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Separation of mononuclear cells from progenitor products by a novel inertial microfluidic method
No full textMononuclear cells (MNCs), a type of leukocyte, require enrichment owing to their rarity for research and clinical applications. The enrichment of MNCs is generally performed via conventional methods (e.g., density gradient centrifugation). However, these methods have downsides, such as being labor intensive, energy and time consuming, and requiring advanced equipment. Therefore, inertial microfluidics has recently drawn widespread attention as a way to overcome these limitations. This work aims to investigate MNC separation using a novel spiral inertial microfluidic system design. After MNCs were enriched by Ficoll stratification, the cells were separated according to their size and deformability properties by passing through the microfluidic system. In the final step, various cell markers were examined for characterization in these cells collected at outlets. In this paper, we determined that MNCs obtained from three different hematological products could be sorted with a recovery rate of 97.5% and a purity level of 84%, whereas red blood cells (RBCs) had a depletion ratio of 80% using Sunflower-designed microfluidic system. The loss of MNCs in this system was much lower than that in density gradient centrifugation. The separation technique studied here has several advantages, such as continuous processing, a high operation flow rate (e.g., 0.7 ml/min), simplifying the operative procedures for automation, and creating no clogging problems. Additionally, this technique can be easily integrated with downstream applications, such as direct analysis of MNCs via a flow cytometer, and can reduce the number of man-hand manipulation processes
Fonolojik farkındalık becerilerinin ve görsel uzamsal algının matematik performansına etkisi
Full text linkMatematiksel yeterlilik, günlük hayatta önemli bir yere sahiptir. Sözel sayı becerileri sayı bilgisinin gelişmesini sağlayarak matematiksel becerilerin temelini oluşturur. Matematiksel işlemler fonolojik becerilerin ve sayı sözcüklerinin kullanımını içeren saymaya dayalı bir beceridir. Fonolojik farkındalık, bir üst dil becerisidir ve dilin ses yapısının analiz edilmesini sağlamaktadır. Sözel sayı becerileri, fonolojik farkındalık becerilerinden ve görsel-uzamsal süreçlerden etkilenmektedir. Görsel uzamsal beceriler matematiksel işlem öğrenme için gereklidir. Bu çalışmada 7;0–8;11 yaş aralığında normal gelişim gösteren 40 katılımcının fonolojik farkındalık becerilerinin ve görsel uzamsal algı performanslarının matematiksel performansa etkisi incelenmiştir. Örneklem büyüklüğü hesabı için G*Power 3.1.9.4 paket programı ve Regresyon Testi çözümlenmesi kullanılmıştır. Çocukların fonolojik farkındalık düzeyleri ile matematiksel performansları arasında orta düzeyde pozitif ilişki görülmüştür (r=0,370; p=0,019). Katılımcılara WISC-R Zeka Testi, Türkçe Okul Çağı Dil Gelişimi Testi (TODİL), Frostig Gelişimsel Görsel Algı Testi, Fonolojik Farkındalık Testi ve rutin olmayan matematiksel problemler uygulanmıştır. Çocukların TODİL konuşma bileşke performansı ile matematiksel performansları arasında orta düzeyde pozitif ilişki görülmüştür (p=0,049, r=0,313). Analiz sonuçlarına göre, fonolojik farkındalık (β=0,34, p<0,05) ve TODİL konuşma bileşke performansı (β=0,29, p<0,05) matematiksel performans üzerinde pozitif ve istatistiksel olarak anlamlı bir etkiye sahiptir. Fonolojik farkındalık becerilerinin ve Türkçe Okul Çağı Dil Gelişim Testi konuşma bileşke performansının matematiksel performans üzerinde anlamlı bir etkiye sahip olduğu ve gelişimsel görsel algının matematik performansı üzerinde etki etmediği sonucuna ulaşılmıştır.Mathematical competence holds a significant place in daily life. Verbal number skills facilitate the development of numerical knowledge, forming the foundation of mathematical skills. Mathematical operations are counting-based skills involving the use of phonological skills and number words. Phonological awareness is a metalinguistic skill that enables the analysis of the sound structure of language. Verbal number skills are influenced by phonological awareness skills and visual-spatial processes. Visual-spatial skills are essential for learning mathematical operations. This study examined the effects of phonological awareness skills and visual-spatial perception performances on the mathematical performance of 40 normally developing participants aged 7;0–8;11. The sample size was calculated using the G*Power 3.1.9.4 software package and Regression Test analysis. A moderate positive correlation was found between children's phonological awareness levels and their mathematical performance (r=0.370; p=0.019). Participants were administered the WISC-R Intelligence Test, Test of Language Development-Primary: Fourth Edition (TOLD-P4), Frostig Developmental Visual Perception Test, Phonological Awareness Test, and non-routine mathematical problems. A moderate positive correlation was observed between children's TOLD-P4 speech composite performance and their mathematical performance (p=0.049, r=0.313). According to the analysis results, phonological awareness (β=0.34, p<0.05) and TOLD-4 speech composite performance (β=0.29, p<0.05) had a positive and statistically significant effect on mathematical performance. The study concluded that phonological awareness skills and the Test of Language Development-Primary: Fourth Edition speaking composite performance had a significant effect on mathematical performance, whereas developmental visual perception did not have an effect on mathematical performance
A new design of arithmetic and logic unit for enhancing the security of future internet of things devices using quantum-dot technology
No full textThe Internet of Things (IoT) is a network of interconnected devices that collect, monitor, analyze, and exchange data. This technology plays a crucial role in the smart city infrastructure by seamlessly interconnecting various nodes. The extensive application and recognition of IoT across multiple city domains, such as healthcare, transportation, energy, education, and agriculture, bring significant challenges, with security among the most pressing. Traditional hardware technologies like Complementary Metal Oxide Semiconductor (CMOS) and Very Large Scale Integration (VLSI) suffer from limitations such as high power consumption and insufficient scalability, which hinder secure and sustainable IoT deployment. Such limitations have prompted the need to seek other technologies that would serve the dual purpose of providing security as well as energy. Quantum-based technologies can become adequate candidates offering promising solutions to make IoT devices and sustainable systems more secured. Quantum-dot Cellular Automata (QCA) has been proposed as a nanotechnology with the potential of consuming ultra-low powers, less area, and high-speed operation. QCA enhances security through sustainable computing objectives by minimizing energy usage. To improve the future security and efficiency of IoT hardware, this paper suggests a QCA-based Arithmetic Logic Unit (ALU). This ALU can generate more than 12 logical and arithmetic operations. Designed together with the majority gates, XOR gates, multiplexers, and full adders, the ALU is simulated using the QCA-Designer 2.0.3. Simulated results indicate improvements in the number of cells and reduced occupied area relative to the earlier designs. These results indicate the potential of QCA technology in enabling secure, energy-efficient, and compact computing architecture applicable in the future IoT
Evaluating employee satisfaction in a green-certified public building: the case of Küçükçekmece Municipality
Full text linkAlthough green building certifications aim to promote environmentally sustainable design, their impact on user experience and spatial satisfaction remains underexplored. This gap raises questions about the extent to which sustainability goals align with user expectations. This study investigates employee satisfaction in the K & uuml;& ccedil;& uuml;k & ccedil;ekmece Municipality New Service Building, the first public administration building in T & uuml;rkiye certified by BREEAM. Multiple variables, including physical environmental comfort, perception of green building features, functionality, and motivation, were analyzed. A mixed-method research design was used where quantitative data were collected using 5-point Likert scale surveys and qualitative data were collected via interviews with open-ended questions. Frequency analysis, Principal Component Analysis (PCA), t-test, ANOVA, and Chi-Squares test were used to analyze the study data. The results indicated that certain environmental factors, including lighting and ergonomics, were associated with relatively higher satisfaction levels, while there was significant dissatisfaction as regards indoor air quality and thermal comfort. Furthermore, it was found that demographic variables, including gender and age, had significant effects on motivation levels. The study results suggested that the physical environment in sustainable public buildings should be assessed not only in terms of technical but also psychosocial aspects
SYNTHESIS, CHARACTERISATION, AND INVESTIGATION OF THE ANTICANCER POTENTIAL OF CARMOFUR-LOADED SILVER NANOPARTICLES
No full textObjective: The term "triple-negative breast cancer" (TNBC) is used to describe tumours that do not express oestrogen receptor (ER), progesterone receptor (PR), or human epidermal growth factor receptor 2 (HER2). TNBC tends to be more aggressive than other types of breast cancer. Current antineoplastic drugs have limited treatment options for malignant breast cancer owing to their narrow therapeutic index, toxicity, resistance, and nonselectivity. Therefore, there is a need for the prompt development of new medicinal drugs for TNBC. Here, we investigated the growth inhibition potential of carmofur-bonded silver nanoparticles (AgNPs-Car) on two TNBC cell lines, MDA-MB-231 and 4T1, and compared the effects with non-cancerous Human umbilical vein endothelial cells (HUVECs). Material and Methods: AgNPs-Car were synthesised and characterised by FTIR, DLS, SEM, and EDX. The anticancer effect was evaluated using a 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay. Results: AgNPs-Car was determined to be predominantly more effective than Car alone. Mainly, 4T1 cells were 5.7-fold more sensitive to AgNPs-Car than Car alone. While AgNPs showed no considerable toxicity on HUVECs, they significantly induced the cytotoxicity of MDA-MB-231 and 4T1 cells. Conclusion: Our results showed that AgNPs-Car is a promising anticancer agent due to its highly potent and selective growth inhibitory effect on TNBC cells
Cardiotoxicity caused by acrylamide in rats can be alleviated as a result of suppression of oxidative stress, endoplasmic reticulum stress, inflammation, and apoptosis by morin treatment
No full textObjective(s): The present study investigated whether morin has a protective effect against ACRinduced cardiac toxicity. Materials and Methods: In this study, oxidative stress, inflammation, endoplasmic reticulum stress (ERS), and apoptosis markers in heart tissues were analyzed by different methods after ACR (38.27 mg/kg) and morin (50 or 100 mg/kg) oral administration for ten days to Sprague Dawley rats. Results: The data obtained showed that ACR induced lipid peroxidation by decreasing superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) enzyme activities, glutathione (GSH) levels and nuclear factor erythroid 2-related factor 2 (Nrf-2), heme oxygenase-1 (HO-1), NAD(P)H dehydrogenase quinone 1 (NQO1), glutamate-cysteine ligase modifier subunit (GCLM), and glutamate-cysteine ligase catalytic subunit (GCLC) gene expressions. On the other hand, these markers approached the control group levels after morin treatment. Moreover, morin suppressed ACR-induced inflammatory genes. Morin down-regulated the related genes by reducing the ERS, exacerbated after ACR administration. In addition, it was observed that B-cell lymphoma-2 (Bcl-2) associated X protein (Bax), caspase-3, and apoptotic peptidase activating factor 1 (apaf-1) expressions, elevated by ACR in the heart tissue, were suppressed after morin administration. Moreover, Bcl-2 expression was triggered by morin treatment. Thus, morin suppressed ACR-induced apoptosis. Conclusion: Taken together, morin may protect against ACR-induced cardiac injury by suppressing oxidative stress, inflammation, ERS, and apoptosis
Ganoderma lucidum: An Emerging Nutritional Approach to Manage Depression
Full text linkDepression is a highly prevalent neuropsychiatric illness that significantly reduces the quality of life of the patients. While psychotherapy and pharmacotherapy remain the most common treatments, their limitations, including treatment resistance and adverse side effects, have driven interest in alternative therapies to complement conventional antidepressant therapies. Ganoderma lucidum (G. lucidum), a medicinal mushroom, is gaining attention for its potential in managing depression symptoms, largely attributed to its bioactive compounds, polysaccharides, and triterpenoids. These compounds collectively exhibit antidepressant-like effects in animal models of depression, mainly acting through mechanisms such as modulating the monoamine neurotransmission system, enhancing BDNF expression, and balancing pro- and anti-inflammatory cytokines in depressive animals. Furthermore, clinical studies suggest that G. lucidum may alleviate depression-like symptom in humans. This review explores the antidepressant potential of G. lucidum and the mechanisms by which its primary bioactive compounds exert their effects
Proposed receptor-mediated mechanisms of melatonin in nitroglycerin-induced migraine-like hyperalgesic conditions in rats
No full textMelatonin has a therapeutic effect on migraine, but the mechanisms underlying its antimigraine effect have not been elucidated. This study therefore investigated for the first time the receptor-mediated mechanisms of action of melatonin in nitroglycerin (NTG)- induced migraine-like hyperalgesic conditions in rats. Melatonin, nonselective MT1/MT2 antagonist luzindole, selective MT2 antagonist DH97 or potent MT3 antagonist prazosin, alone or in various combinations, were administered to NTG-induced migraine rats and ex-vivo meningeal preparations. Basal and drug-treated pain behaviors were assessed with the von-Frey test. CGRP levels in the trigeminal ganglia, trigeminal nucleus caudalis (TNC) and ex-vivo superfusate medium, as well as c-fos level in the TNC, were measured by ELISA. Meningeal mast cells were stained with toluidine-blue and examined histologically for their activation and count. Melatonin mitigated mechanical hyperalgesia, and c-fos and CGRP expression in the TNC, CGRP expression in trigeminal ganglia, CGRP release from meningeal afferents, all of which were induced by NTG, and also suppressed NTG-stimulated meningeal mast cell activation. The effects of melatonin were abolished in the presence of luzindole and DH97, respectively. However, prazosin did not reverse the effects of melatonin except for mechanical hyperalgesia. Luzindole and DH97 in combinations with prazosin also canceled the effects of melatonin, respectively, other than CGRP expression in the TNC. Melatonin exerts its anti-hyperalgesic effects through modulation of trigeminal expression and meningeal release of CGRP, and meningeal mast cell activation in experimental migraine-like conditions. The effects of melatonin are mainly mediated by MT2 receptors, without excluding a possible role for MT1. (c) 2024 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies
Solvent-mediated dynamics of diphtheria toxin and NAD interaction
Full text linkThe interaction between diphtheria toxin (DT) and nicotinamide adenine dinucleotide (NAD) is central to DT's enzymatic activity, which involves ADP-ribosylation of eukaryotic elongation factors. This study aims to elucidate how solvent environments influence the thermodynamic and structural properties of the DT-NAD interaction. Using Raman Spectroscopy, and complementary techniques, we analyzed two different DTs, and by using Differential Scanning Calorimetry (DSC) we try to understand DT-NAD binding under varying solvent conditions, including distilled water, phosphate-buffered saline (PBS), and different concentrations of dimethyl sulfoxide (DMSO). Our findings reveal that solvent composition significantly alters the thermal stability and binding dynamics of DT. Notably, DSC data showed distinct shifts in melting temperatures (Tm) and enthalpy changes (Delta H) across solvents, with 100% DMSO disrupting the interaction and causing structural denaturation. This study underscores the critical role of solvent selection in modulating protein-ligand interactions and offers valuable insights into the molecular dynamics of DT. These findings have broad implications for biochemical research and therapeutic applications involving protein stability in diverse environments