Detection of Retinal Microvascular Changes with Optical Coherence Tomography Angiography in Patients with Acute Leukemia Without Retinopathy.

INTRODUCTION: Acute leukemia often affects microcirculation perfusion. This study aimed to investigate retinal microvascular changes in patients with acute leukemia without retinopathy during clinical remission using optical coherence tomography angiography (OCTA) and to determine the correlation of these changes with systemic laboratory values. METHODS: Thirty-eight patients in remission from acute leukemia with no retinopathy (NLR group) and 36 age-matched healthy individuals (control group) were included in this cross-sectional study. OCTA parameters, including the central foveal thickness (CFT), foveal avascular zone (FAZ) area, FAZ perimeter, acircularity index (AI), foveal density (FD300), and the vessel densities (VDs) of the superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris were analyzed in a 6 × 6 mm2 macular scan. Correlation and multiple linear regression analyses were conducted to identify potential systemic characteristics associated with these OCTA metrics. RESULTS: AI (P = 0.034) and FD300 (P < 0.001) differed significantly between the NLR and control groups. The VD of SCP in the parafovea (P = 0.001) and of DCP in both the parafovea (P = 0.011) and perifovea (P = 0.001) were significantly lower in the NLR group than in the control group. In a multiple linear regression analysis, the reduced VD of the perifoveal DCP was significantly correlated with the increased international normalized ratio (standardized beta [STD ß] = - 0.356; P = 0.047). CONCLUSIONS: Macular microvascular changes can be observed during remission from acute leukemia antecedent to clinically visible retinal lesions. Hematological disturbances may be associated with microvascular impairments in preclinical leukemic retinopathy.

Efficacy comparison of anti-vascular endothelial growth factor drugs for the treatment of type 1 retinopathy of prematurity: A network meta-analysis of randomised controlled trials.

PURPOSE: To compare the efficacy of different anti-vascular endothelial growth factor (VEGF) agents for the treatment of retinopathy of prematurity (ROP) in preterm infants. METHODS: Seven databases were searched for eligible literature up to February 22, 2023. Studies were included if they were randomised controlled trials (RCTs) investigating the efficacy of anti-VEGF agents for ROP in infants. A network meta-analysis (NMA) was performed. We also conducted subgroup analyses to determine the efficacy ranking of regimens used in different regions. The odds ratio (OR), standardised mean difference (SMD), and surface under the cumulative ranking curve (SUCRA) were calculated for each outcome. RESULTS: Thirteen RCTs of 10 different regimens, involving 1196 infants (2388 eyes), were identified. Bevacizumab (0.625 mg; OR = 0.16, 95% confidence interval [CI] 0.06-0.40, SUCRA = 80.6%) and conbercept (0.15 mg; OR = 0.08, 95% CI 0.02-0.30, SUCRA = 96.0%) were the most effective regimens in reducing the risk of ROP recurrence requiring retreatment in Western countries and China, respectively. Compared with laser therapy, bevacizumab (0.625 mg; SMD = 1.54, 95% CI 0.06-3.02) achieved significantly longer intervals between treatment and recurrence. No significant difference in the risk of retinal detachment was detected between any anti-VEGF agent and laser (p > 0.05). CONCLUSIONS: Bevacizumab (0.625 mg) and conbercept (0.15 mg) appeared to be the most effective therapies for ROP in Western countries and China, respectively. More high-quality RCTs are warranted to evaluate the efficacy and long-term safety of anti-VEGF drugs for the management of ROP.

Sphingosylphosphorylcholine antagonizes proton-sensing ovarian cancer G-protein-coupled receptor 1 (OGR1)-mediated inositol phosphate production and cAMP accumulation.

Ovarian cancer G-protein-coupled receptor 1 (OGR1), previously proposed as a receptor for sphingosylphosphorylcholine (SPC), has recently been identified as a proton-sensing or extracellular pH-responsive G-protein-coupled receptor stimulating inositol phosphate production, reflecting the activation of phospholipase C. In the present study, we found that acidic pH stimulated cAMP accumulation, reflecting the activation of adenylyl cyclase, in addition to inositol phosphate production in OGR1-expressing cells. The cAMP response was hardly affected by the inhibition of phospholipase C. SPC inhibited the acidification-induced actions in a pH-dependent manner, while no OGR1-dependent agonistic action of SPC was observed. Thus, the dose-response curves of the proton-induced actions were shifted to the right in the presence of SPC regardless of stereoisoform. The antagonistic property was also observed for psychosine and glucosylsphingosine. In conclusion, OGR1 stimulation may lead to the activation of adenylyl cyclase in addition to phospholipase C in response to extracellular acidification but not to SPC. However, SPC and related lysolipids antagonize the proton-induced and OGR1-mediated actions.

Structure-activity relationships of adenosine A3 receptor ligands: new potential therapy for the treatment of glaucoma.

Structure-activity relationships (SAR) of fused 1,2,4-triazolo[1,5-c ]pyrimidine were performed. Various substituents were introduced into the heterocyclic ring to improve the potency of adenosine A(3) receptor binding affinity and A(3)-selectivity against other subtypes. Potent and selective A(3) receptor antagonists were identified and were evaluated in a monkey model of intraocular pressure by eye-drop administration. As a result, compound 1c (OT-7999) was found to significantly decrease intraocular pressure in the animal model.

Facile synthesis of fused 1,2,4-triazolo[1,5-c]pyrimidine derivatives as human adenosine A3 receptor ligands.

A facile synthetic method for fused triazolopyrimidine derivatives having high affinity and selectivity for human adenosine A(3) receptors is reported. The fused triazolopyrimidine derivatives were easily prepared by one-pot reaction using acylhydrazines and imidates prepared from amine derivatives bearing cyano group and orthoesters in situ. This synthetic method was useful in finding new tricyclic adenosine A(3) receptor antagonists and also in diversifying the substituents at two positions on the fused triazolopyrimidine ring.

1,2,4-Triazolo[5,1-i]purine derivatives as highly potent and selective human adenosine A(3) receptor ligands.

A series of triazolopurines showed structural similarity to human adenosine A(3) receptor antagonist, 9-chloro-2-(2-furanyl)-5-[(phenylacetyl)amino][1,2,4]triazolo[1,5-c]quinazoline (MRS 1220, 1). In this study, we found novel 1,2,4-triazolo[5,1-i]purine derivatives (2) showing human adenosine A(3) receptor affinities. The compounds were obtained in two steps from 5-amino-4-cyanoimidazole (33). The affinity was determined in radioligand binding assays for the cloned human adenosine A(1), A(2A), A(2B), and A(3) receptors. After the structure-activity relationship was analyzed, we determined that there was a mild parabolic relationship between the length of alkyl groups at the 5-position and the affinities at the A(3) receptor and positive correlation between the length of the substituents on phenyl groups at the 8-position and the affinities at the A(2A) receptor. These investigations led to potent and selective human adenosine A(3) receptor ligands. The most potent A(3) receptor ligand (5-n-butyl-8-(4-methoxyphenyl)-3H-[1,2,4]triazolo[5,1-i]purine (27, K(i) = 0.18 nM) and the most selective A(3) receptor ligand against A(1), A(2A), and A(2B) receptors, (5-n-butyl-8-(4-n-propoxyphenyl)-3H-[1,2,4]triazolo[5,1-i]purine (29, >19 600), were discovered.