Transition to Chronic Fibrosis in an Animal Model of Retinal Detachment With Features of Proliferative Vitreoretinopathy.

Purpose: Proliferative vitreoretinopathy (PVR) is the most common cause of failure of surgically repaired rhegmatogenous retinal detachment (RRD). Chemically induced and cell injection PVR models do not fully simulate the clinical characteristics of PVR in the post-RRD context. There is an unmet need for translational models in which to study mechanisms and treatments specific to RRD-PVR. Methods: RRD was induced in adult Dutch Belted rabbits. Posterior segments were fixed or processed for RNA sequencing at 6 hours and 2, 7, 14, and 35 days after induction. Histochemical staining and immunolabeling for glial fibrillary acidic protein, alpha smooth muscle actin, vascular endothelial growth factor receptor 2, CD68, and RPE 65 kDa protein were performed, and labeling intensity was scored. Single cell RNA sequencing was performed. Results: Acute histopathological changes included intravitreal and intraretinal hemorrhage, leukocytic vitritis, chorioretinitis, and retinal rarefaction. Chronic lesions showed retinal atrophy, gliosis, fibrotic subretinal membranes, and epiretinal fibrovascular proliferation. Fibrillar collagen was present in the fibrocellular and fibrovascular membranes in chronic lesions. Moderate to strong labeling of glia and vasculature was detected in chronic lesions. At day 14, most cells profiled by single cell sequencing were identified as Mϋller glia and microglia, consistent with immunolabeling. Expression of several fibrillar collagen genes was upregulated in chronic lesions. Conclusions: Histological and transcriptional features of this rabbit model simulate important features of human RRD-PVR, including the transition to chronic intraretinal and periretinal fibrosis. This animal model of RRD with features of PVR will enable further research on targeted treatment interventions.

Zinc Oxide Tetrapods Modulate Wound Healing and Cytokine Release In Vitro-A New Antiproliferative Substance in Glaucoma Filtering Surgery.

Glaucoma filtering surgery is applied to reduce intraocular pressure (IOP) in cases of uncontrolled glaucoma. However, postoperative fibrosis reduces the long-term success of both standard trabeculectomy and microstents. The aim of this study was to test the antiproliferative and anti-inflammatory potential of ZnO-tetrapods (ZnO-T) on human Tenon's fibroblasts (HTFs) for glaucoma surgery. The toxicity of ZnO-T on HTFs was determined using an MTT test. For analysis of fibroblast proliferation, migration, and transdifferentiation, cultures were stained for Ki67, alpha-smooth muscle actin (α-SMA), and p-SMAD. A fully quantitative multiplex ELISA was used to determine the concentrations of different cytokines, platelet-derived growth factor (PDGF), and hepatocyte growth factor (HGF) in culture supernatants with and without previous ZnO-T treatment. Treatment with higher concentrations (10 and 20 µg/mL) was associated with HTF toxicity, as shown in the wound healing assay. Furthermore, the number of Ki67, α-SMA-positive, and pSMAD-positive cells, as well as IL-6 and HGF in supernatants, were significantly reduced following incubation with ZnO-T. In conclusion, we were able to show the antiproliferative and anti-inflammatory potentials of ZnO-T. Therefore, the use of ZnO-T may provide a new approach to reducing postoperative fibrosis in glaucoma filtering surgery.

Metabolic Profiling by GC-MS, In Vitro Biological Potential, and In Silico Molecular Docking Studies of Verbena officinalis.

Verbena officinalis L. is a traditionally important medicinal herb that has a rich source of bioactive phytoconstituents with biological benefits. The objective of this study was to assess the metabolic profile and in vitro biological potential of V. officinalis. The bioactive phytoconstituents were evaluated by preliminary phytochemical studies, estimation of polyphenolic contents, and gas chromatography-mass spectrometry (GC-MS) analysis of all fractions (crude methanolic, n-hexane, ethyl acetate, and n-butanol) of V. officinalis. The biological investigation was performed by different assays including antioxidant assays (DPPH, ABTS, CUPRAC, and FRAP), enzyme inhibition assays (urease and α-glucosidase), and hemolytic activity. The ethyl acetate extract had the maximum concentration of total phenolic and total flavonoid contents (394.30 ± 1.09 mg GAE·g-1 DE and 137.35 ± 0.94 mg QE·g-1 DE, respectively). Significant antioxidant potential was observed in all fractions by all four antioxidant methods. Maximum urease inhibitory activity in terms of IC50 value was shown by ethyl acetate fraction (10 ± 1.60 µg mL-1) in comparison to standard hydroxy urea (9.8 ± 1.20 µg·mL-1). The n-hexane extract showed good α-glucosidase inhibitory efficacy (420 ± 20 µg·mL-1) as compared to other extract/fractions. Minimum hemolytic activity was found in crude methanolic fraction (6.5 ± 0.94%) in comparison to positive standard Triton X-100 (93.5 ± 0.48%). The GC-MS analysis of all extract/fractions of V. officinalis including crude methanolic, n-hexane, ethyl acetate, and n-butanol fractions, resulted in the identification of 24, 56, 25, and 9 bioactive compounds, respectively, with 80% quality index. Furthermore, the bioactive compounds identified by GC-MS were analyzed using in silico molecular docking studies to determine the binding affinity between ligands and enzymes (urease and α-glucosidase). In conclusion, V. officinalis possesses multiple therapeutical potentials, and further research is needed to explore its use in the treatment of chronic diseases.

Flexural Strength of Dental Fiber Composite Post Manufactured with a Novel Approach.

Thermoplastic resin fiber composites have an easy fabrication process, good mechanical properties, and compatible stiffness to tooth dentin. However, they have not yet attracted much interest in the field of dentistry. The current study was carried out to test a new proposed approach to manufacture a fiber reinforced composite endodontic post and evaluate its flexural strength through a two-point inclined loading test. The proposed fiber post manufacture approach depends upon a braiding technique of the glass fibers' (GF) reinforcing component with thermoplastic polypropylene (PP) resin fibers that will later represent the resin matrix after thermal melting. Posts were made of different core (70%) and sheath (30%) construction (PP/GF ratios) using three different GF types and seizing pre-treatment to both fiber types. Two-point inclined loading test at 45 °C applied force angle was used to test the posts' flexural strength. Fiber posts (1.6 mm in diameter) with pure GF (de-sized starch E-GF and pre-silanized S-GF) core, and sheath construction with higher PP/GF ratios, showed the significantly highest two-point bending strength (56.67 ± 4.89 and 53.96 ± 1.81 MPa, respectively), among experimental posts groups (except for the commercial control posts). However, posts with PP core type showed the lowest values (21.59 ± 1.86 and 16.54 ± 1.94 MPa for de-sized and E-glass sheath fibers, respectively). Based on these findings, the proposed approach was reliable in producing fiber-reinforced composite post with the desired dimensions and fiber distribution. Post construction with a pure GF core and higher PP/GF ratio showed considerably higher flexural strength and GF volume fraction comparable to commercial available post types.

Braiding Thermoplastic and Glass Fibers in Composite Dental Post Improves Their Mechanical Compatibility, In Vitro Experiment.

Mechanical compatibility with the human dentin is a considerable issue when fabricating dental fiber posts. To this purpose, this study introduces a new method of fabricating compatible dental posts using braiding techniques of thermoplastic fibers (matrix) with glass fibers (reinforcement). Fifty fiber-reinforced composite (FRC) posts of thermoplastic yarns polypropylene (PP) braided with continuous filaments glass fibers (GFs) for reinforcement, varying in fiber volume fraction (FVF), and core types are fabricated and tested. Posts are performed using a braiding machine, and braids are placed in an aluminum mold. The filled mold is playced inside an oven at the melting temperature of the polypropylene to produce the final post's shape. An ultrasonic test is conducted to measure the shear modulus and Young's modulus of FRC post specimens by measuring the velocities of both the P-wave and S-wave. In order to ensure the accuracy of the measurements, each sample is measured three times, and then the means and standard deviations of each sample are calculated before analyzing the test results using the means of two steps, namely, clustering and comparing the P and R² values of each cluster, which revealed that FVF, fiber mass, and core type of the specimen had a significant effect on the resulted Young's and shear modulus. The results indicate that the proposed method can fabricate competitive dental posts with regard to different fabricating variables. The samples show Young's modulus ranges of from 10.08 GPa to 31.83 GPa. The following tested hypothesis is supported: the braiding technique of thermoplastic fibers with glass fibers will improve the mechanical compatibility of the resulting posts (ex vivo).

Metabolite secretions of Lactobacillus plantarum YYC-3 may inhibit colon cancer cell metastasis by suppressing the VEGF-MMP2/9 signaling pathway.

BACKGROUND: Colorectal cancer (CRC) is a major clinical challenge, and the gut microbiome plays important roles in the occurrence and metastasis of CRC. Lactobacillus and their metabolites are thought to be able to suppress the growth of CRC cells. However, the antimetastatic mechanism of Lactobacillus or their metabolites toward CRC cells is not clear. Therefore, the aim of this study was to assess the inhibitory mechanism of cell-free supernatants (CFSs) of L. rhamnosus GG, L. casei M3, and L. plantarum YYC-3 on metastasis of CRC cells. RESULTS: YYC-3 CFS showed the highest inhibitory effect on CRC cell growth, invasion and migration, and inhibited MMP2, MMP9, and VEGFA gene and protein expression, and protein secretion. Furthermore, it suppressed the activities of MMPs by gelatin zymography. Moreover, the effective compounds in these CFSs were analyzed by Q Exactive Focus liquid chromatography-mass spectrometry. CONCLUSIONS: Our results showed that metabolite secretions of YYC-3 may inhibited cell metastasis by downregulating the VEGF/MMPs signaling pathway. These data suggest that treatment of CRC cells with metabolites from L. plantarum YYC-3 may reduce colon cancer metastasis.

Probiotic strain Lactobacillus plantarum YYC-3 prevents colon cancer in mice by regulating the tumour microenvironment.

The gut microbiota plays important roles in chronic inflammation and colon cancer. Lactobacillus is a gut-resident probiotic with benefits to host health. We recently identified Lactobacillus plantarum strain YYC-3 with strong inhibition against two colon cancer cell lines (HT-29 and Caco2). However, the inhibitory effect of YYC-3 against colon cancer in vivo has not been verified. Thus, in the present study, we explored the probiotic function of strain YYC-3 and its cell-free supernatant (YYCS) respectively in the APCMin/+ mouse model of colon cancer during tumour development and growth, and the underlying anti-cancer mechanism. Treatment of both strain YYC-3 and the YYCS prevented the occurrence of colon tumours and mucosal damage in APCMin/+ mice fed a high-fat diet, although YYC-3 had a stronger anti-cancer effect. The mechanism involved modulation of the immune system and downregulated expression of the inflammatory cytokines interleukin (IL)-6, IL-17 F, and IL-22, along with reduced infiltration of inflammatory cells. Moreover, YYC-3 suppressed activation of the NF-κB and Wnt signalling pathways, and restored the altered gut microbiota composition to closely match that of wild-type mice. These results lay a theoretical foundation for application of YYC-3 in colon cancer prevention.

CD147 and matrix-metalloproteinase-2 expression in metastatic and non-metastatic uveal melanomas.

BACKGROUND: Extracellular matrix remodelling regulated by matrix-metalloproteinase (MMP) inducer (CD147) is a crucial process during tumor cell invasion and regulation of blood supply. In this study, we evaluated the correlation of CD147 and MMP-2 expression with major prognostic factors for uveal melanoma and the development of metastasis. METHODS: The expression of CD147 and MMP-2 was analyzed in 49 samples of uveal melanomas. Triple immunofluorescence stainings using markers against glial cells (GFAP), endothelial cells (CD34) and macrophages (CD68) were performed to further analyse the exact localisation of CD147 and MMP-2 positivity. In 28 cases clinical metastatic disease were found. The remaining 21 cases showed no signs of metastatic disease for an average follow-up of 10 years. Correlation analysis (Pearson correlation) was performed to analyse the association of CD147 and MMP-2 expression with known prognostic factors, vasculogenic mimicry (VM), the mature vasculature (von Willebrand Factor) and tumor induced angiogenesis (by means of Endoglin expression). RESULTS: CD147 and MMP-2 were expressed in 47 (96.0 %) of the uveal melanomas. CD147 up-regulation was significantly correlated with a higher MMP-2 expression. The overall expression analysis revealed no significant difference in the metastatic (p = 0.777) and non-metastatic subgroup (p = 0.585). No correlation of CD147 expression and any system of blood supply was evident. In the non-metastatic sub-group a significant correlation of clustered CD147 positive cells with largest basal diameter (p = 0.039), height (p = 0.047) and TNM-stage (p = 0.013) was evident. CONCLUSIONS: These data may indicate that CD147 regulates MMP-2 expression in uveal melanoma cells.

Analysis of caveolin-1 and phosphoinositol-3 kinase expression in primary uveal melanomas.

BACKGROUND: To evaluate the regulation of blood supply in primary uveal melanomas through caveolin-1 (Cav-1)/phosphoinositol-3 kinase (PI3K). METHODS: The expression of Cav-1 and PI3K was analysed in 51 paraffin sections of metastatic (n = 30) and non-metastastic uveal melanomas (n = 21). Two trained observers quantified Cav-1 and PI3K immunofluorescensce expression by determining intensity of staining and percentage of positive cells. The expression was correlated with known prognostic factors. Besides angiogenesis by means of endoglin expression, the normal vasculature (von Willebrand Factor expression) was evaluated semi-quantitatively. Vasculogenic mimicry (VM) was analysed by CD31/PAS staining. RESULTS: All examined specimens expressed Cav-1 with a mean of 90.34% Cav-1 positive cells (range, 3.23-100%). Metastatic disease was associated with a higher Cav-1 expression. The correlation of Cav-1 with well-established prognostic factors showed a significant association between Cav-1 expression and largest tumour diameter (P = 0.022), tumour node metastasis classification (P = 0.008) and invasion of optic nerve head (P = 0.048). PI3K was expressed by all uveal melanomas with a mean of 87.28% cells showing PI3K expression. A higher level of PI3K was significantly associated with larger height (P = 0.042) and progressed tumour node metastasis stage (P = 0.016). The percentage of PI3K and Cav-1 positive cells were significantly associated (P = 0.034). For PI3K and Cav-1 expression a non-significant association with VM was shown (P = 0.064 and P = 0.072, respectively). No correlation of PI3K or Cav-1 with angiogenesis or mature vasculature was seen (P > 0.05). CONCLUSIONS: Cav-1 expression may be especially up-regulated in larger uveal melanomas. As it was correlated with PI3K expression and VM in this series of uveal melanoma, Cav-1 might induce the formation of VM via the PI3K-signalling cascade.

Serum cytokines as biomarkers for age-related macular degeneration.

PURPOSE: This study evaluates the potential of serum pro-inflammatory cytokines as AMD biomarkers. METHODS: Serum samples from 30 age-related macular degeneration (AMD) patients and 15 age-matched controls were examined for 16 inflammatory cytokines using multiplex ELISA. Patients were divided into three subgroups (improvement/no change/deterioration during anti-VEGF treatment) by OCT and funduscopy, and correlated to the cytokine levels. RESULTS: Serum concentrations of IL-1α, IL-1ß, IL-4, IL-5, IL-10, IL-13, and IL-17 were significantly higher in AMD patients than in controls. None of the co-variables expressed a significant effect on the tested cytokines. Only IL-1a and IL-17 showed a statistically significant difference between groups (improved, unchanged, deteriorated) as determined by one-way ANOVA. Patients with increased macular thickness during treatment showed significantly lower levels of IL-17 compared to improved cases and to unchanged cases (p = 0.004, 0.03 respectively, Dunnett's T3 post hoc multiple test). TNF-α was significantly higher in improved cases compared to deteriorated cases (p =0.03, Dunnett's T3 post hoc multiple test). IL-17 was a significant predictor for macular oedema using linear regression (ß = -0.888, p <0.05). CONCLUSION: Elevation of IL-1α, IL-1ß, IL-4, IL-5, IL-10, IL-13, and IL-17 in the serum of AMD patients supports the hypothesis of AMD as an inflammatory disease. Patients with high IL-17 and TNF-α serum levels were more likely to have a favourable course under VEGF therapy. These cytokines may be used as easy-to-obtain biomarkers.

A p38 MAPK inhibitor improves outcome after glaucoma filtration surgery.

PURPOSE: The aim of this study is to explore the effects of SB 202190, a highly selective p38 MAPK inhibitor, on bleb survival following glaucoma filtering surgery. MATERIALS AND METHODS: Human Tenon's fibroblasts were treated with SB 202190 (0 to 100 µM) to determine IC50, and cell proliferation and migration. Twenty rabbits were divided into 4 groups (G1-G4): G1 animals received only a trabeculectomy. G2-G4 animals had trabeculectomy plus one of the following subconjunctival adjuvants, given intraoperatively and postoperatively: G2=sham, G3=20 µM SB 202190, and G4=50 µM SB 202190. The blebs were assessed using the Indiana Bleb Appearance Grading Scale. The intraocular pressure (IOP) was expressed as the right to left eye ratio (R/L ratio). For morphometric bleb analysis the JMicrovision software was used. RESULTS: SB 202190 inhibits human Tenon's fibroblasts proliferation and migration in vitro (IC50=17.2 µM). In vivo subconjunctival application of SB 202190 after glaucoma filtration surgery significantly increases bleb height, bleb extension, and bleb survival time compared with the control. In all groups, the IOP ratio correlates with the fibrotic process. G3 shows a significantly reduced IOP ratio at day 14 compared with the control. Analysis of the bleb histology shows that G3 has a significant smaller fibrosis area compared with G1 and G2. Application of the highest dose (50 µM SB 202190) is associated with hyphema in 2 of 5 animals (40%). CONCLUSION: Application of SB 202190 significantly improves bleb characteristics and IOP control after filtering glaucoma surgery in a rabbit model.

Ranibizumab as adjuvant in the treatment of rubeosis iridis and neovascular glaucoma--results from a prospective interventional case series.

BACKGROUND: To evaluate the capability of adjuvant intraocular ranibizumab (Lucentis) injections in the treatment of rubeosis and intraocular pressure in patients with rubeosis and neovascular glaucoma. METHODS: Ten eyes with rubeosis (R) and ten eyes with neovascular glaucoma (NVG) received Lucentis injections (ranibizumab 0.5 mg/0.05 ml) in this prospective, monocenter, 12-months, interventional case series. The primary efficacy outcome measure was the change of degree of iris rubeosis as documented by iris fluorescein angiography measured after 12 months. Secondary outcomes were intraocular pressure (IOP), best-corrected visual acuity (BCVA, logMAR), numbers of additional interventions or antiglaucoma medications administered after injection, the gonioscopic status of the anterior chamber angle, and central retinal thickness. RESULTS: In the R group, 3.6 injections and in the NVG group 2.3 injections of Lucentis were administered. Additional treatments were photocoagulation (n = 19), cyclodestructive procedures (n = 9), cryopexy (n = 3), and vitrectomy (n = 1). The mean stage of rubeosis was 3.4 ± 0.7 in the R group and 3.6 ± 0.8 in the NVG group at baseline. At month 12, the rubeosis was almost resolved in the R group (0.1 ± 0.3, p < 0.001), and decreased significantly in the NVG group (0.7 ± 1.1, p < 0.001). In the NVG subgroup, mean IOP was 41.4 ± 13.4 mmHg at baseline, which decreased rapidly (18.2 ± 12.3, day-14, p = 0.005) and stabilized during the follow-up (15.6 ± 2.0 mmHg, p < 0.05). BCVA improved significantly in both groups (p < 0.05, at month 12). CONCLUSIONS: Injection of 0.5 mg ranibizumab appears to be beneficial as an adjuvant treatment in neovascular glaucoma and rubeosis due to its anti-angiogenic properties and its ability to prevent establishment or progression of anterior chamber angle obstruction. Conventional therapeutic procedures addressing the retinal ischemia are still required in a stage-wise treatment approach.

Morphological and functional outcome after brilliant blue G-assisted macular hole surgery.

PURPOSE OF THE STUDY: To investigate the outcome of brilliant blue G (BBG)-assisted internal limiting membrane peeling in macular hole surgery after a follow-up of 6 months. PROCEDURES: In this retrospective study 20 eyes have been treated with BBG-assisted macular hole surgery. After a follow-up of 6 months, the functional and anatomical outcomes have been analyzed. RESULTS: The mean preoperative best-corrected visual acuity (BCVA) was 0.7 logMAR units (mean ± SD 0.66 ± 0.27). After 3 months, the mean BCVA increased not significantly to 0.4 (0.54 ± 0.30), but a significant improvement to 0.2 logMAR units (0.28 ± 0.23) could be detected after 6 months compared to baseline (p < 0.01). Primary macular hole closure after a single surgery was found in 17 of 20 eyes. CONCLUSION AND MESSAGE: BBG exhibits sufficient staining qualities and safety profile leading to a significant functional improvement after successful macular hole surgery.

The novel use of decorin in prevention of the development of proliferative vitreoretinopathy (PVR).

BACKGROUND: The cytokine transforming growth factor-ß (TGF-ß) is a pivotal contributor to tissue fibrosis and a key cytokine in the pathogenesis of cellular transdifferentiation, epithelial-mesenchymal transition (EMT), and cell adhesion. This study evaluates the effect of decorin, a naturally occurring TGF-ß inhibitor, in an experimental rabbit model for proliferative vitreoretinopathy (PVR). METHODS: Traumatic PVR was induced in 50 rabbits divided into ten groups (n = 5). One group (GI) reveals a control with no treatment after trauma. Groups (GII-GIV) consisted of subgroups receiving phacovitrectomy at three different time points; (a) at the time of trauma, (b) 1 week following trauma, and (c) 2 weeks following trauma. GIII and GIV received 100 µg or 200 µg decorin, respectively. PVR severity was scored from 0 to 4. The amount of fibrosis was quantified using JMicroVision© software. RESULTS: The control group GI developed severe PVR with tractional retinal detachment (TRD); (PVR score ≥2) in four rabbits out of five. Vitrectomy had a positive effect (p < 0.05) on PVR development when preformed immediately, however the developed fibrosis was high. The best results were obtained when surgery was used in conjunction with decorin that reduced both the PVR score and fibrosis development significantly (p < 0.05). Depending on dosage and time of vitrectomy, PVR could be completely avoided (PVR score = 0) in 16 rabbits out of 30. TRD was prevented in 13 rabbits out of 15 in GIII to 14 rabbits out of 15 in GIV. In decorin-treated eyes, vitrectomy outcome was best when preformed at 1 week after trauma. There were no drug-related toxic effects evident on clinical and histopathological examination. CONCLUSIONS: In conclusion, in this rabbit model of PVR, adjuvant decorin application during vitrectomy effectively reduces fibrosis and TRD development. In conjunction with no obvious histopathological toxicity signs, decorin represents a promising substance to inhibit PVR reactions.

Expression of c-Kit and its ligand SCF in primary uveal melanoma.

PURPOSE: To evaluate the concurrent rate of expression of c-Kit and its ligand stem cell factor (SCF) in uveal melanoma in respect to the further clinical course and the correlation of these markers. METHODS: Paraffin sections from 35 primary uveal melanomas were evaluated immunohistochemically for the expression of c-Kit and SCF. Sixteen cases developed systemic metastasis during the follow-up (median: 5 years after diagnosis). The patients who did not develop metastasis (n = 19) had a mean follow-up of 10.6 (9-13) years. Radiation was performed in 6 patients. RESULTS: c-Kit and SCF were expressed in all patients who did or did not develop metastasis in the further clinical course. A mean SCF expression of 77.2% (range 52.7%-97.5%) of tumors that did not develop systemic metastasis and 30.1% (range 2.9%-61.5%) of tumors with systemic metastasis were evident. Uveal melanomas revealing an increased SCF expression were found to develop no metastasis more frequently (p<0.0001; hazard ratio (HR) = 0.963, 95% confidence interval (CI) 0.945-0.981). A mean c-Kit expression of 58.01% (range 5.9%-97.9%) in the group who did not develop metastasis and 48.9% (range 5.0%-95.9%) in the group with systemic metastasis were observed. c-Kit expression was not associated with increased rates of metastasis formation (p = 0.7329; HR = 0.997, 95% CI 0.982-1.013). The correlation between SCF and c-Kit is weak (0.39; 95% CI 0.06-0.63). CONCLUSIONS: c-Kit expression was not found to be associated with metastasis formation. A high SCF expression of primary choroidal melanomas was significantly associated with a lower incidence of systemic metastasis, which indicated SCF as a benign prognostic factor in the further clinical course.

The effect of adjuvant dimethylenastron, a mitotic Kinesin Eg5 inhibitor, in experimental glaucoma filtration surgery.

BACKGROUND: The aim of the study was to analyze the effect of Dimethylenaston, a mitotic kinesin 5 (Eg5) inhibitor, in an experimental setting of glaucoma filtration surgery. METHODS: On 37 chinchilla rabbits (ChBBCH), glaucoma filtration surgery similar to clinical practice, was performed. The animals received either no adjuvant, one unilateral subconjunctival injection of Dimethylenastron (1.0 µmol, 3.0 µmol), or the vehicle alone at baseline and in two further groups additionally at days 3 and 7 thereafter (1.0 µmol, 3.0 µmol). The evaluation of antifibrotic efficacy was performed by clinical response, histological examination, and immunohistochemical staining for smooth muscle actin (SMA) and CD 31. The animals were sacrificed on day 14, and the eyes processed for histology. RESULTS: The vehicle was well tolerated. Except for two cases of transient fibrinous reaction after the injection of 3.0 µmol Dimethylenastron, no adverse effects, such as inflammation or blurring of the optical media, were observed. A bleb scarring occurred in the group that received surgery only, adjuvant DMSO, or Dimethylenastron 3.0 µmol. Dimethylenastron (1.0 µmol) induced a milder scarring compared with the control group but the length of bleb survival was not significantly prolonged (p = 0.053, Kaplan-Meier log rank test). In all groups, the intraocular pressure correlated with the fibrotic process and reached normal levels within 14 days after surgery. Those groups injected with 1.0 µmol Dimethylenastron revealed a significantly reduced ratio of intraocular pressure and a milder, but not sufficiently reduced, subconjunctival fibrotic reaction according to the histological and immunohistochemical analysis. CONCLUSIONS: The subconjunctival administration of Dimethylenastron 1.0 µmol induced a milder conjunctival scarring. The applied concentrations of Dimethylenastron did not improve the surgical outcome of glaucoma filtration treatments in rabbits sufficiently.

Effects of pegaptanib sodium on retinal function in isolated perfused vertebrate retina.

PURPOSE: To evaluate the short-term toxic effects of pegaptanib sodium on retinal function. At present, intraocular anti-vascular endothelial growth factor (VEGF) therapy is the primary choice of treatment for neovascular maculopathy. The isoform VEGF(165) is specifically inhibited by pegaptanib sodium. Therefore, since VEGF(165) has neuroprotective effects against apoptosis of neuronal cells, blockage of VEGF(165) by pegaptanib could induce retinal dysfunction. In the present study, we used an electrophysiological technique for testing retinal toxicity in order to evaluate the short-term toxic effects of pegaptanib sodium on retinal function in a model of isolated perfused vertebrate retina. METHODS: Isolated bovine retinas were perfused with an oxygenated, pre-incubated nutrient solution. Electroretinograms (ERGs) were recorded as trans-retinal potentials using Ag/AgCl electrodes. Pegaptanib sodium (0.006, 0.06, or 0.2 mg/ml) and solvent carrier were added to the nutrient solution for 45 min. ERGs were monitored before, during, and after exposure. RESULTS: No significant reductions of b-wave (p = 0.357, p = 0.31, and p = 0.11, respectively) or a-wave (p = 0.189, p = 0.46, and p = 0.23, respectively) amplitudes were detected during application of pegaptanib (0.006, 0.06, or 0.2 mg/ml). The solvent carrier alone had no effect on ERG b- or a-waves (p = 0.98 and p = 0.42, respectively). During washout, ERG amplitudes of all test series remained unchanged. CONCLUSION: Results suggest that both pegaptanib sodium and its solvent carrier have good safety profiles. Intraocular application of 0.3 mg pegaptanib sodium induced no significant changes in ERGs in our ex vivo model and, thus, appears to be safe.

Possible implications of MCAM expression in metastasis and non-metastatic of primary uveal melanoma patients.

PURPOSE: To evaluate the expression of melanoma cell adhesion molecule (MCAM) as prognostic factor in uveal melanoma patients. METHODS: Paraffin sections from 35 primary uveal melanomas were analyzed immunhistochemically for the expression of MCAM. Further known prognostic factors such as cell type, ciliary body invasion, tumor stage, and local extension were evaluated. In 16 cases, patients had developed metastatic disease. The patients without metastasis (n = 19) had a mean follow-up of 10.6 (9-13) years. RESULTS: All tumors were positive for MCAM (mean: 57.05%). In the group without metastasis, an average MCAM expression of 35.37% (SD 19.66%) compared to 82.78% (SD 11.73%) in the metastasis group was found. The Cox regression analysis showed a significant association of an enhanced MCAM expression and death due to metastasis (HR: 365.48, 95% CI: 18.51, 7217.85). CONCLUSION: MCAM expression of primary uveal melanomas can serve as a possible prognostic parameter for metastasis. If further experiments approve the cellular adhesion molecules to account for early micrometastasis of tumor cells, a possible target might be available for future treatment.