Consensus Recommendations for Studies of Outflow Facility and Intraocular Pressure Regulation Using Ex Vivo Perfusion Approaches.

Intraocular pressure (IOP) elevation is the primary risk factor and currently the main treatable factor for progression of glaucomatous optic neuropathy. In addition to direct clinical and living animal in vivo studies, ex vivo perfusion of anterior segments and whole eyes is a key technique for studying conventional outflow function as it is responsible for IOP regulation. We present well-tested experimental details, protocols, considerations, advantages, and limitations of several ex vivo model systems for studying IOP regulation.

In vivo scanning laser fundus and high-resolution OCT imaging of retinal ganglion cell injury in a non-human primate model with an activatable fluorescent-labeled TAT peptide probe.

The optical imaging agent TcapQ488 has enabled imaging of retinal ganglion cell (RGC) injury in vivo in rodents and has potential as an effective diagnostic probe for early detection and intervention monitoring in glaucoma patients. In the present study, we investigated TcapQ488 in non-human primates (NHPs) to identify labeling efficacy and early signals of injured RGC, to determine species-dependent changes in RGC probe uptake and clearance, and to determine dose-limiting toxicities. Doses of 3, 6, and 12 nmol of TcapQ488 were delivered intravitreally to normal healthy NHP eyes and eyes that had undergone hemiretinal endodiathermy axotomy (HEA) in the inferior retina.

Development of Microcystoid Macular Degeneration in the Retina of Nonhuman Primates: Time-Course and Associated Pathologies.

Purpose: Microcystoid macular degeneration (MMD) is a condition where cystoid vacuoles develop within the inner nuclear layer of the retina in humans in a variety of disorders. Here we report the occurrence of MMD in non-human primates (NHPs) with various retinal ganglion cell (RGC) pathologies and evaluate the hypothesis that MMD does not precede RGC loss but follows it.

Methods: Morphological studies were performed of the retinas of NHPs, specifically both rhesus () and cynomolgus macaques (), in which MMD was identified after induction of experimental glaucoma (EG), hemiretinal endodiathermy axotomy (HEA), and spontaneous idiopathic bilateral optic atrophy.

Sex as a risk factor regarding presbyopia in the rhesus monkey.

Purpose: To determine the effect of sex as a risk factor regarding presbyopia.

Methods: Maximum accommodation was pharmacologically induced (40% cabachol corneal iontophoresis) in 97 rhesus monkeys (49 males and 48 females) ranging in age from 8 to 36 years old. Accommodation was measured by Hartinger coincidence refractometry.

Nucleolus and centromere TSA-Seq reveals variable localization of heterochromatin in different cell types.

Genome differential positioning within interphase nuclei remains poorly explored. We extended and validated TSA-seq to map genomic regions near nucleoli and pericentric heterochromatin in four human cell lines. Our study confirmed that smaller chromosomes localize closer to nucleoli but further deconvolved this by revealing a preference for chromosome arms below 36-46 Mbp in length.

The nuclear bodies conference: Hubs of genomic activity, June 24-28, Western Shore, Nova Scotia, Canada.

This conference brought together leaders in the investigation of various bodies that populate the nucleus, a field that complements research on chromosome biology. These nuclear bodies had been receiving increasing attention as hubs of genome activity and the new findings reported at the conference strongly confirmed and significantly expanded this principle.

Accommodative movements of the choroid in the optic nerve head region of human eyes, and their relationship to the lens.

The ciliary muscle (CM) powers the accommodative response, and during accommodation the CM pulls the choroid forward in the region of the ora serrata. Our goal was to elucidate the accommodative movements of the choroid in the optic nerve region in humans and to determine whether these movements are related to changes in the lens dimensions that occur with aging, in the unaccommodated and accommodated state. Both eyes of 12 human subjects (aged 18-51 yrs) were studied.

Intraocular accommodative movements in monkeys; relationship to presbyopia.

Our goal was to quantify the age-related changes in the dynamic accommodative movements of the vitreous and aqueous humor in iridic, aniridic, phakic and aphakic primate eyes. Six bilaterally iridic and four bilaterally iridectomized rhesus monkeys, ranging in age from 6 to 25 years, received a stimulating electrode in the midbrain Edinger-Westphal nucleus to induce accommodation, measured by a Hartinger coincidence refractometer. One of the four iridectomized monkeys underwent unilateral extracapsular and another monkey underwent intracapsular lens extraction.

Consensus Recommendation for Mouse Models of Ocular Hypertension to Study Aqueous Humor Outflow and Its Mechanisms.

Due to their similarities in anatomy, physiology, and pharmacology to humans, mice are a valuable model system to study the generation and mechanisms modulating conventional outflow resistance and thus intraocular pressure. In addition, mouse models are critical for understanding the complex nature of conventional outflow homeostasis and dysfunction that results in ocular hypertension. In this review, we describe a set of minimum acceptable standards for developing, characterizing, and utilizing mouse models of open-angle ocular hypertension.

Report: The effects of topical pleurotus tuberregium (PT) aqueous extract on intraocular pressure in monkeys.

Purpose: In earlier experiments in Nigeria, aqueous extract of Pleurotus tuber-regium (PT) had been shown to lower intra ocular pressure (IOP) in a feline model. The aim of the current study was to determine whether PT had the same or a similar IOP-lowering effect in ocularly normal non-human primates.

Methods: Four monkeys were treated twice daily for 4 days with 2 x 20 μl drops of 50 mg/ml PT (pH = 4.

The chromatin-binding domain of Ki-67 together with p53 protects human chromosomes from mitotic damage.

Vertebrate mammals express a protein called Ki-67 which is most widely known as a clinically useful marker of highly proliferative cells. Previous studies of human cells indicated that acute depletion of Ki-67 can elicit a delay at the G1/S boundary of the cell cycle, dependent on induction of the checkpoint protein p21. Consistent with those observations, we show here that acute Ki-67 depletion causes hallmarks of DNA damage, and the damage occurs even in the absence of checkpoint signaling.

Close to the edge: Heterochromatin at the nucleolar and nuclear peripheries.

Chromatin is a dynamic structure composed of DNA, RNA, and proteins, regulating storage and expression of the genetic material in the nucleus. Heterochromatin plays a crucial role in driving the three-dimensional arrangement of the interphase genome, and in preserving genome stability by maintaining a subset of the genome in a silent state. Spatial genome organization contributes to normal patterns of gene function and expression, and is therefore of broad interest.

Deconstructing aqueous humor outflow - The last 50 years.

Herein partially summarizes one scientist-clinician's wanderings through the jungles of primate aqueous humor outflow over the past ~45 years. Totally removing the iris has no effect on outflow facility or its response to pilocarpine, whereas disinserting the ciliary muscle (CM) from the scleral spur/trabecular meshwork (TM) completely abolishes pilocarpine's effect. Epinephrine increases facility in CM disinserted eyes.

Distinct features of nucleolus-associated domains in mouse embryonic stem cells.

Heterochromatin in eukaryotic interphase cells frequently localizes to the nucleolar periphery (nucleolus-associated domains (NADs)) and the nuclear lamina (lamina-associated domains (LADs)). Gene expression in somatic cell NADs is generally low, but NADs have not been characterized in mammalian stem cells. Here, we generated the first genome-wide map of NADs in mouse embryonic stem cells (mESCs) via deep sequencing of chromatin associated with biochemically purified nucleoli.

Two contrasting classes of nucleolus-associated domains in mouse fibroblast heterochromatin.

In interphase eukaryotic cells, almost all heterochromatin is located adjacent to the nucleolus or to the nuclear lamina, thus defining nucleolus-associated domains (NADs) and lamina-associated domains (LADs), respectively. Here, we determined the first genome-scale map of murine NADs in mouse embryonic fibroblasts (MEFs) via deep sequencing of chromatin associated with purified nucleoli. We developed a Bioconductor package called and demonstrated that it identifies NADs more accurately than other peak-calling tools, owing to its critical feature of chromosome-level local baseline correction.

Early adoption of the fluocinolone acetonide (FAc) intravitreal implant in patients with persistent or recurrent diabetic macular edema (DME).

To assess long-term outcomes for effectiveness, safety, and treatment burden after injection of 0.2 µg/day fluocinolone acetonide [FAc] intravitreal implant (ILUVIEN) in patients with persistent or recurrent diabetic macular edema (DME) and 6-18 months of follow-up. Retrospective case series in 18 eyes (13 patients) treated with the FAc implant.

Correction to: Novel genetic tools for probing individual H3 molecules in each nucleosome.

In the original publication, Fig. 1 was incorrectly published. The amino acid sequence was shifted to the left relative to the rest of the diagram in the published version and the corrected figure is given here.

Novel genetic tools for probing individual H3 molecules in each nucleosome.

In eukaryotes, genomic DNA is packaged into the nucleus together with histone proteins, forming chromatin. The fundamental repeating unit of chromatin is the nucleosome, a naturally symmetric structure that wraps DNA and is the substrate for numerous regulatory post-translational modifications. However, the biological significance of nucleosomal symmetry until recently had been unexplored.

SB772077B, A New Rho Kinase Inhibitor Enhances Aqueous Humour Outflow Facility in Human Eyes.

We investigated the effect of a new Rho kinase inhibitor, SB772077B (SB77) on aqueous outflow facility (OF) in human eyes using human organ-cultured anterior segment (HOCAS). IOP was monitored for 24 h post-treatment with either SB77 (0.1/10/50 µM) or vehicle after a stable baseline pressure.

Effects of Lentivirus-Mediated C3 Expression on Trabecular Meshwork Cells and Intraocular Pressure.

Purpose: We evaluated the effects of lentivirus-mediated exoenzyme C3 transferase (C3) expression on cultured primary human trabecular meshwork (HTM) cells in vitro, and on rat intraocular pressure (IOP).

Methods: HTM cells were cultured and treated with lentivirus vectors expressing either green fluorescent protein (GFP) only (LV-GFP) or GFP and C3 together (LV-C3-GFP). Changes in cell morphology and actin stress fibers were assessed.

Glaucoma Drugs in the Pipeline.

Glaucoma is a chronic disease that can be challenging to treat for both patients and physicians. Most patients will require more than 1 medication over time to maintain their intraocular pressure (IOP) at a physiologically benign level. Patients may become refractory to existing compounds and many struggle with adherence to multiple topical drop regimens.