Effect of cold atmospheric plasma/NO gas application with different exposure times on healing in wounds with tissue loss in diabetic rats.

Applications of cold atmospheric plasma/nitric oxide (CAP/NO) gas have recently garnered popularity when treating impaired wound healing in patients with diabetes. In this study, we aimed to investigate the effects of NO gas application for 60 and 120 s on wound healing in diabetic rats. A dorsal excision 3 cm in diameter was performed in 15 diabetic rats; these rats were categorized into the following 3 groups: DC (untreated diabetic control); DNO/60 (exposure to 200 ppm NO gas for 60 s/day); and DNO/120 (exposure to 200 ppm NO gas for 120 s/day). Wound contraction on days 0, 3, 7, 11, and 14 and wound contraction rate between days 0 and 14 were evaluated. On day 14, tissue samples were collected for histopathologic assessment of inflammation, epithelial regeneration, angiogenesis congestion, and collagen fiber organization. Normality of distribution was assessed using the Shapiro-Wilk test, and intergroup comparisons were performed using the Mann-Whitney U test (NPar Test) and the Kruskal-Wallis test (non-parametric ANOVA). Wound contraction during treatment days 7-14 was significantly greater in the NO-treatment groups than in the DC group (p<0.05). The NO60 s and NO120 s groups showed a significantly higher wound contraction rate than the DC group (p=0.033, p=0.049, respectively). Significant differences were noted between the control and NO groups in terms of inflammation (p<0.05) and between the control group and DNO/60 and DNO/120 groups in terms of collagen organization (p<0.05, p<0.01, respectively). Evaluation of epithelialization revealed significant intergroup differences between the control and NO treatment groups (p<0.01). In this study, the application of NO once a day for 60 seconds and 120 seconds in diabetic wounds contributed equally to wound healing.

Protective effect of Coriandrum sativum extract against inflammation and apoptosis in liver ischaemia/reperfusion injury.

BACKGROUND: The aim of this study was to investigate the anti-inflammatory and antioxidant effects of Coriandrum sativum extract on liver ischaemia reperfusion injury at light microscopic and biochemical levels. MATERIALS AND METHODS: Sham, ischaemia/reperfusion injury (IRI), IRI + Coriandrum sativum extract and only Coriandrum sativum extract groups were formed. Sixty minutes of ischaemia and 60 minutes of reperfusion were performed. In the treatment group, 300 mg/kg/day Coriandrum sativum was given by gavage. Hepatic tissues were fixed in 4% paraformaldehyde. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) enzymes were measured. Nuclear factor-kappa beta (NF-κB), tumour necrosis factor-alpha (TNF-α) and caspase-3 immunohistochemistry staining was performed. Microscopic scoring was performed in terms of sinusoidal congestion, vacuolisation, and necrosis. RESULTS: Sinusoidal enlargement and diffuse congestion, Kupffer cell increase, neutrophil increase in necrotic areas, vacuolisation in hepatocytes, and bile duct proliferation in the portal triad were observed in ischaemia/reperfusion hepatic tissue. Very rare, necrotic areas were observed in the Coriandrum sativum treatment group, while congestion and vacuolisation and bile duct proliferation were decreased compared to the ischaemic group. The AST and ALT levels were increased in the IRI and IRI + Coriandrum sativum groups. When compared to the IRI group, the AST and ALT levels of the Coriandrum sativum were considerably decreased. The IRI and IRI + Coriandrum sativum groups had statistically significant differences in ALP compared to that of the Coriandrum sativum and Sham groups. There was no significant difference between the ALP levels of the IRI and IRI + Coriandrum sativum groups TNF-α, NF-κB and caspase-3 immune positive stained hepatocytes were numerous and widely observed in the injury group. There were positive TNF-α immunohistochemical staining Kupffer cells in the IRI group. In the group treated with Coriandrum sativum, Kupffer cells were not stained, while TNF-α, NF κB and caspase-3 expressing hepatocytes were found to be decreased compared to the IRI group. When the expression values of the TNF-α, NF-κB and caspase-3 groups were evaluated statistically, it was seen that there was a significant decrease in the group treated with Coriandrum sativum. CONCLUSIONS: It was found that Coriandrum sativum extract decreased proinflammatory cytokine TNF-α and apoptotic cell death and liver enzymes in liver ischaemia/reperfusion injury.

Anterior chamber fixation of a posterior chamber intraocular lens: a novel technique.

We aimed to evaluate the implantation of a posterior chamber intraocular lens (IOL) in the anterior chamber (AC) with the haptics passing through two iridectomies to the posterior chamber. A total of 33 eyes of 33 patients with inadequate posterior capsular support due to either previous aphakia or posterior capsular rupture during cataract extraction were included in the study. A double iridectomy was performed on all patients using a vitrectomy probe on the midperiphery of the iris. IOLs were implanted in the AC, and the haptics were passed through the iridectomies to the posterior chamber. The mean follow-up time was 25.3 months. AC hemorrhage occurred in five patients during the iridectomy procedure. Corneal edema was detected in eight of 14 patients with primary IOL insertions. Haptic dislocation was detected in only one patient. This technique may be a good alternative to scleral-fixated IOL implantation in eyes with aphakia.

Characteristics of pellet injuries to the orbit.

PURPOSE: To investigate the features of orbital injuries by pellets fired from the front. DESIGN: Retrospective, 4 cases of pellet injuries. METHODS: Five orbits of 4 patients who sustained pellet injuries received from the front were reviewed retrospectively. The course of injury and results were assessed. Radiological examinations were reviewed. The patients were evaluated between December 1996 and June 2004. RESULTS: Five orbits of 4 patients sustained injuries caused by pellets fired from an anterior direction. The globe in the injured orbit was intact in 2 cases. Severe loss of vision was also present in these 2 globes due to optic nerve involvement. Final visual acuity was down to no light perception in 4 eyes and limited to light perception in 1 eye. CONCLUSIONS: The prognosis of orbital pellet injuries is, unfortunately, poor. A pellet passing through the floor of the orbit often causes double perforation of the globe and, once in the orbital aperture, it travels towards the apex as a result of the conical shape of the orbit and lodges in the optic canal or its entrance, severely damaging the optic nerve. Surgery or other treatments are usually unsuccessful. Even if the globe is intact, vision is usually severely impaired.

Protective role of alpha-tocopherol on retinal injury in experimental uveitis in guinea pigs.

PURPOSE: PURPOSEof the study was to determine whether alpha-tocopherol (AT) can protect the retina from oxidative damage in experimental uveitis (EU). MATERIAL AND METHODS: The eyes of 36 adult male guinea pigs were studied. The guinea pigs were divided into three groups of 12 animals each. The first group was used as control. The right eyes of groups 2 and 3 received an intravitreal injection of bovine serum albumin for EU induction. At the same time and also on the consecutive third and fifth days, group 3 received intraperitoneal AT injections. The samples were collected on the eighth day. Retinal malondialdehyde (MDA) levels and the average thickness of the inner plexiform layer were measured and the histopathology of the eyes was studied. RESULTS: The MDA level was significantly lower in the control group than in the groups 2 (p<0.01) and 3 (p<0.05). When compared with the EU group 2, there was a significant lowering of MDA in the AT injected group 3 (p<0.01). The thickness of the inner plexiform layer in the control group 1 was significantly lower than in the other groups (p<0.01). Its thickness in the group 3 supplied with AT was significantly lower than in the group 2 (p<0.01). CONCLUSIONS: The data indicate that intraperitoneal AT administration protects against EU injury in the guinea pig retina as evidenced by the reduced MDA and the thickness of retina.

Effects of intraperitoneal vitamin E, melatonin and aprotinin on leptin expression in the guinea pig eye during experimental uveitis.

PURPOSE: To observe ultrastructural changes and leptin expression in the guinea pig eye during experimental uveitis (EU) and the effects of vitamin E, melatonin and aprotinin on leptin expression. METHODS: Thirty male guinea pigs were randomly classified into five groups. Group 1 was the control group. Groups 2, 3, 4 and 5 received intravitreal injections of bovine serum albumin (BSA) to induce EU. At the same time on the third day, groups 3 (EU + vitamin E), 4 (EU + melatonin) and 5 (EU + aprotinin) received intraperitoneal vitamin E (150 mg/kg), melatonin (10 mg/kg) and aprotinin (20,000 IU/kg), respectively. On the sixth day, histopathological and clinical scoring of inflammation were performed, and leptin expression was investigated in the retina, choroid, sclera, episclera and cornea, and compared. RESULTS: There was a remarkable increase in leptin expression in the retina, choroid, sclera and episclera in the EU group. Leptin expression in the treatment groups was similar to that in the control group. At light and electron microscopic levels, ganglion cells were oedematous and inner plexiform layer thickness had increased in the EU group retinas. Oedema was decreased in the treatment groups. Comparison of the EU and treatment groups revealed significant differences histopathologically and clinically. CONCLUSION: Experimental uveitis causes an increase in leptin expression in the retina, choroid, sclera and episclera of guinea pigs. Vitamin E, melatonin and aprotinin inhibit this increase. Leptin seems to be closely related to ocular inflammation.

Leptin in corneas from keratoconus and infectious keratitis patients.

PURPOSE: Leptin is produced primarily by adipose tissue. More recent studies have shown extra sites of leptin production in physiologic and ill human tissues. However, whether leptin originates from human corneas in infectious keratitis and keratoconus is not known. The aim of this study was to demonstrate and quantitate leptin expression in corneas with infectious keratitis and keratoconus and make comparisons to control corneas. METHODS: We examined the immunohistochemical staining of leptin in nine corneas surgically excised from patients with infectious keratitis (3 patients), keratoconus (3 patients), and donor corneas (3 patients). RESULTS: The results were analyzed using a semiquantitative scoring system of mild, moderate, and strong. Cells of the infectious keratitis group had the strongest leptin staining intensity, the control group had moderate, and the keratoconus group had mild staining intensity. The more vascular corneas in the infectious keratitis group were also associated with the greatest leptin staining. CONCLUSIONS: Our findings indicate that leptin expression was present in all three sources of corneas (infectious keratitis, keratoconus, and normal control). Quantitative scoring would imply it may play a role in infectious keratitis, although further experiments are necessary to establish any causal relationship.

Moderate exercise combined with dietary vitamins C and E counteracts oxidative stress in the kidney and lens of streptozotocin-induced diabetic-rat.

Oxidative stress has a key role in the pathogenesis of diabetes-induced cataract formation and nephropathy. Daily moderate exercise and vitamins C and E (VCE) supplementation can be beneficial to diabetes due to reducing blood glucose and free radical production. The aim of this study was to analyze the effect of moderate exercise with vitamin VCE on lipid peroxidation (LP) and antioxidative systems in the kidneys and lens of streptozotocin-induced diabetic rats. Forty female Wistar rats were used. They were randomly divided into four groups. The first and second groups were used as control and diabetic groups. The third group was the diabetic-exercise group. VCE-supplemented feed was given to diabetic-exercise rats constituting the fourth group. Animals in the exercised groups were moderately exercised daily on a treadmill for three weeks (five days a week). Diabetes was induced on day zero of exercise. Body weights in the four groups were recorded weekly. Lens and kidney samples were taken from all animals on day 20. Glutathione peroxidase (GSH-Px), reduced glutathione (GSH), vitamin E, and beta-carotene levels in kidney and lens, albumin in plasma, and body weight were significantly lower in the diabetic group than in the control group, whereas there was a significant increase in LP of kidney and lens as well as plasma glucose, urea, and creatinine levels in the diabetic group. The decrease in antioxidant enzymes, vitamins, and albumin and the increase in LP and glucose levels in diabetic rats were significantly improved with exercise and VCE supplementation. In the diabetic animals, the decreased beta-carotene and vitamins A levels in kidney did not improve through exercise only, although their levels were increased by exercise plus VCE supplementation. In conclusion, these data demonstrate that lipid peroxidation increases in the lens and kidney of diabetic animals and this could be due to decreases in antioxidant vitamins and enzymes. However, dietary VCE with moderate exercise may strengthen the antioxidant defense system through the reduction of ROS and blood glucose levels. The VCE supplementations with exercise may play a role in preventing the development of diabetic nephropathy and cataract formation in diabetic animals.

Antioxidant effects of alpha-, gamma- and succinate-tocopherols in guinea pig retina during ischemia-reperfusion injury.

The purpose of this study is to investigate the efficacy of alpha-tocopherol (AT), gamma-tocopherol (GT) and d-alpha-tocopherol polyethylene glycol 1000 succinate (TPGS) in preventing the retinal injury followed by ischemia-reperfusion (IR). The eyes of 40 adult male guinea pigs were used in the study. The guinea pigs were divided into five groups of eight rats each. First and second groups were used as control and IR groups, respectively. Third, fourth and fifth groups received subcutaneously AT, GT and TPGS, respectively. Treatment with each vitamin was performed before 5min of ischemia with reperfusion at 6h intervals for three times. Retinal ischemia was induced for 90min, then followed by reperfusion for 24h. The animals were killed at 24h of reperfusion. Lipid peroxidation (LP) and glutathione (GSH) levels were measured in right retinas by using a spectrofluorometer. Retinal GSH levels were found significantly lower (p < 0.002) in the IR group than in control group and there was a significant increase in the LP levels in IR group (p < 0.001). The decrease of GSH and increase of LP levels in the IR animals were significantly (p < 0.05 and 0.001) improved by the administration of the Vitamin E forms. When compared to GT group, there were no significant differences in LP levels in AT and TPGS groups. However, LP level in AT group was significantly (p < 0.01) lower than in the TPGS group. The GSH levels were higher (p < 0.001) in AT and TPGS groups than in IR group. Therefore, modulator effect of AT and GT were greater than that of TPGS. In conclusion, present data demonstrate that there is an increase in the LP in the retina of IR-induced animals and a decrease in the GSH levels. However, subcutaneous AT, GT and TPGS were effective in preventing retinal injury followed by ischemia-reperfusion. The subcutaneous AT may play a role in treating IR injury.

Administration of high dose intravitreal melatonin degenerates retinal cells in guinea pigs.

The purpose of this study was to investigate the influence of intravitreally injected different doses of melatonin on retinal morphology. The right eyes of 35 male albino guinea pigs were used. The animals were classified randomly into five groups in equal numbers. First group was used as control and received intravitreal injection of placebo. Groups 2, 3, 4 and 5 received intravitreally injections of melatonin at 50, 100, 150 and 200microg/body weight (BW) each, respectively. The animals were sacrificed 15 days after the injections. The eyes were enucleated and processed for light microscopic evaluation. Intravitreal injection of melatonin at doses ranging from 50 to 150microg did not induce morphological changes, although a higher thickness of the inner plexiform layer (IPL) was found in Group 5 compared to other groups (p < 0.05). The mean retinal ganglion cell (RGC) counts were found to be lower in Group 5 compared to other groups (p < 0.05). Our findings indicate that intravitreal injection of melatonin at doses ranging from 50 to 150microg/BW does not induce morphological changes. The dose of 200microg/BW produced significant damage including retinal ganglion cell loss and formation of retinal edema.

Protective effects of intraperitoneal vitamin C, aprotinin and melatonin administration on retinal edema during experimental uveitis in the guinea pig.

A considerable amount of clinical and experimental evidence exists suggesting the involvement of reactive oxygen substances (ROS) in the aetiology of uveitis. The activated phagocytic system of polymorphonuclear leucocytes in uveitis is involved in the generation of ROS. In addition to their direct free radical scavenging action, aprotinin, melatonin and vitamin C are known to protect against oedema formation and can preserve plasma membrane fluidity and free radical production. Histological changes in the retina that occur during uveitis are not well explained. The purpose of this study was to determine whether vitamin C, aprotinin and melatonin can protect the retina from damage accompanying experimental uveitis (EU). Thirty adult male guinea pigs were divided into five groups of six animals each. The first group was used as control. The right eyes of groups 2, 3, 4 and 5 received an intravitreal injection of bovine serum albumin for induction of experimental uveitis. At the same time and also on the consecutive third day, groups 3, 4 and 5 received intraperitoneal injections of vitamin C (ascorbic acid, 100 mg kg(-1) body wt), aprotinin (20,000 kIU kg(-1) body wt) and melatonin (10 mg kg(-1) body wt), respectively. The animals were killed on the sixth day. The average thickness of the retina and inner plexiform layer for each eye was measured in sagittal section near the optic nerve and expressed in microns. The thickness of the retina and inner plexiform layer in the control group was significantly (p < 0.01) lower than in the group EU as compared with the group EU plus vitamin C, group EU plus aprotinin, group EU plus melatonin (p < 0.05). The thicknesses of the retina and inner plexiform layer in group EU plus vitamin C, group EU plus aprotinin and group EU plus melatonin were significantly (p < 0.01) lower than that in the group EU. The difference in thickness of the retina and inner plexiform layer among the groups 3, 4 and 5 was not significant (p > 0.05). In conclusion, this study demonstrated that oedematous effects of EU on the retina were reduced by the administration of intraperitoneal vitamin C, aprotinin and melatonin, i.e. these antioxidants had significant protective effects on the retina of guinea pigs against oedematous damage in EU. However, the reductive effect of vitamin C on EU was greater than that of aprotinin and melatonin. The intraperitoneal vitamin C, aprotinin and melatonin supplementations may strengthen the antioxidant defence system because of decreased ROS, and these agents may play a role in treating uveitis.

Protective effects of vitamin E forms (alpha-tocopherol, gamma-tocopherol and d-alpha-tocopherol polyethylene glycol 1000 succinate) on retinal edema during ischemia-reperfusion injury in the guinea pig retina.

PURPOSE: The purpose of this study is to provide evidence that free radical damage is a component of retinal ischemia-reperfusion (I/R) injury, and to determine whether alpha-tocopherol, gamma-tocopherol and d-alpha-tocopherol polyethylene glycol 1000 succinate (TPGS) can protect the retina from this injury. METHODS: The right eyes of 40 male guinea pigs weighing 500-600 g were used. The animals were randomly assigned to group 1 (control), group 2 (I/R), group 3 (I/R plus alpha-tocopherol), group 4 (I/R plus gamma-tocopherol) and group 5 (I/R plus TPGS). Groups 3, 4 and 5 received four subcutaneous injections at six-hour intervals for total dosage of 800 IU/kg alpha-tocopherol, 1000 IU/kg gamma-tocopherol and 750 IU/kg TPGS, respectively. The first dose of each substance was administered 5 minutes before retinal ischemia. Retinal ischemia was induced for 90 minutes, then followed by reperfusion for 24 hours. Injections of three substances were repeated at 6, 12 and 18 hours during reperfusion. The animals were killed at 24 hours of reperfusion. Sagittal sections of 4 microm were cut and stained with hematoxylin and eosin for light microscopic evaluation. The average thickness (edema) of the inner plexiform layer for each eye was measured in sagittal sections near the optic nerve and expressed in microns. RESULTS: All the three substances showed statistically significant protection against the formation of retinal edema during ischemia-reperfusion injury. The mean thickness of the inner plexiform layer were 15.0, 25.44, 19.81, 21.38 and 20.88 microm in control, I/R, I/R plus alpha-tocopherol, I/R plus gamma-tocopherol and I/R plus TPGS groups, respectively. The results showed that the thickness of the inner plexiform layer in group 1 (control) was significantly lower than the other groups (p<0.001). The inner plexiform layer was thicker in the I/R group than with I/R plus alpha-tocopherol (p<0.001), I/R plus gamma-tocopherol (p<0.001) and I/R plus TPGS (p<0.01). The inner plexiform layer was not thicker in the I/R plus TPGS group than in the I/R plus alpha-tocopherol and I/R plus gamma-tocopherol groups. Compared to the I/R plus alpha-tocopherol group, the inner plexiform layer was significantly thicker in the I/R plus gamma-tocopherol group (p<0.01). CONCLUSIONS: The results from these experiments indicate that vitamin E forms have protective effects on the retina during retinal ischemia-reperfusion injury, but, the effects of alpha-tocopherol and TPGS appear to be much greater than that of gamma-tocopherol.

Pigmented paravenous retinochoroidal atrophy. A literature review supported by seven cases.

Seven patients (4 men and 3 women, ranging in age from 27 to 64 years) with pigmented paravenous retinochoroidal atrophy, a rare disorder of unknown origin, were studied. The mean follow-up time was 18.5 months. Fundus examinations were performed, and color fundus photographs were taken. In addition to fluorescein angiography, visual field examinations, color vision and electroretinographic tests were performed. All 7 patients were asymptomatic, with visual acuities ranging from 3/10 to 10/10. Both fundi showed patches of retinochoroidal atrophy and pigmentation along the retinal veins in all patients. Fluorescein angiography showed hyperfluorescence due to the pigment epithelial atrophy together with hypofluorescence corresponding to bone spicule pigment clumping. Visual field tests showed scotomas corresponding with areas of atrophy along the retinal veins. The electroretinography showed reduced responses in 2 cases. Color vision was normal in all cases. The patients had no history of trauma or a previous inflammatory process. Serology for syphilis, Toxoplasma and cytomegalovirus as well as a skin test for tuberculosis were negative. When the patients were seen at the end of the follow-up period, no variation of the findings was noted. Although the fundus abnormalities can be mild or severe, retinal function tests indicated that this is a geographic and not a generalized disorder.

Aprotinin reduces ischemia-reperfusion injury in the retina of guinea pigs.

PURPOSE: The aim of this study was investigate the role of aprotinin on retinal lipid peroxidation and histopathological changes during ischemia/reperfusion (I/R) of guinea pigs. METHODS: Three groups of seven pigmented guinea pigs each were formed: a control (group 1), ischemia/saline (group 2) and ischemia/aprotinin (group 3). One eye of each animal was selected for histopathological evaluation and the other for biochemical assay. Bilateral pressure-induced retinal ischemia was instigated for 90 min and was followed by 24 hours of reperfusion. Animals in the ischemia/aprotinin and ischemia/saline groups received either 20,000 KIU/kg of aprotinin or saline, repeated four times at 6-hour intervals, with the first dose administered 5 min prior to the ischemic insult. The animals were killed at 24 hours of reperfusion. Retinal malondialdehyde (MDA) levels and the thickness of the inner plexiform layers were measured. RESULTS: The level of MDA in group 1 was significantly (p<0.001) lower than the other groups. The mean MDA level in group 2 was significantly (p<0.01) higher than in group 3. The inner plexiform layer in group 1 was significantly (p<0.001) thinner than in the other groups. The mean thickness of the inner plexiform layer in group 2 was significantly (p<0.01) higher than in group 3. CONCLUSIONS: These data indicate that intraperitoneally administrated aprotinin has a protective effect against I/R injury in the retina of guinea pig as evidenced by reduced retinal MDA level and retinal thickness.

Effects of melatonin, vitamin E and octreotide on lipid peroxidation during ischemia-reperfusion in the guinea pig retina.

PURPOSE: The purpose of this study is to provide evidence that free radical damage is a component of retinal ischemia-reperfusion (I/R) injury, and to determine whether melatonin, vitamin E and octreotide can protect the retina from this injury. METHODS: The right eyes of 50 male guinea pigs weighing 500-600 g were used. The animals were randomly assigned to group 1 (control), group 2 (I/R), group 3 (melatonin + I/R), group 4 (vitamin E + I/R) and group 5 (octreotide + I/R). Groups 3, 4 and 5 received four subcutaneous injections with a 6-h interval for a total daily dose of 10 mg/kg melatonin, 150 mg/kg vitamin E and 22 microg/kg octreotide. The first dose of each substance was administered 5 minutes before retinal ischemia, which was induced for 1.5 hours, followed by reperfusion for 24 hours. All three substances were repeated for 6, 12 and 18 hours during reperfusion. The animals were killed at 24 hours of reperfusion. Retinas were isolated and processed for the quantification of malondialdehyde (MDA). RESULTS: The compounds had the following relationships: melatonin more than vitamin E more than octreotide in preventing retinal damage by ischemia-reperfusion. All three gave significantprotection against the formation of MDA (10.4+/-2.3, 12.4+/-2.4, 13.9+/-1.5 nmol/100 mg tissue wet weight, respectively) compared to the control (3.7+/-1.3 nmol/100 mg tissue wet weight) and I/R groups (22.7+/-6.2 nmol/100 mg tissue wet weight). CONCLUSIONS: This study demonstrates the inhibitory effect of melatonin, vitamin E and octreotide on MDA levels during retinal ischemia-reperfusion injury.

The protective effects of melatonin, vitamin E and octreotide on retinal edema during ischemia-reperfusion in the guinea pig retina.

PURPOSE: The purpose of this study is to provide evidence that free radical damage is a component of retinal ischemia-reperfusion (I/R) injury, and to determine whether melatonin, vitamin E and octreotide can protect retina from this injury. METHODS: The right eyes of 50 male guinea pigs weighing 500-600 g were used. The animals were randomly assigned to group 1 (control), group 2 (I/R), group 3 (melatonin + I/R), group 4 (vitamin E + I/R) and group 5 (octreotide + I/R). Groups 3, 4 and 5 received four subcutaneous injections at six-hour intervals for total dosage of 10 mg/kg melatonin, 150 mg/kg vitamin E and 22 microg/kg octreotide respectively. The first dose of each substance was administered 5 minutes before retinal ischemia. Retinal ischemia was induced for 1.5 hours, then followed by reperfusion for 24 hours. Infections of all three substances were repeated at 6, 12 and 18 hours during reperfusion. The animals were killed at 24 hours of reperfusion. Sagittal sections of 4 microm were cut and stained with hematoxylin and eosin for light microscopic evaluation. The average thickness (edema) of the inner plexiform layer for each eye was measured in sagittal sections near the optic nerve and expressed in microns. RESULTS: The efficacy of each compound had the following relationships: melatonin>vitamin E>octreotide in preventing retinal damage by ischemia-reperfusion. The mean thickness of the inner plexiform layer was 13.3 +/- 0.8 microm, 25.9 +/- 2. 0 microm, 20.0 +/- 0. 7 microm, 21.6 +/- 0.7 microm, 23.9 +/- 0.8 microm respectively in the control, I/R, I/R plus melatonin, I/R plus vitamin E and I/R plus octreotide groups. The thickness of the inner plexiform layer in group 1 (control) was significantly less than the other groups (p<0.001). The inner plexiform layer was thicker in the I/R group than with I/R plus melatonin, I/R plus vitamin E and I/R plus octreotide (all p < 0.01). The inner plexiform layer was thicker in the I/R plus octreotide group than the I/R plus vitamin E and I.R plus melatonin groups both (p < 0.05). Compared to the I/R plus melatonin group, the inner plexiform layer was significantly thicker in the I/R plus vitamin E group (p < 0. 05). CONCLUSIONS: This study demonstrates a protective effect of melatonin, vitamin E and octreotide on the retina during retinal ischemia-reperfusion injury.

Ultrastructure of human umbilical vessels in pre-eclampsia.

OBJECTIVE: Our objective in this study was to investigate the ultrastructure of endothelial and muscle cells of human umbilical vessels in both normal and pre-eclamptic pregnancies. METHODS: Ten umbilical cords from pre-eclamptic (36, 38 and 40 weeks) and four from normal pregnancies (40 weeks) were collected immediately after vaginal deliveries. Umbilical veins and arteries were isolated and fixed in phosphate-buffered 2.5% glutaraldehyde solution (pH 7.2) for 4 h and postfixed with 1% osmium tetroxide at 4 degrees C for 2 h. The sections were embedded in Araldit CY 212. Ultrathin sections were stained with uranyl acetate, examined and photographed. RESULTS: Human umbilical vessel endothelial cells showed ultrastructural changes in pre-eclamptic patients. Weibel-Palade bodies and some organelles such as rough endoplasmic reticulum were found in increased numbers in venous endothelial cells. Accumulations of granular material were detected under the venous endothelium. CONCLUSION: The endothelial and muscle cells of the umbilical vessels from pregnancies complicated by pre-eclampsia showed morphological changes.

Photodisruptive Nd:YAG laser in the management of premacular subhyaloid hemorrhage.

PURPOSE: Premacular subhyaloid hemorrhage is usually a benign condition that generally improves spontaneously and rarely causes visual loss. However, because the hemorrhage may cause permanent macular changes before it resolves, Nd:YAG laser posterior hyaloidotomy may be indicated in selected cases. This study investigated the effects of drainage of premacular subhyaloid hemorrhage into the vitreous with Nd:YAG laser treatment. METHODS: This study was conducted between February 1996 and March 1999. Six patients had a circumscribed premacular hemorrhage in one eye and were treated with the Nd:YAG laser to drain the blood into the vitreous cavity. The hemorrhage originated from Valsalva retinopathy (2 cases), proliferative diabetic retinopathy (2 cases), central retinal vein occlusion (1 case), and blunt ocular trauma (1 case). The size of the hemorrhage is expressed in disc diameters. RESULTS: The mean pretreatment hemorrhage measured 5.7 disc diameters (range 3.5-8.0). Visual acuity in all cases before laser treatment was hand movement. After laser treatment, the hemorrhage instantly drained into the vitreous cavity, resulting in rapid improvement of vision. Drainage was complete within one week and visual acuity improved dramatically. The mean follow-up was 26.3 months (range 7-42 months). No retinal damage or rebleeding occurred due to the laser treatment, and vitrectomy was not required in any eye. CONCLUSIONS: Nd:YAG laser posterior hyaloidotomy may be useful for draining a premacular hemorrhage into the vitreous cavity in selected cases. To establish this as a routine procedure, a randomized prospective study is needed to compare observation, primary vitrectomy, and Nd:YAG laser treatment.

Large bilateral lateral rectus recession in large angle divergence excess exotropia.

PURPOSE: Classic teaching suggests that surgery for intermittent exotropia should be based on distance/near differences. True divergence excess exotropia should be treated with symmetric lateral rectus recession. The aim of this study was to investigate the effect of large bilateral lateral rectus (LR) recession in large-angle intermittent exotropia. METHODS: Thirty-three consecutive patients with large-angle divergence excess exotropia ranging from 50 to 65 (mean 56.7 +/- 6.3) prism diopters were treated with 8.0 to 9.5 mm (mean 8.8 +/- 0.7 mm) recession of both LR muscles. RESULTS: Successful alignment was achieved in 25 cases (76%) while residual exotropia was seen in eight patients (24%) within the limit of 15 prism diopters. Mean follow-up time was 28.5 +/- 8.4 (range 13 to 38) months. Abduction deficit due to this procedure was not seen in any case. CONCLUSIONS: We conclude that large bilateral LR recession is an appropriate surgical method for large-angle divergence excess exotropia.

Effects of systemic octreotide, local mytomycine-C and local corticosteroids on wound-healing reaction after glaucoma surgery.

PURPOSE: To determine and compare the effectiveness of octreotide, mitomycine-C and corticosteroids on wound-healing reaction after glaucoma surgery. METHODS: A full thickness scleral trephination was carried out by the same surgeon on tour groups of six rabbits. A sponge soaked in mytomicine-C was applied subconjunctivally in group 1 before trephination. Group 2 received corticosteroid drops tid topically for 14 days. Group 3 received subcutaneous octreotide injections tid for 14 days. The control group (group 4) was not given any drug that may interfere with wound healing. All groups received gentamycine drops tid for seven days. The rabbits were Sacrificed on the fourteenth day and the trephination area with overlying conjunctiva was excised. The samples were prefixed with glutaraldehyde, dehydrated and embedded in Araldite Cy 212. Ten semithin sections stained with toluidin blue were analysed for each group. Fibroblast and macrophage counts were performed on the surgical site and subconjunctival area. RESULTS: Intensive fibroblastic activity, increased number of vessels and active macrophages were observed only in group 4. The fibroblast and macrophage densities in this group were significantly higher than the other three groups in which wound healing was modulated (p < 0.001). Mean number of fibroblasts in group 1 was also significantly less than the ones of groups 2 and 3 (p < 0.01). Macrophage densities were similar in groups 1, 2 and 3. No statistical significance was found between groups 2 and 3 by means of fibroblast and macrophage densities. CONCLUSION: Octreotide reduced wound-healing reaction in a similar fashion to corticosteroids or mitomycine-C. These initial results seem promising.