Publications by authors named "Shanmugam Sumathi"

Purpose: Studies have suggested that photoreceptors (PR) are altered by diabetes, contributing to diabetic retinopathy (DR) pathology. Here, we explored the effect of diabetes on retinal ischemic injury.

Methods: Retinal ischemia-reperfusion (IR) injury was caused by elevation of intraocular pressure in 10-week-old BKS db/db type 2 diabetes mellitus (T2DM) mice or C57BL/6J mice at 4 or 12 weeks after streptozotocin (STZ)-induced type 1 diabetes mellitus (T1DM), and respective nondiabetic controls.

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Introduction: Understanding the emotional intelligence (EI) and self-esteem of Indian and Saudi nursing students is important because their future nurse-patient relationships may be influenced by factors related to their unique cultural contexts. Hence, this study sought to investigate the EI and self-esteem of nursing students in Saudi Arabia and India.

Methods: A descriptive-comparative research design was used to compare 660 nursing students from Saudi Arabia and India who were enrolled in the study from September 2022 to January 2023.

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Introduction: Nursing students frequently encounter the challenge of balancing their studies with the demanding requirements of hands-on practice and this can greatly affect their mental wellbeing. This study aimed to investigate the impact of sleep and psychological well-being on the academic and clinical performance of nursing students in Saudi Arabia.

Methods: This study used a cross-sectional approach with 218 student nurses selected through convenience sampling from King Khalid University, Abha, Saudi Arabia.

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The retinal pigment epithelium (RPE) maintains photoreceptor viability and function, completes the visual cycle, and forms the outer blood-retinal barrier (oBRB). Loss of RPE function gives rise to several monogenic retinal dystrophies and contributes to age-related macular degeneration. Retinal detachment (RD) causes separation of the neurosensory retina from the underlying RPE, disrupting the functional and metabolic relationships between these layers.

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Article Synopsis
  • This study focuses on improving the photocatalytic efficiency of bulk graphitic carbon nitride (g-CN) for wastewater treatment by using a method called thermal exfoliation (TE-g-CN) to enhance its properties.
  • The TE-g-CN demonstrated high degradation efficiencies for various textile dyes after 60 minutes of UV light exposure, achieving 92% for methylene blue, 93% for methyl orange, and 95% for rhodamine B, with performance improving at higher exfoliation temperatures.
  • Characterization techniques showed that TE-g-CN had a significantly larger surface area and higher adsorption efficiency compared to bulk g-CN, along with reduced electron-hole recombination and excellent stability
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Introduction: Clinical trials demonstrated that co-targeting angiopoietin-2 (Ang-2) and vascular endothelial growth factor (VEGF-A) with faricimab controls anatomic outcomes and maintains vision improvements, with strong durability, through 2 years in patients with neovascular age-related macular degeneration and diabetic macular edema. The mechanism(s) underlying these findings is incompletely understood and the specific role that Ang-2 inhibition plays requires further investigation.

Methods: We examined the effects of single and dual Ang-2/VEGF-A inhibition in diseased vasculatures of JR5558 mice with spontaneous choroidal neovascularization (CNV) and in mice with retinal ischemia/reperfusion (I/R) injuries.

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The current study focuses on the incorporation of natural polymers (gelatin, silk fibre) and synthetic (polyvinyl alcohol) polymer towards the fabrication of a novel composite for bone tissue engineering. The Electrospinning method was used to fabricate the novel gelatin/polyvinyl alcohol/silk fibre scaffold. XRD, FTIR and SEM-EDAX analysis was performed to characterize the composite.

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Objectives: To analyse the impact on mental health of the lockdown forced by the coronavirus disease-2019 pandemic.

Methods: This descriptive, cross-sectional study was conducted in Aseer, Saudi Arabia, in May and June 2020, and comprised adult natives of either gender ho could read and write Arabic. Data was collected using a self-developed questionnaire which was distributed online via Google Forms.

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Luminescent yttrium phosphate is engineered into an environmentally benign near infrared (NIR) reflective yellow pigment by the substitution of bismuth and vanadium metals in the host lattice. A series of YPV O ( = 0, 0.05, 0.

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Background: Several retinal pathologies exhibit both inflammation and breakdown of the inner blood-retinal barrier (iBRB) resulting in vascular permeability, suggesting that treatments that trigger resolution of inflammation may also promote iBRB restoration.

Methods: Using the mouse retinal ischemia-reperfusion (IR) injury model, we followed the time course of neurodegeneration, inflammation, and iBRB disruption and repair to examine the relationship between resolution of inflammation and iBRB restoration and to determine if minocycline, a tetracycline derivative shown to reverse microglial activation, can hasten these processes.

Results: A 90-min ischemic insult followed by reperfusion in the retina induced cell apoptosis and inner retina thinning that progressed for approximately 2 weeks.

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Triclosan (TCS) is a common anti-microbial ingredient in pharmaceutical and personal care products. The usage of TCS was banned by the United States Food and Drug Administration (in 2016) due to its potential health risks. However, TCS has been frequently detected in the aquatic environment.

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Tricuspid valve abnormalities detected in fetal life include Ebstein anomaly and tricuspid valve dysplasia. The differentiation between these 2 entities can sometimes be challenging in the 2nd trimester fetus. We report a case of tricuspid valve dysplasia diagnosed on fetal autopsy.

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Purpose: Extracellular accumulation of all-trans-retinaldehyde (atRAL), a highly reactive visual cycle intermediate, is toxic to cells of the outer retina and contributes to retinal and macular degenerations. However, the contribution of atRAL to retinal capillary function has not been studied. We hypothesized that atRAL released from the outer retina can contribute to retinal vascular permeability.

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The tricomponent composite chitosan/polyvinyl pyrrolidone (CS/PVP) with different weight ratios of (0, 20, 40, 60, and 80 wt%) of copper-hydroxyapatite (Cu-HAP) were prepared by solvent casting technique, which was characterized by X-ray diffraction, Fourier-transform infrared, and scanning electron microscopy with energy-dispersive X-ray to confirm the formation of Cu-HAP/CS/PVP composite. The Cu-HAP/CS/PVP composite with 80 wt% Cu-HAP showed 98.73 ± 1.

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Zn-Mn HAP (Zinc and Manganese substituted Hydroxyapatite), CMC (Carboxymethyl cellulose)/PVP (Polyvinyl pyrrolidone) and (Zn-Mn HAP)/CMC/PVP (Zn = Mn = 0.05, 0.1 M) were prepared by hydrothermal and electrospinning methods respectively.

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A rapid synthetic technique is investigated for magnetic nanoparticles (CoCuFeCeO (x = 0, y = 0), (x = 0.05, y = 0), (x = 0, y = 0.5), and (x = 0.

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Article Synopsis
  • - Diabetic complications such as diabetic peripheral neuropathy (DPN), diabetic kidney disease (DKD), and diabetic retinopathy (DR) are on the rise and greatly impact patients' health, yet current treatments are largely ineffective.
  • - New research on BKS-db/db mice reveals distinct mitochondrial responses in nerve, kidney, and retinal tissues linked to type 2 diabetes (T2D), but it's uncertain if these changes cause tissue damage or are a result of it.
  • - Treatment with the mitochondrial uncoupler niclosamide ethanolamine (NEN) showed minimal effects on the progression of T2D and its complications, suggesting that a broad approach to targeting mitochondria may not benefit patients and underscoring the
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Purpose: Retinal detachment (RD) separates the retina from the underlying retinal pigment epithelium, resulting in a gradual degeneration of photoreceptor (PR) cells. It is known that RD also results in an inflammatory response, but its contribution to PR degeneration is unknown. In this study we examine the inflammatory responses to RD in patient vitreous and validate a mouse experimental RD as a model of this phenomenon.

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A series of alkoxy-substituted 2H-chromenes were synthesized by a one-pot three-component reaction using salicylaldehydes, acetyl acetone and alcohol as reactant and medium with tetra-n-butylammonium fluoride (TBAF) as catalyst. Simple reaction conditions, short reaction time and overall good yield of products make this synthetic strategy an efficient one to synthesize 2H-chromene molecules. All the synthesized compounds were evaluated for antioxidant activities.

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Introduction: The knowledge of detailed calyceal anatomy is essential for performing urologic procedures such as percutaneous nephrolithotomy, percutaneous nephrostomy, flexible ureterorenoscopy, endopyelotomy, and retrograde renal surgery. This study was performed to analyze the various patterns of pelvicalyceal system in the South Indian population, and compare these with previously published studies in different populations.

Methods: The study was conducted in 100 kidney specimens.

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Unlabelled: In this study, the role of CX3CR1 in the progression of diabetic retinopathy (DR) was investigated. The retinas of wild-type (WT), CX3CR1 null (CX3CR1, KO), and heterozygous (CX3CR1, Het) mice were compared in the presence and absence of streptozotocin (STZ)-induced diabetes. CX3CR1 deficiency in STZ-KO increased vascular pathology at 4 months of diabetes, as a significant increase in acellular capillaries was observed only in the STZ-KO group.

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Insulin-like growth factor 1 (IGF-1) can provide long-term neurotrophic support by activation of Akt, inhibition of FoxO nuclear localization and suppression of Bim gene transcription in multiple neuronal systems. However, MEK/ERK activation can also promote neuron survival through phosphorylation of BimEL. We explored the contribution of the PI3K/Akt/FoxO and MEK/ERK/BimEL pathways in IGF-1 stimulated survival after serum deprivation (SD) of R28 cells differentiated to model retinal neurons.

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Retinal ischemia-reperfusion (IR) induces neurodegenaration as well as blood-retinal barrier (BRB) breakdown causing vascular permeability. Whereas the neuronal death has been extensively studied, the molecular mechanisms related to BRB breakdown in IR injury remain poorly understood. In this study, we investigated the early changes in tight junctional (TJ) proteins in response to IR injury.

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Background: Many retinal diseases are associated with vascular dysfunction accompanied by neuroinflammation. We examined the ability of minocycline (Mino), a tetracycline derivative with anti-inflammatory and neuroprotective properties, to prevent vascular permeability and inflammation following retinal ischemia-reperfusion (IR) injury, a model of retinal neurodegeneration with breakdown of the blood-retinal barrier (BRB).

Methods: Male Sprague-Dawley rats were subjected to 45 min of pressure-induced retinal ischemia, with the contralateral eye serving as control.

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