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1.
Diagnostics (Basel) ; 14(15)2024 Jul 26.
Article in English | MEDLINE | ID: mdl-39125491

ABSTRACT

Impaired retinal blood flow is associated with ocular diseases such as glaucoma, macular degeneration, and diabetic retinopathy. Among several ocular imaging techniques developed to measure retinal blood flow both invasively and non-invasively, adaptive optics (AO)-enabled scanning laser ophthalmoscopy (AO-SLO) resolves individual red blood cells and provides a high resolution with which to measure flow across retinal microvasculature. However, cross-validation of flow measures remains a challenge owing to instrument and patient-specific variability in each imaging technique. Hence, there is a critical need for a well-controlled clinical flow phantom for standardization and to establish blood-flow measures as clinical biomarkers for early diagnosis. Here, we present the design and validation of a simple, compact, portable, linear flow phantom based on a direct current motor and a conveyor-belt system that provides linear velocity tuning within the retinal microvasculature range (0.5-7 mm/s). The model was evaluated using a sensitive AO-SLO line-scan technique, which showed a <6% standard deviation from the true velocity. Further, a clinical SLO instrument showed a linear correlation with the phantom's true velocity (r2 > 0.997). This model has great potential to calibrate, evaluate, and improve the accuracy of existing clinical imaging systems for retinal blood flow and aid in the diagnosis of ocular diseases with abnormal blood flow.

2.
Diagnostics (Basel) ; 14(14)2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39061655

ABSTRACT

Photoreceptors (PRs) and retinal pigment epithelial (RPE) cells form a functional unit called the PR-RPE complex. The PR-RPE complex plays a critical role in maintaining retinal homeostasis and function, and the quantification of its structure and topographical arrangement across the macula are important for understanding the etiology, mechanisms, and progression of many retinal diseases. However, the three-dimensional cellular morphology of the PR-RPE complex in living human eyes has not been completely described due to limitations in imaging techniques. We used the cellular resolution and depth-sectioning capabilities of a custom, high-speed Fourier domain mode-locked laser-based adaptive optics-optical coherence tomography (FDML-AO-OCT) platform to characterize human PR-RPE complex topography across the temporal macula from eleven healthy volunteers. With the aid of a deep learning algorithm, key metrics were extracted from the PR-RPE complex of averaged AO-OCT volumes including PR and RPE cell density, PR outer segment length (OSL), and PR/RPE ratio. We found a tight grouping among our cohort for PR density, with a mean (±SD) value of 53,329 (±8106) cells/mm2 at 1° decreasing to 8669 (±737) cells/mm2 at 12°. We observed a power function relationship between eccentricity and both PR density and PR/RPE ratio. We found similar variability in our RPE density measures, with a mean value of 7335 (±681) cells/mm2 at 1° decreasing to 5547 (±356) cells/mm2 at 12°, exhibiting a linear relationship with a negative slope of -123 cells/mm2 per degree. OSL monotonically decreased from 33.3 (±2.4) µm at 1° to 18.0 (±1.8) µm at 12°, following a second-order polynomial relationship. PR/RPE ratio decreased from 7.3 (±0.9) µm at 1° to 1.5 (±0.1) µm at 12°. The normative data from this investigation will help lay a foundation for future studies of retinal pathology.

3.
ACS Appl Mater Interfaces ; 16(14): 17797-17811, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38552198

ABSTRACT

The design and exploration of advanced materials as a durable multifunctional electrocatalyst toward sustainable energy generation and storage development is the most perdurable challenge in the domain of renewable energy research. Herein, a facile in situ solvothermal approach has been adopted to prepare a methylviologen-regulated crystalline metal phosphonate compound, [C12H14N2][Ni(C11H11N2)(H2hedp)2]2•6H2O (NIT1), (H4hedp = 1-hydroxyethane 1,1-diphosphonic acid) and well characterized by several techniques. The as-prepared NIT1 displays excellent bifunctional electrocatalytic activity with dynamic stability toward oxygen evolution reaction (η10 = 288 mV) and hydrogen evolution reaction (η10 = 228 mV) in alkaline (1.0 M KOH) and acidic mediums (0.5 M H2SO4), respectively. Such a low overpotential and Tafel slope (68 mV/dec for OER; 56 mV/dec for HER) along with long-term durability up to 20 h of NIT1 make it superior to benchmark the electrocatalyst and various nonprecious metal-based catalysts under similar experimental condition. Further, the electrochemical supercapacitor measurements (in three-electrode system) reveal that the NIT1 electrode possesses much higher specific capacity of 187.6 C g-1 at a current density of 2 A g-1 (272 C g-1 at 5 mV s-1) with capacitance retention of 75.2% over 10,000 cycles at 14 A g-1 (Coulombic efficiency > 99%) in 6 M KOH electrolyte medium. Finally for a practical application, an asymmetric supercapacitor device (coin cell) is assembled by NIT1 material. The as-fabricated device delivers the maximum energy density of 39.4 Wh kg-1 at a power density of 450 W kg-1 and achieves a wide voltage window of 1.80 V. Notably, the device endures a remarkable cycle performance with cyclic retention of 92% (Coulombic efficiency > 99%) even after 14,000 charge/discharge cycles at 10 A g-1. Nevertheless, the extraordinary electrochemical activities toward OER and HER as well as the high-performance device fabrication for LED illumination of such a noble metal-free lower-dimensional charge-transfer compound are truly path breaking and would be promising for the development of advanced multifunctional materials.

4.
Article in English | MEDLINE | ID: mdl-38083896

ABSTRACT

The pharmacological treatments that are now recommended for the therapy of chronic illnesses are examined in a great number of studies to determine whether or not they are both safe and effective. Therefore, it is important to investigate various alternative therapeutic assistance, such as natural remedies derived from medicinal plants. In this context, chicoric acid, classified as a hydroxycinnamic acid, has been documented to exhibit a range of health advantages. These include antiviral, antioxidant, anti-inflammatory, obesity-preventing, and neuroprotective effects. Due to its considerable pharmacological properties, chicoric acid has found extensive applications in food, pharmaceuticals, animal husbandry, and various other commercial sectors. This article provides a comprehensive overview of in vitro and in vivo investigations on chicoric acid, highlighting its beneficial effects and therapeutic activity when used as a preventative and management aid for public health conditions, including diabetes, cardiovascular disease, and hepatic illnesses like non-alcoholic steatohepatitis. Moreover, further investigation of this compound can lead to its development as a potential phytopharmaceutical candidate.

5.
Article in English | MEDLINE | ID: mdl-37670710

ABSTRACT

Parkinson's disease (PD) is a widespread neurodegenerative disorder that exerts a broad variety of detrimental effects on people's health. Accumulating evidence suggests that mitochondrial dysfunction, neuroinflammation, α-synuclein aggregation and autophagy dysfunction may all play a role in the development of PD. However, the molecular mechanisms behind these pathophysiological processes remain unknown. Currently, research in PD has focussed on high mobility group box 1 (HMGB1), and different laboratory approaches have shown promising outcomes to some level for blocking HMGB1. Given that HMGB1 regulates mitochondrial dysfunction, participates in neuroinflammation, and modulates autophagy and apoptosis, it is hypothesised that HMGB1 has significance in the onset of PD. In the current review, research targeting multiple roles of HMGB1 in PD pathology was integrated, and the issues that need future attention for targeted therapeutic approaches are mentioned.

6.
Article in English | MEDLINE | ID: mdl-37550917

ABSTRACT

Rheumatoid arthritis (RA) is a systemic, inflammatory disease that affects joints and leads to progressive cartilage and bone deterioration. The susceptibility to RA is determined by genetic and environmental factors. Recently, many efforts have been undertaken to develop natural compounds capable of reducing the symptoms of RA to avoid the negative effects of the current anti-inflammatory drugs. Interestingly, substantial data has revealed that nutritional, and herbal supplements may be effective adjuvants in reducing the symptoms of RA by influencing the pathogenic inflammatory processes. In this context, various kinds of food, phenolic substances, spices like ginger, and turmeric, several vitamins, and probiotics are reported to control the activity of inflammatory molecules implicated in the pathophysiology of RA and therefore, have proved successful in slowing the course of this arthritic illness. Therefore, the goal of this review article is to compile various findings on RA that have revealed illuminating information about the antiinflammatory, antioxidant, analgesic, immunomodulatory, and bone erosion-preventing properties of nutritional, and herbal components. Conclusively, this review concentrates on natural ingredients that may enhance overall well-being, promote health, and lessen the risk of RA.

7.
Heliyon ; 9(6): e16531, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37274679

ABSTRACT

Additive manufacturing technology and its benefits have a significant impact on different industrial applications. The 3D printing technologies help manufacture lightweight intricate geometrical designs with enhanced strengths. The present study investigates the blended effects of previously recommended parameters of different infill patterns (line, triangle, and concentric) and infill densities (75, 80, and 85%) with varying thicknesses of layers (100, 200, and 300 µm). The test samples were created through Fused Filament Fabrication (FFF) technology using Acrylonitrile Butadiene Styrene (ABS) 3D printing. Mechanical properties were evaluated through tensile and impact strength tests conducted in accordance with ASTM standards. The experimental investigation reveals that the infill pattern greatly affected both tensile and impact strength. The best results were obtained with a concentric infill pattern, along with 80% infill density and 100 µm layer thickness. These conditions resulted in 123% and 115% higher tensile strength and 168% and 80% higher impact strength compared to line and triangle patterns, respectively.

8.
Curr Mol Med ; 2023 May 09.
Article in English | MEDLINE | ID: mdl-37165502

ABSTRACT

Neurodegenerative disorders are among the most common life-threatening disorders among the elderly worldwide and are marked by neuronal death in the brain and spinal cord. Several studies have demonstrated the beneficial role of dietary fatty acids in different brain disorders. This is due to their neurotrophic, antioxidant, and anti-inflammatory properties. Furthermore, extensive evidence shows that an unbalanced intake of certain dietary fatty acids increases the risk of neuropsychiatric diseases. Several research has been done on erucic acid, an ingestible omega-9 fatty acid that is found in Lorenzo's oil. Erucic acid was previously thought to be a natural toxin because of its negative effects on heart muscle function and hepatic steatosis, but it has been discovered that erucic acid is regularly consumed in Asian countries through the consumption of cruciferous vegetables like mustard and rapeseed oil with no evidence of cardiac harm. Erucic acid can also be transformed into nervonic acid, a crucial element of myelin. Therefore, erucic acid may have remyelinating effects, which may be crucial for treating different demyelinating conditions. Also, erucic acid exerts antioxidant and anti-inflammatory effects, suggesting its possible therapeutic role in different neurodegenerative disorders. Considering the fruitful effects of this compound, this article reviews the probable role of erucic acid as a pharmacological agent for treating and managing different neurodegenerative disorders.

9.
J Biomed Mater Res A ; 111(8): 1279-1291, 2023 08.
Article in English | MEDLINE | ID: mdl-36916776

ABSTRACT

In the field of tissue engineering, 3D scaffolds and cells are often combined to yield constructs that are used as therapeutics to repair or restore tissue function in patients. Viable cells are often required to achieve the intended mechanism of action for the therapy, where the live cells may build new tissue or may release factors that induce tissue regeneration. Thus, there is a need to reliably measure cell viability in 3D scaffolds as a quality attribute of a tissue-engineered medical product. Here, we developed a noninvasive, label-free, 3D optical coherence tomography (OCT) method to rapidly (2.5 min) image large sample volumes (1 mm3 ) to assess cell viability and distribution within scaffolds. OCT imaging was assessed using a model scaffold-cell system consisting of a polysaccharide-based hydrogel seeded with human Jurkat cells. Four test systems were used: hydrogel seeded with live cells, hydrogel seeded with heat-shocked or fixed dead cells and hydrogel without any cells. Time series OCT images demonstrated changes in the time-dependent speckle patterns due to refractive index (RI) variations within live cells that were not observed for pure hydrogel samples or hydrogels with dead cells. The changes in speckle patterns were used to generate live-cell contrast by image subtraction. In this way, objects with large changes in RI were binned as live cells. Using this approach, on average, OCT imaging measurements counted 326 ± 52 live cells per 0.288 mm3 for hydrogels that were seeded with 288 live cells (as determined by the acridine orange-propidium iodide cell counting method prior to seeding cells in gels). Considering the substantial uncertainties in fabricating the scaffold-cell constructs, such as the error from pipetting and counting cells, a 13% difference in the live-cell count is reasonable. Additionally, the 3D distribution of live cells was mapped within a hydrogel scaffold to assess the uniformity of their distribution across the volume. Our results demonstrate a real-time, noninvasive method to rapidly assess the spatial distribution of live cells within a 3D scaffold that could be useful for assessing tissue-engineered medical products.


Subject(s)
Tissue Engineering , Tomography, Optical Coherence , Humans , Tissue Engineering/methods , Cell Survival , Tissue Scaffolds , Hydrogels/pharmacology
10.
Chem Biol Drug Des ; 101(6): 1229-1240, 2023 06.
Article in English | MEDLINE | ID: mdl-36752710

ABSTRACT

Parkinson's disease is among the most common forms of neurodegenerative illness, with present treatment being primarily symptomatic and frequently coming with substantial adverse effects. Neuronal degeneration may arise due to a variety of pathological events, like inflammatory responses, neurotransmitter dysregulation, oxidative damage, mitochondrial malfunction, apoptosis, and genetic factors. The health issue and financial burden brought on by Parkinson's disease can worsen as the population ages. In the search for new and secure therapeutic agents for Parkinson's disease, several natural compounds have been shown to exert considerable neuroprotective benefits. Crocin, a naturally occurring carotenoid molecule, was found to have neuroprotective potential in the therapy of this disorder. Taking into account, the outcomes of various studies and the restorative actions of crocin, the present study emphasized the protective ability of crocin in this disease. Given the strong evidence supporting the neuroprotective ability of crocin, it is inferred that crocin inhibits inflammatory, apoptotic, and antioxidant processes through multiple mechanisms. Therefore, this compound is considered a safe and effective therapeutic choice for neurodegenerative illnesses like Parkinson's disease. However, more research on its efficacy as a treatment of Parkinson's disease is needed, specifically examining its mechanisms and the results obtained in clinical trials.


Subject(s)
Neuroprotective Agents , Parkinson Disease , Humans , Parkinson Disease/drug therapy , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Carotenoids/pharmacology , Carotenoids/therapeutic use , Antioxidants/pharmacology , Antioxidants/therapeutic use , Oxidative Stress
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