Proven in vivo efficacy is a key requirement for novel gene therapies proceeding to clinical trial. No gene therapies for corneal dystrophies have been able to progress into patient-led studies due to a lack of suitable animal models expressing a disease phenotype comparable to that which develops in humans. Herein, we show an allele-specific siRNA targeting the L132P KRT12 mutation, causative of a severe form of Meesmann Epithelial Corneal Dystrophy (MECD), when complexed with silicon-stabilized hybrid lipid nanoparticles (sshLNP), and applied topically twice daily for seven days, results in restoration of corneal thickness in a humanized mouse model (Krt12+/hL132P) for MECD. Furthermore, expression of disease biomarkers elevated in the MECD mouse model and verified in corneal epithelial cells of MECD family members, was reduced to that observed in unaffected wild-type (Krt12+/+) mice. This represents the first successful use of topical mutant allele-specific siRNA in the treatment of an autosomal genetic corneal dystrophy. The successful silencing of disease biomarkers after topical siRNA treatment indicates expected clinical benefit. Furthermore, we demonstrated that siRNA-sshLNPs can be successfully formulated in sodium hyaluronate-containing eye-drops without impairing efficacy of the siRNA.
In recent years, success has been achieved in treating several eye conditions with oligonucleotide-based therapies. Herein, we outline the experimentation involved in progressing selection and development of a lead therapeutic siRNA for R124H mutation of TGFBI gene which causes Granular Corneal Dystrophy Type 2 (GCD2/Avellino CD). Firstly, a series of siRNA designs, generated by a gene walk across the R124H TGFBI mutation site, were tested and a lead siRNA identified. The lead siRNA was delivered into an immortalised human corneal epithelial cell line to assess on-target efficacy and off-target effects. The in vivo efficacy of the lead R124H TGFBI siRNA, complexed with Bio-Courier technology, silicon stabilized hybrid lipid nanoparticles (sshLNP), was assessed in a mouse model of GCD2 which expressed the human R124H TGFBI transgene. Following topical siRNA application for 5 consecutive days, expression of the R124H mutant TGFBI transgene was measured and shown to be reduced by 22.4 % (± 15.7 %, p < 0.05). We investigated gene expression in the mouse cornea and showed expression of murine Tgfbi was 20-fold lower than TGFBI in human cornea, and expression of the mutant TGFBI transgene was a further 3-fold lower. This estimated 60-fold lower mutant transgene expression may explain the low frequency of corneal deposits observed in this mouse model, limiting its usefulness to test whether siRNA silencing is capable of phenotypic improvement or regression of GCD2/Avellino corneal dystrophy. We assessed WT TGFBI silencing in human primary corneal epithelial cells (PCEC) derived from human corneal limbal biopsy material, which express TGFBI at a similar level to human corneal biopsy. We demonstrated that a single 100 nM siRNA treatment, delivered by the sshLNP to the primary human corneal epithelial cells, gave 26.6 % (± 6.6 %, p < 0.001) reduction in TGFBI mRNA and a 15.4 % (±10.5 %, p < 0.05 %) reduction in TGFBi protein after 48 h. In consideration of the mutant gene expression levels in existing models of GCD2 disease, an ex vivo model of mutation-expressing primary corneal epithelial cells generated from corneal limbal biopsies from GCD2 patients would be more suitable than existing transgenic mouse models for future pre-clinical work in the development of gene silencing therapies for corneal dystrophies.
Cardiovascular disease remains a leading cause of death worldwide despite the use of available cardiovascular disease risk prediction tools. Identification of high-risk individuals via risk stratification and screening at sub-clinical stages, which may be offered by ocular screening, is important to prevent major adverse cardiac events. Retinal microvasculature has been widely researched for potential application in both diabetes and cardiovascular disease risk prediction. However, the conjunctival microvasculature as a tool for cardiovascular disease risk prediction remains largely unexplored. The purpose of this review is to evaluate the current cardiovascular risk assessment methods, identifying gaps in the literature that imaging of the ocular microcirculation may have the potential to fill. This review also explores the themes of machine learning, risk scores, biomarkers, medical imaging, and clinical risk factors. Cardiovascular risk classification varies based on the population assessed, the risk factors included, and the assessment methods. A more tailored, standardised and feasible approach to cardiovascular risk prediction that utilises technological and medical imaging advances, which may be offered by ocular imaging, is required to support cardiovascular disease prevention strategies and clinical guidelines.
Objective: Coronary microvascular dysfunction (CMD) is a cause of ischaemia with non-obstructive coronary arteries (INOCA). It is notoriously underdiagnosed due to the need for invasive microvascular function testing. We hypothesized that systemic microvascular dysfunction could be demonstrated non-invasively in the micro -circulation of the bulbar conjunctiva in patients with CMD. Methods: Patients undergoing coronary angiography for the investigation of chest pain or dyspnoea, with physiologically insignificant epicardial disease (fractional flow reserve >= 0.80) were recruited. All patients un-derwent invasive coronary microvascular function testing. We compared a cohort of patients with evidence of CMD (IMR >= 25 or CFR <2.0); to a group of controls (IMR <25 and CFR >= 2.0). Conjunctival imaging was performed using a previously validated combination of a smartphone and slit-lamp biomicroscope. This tech-nique allows measurement of vessel diameter and other indices of microvascular function by tracking erythrocyte motion. Results: A total of 111 patients were included (43 CMD and 68 controls). There were no differences in baseline demographics, co-morbidities or epicardial coronary disease severity. The mean number of vessel segments analysed per patient was 21.0 +/- 12.8 (3.2 +/- 3.5 arterioles and 14.8 +/- 10.8 venules). In the CMD cohort, sig-nificant reductions were observed in axial/cross-sectional velocity, blood flow, wall shear rate and stress. Conclusion: The changes in microvascular function linked to CMD can be observed non-invasively in the bulbar conjunctiva. Conjunctival vascular imaging may have utility as a non-invasive tool to both diagnose CMD and augment conventional cardiovascular risk assessment.
BACKGROUND:Atherosclerotic heart disease often remains asymptomatic until presentation with a major adverse cardiovascular event. Primary preventive therapies improve outcomes, but conventional screening often misattributes risk. Vascular imaging can be utilised to detect atherosclerosis, but often involves ionising radiation. The conjunctiva is a readily accessible vascular network allowing non-invasive hemodynamic evaluation. AIM:To compare conjunctival microcirculatory function in patients with and without obstructive coronary artery disease. METHODS:We compared the conjunctival microcirculation of myocardial infarction patients (MI-cohort) to controls with no obstructive coronary artery disease (NO-CAD cohort). Conjunctival imaging was performed using a smartphone and slit-lamp biomicroscope combination. Microvascular indices of axial (Va) and cross-sectional (Vcs) velocity; blood flow rate (Q); and wall shear rate (WSR) were compared in all conjunctival vessels between 5 and 45 μm in diameter. RESULTS:A total of 127 patients were recruited (66 MI vs 61 NO-CAD) and 3602 conjunctival vessels analysed (2414 MI vs 1188 NO-CAD). Mean Va, Vcs and Q were significantly lower in the MI vs NO-CAD cohort (Va 0.50 ± 0.17 mm/s vs 0.55 ± 0.15 mm/s, p < 0.001; Vcs 0.35 ± 0.12 mm/s vs 0.38 ± 0.10 mm/s, p < 0.001; Q 154 ± 116 pl/s vs 198 ± 130 pl/s, p < 0.001). To correct for differences in mean vessel diameter, WSR was compared in 10-36 μm vessels (3268/3602 vessels) and was lower in the MI-cohort (134 ± 64 s-1 vs 140 ± 63 s-1, p = 0.002). CONCLUSIONS:Conjunctival microcirculatory alterations can be observed in patients with obstructive coronary artery disease. The conjunctival microvasculature merits further evaluation in cardiovascular risk screening.
Familial hypocalciuric hypercalcemia type 2 (FHH2) and autosomal dominant hypocalcemia type 2 (ADH2) are due to loss- and gain-of-function mutations, respectively, of the GNA11 gene that encodes the G protein subunit Gα11, a signaling partner of the calcium-sensing receptor (CaSR). To date, four probands with FHH2-associated Gα11 mutations and eight probands with ADH2-associated Gα11 mutations have been reported. In a 10-year period, we identified 37 different germline GNA11 variants in >1200 probands referred for investigation of genetic causes for hypercalcemia or hypocalcemia, comprising 14 synonymous, 12 noncoding, and 11 nonsynonymous variants. The synonymous and noncoding variants were predicted to be benign or likely benign by in silico analysis, with 5 and 3, respectively, occurring in both hypercalcemic and hypocalcemic individuals. Nine of the nonsynonymous variants (Thr54Met, Arg60His, Arg60Leu, Gly66Ser, Arg149His, Arg181Gln, Phe220Ser, Val340Met, Phe341Leu) identified in 13 probands have been reported to be FHH2- or ADH2-causing. Of the remaining nonsynonymous variants, Ala65Thr was predicted to be benign, and Met87Val, identified in a hypercalcemic individual, was predicted to be of uncertain significance. Three-dimensional homology modeling of the Val87 variant suggested it was likely benign, and expression of Val87 variant and wild-type Met87 Gα11 in CaSR-expressing HEK293 cells revealed no differences in intracellular calcium responses to alterations in extracellular calcium concentrations, consistent with Val87 being a benign polymorphism. Two noncoding region variants, a 40bp-5'UTR deletion and a 15bp-intronic deletion, identified only in hypercalcemic individuals, were associated with decreased luciferase expression in vitro but no alterations in GNA11 mRNA or Gα11 protein levels in cells from the patient and no abnormality in splicing of the GNA11 mRNA, respectively, confirming them to be benign polymorphisms. Thus, this study identified likely disease-causing GNA11 variants in <1% of probands with hypercalcemia or hypocalcemia and highlights the occurrence of GNA11 rare variants that are benign polymorphisms. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
This chapter discusses the current status of therapeutic gene therapy strategies for the cornea. The cornea offers the ideal candidate for targeted gene therapy due to its small surface area, accessibility, ease of visualization, and its unique immune-privileged status. Corneal dystrophies are a group of inherited, largely monogenic, heterogeneous, bilateral disorders that affect the transparency or shape of the cornea. Clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 gene editing offers the opportunity to treat these disorders even before symptoms appear. Maximizing on-target cleavage while minimizing off-target cleavage is a major concern for the therapeutic use of CRISPR/Cas9, thus current efforts in the gene editing field are focused on optimizing these two parameters. In addition, delivery of CRISPR/Cas9 components to the cornea is a challenge, various viral and nonviral platforms are being explored to develop a vehicle that is highly efficient, specific, and nontoxic.
•IgG anti-SARS-CoV-2 Omicron spike glycoprotein antibodies were detected in 100% of health care workers, a real world population attending general practice for vaccination and haemodialysis patients 4 weeks after a third SARS-CoV-2 vaccine dose (Pfizer-BioNtech 162b2).•Against both Delta and Omicron variants, antibody levels were higher in the cohort who had previously received two doses of Astrazeneca ChAdOx1 nCoV-19 vaccine than two doses of Pfizer-Biontech 162b2.•Prior to this third vaccine dose and 6 months post second vaccine dose, there was evidence of significant waning of antibody reactivity against Delta and Omicron variants of concern, particularly in individuals initially receiving two doses of Astrazeneca ChAdOx1 nCoV-19.
The urgent need to scale up testing capacity during the COVID-19 pandemic has prompted the rapid development of point-of-care diagnostic tools such as lateral flow immunoassays (LFIA) for large-scale community-based rapid testing. However, studies of how the general public perform when using LFIA tests in different environmental settings are scarce. This user experience (UX) study of 264 participants in Northern Ireland aimed to gather a better understanding of how self-administered LFIA tests were performed by the general public at home. The UX performance was assessed via analysis of a post-test questionnaire including 30 polar questions and 11 7-point Likert scale questions, which covers the multidimensional aspects of UX in terms of ease of use, effectiveness, efficiency, accuracy and satisfaction. Results show that 96.6% of participants completed the test with an overall average UX score of 95.27% [95% confidence interval (CI) 92.71–97.83%], which suggests a good degree of user experience and effectiveness. Efficiency was assessed based on the use of physical resources and human support received, together with the mental effort of self-administering the test measured via NASA Task Load Index (TLX). The results for six TLX subscales show that the participants scored the test highest for mental demand and lowest for physical demand, but the average TLX score suggests that the general public have a relatively low level of mental workload when using LFIA self-testing at home. Five printed LFIA testing results (i.e. the ‘simulated’ results) were used as the ground truth to assess the participant’s performance in interpreting the test results. The overall agreement (accuracy) was 80.63% [95% CI 75.21–86.05%] with a Kappa score 0.67 [95% CI 0.58–0.75] indicating substantial agreement. The users scored lower in confidence when interpreting test results that were weak positive cases (due to the relatively low signal intensity in the test-line) compared to strong positive cases. The end-users also found that the kit was easier to use than they expected (p < 0.001) and 231 of 264 (87.5%) reported that the test kit would meet their requirements if they needed an antibody testing kit. The overall findings provide an insight into the opportunities for improving the design of self-administered SARS-CoV-2 antibody testing kits for the general public and to inform protocols for future UX studies of LFIA rapid test kits.
Introduction: The AbC-19™ lateral flow immunoassay (LFIA) performance was evaluated on plasma samples from a SARS-CoV-2 vaccination cohort, WHO international standards for anti-SARS-CoV-2 IgG (human), individuals ≥2 weeks from infection of RT-PCR confirmed SARS-CoV-2 genetic variants, as well as microorganism serology.Methods: Pre-vaccination to three weeks post-booster samples were collected from a cohort of 111 patients (including clinically extremely vulnerable patients) from Northern Ireland. All patients received Oxford-AstraZeneca COVID-19 vaccination for the first and second dose, and Pfizer-BioNTech for the third (first booster). WHO international standards, 15 samples from 2 variants of concern (Delta and Omicron) and cross-reactivity with plasma samples from other microorganism infections were also assessed on AbC-19™.Results: All 80 (100%) participants sampled post-booster had high positive IgG responses, compared to 38/95 (40%) participants at 6 months post-first vaccination. WHO standard results correlated with information from corresponding biological data sheets, and antibodies to all genetic variants were detected by LFIA. No cross-reactivity was found with exception of one (of five) Dengue virus samples.Conclusion: These findings suggest BNT162b2 booster vaccination enhanced humoral immunity to SARS-CoV-2 from pre-booster levels, and that this antibody response was detectable by the LFIA. In combination with cross-reactivity, standards and genetic variant results would suggest LFIA may be a cost-effective measure to assess SARS-CoV-2 antibody status.
Background: Aortic stenosis (AS) is associated with pathophysiological changes in both left ventricular and coronary microvascular structure and function. The treatment of AS with transcatheter aortic valve replacement (TAVR) has been associated with improvements in invasive indices of coronary microvascular function. This study sought to address whether systemic microvascular dysfunction was present in patients with AS and if microvascular function was altered by treatment of aortic stenosis with TAVR. The conjunctival microcirculation was used as the site for the non-invasive assessment of systemic microvascular function. Methods: Patients undergoing TAVR for the treatment of severe AS were compared to a cohort of age- and sex-matched controls without valvular heart disease. Conjunctival vascular imaging was performed in all subjects using a previously validated combination of a smartphone and slit-lamp biomicroscope. This technique allowed measurement of vessel diameter and other indices of microvascular function by tracking erythrocyte motion. Conjunctival hemodynamics were compared pre- and post-TAVR, in addition to between the severe AS and control cohorts. Results: A total of 165 patients were included (90 severe AS and 75 controls). Baseline characteristics were well matched between groups. In comparison to the control cohort, arteriole axial (Va) and cross-sectional velocity (Vcs) were significantly lower in females with AS (Va severe AS 0.53 ± 0.11mm/s vs control 0.59 ± 0.12mm/s, p=0.047; Vcs severe AS 0.38 ± 0.07mm/s vs control 0.41 ± 0.08mm/s, p=0.043), but not in males (Va severe AS 0.61 ± 0.11mm/s vs control 0.58 ± 0.10mm/s, p=0.19; Vcs severe AS 0.43 ± 0.08mm/s vs control 0.41 ± 0.07mm/s, p=0.20). Arteriole Va and Vcs significantly increased following TAVR in females (Va Pre-TAVR 0.52 ± 0.16mm/s vs post-TAVR 0.59 ± 0.15mm/s, p<0.001; Vcs Pre-TAVR 0.37 ± 0.11mm/s vs post-TAVR 0.42 ± 0.11mm/s, p<0.001). Conclusion: This study highlights sex-specific differences in conjunctival microvascular function in patients with severe AS. In this study TAVR resulted in significant improvements in conjunctival arteriolar V a and V cs . These findings are consistent with severe AS being a reversible cause of systemic microvascular dysfunction.
Abstract Background Ischaemia with normal coronary arteries (INOCA) may result in disabling symptoms and has an association with adverse long-term prognosis. The diagnosis of INOCA necessitates invasive coronary angiography to perform a physiological evaluation of microvascular function. The conjunctiva has a readily assessable microvascular network in which physiological parameters can be evaluated. We compared conjunctival haemodynamics in patients with and without coronary microvascular disease (MVD) to assess if systemic microvascular dysfunction was present in this coronary artery disease sub-group. Methods In this study, we recruited patients undergoing invasive coronary angiography for the investigation of angina or angina equivalent symptoms. All patients had physiologically insignificant epicardial disease (FFR≥0.80) and underwent a physiological evaluation of coronary microvascular function. We compared a group with evidence of coronary MVD (IMR≥25 or CFR<2.0); to a group of controls without MVD (IMR<25 and CFR≥2.0). The conjunctival microvasculature was imaged using a previously validated combination of a smartphone and slit-lamp biomicroscope. The conjunctival vasculature was assessed using a semi-automated process of vessel diameter measurement and erythrocyte tracking to obtain haemodynamic parameters of microvascular function. Results A total of 111 patients were included (43 MVD and 68 controls). There were no differences in baseline demographics, co-morbidities, epicardial coronary disease severity or regular pharmacological therapies between the groups. Mean coronary flow reserve (CFR) was lower and mean index of microcirculatory resistance (IMR) higher in the MVD cohort (CFR 2.5±1.3 vs 5.2±2.5, p<0.001 and IMR 28.4±11.8 vs 13.7±5.0, p<0.001). A total of 2295 conjunctival vessels were analysed. The mean number of vessels per patient was 21.0±12.8 (3.2±3.5 arterioles and 14.8±10.8 venules). Significant reductions in axial/cross-sectional velocity, wall shear rate and wall shear stress were observed in the MVD cohort. Table 1 demonstrates a comparison of conjunctival physiological parameters between the groups. The most marked differences were observed in conjunctival arterioles. Due to the heterogenous size distribution of microvessels, arterioles were categorised into 2 diameter sub-groups (10–25 μm and 25–40 μm) for analysis (Table 2). Conclusion The reductions in microvascular blood flow velocity and rate that form the basis for the diagnosis of coronary microvascular dysfunction can be observed non-invasively in the bulbar conjunctiva microcirculation. Conjunctival vascular imaging may have utility as a non-invasive imaging modality to both diagnose microvascular dysfunction and augment conventional cardiovascular risk stratification. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Belfast Trust Heart Trust Fund and Northern Ireland Chest Heart and Stroke
Variants of SARS-CoV-2 may evade natural and vaccine induced immunity and monoclonal antibody immunotherapeutics. There is an urgent need to know how well antibodies, induced by healthy and Clinically Extremely Vulnerable (CEV) patients, will bind and thus help reduce transmission and severity of infection from variants of concern (VOC). This study determines the cross-reactive binding of serum antibodies obtained prior to and 28 days after a third vaccination in three cohorts; a health care worker cohort who received three doses of Pfizer-BioNtech (PPP), a cohort of CEV patients received two doses of the AstraZeneca-ChAdOx1-nCoV-19 (AAP) vaccine, followed by a third PFZ vaccine and a haemodialysis cohort that had a mixture of two AZ or PFZ vaccines followed by a PFZ booster. Six months post second vaccine there was evidence of antibody waning with 58.9% of individuals in the HD cohort seropositive against Wuhan, 34.4% Delta and 62.2% Omicron strains. For the AAP cohort, equivalent figures were 62.5%, 45.8% and 91.7% and the PPP cohort 92.2%, 90% and 91.1%. Post third dose vaccination there were universal increases in seropositivity and median optical density. For the HD cohort, 98.8% were seropositive to the Wuhan strain, 97.6% against Delta and 100% against Omicron strains. For the PPP and AAP cohorts, 100% were seropositive against all 3 strains. Lastly, we examined the WHO NIBSC 20/136 standard and there was no loss of antibody binding to either VOC. Similarly, a dilution series of Sotrovimab (GSK) found this therapeutic monoclonal antibody bound similarly to all VOC.
BACKGROUND:This study evaluates spike protein IgG antibody response following Oxford-AstraZeneca COVID-19 vaccination using the AbC-19™ lateral flow device.METHODS:Plasma samples were collected from n = 111 individuals from Northern Ireland. The majority were >50 years old and/or clinically vulnerable. Samples were taken at five timepoints from pre-vaccination until 6-months post-first dose.RESULTS:20.3% of participants had detectable IgG responses pre-vaccination, indicating prior COVID-19. Antibodies were detected in 86.9% of participants three weeks after the first vaccine dose, falling to 74.7% immediately prior to the second dose, and rising to 99% three weeks post-second vaccine. At 6-months post-first dose, this decreased to 90.5%. At all timepoints, previously infected participants had significantly higher antibody levels than those not previously infected.CONCLUSION:This study demonstrates that strong anti-spike protein antibody responses are evoked in almost all individuals that receive two doses of Oxford-AstraZeneca vaccine, and which largely persist beyond six months after first vaccination.
Microvascular haemodynamic alterations are associated with coronary artery disease (CAD). The conjunctival microcirculation can easily be assessed non-invasively. However, the microcirculation of the conjunctiva has not been previously explored in clinical algorithms aimed at identifying patients with CAD. This case-control study involved 66 patients with post-myocardial infarction and 66 gender-matched healthy controls. Haemodynamic properties of the conjunctival microcirculation were assessed with a validated iPhone and slit lamp-based imaging tool. Haemodynamic properties were extracted with semi-automated software and compared between groups. Biomarkers implicated in the development of CAD were assessed in combination with conjunctival microcirculatory parameters. The conjunctival blood vessel parameters and biomarkers were used to derive an algorithm to aid in the screening of patients for CAD. Conjunctival blood velocity measured in combination with the blood biomarkers (N-terminal pro-brain natriuretic peptide and adiponectin) had an area under receiver operator characteristic curve (AUROC) of 0.967, sensitivity 93.0%, specificity 91.5% for CAD. This study demonstrated that the novel algorithm which included a combination of conjunctival blood vessel haemodynamic properties, and blood-based biomarkers could be used as a potential screening tool for CAD and should be validated for potential utility in asymptomatic individuals.
Purpose: To evaluate the therapeutic benefit of a novel peptide, ALM201, in ocular pathologic vascularization.Design: Experimental study in mouse, rat, and rabbit animal models. Participants: Ten-week-old Lister Hooded male rats, 8-week-old Brown Norway male rats, 9-day-old C57BL/6J mice, and 12-month-old New Zealand male rabbits.Methods: Corneal vascularization was scored for vessel density and vessel distance to suture in a rat corneal suture model. Ocular penetration and biodistribution were evaluated by matrix-assisted laser desorption/ioni-zation mass spectrometry imaging after topical ALM201 application to rabbit eyes. A mouse choroidal sprouting assay, with aflibercept as positive control, was used to evaluate choroidal neovascularization (CNV) in the posterior segment tissue. Efficacy of topical ALM201 was assessed using a rat laser CNV model of neovascular age-related macular degeneration.Main Outcome Measures: Clinical scoring and histologic analysis of vascularized corneas, sprouting area, lesion size, and vessel leakiness in posterior segments.Results: Assessment of ALM201 treatment in the rat corneal suture model showed a significant decrease in vessel density (P = 0.0065) and vessel distance to suture (P = 0.021) compared with vehicle control (phosphate -buffered saline [PBS]). Infiltration of inflammatory cells into the corneal stroma also was reduced significantly compared with PBS (724.5 & PLUSMN; 122 cells/mm2 vs. 1837 & PLUSMN; 195.9 cells/mm2, respectively; P = 0.0029). Bio-distribution in rabbit eyes confirmed ALM201 bioavailability in anterior and posterior ocular segments 1 hour after topical instillation. ALM201 treatment significantly suppressed choroid vessel sprouting when compared with PBS treatment (44.5 & PLUSMN; 14.31 pixels vs. 120.9 & PLUSMN; 33.37 pixels, respectively; P = 0.04) and was not inferior to aflibercept (65.63 & PLUSMN; 11.86 pixels; P = 0.7459). Furthermore, topical ALM201 significantly improved vessel leakiness (leakage scores: 2.1 & PLUSMN; 0.7 vs. 2.9 & PLUSMN; 0.1; P = 0.0274) and lesion size (144,729 & PLUSMN; 33,239 mm3 vs. 187,923 & PLUSMN; 28,575 mm3; P = 0.03) in the rat laser CNV model when compared with topical PBS vehicle.Conclusions: ALM201 is a promising novel molecule with anti-inflammatory and antivascularization activity and is a strong candidate to meet the clinical need of a new, topically delivered therapeutic agent for treating inflammation and pathologic vascularization in the anterior and posterior segments of the eye. Ophthalmology Science 2022;2:100150 & COPY; 2022 by the American Academy of Ophthalmology. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Microcirculatory dysfunction occurs early in cardiovascular disease (CVD) development. Acute myocardial infarction (MI) is a late consequence of CVD. The conjunctival microcirculation is readily-accessible for quantitative assessment and has not previously been studied in MI patients. We compared the conjunctival microcirculation of acute MI patients and age/sex-matched healthy controls to determine if there were differences in microcirculatory parameters. We acquired images using an iPhone 6s and slit-lamp biomicroscope. Parameters measured included diameter, axial velocity, wall shear rate and blood volume flow. Results are for all vessels as they were not sub-classified into arterioles or venules. The conjunctival microcirculation was assessed in 56 controls and 59 inpatients with a presenting diagnosis of MI. Mean vessel diameter for the controls was 21.41 ± 7.57 μm compared to 22.32 ± 7.66 μm for the MI patients (p < 0.001). Axial velocity for the controls was 0.53 ± 0.15 mm/s compared to 0.49 ± 0.17 mm/s for the MI patients (p < 0.001). Wall shear rate was higher for controls than MI patients (162 ± 93 s −1 vs 145 ± 88 s −1 , p < 0.001). Blood volume flow did not differ significantly for the controls and MI patients (153 ± 124 pl/s vs 154 ± 125 pl/s, p = 0.84). This pilot iPhone and slit-lamp assessment of the conjunctival microcirculation found lower axial velocity and wall shear rate in patients with acute MI. Further study is required to correlate these findings further and assess long-term outcomes in this patient group with a severe CVD phenotype.
Lateral flow immunoassays are low cost, rapid and highly efficacious point-of-care devices, which have been used for SARS-CoV-2 antibody testing by professionals. However, there is a lack of understanding about how self-administered tests are used by the general public for mass testing in different environmental settings. The purpose of this study was to assess the user experience (UX) (including usability) of a self-testing kit to identify COVID-19 antibodies used by a representative sample of the public in their cars, which included 1544 participants in Northern Ireland. The results based on 5-point Likert ratings from a post-test questionnaire achieved an average UX score of 96.03% [95% confidence interval (CI) 95.05–97.01%], suggesting a good degree of user experience. The results of the Wilcoxon rank sum tests suggest that UX scores were independent of the user’s age and education level although the confidence in this conclusion could be strengthened by including more participants aged younger than 18 and those with only primary or secondary education. The agreement between the test result as interpreted by the participant and the researcher was 95.85% [95% CI 94.85–96.85%], Kappa score 0.75 [95% CI 0.69–0.81] (indicating substantial agreement). Text analysis via the latent Dirichlet allocation model for the free text responses in the survey suggest that the user experience could be improved for blood-sample collection, by modifying the method of sample transfer to the test device and giving clearer instructions on how to interpret the test results. The overall findings provide an insight into the opportunities for improving the design of SARS-CoV-2 antibody testing kits to be used by the general public and therefore inform protocols for future user experience studies of point-of-care tests.
Purpose: Congenital heart disease (CHD) is the most common live birth defect and a proportion of these patients have chronic hypoxia. Chronic hypoxia leads to secondary erythrocytosis resulting in microvascular dysfunction and increased thrombosis risk. The conjunctival microcirculation is easily accessible for imaging and quantitative assessment. It has not previously been studied in adult CHD patients with cyanosis (CCHD). Methods: We assessed the conjunctival microcirculation and compared CCHD patients and matched healthy controls to determine if there were differences in measured microcirculatory parameters. We acquired images using an iPhone 6s and slit-lamp biomicroscope. Parameters measured included diameter, axial velocity, wall shear rate and blood volume flow. The axial velocity was estimated by applying the 1D + T continuous wavelet transform (CWT). Results are for all vessels as they were not sub-classified into arterioles or venules. Results: 11 CCHD patients and 14 healthy controls were recruited to the study. CCHD patients were markedly more hypoxic compared to the healthy controls (84% vs 98%, p = 0.001). A total of 736 vessels (292 vs 444) were suitable for analysis. Mean microvessel diameter (D) did not significantly differ between the CCHD patients and controls (20.4 +/- 2.7 mu m vs 20.2 +/- 2.6 mu m, p = 0.86). Axial velocity (Va) was lower in the CCHD patients (0.47 +/- 0.06 mm/s vs 0.53 +/- 0.05 mm/s, p = 0.03). Blood volume flow (Q) was lower for CCHD patients (121 +/- 30pl/s vs 145 +/- 50pl/s, p = 0.65) with the greatest differences observed in vessels >22 mu m diameter (216 +/- 121pl/s vs 258 +/- 154pl/s, p = 0.001). Wall shear rate (WSR) was significantly lower for the CCHD group (153 +/- 27 s(-1)vs 174 +/- 22s(-1), p = 0.04). Conclusions: This iPhone and slit-lamp combination assessment of conjunctival vessels found lower axial velocity, wall shear rate and in the largest vessel group, lower blood volume flow in chronically hypoxic patients with congenital heart disease. With further study this assessment method may have utility in the evaluation of patients with chronic hypoxia.