Our novel findings suggest the possibility of targeting these CSCs by modulation of paracrine RAS signaling.
  Coronavirus Disease 2019 (COVID19) has caused significant global morbidity and mortality, especially in persons with underlying cardiovascular disease. There have been concerns that lipid-lowering therapy (LLT) increases angiotensin-converting enzyme 2 levels. Conversely, pleiotropic effects of statins can theoretically protect against severe COVID19 infection, supporting evidence from other respiratory illnesses in which statin use probably confers benefit.
 
  There is an abundance of studies that show that statins are safe and potentially protect against severe COVID19 infection (critical illness and death), even when adjustment for potential confounders is undertaken. However, the evidence is limited to retrospective cohorts. The benefit for patients with diabetes is less clear. There is a paucity of evidence for other LLT agents. Available clinical guidelines recommend the ongoing use of LLT in patients with COVID19 (unless specifically contra-indicated) and the data from available studies support these.
 
  In patients with COVID19 infection, LLT should be continued. However, the current findings need substantiating in larger prospective clinical studies with specific examination of the possible mechanisms by which LLT confers benefit from COVID19.
 In patients with COVID19 infection, LLT should be continued. However, the current findings need substantiating in larger prospective clinical studies with specific examination of the possible mechanisms by which LLT confers benefit from COVID19.
  Morphine-standardized doses are used in clinical practice and research to account for molecular potency. Ninety milligrams of morphine equivalents (MME) per day are considered a "high dose" risk threshold in guidelines, laws, and by payers. Although ubiquitously cited, the "CDC definition" of daily MME lacks a clearly defined denominator. Our objective was to assess denominator-dependency on "high dose" classification across competing definitions.
 
  To identify definitional variants, we reviewed literature and electronic prescribing tools, yielding 4 unique definitions. Using Prescription Drug Monitoring Programs data (July to September 2018), we conducted a population-based cohort study of 3,916,461 patients receiving outpatient opioid analgesics in California (CA) and Florida (FL). The binary outcome was whether patients were deemed "high dose" (>90 MME/d) compared across 4 definitions. We calculated I2 for heterogeneity attributable to the definition.
 
  Among 9,436,640 prescriptions, 42% overlapped, w to definitional variation.
  To describe the histopathological characteristics of limbal stem cell deficiency (LSCD) due to chronic vernal keratoconjunctivitis (VKC).
 
  This retrospective study included 14 eyes of 13 patients who underwent simple limbal epithelial transplantation for total LSCD from 2017 to 2018. The histological characteristics of the excised fibrovascular pannus were compared between 2 groups of 7 eyes, each with LSCD due to VKC and chemical burns (CB). Histological characteristics and type of inflammation were studied using special stains and immunohistochemistry. Fisher exact test was used to detect the statistical significance of the histological differences between both groups.
 
  Epithelial hypertrophy, epithelial downgrowth, and eosinophilic infiltration were noted in all eyes in the VKC group (7/7, 100%). Epithelial hypertrophy was noted in 3 of the 7 (42.8%) eyes in the CB group, whereas epithelial downgrowth and eosinophilic infiltrates were absent. The average chronic inflammatory score of the pannus (5.28) idate the reasons behind these unique findings.
  Corneal neovascularization is an important risk factor for graft rejection after keratoplasty, although its role in posterior lamellar keratoplasty is not yet well defined. The aim of this work was to describe clinically available approaches that target corneal neovascularization preoperatively to improve graft survival after subsequent penetrating keratoplasty (PK) and to present findings on Descemet membrane endothelial keratoplasty (DMEK) in eyes with neovascularization.
 
  Recent work on the use of anti-vascular endothelial growth factor agents, fine needle diathermy (FND), and corneal collagen crosslinking (CXL) to regress corneal neovascularization before PK is summarized. Furthermore, studies that have investigated the outcome of DMEK in vascularized eyes are presented.
 
  Pretreatment of recipient corneas with FND combined with anti-vascular endothelial growth factor agents is an effective method to reduce long-standing corneal neovascularization and results in relatively low rejection rates after subthe precise role of preexisting corneal neovascularization in high-risk DMEK.
  The purpose of this article is to report 3 cases of corneal allograft rejection that occurred in temporal proximity to administration of the zoster subunit vaccine (RZV).
 
  Three cases of corneal transplant rejection that developed after RZV administration were identified. Clinical history, including existence of other risk factors, timing of rejection, corticosteroid therapy at the time of onset of rejection, and course were reviewed.
 
  The onset of symptoms occurred 5 weeks after the first RZV dose in 1 patient and 1 and 6 weeks after the second dose in the other 2 patients. Coexisting risk factors included history of endothelial keratoplasty in the fellow eye in 1 patient and previous failure of a penetrating keratoplasty because of rejection in a second patient. The third patient had a history of 1 episode of rejection in a previous graft that resolved and then experienced graft failure over several years. In 2 patients, rejection developed despite relatively high levels of topical steroid therapy prednisolone acetate 1%, 4 × per day in 1 patient and difluprednate 0.05%, 3 × per day in a second patient.
 
  RZV, which elicits a more robust immune reaction than the zoster live-attenuated vaccine, ZVL, may increase the risk of allograft rejection in immunocompetent patients with preexisting corneal endothelial or penetrating transplants. Based on the available data, it may be reasonable to increase the topical corticosteroid regimen before the first dose, until approximately 3 months after the second dose of ZVL.
 RZV, which elicits a more robust immune reaction than the zoster live-attenuated vaccine, ZVL, may increase the risk of allograft rejection in immunocompetent patients with preexisting corneal endothelial or penetrating transplants.  https://www.selleckchem.com/products/2-aminoethyl-diphenylborinate.html  Based on the available data, it may be reasonable to increase the topical corticosteroid regimen before the first dose, until approximately 3 months after the second dose of ZVL.