ABSTRACT
Although tropism of SARS-CoV-2 for respiratory tract epithelial cells is well established, an open question is whether the conjunctival epithelium is also a target for SARS-CoV-2. Conjunctival epithelial cells, which express viral entry receptors ACE2 and TMPRSS2, constitute the largest exposed epithelium of the ocular surface tissue, and may represent a relevant viral entry route. To address this question, we generated an organotypic air-liquid-interface model of conjunctival epithelium, composed of progenitor, basal and superficial epithelial cells and fibroblasts, which could be maintained successfully up to day 75 of differentiation. Using single-cell RNA Seq, with complementary imaging and virological assays, we observed that while all conjunctival cell types were permissive to SARS-CoV-2 genome expression, a productive infection did not ensue. The early innate immune response to SARS-CoV-2 infection in conjunctival cells was characterised by a robust autocrine and paracrine NF-K{beta} activity, without activation of antiviral interferon signalling. Collectively, these data enrich our understanding of SARS-CoV-2 infection at the human ocular surface, with potential implications for the design of preventive strategies and conjunctival transplants.
ABSTRACT
BACKGROUND: Because scientific data on the diet of diabetic Greek youngsters are scarce, diabetic experts use findings from international studies. However, because of diet variations between countries, this may result in problems in diabetes control. The aim of the present pilot study was to assess body composition, nutritional status, and diabetes control in Greek youngsters with type 1 diabetes mellitus (T1DM). METHODS: Twenty-four children and adolescents with diabetes, aged 4-16 years, and the same number of age- and sex-matched controls participated in the study. Anthropometry included stature, weight, and body fat determined by bioelectrical impedance analysis. Body mass index (BMI), fat mass index (FMI), fat-free mass index (FFMI), and z-scores were calculated. Diabetes control was evaluated through glycosylated hemoglobin (HbA1c) and dietary intake was recorded for 3 days. RESULTS: The FFMI, BMI z-score and weight-for-age z-score were lower in controls compared with diabetic youngsters (P ≤ 0.001, P ≤ 0.02, and P ≤ 0.01, respectively). Three diabetic participants were overweight (12.5%) and two controls were underweight (8.3%). The energy and nutrient intake was similar between the two groups, and all participants consumed a diet high in fats and proteins at the expense of carbohydrates. Dietary fat was highly correlated with BMI in both groups. The consumption of vitamin D was inadequate in the diabetic participants, but they had a higher intake of antioxidant vitamins, vitamin B(6) , and folate compared with the control group. CONCLUSIONS: In conclusion, youngsters with T1DM failed to adhere to the macronutrient recommendations for diabetes, but dietary patterns were similar in both the diabetic and control groups. The control of diabetes was not associated with any nutrient or anthropometric variable.
