Quantitative Analysis of Dietary Vitamin A Metabolites in Murine Ocular and Non-Ocular Tissues Using High-Performance Liquid Chromatography.

G protein-coupled receptors (GPCRs) are a superfamily of transmembrane proteins that initiate signaling cascades through activation of its G protein upon association with its ligand. In all mammalian vision, rhodopsin is the GPCR responsible for the initiation of the phototransduction cascade. Within photoreceptors, rhodopsin is bound to its chromophore 11-cis-retinal and is activated through the light-sensitive isomerization of 11-cis-retinal to all-trans-retinal, which activates the transducin G protein, resulting in the phototransduction cascade.

Gender-specific association of rs2371597 polymorphism in keratoconus patients of Saudi origin.

Objective: To investigate the association of specific genetic polymorphisms (rs2371597 in , rs11720822 in , rs387907358 in , and rs77542162 in ) in a Saudi cohort of keratoconus (KC) patients compared to controls.

Methods: A retrospective case-control genetic association study was conducted. The study included 99 KC patients and 193 healthy controls.

Antioxidant and Anti-Inflammatory Effects of Extracts on a Model of Diet-Induced Steatosis.

Oxidative stress and inflammation are widely recognised as factors that can initiate and facilitate the development of MAFLD. The aim of this study is to analyse the effect of low and high doses of var. peel extract (L-OD and H-OD, respectively) and var.

Effects of intravitreal Bevacizumab (Avastin) monotherapy in central retinal vein occlusion in young subjects.

Aim: To evaluate the efficacy of anti-angiogenic agent Bevacizumab in central retinal venous occlusion treatment.

Objectives: To determine the efficacy of Bevacizumab and ophthalmological parameters such as best corrected visual acuity (BCVA) and central macular thickness (CMT) using optical coherence tomography (OCT) in central retinal venous occlusion in patients aged less than 30.

Methods: This is a prospective, interventional study, done on 25 eyes of 25 patients aged 30 years and below with central retinal venous occlusion, who received intravitreal Bevacizumab injections for three consecutive months.

Methodology for Studying Interactions of Vitamin A Membrane Receptors and Opsin Protein with their Ligands in Generating the Retinylidene Protein.

Distribution of dietary vitamin A/all-trans retinol (ROL) throughout the body is critical for maintaining retinoid function in peripheral tissues and generating the retinylidene protein for visual function. RBP4-ROL is the complex of ROL with retinol-binding protein 4 (RBP4), which is present in the blood. Two membrane receptors, Retinol Binding Protein 4 Receptor 2 (RBPR2) in the liver and STimulated by Retinoic Acid 6 Retinol (STRA6) in the eye, bind circulatory RBP4 and this mechanism is critical for internalizing ROL into cells.

The biogeography of the Amazonian tree flora.

We describe the geographical variation in tree species composition across Amazonian forests and show how environmental conditions are associated with species turnover. Our analyses are based on 2023 forest inventory plots (1 ha) that provide abundance data for a total of 5188 tree species. Within-plot species composition reflected both local environmental conditions (especially soil nutrients and hydrology) and geographical regions.

Two decades of clear-cutting threats in the Brazilian Amazonian protected areas around the Jirau, Santo Antônio, and Belo Monte large dams.

Deforestation rates in the Amazon have markedly increased in the last few years, affecting non-protected and protected areas (PAs). Brazil is a hotspot of Protected Area Downgrading, Downsizing, and Degazettement (PADDD) events, with most events associated with infrastructure projects. Despite the threats dams impose on PAs, there is a knowledge gap in assessing deforestation in PAs around large dams in the Amazon.

ε2-Carriers Are Associated with an Increased Risk of Primary Angle-Closure Glaucoma in Patients of Saudi Origin.

This study investigated the association between apolipoprotein E () gene polymorphisms (rs429358 and rs7412) and primary angle-closure glaucoma (PACG) and pseudoexfoliation glaucoma (PXG) in a Saudi cohort. Genotyping of 437 DNA samples (251 controls, 92 PACG, 94 PXG) was conducted using PCR-based Sanger sequencing. The results showed no significant differences in the allele and genotype frequencies of rs429358 and rs7412 between the PACG/PXG cases and controls.

The Logistical Backbone of Photoreceptor Cell Function: Complementary Mechanisms of Dietary Vitamin A Receptors and Rhodopsin Transporters.

In this review, we outline our current understanding of the mechanisms involved in the absorption, storage, and transport of dietary vitamin A to the eye, and the trafficking of rhodopsin protein to the photoreceptor outer segments, which encompasses the logistical backbone required for photoreceptor cell function. Two key mechanisms of this process are emphasized in this manuscript: ocular and systemic vitamin A membrane transporters, and rhodopsin transporters. Understanding the complementary mechanisms responsible for the generation and proper transport of the retinylidene protein to the photoreceptor outer segment will eventually shed light on the importance of genes encoded by these proteins, and their relationship on normal visual function and in the pathophysiology of retinal degenerative diseases.

Topiramate-induced ocular complications: case series.

Unlabelled: Several ocular adverse effects have been attributed to Topiramate, a sulfonamide derivative. It can cause problems in the eye such as choroidal effusion syndrome, acute angle closure glaucoma, myopic shift, visual field defects, and Myokymia. If not identified early, it can be vision-threatening.

Intrauterine Transfusion for Rhesus Alloimmunization: A Historical Retrospective Cohort from A Single Reference Center in Brazil.

This study aimed to describe the historical experience of a single reference center in Brazil with intrauterine transfusion (IUT) for Rhesus (Rh) alloimmunization, evaluating the major complications and the perinatal outcomes of this procedure. This retrospective cohort study evaluated data from medical records of pregnant women between 20 and 34 weeks of gestation whose fetuses underwent IUT by cordocentesis between January 1991 and June 2021. The same experienced examiner performed all procedures.

The Clinical Findings, Pathogenic Variants, and Gene Therapy Qualifications Found in a Leber Congenital Amaurosis Phenotypic Spectrum Patient Cohort.

This retrospective study examines the clinical characteristics and underlying genetic variants that exist in a Leber congenital amaurosis (LCA) patient cohort evaluated at the inherited retinal disease (IRD) clinic at the University of Minnesota (UMN)/M Health System. Our LCA cohort consisted of 33 non-syndromic patients and one patient with Joubert syndrome. We report their relevant history, clinical findings, and genetic testing results.

Common Variants rs429358 and rs7412 in Gene Are Not Associated with POAG in a Saudi Cohort.

Adult-onset glaucoma, an age-related neurodegenerative disease, is very prevalent among the elderly Arabs of Saudi origin. This study investigated the association between apolipoprotein E () gene variants (rs429358 and rs7412) and primary open-angle glaucoma (POAG) in Arabs of Saudi origin. A case-control genetic association study involving 179 POAG patients and 251 controls utilized Sanger sequencing to genotype gene variants.

Postoperative CSF Leak: Blood Patch-A New Avenue.

 Cerebrospinal fluid leak (CSF) after a neurosurgical procedure is a known complication that may result in bad outcomes (1). The incidence of CSF leak varies based on the site involved; it ranges from 4 to 32% for transsphenoidal to posterior fossa procedures. The costs involved in treating postoperative CSF leaks increases exponentially that becomes a barrier in continuing optimum treatment.

Association between Polymorphism rs61876744 in Gene and Keratoconus in a Saudi Cohort.

The genetic etiology of Keratoconus (KC) in Middle Eastern Arabs of Saudi origin is still unclear. A recent genome-wide study identified two significant loci in the region of (rs61876744) and (rs138380) for KC that may be associated with KC in the Saudi population. In addition, polymorphisms in the apolipoprotein E () gene, namely, rs429358 and rs7412, responsible for allelic variants ε2, ε3, and ε4, may influence KC via oxidative stress mechanism(s).

Fabrication of facially guided CAD-CAM complete dentures: A dental technique.

An alternative protocol is presented to design computer-aided design and computer-aided manufacturing (CAD-CAM) complete dentures and overdentures using a facially guided digital design. The facially guided design protocol with CAD-CAM facilitated communication between the clinician and dental laboratory technician. A monolithic denture and overdenture were fabricated guided by preliminary dentures with 3-dimensionally (3D) printed denture bases and milled wax teeth.

Mapping density, diversity and species-richness of the Amazon tree flora.

Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness.

Data-Sparse Prediction of High-Risk Schools for Lead Contamination in Drinking Water: Examples from Four U.S. States.

Childhood lead exposure through drinking water has long-term effects on cognition and development, and is a significant public health concern. The comprehensive lead testing of public schools entails high expense and time. In prior work, random forest modeling was used successfully to predict the likelihood of lead contamination in the drinking water from schools in the states of California and Massachusetts.

More than 10,000 pre-Columbian earthworks are still hidden throughout Amazonia.

Indigenous societies are known to have occupied the Amazon basin for more than 12,000 years, but the scale of their influence on Amazonian forests remains uncertain. We report the discovery, using LIDAR (light detection and ranging) information from across the basin, of 24 previously undetected pre-Columbian earthworks beneath the forest canopy. Modeled distribution and abundance of large-scale archaeological sites across Amazonia suggest that between 10,272 and 23,648 sites remain to be discovered and that most will be found in the southwest.

Improvement in the Stability and Bioaccessibility of Carotenoid and Carotenoid Esters from a Papaya By-Product Using O/W Emulsions.

The aim of the present work was to improve the stability and bioaccessibility of carotenoids from green oil extracts obtained from papaya by-products using oil-in-water (O/W) emulsions. The effects of different concentrations of pectin (1%, 2%, and 3%), a high-molecular-size emulsifier, together with Tween 20, a low-molecular-size emulsifier, high-speed homogenization conditions (time: 2, 3, 4, and 5 min; rpm: 9500, 12,000, 14,000, and 16,000 rpm), and high-pressure homogenization (HPH) (100 MPa for five cycles) were evaluated to determine the optimal conditions for obtaining O/W stable emulsions with encapsulated carotenoids. Soybean, sunflower, and coconut oils were used to formulate these O/W emulsions.

Clinical Characteristics and Genetic Variants of a Large Cohort of Patients with Retinitis Pigmentosa Using Multimodal Imaging and Next Generation Sequencing.

This retrospective study identifies patients with RP at the Inherited Retinal Disease Clinic at the University of Minnesota (UMN)/M Health System who had genetic testing via next generation sequencing. A database was curated to record history and examination, genetic findings, and ocular imaging. Causative pathogenic and likely pathogenic variants were recorded.