COMPARISON OF THE CHOROIDAL VASCULARITY INDEX MEASUREMENTS OF IMAGES ACQUIRED WITH DIFFERENT OPTICAL COHERENCE TOMOGRAPHY SCAN SCALE TYPES.

PURPOSE: To evaluate the differences in choroidal vascularity index (CVI) measurements between images acquired at the 1:1 pixel scale and at the 1:1 µ m scale of the Heidelberg optical coherence tomography device. METHODS: Forty-five healthy eyes of 45 healthy subjects were included for this study. Fovea-centered scans were obtained with an enhanced-depth imaging mode with a high-speed protocol scan. Each scan was exported in 3 different types: 1) 1:1 pixel scale type; 2) 1:1 µ m scale type (MST); and 3) 4×-magnified MST (4×MST; 400%-magnified 1:1 µ m images exported via screenshot). A comparison between CVI measurements based on the different scale types of optical coherence tomography images was conducted using the Bland-Altman analysis and intraclass correlation coefficient. RESULTS: The image with the worst clarity was acquired via the MST, and the CVI was found to be higher in MST images (69.05 ± 3.21) compared with the other groups. The intraclass correlation coefficient between the CVI values of the 4×MST and pixel scale type images was 0.92, between those of the 4×MST and MST images was 0.33, and between those of the pixel scale type and MST images was 0.44. CONCLUSION: The optical coherence tomography scale and export method type significantly influence the image resolution, CVI, and choroidal area measurements.

Preventive effects of Capparis Spinose extract on experimental periodontitis in rats: a histopathological and biochemical study.

This study aimed to assess the effectiveness of Capparis Spinose (CS) in preventing the initiation and progression of experimental periodontitis and to evaluate the effect of its on systemic oxidative stress in rats by experimental periodontitis model. Twenty-four male rats were equally divided into; Ligatured (L), non-ligatured (NL), and Ligatured with CS (11 days/day per 20 mg/kg) (LC) groups. Experimental periodontitis was induced with the silk suture technic. Alveolar bone loss was examined, and total antioxidant capacity(TAOC), total oxidant status(TOS), and oxidative stress index(OSI) were analyzed in rat serum. Although; alveolar bone loss showed statistically significant lower values in the LC group compared to L (p < 0.05), not NL. In the LC group, osteoclast and osteoblast numbers were statistically significant compared to L, but there were no statistical differences between LC and NL. Serum TAOC levels were significantly lower in group L compared to others and also LC group showed significant differences from NL. TOS and OSI levels were significantly higher in group L than in other groups. Within the limitation of the present study, it can be said that the destruction via local inflammation that may occur after the experimental periodontitis can be prevented by using CS.

MicroRNA-626 inhibits mTOR pathways activity of retinal pigment epithelial cells by targeting SLC7A5 in human ARPE-19 Cells.

Recent studies have shown that miRNAs are associated with the pathological process involved in age-related macular degeneration (AMD). However, the microRNA-mediated post-transcriptional regulation in human retinal pigment epithelium (RPE) cells has not been adequately investigated. We investigated how miR-626 inhibits mTOR activity pathways and pathway-related genes in retinal pigment epithelial cells by targeting the solute carrier family seven-member 5 (SLC7A5) in ARPE19 cells.    We transfected mir-626 mimic, mir-626 inhibitör and siRNA in human retinal pigment epithelial cell line was examined using RT-PCR and western blot, respectively. We knocked down mir-626 levels and overexpression by mir-626-siRNA transfection of human RPE cell lines, and using an MTT assay, we assessed the role of SLC7A5 on RPE cell proliferation. We additionally measured the expression of mTOR, Akt1, caspase 3, Bax, SLC17A7, SLC17A8, Creb1, Pten, HIF1A, HIFI. The findings demonstrate that mir-626 inhibits SLC7A5 gene expression and proliferation of ARPE-19 cells. Short interfering RNA (siRNA) mediated suppression of SLC7A5, a predicted target of mir-626, has the same effect on ARPE-19 cells. We identified how miR-626 causes apoptosis and macula degeneration in RPE cells by targeting SLC7A5 through the mTOR signaling pathway. miR-626 was an essential regulator of the expression of the Slc7a5 gene. Importantly, we determined that miR-626 is essential to play a role in AMD. This research project shows that SLC7A5 is a direct target of mir-626 in ARPE-19 cells for the first time.

HENLE FIBER LAYER THICKNESS AND AREA MEASUREMENT IN TYPE 2 DIABETES MELLITUS WITH AND WITHOUT RETINOPATHY USING A MODIFIED DIRECTIONAL OPTICAL COHERENCE TOMOGRAPHY STRATEGY.

PURPOSE: To investigate the thicknesses and areas of Henle fiber layer (HFL), outer nuclear layer, and outer plexiform layer in the eyes of patients with diabetes with no diabetic retinopathy, in eyes with nonproliferative diabetic retinopathy without diabetic macular edema, and in healthy eyes using a modified directional optical coherence tomography strategy. METHODS: In this prospective study, the no diabetic retinopathy group included 79 participants, the nonproliferative diabetic retinopathy group comprised 68 participants, and the control group had 58 participants. Thicknesses and areas of Henle fiber layer, outer nuclear layer, and outer plexiform layer were measured on a horizontal single optical coherence tomography scan centered on the fovea using directional optical coherence tomography. RESULTS: The foveal, parafoveal, and total HFL were significantly thinner in the nonproliferative diabetic retinopathy group than in the no diabetic retinopathy group and the control group (all P < 0.05). The no diabetic retinopathy group had significantly thinner foveal HFL thickness and area compared with the control group (all P < 0.05). The nonproliferative diabetic retinopathy group had significantly thicker outer nuclear layer thickness and area in all regions than the other groups (all P < 0.05). The outer plexiform layer measurements did not differ between the groups (all P > 0.05). CONCLUSION: Directional optical coherence tomography provides isolated thickness and area measurement of HFL. In patients with diabetes, the HFL is thinner, and HFL thinning begins before the presence of diabetic retinopathy.

HoLEP after prostate biopsy: does it have any impact?

PURPOSE: Holmium laser enucleation of the prostate (HoLEP) has recently become the recommended treatment for prostate in all sizes in benign prostate hyperplasia surgery. A recent prostate biopsy performed prior to the HoLEP procedure can make surgeons concerned about the surgery. We aimed to investigate the per- and postoperative outcomes of the HoLEP procedure in patients who underwent prostate biopsy and to evaluate the most appropriate surgery time after biopsy. METHODS: The data of 160 patients who underwent HoLEP by a single surgeon between March 2017 and December 2019 were retrospectively reviewed. The patients were divided into two groups, Group 1 consisted of 80 patients without prostate biopsy and Group 2 consisted of 80 patients with prior prostate biopsy. All HOLEP procedures in group 2 were performed at least 2 weeks following biopsy. Per- and postoperative outcomes, complications were evaluated. RESULTS: No significant differences were found between groups in terms of by enucleation time, efficiency of laser, efficiency of enucleation, hospitalization time, and catheterization removal time. Only morcellation time was shorter in biopsy naïve patients. There were no statistical differences in postoperative outcomes. Previous prostate biopsy did not affect the continence status in our study group. There were not any Clavien grade 4 or higher complications. Urinary tract infection was higher in early post-biopsy period, there was no difference among the groups. CONCLUSiON: Our study confirms that HoLEP is a safe and efficient surgical procedure for the patients with prior prostate biopsy. We believe that it can be safely performed 2nd week following prostate biopsy.

Evaluation of the protective effects of non-thermal atmospheric plasma on alveolar bone loss in experimental periodontitis.

OBJECTIVES: The inhibition of bone destruction is one of the main goals of periodontitis treatment. The aim of this study was to investigate the protective effects of non-thermal atmospheric plasma (NTAP) on alveolar bone loss radiographically, histomorphometrically, and histologically in experimental periodontitis in rats. MATERIALS AND METHODS: A total of twenty-eight rats were randomly divided into three groups: control group (CG) (n = 8), periodontitis group (PG) (n = 10), and NTAP group (NTAPG) (n = 10). In PG and NTAPG, experimental periodontitis was created with ligating. The kINPen 11 plasma jet was applied around the ligatured teeth in NTAPG. The samples from each group were radiographically assessed with microcomputed tomography (micro-CT); then, histological (presence of osteoclasts and inflammatory cells) and immunohistochemical (immunoreactive of OCN and ALP) findings were compared. RESULTS: The results revealed a significant increase in alveolar bone loss in the PG compared with CG and NTAPG (p < 0.05). Inflammation, alveolar resorption, and cement damage were reduced significantly in the group treated with NTAP compared to the PG (p < 0.05). Significantly higher levels of osteoclasts were detected in the PG in comparison with both CG and NTAPG (p < 0.05). The lowest osteocalcin and ALP values were determined in PG, and the differences between PG and both groups were also significant (p < 0.05). CONCLUSION: Within the limitations of the present study, we can say that NTAP may enhance the bone remodeling process by inhibiting inflammation and preventing alveolar bone destruction. CLINICAL RELEVANCE: NTAP has clinical potential for accelerating and treating periodontitis with the inflammatory response modulation, osteoblast differentiation, and alveolar bone loss reduction.

Regional analysis of segmented-macular structure in patients with myopic anisometropia.

PURPOSE: To compare intraretinal layers between the eyes in patients with myopic anisometropia, and evaluate the relationship between the layers with spherical equivalent (SE) and axial length (AL). METHODS: In this retrospective study, the more myopic (MM) and fellow (F) eyes of 41 patients with myopic anisometropia, and 38 emmetropic (± 0.50 diopter) control (C) eyes were inclueded. Intraretinal layer segmentation was performed by optical coherence tomography. Global volumes of retinal layers and their thicknesses in nine macular regions were compared. Correlation analysis was used to determine the relationship with SE and AL in each layer. RESULTS: Total retinal, ganglion cell (GCL), inner nuclear (INL), and outer plexiform (OPL) layer volumes in MM eyes were less than in C eyes, while INL and OPL were less than in F eyes. There was no difference in the fovea, except for the retinal pigment epithelium. In MM eyes, only INL and OPL were thin in at least one perifoveal and parafoveal quadrant compared to F eyes. Only INL and OPL thicknesses were significantly correlated with both SE and AL in all perifoveal quadrants. In contrast to the thinning found in MM eyes, the only layer in which thickening was detected to compare to C eye was nerve fiber layer (NFL), which correlated positively with SE and negatively with AL. CONCLUSION: While the fovea is less affected by myopia, thinning becomes remarkable in the perifoveal quadrants. Despite thinning in many layers, especially INL and OPL, NFL thickening may be seen due to myopia.

Effects of 1,25 Dihydroxyvitamin D3 on Human Retinal Pigment Epithelial Cell Lines.

PURPOSE: To assess the effects of 1,25 dihydroxyvitamin D3 (vitamin D3) either alone or under oxidative damage on human retinal pigment epithelium cell lines. METHODS: The human retinal pigment epithelial cell lines were pretreated with hydrogen peroxide with different concentrations (100-1000 µM) and durations (4, 12 and 24 h) to determine the appropriate dose. A group of cells were treated with vitamin D3 alone, and another group of cells were co-treated with different concentrations of (10-100 nM) vitamin D3 and hydrogen peroxide. Anti-cytotoxic, anti-apoptotic and anti-genotoxic effects of vitamin D3 on the hydrogen peroxide treated cell line were evaluated. In addition, mitochondrial membrane potentials of treated cell lines were measured. RESULTS: Vitamin D3 showed statistically significant anti-cytotoxic effects and increased cell viability in all concentrations (p < 0.001). It has also significantly decreased the intracellular ROS generation at concentrations between 10-60 nM and increased intracellular reactive oxygen species in high doses over 90 nM (p < 0.01). When apoptosis was evaluated, vitamin D3 caused statistically significant decrease in a dose-dependent manner (p < 0.001). In terms of DNA damage which was caused by oxidative stress, it was observed that vitamin D3 significantly reduced the damage in a dose-dependent manner (p < 0.001). At the doses of 10-50 nM, vitamin D3 significantly decreased the mitochondrial membrane potential (p < 0.01). CONCLUSION: Our study suggests that 1,25 (OH)2 D3 is capable for alleviating the oxidative damage in ARPE cell lines. With these results, vitamin D is thought to be a therapeutic alternative for the prevention of age-related macular degeneration. This warrants further investigations.

Spectral domain optical coherence tomography classification of diabetic macular edema: a new proposal to clinical practice.

PURPOSE: To classify the types of diabetic macular edema (DME) and evaluate its morphological features on spectral domain optical coherence tomography (SD-OCT) and determine correlations between visual acuity and OCT findings. METHODS: We assessed 406 eyes of 309 patients with a diagnosis of DME retrospectively. Three types based on SD-OCT were identified: diffuse macular edema, cystoid macular edema, and cystoid degeneration. Morphological features such as serous macular detachment (SMD), vitreomacular interface abnormalities (VMAI), hard exudates, photoreceptor status, and correlations between visual acuity and those morphological features were also evaluated by SD-OCT. RESULTS: The most common type of DME was cystoid edema (68.5%). No statistically significant difference was found between groups in sex (P = 0.40), type of diabetes (P = 0.50), or diabetic retinopathy (P = 0.78). However, the duration of symptoms and BCVA was significantly lower in the group with cystoid degeneration compared with the group with cystoid edema (P < 0.001) and the group with diffuse macular edema (P < 0.001). In the group with cystoid degeneration compared with the groups with cystoid and diffuse edema, the central fovea and central subfield were significantly thicker (both (P < 0.001), the subfoveal choroid was significantly thinner (P = 0.049), rate of serous macular detachment was significantly lower (P < 0.001), and the rate of outer retinal damage was significantly higher (P < 0.001). CONCLUSIONS: Cystoid macular degeneration, which is consistent with poor functional and morphological outcomes, should be differentiated from cystoid macular edema. Serous macular detachment, which is mostly seen in eyes with early stages of DME, should be evaluated as an accompanying morphological finding rather than a type of DME.

Fluorescein angiography as a primary guide for reduced-fluence photodynamic therapy for the treatment of chronic central serous chorioretinopathy.

PURPOSE: The aim of this study is to investigate the results of fluorescein angiography (FA)-guided reduced-fluence photodynamic therapy (PDT) in the treatment of chronic central serous chorioretinopathy (CSCR), with the hypothesis that indocyanine green angiography (ICGA) guidance is avoidable in some cases. METHODS: This retrospective study includes a consecutive nonrandomized series of chronic CSCR cases. All eyes were examined with FA and the ones that had discrete active leakage areas or points had undergone reduced-fluence PDT. RESULTS: The study included 45 eyes of 41 patients with a mean age of 48.8 ± 10.7. The main duration of last chronic CSCR episode was 13.0 ± 11.9 months. Thirty-nine (86.7%) out of 45 consecutive eyes had active leakage area(s) on FA, which enabled them to be treated with PDT. Remaining six eyes had undergone ICGA examination and had received an ICGA-guided PDT. In FA-guided eyes, the mean BCVA improved from 0.44 ± 0.25 Snellen lines to 0.63 ± 0.32 lines in the last control visit (p < 0.001). Both central macular thickness and subfoveal choroidal thickness decreased significantly in treated eyes. Thirty-eight eyes (97.4%) in FA-guided group and six eyes (100.0%) in ICGA-guided group had total resorption of subretinal fluid. CONCLUSION: This study provides basis to support the hypothesis that FA-guided half-fluence PDT may be justified as an alternative method of treatment in appropriate cases of chronic CSCR without compromising the therapeutic success.

Three new circulating microRNAs may be associated with wet age-related macular degeneration.

This study investigates the circulating microRNA (miRNA) expression profiles in patients with age-related macular degeneration (AMD) and the role of miRNA in wet AMD and its pathways. Exosomes were extracted from serum samples of AMD patients (n = 70) and a control group (n = 50). After isolating miRNA from the exosomes, miRNAs were transformed into cDNA. In the control and AMD samples, the expression was compared with a panel including 175 genes using the PCR array method. Target genes and pathways of miRNAs were detected by KEGG and Biocarta signaling pathway enrichments. Comparing the serum samples between groups revealed that the expression levels of 15 microRNAs within 175 genes had significantly changed. In the validation studies, miR-129-3p and miR-132-3p had no significant expression in AMD group compared to the controls. miR-486-5p and miR-626 had higher expression in AMD patients compared to the control group, while miR-885-5p showed significantly lower expression. Pathway analysis revealed that these miRNAs may have critical roles in the apoptosis and neovascularization pathways. The data suggest that some miRNAs within the serum may have a role in the pathogenesis of wet AMD. Further studies are needed to examine the use of these miRNAs as biomarkers.

Evaluation of xenon, light-emitting diode (LED) and halogen light toxicity on cultured retinal pigment epithelial cells.

OBJECTIVE: To compare the possible toxic effects of three light sources used in vitreoretinal endoillumination systems; halogen, xenon, and light-emitting diode (LED) on retinal pigment epithelium (RPE) cell cultures, after two different exposure times. MATERIAL AND METHODS: ARPE-19 human RPE cell cultures were exposed to halogen, xenon, and LED light sources at a distance of 1.5 cm for 30 and 60 min with equal lumen output levels. Cells in the control group were not exposed. RPE cell cultures were compared in terms of cell viability, DNA damage, apoptosis rate, and IL-1ß, IL-6, and TNF- α levels. RESULTS: The halogen light group showed significantly more DNA damage, higher TNF-α, IL-1ß, and IL-6 levels, and lower viable cell count at 30 min compared to the control group. The rates of early and late apoptosis were also significantly higher at 60 min. There were no statistically significant differences in any of the parameters between the xenon and LED light sources and the control group at 30 or 60 min. CONCLUSION: New generation lights, xenon, and LED, seem to be safe in terms of RPE cells. Halogen light may cause toxic effects on RPE cells when used for a long time with maximal power output.

The Utility of Diffusion-Weighted Imaging and Perfusion Magnetic Resonance Imaging Parameters for Detecting Clinically Significant Prostate Cancer.

INTRODUCTION: To establish the diagnostic performance of the parameters obtained from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging at 3T in discriminating between non-clinically significant prostate cancers (ncsPCa, Gleason score [GS] < 7) and clinically significant prostate cancers (csPCa, GS ≥ 7) in the peripheral zone. MATERIALS AND METHODS: Twenty-six male patients with peripheral zone prostate cancer (PCa) who had undergone 3T multiparametric magnetic resonance imaging (MRI) scan prior to biopsy were included in the study and evaluated retrospectively. The GS was obtained by both standard 12-core transrectal ultrasound guided biopsy and targeted MRI-US fusion biopsy and then confirmed by prostatectomy, if available. For each confirmed tumour focus, DCE-derived quantitative perfusion metrics (Ktrans, Kep, Ve, initial area under the curve [AUC]), the apparent diffusion coefficient (ADC) value, and normalized versions of quantitative metrics were measured and correlated with the GS. RESULTS: Ktrans had the highest diagnostic accuracy value of 82% among the DCE-MRI parameters (AUC 0.90), and ADC had the strongest diagnostic accuracy value of 87% among the overall parameters (AUC 0.92). The combination of ADC and Ktrans have higher diagnostic performance with the area under the receiver operating characteristic curve being 0.98 (sensitivity 0.94; specificity 0.89; accuracy 0.92) compared to the individual evaluation of each parameter alone.The GS showed strong negative correlations with ADC (r = -0.72) and normalized ADC (r = -0.69) as well as a significant positive correlation with Ktrans (r = 0.69). CONCLUSION: The combination of Ktrans and ADC and their normalized versions may help differentiate between ncsPCa from csPCa in the peripheral zone.

The Effect of Single-Dose Intraperitoneal Bevacizumab on Peritoneal Adhesion Formation.

BACKGROUND: Intra-abdominal adhesions and their complications following abdominal surgery are serious problems, with an incidence of 67-93%. Prevention of peritoneal adhesion formation may eliminate the need for surgical intervention, decreasing complications, morbidity, and cost. Bevacizumab is a recombinant monoclonal antibody which specifically binds vascular endothelial growth factor, an important cytokine in adhesion formation, and neutralizes its biological activity. We developed an experimental model in rats to determine the effect of bevacizumab in preventing adhesion formation and analyzed its effect both micro- and macroscopically. METHODS: We used 32. Wistar rats randomly divided into two groups: Group A (control) and Group B (bevacizumab), with 16 rats each. A modified cecum abrasion model was developed; 0.9% NaCl solution was administered intraperitoneally to Group A and bevacizumab to Group B. On day 15, adhesion formation was evaluated both macro- and microscopically. RESULTS: Both micro- and macroscopic adhesion grades in Group B were significantly lower than those of control Group A; macroscopic grades were 2.69 ± 0.95 and 0.69 ± 0.8, and microscopic grades were 2.25 ± 1.06 and 0.5 ± 0.52 for Groups A and B, respectively. CONCLUSIONS: Bevacizumab was effective in preventing intraperitoneal adhesion formation in our study; however, its inhibitory effects on embryogenesis and the hematopoietic, endocrine, and immune systems may limit its clinical use.

A novel tool reflecting the role of oxidative stress in the cataracts: thiol/disulfide homeostasis.

We investigated serum and aqueous humor thiol/disulfide (T-D) homeostasis in patients with cataracts versus healthy controls. In total, 56 patients with cataracts and 49 healthy controls were enrolled in this case-control study. Serum total thiol (TT), native thiol (NT), and disulfide (DS) concentrations were determined using a novel automated measurement method. Additionally, DS/TT, DS/NT and NT/TT percentage ratios were compared between the groups. In comparison with the control group, serum NT levels and aqueous humor TT and NT levels were significantly lower (p < .05, p < .05 and p < .001, respectively), whereas serum and aqueous humor DS levels were significantly higher in cataract patients (p < .01 and p < .001). DS/TT and DS/NT ratios were significantly higher and the NT/TT ratio was lower in cataract patients in serum (p < .005) and aqueous humor samples (p < .001). In conclusion, serum T-D homeostasis may be useful as biochemical markers, indicating the role of oxidative stress in the development of cataracts. Further studies are needed to confirm the pathophysiological role of T-D homeostasis in cataractogenesis.

Systemic effects of H2S inhalation at human equivalent dose of pathologic halitosis on rats.

OBJECTIVES: Halitosis is composed by hundreds of toxic gases. It is still not clear whether halitosis gases self-inhaled by halitosis patients cause side effects. The aim of the study was to investigate the effect of H2S inhalation at a low concentration (human equivalent dose of pathologic halitosis) on rats. MATERIALS AND METHODS: The threshold level of pathologic halitosis perceived by humans at 250 ppb of H2S was converted to rat equivalent concentration (4.15 ppm). In the experimental group, 8 rats were exposed to H2S via continuous inhalation but not the control rats. After 50 days, blood parameters were measured and tissue samples were obtained from the brain, kidney and liver and examined histopathologically to determine any systemic effect. RESULTS: While aspartate transaminase, creatine kinase-MB and lactate dehydrogenase levels were found to be significantly elevated, carbondioxide and alkaline phosphatase were decreased in experimental rats. Other blood parameters were not changed significantly. Experimental rats lost weight and became anxious. Histopathological examination showed mononuclear inflammatory cell invasion in the portal areas, nuclear glycogen vacuoles in the parenchymal area, single-cell necrosis in a few foci, clear expansion in the central hepatic vein and sinusoids, hyperplasia in Kupffer cells and potential fibrous tissue expansion in the portal areas in the experimental rats. However, no considerable histologic damage was observed in the brain and kidney specimens. CONCLUSIONS: It can be concluded that H2S inhalation equivalent to pathologic halitosis producing level in humans may lead to systemic effects, particularly heart or liver damage in rats.

Comparison of serum thiol-disulphide homeostasis and total antioxidant-oxidant levels between exudative age-related macular degeneration patients and healthy subjects.

PURPOSE: The purpose of the study was to calculate serum total oxidant status (TOS), total antioxidant status (TAS), and dynamic thiol-disulphide (T-D) homeostasis in patients with age-related macular degeneration (AMD), and compare the results with healthy individuals. METHODS: Thirty-three exudative AMD patients and 33 healthy controls were included in this case-control study. Participants' serum TAS and TOS levels were measured. In addition, total thiol (TT), native thiol (NT), and disulphide (DS) concentrations were assessed using a novel automated method of measurement. RESULTS: In comparison with the control group, serum TAS, TT, and NT levels were found to be significantly lower (p < 0.0001, p = 0.004, p = 0.003, respectively) and TOS levels were detected higher (p = 0.032) in AMD patients. Serum DS levels were elevated in the AMD patient group, but the difference was not statistically significant (p = 0.219). DS/TT and DS/NT ratios were significantly higher (p = 0.012, p = 0.013, respectively) in AMD patients. A positive correlation was found between TT and NT (p < 0.0001) in AMD group. CONCLUSIONS: Serum TOS levels are higher, TAS levels are lower, and the T-D balance is shifted to the DS bond side in AMD patients. These results suggest that increased oxidative stress and decreased antioxidant levels may play a role in AMD progression. Further studies are needed to confirm the pathophysiologic role of T-D homeostasis in AMD.

LONG-TERM OUTCOMES OF RADIAL OPTIC NEUROTOMY FOR MANAGEMENT OF OPTIC DISK PIT MACULOPATHY.

PURPOSE: To evaluate the long-term outcomes of radial optic neurotomy (RON) in patients with optic disk pit maculopathy and to compare the functional and anatomical outcomes of pars plana vitrectomy (PPV) with temporal side single RON versus PPV without RON. METHODS: This retrospective study included 15 eyes of 15 consecutive patients who had surgery for optic disk pit maculopathy. Patients were followed for 12 to 115 months after surgery. Anatomical and functional results were evaluated with optical coherence tomography, MP-1 microperimetry in the central 20°, and measurement of best-corrected visual acuity. Descriptive statistical methods, Friedman chi-square test, post hoc Dunn test, Mann-Whitney test, Wilcoxon signed-rank test, and Fisher's exact test were used to determine the best-corrected visual acuity and MP-1 microperimetry differences between time points and to compare the results between the two treatment groups. RESULTS: Two male and 5 female patients with a mean age 23.3 ± 8.7 (±standard error) years at presentation had PPV and silicone oil or gas tamponade with RON. Best-corrected visual acuity did not deteriorate after the operation in any of the eyes, and improved in 6 (86%) eyes (3 ± 2 lines). After surgery, complete resolution of fluid in the central macula was observed in 6 (86%) eyes. Five male and 3 female patients with a mean age 28.2 ± 8.2 years at presentation had PPV, posterior vitreous detachment, with or without juxtapapillary laser treatment, and silicone oil or gas tamponade. Best-corrected visual acuity did not deteriorate after the operation in any of the eyes, and improved in 5 (62.5%) eyes (2 ± 0.7 lines). After surgery, fluid in the central macula resolved completely in 4 (50%) eyes. CONCLUSION: Pars plana vitrectomy with temporal side, single RON seems to be an effective method of managing optic disk pit maculopathy. The anatomical and functional improvements, without additional treatment or complication during the follow-up period, indicate that RON might be an alternative treatment approach to PPV alone for optic disk pit maculopathy.

Ultrastructural changes in epithelial cells of rats exposed to low concentration of hydrogen sulfide for 50 days.

Hydrogen sulfide (H2S) and other volatile sulfur compounds (VSCs) appear mainly in the oral air of patients with halitosis. It seems that VSCs are directly involved in the pathogenesis of gingival diseases. In previous studies, short-term (7 hours-4 days), high concentrations (5-400 ppm) of H2S applications on periodontal tissues have been evaluated in a culture medium. The aim of the present study was to investigate the potential effects of lower (equivalent to halitosis) concentrations of H2S on rat gingival tissue for longer-term inhalation. The threshold level of pathologic halitosis perceived by humans at 250 ppb of H2S was converted to rat equivalent concentration (4.15 ppm). Rats in the experimental (H2S) group (n=8) were exposed to H2S continuously but not the control rats (n=8). After 50 days, the gingival sulcular tissue samples of each rat were taken and examined using transmission electron microscope. Ultrastructural changes in the sulcular epithelia of the rat gingiva showed deformation of celullar shape, vacuolization, and disintegrity of intercelullar connection by loss of desmosomes and collagen fibrils. No basal membrane damage was observed. Inhalation of low levels of H2S (equivalent of halitosis) in the oral environment causes ultrastructural celullar damages in rat sulcular mucosa. These results suggest that halitosis may be the potential reason for periodontal destruction in humans.

The Effects of Nigella Sativa Seed Extract on Bone Healing in an Experimental Model.

The purpose of this study was to histologically evaluate the effects on bone healing of nigella sativa seed extract applied on calvarial defects in an ovariectomized rat model. The study included 32 female rats weighing 280 to 310 g with an average age of 3 months. A defect was created with a trephine burr on each rat calvarium. The rats were divided into 2 groups (control and study) of 8 animals each. All the defects were grafted with a gelatin sponge mixed with normal saline. In the study group, nigella sativa seed extract was applied systemically using an oro-gastric tube. Half of the animals in each group were sacrificed after 2 weeks, and the others after 4 weeks. In the control groups, the defects were not completely filled with regenerated bone. Osteoblast cells were observed more in the study groups. A higher rate of osteoclasts was determined in the control groups. In addition, the nigella sativa group had a statistically greater amount of bone formation than the others group at both 2 weeks and 4 weeks (P <0.05). The systemic application of nigella sativa seed extract demonstrated incredibly positive effects on enhanced bone healing in this experimental osteoporotic model.