scholarly journals Advances in Biosensors Technology for Detection and Characterization of Extracellular Vesicles

Sensors ◽  
2021 ◽  
Vol 21 (22) ◽  
pp. 7645
Author(s):  
Saif Mohammad Ishraq Bari ◽  
Faria Hossain ◽  
Gergana Nestorova
Keyword(s):  
Signal To Noise Ratio ◽  
Biological Fluids ◽  
Point Of Care ◽  
Invasive Disease ◽  
Size Exclusion ◽  
Clinical Settings ◽  
Cell Of Origin ◽  
Accurate Identification ◽  
Isolation And Characterization ◽  
On Chip

Exosomes are extracellular vehicles (EVs) that encapsulate genomic and proteomic material from the cell of origin that can be used as biomarkers for non-invasive disease diagnostics in point of care settings. The efficient and accurate detection, quantification, and molecular profiling of exosomes are crucial for the accurate identification of disease biomarkers. Conventional isolation methods, while well-established, provide the co-purification of proteins and other types of EVs. Exosome purification, characterization, and OMICS analysis are performed separately, which increases the complexity, duration, and cost of the process. Due to these constraints, the point-of-care and personalized analysis of exosomes are limited in clinical settings. Lab-on-a-chip biosensing has enabled the integration of isolation and characterization processes in a single platform. The presented review discusses recent advancements in biosensing technology for the separation and detection of exosomes. Fluorescent, colorimetric, electrochemical, magnetic, and surface plasmon resonance technologies have been developed for the quantification of exosomes in biological fluids. Size-exclusion filtration, immunoaffinity, electroactive, and acoustic-fluid-based technologies were successfully applied for the on-chip isolation of exosomes. The advancement of biosensing technology for the detection of exosomes provides better sensitivity and a reduced signal-to-noise ratio. The key challenge for the integration of clinical settings remains the lack of capabilities for on-chip genomic and proteomic analysis.

scholarly journals Development, Validation and Application of a UHPLC-MS Method for the Quantification of Chios Mastic Gum Triterpenoids in Human Plasma

Planta Medica ◽  
2021 ◽  
Author(s):  
Vincent Brieudes ◽  
Eleni V. Mikropoulou ◽  
Errikos Kallergis ◽  
Andriana C. Kaliora ◽  
Efstathia Papada ◽  
...  
Keyword(s):  
Human Plasma ◽  
Biological Fluids ◽  
Structural Characteristics ◽  
Biological Properties ◽  
Lipid Lowering ◽  
High Yield ◽  
Limit Of Quantification ◽  
Isolation And Characterization ◽  
Starting Point ◽  
Chios Mastic Gum

AbstractChios mastic gum is the resinous secretion obtained from the barks of the shrub Pistacia lentiscus var. Chia, which is endemic to the Greek island of Chios. Since antiquity, Chios mastic gum has found several uses as a phytotherapeutic remedy, primarily for the treatment of gastrointestinal disorders while recently, Chios mastic gum was also recognized by EMA as an herbal medicinal product with specific indications. Chios mastic gumʼs biological properties are attributed to triterpenes which comprise the major chemical group (approx. 70%) and notably isomasticadienonic acid and masticadienonic acid. However, due to their structural characteristics, the isolation thereof in high yield and purity is challenging and since they are not commercially available, pharmacological studies aiming to assess their biological properties are limited. In the present work, masticʼs phytochemical investigation by UPLC-HRMS is followed by the isolation and characterization of isomasticadienonic acid and masticadienonic acid to be used as analytical standards for their accurate and reliable quantification in human plasma. A UHPLC-tQ-MS method that was developed and validated (in terms of specificity, linearity, limit of quantification, accuracy and precision), for the direct quantification of the targeted compounds in the low ng/mL range of concentration, was subsequently implemented on plasma samples of healthy volunteers thus demonstrating its fitness for purpose. The results presented herein might provide insight to the understanding of this traditional natural product consumed notably for its anti-inflammatory, antioxidant and lipid lowering properties. Moreover, this method might serve as a starting point for any study aiming to monitor bioactive triterpenes in biological fluids.

Prussian blue-doped PAMAM dendrimer nanospheres for electrochemical immunoassay of human plasma cardiac troponin I without enzymatic amplification

2021 ◽  
Author(s):  
Fangfang Ma ◽  
Gaoshun Ge ◽  
Yizhen Fang ◽  
Erru Ni ◽  
Yuanyuan Su ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Cardiac Troponin ◽  
Troponin I ◽  
Biological Fluids ◽  
Pamam Dendrimer ◽  
Cardiac Troponin I ◽  
Electrochemical Immunoassay ◽  
Accurate Identification ◽  
Enzymatic Amplification ◽  
Electrochemical Immunosensing

Rapid and accurate identification of cardiac troponin I (cTnl) in biological fluids is very essential for judging acute myocardial infarction (AMI). Herein, we constructed an enzyme-free electrochemical immunosensing system for...

scholarly journals Using a Common Average Reference to Improve Cortical Neuron Recordings From Microelectrode Arrays

2009 ◽  
Vol 101 (3) ◽  
pp. 1679-1689 ◽  
Author(s):  
Kip A. Ludwig ◽  
Rachel M. Miriani ◽  
Nicholas B. Langhals ◽  
Michael D. Joseph ◽  
David J. Anderson ◽  
...  
Keyword(s):  
Signal To Noise Ratio ◽  
Reference Electrode ◽  
Sprague Dawley ◽  
Average Reference ◽  
Markov Theorem ◽  
Sprague Dawley Rats ◽  
On Chip ◽  
Mathematical Justification ◽  
Signal Sources

In this study, we propose and evaluate a technique known as common average referencing (CAR) to generate a more ideal reference electrode for microelectrode recordings. CAR is a computationally simple technique, and therefore amenable to both on-chip and real-time applications. CAR is commonly used in EEG, where it is necessary to identify small signal sources in very noisy recordings. To study the efficacy of common average referencing, we compared CAR to both referencing with a stainless steel bone-screw and a single microelectrode site. Data consisted of in vivo chronic recordings in anesthetized Sprague-Dawley rats drawn from prior studies, as well as previously unpublished data. By combining the data from multiple studies, we generated and analyzed one of the more comprehensive chronic neural recording datasets to date. Reference types were compared in terms of noise level, signal-to-noise ratio, and number of neurons recorded across days. Common average referencing was found to drastically outperform standard types of electrical referencing, reducing noise by >30%. As a result of the reduced noise floor, arrays referenced to a CAR yielded almost 60% more discernible neural units than traditional methods of electrical referencing. CAR should impart similar benefits to other microelectrode recording technologies—for example, chemical sensing—where similar differential recording concepts apply. In addition, we provide a mathematical justification for CAR using Gauss-Markov theorem and therefore help place the application of CAR into a theoretical context.

scholarly journals DEVELOPMENT OF CANCER DIAGNOSTICS AND MONITORING METHODS BASED ON ANALYSIS OF TUMOR-DERIVED EXOSOMES

2015 ◽  
Vol 14 (4) ◽  
pp. 9-18 ◽  
Author(s):  
A. V. Malek ◽  
R. B. Samsonov ◽  
A. . Chiesi
Keyword(s):  
Physiological Function ◽  
Biological Fluids ◽  
Membrane Vesicles ◽  
Cell Types ◽  
Cancer Diagnostics ◽  
Cell Of Origin ◽  
Monitoring Methods ◽  
New Methods ◽  
Methodological Aspects ◽  
Promising Source

Exosomes are small (80 - 130 nm) membrane vesicles secreted by virtually all cell types. The main physiological function of exosomes is considered to transfer substance and information from cell to cell. The biochemical composition of exosomes retains similarities with the cell of origin and reflects their endosomal biogenesis; moreover exosomes contain various signaling and regulatory molecules, components of the extracellular matrix and enzymes. Malignant transformation is associated with the activation of the exosomes secretion by cells. Cancer cell - derived exosomes are shown to play essential role in disease progression. The most significant effects of exosomes include suppression of anti-tumor immunity, stimulation of invasive growth and metastasis, the development of chemo- resistance. Tumor-derived exosomes can be detected in biological fluids, including blood. Exosomes are biochemically stable, their complex composition determines the possibility of comprehensive analysis. Thus, circulating exosomes have emerged as a promising source of cancer diagnostics material as it was demonstrated by number of studies. Although many substantial and methodological questions still remain to be addressed. This review briefly summarizes the current concepts of exosomes biology and discusses the main methodological aspects of exosomes research. Results of recent investigations aimed to develop new methods for cancer diagnosis and monitoring based on the analysis of exosomes and exosomal components are presented in great details.

scholarly journals The Application of Hand-Held Ultrasound Scanner in Teaching of Telemedicine and Rural Medicine

2014 ◽  
Vol 8 (1) ◽  
pp. 87-91 ◽  
Author(s):  
Oscar Noriega ◽  
Hoi Ho ◽  
Justin Wright
Keyword(s):  
Point Of Care ◽  
Modern Medicine ◽  
Diagnostic Instrument ◽  
Obstetrics And Gynecology ◽  
Clinical Settings ◽  
Ultrasound Images ◽  
Rural Medicine ◽  
Physical Examinations ◽  
Ultrasound Scanner

ABSTRACT Stethoscope, the symbol of modern medicine has been in place for more than 150 years. However, this reliable diagnostic instrument has started showing its age with the arrival of a newer diagnostic instrument: the hand-held ultrasound. Hand-held ultrasound is rapidly expanding in many specialties but not yet in obstetrics and gynecology. There is a paucity of literature on the application of hand-held ultrasound in obstetrics and gynecology, in contrast to a large volume of literature published by other specialties. Several studies demonstrated that medical students and residents can improve the accuracy of their physical examinations with the use of hand-held ultrasound. Similarly, physical examinations performed by hospitalists with hand-carried ultrasound are more accurate than those performed without the instrument. Advances in technology have contributed to the improvement of image quality and portability. As a result, these devices become increasingly available in many clinical settings such as point of care, telemedicine and rural medicine. The quality of ultrasound images of the hand-held scanner is inferior to those of standard laptop ultrasound. However, the hand-held ultrasound requires much less time for setup. Although there have been recommendations for training guidelines for operators of hand-held ultrasound, standards for optimal training to achieve level of competency have not been determined. How to cite this article Wright J, Noriega O, Ho H. The Application of Hand-Held Ultrasound Scanner in Teaching of Telemedicine and Rural Medicine. Donald School J Ultrasound Obstet Gynecol 2014;8(1):87-91.

Point-of-care ultrasound in a multiplace hyperbaric chamber

2021 ◽  
pp. 221-226
Author(s):  
Kirsten Hornbeak ◽  
◽  
Jay Duchnick ◽  
Anthony Medak ◽  
Peter Lindholm ◽  
...  
Keyword(s):  
Imaging Modality ◽  
Point Of Care ◽  
Electronic Devices ◽  
Point Of Care Ultrasound ◽  
Clinical Settings ◽  
Proof Of Concept ◽  
Safety Standards ◽  
Patient Assessments ◽  
Hyperbaric Environment ◽  
Hbo2 Therapy

Historically, electronic devices have been generally prohibited during hyperbaric oxygen (HBO2) therapy due to risk of fire in a pressurized, oxygen-rich environment. Point-of-care ultrasound (POCUS), however, has emerged as a useful imaging modality in diverse clinical settings. Hyperbaric chambers treating critically ill patients would benefit from the application of POCUS at pressure to make real-time patient assessments. Thus far, POCUS during HBO2 therapy has been limited due to required equipment modifications to meet safety standards. Here we demonstrate proof of concept, safety, and successful performance of an off-the-shelf handheld POCUS system (SonoSite iViz) in a clinical hyperbaric environment without need for modification.

scholarly journals Low-Fouling Substrates for Plasmonic Sensing of Circulating Biomarkers in Biological Fluids

Biosensors ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 63
Author(s):  
Elba Mauriz
Keyword(s):  
Biological Fluids ◽  
Point Of Care ◽  
Disease Onset ◽  
Screening Tools ◽  
Circulating Biomarkers ◽  
Prognostic Information ◽  
Wide Range ◽  
Biomarker Analysis ◽  
Surface Enhanced Raman ◽  
The Impact

The monitoring of biomarkers in body fluids provides valuable prognostic information regarding disease onset and progression. Most biosensing approaches use noninvasive screening tools and are conducted in order to improve early clinical diagnosis. However, biofouling of the sensing surface may disturb the quantification of circulating biomarkers in complex biological fluids. Thus, there is a great need for antifouling interfaces to be designed in order to reduce nonspecific adsorption and prevent inactivation of biological receptors and loss of sensitivity. To address these limitations and enable their application in clinical practice, a variety of plasmonic platforms have been recently developed for biomarker analysis in easily accessible biological fluids. This review presents an overview of the latest advances in the design of antifouling strategies for the detection of clinically relevant biomarkers on the basis of the characteristics of biological samples. The impact of nanoplasmonic biosensors as point-of-care devices has been examined for a wide range of biomarkers associated with cancer, inflammatory, infectious and neurodegenerative diseases. Clinical applications in readily obtainable biofluids such as blood, saliva, urine, tears and cerebrospinal and synovial fluids, covering almost the whole range of plasmonic applications, from surface plasmon resonance (SPR) to surface-enhanced Raman scattering (SERS), are also discussed.

Point-of-Care Systems for Rapid DNA Quantification in Oncology

2008 ◽  
Vol 94 (2) ◽  
pp. 216-225 ◽  
Author(s):  
Marco Bianchessi ◽  
Sarah Burgarella ◽  
Marco Cereda
Keyword(s):  
Point Of Care ◽  
Low Cost ◽  
Semiconductor Industry ◽  
Point Of Care Testing ◽  
Lab On Chip ◽  
Diagnostic Assays ◽  
Care Systems ◽  
Point Of Care Systems ◽  
The Common ◽  
On Chip

The development of new powerful applications and the improvement in fabrication techniques are promising an explosive growth in lab-on-chip use in the upcoming future. As the demand reaches significant levels, the semiconductor industry may enter in the field, bringing its capability to produce complex devices in large volumes, high quality and low cost. The lab-on-chip concept, when applied to medicine, leads to the point-of-care concept, where simple, compact and cheap instruments allow diagnostic assays to be performed quickly by untrained personnel directly at the patient's side. In this paper, some practical and economical considerations are made to support the advantages of point-of-care testing. A series of promising technologies developed by STMicroelectronics on lab-on-chips is also presented, mature enough to enter in the common medical practice. The possible use of these techniques for cancer research, diagnosis and treatment are illustrated together with the benefits offered by their implementation in point-of-care testing.

Isolation and characterization of hematopoietic progenitor/stem cells in 5q-deleted myelodysplastic syndromes: evidence for involvement at the hematopoietic stem cell level

Blood ◽  
2000 ◽  
Vol 96 (6) ◽  
pp. 2012-2021 ◽  
Author(s):  
Lars Nilsson ◽  
Ingbritt Åstrand-Grundström ◽  
Ingrid Arvidsson ◽  
Björn Jacobsson ◽  
Eva Hellström-Lindberg ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Myelodysplastic Syndromes ◽  
Large Fraction ◽  
Functional Characterization ◽  
Severe Combined Immunodeficiency ◽  
Good Prognosis ◽  
Cell Of Origin ◽  
Hematopoietic Stem ◽  
Isolation And Characterization

Abstract Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal disorders characterized by ineffective hematopoiesis and frequent progression to acute myeloid leukemia. Within MDS, 5q− syndrome constitutes a distinct clinical entity characterized by an isolated deletion of the long arm of chromosome 5 (5q−), a relatively good prognosis, and infrequent transformation to acute leukemia. The cell of origin in 5q− syndrome as well as in other 5q-deleted MDS patients has not been established, but evidence for involvement of multiple myeloid (but not lymphoid) lineages has suggested that a myeloid-restricted progenitor rather than a pluripotent (lympho-myeloid) stem cell might be the primary target in most patients. Although in 9 patients no evidence of peripheral blood T-cell and only 1 case of B-cell involvement was found, the data herein support that 5q deletions occur in hematopoietic stem cells (HSCs) with a combined lympho-myeloid potential. First, in all investigated patients a minimum of 94% of cells in the minor CD34+CD38− HSC compartment were 5q deleted as determined by fluorescence in situ hybridization. Second, in 3 of 5 patients 5q aberrations were detected in a large fraction (25% to 90%) of purified CD34+CD19+ pro-B cells. Furthermore, extensive functional characterization with regard to responsiveness to early-acting cytokines, long-term culture-initiating cells, and nonobese diabetic/severe combined immunodeficiency repopulating cells supported that MDS HSCs in 5q-deleted patients are CD34+CD38−, but inefficient at reconstituting hematopoiesis.

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