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1.
PLoS One ; 19(5): e0300645, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38753855

RESUMO

For a car that is propelled by an armature-controlled DC motor This study proposes an adjustable linear positioning control. In this paper, to optimize the parameters of the car's position controller the sine cosine optimization algorithm (SCA) is utilized, with support from the Balloon effect (BE), The BE is incorporated to enhance the responsiveness of the traditional sine cosine optimization algorithm when faced with external disturbances and variations in system parameters. In the proposed approach, the determined value of the open loop transfer function of the motor and the updated values of the controller gains serve as the basis for the modified sine cosine algorithm's objective function (OF). Under the influence of changes in motor parameters and step load disturbances, the system using the suggested controller is evaluated. Results from simulations and experiments show that the proposed adaptive controller, which implements the modified sine cosine algorithm, enhances the system's overall performance in the presence of load disturbances and parameter uncertainties.


Assuntos
Algoritmos , Humanos , Simulação por Computador , Desenho de Equipamento
3.
Toxicol Res (Camb) ; 13(2): tfae054, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38617712

RESUMO

Alzheimer's disease (ad) is a neurological condition that worsens over time and is characterized by the buildup of amyloid (Aß) plaques in the brain parenchyma. Neuroprotection and cholinesterase inhibition have been the two primary techniques used in the creation of medications to date. In ad, a novel sort of programmed cell death known as ferroptosis takes place along with iron buildup, lipid peroxidation, and glutathione deficiency. The objective of the current investigation was to examine the neuroprotective and anti-ferroptotic role of nanocurcumin and Donepezil against model of aluminum chloride AlCl3 and D-galactose induced ad. The experiment was performed on 70 rats divided into (G1: control, G2: NCMN, G3: Donepezil, G4: ad-model, G5: Donepezil co-treatment, G6: NCMN co-treatment and G7: NCMN+Donepezil co-treatment). Hematological parameters and biochemical investigations as oxidative stress, liver function, kidney function, iron profile and plasma fibrinogen were evaluated. Treatment with Nanocurcumin alone or in combination with Donepezil improved oxidative stress, liver functions, and kidney functions, improve iron profile and decreased plasma fibrinogen.

4.
Sci Rep ; 14(1): 7912, 2024 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575715

RESUMO

Recent advancements in the field of biomedical engineering have underscored the pivotal role of biodegradable materials in addressing the challenges associated with tissue regeneration therapies. The spectrum of biodegradable materials presently encompasses ceramics, polymers, metals, and composites, each offering distinct advantages for the replacement or repair of compromised human tissues. Despite their utility, these biomaterials are not devoid of limitations, with issues such as suboptimal tissue integration, potential cytotoxicity, and mechanical mismatch (stress shielding) emerging as significant concerns. To mitigate these drawbacks, our research collective has embarked on the development of protein-based composite materials, showcasing enhanced biodegradability and biocompatibility. This study is dedicated to the elaboration and characterization of an innovative suture fabricated from human serum albumin through an extrusion methodology. Employing a suite of analytical techniques-namely tensile testing, scanning electron microscopy (SEM), and thermal gravimetric analysis (TGA)-we endeavored to elucidate the physicochemical attributes of the engineered suture. Additionally, the investigation extends to assessing the influence of integrating biodegradable organic modifiers on the suture's mechanical performance. Preliminary tensile testing has delineated the mechanical profile of the Filament Suture (FS), delineating tensile strengths spanning 1.3 to 9.616 MPa and elongation at break percentages ranging from 11.5 to 146.64%. These findings illuminate the mechanical versatility of the suture, hinting at its applicability across a broad spectrum of medical interventions. Subsequent analyses via SEM and TGA are anticipated to further delineate the suture's morphological features and thermal resilience, thereby enriching our comprehension of its overall performance characteristics. Moreover, the investigation delves into the ramifications of incorporating biodegradable organic constituents on the suture's mechanical integrity. Collectively, the study not only sheds light on the mechanical and thermal dynamics of a novel suture material derived from human serum albumin but also explores the prospective enhancements afforded by the amalgamation of biodegradable organic compounds, thereby broadening the horizon for future biomedical applications.


Assuntos
Materiais Biocompatíveis , Engenharia Tecidual , Humanos , Estudos Prospectivos , Materiais Biocompatíveis/química , Suturas , Albuminas , Albumina Sérica Humana
5.
Int J Biol Macromol ; 268(Pt 2): 131737, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38657940

RESUMO

Recently, there has been a surge in curiosity regarding the application of biopolymer-derived nanomaterials, primarily attributable to their extensive array of potential applications. In this study, nanocellulose was extracted from algae, biomolecule substances synthesized selenium nanoparticles, and a simple nanocomposite of nanocellulose and nanoselenium was elaborated using nanocellulose as a reducing agent under hydrothermal conditions. These nanocomposite materials have markedly improved properties at low concentrations. Our obtained polymers were characterized using techniques including Fourier-transform infrared spectroscopy, X-ray powder diffraction, Thermo gravimetric analysis (TGA), Scanning electron microscopic (SEM), Energy Dispersive X-ray analysis (EDX), Transmission electron microscopic (TEM), Zeta Potential and Dynamic Light Scattering (DLS). The size of nanocellulose, nanoselenium, and nanocomposite ranged from 35 to 85 nm. Antimicrobial investigation of the prepared nanopolymers was tested against Gram-negative bacteria such as Bacillus subtilis ATCC 6633 and Staphylococcus aureus ATCC 6538, Gram-positive bacteria such as Escherichia coli ATCC8739 and Pseudomonas aeruginosa ATCC 90274 and fungi such as Candida albicans ATCC 10221 besides Aspergillus fumigatus. In antibacterial action tests, nanoselenium showed significant efficacy against Bacillus subtilis with a 12 mm zone of inhibition, while the nanocomposite eclipsed all microorganisms. Nanocellulose and the nanocomposite were potent against Staphylococcus aureus (14 mm and 16 mm zones of inhibition, respectively). The nanocomposite showed potential against Escherichia coli and Pseudomonas aeruginosa (17 mm and 15 mm zones of inhibition, respectively). All polymers effectively inhibited Candida albicans growth (18 mm for the nanocomposite). The minimum inhibitory concentrations (MIC) for three polymers have also been established. While nanocellulose displayed a MIC of 62.5 µg/ml in contradiction to Staphylococcus aureus, nanoselenium demonstrated a significant MIC of 3.95 µg/ml against Bacillus subtilis. These findings highlight the potential of the nanocomposite (nanocellulose-nanoselenium) as a broad-spectrum antimicrobial polymer.

6.
Pediatr Dev Pathol ; : 10935266241230600, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38468555

RESUMO

We present 2 diagnostically challenging cases of pediatric/adolescent relapsed/refractory aggressive mature B-cell non-Hodgkin lymphoma (B-NHL) within the spectrum of Burkitt lymphoma and diffuse large B-cell lymphoma and illustrate the different therapeutic regimens that are employed for pediatric and adult cancer centers. Both cases displayed varying-sized lymphoma cells with occasional single prominent nucleoli and heterogeneous BCL2 expression. Cytogenetics revealed complex karyotypes with t(8:14)(q24.2;q32) and IGH::MYC rearrangement by FISH. Next generation sequencing revealed deleterious TP53 and MYC mutations. We concluded that both could be diagnosed as "DLBCL-NOS with MYC rearrangement" using the current pathologic classifications, 2022 International Consensus Classification (ICC) and World Health Organization Classifications of Haematolymphoid Tumors (WHO-HAEM5). This report illustrates diagnostic challenges and treatment dilemmas that may be encountered, particularly for adolescent and young adults (AYA).

7.
Arab J Gastroenterol ; 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38378355

RESUMO

BACKGROUND AND STUDY AIMS: Liver dysfunction is a common manifestation of the COVID-19 infection. We aimed to study transaminase abnormalities through different waves of COVID-19 and their relations to disease severity or mortality. PATIENTS AND METHODS: A retrospective study included 521 Egyptian patients diagnosed with COVID-19. Data was retrieved from the medical records of patients who were admitted from April 2020 to October 2021 in Kasr Al-Ainy Hospitals, Cairo University, with categorization according to disease severity in correspondence to the four waves. RESULTS: The median age was lower in the first wave compared to other waves, with male predominance across all waves. The most commonly encountered comorbidity overall was hypertension, followed by diabetes mellitus. White blood cells, ferritin, and interleukin-6 showed the highest median values in the second wave, with significantly higher median C-reactive protein on day 1 in the first wave. Forty percent of the patients showed elevated hepatic transaminases on admission in four waves, with no statistically significant difference between waves. On day 5, around half of the patients had elevated transaminases, with no significant difference between waves. Most CT findings were of moderate severity. Clinical severity was higher in the second wave. It was observed that the higher the disease severity, the greater the proportion of patients with elevated hepatic transaminases. The mortality rate was markedly high in cases who had elevated ALT or AST on day 5. The association between elevated enzymes on admission and mortality was seen in the first wave only, with a fatality rate of 22.5% in cases with increased baseline ALT and AST versus 5% in those with normal baseline enzymes. CONCLUSION: There was no significant difference in transaminases between the four waves. Elevated transaminases were positively associated with increased mortality and severity, reflecting their prognostic value.

8.
Tissue Cell ; 87: 102332, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367325

RESUMO

Protection from liver damage and the repercussion of that harm is thought to be crucial for reducing the number of deaths each year. This work was developed to evaluate the possible role of silver nanocomposite prepared using Nigella sativa (N. sativa) aqueous extract against the hepatic damage brought on by thioacetamide (TAA), with particular attention to how they affect the NF-κß, TNF-α, IL-1ß, and COX-2 signaling pathways. There were seven groups of male Wistar rats used as follows: control, saline, N. sativa aqueous extract (NSAE; 200 mg/kg/d), N. sativa silver nanocomposite (NS-AgNC; 0.25 mg/kg/d), TAA (100 mg/kg; thrice weekly), NSAE + TTA, and NS-AgNC + TAA, respectively. The experiment continued for six weeks. The results showed that NS-AgNPs significantly enhanced liver functions (p<0.05) (albumin, ALP, LDH, AST, total protein, ALT, and globulin) and oxidant/antioxidant biomarkers (p<0.05) (H2O2, MDA, PCC, NO, SOD, CAT, GPx, GR, GST and, GSH), contrasted with TAA group. Moreover, a significant (p<0.05) downregulation of the gene expressions (COX-2, TNF-α, IL-1ß, and NF-κß) was also achieved by using silver nanocomposite therapy. These findings have been supported by histological analysis. Collectively, NS-AgNC exhibits more prominent and well-recognized protective impacts than NSAE in modulating the anti-inflammatory, genotoxicity and oxidative stress effects against TAA-induced liver injuries.


Assuntos
Hepatopatias , Nigella sativa , Masculino , Ratos , Animais , Tioacetamida/toxicidade , Nigella sativa/metabolismo , Prata/toxicidade , Prata/metabolismo , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo , Ciclo-Oxigenase 2 , Peróxido de Hidrogênio/metabolismo , Antioxidantes/metabolismo , Estresse Oxidativo , Fígado/patologia , Hepatopatias/patologia , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo
9.
Int J Biol Macromol ; 263(Pt 2): 130387, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38401586

RESUMO

Alzheimer's disease (AD) is a prevalent form of neurodegenerative disease with a complex pathophysiology that remains not fully understood, and the exact mechanism of neurodegeneration is uncertain. Ferroptosis has been linked to the progression of degenerative diseases observed in AD models. The present study is designed to investigate the protective effects of spermidine, a potent antioxidant and iron chelator, and its synergistic interactions with ciprofloxacin, another iron chelator, in modulating ferroptosis and mitigating AD progression in rats. This study investigated AD-related biomarkers like neurotoxic amyloid beta (Aß), arginase I, and serotonin. Spermidine demonstrated an anti-ferroptotic effect in the AD model, evident from the modulation of ferroptosis parameters such as hippocampus iron levels, reduced protein expression of transferrin receptor 1 (TFR1), and arachidonate 15-lipoxygenase (ALOX15). Additionally, the administration of spermidine led to a significant increase in protein expression of phosphorylated nuclear factor erythroid 2-related factor 2 (p-Nrf2) and upregulation of Cystine/glutamate transporter (SLC7A11) gene expression. Moreover, spermidine notably decreased p53 protein levels, acrolein, and gene expression of spermidine/spermine N1-acetyltransferase 1 (SAT1). Overall, our findings suggest that spermidine and/or ciprofloxacin may offer potential benefits against AD by modulating ferroptosis. Furthermore, spermidine enhanced the antioxidant efficacy of ciprofloxacin and reduced its toxic effects.


Assuntos
Doença de Alzheimer , Ferroptose , Doenças Neurodegenerativas , Ratos , Masculino , Animais , Doença de Alzheimer/tratamento farmacológico , Espermidina/farmacologia , Espermidina/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Peptídeos beta-Amiloides/metabolismo , Estresse Oxidativo , Ciprofloxacina/farmacologia , Quelantes de Ferro/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo
10.
Sci Rep ; 14(1): 2838, 2024 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310142

RESUMO

In this work, the effect of adding Magnesium Oxide (MgO) and Titanium Dioxide (TiO2) nanoparticles to enhance the properties of the bone cement used for hip prosthesis fixation. Related to previous work on enhanced bone cement properties utilizing MgO and TiO2, samples of composite bone cement were made using three different ratios (0.5%:1%, 1.5%:1.5%, and 1%:0.5%) w/w of MgO and TiO2 to determine the optimal enhancement ratio. Hardness, compression, and bending tests were calculated to check the mechanical properties of pure and composite bone cement. The surface structure was studied using Fourier transform infrared spectroscopy (FTIR) and Field emission scanning electron microscopy (FE-SEM). Setting temperature, porosity, and degradation were calculated for each specimen ratio to check values matched with the standard range of bone cement. The results demonstrate a slight decrease in porosity up to 2.2% and degradation up to 0.17% with NP-containing composites, as well as acceptable variations in FTIR and setting temperature. The compression strength increased by 2.8% and hardness strength increased by 1.89% on adding 0.5%w/w of MgO and 1.5%w/w TiO2 NPs. Bending strength increases by 0.35% on adding 1.5% w/w of MgO and 0.5% w/w TiO2 NPs, however, SEM scan shows remarkable improvement for surface structure.


Assuntos
Óxido de Magnésio , Nanopartículas , Cimentos Ósseos , Titânio/química , Nanopartículas/química , Articulação do Quadril , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Cell Mol Biol Lett ; 29(1): 14, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38225555

RESUMO

Rheumatoid arthritis (RA) is an autoimmune disease involving T and B lymphocytes. Autoantibodies contribute to joint deterioration and worsening symptoms. Adenosine deaminase (ADA), an enzyme in purine metabolism, influences adenosine levels and joint inflammation. Inhibiting ADA could impact RA progression. Intracellular ATP breakdown generates adenosine, which increases in hypoxic and inflammatory conditions. Lymphocytes with ADA play a role in RA. Inhibiting lymphocytic ADA activity has an immune-regulatory effect. Synovial fluid levels of ADA are closely associated with the disease's systemic activity, making it a useful parameter for evaluating joint inflammation. Flavonoids, such as quercetin (QUE), are natural substances that can inhibit ADA activity. QUE demonstrates immune-regulatory effects and restores T-cell homeostasis, making it a promising candidate for RA therapy. In this review, we will explore the impact of QUE in suppressing ADA and reducing produced the inflammation in RA, including preclinical investigations and clinical trials.


Assuntos
Inibidores de Adenosina Desaminase , Artrite Reumatoide , Quercetina , Humanos , Adenosina , Adenosina Desaminase/metabolismo , Artrite Reumatoide/tratamento farmacológico , Inflamação/tratamento farmacológico , Quercetina/farmacologia , Inibidores de Adenosina Desaminase/farmacologia
12.
Arab J Urol ; 22(1): 6-12, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38205383

RESUMO

Background: Erectile dysfunction (ED) is a prevalent complication observed in male patients with liver cirrhosis; however, there is limited understanding of the etiological determinants responsible for its occurrence. The objective of this investigation is to explore potential contributory factors that underlie the development of ED in male patients with liver cirrhosis. Method: A cross-sectional study was conducted on 200 male patients with liver cirrhosis, who were divided into three groups according to the Child score. ED was studied using the International Index of Erectile Function (IIEF-5) Questionnaire and penile Doppler. Results: The prevalence of ED among the cirrhotic patients was 80%, and it was more frequent in patients with advanced liver disease (Child C). Penile venous leakage was observed in 20% of cirrhotic patients, which increased to 28.6% in those with advanced liver cirrhosis. Multivariate logistic regression analysis showed that age, low albumin levels, elevated INR, high hemoglobin levels, and Child C were predictors of ED in cirrhotic patients. Conclusion: Several clinical variables have been identified as potential contributors to the development of erectile dysfunction (ED) in patients with cirrhosis. These variables include advanced age, decreased levels of albumin, elevated INR, increased hemoglobin levels, and Child C classification. Early identification and treatment of these factors could potentially improve the quality of life for cirrhotic patients with ED. Notably, patients with ED in this population were observed to have elevated levels of INR, serum bilirubin, and hemoglobin, as well as reduced levels of serum albumin.

13.
J Neuroendocrinol ; 36(1): e13356, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37985011

RESUMO

Besides COVID-19, two of the most critical outbreaks of our day are insulin resistance, type 2 diabetes mellitus (T2DM), and Alzheimer's disease (AD). Each disease's pathophysiology is well established. Furthermore, a substantial overlap between them has coexisted. Uncertainty remains on whether T2DM and AD are parallel illnesses with the same origin or separate illnesses linked through violent pathways. The current study was aimed at testing whether the insulin resistance in the brain results in AD symptoms or not. Insulin resistance was induced in the brains of rats using a single intracerebroventricular streptozotocin (STZ) dose. We then measured glucose, insulin receptor substrate 2 (IRS-2), amyloid ß (Aß) deposition, and tau phosphorylation in the brain to look for signs of insulin resistance and AD. The results of this study indicated that a single dose of STZ was able to induce insulin resistance in the brain and significantly decline IRS-2. This resistance was accompanied by obvious memory loss, Aß deposition, and tau phosphorylation, further visible diminishing in neurotransmitters such as dopamine and acetylcholine. Furthermore, oxidative stress was increased due to the antioxidant system being compromised. Interestingly, the pancreas injury and peripheral insulin resistance coexisted with brain insulin resistance. Indeed, the antidiabetic metformin was able to enhance all these drastic effects. In conclusion, brain insulin resistance could lead to AD and vice versa. These are highly linked syndromes that could influence peripheral organs. Further studies are required to stabilize this putative pathobiology relationship between them.


Assuntos
Doença de Alzheimer , Diabetes Mellitus Tipo 2 , Resistência à Insulina , Metformina , Ratos , Animais , Doença de Alzheimer/metabolismo , Resistência à Insulina/fisiologia , Peptídeos beta-Amiloides/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Metformina/farmacologia , Metformina/metabolismo , Insulina/metabolismo , Encéfalo/metabolismo , Modelos Animais de Doenças
14.
Prostaglandins Other Lipid Mediat ; 170: 106791, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37918555

RESUMO

Alzheimer's disease (AD) hallmarks include amyloid-ßeta (Aß) and tau proteins aggregates, neurite degeneration, microglial activation with cognitive impairment. Phosphatidylinositol-3-kinase/protein kinase B/Glycogen synthase kinase-3-beta (PI3K/AKT/GSK-3) pathway is essential for neuroprotection, cell survival and proliferation by blocking apoptosis. This study aimed to assess protective role of nanocurcumin (NCMN) as strong antioxidant and anti-inflammatory agent with elucidating its synergistic effects with Donepezil as acetylcholinesterase inhibitor on AD in rats via modulating PI3K/AKT/GSK-3ß pathway. The experiment was performed on 70 male Wistar albino rats divided into seven groups (control, NCMN, Donepezil, AD-model, Donepezil co-treatment, NCMN only co-treatment, and NCMN+Donepezil combined treatment). Behavioral and biochemical investigations as cholinesterase activity, oxidative stress (malondialdehyde, reduced glutathione, nitric oxide, superoxidedismutase, and catalase), tumor necrosis factor-alpha, Tau, ß-site amyloid precursor protein cleaving enzyme-1 (BACE-1), Phosphatase and tensin homolog (Pten), mitogen-activated protein kinase-1 (MAPK-1), Glycogen synthase kinase-3-beta (GSK-3ß) and toll-like receptor-4 were evaluated. Treatment with NCMN improved memory, locomotion, neuronal differentiation by activating PI3K/AKT/GSK-3ß pathway. These results were confirmed by histological studies in hippocampus.


Assuntos
Doença de Alzheimer , Proteínas Proto-Oncogênicas c-akt , Ratos , Masculino , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Donepezila/farmacologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Acetilcolinesterase/metabolismo , Peptídeos beta-Amiloides/metabolismo , Ratos Wistar , Fosforilação
15.
Clin Ophthalmol ; 17: 3705-3715, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38073674

RESUMO

Purpose: To evaluate preoperative risk factors (mainly those related to corneal topography/tomography) for post-LASIK ectasia development. Methods: A retrospective case review for post-LASIK ectasia for myopia or myopic astigmatism. The evaluated data included preoperative subjective refraction, method of flap creation, and topometric/tomographic parameters from Oculus Pentacam, including subjective curvature pattern, topometric, elevation, and pachymetric indices from the Belin Ambrosio display "BAD", and the Pentacam Random Forest Index (PRFI). Moreover, preoperative ectasia detection indices were calculated (including Percentage of Tissue Altered "PTA" index, Randleman Ectasia Risk Score System "ERSS", and Navarro Index for Corneal Ectasia "NICE"). Results: Twenty-four eyes of 15 patients were enrolled. Concerning the risk factors, age was lower than 25 in 19 eyes (79%); flaps were created using a microkeratome in 17 eyes (70.8%); thinnest pachymetry was lower than 510µm in eight eyes (33%); total deviation from BAD was higher than 1.6 in 50%; Ambrósio's relational thickness (ART) max was lower than 340 in 45.83%; PTA index was higher than 40% in 16%; ERSS was more than 3 points in 62.5%; NICE was higher than 8 points in three eyes (12.5%); PRFI index was more than 0.125 in 87.5%; two eyes (8%) had no identifiable risk factors. Conclusion: Current ectasia risk assessment criteria were insufficient for detecting a relatively large number of cases. There is an unequivocal need for more information, which may be derived from biomechanical assessment and epithelial thickness mapping. Novel corneal tomography indices derived from artificial intelligence may increase accuracy in characterizing ectasia susceptibility.

16.
PLoS One ; 18(12): e0295941, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38134013

RESUMO

This work analyzes the stability and performance of an offshore solar-concentrated ocean thermal energy conversion system (SC-OTEC) tied to an onshore AC grid. The OTEC is a system where electricity is generated using small temperature differences between the warm surface and deep cold ocean water. Existing control methods for SC-OTEC systems lack coordination, hindering dynamic stability and effective damping for the synchronous generator (SG). These methods struggle to quickly adapt to sudden disturbances and lack the capability to adequately reject or compensate for such disturbances due to complex control constraints and computational demands. To this regard, a control strategy combining sliding mode control (SMC) and a power system stabilizer (PSS) to improve the SC-OTEC dynamic stability and damping features for the SG. Moreover, an auxiliary secondary automatic voltage regulator is assembled with a non-linear exciter system to provide damping features. The proposed PID-PSS and secondary AVR controller gains are adaptively tuned using a modified whale optimization algorithm with the balloon effect modulation. The studied SC-OTEC is tested through MATLAB/Simulink under a severe 3ϕ short-circuit fault, solar radiation variations, and a change in surface seawater temperature as well as changes in local loads. The final findings approved that the proposed control strategy preserves a strong performance and can mimic effectively the proposed SC-OTEC damping compared to the conventional system.


Assuntos
Aeronaves , Algoritmos , Animais , Cetáceos , Sistemas Computacionais , Eletricidade , Excipientes , Água
17.
Semin Dial ; 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37994191

RESUMO

A number of systems of feedback control during dialysis have been developed, which have the shared characteristic of prospectively measuring physiological parameters and then automatically altering dialysis parameters in real time according to a pre-specified dialysis prescription. These include feedback systems aimed at reducing intradialytic hypotension based on relative blood volume monitoring linked to adjustments in ultrafiltration and dialysate conductivity, and blood temperature monitoring linked to alterations in dialysate temperature. Feedback systems also exist that manipulate sodium balance during dialysis by assessing and adjusting dialysate conductivity. In this review article, we discuss the rationale for automated feedback systems during dialysis, describe how the different feedback systems work, and provide a review of the current evidence on their clinical effectiveness.

18.
BMC Complement Med Ther ; 23(1): 384, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891562

RESUMO

BACKGROUND: Methotrexate (MTX) is a common chemotherapeutic drug that inhibits DNA synthesis and induces apoptosis. Treatment with MTX increased CD73 expression, which leads to higher levels of extracellular adenosine. Adenosine levels are also high in the tumor microenvironment through Cancer cells metabolism. That promotes the survival of cancer cells and contributes to tumor immune evasion through the Adenosine 2a Receptor. A2A receptor antagonists are an emerging class of agents that treat cancers by enhancing immunotherapy, both as monotherapy and in combination with other therapeutic agents. Caffeine is an adenosine receptor antagonist. Herein, we demonstrate the ability of a novel well prepared and characterized nano formula CAF-FA-CS-NPs (D4) for A2aR blockade when combination with MTX to improve its antitumor efficacy by enhancing the immune system and eliminating immune suppression. METHODS: CAF-FA-CS-NPs (D4) were prepared and characterized for particle size, loading efficiency, and release profile. Molecular docking was used to validate the binding affinity of caffeine and folic acid to A2A receptor. The effects of the nano formula were evaluated on human liver cancer cells (HepG2), breast cancer cells (MCF-7), and MDA-MB-231, as well as normal human cells (WI-38). Different combination ratios of MTX and D4 were studied to identify the optimal combination for further genetic studies. RESULTS: Molecular docking results validated that caffeine and folic acid have binding affinity to A2A receptor. The CS-NPs were successfully prepared using ionic gelation method, with caffeine and folic acid being loaded and conjugated to the nanoparticles through electrostatic interactions. The CAF loading capacity in D4 was 77.9 ± 4.37% with an encapsulation efficiency of 98.5 ± 0.37. The particle size was optimized through ratio variations. The resulting nanoparticles were fully characterized. The results showed that (D4) had antioxidant activity and cytotoxicity against different cancer cells. The combination of D4 with MTX (IC50 D4 + 0.5 IC50 MTX) resulted in the downregulation of Bcl-2, FOXP3, CD39, and CD73 gene expression levels and upregulation of Bax and A2AR gene expression levels in HepG2 cells. CONCLUSIONS: This study suggests that CAF-FA-CS-NPs (D4) in combination with MTX may be a promising candidate for cancer immunotherapy, by inhibiting A2aR signaling and leading to improved immune activation and anti-tumor activity of MTX.


Assuntos
Quitosana , Nanopartículas , Neoplasias , Humanos , Metotrexato/farmacologia , Metotrexato/uso terapêutico , Ácido Fólico/uso terapêutico , Quitosana/química , Receptor A2A de Adenosina/uso terapêutico , Cafeína/farmacologia , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Nanopartículas/química , Imunoterapia , Adenosina , Microambiente Tumoral
19.
PLoS One ; 18(10): e0293246, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37862365

RESUMO

Due to the unpredictability of the majority of green energy sources (GESs), particularly in microgrids (µGs), frequency deviations are unavoidable. These factors include solar irradiance, wind disturbances, and parametric uncertainty, all of which have a substantial impact on the system's frequency. An adaptive load frequency control (LFC) method for power systems is suggested in this paper to mitigate the aforementioned issues. For engineering challenges, soft computing methods like the bat algorithm (BA), where it proves its effectiveness in different applications, consistently produce positive outcomes, so it is used to address the LFC issue. For online gain tuning, an integral controller using an artificial BA is utilized, and this control method is supported by a modification known as the balloon effect (BE) identifier. Stability and robustness of analysis of the suggested BA+BE scheme is investigated. The system with the proposed adaptive frequency controller is evaluated in the case of step/random load demand. In addition, high penetrations of photovoltaic (PV) sources are considered. The standard integral controller and Jaya+BE, two more optimization techniques, have been compared with the suggested BA+BE strategy. According to the results of the MATLAB simulation, the suggested technique (BA+BE) has a significant advantage over other techniques in terms of maintaining frequency stability in the presence of step/random disturbances and PV source. The suggested method successfully keeps the frequency steady over I and Jaya+BE by 61.5% and 31.25%, respectively. In order to validate the MATLAB simulation results, real-time simulation tests are given utilizing a PC and a QUARC pid_e data acquisition card.


Assuntos
Algoritmos , Modelos Teóricos , Simulação por Computador , Fontes de Energia Elétrica , Fontes Geradoras de Energia
20.
Microorganisms ; 11(9)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37764207

RESUMO

Cancers of the biliary tract are more common in Asia than in Europe, but are highly lethal due to delayed diagnosis and aggressive tumor biology. Since the biliary tract is in direct contact with the gut via the enterohepatic circulation, this suggests a potential role of gut microbiota, but to date, the role of gut microbiota in biliary tract cancers has not been elucidated. This scoping review compiles recent data on the associations between the gut microbiota and diagnosis, progression and prognosis of biliary tract cancer patients. Systematic review of the literature yielded 154 results, of which 12 studies and one systematic review were eligible for evaluation. The analyses of microbiota diversity indices were inconsistent across the included studies. In-depth analyses revealed differences between gut microbiota of biliary tract cancer patients and healthy controls, but without a clear tendency towards particular species in the studies. Additionally, most of the studies showed methodological flaws, for example non-controlling of factors that affect gut microbiota. At the current stage, there is a lack of evidence to support a general utility of gut microbiota diagnostics in biliary tract cancers. Therefore, no recommendation can be made at this time to include gut microbiota analyses in the management of biliary tract cancer patients.

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