Genome Sequences of SARS-CoV-2 Strains from the Republic of Moldova.

The whole-genome sequences of 15 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains from nasopharyngeal swab samples collected in the Republic of Moldova in June 2020 to September 2021 were determined. Little variability was observed in the early stages, when mostly clade 19A was circulating, followed by clade 20B. Later, multiple introductions of SARS-CoV-2 lineages B.1.1., B.1.1.7, and B.1.1.525 were detected. The B.1.1.7 lineage became predominant between December 2020 and June 2021, followed by the Delta variant.

Case report: Long-lasting SARS-CoV-2 infection with post-COVID-19 condition in two patients with chronic lymphocytic leukemia: The emerging therapeutic role of casirivimab/imdevimab.

Post-coronavirus disease 2019 (post-COVID-19) condition, previously referred to as long COVID, includes a post-acute syndrome defined by the presence of non-specific symptoms occurring usually 3 months from the onset of the acute phase and lasting at least 2 months. Patients with chronic lymphocytic leukemia (CLL) represent a high-risk population for COVID-19. Moreover, the response to SARS-CoV-2 vaccination is often absent or inadequate. The introduction of monoclonal antibodies (mAbs) in the treatment landscape of COVID-19 allowed to reduce hospitalization and mortality in mild-moderate SARS-CoV-2 infection, but limited data are available in hematological patients. We here report the effective use of casirivimab/imdevimab (CI) in the treatment of two CLL patients with persistent infection and post-COVID-19 condition. Full genome sequencing of viral RNA from nasopharyngeal swabs was performed at the time of COVID-19 diagnosis and before the administration of CI. Both patients experienced persistent SARS-CoV-2 infection with no seroconversion for 8 and 7 months, respectively, associated with COVID symptoms. In both cases after the infusion of CI, we observed a rapid negativization of the nasal swabs, the resolution of post-COVID-19 condition, and the development of both the IgG against the trimeric spike protein and the receptor-binding domain (RBD) of the spike protein. The analysis of the viral genome in the period elapsed from the time of COVID-19 diagnosis and the administration of mAbs showed the development of new mutations, especially in the S gene. The genome variations observed during the time suggest a role of persistent SARS-CoV-2 infection as a possible source for the development of viral variants. The effects observed in these two patients appeared strongly related to passive immunity conferred by CI treatment permitting SARS-CoV-2 clearance and resolution of post-COVID-19 condition. On these grounds, passive anti-SARS-CoV-2 antibody treatment may represent as a possible therapeutic option in some patients with persistent SARS-CoV-2 infection.

SARS-CoV-2 Genome Sequence Obtained from Ethiopia.

The coding-complete severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome sequences from 15 nasopharyngeal swabs collected in Addis Ababa, Ethiopia, during the period from December 2020 to March 2021 were determined using Illumina MiSeq technology. A sequence analysis identified that the B.1 SARS-CoV-2 lineage was most prevalent with the worrying emergence of B.1.1.7 in June 2021.

Whole-Genome Sequences of SARS-CoV-2 Isolates from the Dominican Republic.

Here, we report the genome sequences of five severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains that were obtained from symptomatic individuals with travel histories during community surveillance in the Dominican Republic in 2020. These sequences provide a starting point for further genomic studies of gene flow and molecular diversity in the Caribbean nation. Phylogenetic analysis suggests that all genomes correspond to the B.1 variant.

PERIPAPILLARY RETINAL NERVE FIBER THICKNESS CHANGES AFTER VITRECTOMY FOR EPIRETINAL MEMBRANE IN EYES WITH AND WITHOUT VITREOUS DETACHMENT.

PURPOSE: To compare the changes in postoperative peripapillary retinal nerve fiber layer (p-RNFL) thickness after vitrectomy for epiretinal membrane in eyes with preexisting posterior vitreous detachment (PVD) and eyes with surgically induced PVD. METHODS: This study included consecutive patients who underwent 25-gauge vitrectomy for epiretinal membrane. Eyes were divided, according to intraoperative PVD status, into a preexisting PVD group and surgically induced PVD group. Best-corrected visual acuity, p-RNFL thickness, and central retinal thickness were performed before and at 1, 3, and 6 months after surgery. RESULTS: One hundred and twenty eyes of 120 patients were enrolled: 64 eyes in the preexisting PVD group and 56 eyes in the surgically induced PVD group. In the preexisting PVD group at 6 months, the mean global p-RNFL thickness did not change, whereas it was reduced in the temporal sector (P = 0.034). In the surgically induced PVD group at 6 months, significant decreases were observed in global p-RNFL thickness (P = 0.027), temporal (P = 0.021), temporal inferior (P = 0.030), and nasal inferior sectors (P = 0.010). At 6 months, the two groups differed significantly in temporal (P < 0.001) and temporal inferior sectors (P = 0.004). The preoperative mean best-corrected visual acuity improved significantly at 6 months in both groups. CONCLUSION: Postoperative p-RNFL thickness after vitrectomy for epiretinal membrane tended to decrease in the temporal sector in all eyes and in the temporal inferior and nasal inferior sectors in eyes with surgically induced PVD.

STANDARD CUT RATE 25-GAUGE VITRECTOMY VERSUS ULTRAHIGH-SPEED 25-GAUGE SYSTEM IN CORE VITRECTOMY: A Randomized Clinical Trial.

PURPOSE: The aim of this study was to compare the efficiency and safety of ultrahigh-speed cut rate 25-gauge system and standard cut rate 25-gauge vitrectomy system. METHODS: In this single-center, prospective randomized study, all consecutive eyes that underwent 25-gauge vitrectomy at the Eye Clinic of the University of Ancona from September 2014 to November 2014 were randomized to receive 25-gauge vitrectomy with 7,500 cuts per minute (cpm) probes (7,500 Group) or 25-gauge vitrectomy with 5,000 cpm probes (Standard Group). Exclusion criteria were previously vitrectomized eye, trauma cases, retinal detachment with proliferative vitreoretinopathy, and endophthalmitis. Main outcome measure was core vitrectomy duration. Secondary outcome was the incidence of iatrogenic retinal breaks and other complications related to surgery. RESULTS: Overall, 62 eyes were enrolled; 31 eyes received 25-gauge 7,500 cpm vitrectomy and 31 eyes received 25-gauge 5,000 cpm vitrectomy. The duration of core vitrectomy was significantly lower in the 7,500 Group (P = 0.030, t-test for independent samples). Mean ± standard deviation core vitrectomy time was 161.32 ± 39.10 seconds in the 7,500 Group and 184.10 ± 41.69 seconds in the Standard Group. The observed difference in mean core vitrectomy duration between subjects treated with 7,500 cpm probes and those in the Standard Group was equal -22 seconds (95% confidence interval: -43.3 to -2.2). There was no difference in the incidence of iatrogenic breaks between the 2 groups, and there were no other complications over a 3-month follow-up period. CONCLUSION: The 25-gauge 7,500 cpm vitrectomy is an effective and safe surgical procedure, and it can significantly reduce core vitrectomy time in eyes undergoing vitreoretinal surgery.

Comparative study between amniotic-fluid mesenchymal stem cells and retinal pigmented epithelium (RPE) stem cells ability to differentiate towards RPE cells.

Dysfunction of the retinal pigmented epithelium (RPE) is one of the first effects of dry age-related macular degeneration (AMD) with consequent blindness. Hence, patients affected by this retinal disorder could benefit from a cell-based transplantation strategy for RPE. Actually, an effective protocol to approach this problem is lacking, though recently, it has been postulated the existence of a subpopulation of RPE stem cells (RPESCs) derived from adult RPE and able to reconstitute a functional RPE. On the other hand, the evidence related to the differentiative potential of human mesenchymal stem cells (MSCs) is continuously increasing. Among others, amniotic fluid-derived MSCs (AF-MSCs) may be a promising candidate, since these cells are characterized by high proliferation and differentiative potential. In this study, AF-MSCs and RPESCs were isolated, characterized to assay their stemness and induced to neuronal/retinal differentiation; specific RPE markers were then analyzed. Our results indicate that RPESCs are more suitable candidates for RPE replacement than AF-MSCs.