Impact of the COVID-19 pandemic's first wave on the care and treatment situation of intravitreal injections in a German metropolitan region.

PURPOSE: This study aims to evaluate the impact of the first coronavirus 2019 (COVID-19) wave in 2020 on patients scheduled for intravitreal injections (IVI) in a German metropolitan region. METHODS: We performed a multicentre prospective survey and retrospective analysis of the records of patients treated with intravitreal injections during the 20-week period from March to July 2020 in all four hospital eye departments in the city of Hamburg using a questionnaire (on treatment adherence, SarsCoV2-related personal, familial and social data) and treatment data. RESULTS: A total of 1038 patients (2472 IVI, 1231 eyes) and 818 questionnaires were evaluated. Longer duration of therapy, lower visual acuity (VA) of the treated and higher VA of the fellow untreated eye was were associated with a higher probability of visit cancellation. Every additional year of life posed a 2.6% lower risk of noncompliance. A COVID-19 infection in the family environment displayed a 5.5-fold chance of visit cancellation. Patients treated for neovascular age-related macular degeneration (nAMD) had a 36% reduced risk of visit cancellation compared to patients with diabetic macular oedema (DME). CONCLUSION: A long preceding treatment period, low VA of the treated eye, high VA of the untreated eye, COVID-19 in the family and DME were identified as risk factors for IVI visit cancellations during the COVID-19 pandemic. Compliance to treatment might be improved in the future by taking these risk factors into account when scheduling patients for IVI during the exceptional circumstances of a pandemic.

Transactivation of lifeguard (LFG) by Akt-/LEF-1 pathway in MCF-7 and MDA-MB 231 human breast cancer cells.

Lifeguard (LFG) has been identified as a molecule that uniquely inhibits death mediated by Fas. The molecular function of human LFG and its regulation in carcinogenesis is uncertain. In our study, we investigated the potential regulation of LFG expression by Akt/LEF-1 pathway. The Glycogen synthase kinase-3 (GSK3) can be regulated by different signaling pathways including those mediated by protein kinase Akt. Inhibition of GSK3beta subunits activity results in the stabilisation of the beta-catenin protein and its accumulation in the nucleus, where it associates with members of the TCF/LEF-1 family of transcription factors to mediate gene transcription. In Western blots, RT-PCR and by small interfering RNA directed against LEF-1, we demonstrated that LFG expression correlates with GSK3beta and LEF-1 activation. Moreover, we showed that LFG mRNA was down-regulated after transfection with siRNA against LEF-1 in MDA-MB-231 cells. Our results therefore identify LFG as a target of the Akt/LEF-1 pathway in MDA-MB-231 breast tumour cells, a regulation which could play a key role in breast tumour progression.

The anti-apoptotic protein lifeguard is expressed in breast cancer cells and tissues.

Lifeguard (LFG) is an anti-apoptotic protein that inhibits Fas-mediated death in tumour cells. However, the molecular function of human LFG in the carcinogenesis of human breast cells is uncertain. We studied the expression and function of endogenous LFG in four breast cancer cell lines (MCF-7, MDA-MB-231, T-47D and HS 578T), a human breast epithelial cell line (HS 578Bst), and in healthy and cancerous breast tissues. Molecular (Western blot and RT-PCR) and immunohistochemical techniques were used to investigate the LFG expression. To investigate the breast cancer cell proliferation in the presence of Fas, we performed fluorescent cell viability assays. The possible association of Fas with LFG was analyzed by immunofluorescence microscopy. In this paper, we provide convincing evidence that LFG is overexpressed in several human breast cancer cell lines. More importantly, we found that the LFG expression correlates with high tumour grades in primary breast tumours. Finally, we demonstrated that Fas sensitivity is reduced in breast cancer cell lines expressing LFG. Our results indicated that LFG is strongly expressed in breast cancer epithelial cells. Moreover, the overexpression of LFG correlated with tumour grade and reduced Fas sensitivity. Our findings support the idea that LFG may have a role in the downregulation of apoptosis in breast cancer cells.

Endothelial Cell Count in Eye Bank Corneal Grafts: Impact of Death Cause and Donor Diseases.

PURPOSE: The purpose of this study is to analyze the impact of death causes and documented donor diseases on initial endothelial cell counts (after retrieval) and the development of corneal graft endothelia during organ culture. METHODS: The retrospective statistic analyses was conducted on a data set of 10,185 human corneas prepared at the Hamburg Eye Bank. RESULTS: Although we observed that death by gunshot trauma or alcoholism seems to be associated with marginally higher endothelium cell counts (independently from donor age), we could prove that only donor age is a relevant predictive parameter for the initial cell-density of the endothelium and its development in vitro. CONCLUSION: We conclude that an extension of prospective quality parameters for donor selection additional to donor age (such as individual causes of death) is not necessary.

Thirty years of cornea cultivation: long-term experience in a single eye bank.

PURPOSE: To evaluate donor demographics, trends in donor tissue procurement and tissue storage over a long period. METHODS: A retrospective, longitudinal, descriptive analysis was undertaken of data from the Hamburg Eye Bank Data Base (HEB-DB) that had been collected between 1981 and 2010. Data on 54 parameters of cornea donors [including clinical history, age, death cause, gender and death-to-explantation interval (DEI)] and of cultivated corneas (endothelial quality and development in culture, cultivation period, microbiological contamination) were retrieved. These data were analysed statistically, focusing on the historical development of the eye bank. RESULTS: At the time of retrieval (June 2010), the HEB-DB contained data on 10 943 corneas (5503 donors). Most donors were men (65%) and had died from cardiopulmonary (n = 801)/cerebral (n = 261) failure or as the result of a polytraumatic accident/suicide (n = 602). Within these years, donor age, DEI and storage time increased. The percentage of stored corneas suitable for transplantation displayed a variable but increasing trend; in 2007, almost 75% of the stored corneas were transplanted. Between 1995 and June 2010, the median microbiological contamination rate was 5.3%. A change in the procurement procedure from enucleation to corneoscleral explantation in 2008 led to a briefly increased contamination rate. CONCLUSION: Donor demographic data run parallel to the general demographic development. Our analysis indicates a dynamic development of the eye bank over the last 30 years and emphasizes the need for an active quality management in coping with the challenges of modern eye banking.

Risk factors for donor cornea contamination: retrospective analysis of 4546 procured corneas in a single eye bank.

PURPOSE: Microbiological contamination is a common cause for elimination of organ-cultured donor corneas. The aims of the present study were to analyze contamination rates and identify risk factors for contamination. METHODS: Retrospectively, the contamination rates of 4546 organ-cultured corneas and the causative species were studied. The impact of sex, age, death-to-explantation interval, explantation technique, cause of death, and mean monthly temperature on contamination rate was analyzed. RESULTS: The median annual contamination rate was 5.3% (range: 3%-19%). Most contaminations were of fungal origin (61.9%), with Candida species (45%) being predominant. Bacterial contaminations (34.4%) were dominated by Staphylococcus species (12.8%). Sex, donor age, and mean monthly temperature had no statistically significant influence on the contamination rate. The median death-to-explantation interval of contaminated corneas (44 hours) was longer than that of sterile corneas (39 hours; P < 0.001; n = 4437). Cardiopulmonary failure was associated with the highest contamination rate (13.6%) of all death causes. The switch from whole globe to in situ excision was followed by a temporary increase in contamination rate (12.5%-19.4%). CONCLUSIONS: Although the genesis of donor cornea contamination seems to be multifactorial, resident species from physiological skin flora are the main contaminants indicating that the donor corpses could be the main source of microbiological contamination. A change in the explantation technique was followed by an increase in the contamination rate.

Microcarrier-based expansion of adult murine side population stem cells.

The lack of reliable methods to efficiently isolate and propagate stem cell populations is a significant obstacle to the advancement of cell-based therapies for human diseases. One isolation technique is based on efflux of the fluorophore Hoechst 33342. Using fluorescence-activated cell sorting (FACS), a sub-population containing adult stem cells has been identified in a multitude of tissues in every mammalian species examined. These rare cells are referred to as the 'side population' or SP due to a distinctive FACS profile that results from weak staining by Hoechst dye. Although the SP contains multi-potent cells capable of differentiating toward hematopoietic and mesenchymal lineages; there is currently no method to efficiently expand them. Here, we describe a spinner-flask culture system containing C2C12 myoblasts attached to spherical microcarriers that act to support the growth of non-adherent, post-natal murine skeletal muscle and bone marrow SP cells. Using FACS and hemocytometry, we show expansion of unfractionated EGFP⁺ SP cells over 6 wks. A significant number of these cells retain characteristics of freshly-isolated, unfractionated SP cells with respect to protein expression and dye efflux capacity. Expansion of the SP will permit further study of these heterogeneous cells and determine their therapeutic potential for regenerative and reparative therapies.

Traumatic wound dehiscence after penetrating keratoplasty: case series and literature review.

PURPOSE: Blunt trauma after penetrating keratoplasty (PK) is a high risk for wound rupture at the donor-recipient interface. We present 6 cases of traumatic wound dehiscence after PK; we describe the morphologic and functional outcome after surgical intervention and provide a review of the current literature. METHODS: Six patients with a traumatic wound dehiscence after PK were analyzed retrospectively from the files of the University Eye Hospital Hamburg-Eppendorf (1998-2009). In addition, a comprehensive literature review was performed. RESULTS: The indications for PK were keratoconus, corneal scars, and Fuchs endothelial dystrophy. The age range was 22-81 years; the time span between PK and globe rupture was 1 month to 27 years. The cause of the dislocation was a fall or blunt trauma, through a branch, airbag, fist, or finger. The corrected distance visual acuity (CDVA) pretrauma ranged between hand movement and 20/32. The CDVA after wound repair was 20/400 to 20/25 depending on the severity of the trauma. In 3 of the 6 cases, visual rehabilitation was superior to the pretrauma vision, whereas in 3 cases the pretrauma CDVA could not be reached. CONCLUSIONS: If a timely and adequate treatment of the traumatically dislocated transplant can be given, it is likely that the transplant will survive. Nevertheless, severely reduced visual acuity (i.e., < hand movement) and lens damage at the time of trauma are the most reliable predictors for the final visual outcome. A permanent loss of visual acuity is related rather to the intraocular damage (vitreous loss, vitreous bleeding, retinal tears, and retinal detachment) than to the readapted transplant itself.

Relationship between minimum corneal thickness and refractive state, keratometry, age, sex, and left or right eye in refractive surgery candidates.

PURPOSE: To evaluate the relationship between the thinnest point in corneal thickness and the refractive state, keratometry, age, sex, and the ocular side. SETTING: Eye clinics in Germany and Austria and the Department of Ophthalmology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. DESIGN: Cross-sectional study. METHODS: Medical records of refractive surgery candidates from 2006 to 2010 were reviewed. Univariate variance analysis, covariance analysis, Bravis-Pearson correlations, Spearman rank correlations, and t tests were performed to analyze the relationship between the thinnest point in corneal thickness and the biometric parameters. RESULTS: The study evaluated 4600 eyes. The mean thinnest point in corneal thickness was 549 µm ± 33 (SD). Refractive state, mean keratometry, and age had a statistically significant impact on the thinnest point in corneal thickness. The mean thinnest point in corneal thickness was 548 ± 33 µm in myopia, 555 ± 34 µm in hyperopia, and 553 ± 35 µm in high astigmatism, with a statistically significant difference between hyperopic eyes and myopic eyes (P<.001). No correlation was found between the thinnest point in corneal thickness and sex or ocular side. Refractive state (r = 0.07, P<.001) and age (r = 0.05, P<.001) showed a positive correlation and keratometry (r = -0.09, P<.001) a negative correlation with the thinnest point in corneal thickness. CONCLUSIONS: Refractive state, mean keratometry, and age had a statistically significant, although marginal impact, on the thinnest point in corneal thickness. Sex and the ocular side had no effect.

Bilateral crystalline corneal deposits as first clinical manifestation of monoclonal gammopathy: a case report.

AIMS: To report the clinical and diagnostic findings of a patient with bilateral corneal deposits caused by an underlying monoclonal gammopathy. METHODS: Slit-lamp biomicroscopy, confocal microscopy and additional serological tests were performed on a 35-year-old man presenting with bilateral crystalline corneal deposits. RESULTS: The patient was diagnosed as having monoclonal gammopathy based on elevated levels of serum immunoglobulin G. Confocal microscopy showed highly reflective (protein) deposits throughout the entire cornea, with the highest density in the epithelium and anterior stromal keratocytes. CONCLUSIONS: Monoclonal gammopathy, a potential sign of a life-threatening disease, can lead to dense, bilateral corneal deposits. As such changes can occur long before ocular or systemic discomforts appear, an early diagnosis is crucial. Ophthalmologists should be aware of corneal deposits as potential warning signs of monoclonal gammopathy.

Cardiac conduction through engineered tissue.

In children, interruption of cardiac atrioventricular (AV) electrical conduction can result from congenital defects, surgical interventions, and maternal autoimmune diseases during pregnancy. Complete AV conduction block is typically treated by implanting an electronic pacemaker device, although long-term pacing therapy in pediatric patients has significant complications. As a first step toward developing a substitute treatment, we implanted engineered tissue constructs in rat hearts to create an alternative AV conduction pathway. We found that skeletal muscle-derived cells in the constructs exhibited sustained electrical coupling through persistent expression and function of gap junction proteins. Using fluorescence in situ hybridization and polymerase chain reaction analyses, myogenic cells in the constructs were shown to survive in the AV groove of implanted hearts for the duration of the animal's natural life. Perfusion of hearts with fluorescently labeled lec-tin demonstrated that implanted tissues became vascularized and immunostaining verified the presence of proteins important in electromechanical integration of myogenic cells with surrounding re-cipient rat cardiomyocytes. Finally, using optical mapping and electrophysiological analyses, we provide evidence of permanent AV conduction through the implant in one-third of recipient animals. Our experiments provide a proof-of-principle that engineered tissue constructs can function as an electrical conduit and, ultimately, may offer a substitute treatment to conventional pacing therapy.