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Purpose: Human ocular tissue banking plays an important part in the advancement of translational research for identifying the molecular processes involved in disease etiology and pathogenesis. Timely obtaining a good‑quality ocular tissue from a cadaveric donor is exceedingly difficult, especially in remote areas, with a variable transportation time (within 12–24 h), raising concerns about RNA quality and its subsequent applications. Therefore, we assessed the utility of retinal tissues from cadaver donor and enucleated eyes based on the RNA quality and gene expression by real‑time polymerase chain reaction (PCR). Settings and Design: Prospective study. Methods: Retina tissues were separated from the donor/ enucleated eyes received in the eye bank within 24 h of death (n = 15) and within an hour from OR (n = 3), respectively, and stored immediately at ‑80 degree. RNA was isolated using trizol, and the quantity and quality were assessed using Qubit and agarose gel electrophoresis, respectively. QPCR was performed for measuring the expression of different retinal‑specific genes. The cellular viability of the retina was assessed by establishing explant primary cell cultures. Statistical Analysis: The data were calculated as an average of normalised Ct values ± standard error of the mean. Results: RNA obtained from cadaveric tissues despite being partially degraded showed a uniform strong gene expression of several retinal‑specific genes such as PAX6, RHO, TUBB3, CRX, and ALDH1L1. The primary cultures established from cadaveric tissues showed viable cells. Conclusion: The cadaver donor tissues collected within 24 hours of death can be effectively utilized for gene expression profiling. [ABSTRACT FROM AUTHOR]

Traboulsi syndrome is a rare autosomal recessive genetic disorder. The present study aimed to identify the pathogenic variants in the ASPH gene responsible for a rare and unique presentation of Traboulsi syndrome associated with cardiac disorder. DNA was isolated from the blood samples from 3 clinically diagnosed Traboulsi syndrome patients (n = 3) after obtaining a prior-informed consent. All three had classical ocular and facial dysmorphic features, and two of them also had associated cardiac problems. Mutation screening was performed for the exons of ASPH gene by Sanger sequencing in these patients and 350 controls. Sequence data analysis was performed using Seqscape and insilico protein analysis by SIFT, PyMOL, and Dynamut softwares. A novel homozygous variant(c.1853 T > A) in exon 21 was identified by Sanger sequencing in two of the three cases while a known pathogenic variant in exon 25 was identified in the third proband. The novel nonsense variant in exon 21 results in a premature truncation of gene resulting in a protein of 543 amino acids. This variant is not reported in ExAC, dbSNP and 1000 genome databases. Both the patients harboring this novel variant, had a unique presentation of Traboulsi syndrome with cardiac dysfunction. In silico analysis predicted the mutation to affect the calcium-binding activity of the gene which might explain the associated cardiac dysfunction in these two patients. The novel pathogenic mutation displayed a perfect genotype-phenotype correlation in two probands of Traboulsi syndrome with cardiac dysfunction. [ABSTRACT FROM AUTHOR]

Cellular hypoxia is a major cause of oxidative stress, culminating in neuronal damage in neurodegenerative diseases. Numerous ex vivo studies have implicated that hypoxia episodes leading to disruption of Ca2+ homeostasis and redox status contribute to the progression of various neuropathologies and cell death. Isolation and maintenance of primary cell culture being cost-intensive, the details of the time course relationship between Ca2+ overload, L-type Ca2+ channel function, and neurite retraction under chronic and long-term hypoxia remain undefined. In order to explore the effect of oxidative stress and Ca2+ overload on neurite length, first, we developed a 5-day-long neurite outgrowth model using N2a cell line. Second, we propose a chronic hypoxia model to investigate the modulation of the L-type Ca2+ channel (Cav1.2) and oxidative resistance gene (OXR1) expression level during the process of neurite retraction and neuronal damage over 32 h. Thirdly, we developed a framework for quantitative analysis of cytosolic Ca2+, superoxide formation, neurite length, and constriction formation in individual cells using live imaging that provides an understanding of molecular targets. Our findings suggest that an increase in cytosolic Ca2+ is a feature of an early phase of hypoxic stress. Further, we demonstrate that augmentation in the L-type channel leads to amplification in Ca2+ overload, ROS accumulation, and a reduction in neurite length during the late phase of hypoxic stress. Next, we demonstrated that non-prophylactic treatment of resveratrol leads to the reduction of calcium overloading under chronic hypoxia via lowering of L-type channel expression. Finally, we demonstrate that resveratrol-mediated reduction of Cav1.2 channel and STAT3 expression are associated with retention of neurite integrity. The proposed in vitro model assumes significance in the context of drug designing and testing that demands monitoring of neurite length and constriction formations by imaging before animal testing. [Display omitted] • Development of a cost-effective neurite outgrowth model for in vitro studies on neurite retraction. • AsSessment of neurite integrity and overall neuronal circuit through quantification of neurite length. • Non-prophylactic treatment of RSV leads to the reduction of Ca2+ overloading under hypoxia via lowering of Cav1.2 expression. • RSV mediated reduction of Cav1.2 and STAT3 expression is associated with retention of neurite integrity. [ABSTRACT FROM AUTHOR]