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1.
Int J Biol Macromol ; : 131856, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38693000

RESUMEN

Biomacromolecules derived from natural sources offer superior biocompatibility, biodegradability, and water-holding capacity, which make them promising scaffolds for tissue engineering. Psyllium seed has gained attention in biomedical applications recently due to its gel-forming ability, which is provided by its polysaccharide-rich content consisting mostly of arabinoxylan. This study focuses on the extraction and gelation of Psyllium seed hydrocolloid (PSH) in a single-step water-based protocol, and scaffold fabrication using freeze-drying method. After characterization of the scaffold, including morphological, mechanical, swelling, and protein adsorption analyses, 3D cell culture studies were done using NIH-3 T3 fibroblast cells on PSH scaffold, and cell viability was assessed using Live/Dead and Alamar Blue assays. Starting from day 1, high cell viability was obtained, and it reached 90 % at the end of 15-day culture period. Cellular morphology on PSH scaffold was monitored via SEM analysis; cellular aggregates then spheroid formation were observed throughout the study. Collagen Type-I and F-actin expressions were followed by immunostaining revealing a 9- and 10-fold increase during long-term culture. Overall, a single-step and non-toxic protocol was developed for extraction and gelation of PSH. Obtained results unveiled that PSH scaffold provided a favorable 3D microenvironment for cells, holding promise for further tissue engineering applications.

2.
ACS Omega ; 9(13): 14955-14962, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38585102

RESUMEN

Magnetic levitation (MagLev) is a powerful and versatile technique that can sort objects based on their density differences. This paper reports the sorting of SH-SY5Y cells for neuronal differentiation by the MagLev technique. Herein, SH-SY5Y cells were differentiated with retinoic acid (RA) and brain-derived neurotrophic factor (BDNF). Neuronal differentiation was confirmed by neurite extension measurement and the immunostaining assay. Neurites reached the maximum length on day 9 after sequential treatment with RA-BDNF. Neuronal marker expression of un-/differentiated cells was investigated by ß-III tubulin and neuronal nuclei (NeuN) and differentiated cells exhibited a higher fluorescence intensity compared to un-/differentiated cells. MagLev results revealed that the density of differentiated SH-SY5Y cells gradually increased from 1.04 to 1.06 g/mL, while it remained stable at 1.05 g/mL for un-/differentiated cells. These findings signified that cell density would be a potent indicator of neuronal differentiation. Overall, it was shown that MagLev methodology can provide rapid, label-free, and easy sorting to analyze the differentiation of cells at a single-cell level.

3.
ACS Sens ; 9(4): 2043-2049, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38520356

RESUMEN

Extracellular vesicles, especially exosomes, have attracted attention in the last few decades as novel cancer biomarkers. Exosomal membrane proteins provide easy-to-reach targets and can be utilized as information sources of their parent cells. In this study, a MagLev-based, highly sensitive, and versatile biosensor platform for detecting minor differences in the density of suspended objects is proposed for exosome detection. The developed platform utilizes antibody-functionalized microspheres to capture exosomal membrane proteins (ExoMPs) EpCAM, CD81, and CD151 as markers for cancerous exosomes, exosomes, and non-small cell lung cancer (NSCLC)-derived exosomes, respectively. Initially, the platform was utilized for protein detection and quantification by targeting solubilized ExoMPs, and a dynamic range of 1-100 nM, with LoD values of 1.324, 0.638, and 0.722 nM for EpCAM, CD81, and CD151, were observed, respectively. Then, the sensor platform was tested using exosome isolates derived from NSCLC cell line A549 and MRC5 healthy lung fibroblast cell line. It was shown that the sensor platform is able to detect and differentiate exosomal biomarkers derived from cancerous and non-cancerous cell lines. Overall, this innovative, simple, and rapid method shows great potential for the early diagnosis of lung cancer through exosomal biomarker detection.


Asunto(s)
Molécula de Adhesión Celular Epitelial , Exosomas , Neoplasias Pulmonares , Exosomas/química , Humanos , Neoplasias Pulmonares/patología , Molécula de Adhesión Celular Epitelial/metabolismo , Tetraspanina 28/metabolismo , Tetraspanina 28/análisis , Técnicas Biosensibles/métodos , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Biomarcadores de Tumor/análisis , Tetraspanina 24 , Células A549
4.
Macromol Biosci ; 24(4): e2300402, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38102867

RESUMEN

This study describes the formation, size control, and penetration behavior of polymer nanodots (Pdots) consisting of single or few chain polythiophene-based conjugated polyelectrolytes (CPEs) via nanophase separation between good solvent and poor solvent of CPE. Though the chain singularity may be associated with dilution nanophase separation suggests that molecules of a good solvent create a thermodynamically driven solvation layer surrounding the CPEs and thereby separating the single chains even in their poor solvents. This statement is therefore corroborated with emission intensity/lifetime, particle size, and scattering intensity of polyelectrolyte in good and poor solvents. Regarding the augmented features, Pdots are implemented into cell imaging studies to understand the nuclear penetration and to differentiate the invasive characteristics of breast cancer cells. The python based red, green, blue (RGB) color analysis   depicts that Pdots have more nuclear penetration ability in triple negative breast cancer cells due to the different nuclear morphology in shape and composition and Pdots have penetrated cell membrane as well as extracellular matrix in spheroid models. The current Pdot protocol and its utilization in cancer cell imaging are holding great promise for gene/drug delivery to target cancer cells by explicitly achieving the very first priority of nuclear intake.


Asunto(s)
Colorantes Fluorescentes , Puntos Cuánticos , Semiconductores , Polímeros , Polielectrolitos , Solventes
5.
Tissue Eng Part A ; 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37974427

RESUMEN

Patterning cells to create three-dimensional (3D) cell culture models by magnetic manipulation is a promising technique, which is rapid, simple, and cost-effective. This study introduces a new biopatterning approach based on magnetic manipulation of cells with a bioink that consists alginate, cells, and magnetic nanoparticles. Plackett-Burman and Box-Behnken experimental design models were used to optimize bioink formulation where NIH-3T3 cells were utilized as a model cell line. The patterning capability was confirmed by light microscopy through 7 days culture time. Then, biopatterned 3D cardiac structures were formed using H9c2 cardiomyocyte cells. Cellular and extracellular components, F-actin and collagen Type I, and cardiac-specific biomarkers, Troponin T and MYH6, of biopatterned 3D cardiac structures were observed successfully. Moreover, Doxorubicin (DOX)-induced cardiotoxicity was investigated for developed 3D model, and IC50 value was calculated as 8.1 µM for biopatterned 3D cardiac structures, which showed higher resistance against DOX-exposure compared to conventional two-dimensional cell culture. Hereby, developed biopatterning methodology proved to be a simple and rapid approach to fabricate 3D cardiac models, especially for drug screening applications.

6.
Int J Stroke ; 18(9): 1112-1120, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37277922

RESUMEN

BACKGROUND: Adenovirus-based COVID-19 vaccines are extensively used in low- and middle-income countries (LMICs). Remarkably, cases of cerebral venous sinus thrombosis due to vaccine-induced immune thrombotic thrombocytopenia (CVST-VITT) have rarely been reported from LMICs. AIMS: We studied the frequency, manifestations, treatment, and outcomes of CVST-VITT in LMICs. METHODS: We report data from an international registry on CVST after COVID-19 vaccination. VITT was classified according to the Pavord criteria. We compared CVST-VITT cases from LMICs to cases from high-income countries (HICs). RESULTS: Until August 2022, 228 CVST cases were reported, of which 63 were from LMICs (all middle-income countries [MICs]: Brazil, China, India, Iran, Mexico, Pakistan, Turkey). Of these 63, 32 (51%) met the VITT criteria, compared to 103 of 165 (62%) from HICs. Only 5 of the 32 (16%) CVST-VITT cases from MICs had definite VITT, mostly because anti-platelet factor 4 antibodies were often not tested. The median age was 26 (interquartile range [IQR] 20-37) versus 47 (IQR 32-58) years, and the proportion of women was 25 of 32 (78%) versus 77 of 103 (75%) in MICs versus HICs, respectively. Patients from MICs were diagnosed later than patients from HICs (1/32 [3%] vs. 65/103 [63%] diagnosed before May 2021). Clinical manifestations, including intracranial hemorrhage, were largely similar as was intravenous immunoglobulin use. In-hospital mortality was lower in MICs (7/31 [23%, 95% confidence interval (CI) 11-40]) than in HICs (44/102 [43%, 95% CI 34-53], p = 0.039). CONCLUSIONS: The number of CVST-VITT cases reported from LMICs was small despite the widespread use of adenoviral vaccines. Clinical manifestations and treatment of CVST-VITT cases were largely similar in MICs and HICs, while mortality was lower in patients from MICs.


Asunto(s)
Trombosis de los Senos Intracraneales , Accidente Cerebrovascular , Trombocitopenia , Vacunas , Humanos , Femenino , Adulto Joven , Adulto , Vacunas contra la COVID-19/efectos adversos , Países en Desarrollo , Trombocitopenia/epidemiología , Trombocitopenia/etiología , Trombosis de los Senos Intracraneales/epidemiología , Trombosis de los Senos Intracraneales/etiología
7.
Analyst ; 148(4): 898-905, 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36688900

RESUMEN

Paper-based microfluidics is an emerging analysis tool used in various applications, especially in point-of-care (PoC) diagnostic applications, due to its advantages over other types of microfluidic devices in terms of simplicity in both production and operation, cost-effectiveness, rapid response time, low sample consumption, biocompatibility, and ease of disposal. Recently, various techniques have been developed and utilized for the fabrication of paper-based microfluidics, such as photolithography, micro-embossing, wax and PDMS printing, etc. In this study, we offer a fabrication methodology for a microfluidic paper-based immunosorbent assay (µPISA) platform and the detection of Hepatitis C Virus (HCV) was carried out to validate this platform. A laser ablation technique was utilized to form hydrophobic barriers easily and rapidly, which was the major advantage of the developed fabrication methodology. The characterization of the µPISA platform was performed in terms of micro-channel properties using bright-field (BF) microscopy, and surface properties using scanning electron microscopy (SEM). At the same time, sample volume and liquid handling capacity were analyzed quantitatively. Ablation speed (S) and laser power (P) were optimized, and it was shown that one combination (10P60S) provided minimal deviation in micro-channel dimensions and prevented deterioration of hydrophobic barriers. Also, the minimum hydrophobic barrier width, which prevents cross-barrier bleeding, was determined to be 255.92 ± 10.01 µm. Furthermore, colorimetric HCV NS3 detection was implemented to optimize and validate the µPISA platform. Here, HCV NS3 in both PBS and human blood plasma was successfully detected by the naked eye at concentrations as low as 1 ng mL-1 and 10 ng mL-1, respectively. Moreover, the limit of detection (LoD) values for HCV NS3 were acquired as 0.796 ng mL-1 in PBS and 2.203 ng mL-1 in human blood plasma with a turnaround time of 90 min. In comparison with conventional ELISA, highly sensitive and rapid HCV NS3 detection was accomplished colorimetrically on the developed µPISA platform.


Asunto(s)
Hepatitis C , Técnicas Analíticas Microfluídicas , Humanos , Microfluídica/métodos , Inmunoadsorbentes , Hepacivirus , Colorimetría , Hepatitis C/diagnóstico
8.
Biomater Sci ; 10(23): 6707-6717, 2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36278818

RESUMEN

A new generation of bio-inks that are soft, viscous enough, stable in cell culture, and printable at low printing pressures is required in the current state of 3D bioprinting technology. Hydrogels can meet these features and can mimic the microenvironment of soft tissues easily. Hydrocolloids are a group of hydrogels which have a suitable gelling capacity and rheological properties. According to the literature, polysaccharide-based hydrocolloids are used in the food industry, wound healing technologies, and tissue engineering. Quince seed hydrocolloids (QSHs), which consist of mostly glucuronoxylan, can easily be obtained from quince seeds by water extraction. In this study, the use of a QSH as a bio-ink was investigated. The suitability of QSH for the printing process was assessed by rheological, uniformity and pore factor analyses. Appropriate printing parameters were determined and the characterization of the bioprinted QSHs was performed by SEM analysis, water uptake capacity measurement, and protein adsorption assay. The bioprinted QSHs had excellent water uptake capacity and showed suitable protein adsorption behaviour. Analyses of the biocompatibility and cellular viability of bioprinted QSHs were conducted using NIH-3T3 fibroblast cells and the results were found to be high during short and long-term cell culture periods. It was proved that QSH is a highly promising bio-ink for 3D bioprinting and further tissue engineering applications.


Asunto(s)
Bioimpresión , Bioimpresión/métodos , Tinta , Hidrogeles , Coloides , Agua
9.
Neurologist ; 27(6): 309-312, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-35051967

RESUMEN

BACKGROUND: The aim of this study is to reveal the relationship between end-tidal CO 2 (EtCO 2 ) values with infarct volume and early prognosis in patients diagnosed with acute ischemic stroke in the emergency department. MATERIALS AND METHODS: This prospective cross-sectional study was conducted in a tertiary hospital. The demographics, characteristics, EtCO 2 , volume of the stroke area on diffusion-weighted magnetic resonance imaging and the modified Rankin Scale (mRS) of the patients were recorded. The values calculated at admission and at discharge were labeled as "mRS-1" and "mRS-2," respectively, and the mRS-2 measurement was used as a prognostic indicator. The "good" and the "poor" functional outcomes were defined as mRS ≤2 and mRS >2, respectively. Correlations between levels of EtCO 2 and infarct volume, mRS were calculated. RESULTS: In total, 44 patients were included in the study. The median age of the patients was 69 years (interquartile range; 16; min-max: 35 to 88 y) and 68.2% of them were male. In the univariate logistic regression models of the mRS-2 [0 to 2 (0) and 3 to 6 (1)], all variables were not statistically significant to predict mRS-2 group. There were statistically significant differences in EtCO 2 values between mRS-1 ( P =0.03) and mRS-2 ( P =0.04). A negative moderate correlation was found between EtCO 2 and mRS-2 ( r =-0.410; P =0.006). The correlation between EtCO 2 and infarct volume was not statistically significant ( r =-0.256; P =0.093). CONCLUSIONS: This study highlights the importance of capnography follow-up of patients with acute ischemic stroke. In patients with acute ischemic stroke, the EtCO 2 value measured at the time of admission is lower in the group with high mRS at both admission and discharge.


Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Masculino , Anciano , Femenino , Estudios Prospectivos , Estudios Transversales , Resultado del Tratamiento , Accidente Cerebrovascular/diagnóstico , Pronóstico , Infarto
10.
Int J Biol Macromol ; 180: 729-738, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33757854

RESUMEN

Natural gums and mucilages from plant-derived polysaccharides are potential candidates for a tissue-engineering scaffold by their ability of gelation and biocompatibility. Herein, we utilized Glucuronoxylan-based quince seed hydrogel (QSH) as a scaffold for tissue engineering applications. Optimization of QSH gelation was conducted by varying QSH and crosslinker glutaraldehyde (GTA) concentrations. Structural characterization of QSH was done by Fourier Transform Infrared Spectroscopy (FTIR). Furthermore, morphological and mechanical investigation of QSH was performed by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). The protein adsorption test revealed the suitability of QSH for cell attachment. Biocompatibility of QSH was confirmed by culturing NIH-3T3 mouse fibroblast cells on it. Cell viability and proliferation results revealed that optimum parameters for cell viability were 2 mg mL-1 of QSH and 0.03 M GTA. SEM and DAPI staining results indicated the formation of spheroids with a diameter of approximately 300 µm. Furthermore, formation of extracellular matrix (ECM) microenvironment was confirmed with the Collagen Type-I staining. Here, it was demonstrated that the fabricated QSH is a promising scaffold for 3D cell culture and tissue engineering applications provided by its highly porous structure, remarkable swelling capacity and high biocompatibility.


Asunto(s)
Hidrogeles/química , Rosaceae/química , Semillas/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Xilanos/química , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/metabolismo , Materiales Biocompatibles/farmacología , Supervivencia Celular/efectos de los fármacos , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Matriz Extracelular/ultraestructura , Hidrogeles/metabolismo , Ratones , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Células 3T3 NIH , Porosidad , Espectroscopía Infrarroja por Transformada de Fourier , Xilanos/metabolismo
11.
ACS Appl Bio Mater ; 4(2): 1794-1802, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-35014525

RESUMEN

Tunable and reproducible size with high circularity is an important limitation to obtain three-dimensional (3D) cellular structures and spheroids in scaffold free tissue engineering approaches. Here, we present a facile methodology based on magnetic levitation (MagLev) to fabricate 3D cellular structures rapidly and easily in high-volume and low magnetic field. In this study, 3D cellular structures were fabricated using magnetic levitation directed assembly where cells are suspended and self-assembled by contactless magnetic manipulation in the presence of a paramagnetic agent. The effect of cell seeding density, culture time, and paramagnetic agent concentration on the formation of 3D cellular structures was evaluated for NIH/3T3 mouse fibroblast cells. In addition, magnetic levitation guided cellular assembly and 3D tumor spheroid formation was examined for five different cancer cell lines: MCF7 (human epithelial breast adenocarcinoma), MDA-MB-231 (human epithelial breast adenocarcinoma), SH-SY5Y (human bone-marrow neuroblastoma), PC-12 (rat adrenal gland pheochromocytoma), and HeLa (human epithelial cervix adenocarcinoma). Moreover, formation of a 3D coculture model was successfully observed by using MDA-MB-231 dsRED and MDA-MB-231 GFP cells. Taken together, these results indicate that the developed MagLev setup provides an easy and efficient way to fabricate 3D cellular structures and may be a feasible alternative to conventional methodologies for cellular/multicellular studies.


Asunto(s)
Materiales Biocompatibles/química , Técnicas de Cocultivo , Imagenología Tridimensional , Esferoides Celulares/química , Ingeniería de Tejidos , Andamios del Tejido/química , Animales , Línea Celular Tumoral , Humanos , Campos Magnéticos , Ensayo de Materiales , Tamaño de la Partícula , Ratas
12.
Brain Circ ; 6(3): 191-195, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33210044

RESUMEN

BACKGROUND: Transient ischemic attack (TIA) is a common neurovascular disorder associated with a higher risk of stroke within the first 24 h after the first event. Acute cerebral and arterial neuroimaging combined with long-term electrocardiography (ECG) monitoring have been proven to be useful in determining etiology. Cardio-embolism constitutes 20%-26% etiology of TIAs most of them with atrial fibrillation (AF). Investigation of AF after TIA is very important because oral anticoagulants can reduce the risk of subsequent stroke by two thirds. MATERIALS AND METHODS: The present study included 45 patients suffering from TIA with undetermined source according to the Trial of Org 10172 in Acute Stroke Treatment criteria; the control group (n = 45) was selected from the patients admitted to cardiology outpatient clinic with nonspecific complaints without cerebrovascular and/or cardiovascular disease. All patients underwent echocardiography and 24 h Holter ECG monitoring (HM). RESULTS: There was no significant difference between the patient group and the control group in terms of age and gender. Cholesterol, low-density lipoprotein and urea levels, left atrium diameters and the incidence of hypertension, coronary artery diseases, and AF were significantly higher in TIA group (P < 0.05). In the results of HM, there were six patients with AF in the study group, and in the control group, there was no patients with AF (P = 0.03). DISCUSSION AND CONCLUSION: In acute phase of TIA, 24 h HM is important for determining the etiology and selecting an appropriate treatment that can protect patients from subsequent strokes.

13.
Analyst ; 145(17): 5816-5825, 2020 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-32648883

RESUMEN

This work describes development of smartphone-assisted magnetic levitation assay for Point-of-Care (PoC) applications. Magnetic levitation is a technique that detects and separates particles based on their density differences in a magnetic field. Observation of the levitated micro-particles is mainly performed by light microscope or additional optical components, which mostly limits applicability of the magnetic levitation technique for PoC diagnostics. In this paper, we demonstrated the capability of the smartphone assisted-magnetic levitation platform for Hepatitis C (HCV) detection assay. This method utilizes microsensor beads (MS beads) that are functionalized with anti-HCV NS3 antibody. First, the magnetic levitation platform was optimized via density marker polyethylene beads (DMB); then HCV NS3 protein was successfully detected based on levitation height differences of MS beads caused by density changes. The capability of the magnetic levitation platform for HCV detection was determined as almost 10-fold sensitive compared to conventional techniques such as enzyme-linked immunosorbent assay (ELISA). The imaging capability and resolution of the setup was improved over previously used configurations, and the developed platform enabled visualization of micro-scale objects only by smartphone assistance. This method requires no power, it is an easy-to-use and cost effective, therefore it could be easily adaptable to varied sensing assays as PoC tool.

14.
Int J Biol Macromol ; 139: 1054-1062, 2019 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-31404597

RESUMEN

Electrospun collagen is commonly used as a scaffold in tissue engineering applications since it mimics the content and morphology of native extracellular matrix (ECM) well. This report describes "toxic solvent free" fabrication of electrospun hybrid scaffold consisting of Collagen (Col) and Poly(l-lactide-co-ε-caprolactone) (PLLCL) for three-dimensional (3D) cell culture. Biomimetic hybrid scaffold was fabricated via co-spinning approach where simultaneous electrospinning of PLLCL and Collagen was mediated by polymer sacrificing agent Polyvinylpyrrolidone (PVP). Acidified aqueous solution of PVP was used to solubilize collagen without using toxic solvents for electrospinning, and then PVP was readily removed by rinsing in water. Mechanical characterizations, protein adsorption, as well as biodegradation analysis have been conducted to investigate feasibility of biomimetic hybrid scaffold for 3D cell culture applications. Electrospun biomimetic hybrid scaffold, which has 3D-network structure with 300-450 nm fiber diameters, was found to be maximizing cell adhesion through assisting NIH 3T3 mouse fibroblast cells. 3D cell culture studies confirmed that presence of collagen in biomimetic hybrid scaffold have created a major impact on cell proliferation compared to conventional 2D systems on long-term, also cell viability increased with the increasing amount of collagen.


Asunto(s)
Materiales Biomiméticos/química , Colágeno/química , Electricidad , Poliésteres/química , Andamios del Tejido/química , Adsorción , Animales , Materiales Biomiméticos/metabolismo , Materiales Biomiméticos/toxicidad , Supervivencia Celular/efectos de los fármacos , Matriz Extracelular/metabolismo , Fenómenos Mecánicos , Ratones , Células 3T3 NIH , Poliésteres/metabolismo , Poliésteres/toxicidad , Albúmina Sérica Bovina/química
15.
Biomater Sci ; 6(7): 1996, 2018 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-29901665

RESUMEN

Correction for 'Scaffold-free three-dimensional cell culturing using magnetic levitation' by Esra Türker et al., Biomater. Sci., 2018, DOI: 10.1039/c8bm00122g.

16.
Biomater Sci ; 6(7): 1745-1753, 2018 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-29700506

RESUMEN

Three-dimensional (3D) cell culture has emerged as a pioneering methodology and is increasingly utilized for tissue engineering, 3D bioprinting, cancer model studies and drug development studies. The 3D cell culture methodology provides artificial and functional cellular constructs serving as a modular playground prior to animal model studies, which saves substantial efforts, time and experimental costs. The major drawback of current 3D cell culture methods is their dependency on biocompatible scaffolds, which often require tedious syntheses and fabrication steps. Herein, we report an easy-to-use methodology for the formation of scaffold-free 3D cell culture and cellular assembly via magnetic levitation in the presence of paramagnetic agents. To paramagnetize the cell culture environment, three different Gadolinium(iii) chelates were utilized, which led to levitation and assembly of cells at a certain levitation height. The assembly and close interaction of cells at the levitation height where the magnetic force was equilibrated with gravitational force triggered the formation of complex 3D cellular structures. It was shown that Gd(iii) chelates provided an optimal levitation that induced intercellular interactions in scaffold-free format without compromising cell viability. NIH 3T3 mouse fibroblasts and HCC827 non-small-cell lung cancer cells were evaluated via the magnetic levitation system, and the formation of 3D cell culture models was validated for both cell lines. Hereby, the developed magnetic levitation system holds promises for complex cellular assemblies and 3D cell culture studies.


Asunto(s)
Técnicas de Cultivo de Célula/instrumentación , Células Epiteliales/efectos de los fármacos , Gadolinio DTPA/farmacología , Compuestos Heterocíclicos/farmacología , Compuestos Organometálicos/farmacología , Ingeniería de Tejidos/métodos , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Células Epiteliales/citología , Células Epiteliales/fisiología , Gadolinio DTPA/química , Gravitación , Compuestos Heterocíclicos/química , Humanos , Campos Magnéticos , Imanes , Ratones , Células 3T3 NIH , Compuestos Organometálicos/química
17.
ACS Biomater Sci Eng ; 4(3): 787-799, 2018 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-33418764

RESUMEN

The magnetic levitation technique has been utilized to orientate and manipulate objects both in two dimensions (2D) and three dimensions (3D) to form complex structures by combining various types of materials. Magnetic manipulation holds great promise for several applications such as self-assembly of soft substances and biological building blocks, manipulated tissue engineering, as well as cell or biological molecule sorting for diagnostic purposes. Recent studies are proving the potential of magnetic levitation as an emerging tool in biotechnology. This review outlines the advances of newly developing magnetic levitation technology on biological applications in aqueous environment from the biotechnology perspective.

18.
Otol Neurotol ; 38(10): 1411-1414, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29076927

RESUMEN

OBJECTIVES: To investigate the relationship between sudden sensorineural hearing loss (SSNHL) and migraine, assess the prevalence of migraine in patients with idiopathic SSNHL, and determine a possible common vascular etiopathogenesis for migraine and SSNHL. STUDY DESIGN: Prospective cohort study. SETTING: Tertiary referral center. PATIENTS: This study initially assessed 178 SSNHL cases obtained from the Head and Neck Surgery Clinic patient database at a tertiary hospital in Turkey between January 2011 and March 2016. Ultimately, a total of 61 idiopathic SSNHL patients participated in the present study. INTERVENTIONS:: Diagnostic. MAIN OUTCOME MEASURES: Cases with inflammation in the middle or inner ear; a retro cochlear tumor; autoimmune, infectious, functional, metabolic, neoplastic, traumatic, toxic, or vascular causes; Meniere's disease; otosclerosis; multiple sclerosis; and/or cerebrovascular diseases were excluded. RESULTS: Of the 61 idiopathic SSHNL patients, 34 were women (55.74%); and 24 (39.34%) had migraine, according to the criteria of the International Headache Society (IHS). The mean age of the migraine patients (Group 1) was 43.83 ±â€Š13.16 years, and that of those without migraine (Group 2) was 51.05 ±â€Š16.49 years. The groups did not significantly differ in terms of age, sex, or SSNHL recovery rates according to the Siegel criteria (p > 0.05). Ten of the migraine patients experienced visual aura, and the recovery rates of this group were higher. Additionally, the rate of total hearing loss was lower in Group 1 (n = 3, 12.5%) than in Group 2 (n = 10, 27%). CONCLUSION: SSNHL patients had a higher prevalence of migraine. Although those with migraine had higher recovery rates, the differences were not statistically significant.


Asunto(s)
Pérdida Auditiva Sensorineural/complicaciones , Pérdida Auditiva Súbita/complicaciones , Trastornos Migrañosos/epidemiología , Adulto , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
19.
Ear Nose Throat J ; 96(4-5): E1-E7, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28489237

RESUMEN

We conducted a prospective study to analyze the medially displaced courses of the common carotid artery (CCA) and the cervical segment of the internal carotid artery (ICA) in patients who were diagnosed with a pulsatile mass on nasopharyngolaryngoscopy and by clinicoradiologic findings. Our study group was made up of 62 patients-40 women and 22 men, aged 30 to 88 years (mean: 63.7)-who presented with a submucosal pseudomass or a bulging mass on the pharyngeal wall with obvious pulsation. For comparison purposes, we recruited a control group of 62 consecutively presenting patients who had been admitted to our Neurology Department with acute severe headache and who had undergone CT angiography based on a suspicion of an aneurysm or a vertebral or carotid artery dissection. A medially displaced carotid artery was identified in all patients in the study group. Two main course abnormalities were observed: (1) a pharyngeal superficial placement (PSP), consisting of a bulging or placement immediately adjacent to the naso-orohypopharyngeal lumen, and (2) a retropharyngeal midline placement (RMP), which entailed medialization of the carotid arteries to the midline. A PSP was observed in 11 patients, an RMP was found in 17 patients, and both were seen in 34 patients. The distance from the aberrant carotid artery to the pharyngeal wall and to the retropharyngeal midline of the retropharynx was measured at four levels: nasopharyngeal, retropalatal, retroglossal, and retroepiglottic in both groups. The mean distance was significantly shorter in the study group than in the control group at all four levels (p < 0.002). We conclude that the most likely diagnosis of a pulsatile mass detected on nasopharyngolaryngoscopy is an aberrant CCA or cervical ICA.


Asunto(s)
Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Arteria Carótida Común/diagnóstico por imagen , Arteria Carótida Interna/diagnóstico por imagen , Angiografía por Tomografía Computarizada , Angiografía por Resonancia Magnética , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades de las Arterias Carótidas/complicaciones , Arteria Carótida Común/patología , Arteria Carótida Interna/patología , Medios de Contraste , Trastornos de Deglución/etiología , Mareo/etiología , Endoscopía , Femenino , Pérdida Auditiva/etiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensación , Trastornos del Sueño-Vigilia/etiología , Acúfeno/etiología
20.
Neurol Sci ; 38(4): 605-610, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28083759

RESUMEN

Carpal tunnel syndrome (CTS), majority of cases are considered to be idiopathic, is the most commonly encountered peripheral neuropathy causing disability. We asserted that thick and big hands may more prone to idiopathic CTS (ICTS) than others. The study included 165 subjects admitted to our electrophysiology lab with pre-diagnosis of CTS between May 2014 and April 2015. Eighty-five of the subjects were diagnosed as ICTS. The parameters analyzed were: age, gender, occupation, BMI, hand dominance, grade of ICTS, wrist circumference, proximal/distal width of palm, hand/palm length, hand volume and palm length/proximal palm width. Female gender was significantly higher in both groups. The mean age of study group was 44.02 ± 9.11 years, and control group was 41.25 ± 9.94 years. BMI, wrist circumference and hand volume were significantly higher in the study group (p < 0.05). However, palm length/prox.palm width ratio was higher in the control group (p = 0.00). There were also significant differences among CTS groups in terms of age (p = 0.001). Mean age was higher in severe CTS group. Female gender, older age and high BMI are risk factors for ICTS. Higher hand volume, wrist circumference and lower palm length/prox. palm width ratio can also be anthropometric risk factors. Large hand volumes, big and coarse hands are more prone to ICTS.


Asunto(s)
Síndrome del Túnel Carpiano/patología , Mano/patología , Adulto , Factores de Edad , Índice de Masa Corporal , Síndrome del Túnel Carpiano/fisiopatología , Femenino , Humanos , Modelos Logísticos , Masculino , Conducción Nerviosa , Tamaño de los Órganos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Muñeca/patología
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