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Background: Percutaneous dilatational tracheostomy (PDT) is the most commonly performed minimally invasive intensive care unit procedure worldwide. Methods: This study evaluated the percentage of consistency between the entry site observed with fiberoptic bronchoscopy (FOB) and the prediction for the PDT level based on pre-procedural ultrasonography (USG) in PDT procedures performed using the forceps dilatation method. The effect of morphological features on intervention sites was also investigated. Complications that occurred during and after the procedure, as well as the duration, site, and quantity of the procedures, were recorded. Results: Data obtained from a total of 91 patients were analyzed. In 57 patients (62.6%), the USG-estimated tracheal puncture level was consistent with the intercartilaginous space observed by FOB, while in 34 patients (37.4%), there was a discrepancy between these two methods. According to Bland Altman, the agreement between the tracheal spaces determined by USG and FOB was close. Regression formulas for PDT procedures defining the intercartilaginous puncture level based on morphologic measurements of the patients were created. The most common complication related to PDT was cartilage fracture (17.6%), which was proven to be predicted with maximum relevance by punctured tracheal level, neck extension limitation, and procedure duration. Conclusions: In PDT procedures using the forceps dilatation method, the prediction of the PDT intervention level based on pre-procedural USG was considerably in accordance with the entry site observed by FOB. The intercartilaginous puncture level could be estimated based on morphological measurements. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The hERG (human ether-à-go-go-related gene) potassium channel has been extensively studied by both academia and industry because of its relation to inherited or drug-induced long QT syndrome (LQTS). Unpredicted hERG and drug interaction affecting channel activity is of main concern for drug discovery. Although there are several methods to test hERG and drug interaction, it is still necessary to develop some efficient and economic ways to probe hERG and drug interactions. To contribute this aim, we have developed a biomimetic lipid membrane platform into which the hERG channel can be folded. Expression and integration of the hERG channel was achieved using a cell-free (CF) expression system. The folding of hERG in the biomimetic membrane system was investigated using Surface Plasmon Enhanced Fluorescence Spectroscopy (SPFS) and Imaging Surface Plasmon Resonance (iSPR). In addition, the hERG channel folded into our biomimetic membrane platform was used for probing the channel and drug interactions through fluorescence polarization (FP) assay. Our results suggest that the biomimetic system employed is capable of detecting the interaction between hERG and different channel blockers at varied concentrations. We believe that our current approach could be applied to other membrane proteins for drug screening or other protein-related interactions. [ABSTRACT FROM AUTHOR]

Abstract: A facile method for assembly of biomimetic membranes serving as a platform for expression and insertion of membrane proteins is described. The membrane architecture was constructed in three steps: (i) assembly/printing of α-laminin peptide (P19) spacer on gold to separate solid support from the membrane architecture; (ii) covalent coupling of different lipid anchors to the P19 layer to serve as stabilizers of the inner leaflet during bilayer formation; (iii) lipid vesicle spreading to form a complete bilayer. Two different lipid membrane systems were examined and two different P19 architectures prepared by either self-assembly or μ-contact printing were tested and characterized using contact angle (CA) goniometry, surface plasmon resonance (SPR) spectroscopy and imaging surface plasmon resonance (iSPR). It is shown that surface coverage of cushion layer is significantly improved by μ-contact printing thereby facilitating bilayer formation as compared to self-assembly. To validate applicability of proposed methodology, incorporation of Cytochrome bo 3 ubiquinol oxidase (Cyt-bo 3) into biomimetic membrane was performed by in vitro expression technique which was further monitored by surface plasmon enhanced fluorescence spectroscopy (SPFS). The results showed that solid supported planar membranes, tethered by α-laminin peptide cushion layer, provide an attractive environment for membrane protein insertion and characterization. [Copyright &y& Elsevier]

• A facile methodology is developed here for easy processing of propolis with assistance of PVA as co-electrospinning agent. • Solubility based processing limitations of propolis were overcome. • Porous, nanofibrillar biomimetic architectures were obtained through co-spinning of Propolis and PVA. • Electrospun Propolis/PVA scaffold is proposed as a potential candidate for biomedical applications. This study depicts easy process of propolis by co-electrospinning without using any toxic agent for biomedical applications. To achieve this, polyvinyl alcohol was utilized as co-spinning agent to fabricate biomimetic Propolis/PVA scaffold. Here, whilst PVA was used as a supportive material to accumulate propolis in scaffold, propolis was employed to enrich biologic aspect of scaffold. This strategy overcomes challenges of propolis processing originated from solubility problems and offers easy processability of propolis in order to use in biomedical applications. Electrospun Propolis/PVA scaffolds were crosslinked with glutaraldehyde and drop-cast model was utilized as a control. Formation of porous, bead-free nanofiber architectures was confirmed through surface morphology analysis, while drop-cast model shows non-porous morphology. Wettability results confirmed both crosslinking and integration of propolis into polyvinyl alcohol scaffold moved contact angle to hydrophobic region. Presence and amount of propolis in hybrid scaffolds were validated via absorbance spectrum results. Bioactivity and biocompatibility of propolis-enriched scaffolds were analyzed through protein adsorption capacity. Obtained findings are evidence that electrospinning methodology offers easy and biosafe process of propolis. Electrospun Propolis/PVA exhibits desired properties and could be potentially utilized as scaffold for tissue engineering or as a wound dressing graft in biomedical field. [ABSTRACT FROM AUTHOR]

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. [Display omitted] [ABSTRACT FROM AUTHOR]

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. [Display omitted] [ABSTRACT FROM AUTHOR]

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. Unlabelled Image [ABSTRACT FROM AUTHOR]

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. [Display omitted] • A novel tissue-engineering scaffold was fabricated by using glucuronoxylan-based quince seed hydrogel (QSH). • QSH was characterized in terms of morphology, crosslinking and swelling capacity. • QSH scaffold exhibits high biocompatibility and cell viability. [ABSTRACT FROM AUTHOR]

Several cellular events cause permanent or transient changes in inherent magnetic and density properties of cells. Characterizing these changes in cell populations is crucial to understand cellular heterogeneity in cancer, immune response, infectious diseases, drug resistance, and evolution. Although magnetic levitation has previously been used for macroscale objects, its use in life sciences has been hindered by the inability to levitate microscale objects and by the toxicity of metal salts previously applied for levitation. Here, we use magnetic levitation principles for biological characterization and monitoring of cells and cellular events. We demonstrate that each cell type (i.e., cancer, blood, bacteria, and yeast) has a characteristic levitation profile, which we distinguish at an unprecedented resolution of 1 × 10-4 g·mL-1. We have identified unique differences in levitation and density blueprints between breast, esophageal, colorectal, and nonsmall cell lung cancer cell lines, as well as heterogeneity within these seemingly homogenous cell populations. Furthermore, we demonstrate that changes in cellular density and levitation profiles can be monitored in real time at single-cell resolution, allowing quantification of heterogeneous temporal responses of each cell to environmental stressors. These data establish density as a powerful biomarker for investigating living systems and their responses. Thereby, our method enables rapid, density-based imaging and profiling of single cells with intriguing applications, such as label-free identification and monitoring of heterogeneous biological changes under various physiological conditions, including antibiotic or cancer treatment in personalized medicine. [ABSTRACT FROM AUTHOR]

• A rapid gelating 2-isocyanatoethyl methacrylate modified gelatin is obtained. • Novel hydrogel has excellent porous morphology and swelling capacity. • The novel hydrogel can be used in bioprinting and molding processes. • The novel hydrogel bioink has excellent biocompatibility. This study describes low dose UV curable and bioprintable new bioink made of hydrogen bond donor-acceptor adaptor molecule 2-isocyanatoethyl methacrylate (NCO)modified gelatin (NCO-Gel). Our theoretical calculations demonstrate that insertion of 2-isocyanatoethyl methacrylate doubles the interaction energy (500 meV) between gelatin chains providing significant contribution in interchain condensation and self-organization as compared to methacrylic anhydride modified gelatin (GelMA). The NCO-Gel exhibits peak around 1720 cm−1 referring to bidentate hydrogen bonding between H-NCO and its counterpart O CN H. These strong interchain interactions drive chains to be packed and thereby facilitating UV crosslinking. The NCO-Gel is exhibiting a rapid, 10 s gelation process by the exposure of laser (3 W, 365 nm). The dynamic light scattering characterization also reveals that NCO-Gel has faster sol to gel transition as compared to GelMA depending on the UV curing time. The NCO-Gel was found to be more firm and mechanically strong that provides advantages in molding as well as bioprinting processes. Bioprinted NCO-Gel has shown sharp borders and stable 3D geometry as compared to GelMA ink under 10 s UV curing time. The cell viability tests confirm that NCO-Gel facilitates cell proliferation and supports cell viability. We foresee that NCO-Gel bioink formulation provides a promising opportunity when low dose UV curing and rapid printing are required. [ABSTRACT FROM AUTHOR]