ABSTRACT
To unravel the source of SARS-CoV-2 introduction and the pattern of its spreading and evolution in the United Arab Emirates, we conducted meta-transcriptome sequencing of 1,067 nasopharyngeal swab samples collected between May 9th and Jun 29th, 2020 during the first peak of the local COVID-19 epidemic. We identified global clade distribution and eleven novel genetic variants that were almost absent in the rest of the world defined five subclades specific to the UAE viral population. Cross-settlement human-to-human transmission was related to the local business activity. Perhaps surprisingly, at least 5% of the population were co-infected by SARS-CoV-2 of multiple clades within the same host. We also discovered an enrichment of cytosine-to-uracil mutation among the viral population collected from the nasopharynx, that is different from the adenosine-to-inosine change previously reported in the bronchoalveolar lavage fluid samples and a previously unidentified upregulation of APOBEC4 expression in nasopharynx among infected patients, indicating the innate immune host response mediated by ADAR and APOBEC gene families could be tissue-specific. The genomic epidemiological and molecular biological knowledge reported here provides new insights for the SARS-CoV-2 evolution and transmission and points out future direction on host-pathogen interaction investigation.
ABSTRACT
PURPOSE: To analyse the efficacy and outcome predictors of ranibizumab using a spectral-domain optical coherence tomography (SD-OCT)-driven treat-and-extend regimen (TER) versus SD-OCT-driven pro re nata regimen (PRN) in patients with cystoid macular oedema (CME) due to branch or central retinal vein occlusion (BRVO, CRVO). METHODS: Retrospective, consecutive case series. Evaluation included best corrected visual acuity (BCVA), morphological parameters on SD-OCT, and treatment frequency. RESULTS: From baseline to months 12, 18, and 24, BCVA improved by 16.6 ± 13.1, 15.5 ± 14.4, and 16.6 ± 15.8 letters, respectively, in TER (n = 45), compared to 11.3 ± 17.0, 11.0 ± 15.0, and 10 ± 20.5 letters in PRN (n = 31) (p = 0.152, p = 0.237, p = 0.172). The mean reduction in central retinal thickness was -261 ± 189, -272 ± 188, and -264 ± 158 µm, respectively, in TER, compared to -130 ± 196, -140 ± 210, and -166 ± 207 µm in PRN (p = 0.006, p = 0.017, p = 0.064). 59% (53%) of TER and 22% (17%) of PRN patients showed no intra- or subretinal fluid on SD-OCT at 12 (24) months. Using TER, the maximum recurrence-free treatment interval increased from 8.9 ± 2.3 weeks at 12 months to 9.8 ± 2.3 and 10.5 ± 2.7 weeks at 18 and 24 months, respectively. The number of injections was significantly higher in the TER than in the PRN group. CONCLUSIONS: In CME, due to BRVO/CRVO, TER provides better morphological outcome using more injections than PRN.
