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Plasmonic sensor platforms are designed for rapid, label-free, and real-time detection and they excel as the next generation biosensors. However, current methods such as Surface Plasmon Resonance require expertise and well-equipped laboratory facilities. Simpler methods such as Localized Surface Plasmon Resonance (LSPR) overcome those limitations, though they lack sensitivity. Hence, sensitivity enhancement plays a crucial role in the future of plasmonic sensor platforms. Herein, a refractive index (RI) sensitivity enhancement methodology is reported utilizing growth of gold nanoparticles (GNPs) on solid support and it is backed up with artificial neural network (ANN) analysis. Sensor platform fabrication was initiated with GNP immobilization onto solid support; immobilized GNPs were then used as seeds for chrono-spectral growth, which was carried out using NH2OH at varied incubation times. The response to RI change of the platform was investigated with varied concentrations of sucrose and ethanol. The detection of bacteria E.coli BL21 was carried out for validation as a model microorganism and results showed that detection was possible at 102 CFU/ml. The data acquired by spectrophotometric measurements were analyzed by ANN and bacteria classification with percentage error rates near 0% was achieved. The proposed LSPR-based, label-free sensor application proved that the developed methodology promises utile sensitivity enhancement potential for similar sensor platforms.

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]

Abstract Magnetic levitation though negative magnetophoresis is a novel technology to simulate weightlessness and has recently found applications in material and biological sciences. Yet little is known about the ability of the magnetic levitation system to facilitate biofabrication of in situ three dimensional (3D) cellular structures. Here, we optimized a magnetic levitation though negative magnetophoresis protocol appropriate for long term levitated cell culture and developed an in situ 3D cellular assembly model with controlled cluster size and cellular pattern under simulated weightlessness. The developed strategy outlines a potential basis for the study of weightlessness on 3D living structures and with the opportunity for real-time imaging that is not possible with current ground-based simulated weightlessness techniques. The low-cost technique presented here may offer a wide range of biomedical applications in several research fields, including mechanobiology, drug discovery and developmental biology.

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]

Background: The aim of this study is to reveal the relationship between end-tidal CO2 (EtCO2) 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, EtCO2, 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 EtCO2 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 EtCO2 values between mRS-1 (P =0.03) and mRS-2 (P =0.04). A negative moderate correlation was found between EtCO2 and mRS-2 (r =−0.410; P =0.006). The correlation between EtCO2 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 EtCO2 value measured at the time of admission is lower in the group with high mRS at both admission and discharge. [ABSTRACT FROM AUTHOR]

The objective of this work is generation of propolis/polyvinyl alcohol (PVA) scaffold by electrospinning for 3D cell culture. Here, PVA used as co‐spinning agent since propolis alone cannot be easily processed by electrospinning methodology. Propolis takes charge in maximizing biological aspect of scaffold to facilitate cell attachment and proliferation. Morphological analysis showed size of the electrospun nanofibers varied between 172–523 nm and 345–687 nm in diameter, for non‐crosslinked and crosslinked scaffolds, respectively. Incorporation of propolis resulted in desired surface properties of hybrid matrix, where hybrid scaffolds highly favored protein adsorption. To examine cell compatibility, NIH‐3T3 and HeLa cells were seeded on propolis/PVA hybrid scaffold. Results confirmed that integration of propolis supported cell adhesion and cell proliferation. Also, results indicated electrospun propolis/PVA hybrid scaffold provide suitable microenvironment for cell culturing. Therefore, developed hybrid scaffold could be considered as potential candidate for 3D cell culture and tissue engineering. [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]

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]

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]

• 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]