Publications by authors named "Balamurali K Ambati"

Aim: To evaluate the efficacy and stability of haptic sutured in-the-bag intraocular lens (IOL) in eyes with zonular instability.

Methods: A total 60 eyes of 60 patients were included in this retrospective cohort study. Postoperative stability in three groups [haptic sutured IOL in the bag, IOL in the bag insertion with haptics oriented toward areas of zonulysis, IOL with capsular tension ring (CTR) in the bag insertion] were compared according to the IOL insertion methods.

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Among numerous point mutation differences between the SARS-CoV-2 and the bat RaTG13 coronavirus, only the 12-nucleotide furin cleavage site (FCS) exceeds 3 nucleotides. A BLAST search revealed that a 19 nucleotide portion of the SARS.Cov2 genome encompassing the furing cleavage site is a 100% complementary match to a codon-optimized proprietary sequence that is the reverse complement of the human mutS homolog (MSH3).

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The Angiopoietin-1/2 system is an opportune target for therapeutic intervention in a wide range of vascular pathologies, particularly through its association with endothelium. The complex multi-domain structure of native human Angiopoietin-1 has hindered its widespread applicability as a therapeutic agent, prompting the search for alternative approaches to mimicking the Ang1:Tie2 signalling axis; a system with highly complex patterns of regulation involving multiple structurally similar molecules. An engineered variant, Cartilage Oligomeric Matrix Protein - Angiopoietin-1 (COMP-Ang1), has been demonstrated to overcome the limitations of the native molecule and activate the Tie2 pathway with several fold greater potency than Ang1, both in vitro and in vivo.

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A missense mutation of collagen type VIII alpha 2 chain () gene leads to early-onset Fuchs' endothelial corneal dystrophy (FECD), which progressively impairs vision through the loss of corneal endothelial cells. We demonstrate that CRISPR/Cas9-based postnatal gene editing achieves structural and functional rescue in a mouse model of FECD. A single intraocular injection of an adenovirus encoding both the Cas9 gene and guide RNA (Ad-Cas9-Col8a2gRNA) efficiently knocked down mutant expression in corneal endothelial cells, prevented endothelial cell loss, and rescued corneal endothelium pumping function in adult mutant mice.

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Introduction: Diabetic hyperglycemia causes progressive and generalized damage to the microvasculature. In renal glomeruli, this results in the loss of podocytes with consequent loss of constitutive angiopoietin-1 (Ang1) signaling, which is required for stability of the glomerular endothelium. Repeated tail vein injection of adenovirus expressing COMP-Ang1 (a stable bioengineered form of Ang1) was previously reported to improve diabetic glomerular damage despite the liver and lungs being primary targets of adenoviral infection.

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Purpose: Surgical management of keratoconus aims to improve corneal curvature, prevent progression of corneal ectasia, and manage refractive error. In older individuals with concurrent cataracts, management can be challenging due to topographic irregularity and difficult-to-interpret IOL calculations. We describe a sequential combination of two surgical techniques-intrastromal corneal ring segments (e.

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Purpose: Neurotrophic keratopathy is a degenerative disease that may be improved by nerve growth factor (NGF). Our aim was to investigate the use of pergolide, a dopamine (D1 and D2) receptor agonist known to increase the synthesis and release of NGF for regeneration of damaged corneal nerve fibers.

Methods: Pergolide function was evaluated by measuring axon length and NGF levels by enzyme-linked immunosorbent assay in cultured chicken dorsal root ganglion (DRG) cells with serial doses of pergolide (10, 25, 50, 150, and 300 µg/ml) and with different concentrations of a D1 antagonist.

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Degeneration of the retinal pigmented epithelium (RPE) and aberrant blood vessel growth in the eye are advanced-stage processes in blinding diseases such as age-related macular degeneration (AMD), which affect hundreds of millions of people worldwide. Loss of the RNase DICER1, an essential factor in micro-RNA biogenesis, is implicated in RPE atrophy. However, the functional implications of DICER1 loss in choroidal and retinal neovascularization are unknown.

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Purpose: Current treatments for diabetic retinopathy (DR) have considerable limitations, underpinning the need for new therapeutic options. In this article, the ability of an engineered angiopoietin-1 variant (COMP-Ang1) to ameliorate the injurious effects of hyperglycemia on barrier integrity in a human retinal microvascular endothelial cell (HRMvEC) model is comprehensively investigated.

Methods: Confluent HRMvECs were treated (0-72 hours) with d-glucose (5 or 30 mM) in the absence and presence of COMP-Ang1 (10-200 ng/mL).

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Purpose: To describe and evaluate the value of nutritional supplements in the management of age-related macular degeneration (AMD) through a review of the current literature.

Methods: An extensive literature search was performed, and key research articles exploring AREDS and AREDS-2 formulations, genetics, omega fatty acids, calcium and folic acid in high-risk women were reviewed. PubMed and Web of Science databases were used for generating articles to review.

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Purpose: We determine whether intravitreal angiopoietin-1 combined with the short coiled-coil domain of cartilage oligomeric matrix protein by adeno-associated viral serotype 2 (AAV2.COMP-Ang1) delivery following the onset of vascular damage could rescue or repair damaged vascular beds and attenuate neuronal atrophy and dysfunction in the retinas of aged diabetic mice.

Methods: AAV2.

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Herpes zoster ophthalmicus is commonly used to describe viral reactivation from the trigeminal ganglia with ocular involvement. The ophthalmic branch is the most commonly involved, whereas the maxillary and mandibular dermatomes are less commonly affected. Neurotrophic ulcer may occur secondary to intentional or inadvertent damage to the trigeminal nucleus, root, ganglion, or any segment of the ophthalmic branch of this cranial nerve.

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Optical coherence tomography (OCT) angiography is a dye-free and non-invasive angiography which allows visualization of retinal and choroid vascular flow, enabling observation of highly permeable and three dimensional vasculature. Although OCT angiography is providing new insights in human retinal and choroidal diseases, a few studies have been reported in experimental mice. In this study, to determine the potential of OCT angiography in experimental mice, we sought to examine whether OCT angiography can detect vascular change in type I diabetic mice.

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The availability of therapeutics to treat pregnancy complications is severely lacking, mainly due to the risk of harm to the fetus. In placental malaria, infected erythrocytes (IEs) accumulate in the placenta by adhering to chondroitin sulfate A (CSA) on the surfaces of trophoblasts. Based on this principle, we have developed a method for targeted delivery of payloads to the placenta using a synthetic placental CSA-binding peptide (plCSA-BP) derived from VAR2CSA, a CSA-binding protein expressed on IEs.

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Purpose: To evaluate the incidence, related perioperative factors, clinical characteristics, and possible etiologies of epithelial keratitis after cataract surgery.

Methods: A retrospective chart review of 666 eyes in 666 patients who underwent cataract surgery was performed to evaluate the incidence of epithelial keratitis and related factors in the postoperative period.

Results: Postoperative epithelial keratitis developed in 15 eyes.

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Short-activating RNA (saRNA), which targets gene promoters, has been shown to increase the target gene expression. In this study, we describe the use of an saRNA (Flt a-1) to target the flt-1 promoter, leading to upregulation of the soluble isoform of Flt-1 and inhibition of angiogenesis. We demonstrate that Flt a-1 increased sFlt-1 mRNA and protein levels, while reducing VEGF expression.

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Background: Current practice methods are unclear as to the most safe and effective prophylactic pharmacotherapy and method of delivery to reduce postoperative endophthalmitis occurrence.

Methods: A systematic review and meta-analysis using Meta-analysis of Observational Studies in Epidemiology guidelines was performed to compare the efficacy of intracameral cefuroxime, moxifloxacin and vancomycin in preventing postphacoemulsification cataract surgery endophthalmitis. A safety analysis of intracameral antibiotics was concurrently performed.

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Purpose: To describe the epidemiology and prevalence, rates of progression, difference between adult and pediatric populations, and therapeutic approaches to pediatric keratoconus from documented literature.

Methods: A literature search was done on PubMed using key words including pediatric keratoconus, children with keratoconus, adult keratoconus, penetrating keratoplasty, corneal cross-linking and intracorneal ring segments. The literature was reviewed and reported to explore the key epidemiological differences between the pediatric and adult population with regards to presentation and treatment options.

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Aim: To evaluate the effect of sorafenib in murine high risk keratoplasty model.

Methods: Graft survival, corneal neovascularization, and corneal lymphangiogenesis were compared among the sorafenib, dexamethasone, dimethyl sulfoxide (DMSO), and phosphate buffered saline (PBS) groups following subconjunctival injection in mice that underwent high risk penetrating keratoplasty (HRPK). Real-time polymerase chain reaction was performed to quantify the expression of inflammatory cytokines and vascular endothelial growth factor (VEGF)-A, VEGF-C, vascular endothelial growth factor receptor (VEGFR)-2, VEGFR-3.

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We describe clinical applications and surgical techniques for a new type of capsular tension segment (CTS) for use during cataract surgery. The Ambati CTS is distinguished from other CTS devices by having 2 eyelets close to each other, which allows it to distribute tension to 2 points, avoiding too much stress at a single point on the anterior capsulotomy, which prevents peaking of the capsulorhexis, and potentially reducing the risk for anterior capsule tear. Two of these CTS devices could possibly be used to provide 4-point fixation of a capsular bag in eyes with near-complete zonular instability.

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