Assessment of endothelial cell density and corneal thickness in corneal grafts an average of 5 years after penetrating keratoplasty

BACKGROUND Corneal transparency is a useful indicator for corneal function. Our aim was to investigate central corneal endothelial cells and corneal thickness in transplanted corneas at an average of 5.4 years after penetrating keratoplasty PATIENTS AND METHODS The study involved 68 perforated keratoplasty patients with at least a 1 year follow-up. Post-operatively, the central corneal endothelial layer was observed using a contact specular microscope. Central endothelial cell density, corneal thickness and the coefficient of variation of endothelial size were statistically analysed. RESULTS The post-operative follow-up time was ranging from 12 months to 23 years. Endothelial cell density (ECD) was 1,501 ± 249 cell/mm(2). The average cell size was 673.6 ± 98.3 μm(2), and the coefficient of variation of cell size was 0.61 ± 0.11. No difference in ECD was detected between diagnostic groups. Corneal thickness was 0.56 ± 0.06 mm. Correlation between ECD and post-operative time was not significant (r = 0.02; p = 0.85). CONCLUSION Our study concluded that ECD showed a higher rate of decrease after penetrating keratoplasty with no relation to pre-operative diagnosis

Ophthalmological Manifestations and Tear Investigations in Systemic Sclerosis

Systemic sclerosis (SSc) is a chronic autoimmune disorder characterized by widespread small vessel vasculopathy, immune dysregulation with production of autoantibodies, and progressive fibrosis. There are only few reports available concerning ophthalmological complications in the course of SSc, although ocular manifestations, e.g., dry eye syndrome (DES), occurs frequently and decreases the quality of life of these patients. Vascular endothelial growth factor (VEGF), the major pro-angiogenic factor, plays a key role in the pathomechanism of SSc. Although elevated levels of VEGF in sera have already been demonstrated, VEGF analysis in tears of patients with SSc has not been performed in previous studies. VEGF in the tears of patients with SSc was found to be decreased by 20%, compared to healthy controls. The reason why the VEGF levels are not elevated in the tears of patients with SSc needs further investigations, as does the sera of the same patients. The cytokine array results revealed a shift in the cytokine profile characterized by the predominance of inflammatory mediators. Our current data depict a group of cytokines and chemokines, which play a significant role in ocular pathology of SSc; furthermore, they might function as excellent candidates for future therapeutic targets in SSc with ocular manifestations

A survey of corneal changes caused by daily wear silicone hydrogel contact lenses

Purpose: The examination of the effects of second generation lotrafilcon B silicone hydrogel (SiH) lenses on the cornea when worn for three years of daily wear. Material and Methods: 55 healthy patients were divided into two groups: current hydrogel contact lens wearers refitted with lotrafilcon B lenses (Group 1; 28 patients) and neophyte contact lens wearers (Group 2; 27 patients). Each patient's subjective eye comfort was measured with a self-administered questionnaire. The corneas were analyzed using contact specular microscope to measure corneal thickness and the endothelium before the SiH lenses were fitted after four weeks, one month, six months, one year, two years, and three years of lens wear. Results: Subjective complaints of patients in Group 1 were reduced; however patients in Group 2 experienced discomfort during the first two to four weeks of use. In Group 1, objective examinations identified a decrease in endothelial cell density. In Group 2, the endothelial cell density increased slightly in the first two years but decreased after three years. The results indicate that lotrafilcon B slows down the deleterious effects of contact lenses. The coefficient of variation significantly decreased after six months in Group 1 (0.47 vs 0.44; p = 0.049), whereas, in Group 2, the hexagonal cells improved significantly after one month (27.78 vs 28.25; p = 0.025). Conclusion: Based on the subjects involved and the period of time under examination, it can be concluded that high-Dk SiH lenses support the physiological metabolism and functions of the cornea by improving oxygen provision

Production of benzylisoquinoline alkaloids in Saccharomyces cerevisiae

The benzylisoquinoline alkaloids (BIAs) are a diverse class of metabolites that exhibit a broad range of pharmacological activities and are synthesized through plant biosynthetic pathways comprised of complex enzyme activities and regulatory strategies. We have engineered yeast to produce the key intermediate reticuline and downstream BIA metabolites from a commercially available substrate. An enzyme tuning strategy was implemented that identified activity differences between variants from different plants and determined optimal expression levels. By synthesizing both stereoisomer forms of reticuline and integrating enzyme activities from three plant sources and humans, we demonstrated the synthesis of metabolites in the sanguinarine/berberine and morphinan branches. We also demonstrated that a human P450 enzyme exhibits a novel activity in the conversion of (R)-reticuline to the morphinan alkaloid salutaridine. Our engineered microbial hosts offer access to a rich group of BIA molecules and associated activities that will be further expanded through synthetic chemistry and biology approaches

A Wide Spectrum of Ocular Manifestations Signify Patients with Systemic Sclerosis

Objectives: Systemic sclerosis (SSc) is a rare, chronic connective tissue disease involving multiple organ systems, including the eye. We evaluated the detailed clinical ocular manifestations of outpatients with SSc. Methods: Demographics, disease duration and subtype, nailfold capillaroscopy (NFC) patterns and laboratory parameters encompassing the autoantibody profile of 51 SSc patients were evaluated, and a general ocular examination was performed for each participant. Results: Twenty-nine patients (56.86%) had eyelid skin alterations, 26 (50.98%) had retinal abnormalities, 26 (50.98%) had cataracts, 8 (15.69%) had conjunctival changes, 7 (13.73%) had iris abnormalities, 33 (64.71%) suffered from dry eye disease (DED), and 11 (21.57%) suffered from glaucoma. Significant positive correlations were found between NFC data and both tear breakup time and Ocular Surface Disease Index test values. Conclusions: Eyelid skin abnormalities, DED and retinal abnormalities are among the most common SSc-related ocular involvements. Diverse ophthalmic findings are attributed to the heterogeneity of SSc

Corneal Manifestations of Inflammatory Bowel Disease

Purpose: To evaluate detailed corneal parameters of inflammatory bowel disease (IBD) patients, including Crohn’s disease (CD) and ulcerative colitis (UC) patients, and to assess associations between anterior segment values and other clinical variables. Methods: This prospective cross-sectional case-control study at a tertiary referral center included 30 CD patients, 36 UC patients and 80 age- and gender-matched controls with no ocular symptoms or ocular surface disorders. All study participants underwent a comprehensive ophthalmological evaluation with special interest in dry eye disease (DED). Corneal parameters were evaluated by Pentacam. Results: The mean age of CD patients, UC patients, and controls was 45.80 ± 11.55 years, 52.00 ± 16.05, and 50.68 ± 14.62, respectively. The average disease duration was 12.72 ± 5.83 years for CD patients and 15.94 ± 10.09 years for UC patients. All pachymetric (center, apex and thinnest) and corneal volume (CV) measurements were significantly decreased, while anterior chamber angle width (ACA) values were significantly increased on both sides in all IBD patients compared to those in controls (p < .05). In addition, several anterior segment parameters were altered unilaterally in CD or UC patients. Negative correlations were found between corneal parameters and Schirmer I test values. Conclusions: Our investigations suggest that IBD patients have thinner corneas compared to that of controls. The coexistence of reduced tear quantity seems to have an additional impact on the thinning of the cornea in IBD patients. Early recognition of corneal impairments, a possible extraintestinal manifestation of IBD, should be included in the disease checkup to reduce vision-threatening developments