Evaluation of the retina, choroid and optic disc vascular structures in individuals with a history of COVID-19

INTRODUCTION

In this study, we aimed to detect changes in posterior segment structures and vascular density caused by COVID-19 using an optical coherence tomography angiography (OCTA) device.

MATERIALS AND METHODS

The study included 20 eyes of 20 patients no systemic or ocular disease who were followed at the Ophthalmology Clinic of Health Sciences University Antalya Training and Research Hospital. The OCTA images of these individuals taken prior to contracting COVID-19 and six months after recovery were examined.

RESULTS

The mean choriocapillaris blood flow was 2.00±0.13mm2 before COVID-19 and 2.08±0.23mm2 after the disease, and the mean subfoveal choroidal thickness was 247.33±7.65μm before the disease and 273.08±4.92μm after the disease, indicating a statistically significant difference (P=0.003, P=0.001, respectively). The mean retinal nerve fiber layer thickness before and after COVID-19 were 119.33±3.88 and 117.50±3.92μm, respectively, representing a statistically significant decrease (P<0.001).

CONCLUSION

This is the first study in the literature to evaluate the post-COVID-19 changes in the vascular structures of the eye compared to the pre-disease values. In this study, we found statistically significant changes in choriocapillaris blood flow, subfoveal chroidal thickness and retinal nerve fiber layer thickness after COVID-19 infection. Further research with a greater sample size is needed to explore the effect of COVID-19 on these parameters.

Anaerobic co-digestion of oil-extracted spent coffee grounds with various wastes: Experimental and kinetic modeling studies

The effect of oil extraction from spent coffee grounds as a pre-treatment strategy prior to anaerobic digestion besides assessing the feasibility of defatted spent coffee grounds co-digestion with spent tea waste, glycerin, and macroalgae were examined. Mesophilic BMP tests were performed using defatted spent coffee grounds alongside four co-substrates in the ratio of 25, 50, and 75%, respectively. The highest methane yield was obtained with the mono-digestion of defatted spent coffee grounds with 336 ± 7 mL CH₄/g VS and the yield increased with the increase in the mass ratio of defatted spent coffee grounds during co-digestion. Moreover, defatted spent coffee grounds showed the highest VS and TS removal at 35.5% and 32.1%, respectively and decreased thereafter. Finally, a linear regression model for the interaction effects between substrates was demonstrated and showed that distinctly mixing defatted spent coffee grounds, spent coffee grounds, and spent tea waste outperforms other triple mixed substrates.

Screening for the fragile X syndrome among mentally retarded males by hair root analysis

A noninvasive antibody test was used to identify male fragile X patients in special education schools, on the basis of the lack of FMRP in hair roots. We studied 300 males with mental retardation of unknown cause attending special schools. Patients were divided into two groups, based on the scores according to a fragile X check list (Group 1 </= 9 points and Group 2 >/= 10 points). Group 2 consists of 51 males and only 5 males in this group showed no FMRP expression in hair roots within the abnormal range (91%). Fragile X diagnosis in these cases was confirmed by DNA analysis. None of the males scoring more than 10 on the check list was diagnosed positive for the fragile X syndrome using DNA analysis. With our antibody test on hair roots we did not detect a fragile X patient in Group 1. The FMRP antibody test on hair roots is suitable in a screening program for the fragile X syndrome among mentally retarded males attending special education schools.

Epidemiological evaluation of the protection conferred by the Nivgrip vaccine against influenza caused by the A(H3N2) virus

The protection conferred by the inactivated influenza vaccine Nivgrip against influenza caused by the A(H3N2) virus was demonstrated in three school communities of a large urban centre during the epidemic outbreaks occurring in the winter season of 1983. The specific protection was reflected by the lower morbidity by influenza-like respiratory infections and by the absence or scarcity of postinfluenza complications in vaccinees.