 120 min after instillation; there was no significant change in vessel diameter. Latanoprost 0.005% significantly increased RBF (maximum change, 31.7 +/- 3.4%; P0.05); there was no significant change in vessel diameter and blood velocity. There were no significant differences in the IOP reduction among the three groups.We observed, for the first time, that topical tafluprost significantly increased RBF in cats, suggesting that dual-action tafluprost may be a beneficial antiglaucomatous agent for reducing IOP and increasing RBF.

Complexes between TiO 2 and sugar alcohol molecules or polyol molecules were prepared by heating the mixture of titanium isopropoxide (TIP) and ethylene glycol, glycerin, meso-erythritol, or D-mannitol aqueous solution at 368 K for 24 h. The degree of crystallization of TiO 2 in the obtained TiO 2 -sugar alcohol or polyol complex depended on the concentration of the polyol and sugar alcohol aqueous solution. When the TiO 2 -sugar alcohol or polyol complex was prepared by using the same concentration of the sugar alcohol or polyol aqueous solution, the degree of crystallization of the TiO 2 in the complex decreased with increase in the number of OH groups per molecule. According to the results of the DTA measurements and the element analysis, the strength of the interaction between Ti 4+ ions and polyol or sugar alcohol molecules increased with increases in the number of OH groups in the molecules. The heat treatment of TiO 2 -D-mannitol complex in 0.5 mol/l HNO 3 aqueous solution at more than 318 K enabled to obtain TiO 2 -D-mannitol complex nanoparticles by breaking the bonds between the D-mannitol molecules and Ti 4+ ions. The obtained TiO 2 -D-mannitol complex nanoparticles had large surface area which was more than 300 m 2 /g and showed photocatalytic activity. Furthermore, the complex nanoparticles can be dispersed into the distilled water with high stability.

To evaluate the effect of nucleotide P2Y(2) receptor agonists INS542 and uridine 5'-triphosphate (UTP) on the outward active transport of fluorescein across rabbit blood-retina barrier (BRB) in vivo.Injection (0.1 ml) of INS542 (0.1 or 1mM), phosphate buffered solution, or UTP (1 or 10mM) was made in Dutch-belted rabbits. Differential vitreous fluorophotometry (DVF) was performed 3hr later and the fluorescein (F)/fluorescein monoglucuronide (FG) ratio was then calculated. F/FG ratios are inversely proportional to outward active transport of F across BRB at the level of the retinal pigment epithelium (RPE). In another set of experiments, the effect of 0.1 ml vitreous injection of INS542 (1mM) on F/FG ratios was evaluated at different time points ranging from 0.5 to 48hr before conducting DVF.F/FG ratios obtained 3hr after intravitreal injection were as follows (mean+/-standard error): 0.49+/-0.14 (0.1mM INS542), 0.19+/-0.04 (1mM INS542), 0.48+/-0.09 (PBS), 0.40+/-0.08 (1mM UTP) and 0.36+/-0.05 (10mM UTP). The F/FG ratio for 1mM INS542 was significantly lower than in the other groups (P0.05). In the time course experiments, a significant decrease in the F/FG ratios was observed between 1 and 12hr following administration of INS542 when compared with F/FG ratios obtained in the contralateral (untreated) eye.Intravitreal administration of INS542 (but not UTP) enhances outward active transport of F across RPE in intact rabbit eye, indicating that activation of P2Y(2) receptors in vivo directly stimulates RPE active transport.

Ti-peroxy compound was synthesized from Ti(O-iPr)4 and H2O2. Anatase and rutile TiO2 nanoparticles were prepared by heating the Ti-peroxy compound diluted with a polyol aqueous solution at 368 K for 24 h. In this research, ethylene glycol, glycerin, erythritol, and D-mannitol were used as polyols in the diluting solution. The ratio of anatase/rutile of the TiO2 obtained depended on the polyol concentration in the diluting solution. Furthermore, the polyol concentration at which single-phase anatase could be obtained was lowest when the number of OH groups in the polyol molecule was the highest. With increasing polyol concentration, the obtained TiO2 nanoparticles showed increasing specific surface area and decreasing particle size.

Purpose To describe a newly developed stabilized retinal laser Doppler instrument, to report the reproducibility of retinal blood flow measurements, and to present examples of its clinical application. Design Experimental study. Methods The intrasession, intersession, and interobserver reproducibility of retinal blood flow measurements obtained using the Canon Laser Blood Flowmeter model CLBF 100 was assessed. Intrasession: the coefficients of variation (CV) for repeated measurements (5X) of retinal vessel diameter (D), time-average centerline blood velocity (V av ), and blood flow (F) were calculated at 18 sites along temporal retinal arteries and 18 sites along temporal retinal veins using both eyes in six healthy volunteers. Intersession: the correlation coefficients and average differences between two sets of measurements at the same 36 retinal sites made by one examiner on two different days were calculated. Interobserver: the correlation coefficients and average differences between two sets of measurements at nine sites (five arterial and four venous) in five eyes of five of the volunteers made by two examiners on the same day were calculated. Results from two patients, one with branch retinal vein occlusion (BRVO), and one with central retinal vein occlusion (CRVO), are used to illustrate abnormal retinal circulatory characteristics. Results Intrasession: CV (mean ± SD) for D, V av , and F were 5.5% ± 2.2%, 13.1% ± 6.3%, and 13.8% ± 4.7% in arteries and 3.5% ± 2.1%, 11.9% ± 5.9%, and 12.7% ± 5.5% in veins. Intersession/interobserver: strong correlations between measurements made by one examiner on two different days and by two examiners on the same day were found in D, V av , and F. Average differences in F were 16.4% ± 12.8% for intersession and 12.6% ± 7.0% for interobserver comparisons. Results from the patient with BRVO show marked differences in flow characteristics in the affected quadrant compared with an unaffected quadrant in the same eye, and to the fellow eye. Results from the patient with CRVO show a dramatic improvement in flow characteristics after clearing of the occlusion. Conclusions The reproducibility results and the fact that blood flow is measured in actual units of μl/min indicate that the instrument can be used for reliable comparison of blood flow characterictics at different retinal vascular sites in the same eye, at comparable sites in both eyes, and for comparison between patients and healthy control subjects.

Zinc oxide (ZnO) nanoparticles were obtained by firing the zinc peroxide nanoparticles at more than 473 K for 2 h. The zinc peroxide decomposed at 473 K to form ZnO that contained O22− ions. Furthermore, the ZnO nanoparticles without O22− ions were obtained by decomposition of the zinc peroxide at more than 513 K and the obtained ZnO contained oxygen vacancies. The increase of the unit cell parameter and the decrease of the activation energy for the electronic conduction were observed due to the oxygen vacancy. The ZnO nanoparticles also had lattice strain. The value of Δd/d decreased from 9.1 × 10−3 to 0 when the firing temperature was in the range from 473 K to 773 K.

Purpose: To investigate the effect of latanoprost (LP) on the inward and outward permeability (Pin and Pout) of the blood-retinal barrier (BRB). Methods: Four New Zealand white rabbits received topical LP (0.005%) once daily for 3 weeks in one eye and phosphate-buffered saline (PBS) in the fellow eye (topical group). Five New Zealand white rabbits were injected intravitreously with LP (0.1 ml, 0.005%) in one eye and PBS (0.1 ml) in the fellow eye (injection group). In the injection group, vitreous fluorophotometry (VFP) to estimate the Pin and differential vitreous fluorophotometry (DVF) to estimate the Pout were performed 60 min after LP was injected. After the baseline measurements, VFP and DVF were performed 60 and 180 min after intravenous injection of sodium fluorescein, respectively. Fluorescein (F) and fluorescein monoglucuronide (FG) concentrations were obtained by DVF, and the F/FG ratio was calculated as an index of the Pout. Results: In the topical group, there were no significant differences in the Pin or F/FG ratio between the LP- and the PBS-treated eyes. In the injection group, the Pin in the LP-treated eyes was significantly higher than in PBS-treated eyes (p < 0.05). There was no significant difference in the F/FG ratio between the two groups. Conclusion: Although we cannot exclude the effect of differences in species, the physiologic effect of LP, which increased the Pin, was seen in experimental studies. Because antiglaucoma drugs are generally used over an extended period, further clinical studies of the effect of LP on the BRB should be performed in patients who have BRB breakdown, such as in uveitis, and in patients who are pseudophakic and aphakic.

We used scanning laser ophthalmoscope (SLO) microperimetry to evaluate scotomas in patients with clinically significant diabetic macular edema (CSME) in type 2 diabetes mellitus.We studied 19 patients (mean age = 63 years; range, 45-78 years) (19 eyes). SLO microperimetry was performed in all eyes. We divided patients into three groups as follows: dense scotoma, relative scotoma, and no scotoma. The following variables were documented: age; duration of diabetes, hemoglobin A(1c) levels; logarithm of the minimum angle of resolution (Log(MAR)) visual acuity; refractive power; a history of panretinal photocoagulation; presence or absence of proliferative diabetic retinopathy, vitreomacular separation, and cystoid changes; the type of macular edema; and stability of fixation. All variables were compared in the three groups.We identified 4 eyes (21.1%) with dense scotoma, 10 (52.6%) with relative scotoma, and 5 (26.3%) with no scotoma. There were significant differences in log(MAR) visual acuity among those with dense scotoma (1.4 +/- 0.5), relative scotoma (0.6 +/- 0.2), and no scotoma (0.2 +/- 0.3) (P.05), and in the prevalence of cystoid changes, diffuse edema, and unstable fixation among those with dense scotoma (75%, 75%, and 100%, respectively), relative scotoma (20%, 30% and 50%, respectively) and no scotoma (0%, 0% and 0%, respectively) (P.05).Macular scotoma was observed by SLO microperimetry in 74% of the patients in this study. A scotoma in CSME is related to the formation of cystoid changes and the type of macular edema. In eyes with CSME in type 2 diabetes mellitus, a scotoma in the macula causes visual acuity impairment and unstable fixation.

Objective To investigate the relationship between preoperative photoreceptor displacement and postoperative scotoma after unilateral idiopathic macular hole surgery. Design Prospective nonrandomized comparative self-controlled trial. Participants Twenty patients who underwent successful surgery for unilateral idiopathic macular hole participated in the study. Methods Kinetic perimetry using red and green filter glasses, black binocular fixation targets, and red and green selective monocular stimuli was performed preoperatively. Scanning laser ophthalmoscope (SLO) microperimetry was performed preoperatively and postoperatively. Results Sixteen patients had photoreceptor displacement preoperatively. In preoperative SLO microperimetry, all eyes with a macular hole had a scotoma; postoperatively, 12 of 16 had no scotoma. All four eyes with no preoperative photoreceptor displacement were noted to have a postoperative scotoma. The prevalence of postoperative scotoma in patients with preoperative photoreceptor displacement (4 of 16; 25%) was significantly lower than that in patients without preoperative photoreceptor displacement (4 of 4; 100%) ( P = 0.03). Conclusions The presence or absence of photoreceptor displacement preoperatively should affect postsurgical visual function. Photoreceptor damage may occur in eyes without photoreceptor displacement preoperatively, resulting in scotoma postoperatively.

Purpose. To investigate the effect of bucillamine for prevention of increasing blood-retinal barrier (BRB) permeability in streptozotocin (STZ)-induced diabetic rats. Methods. The groups included control and STZ-induced diabetic rats treated with or without bucillamine. Six months after intervention, the concentrations of reduced and oxidative glutathione (GSH and GSSG) in the retina were measured biochemically. In addition, vitreous fluorescein, which leaks from the vessels after intravenous injection of fluorescein sodium, was measured to evaluate BRB permeability. To evaluate the scavenging ability against the reactive oxygen species (ROS) in vitro, the second-order rate constant for the reaction of bucillamine with ROS was estimated from the kinetics based on the rate constant for the reaction of ROS. Results. The BRB permeability was significantly higher (p = 0.01) in diabetic rats not treated with bucillamine, and bucillamine inhibited the BRB permeability. The GSH concentration and the GSH/GSSG ratio in the retinas decreased in diabetic rats not treated with bucillamine; bucillamine inhibited the decrease of the GSH concentrations. The ROS scavenging activity of bucillamine was similar with that of GSH. Conclusions. In diabetic retinas, oxidative stress might increase, which may be one of the causes of BRB breakdown. The antioxidant effects of bucillamine might take part in inhibition of increased permeability of the BRB in diabetes.

Purpose. We investigated the inhibitory effects of bucillamine on formation of laser-induced choroidal neovascularization (CNV) in a rat model. Methods. Bucillamine administration (approximately 150?mg/kg/day) was started 1 week before photocoagulation and continued to the end of the study. Control groups received drinking water. Two weeks after photocoagulation, choroidal neovascularization development was evaluated using simultaneous fluorescein and indocyanine green angiography, and the maximal thickness of the lesions was measured histologically. Results. The incidence of CNV formation was 99.5 ± 0.2% [mean ± standard deviation (SD)] in control rats and 64.3 ± 15.1% with bucillamine (P < 0.01). Histological study showed that the thickness of the CNV lesions was 23.4 ± 6.5 µm (mean ± SD) in the bucillamine-treated rats, which was significantly decreased compared to that in controls (60.8 ± 9.2 µm) (P < 0.01). Conclusions. Our results suggest that bucillamine may inhibit the development of laser-i...

To evaluate serum prorenin levels in preterm infants with or without retinopathy of prematurity (ROP).Noncomparative retrospective case control study.Serum prorenin levels in children with a gestational age younger than 36 weeks were measured with antibody-activating direct enzyme kinetic assay.The mean prorenin concentrations were higher in preterm infants with ROP than in infants without ROP at every time point: from 26 to 30 weeks, 2326 +/- 334 microg/ml (mean +/- SE [standard error]) (n = 3) and 1164 +/- 234 microg/ml (n = 3), respectively (P.05); from 31 to 35 weeks, 1760 +/- 496 microg/ml (n = 10) and 957.1 +/- 139 microg/ml (n = 25) (P.05); from 36 to 40 weeks, 958.2 +/- 194.2 microg/ml (n = 23) and 470.1 +/- 32.6 microg/ml (n = 67) (P.01); and from 41 to 45 weeks, 575.8 +/- 148.4 (n = 9) and 385.6 +/- 47.9 (n = 13), which is not significantly different.Prorenin levels in preterm infants can predict which infants will develop ROP.

To study the early ocular abnormalities in young diabetic patients, corneal and lens autofluorescence was measured by fluorophotometry in 30 eyes of 30 insulin-dependent diabetic patients without retinopathy. The lens [f(l)] and the corneal [f(c)] autofluorescence values in diabetic patients were significantly higher than in controls. In diabetic patients, f(l) was significantly correlated with the duration of diabetes, the f(c) was significantly correlated with the duration of diabetes and the indices of metabolic control, i.e. HbA1c and fructosamine. Our study demonstrated that young diabetic patients clearly had corneal and lens abnormalities before the appearance of overt diabetic retinopathy. The f(c) value might be a good indicator of metabolic control in diabetic patients.

We developed a tree shrew model of diabetes using streptozotocin (STZ), and studied early ocular changes of diabetes (after one week of diabetes) by fluorophotometry. STZ was injected intraperitoneally at doses of sixty to 400 mg/kg body weight. Animals injected with more than 300 mg/kg of STZ developed diabetes. Corneal autofluorescence was significantly increased one week after STZ injection. These changes may be related to impairment of the ocular homeostatic mechanisms due to the onset of diabetes. Using this model, we might be able to obtain diabetic ocular impairment data closer to human data than in previous models of diabetes, because tree shrews are primates.

The effects of topically applied timolol (a nonselective beta-blocker) and UF-021 (a prostaglandin-related compound) on pulsatile ocular blood flow (POBF) were investigated in 9 healthy volunteers. One drop of either UF-021 or timolol was instilled in one randomly selected eye and the fellow eye received physiologic saline. Before and 90 min after drop instillation, we measured intraocular pressure (IOP), POBF, heart rate (HR) and blood pressure (BP). After a washout interval of at least 1 week, the other drug was instilled in the previously treated eye. IOP, POBF, HR, and PB were measured following the same protocol. After timolol administration, IOP and POBF decreased significantly in the treated eye (26%, p = 0.01, and 13%, p = 0.02, respectively) and in the fellow eye (11%, p = 0.01, and 11%, p = 0.03, respectively). HR also decreased (10%, p = 0.03), but BP did not change significantly. After UF-021 administration, no significant changes were found in IOP, POBF, HR, or BP. Our results suggest that in normal subjects timolol decreases POBF in both the treated and the untreated eyes, whereas UF-021 has no action on either IOP or POBF.

We investigated corneal and lens autofluorescence in patients with proliferative diabetic retinopathy (PDR) to determine a correlation between the two parameters and blood glucose levels and HbA1c.Corneal and lens autofluorescence levels in 17 PDR patients and 8 healthy controls were measured with a fluorophotometer fitted with an anterior segment adapter. We measured the lower blood glucose level (BS1), corneal autofluorescence (CA1), and lens autofluorescence (LA1) simultaneously and the higher blood glucose level (BS2), CA2, and LA2 simultaneously on the same day. We defined parameter changes as: delta BS = BS2 - BS1, delta CA = CA2 - CA1, and delta LA = LA2 - LA1.Corneal and lens autofluorescence significantly increased in the patients, compared with the controls (p0.001). Lens autofluorescence had a significant positive correlation with HbA1c (r = 0.656, p0.01) in the patients. delta CA (ngEq/ml) correlated significantly with delta BS (mg/dl) (r = 0.631, P0.01).Results suggest that lens autofluorescence might represent the long-term control of diabetes, and corneal autofluorescence levels may represent short-term changes in the blood glucose level, because hyperglycemia accelerates with increasing corneal autofluorescence in PDR patients. Corneal and lens autofluorescence may be related to the breakdown of the blood-aqueous barrier.

To investigate the serum levels of prorenin and its correlation with the severity of diabetic retinopathy (DR).248 patients with diabetes and 108 control subjects were divided into four groups: no-DR (n = 146), no proliferative diabetic retinopathy (no-PDR) (n = 78), PDR (n = 24), and controls (n = 108). Serum levels of prorenin from all subjects were measured using the new antibody activating direct kinetic (AAD-PR) assay. The serum prorenin levels were compared among the groups.The serum levels of prorenin in the control, no-DR, no-PDR, and PDR groups, respectively, were 109.1 (66.1), 194.6 (160.4), 271.5 (220.3), and 428.4 (358.4) pg/ml (mean (SD)). Prorenin in the PDR group was remarkably high compared with the control and no-DR groups (p0.0001) and with the no-PDR group (p = 0.002). Serum levels of prorenin increased with increasingly severe retinopathy. No correlation was found between the prorenin level and the duration of disease or HbA(1c).The serum levels of prorenin in patients with PDR were found to be markedly high using the AAD-PR assay. Increased levels of prorenin in diabetes may have an important role in the pathogenesis of DR.

Recently, we have mobile adaptive information terminal to navigate like to present information during walking (ex. smartphone and glasses-type wearable terminal). On the other hand, attention to the surrounding environment is insufficient and incident is a familiar occurrence. It is considered to solve such a problem, it is important to behavior support by by measuring human behavior in real time and feedback information intuitive. Human walking is affected by vision, vestibular, somatic and other various sensations that come through the sensory-motor loop. But detail of the sensory-motor loop is not clear. In this study, we examined a possible affect of self motion sensation by an optical-flow stimulus in peripheral vision with a decayed soma to-sensory feeling by a vibration stimulus on leg and foot area. In the experiment, we presented the optical flow for forward direction to the peripheral vision, and then gave the self-motion sensation by changing the flow to left or right direction. In this paper, we discuss on the unifying mechanism of visual and somatic sensations based on the experimental result.

In 1981, Hoskin et al 1 described retinal pigment epithelial tears as a newly recognised severe complication of pigment epithelial detachment. Retinal pigment epithelial tears, which may occur either spontaneously or after laser photocoagulation to treat pigment epithelial detachment and choroidal neovascularisation (CNV) in diseases such as age related macular degeneration (AMD), usually cause sudden visual loss at the time of tearing. We report a case of spontaneous bilateral giant tears of the retinal pigment epithelium (RPE). A 79 year old woman was referred on 18 January 2002, because of sudden visual loss in the left eye of 2 weeks’ duration. In October 2001, the patient had undergone bilateral phacoemulsification and lens implantation by her local ophthalmologist. She had no apparent complications postoperatively, and the postoperative visual acuity (VA) was 20/250 in the right eye and 20/20 in the left eye; however, she noticed sudden decreased vision in the left eye on 3 January 2002, and visited the local ophthalmologist 5 days later. When she presented to our hospital, her VA was 20/200 in right eye and hand movements in the left eye. The intraocular pressure was 18 mm Hg in the right eye and 19 mm Hg in the left eye. The external eye examination, pupillary responses, and results …

Background: The effectiveness of losartan for the treatment of leucocyte entrapment in the retinal microcirculation of diabetic rats was evaluated quantitatively. Methods: After diabetes was induced by injection of streptozotocin (STZ), the rats were divided into two subgroups. The first subgroup (n = 6), received no medications; the second subgroup (n = 6) was given fresh drinking water supplemented with losartan (5 mg/kg/day) for 4 weeks. Six rats that were not injected with STZ or given medications served as controls. 4 weeks after intervention, leucocyte dynamics in the retina were observed using acridine orange digital fluorography. Leucocyte entrapment in the retina was compared among the three groups. Results: In the untreated diabetic rats, the number of trapped leucocytes (6.1 (SD 1.4) cells/mm2) increased significantly compared with control rats (2.8 (1.2) cells/mm2; p = 0.005) and diabetic rats treated with losartan (3.1 (0.9) cells/mm2; p = 0.0002). Conclusions: Losartan, an AT1 angiotensin II receptor antagonist, inhibited increased leucocyte entrapment in the diabetic retina. The authors demonstrated that losartan may have therapeutic efficacy in preventing development of diabetic retinopathy. Further clinical studies of the effect of the angiotensin receptor antagonist on preventing development of diabetic retinopathy are needed.

To investigate the inhibitory effects of losartan, an angiotensin receptor antagonist, on angiogenesis in a rat model of laser-induced choroidal neovascularization.Experimental study. Fifteen Brown-Norway male rats received losartan (approximately 5 mg/kg/d) in drinking water, and 15 Brown-Norway male rats received unsupplemented drinking water 1 week before photocoagulation, and it was continued to the end of the study. Two weeks after intense laser photocoagulation, choroidal neovascularization was evaluated by fluorescein angiography and histopathologic evaluation.The incidence of choroidal neovascularization formation was 99.5 +/-.2% (mean +/- standard deviation) in controls and 72.5 +/- 8.8% in losartan-treated rats (P.01). Quantitative morphometric assessment revealed mean choroidal neovascularization lesion thickness of 54 and 44.8 microm, respectively, in controls and losartan-treated rats (P.01).Losartan seems to inhibit development of laser-induced choroidal neovascularization. Angiotensin receptor antagonists may be useful as prophylaxis against choroidal neovascularization associated with age-related macular degeneration.

BACKGROUND Pulsatile ocular blood flow (POBF) is a parameter for evaluating choroidal blood flow. POBF in the patients with non-exudative and exudative age related macular degeneration (AMD) was investigated. METHODS POBF, pulse amplitude (PA), systolic and diastolic blood pressures, intraocular pressure (IOP), refractive error, and axial length were compared among 10 patients with non-exudative AMD, 11 patients with exudative AMD, and 69 age matched controls. A Langham OBF computerised tonometer was used with the participants in the sitting position to measure POBF and PA. RESULTS No significant differences were found in age, systolic and diastolic blood pressures, IOP, or refractive error between patients with exudative and non-exudative AMD and the control subjects. In the patients with exudative AMD the POBF (median, 372.7 μl/min) and PA (median, 1.2 mm Hg) were significantly lower than in the patients with non-exudative AMD (median, 607.0 μl/min (p = 0.02) and 2.2 mm Hg (p = 0.04), respectively) and control subjects (median, 547.4 μl/min (p = 0.01) and 2.0 mm Hg (p = 0.01), respectively). CONCLUSIONS These data show that the POBF and PA in the patients with exudative AMD are lower than in the patients with non-exudative AMD and normal subjects. Decreased choroidal blood flow may have a role in the development of choroidal neovascularisation in AMD.

To compare the affect upon bacterial flora found in the conjunctival sacs and the microbial sensitivity of a gatifloxacin (GFLX) ophthalmic solution prospectively with two instillation method groups.In one group (group A) GFLX solution was instilled postoperatively eight times/day for 2 days and subsequently four times/day for 12 days. In the other group (group B) the solution was instilled four times/day for 28 days. We investigated bacterial flora in the conjunctival sacs of patients who were to undergo cataract surgery, and tested for microbial sensitivity.There was no significant difference in the detection rate of bacterial flora in the conjunctival sacs. One bacterial isolate resistant to LVFX was identified in group A, and one resistant to GFLX and LVFX in group B.There is a possibility that the application of topical antibiotics may have little influence on positive culture. However, the occurrence of a resistance to GFLX indicates that the aimless use of antibiotics should be avoided during ophthalmic perioperative periods.

To study the effect of intravitreal bevacizumab on macular edema secondary to branch retinal vein occlusion (BRVO).6 eyes of 5 patients averaging 70 years, who had received either retinal photocoagulation or trans-tenon retrobulbar triamcinolone injections or both, but in whom the macular edema remained. There was an average of 337 days from BRVO onset to injection of bevacizumab. Corrected vision and foveal thickness were measured.Visual acuity and foveal thickness improved significantly one month after injection.Intravitreal injection of bevacizumab is effective for a short time.

Nitric oxide (NO) plays an important role in homeostatic vasodilation and the regulation of blood flow. On the other hand, excess release of NO causes various vascular complications. There are only a few reports on the relationship between plasma NO levels and microvascular complications, especially diabetic retinopathy (DR) in patients with type 2 diabetes. The purpose of this study was to determine the relationship between plasma NO levels and DR.In a prospective study, blood samples were obtained from 36 patients with diabetes and no diabetic retinopathy (NDR), 43 patients with nonproliferative diabetic retinopathy (NPDR), 18 patients with proliferative diabetic retinopathy (PDR), and 40 subjects without diabetes mellitus, who served as controls. The levels of plasma NOx (nitrite and nitrate), the stable metabolites of NO, were measured by high-performance liquid chromatography with the Griess method.The plasma NOx levels were 92.8 +/- 16.0, 70.2 +/- 6.8, 90.3 +/- 9.1, and 53.8 +/- 6.1 micromol/l in patients with NDR, NPDR, or PDR, and in the controls, respectively. The plasma NOx levels in the three diabetic groups were significantly higher than those in the control group (P0.05 in each case).The increased plasma NO levels in patients with type 2 diabetes indicate that NO may be associated with the pathogenesis of DR.

To investigate changes in choroidal blood flow (CBF) in the foveal region in patients with type 2 diabetes.Laser Doppler flowmetry was used to determine the CBF in the foveal region in 70 patients with type 2 diabetes and 36 age and sex matched healthy subjects (control group). The patients were classified into three groups: 33 patients (33 eyes) with no diabetic retinopathy (NDR), 20 patients (20 eyes) with non-proliferative diabetic retinopathy and no macular oedema (NPDR/MO-), and 17 patients (17 eyes) with NPDR and MO (NPDR/MO+). Optical coherence tomography was also used to measure the foveal thickness.The group averaged CBF values were 13.5 (4.9), 9.4 (2.5), 10.8 (4.8), and 5.6 (2.0) (arbitrary units) in the control, NDR, NPDR/MO-, and NPDR/MO+ groups, respectively. The group averaged CBF values in the NDR group decreased (30.2%; p0.01) compared with the control group. The average CBF value in the NPDR/MO+ group was also significantly lower (48.2%; p0.01) compared with that in the NPDR/MO- group.The CBF in the foveal region significantly decreases in patients with diabetes, especially those with macular oedema.

To evaluate quantitatively the effects of bucillamine on the entrapment of leukocytes in the retinal microcirculation of diabetic rats.13 male Brown Norway rats were injected with streptozotocin (STZ). After the animals developed diabetes, they were divided into two groups. Group 1 (n=7) received fresh drinking water without bucillamine, and group 2 (n=6) received fresh drinking water supplemented with bucillamine (200 mg/kg per day). Rats that were not injected with STZ and received water without bucillamine served as controls (n=6). Four weeks after the injection of STZ, the leukocytes in the retina were observed by acridine orange digital fluorography. The number of leukocytes trapped in the retinal vessels was compared among the three groups.In the untreated diabetic rats, the number of trapped leukocytes was significantly higher than in control rats or bucillamine-treated diabetic rats (P0.05).We demonstrated an inhibitory effect of bucillamine on leukocyte entrapment in the retinal vessels of diabetic rats. Bucillamine may have therapeutic efficacy in preventing the development of diabetic retinopathy.

To determine the changes in the pulse amplitude (PA) and the pulsatile ocular blood flow (POBF) after scleral buckling (SB).Retrospectively, we studied 24 patients (average age, 52 years) who had undergone SB to repair a retinal detachment in one eye. The patients were divided into two groups: those in whom SB had been performed less than 6 months earlier (n = 10), and those in whom the procedure had been performed more than 6 months previously (n = 14). In each group, the PA and the POBF were determined with a computerized tonometry system, and the values in the SB eyes were compared with those in the control fellow eyes.Within 6 months postoperatively, the mean PA in the SB eyes (0.66 +/- 0.30 mmHg) was significantly lower than that in the control eyes (1.43 +/- 0.34 mmHg; P0.05). The mean POBF in the SB eyes (349.5 +/- 154.1 microl/min) was also significantly lower than that in the control eyes (631.0 +/- 226.6 microl/min; P0.05). After more than 6 months postoperatively, there were no significant differences in the PA or the POBF between the SB eyes (1.08 +/- 0.49 mmHg and 612.4 +/- 341.2 microl/min, respectively) and the control eyes (1.50 +/- 0.51 mmHg and 589.5 +/- 278.4 microl/min, respectively).These results indicate that the choroidal blood flow decreases after SB but returns to normal levels after 6 months.

The determination of pulsatile ocular blood flow (POBF) by measuring intraocular pressure pulse is a reliable way of evaluating choroidal blood flow.We studied ocular haemodynamic abnormalities by examining the choroidal blood flow using POBF in patients with age-related macular degeneration (AMD).POBF was lower in patients with exudative AMD than in patients with non-exudative AMD and normal subjects.The decreased choroidal blood flow may induce choroidal neovascularization via angiogenic factor induced by hypoxia in patients with exudative AMD. Further studies of choroidal circulation, which may be important for the understanding the mechanism of AMD, are needed.

Keratoconus is an idiopathic, progressive, non-inflammatory ectasia of the axial cornea. Its association of other systemic disorders or ocular disease have been reported, but its specific origin remains unknown. Recently, Munier and associates detected that four types of autosomal dominant corneal dystrophy result from mutation in the human transforming growth factor β induced gene (βigH3), the product of which has shown to be the protein keratoepithelin (R555W for granular corneal dystrophy, R555Q mutation for Reis-Buckler’s corneal dystrophy, R124C mutation for lattice corneal dystrophy type I, and R124H mutation for Avellino corneal dystrophy).1 Molecular genetic analysis of various corneal dystrophies, which had previously presented an insuperable challenge to clinical diagnosis, now clearly demonstrates the distinct phenotypes.2 We report a rare case of bilateral keratoconus in association with Avellino corneal …

To investigate how nitric oxide (NO) contributes to the regulation of retinal circulation during rest and hypoxia in cats.N(G)-nitro-L-arginine-methyl ester (L-NAME; n = 7), an NO synthase inhibitor; N(G)-nitro-D-arginine methyl ester (D-NAME; n = 6), the inactive isomer; or phosphate-buffered saline (PBS; n = 7) was injected intravitreously. Hypoxia was induced in the cats by the administration of 10% oxygen. Vessel diameter and blood velocity were measured simultaneously in the anesthetized cats with a laser Doppler velocimetry system, and the retinal blood flow (RBF) and wall shear rate (WSR) were calculated as an index of shear stress on the retinal vessel wall.After intravitreous injection of L-NAME, the vessel diameter (-8.1% +/- 2.0%, P0.01), velocity (-17.0% +/- 3.7%, P0.01), and RBF (-29.4% +/- 4.6%, P0.01) significantly decreased compared with the preinjection level. In the PBS group, maximum increases above the prehypoxia diameter (13.7% +/- 3.5%, P0.01), velocity (39.5% +/- 8.6%, P0.01), RBF (73.9% +/- 10.6%, P0.01), and WSR (28.3% +/- 7.1%, P0.01) were observed during hypoxia. In the L-NAME group, those changes substantially decreased in response to hypoxia. D-NAME was inactive with regard to RBF during rest and hypoxia.These results suggest that NO may be continuously produced in the retina during rest and contributes to increased RBF during hypoxia. In addition, the increased WSR during hypoxia indicates that NO plays an important role in retinal hypoxic hyperemia through a flow-induced mechanism.

The purpose of this study was to investigate the response of the retinal arteriole to an acute increase in systemic blood pressure (BP).Sixteen healthy volunteers underwent a 5-minute cold pressor test (CPT) on the left hand. Retinal blood flow (RBF) was determined using a laser Doppler velocimetry system that enables simultaneous measurements of blood velocity and vessel diameter in a retinal artery every 30 seconds for the duration of the CPT. The mean arterial BP (MABP) was measured every 30 seconds during the test.The MABP immediately increased and reached the maximum level (from 85.1 +/- 2.7 to 103.7 +/- 5.0 mm Hg; P0.01) 1.5 +/- 0.2 minutes after the CPT began. The peak increase in velocity (from 30.6 +/- 1.3 to 46.1 +/- 2.1 mm/sec; P0.01) occurred at 1.6 +/- 0.2 minutes, resulting in an increase in RBF (from 10.1 +/- 1.0 to 14.3 +/- 1.4 microL/min; P0.01). The peak decrease in diameter (115.8 +/- 5.0 to 105.1 +/- 5.0 microm; P0.01) occurred at 2.9 +/- 0.3 minutes and the RBF returned to the baseline value. The increases in MABP significantly correlated with the decreases in diameter (r = -0.674, P = 0.0059).The CPT caused an acute increase in MABP that was associated with a transient increase in RBF and blood velocity, followed by constriction of the retinal arterioles and return of RBF to baseline. The results suggest that constriction of the retinal arterioles plays an important role in the maintenance of RBF in response to an acute increase in systemic BP.

To measure fluorescein (F) and fluorescein monoglucuronide (FG) concentrations in the vitreous and evaluate the effect of acetazolamide (AZM) on the outward permeability of the blood-retina barrier (BRB) using differential vitreous fluorophotometry (DVF).DVF was performed 180 minutes after intravenous injection of AZM (5 mg/kg) and 50 mg of sodium fluorescein in six rabbits (AZM group). DVF also was performed in six rabbits injected intravenously with only 50 mg of sodium fluorescein (control group). The F/FG ratio was calculated based on the concentrations of F and FG obtained by DVF. DVF also was performed 180 minutes after 50 mg of intravenous injection of sodium fluorescein in five rabbits given probenecid (150 mg/kg) intraperitoneally (probenecid group).The average F/FG ratio was 0.36 +/- 0.17 (range, 0.22-0.66) in the AZM group, which was significantly smaller than the control value of 0.74 +/- 0.22 (range, 0.50-1.60). The average F/FG ratio at 180 minutes after injection was 1.51 +/- 0.46 (range, 0.94-2.00) in the probenecid group, which was significant higher (p0.05) than that of the AZM or control group.This study showed that the F/FG ratio might be a good indicator of the estimated outward permeability of the BRB using DVF and that AZM may accelerate the outward active transport function of the BRB.

Background: To report an Asian patient with branch retinal vein occlusion secondary to neurofibromatosis 1. Case: A 64-year-old woman presented with a loss of vision in her right eye of 9-month duration. A diagnosis of neurofibromatosis 1 was made. A general medical examination showed no abnormalities except the signs of neurofibromatosis 1. Observations: Fundus examination of the right eye revealed irregularities of the venous caliber, partial sheathing of the corresponding vein and macular edema. Multiple dilated and tortuous collateral channels and an arteriovenous communication bridged the perfused and nonperfused retina. Fundus examination of the left eye showed a tortuous vein in the temporal region of the fovea. Fluorescein angiography of the right eye confirmed delayed filling in a superotemporal artery and in the corresponding vein. The temporal region of the fovea had large areas of capillary loss. The collaterals were tortuous and mimicked a neovascularization. Fluorescein angiography of the left eye confirmed that the vein in the temporal part of the fovea was tortuous and not leaking. A diagnosis of branch retinal vein occlusion of the superotemporal vein was made. Conclusions: Neurofibromatosis 1 should be considered in the differential diagnosis of retinal vascular occlusive disease without other risk factors.