scholarly journals Isolation of Cell-Free miRNA from Biological Fluids: Influencing Factors and Methods

Diagnostics ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 865
Author(s):  
Olga Bryzgunova ◽  
Maria Konoshenko ◽  
Ivan Zaporozhchenko ◽  
Alexey Yakovlev ◽  
Pavel Laktionov
Keyword(s):  
Clinical Research ◽  
Structural Properties ◽  
Influencing Factors ◽  
High Stability ◽  
Biological Fluids ◽  
Supramolecular Complexes ◽  
Clinical Settings ◽  
Downstream Analysis ◽  
Extracellular Environment

A vast wealth of recent research has seen attempts of using microRNA (miRNA) found in biological fluids in clinical research and medicine. One of the reasons behind this trend is the apparent their high stability of cell-free miRNA conferred by small size and packaging in supramolecular complexes. However, researchers in both basic and clinical settings often face the problem of selecting adequate methods to extract appropriate quality miRNA preparations for use in specific downstream analysis pipelines. This review outlines the variety of different methods of miRNA isolation from biofluids and examines the key determinants of their efficiency, including, but not limited to, the structural properties of miRNA and factors defining their stability in the extracellular environment.

Separation of Extracellular Vesicles by DNA-Directed Immunocapturing Followed by Enzymatic Release

2020 ◽  
Author(s):  
Dario Brambilla ◽  
Laura Sola ◽  
Elisa Chiodi ◽  
Natasa Zarovni ◽  
Diogo Fortunato ◽  
...  
Keyword(s):  
Cell Culture ◽  
Extracellular Vesicles ◽  
Culture Media ◽  
Biological Fluids ◽  
Imaging Techniques ◽  
Cell Communication ◽  
Disease Diagnosis ◽  
Cell Culture Supernatant ◽  
Transmission Electron ◽  
Downstream Analysis

Extracellular vesicles (EVs) have attracted great interest among researchers due to their role in cell-cell communication, disease diagnosis, and drug delivery. In spite of their potential in the medical field, there is no consensus on the best method for separating microvesicles from cell culture supernatant and complex biological fluids. Obtaining a good recovery yield and preserving physical characteristics is critical for the diagnostic and therapeutic use of EVs. The separation is made complex by the fact that blood and cell culture media, contain a large number of nanoparticles in the same size range. Methods that exploit immunoaffinity capture provide high purity samples and overcome the issues of currently used separation methods. However, the release of captured nanovesicles requires harsh conditions that hinder their use in certain types of downstream analysis. Herein, a novel capture and release approach for small extracellular vesicles (sEVs), based on DNAdirected immobilization of antiCD63 antibody is presented. The flexible DNAlinker increases the capture efficiency and allows releasing of EVs by exploiting the endonucleasic activity of DNAse I. This separation protocol works under mild conditions, enabling the release of intact vesicles that can be successfully analyzed by imaging techniques. In this article sEVs recovered from plasma were characterized by established techniques for EVs analysis including nanoparticle tracking and transmission electron microscopy.<br>

Influence of extracellular environment on the motility and structural properties of spermatozoa collected from hormonally stimulated Panamanian Golden Frog (Atelopus zeteki)

2018 ◽  
Vol 108 ◽  
pp. 153-160 ◽  
Author(s):  
Gina Della Togna ◽  
Brian Gratwicke ◽  
Matthew Evans ◽  
Lauren Augustine ◽  
Han Chia ◽  
...  
Keyword(s):  
Structural Properties ◽  
Extracellular Environment

scholarly journals Immuno-Acoustic Sorting of Disease-Specific Extracellular Vesicles by Acoustophoretic Force

Micromachines ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1534
Author(s):  
Junyuan Liu ◽  
Yuxin Qu ◽  
Han Wang
Keyword(s):  
Extracellular Vesicles ◽  
Processing Time ◽  
Life Science ◽  
Biological Fluids ◽  
Label Free ◽  
Her2 Positive ◽  
Diagnosis And Prognosis ◽  
Efficient Recovery ◽  
Downstream Analysis ◽  
Disease Specific

Methods for the isolation and analysis of extracellular vesicles (EVs) have been extensively explored in the field of life science and in clinical diagnosis in recent years. The separation and efficient recovery of high-purity target EVs from biological samples are important prerequisites in the study of EVs. So far, commonly used methods of EV separation include ultracentrifugation, filtration, solvent precipitation and immunoaffinity capturing. However, these methods suffer from long processing time, EV damage and low enrichment efficiency. The use of acoustophoretic force facilitates the non-contact label-free manipulation of cells based on their size and compressibility but lacks specificity. Additionally, the acoustophoretic force exerted on sub-micron substances is normally weak and insufficient for separation. Here we present a novel immuno-acoustic sorting technology, where biological substances such as EVs, viruses, and biomolecules, can be specifically captured by antibody/receptor coated microparticles through immunoaffinity, and manipulated by an acoustophoretic force exerted on the microparticles. Using immuno-acoustic sorting technology, we successfully separated and purified HER2-positive EVs for further downstream analysis. This method holds great potential in isolating and purifying specific targets such as disease-related EVs from biological fluids and opens new possibilities for the EV-based early diagnosis and prognosis of diseases.

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 Biomarkers in Mild Stages of Alzheimer’s disease: Utility in clinical practice and their relation with nutritional and lifestyle factors

2016 ◽  
Vol 6 (10) ◽  
pp. 627
Author(s):  
Carol Dillon ◽  
Patricio Pérez Leguizamon ◽  
Silvina Heisecke ◽  
Diego M. Castro ◽  
Jorge Lopez Camelo ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Clinical Trials ◽  
Clinical Practice ◽  
Clinical Research ◽  
Lifestyle Factors ◽  
Clinical Settings ◽  
Treatment Methods ◽  
Primary Endpoints ◽  
Alzheimer’S Disease Dementia

Background: The use of biomarkers in basic and clinical research as well as in clinical practice has become so common that their presence as primary endpoints in clinical trials is now accepted. A biomarker refers to a broad subcategory of medical signs. The aims of this article are to consider the of use biomarkers in Mild stages of Alzheimer’s disease (AD) in research and clinical settings, in addition to defining their utility in clinical practice relating this with nutritional and lifestyle factors as possible treatment. Methods: We searched MEDLINE, PubMed, and AgeLine databases using different keywords.Conclusions: A summary of the utility of biomarkers in AD and nutritional and lifestyle factors used as treatment in mild stages are described.Key words: Biomarkers, Alzheimer’s disease, Dementia, Utility, Clinical practice, Nutritional

scholarly journals Latent-Based Imputation of Laboratory Measures from Electronic Health Records: Case for Complex Diseases

2018 ◽  
Author(s):  
V. Abedi ◽  
M.K. Shivakumar ◽  
P. Lu ◽  
R. Hontecillas ◽  
A. Leber ◽  
...  
Keyword(s):  
Electronic Health Records ◽  
Input Data ◽  
Clinical Settings ◽  
Complex Phenotype ◽  
Future Time ◽  
Health Records ◽  
Inflammatory Bowel ◽  
Electronic Health ◽  
Unclear Etiology ◽  
Downstream Analysis

AbstractImputation is a key step in Electronic Health Records-mining as it can significantly affect the conclusions derived from the downstream analysis. There are three main categories that explain the missingness in clinical settings–incompleteness, inconsistency, and inaccuracy–and these can capture a variety of situations: the patient did not seek treatment, the health care provider did not enter the information, etc. We used EHR data from patients diagnosed with Inflammatory Bowel Disease from Geisinger Health System to design a novel imputation that focuses on a complex phenotype. Our approach is based on latent-based analysis integrated with clustering to group patients based on their comorbidities before imputation. IBD is a chronic illness of unclear etiology and without a complete cure. We have taken advantage of the complexity of IBD to pre-process the EHR data of 10,498 IBD patients and show that imputation can be improved using shared latent comorbidities. The R code and sample simulated input data will be available at a future time.

scholarly journals Limitations of Deep Learning Attention Mechanisms in Clinical Research: Empirical Case Study Based on the Korean Diabetic Disease Setting (Preprint)

2020 ◽  
Author(s):  
Junetae Kim ◽  
Sangwon Lee ◽  
Eugene Hwang ◽  
Kwang Sun Ryu ◽  
Hanseok Jeong ◽  
...  
Keyword(s):  
Deep Learning ◽  
Clinical Research ◽  
Degrees Of Freedom ◽  
Empirical Studies ◽  
Variable Importance ◽  
Prediction Performance ◽  
Attention Mechanism ◽  
Clinical Settings ◽  
Basic Concepts

BACKGROUND Despite excellent prediction performance, noninterpretability has undermined the value of applying deep-learning algorithms in clinical practice. To overcome this limitation, attention mechanism has been introduced to clinical research as an explanatory modeling method. However, potential limitations of using this attractive method have not been clarified to clinical researchers. Furthermore, there has been a lack of introductory information explaining attention mechanisms to clinical researchers. OBJECTIVE The aim of this study was to introduce the basic concepts and design approaches of attention mechanisms. In addition, we aimed to empirically assess the potential limitations of current attention mechanisms in terms of prediction and interpretability performance. METHODS First, the basic concepts and several key considerations regarding attention mechanisms were identified. Second, four approaches to attention mechanisms were suggested according to a two-dimensional framework based on the degrees of freedom and uncertainty awareness. Third, the prediction performance, probability reliability, concentration of variable importance, consistency of attention results, and generalizability of attention results to conventional statistics were assessed in the diabetic classification modeling setting. Fourth, the potential limitations of attention mechanisms were considered. RESULTS Prediction performance was very high for all models. Probability reliability was high in models with uncertainty awareness. Variable importance was concentrated in several variables when uncertainty awareness was not considered. The consistency of attention results was high when uncertainty awareness was considered. The generalizability of attention results to conventional statistics was poor regardless of the modeling approach. CONCLUSIONS The attention mechanism is an attractive technique with potential to be very promising in the future. However, it may not yet be desirable to rely on this method to assess variable importance in clinical settings. Therefore, along with theoretical studies enhancing attention mechanisms, more empirical studies investigating potential limitations should be encouraged.

Ultrasonic technique for the investigation of structural properties of biological fluids

1999 ◽  
Vol 105 (2) ◽  
pp. 1369-1370 ◽  
Author(s):  
Algirdas Voleišis ◽  
Rymantas J. Kažys ◽  
Liudas Mažeika ◽  
Reimondas Šliteris ◽  
Birutė Voleišienė
Keyword(s):  
Structural Properties ◽  
Biological Fluids ◽  
Ultrasonic Technique

scholarly journals Clinical research in an academic psychiatry department: some general principles and case studies

2017 ◽  
Vol 25 (6) ◽  
pp. 596-599 ◽  
Author(s):  
Philip Keightley ◽  
Paul Maguire ◽  
Rebecca E Reay ◽  
Jeffrey C Cubis ◽  
Peggy Craigie ◽  
...  
Keyword(s):  
Academic Psychiatry ◽  
Clinical Research ◽  
Medical School ◽  
Case Studies ◽  
Collaborative Research ◽  
Clinical Settings ◽  
Psychiatry Department ◽  
Protected Time ◽  
National University ◽  
New Research

Objective: This paper gives guidance for developing collaborative clinical research within an academic psychiatry department. Methods: We describe the experience at the Australian National University Medical School, and present three case studies. Results: The results reveal that general principles include, but are not limited to, intellectual curiosity, mentorship, collaboration and protected time. Conclusions: We conclude that a particular strength of a new research department at a medical school may be close collaborative research within clinical settings.

Sign in / Sign up

Export Citation Format

Share Document