Ectropion. / Ektropion.

In ectropion, the eyelid margin - typically the lower eyelid - is turned outward. This condition is becoming increasingly common due to the ageing population. Ectropion is classified as either acquired or congenital, with the former being the most prevalent. Acquired ectropion is further divided into involutional, paralytic, mechanical and cicatricial subtypes. Involutional ectropion is the most common where there is no patient population bias. This clinical review provides an overview of ectropion.

Suture materials. / Suturmaterialer.

Suture materials are of crucial importance for most surgical procedures, and knowledge about these is useful for all doctors. This clinical review article gives an introduction to the most common suture materials and their properties. Lastly, recent trends in suture technology are presented.

Skin grafting. / Hudtransplantasjon.

Skin grafting involves covering an area of missing skin with healthy skin tissue harvested from another part of the body. The aim of this clinical overview is to give a short introduction to the procedure.

Sericin-Induced Melanogenesis in Cultured Retinal Pigment Epithelial Cells Is Associated with Elevated Levels of Hydrogen Peroxide and Inflammatory Proteins.

We previously demonstrated that the silk protein sericin promotes pigmentation of retinal pigment epithelium (RPE) by activating the NF-κB pathway. Among numerous agents, NF-κB can be activated by hydrogen peroxide. In the present study, we explored possible associations between reactive oxygen species and sericin-induced melanogenesis in RPE. The proteome of human fetal RPE cultured for seven days with or without 1% sericin was analyzed using ingenuity pathway analysis (IPA). The proteomic data was verified by immunofluorescence and immunoblotting. Light microscopy and scanning electron microscopy were used to assess morphology. Dihydroethidium (DHE) and dihydrorhodamine (DHR) assays were used to measure superoxide and hydrogen peroxide species. Expression levels of proteins related to inflammation, differentiation, cell survival and cell adhesion were higher in cells cultured in Dulbecco's Modified Eagle Medium (DMEM) with 1% sericin, whereas cells cultured in DMEM alone showed higher expression levels of proteins associated with Bruch's membrane and cytoskeleton. Despite upregulation of inflammatory proteins, sericin co-cultured RPE yielded significantly higher cell viability compared to cells cultured without sericin. Addition of sericin to culture media significantly increased hydrogen peroxide-levels without significantly affecting superoxide-levels. We suggest that sericin-induced melanogenesis in cultured RPE is associated with elevated levels of superoxide dismutase, hydrogen peroxide and inflammatory proteins.

The Effects of Prolonged Storage on ARPE-19 Cells Stored at Three Different Storage Temperatures.

This study aimed to investigate how prolonged storage of adult retinal pigment epithelial (ARPE-19) cell sheets affects cell metabolism, morphology, viability, and phenotype. ARPE-19 cell sheets were stored at three temperatures (4 °C, 16 °C, and 37 °C) for three weeks. Metabolic status and morphology of the cells were monitored by sampling medium and examining cells by phase-contrast microscopy, respectively, throughout the storage period. Cell viability was analyzed by flow cytometry, and phenotype was determined by epifluorescence microscopy after the storage. Lactate production and glucose consumption increased heavily, while pH dropped considerably, through storage at 37 °C compared to 4 °C and 16 °C. During storage, morphology started to deteriorate first at 4 °C, then at 37 °C, and was maintained the longest at 16 °C. Viability of the cells after three weeks of storage was best preserved at 16 °C, while cells stored at 4 °C and 37 °C had reduced viability. Dedifferentiation indicated by reduced expression of retinal pigment epithelium-specific protein 65 (RPE65), zonula occludens protein 1 (ZO-1), and occludin after three weeks of storage was noticed in all experimental groups compared to control. We conclude that storage temperature affects the metabolic status of ARPE-19 cells and that 16 °C reduces metabolic activity while protecting viability and morphology.

Intense pulsed light treatment in meibomian gland dysfunction: Past, present, and future.

Dry eye disease is a highly prevalent condition, which can substantially impair quality of life, work productivity, and vision. It is considered an inflammatory disease and the most common cause is meibomian gland dysfunction. Despite many treatment alternatives being available, including artificial tears, warm compresses, antibiotics, and anti-inflammatory therapy, lasting treatment effects are rare. Over the last two decades, intense pulsed light therapy, after being well established in dermatology, has been gradually introduced to the field of ophthalmology to treat meibomian gland dysfunction. The purpose of the current article is to critically review the clinical studies assessing the use of intense pulsed light to treat meibomian gland dysfunction published to date. The vast majority of the included studies demonstrated improved symptoms and signs, although the degree of efficacy and its duration varied greatly depending on concomitant treatment, number of treatment sessions, and other factors. Several possible mechanisms of action concerning disease propagation and treatment efficacy are discussed. There is still a need for larger, randomised, longitudinal studies to define the most efficacious treatment regime and to predict which patients may benefit the most. More studies are needed on implementing biochemical analyses and machine learning algorithms. Such studies may prove beneficial in predicting treatment effects, defining optimal treatment regimens, and furthering our understanding of the mechanisms of action.

Corrigendum: Concise Review: Considering Optimal Temperature for Short-Term Storage of Epithelial Cells.

[This corrects the article DOI: 10.3389/fmed.2021.686774.].

Concise Review: Considering Optimal Temperature for Short-Term Storage of Epithelial Cells.

Transplantation of novel tissue-engineered products using cultured epithelial cells is gaining significant interest. While such treatments can readily be provided at centralized medical centers, delivery to patients at geographically remote locations requires the establishment of suitable storage protocols. One important aspect of storage technology is temperature. This paper reviews storage temperature for above-freezing point storage of human epithelial cells for regenerative medicine purposes. The literature search uncovered publications on epidermal cells, retinal pigment epithelial cells, conjunctival epithelial cells, corneal/limbal epithelial cells, oral keratinocytes, and seminiferous epithelial cells. The following general patterns were noted: (1) Several studies across different cell types inclined toward 4 and 16°C being suitable short-term storage temperatures. Correspondingly, almost all studies investigating 37°C concluded that this storage temperature was suboptimal. (2) Cell death typically escalates rapidly following 7-10 days of storage. (3) The importance of the type of storage medium and its composition was highlighted by some of the studies; however, the relative importance of storage medium vs. storage temperature has not been investigated systematically. Although a direct comparison between the included investigations is not reasonable due to differences in cell types, storage media, and storage duration, this review provides an overview, summarizing the work carried out on each cell type during the past two decades.

The Silk Protein Sericin Promotes Viability of ARPE-19 and Induced Pluripotent Stem Cell-Derived Retinal Pigment Epithelial Cells in vitro.

PURPOSE: Maintaining mature and viable retinal pigment epithelial cells (RPE) in vitro has proven challenging. Investigating compounds that can promote RPE-viability and maturation is motivated by RPE transplantation research, the quest to understand RPE physiology, and a desire to modulate RPE in pathological states. We have previously reported that the silk protein sericin promotes viability, maturation, and pigmentation of human fetal RPE. In the present study, our aim was to uncover whether these effects can be seen in adult retinal pigment epithelial cell line-19 (ARPE-19) and induced pluripotent stem cell-derived RPE (iPSC-RPE). METHODS: ARPE-19 and iPSC-RPE were cultured with or without 10 mg/mL sericin. After 7 days, viability was assessed with calcein-acetoxymethyl ester (CAM) and ethidium homodimer-1 (EH-1) assays, flow cytometry, and morphometric analysis. Expression levels of RPE65, tyrosinase, and Pmel17 were quantified to compare maturation between the sericin-treated and control cultures. Light microscopy and staining of the tight junction protein zonula occludens protein 1 (ZO-1) were employed to study sericin's effects on RPE morphology. We also measured culture medium pH, glucose, lactate, and extracellular ion content. RESULTS: Sericin-supplemented RPE cultures demonstrated significantly better viability compared to control cultures. Sericin appeared to improve ARPE-19 maturation and morphology in vitro. No effects were seen on RPE pigmentation with the concentration of sericin and duration of cell culture herein reported. CONCLUSIONS: This is the first study to demonstrate that supplementing the culture media with sericin promotes the viability of iPSC-RPE and ARPE-19. Sericin's viability-promoting effects may have important implications for retinal therapeutics and regenerative medicine research.