Publications by authors named "Narendran S"

Objective: This study evaluated the RID-MyC (Rapid Identification of Mycoses using clustered regularly interspaced short palindromic repeats [CRISPR]) assay, a CRISPR/Cas12a-based diagnostic tool, for its efficacy in diagnosing fungal endophthalmitis (FE) compared with panfungal polymerase chain reaction (PCR) and culture methods.

Design: A comparative cross-sectional study assessing the performance of the RID-MyC assay against established diagnostic modalities for FE.

Subjects: The study included 133 intraocular samples from 117 patients with suspected microbial endophthalmitis.

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Aims: This report summarizes clinical findings, diagnosis, management, and long term outcomes of a recalcitrant and keratitis.

Methods And Materials: An otherwise healthy male patient presented with a corneal infiltrate with predominantly fungal characteristics, but atypical in terms of progression. The infiltrate remained undiagnosed even after several scrapings, and aqueous tap cultures.

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Inflammasome activation is implicated in diseases of aberrant angiogenesis such as age-related macular degeneration (AMD), though its precise role in choroidal neovascularization (CNV), a characteristic pathology of advanced AMD, is ill-defined. Reports on inhibition of inflammasome constituents on CNV are variable and the precise role of inflammasome in mediating pathological angiogenesis is unclear. Historically, subretinal injection of inflammasome agonists alone has been used to investigate retinal pigmented epithelium (RPE) degeneration, while the laser photocoagulation model has been used to study pathological angiogenesis in a model of CNV.

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Article Synopsis
  • The study examined the occurrence and characteristics of hemifacial spasm (HFS) in 85 patients at a South Indian eye care center, focusing on potential links to systemic diseases.
  • The average age of patients was around 56 years, with a majority experiencing left-side involvement and primary HFS; MRI showed neurovascular conflicts in some cases.
  • The findings suggested a significant association between HFS and hypertension, indicating that further research is needed to clarify this relationship.
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Article Synopsis
  • - The study aimed to create a quick and accurate CRISPR-based test called RID-MyC for identifying fungal infections, specifically fungal keratitis, comparing it to traditional diagnostic methods.
  • - Conducted with 142 patients in South India, the RID-MyC assay uses advanced molecular techniques to amplify and detect fungal DNA, showing strong agreement with existing diagnostic approaches.
  • - Results demonstrated high sensitivity (93.27%) and specificity (89.47%) for diagnosing fungal keratitis, significantly reducing diagnostic time to about 50 minutes, highlighting its potential as an effective diagnostic tool.
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Purpose: Adult stem cells (SCs) with self-renewal and multilineage potential have been reported upon culturing human retinal pigment epithelial (RPE) cells. The current study aimed to identify the location of SCs in human RPE and to elucidate the age-related changes.

Methods: Peripheral, equatorial, and central RPE cells from donors of three age groups were analyzed for their sphere-forming, clonal, and label-retaining cell properties.

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Therapeutic management of inflammation in infectious keratitis (IK) requires new strategy and targets for selective immunomodulation. Targeting host cell-type specific inflammatory responses might be a viable strategy to curtail unnecessary inflammation and reduce tissue damage without affecting pathogen clearance. This study explores the possibility of pathogen and host cell-type dependent differences in the inflammatory pathways relevant in the pathogenesis of IK.

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The aim of this study was to investigate whether the use of nucleoside reverse transcriptase inhibitors (NRTIs) impacts the incidence of prediabetes or type 2 diabetes mellitus (T2DM) or the progression from prediabetes to T2DM in people living with HIV (PLWH). We conducted a retrospective cohort study using the U.S.

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Checkpoint inhibitors can be a highly effective antitumor therapy but only to a subset of patients, presumably due to immunotherapy resistance. Fluoxetine was recently revealed to inhibit the NLRP3 inflammasome, and NLRP3 inhibition could serve as a target for immunotherapy resistance. Therefore, we evaluated the overall survival (OS) in patients with cancer receiving checkpoint inhibitors combined with fluoxetine.

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Purpose: Rhegmatogenous retinal detachment (RRD) is a vision-threatening event that benefits from surgical intervention. While awaiting surgical reattachment, irreversible hypoxic and inflammatory damage to the retina often occurs. An interim therapy protecting photoreceptors could improve functional outcomes.

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This work aims to classify normal and carcinogenic cells in the oral cavity using two different approaches with an eye towards achieving high accuracy. The first approach extracts local binary patterns and metrics derived from a histogram from the dataset and is fed to several machine-learning models. The second approach uses a combination of neural networks as a backbone feature extractor and a random forest for classification.

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Purpose: To report the outcomes of cataract surgery in patients with Human Immunodeficiency Virus (HIV) infection. Setting Tertiary care ophthalmic hospital DESIGN: Retrospective study METHODS: This study included all eyes of patients with known HIV infection undergoing cataract surgery with a minimum follow-up of 6 months between January 2017 and December 2020. Patients who underwent combined surgeries and pediatric patients were excluded from analysis.

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Subretinal injection (SRI) is a widely used technique in retinal research and can be used to deliver nucleic acids, small molecules, macromolecules, viruses, cells or biomaterials such as nanobeads. Here we describe how to undertake SRI of mice. This protocol was adapted from a technique initially described for larger animals.

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Phacoemulsification is routinely performed with the patient lying supine on the surgical table with his or her head flat and facing the overhead microscope. This routine technique can be a challenge in medical conditions such as kyphosis, scoliosis, orthopnea, Meniere's disease, and CNS abnormality. Some cardiovascular and respiratory conditions make the patients breathless when they lie down, whereas other neurological and spinal problem patients are also equally uncomfortable.

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Article Synopsis
  • The study evaluates the learning curve for subretinal injection (SRI) in mice, focusing on the success rates of trained ophthalmic surgeons from 2018 to 2020.
  • Results show a low initial success rate of 27% for the first 50 cases, improving significantly to 99.32% after around 364 cases, highlighting the difficulty of mastering this technique.
  • The findings suggest that implementing a systematic training approach could enhance consistency in SRI experiments and aid in better interpretation of results related to drug delivery and gene therapy.
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Detection of microbial products by multiprotein complexes known as inflammasomes is pivotal to host defense against pathogens. Nucleotide-binding domain leucine-rich repeat (NLR) CARD domain containing 4 (NLRC4) forms an inflammasome in response to bacterial products; this requires their detection by NLR family apoptosis inhibitory proteins (NAIPs), with which NLRC4 physically associates. However, the mechanisms underlying sterile NLRC4 inflammasome activation, which is implicated in chronic noninfectious diseases, remain unknown.

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The atrophic form of age-related macular degeneration (dry AMD) affects nearly 200 million people worldwide. There is no Food and Drug Administration (FDA)-approved therapy for this disease, which is the leading cause of irreversible blindness among people over 50 y of age. Vision loss in dry AMD results from degeneration of the retinal pigmented epithelium (RPE).

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Long interspersed nuclear element-1 (L1)–mediated reverse transcription (RT) of RNA into cytoplasmic complementary DNA (cDNA) has been implicated in retinal pigmented epithelium (RPE) degeneration. The mechanism of cDNA–induced cytotoxicity and its relevance to human disease are unknown. Here we report that cDNA is highly enriched in the RPE of human eyes with geographic atrophy, an untreatable form of age-related macular degeneration.

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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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Nonfibrillar amyloid-β oligomers (AβOs) are a major component of drusen, the sub-retinal pigmented epithelium (RPE) extracellular deposits characteristic of age-related macular degeneration (AMD), a common cause of global blindness. We report that AβOs induce RPE degeneration, a clinical hallmark of geographic atrophy (GA), a vision-threatening late stage of AMD that is currently untreatable. We demonstrate that AβOs induce activation of the NLRP3 inflammasome in the mouse RPE in vivo and that RPE expression of the purinergic ATP receptor P2RX7, an upstream mediator of NLRP3 inflammasome activation, is required for AβO-induced RPE degeneration.

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retroelements propagate via retrotransposition by hijacking long interspersed nuclear element-1 (L1) reverse transcriptase (RT) and endonuclease activities. Reverse transcription of RNA into complementary DNA (cDNA) is presumed to occur exclusively in the nucleus at the genomic integration site. Whether cDNA is synthesized independently of genomic integration is unknown.

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Innate immune signaling through the NLRP3 inflammasome is activated by multiple diabetes-related stressors, but whether targeting the inflammasome is beneficial for diabetes is still unclear. Nucleoside reverse-transcriptase inhibitors (NRTI), drugs approved to treat HIV-1 and hepatitis B infections, also block inflammasome activation. Here, we show, by analyzing five health insurance databases, that the adjusted risk of incident diabetes is 33% lower in patients with NRTI exposure among 128,861 patients with HIV-1 or hepatitis B (adjusted hazard ratio for NRTI exposure, 0.

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Background: Despite limited and conflicting evidence, hydroxychloroquine, alone or in combination with azithromycin, is widely used in COVID-19 therapy.

Methods: We performed a retrospective study of electronic health records of patients hospitalized with confirmed SARS-CoV-2 infection in US Veterans Health Administration medical centers between March 9, 2020 and April 29, 2020. Patients hospitalized within 24 h of diagnosis were classified based on their exposure to hydroxychloroquine alone (HC) or with azithromycin (HC+AZ) or no HC as treatments.

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