scholarly journals Recent Progress in Nanomaterials Modified Electrochemical Biosensors for the Detection of MicroRNA

Micromachines ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1409
Author(s):  
Sze Shin Low ◽  
Daizong Ji ◽  
Wai Siong Chai ◽  
Jingjing Liu ◽  
Kuan Shiong Khoo ◽  
...  
Keyword(s):  
Electrochemical Biosensor ◽  
Sequence Similarity ◽  
Low Cost ◽  
High Specificity ◽  
Disease Diagnosis ◽  
Electrochemical Biosensors ◽  
High Sequence Similarity ◽  
Aberrant Expression ◽  
Specificity And Sensitivity ◽  
Different Types

MicroRNAs (miRNAs) are important non-coding, single-stranded RNAs possessing crucial regulating roles in human body. Therefore, miRNAs have received extensive attention from various disciplines as the aberrant expression of miRNAs are tightly related to different types of diseases. Furthermore, the exceptional stability of miRNAs has presented them as biomarker with high specificity and sensitivity. However, small size, high sequence similarity, low abundance of miRNAs impose difficulty in their detection. Hence, it is of utmost importance to develop accurate and sensitive method for miRNA biosensing. Electrochemical biosensors have been demonstrated as promising solution for miRNA detection as they are highly sensitive, facile, and low-cost with ease of miniaturization. The incorporation of nanomaterials to electrochemical biosensor offers excellent prospects for converting biological recognition events to electronic signal for the development of biosensing platform with desired sensing properties due to their unique properties. This review introduces the signal amplification strategies employed in miRNA electrochemical biosensor and presents the feasibility of different strategies. The recent advances in nanomaterial-based electrochemical biosensor for the detection of miRNA were also discussed and summarized based on different types of miRNAs, opening new approaches in biological analysis and early disease diagnosis. Lastly, the challenges and future prospects are discussed.

scholarly journals Efficient CRISPR/Cas9 mediated Pooled-sgRNAs assembly accelerates targeting multiple genes related to male sterility in cotton

Plant Methods ◽  
2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Mohamed Ramadan ◽  
Muna Alariqi ◽  
Yizan Ma ◽  
Yanlong Li ◽  
Zhenping Liu ◽  
...  
Keyword(s):  
Genetic Transformation ◽  
Sequence Similarity ◽  
High Specificity ◽  
Transformation Method ◽  
High Sequence Similarity ◽  
Single Experiment ◽  
Next Generation Sequencing Technology ◽  
Cotton Transformation ◽  
Assembly Method ◽  
Multiple Genes

Abstract Background Upland cotton (Gossypium hirsutum), harboring a complex allotetraploid genome, consists of A and D sub-genomes. Every gene has multiple copies with high sequence similarity that makes genetic, genomic and functional analyses extremely challenging. The recent accessibility of CRISPR/Cas9 tool provides the ability to modify targeted locus efficiently in various complicated plant genomes. However, current cotton transformation method targeting one gene requires a complicated, long and laborious regeneration process. Hence, optimizing strategy that targeting multiple genes is of great value in cotton functional genomics and genetic engineering. Results To target multiple genes in a single experiment, 112 plant development-related genes were knocked out via optimized CRISPR/Cas9 system. We optimized the key steps of pooled sgRNAs assembly method by which 116 sgRNAs pooled together into 4 groups (each group consisted of 29 sgRNAs). Each group of sgRNAs was compiled in one PCR reaction which subsequently went through one round of vector construction, transformation, sgRNAs identification and also one round of genetic transformation. Through the genetic transformation mediated Agrobacterium, we successfully generated more than 800 plants. For mutants identification, Next Generation Sequencing technology has been used and results showed that all generated plants were positive and all targeted genes were covered. Interestingly, among all the transgenic plants, 85% harbored a single sgRNA insertion, 9% two insertions, 3% three different sgRNAs insertions, 2.5% mutated sgRNAs. These plants with different targeted sgRNAs exhibited numerous combinations of phenotypes in plant flowering tissues. Conclusion All targeted genes were successfully edited with high specificity. Our pooled sgRNAs assembly offers a simple, fast and efficient method/strategy to target multiple genes in one time and surely accelerated the study of genes function in cotton.

scholarly journals Cytohistopathological Study of Salivary Gland Lesions in Bundelkhand Region, Uttar Pradesh, India

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Anita Omhare ◽  
Sanjeev Kumar Singh ◽  
Jitendra Singh Nigam ◽  
Ankit Sharma
Keyword(s):  
Salivary Gland ◽  
Low Cost ◽  
Uttar Pradesh ◽  
Diagnostic Technique ◽  
High Specificity ◽  
Turnaround Time ◽  
Malignant Tumours ◽  
Female Ratio ◽  
Specificity And Sensitivity ◽  
Benign Tumours

Background. FNAC is a useful method for evaluating suspicious salivary glands lesions due to its low cost, minimum morbidity, rapid turnaround time, high specificity, and sensitivity. Aim. To know the frequency of the salivary gland lesions and cytohistological correlation in the Jhansi region, Uttar Pradesh, India. Material and Methods. In present study 124 cases were included and cytohistological correlation was made in 86 cases only. FNA was performed by using a 23/24-gauge needle without local anaesthesia. Air dried and 95% ethyl alcohol fixed wet smears were stained with Giemsa stain and Papanicolaou stain, respectively. Paraffin embedded tissue sections were stained with Haematoxylin and Eosin. Results. Parotid gland was the most commonly involved salivary gland. The commonest age group was 20 to 29 years, 30 to 39 years, and 60 to 69 years for nonneoplastic lesions, benign tumours, and malignant tumours, respectively. The overall male to female ratio was 1.17 : 1. The diagnostic accuracy of FNAC was 100%, 93.3%, and 88.2% for nonneoplastic lesions, benign tumours, and malignant tumours, respectively. Conclusion. The high accuracy, sensitivity, and specificity of FNAC confirm that preoperative cytology is a useful, quick, reliable diagnostic technique for rapid diagnosis and suitable for developing countries.

scholarly journals In-house ELISA method to analyze anti-Trypanosoma cruzi IgG reactivity for differential diagnosis and evaluation of Chagas disease morbidity

2012 ◽  
Vol 45 (1) ◽  
pp. 35-44 ◽  
Author(s):  
Lilian da Silva Santos ◽  
Rosália Morais Torres ◽  
Girley Francisco Machado-de-Assis ◽  
Maria Terezinha Bahia ◽  
Helen Rodrigues Martins ◽  
...  
Keyword(s):  
Differential Diagnosis ◽  
Chagas Disease ◽  
Clinical Status ◽  
High Specificity ◽  
Disease Diagnosis ◽  
Cross Reactivity ◽  
Serological Method ◽  
Serum Dilution ◽  
Specificity And Sensitivity ◽  
American Tegumentary Leishmaniasis

INTRODUCTION: The goal was to develop an in-house serological method with high specificity and sensitivity for diagnosis and monitoring of Chagas disease morbidity. METHODS: With this purpose, the reactivities of anti-T. cruzi IgG and subclasses were tested in successive serum dilutions of patients from Berilo municipality, Jequitinhonha Valley, Minas Gerais, Brazil. The performance of the in-house ELISA was also evaluated in samples from other relevant infectious diseases, including HIV, hepatitis C (HCV), syphilis (SYP), visceral leishmaniasis (VL), and American tegumentary leishmaniasis (ATL), and noninfected controls (NI). Further analysis was performed to evaluate the applicability of this in-house methodology for monitoring Chagas disease morbidity into three groups of patients: indeterminate (IND), cardiac (CARD), and digestive/mixed (DIG/Mix), based on their clinical status. RESULTS: The analysis of total IgG reactivity at serum dilution 1:40 was an excellent approach to Chagas disease diagnosis (100% sensitivity and specificity). The analysis of IgG subclasses showed cross-reactivity, mainly with NI, VL, and ATL, at all selected serum dilutions. Based on the data analysis, the IND group displayed higher IgG3 levels and the DIG/Mix group presented higher levels of total IgG as compared with the IND and CARD groups. CONCLUSIONS: These findings demonstrated that methodology presents promising applicability in the analysis of anti-T. cruzi IgG reactivity for the differential diagnosis and evaluation of Chagas disease morbidity.

scholarly journals Neurovascular Unit as a Source of Ischemic Stroke Biomarkers—Limitations of Experimental Studies and Perspectives for Clinical Application

2019 ◽  
Vol 11 (4) ◽  
pp. 553-579 ◽  
Author(s):  
Aleksandra Steliga ◽  
Przemysław Kowiański ◽  
Ewelina Czuba ◽  
Monika Waśkow ◽  
Janusz Moryś ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Brain Damage ◽  
Neurovascular Unit ◽  
Experimental Studies ◽  
High Specificity ◽  
Neurological Status ◽  
Developed Countries ◽  
Cerebral Stroke ◽  
Specificity And Sensitivity ◽  
Different Types

Abstract Cerebral stroke, which is one of the most frequent causes of mortality and leading cause of disability in developed countries, often leads to devastating and irreversible brain damage. Neurological and neuroradiological diagnosis of stroke, especially in its acute phase, is frequently uncertain or inconclusive. This results in difficulties in identification of patients with poor prognosis or being at high risk for complications. It also makes difficult identification of these stroke patients who could benefit from more aggressive therapies. In contrary to the cardiovascular disease, no single biomarker is available for the ischemic stroke, addressing the abovementioned issues. This justifies the need for identifying of effective diagnostic measures characterized by high specificity and sensitivity. One of the promising avenues in this area is studies on the panels of biomarkers characteristic for processes which occur in different types and phases of ischemic stroke and represent all morphological constituents of the brains’ neurovascular unit (NVU). In this review, we present the current state of knowledge concerning already-used or potentially applicable biomarkers of the ischemic stroke. We also discuss the perspectives for identification of biomarkers representative for different types and phases of the ischemic stroke, as well as for different constituents of NVU, which concentration levels correlate with extent of brain damage and patients’ neurological status. Finally, a critical analysis of perspectives on further improvement of the ischemic stroke diagnosis is presented.

scholarly journals Generation of High Affinity Anti-Peptide Polyclonal Antibodies Recognizing Goat αs1-Casein

Molecules ◽  
2020 ◽  
Vol 25 (11) ◽  
pp. 2622
Author(s):  
Aliah Zannierah Mohsin ◽  
Rashidah Sukor ◽  
Jinap Selamat ◽  
Anis Shobirin Meor Hussin ◽  
Intan Hakimah Ismail ◽  
...  
Keyword(s):  
Binding Affinity ◽  
Analytical Methods ◽  
Polyclonal Antibodies ◽  
Sequence Similarity ◽  
High Specificity ◽  
Cross Reactivity ◽  
Enzyme Linked Immunosorbent Assay ◽  
High Sequence Similarity ◽  
High Affinity

The chemical, technological and allergy properties of goat’s milk are significantly affected by the level of αs1-casein. Detection and quantification of αs1-casein requires high-specificity methods to overcome high-sequence similarity between this protein and others in the casein family. Unavailability of antibodies with high affinity and specificity towards goat αs1-casein hinders the development of immuno-based analytical methods such as enzyme-linked immunosorbent assay (ELISA) and biosensors. Here, we report the generation of polyclonal antibodies (or immunoglobulins, IgGs) raised towards goat αs1-casein N- (Nter) and C-terminal (Cter) peptide sequences. The Nter and Cter peptides of goat αs1-casein were immunized in rabbits for the generation of antisera, which were purified using protein G affinity chromatography. The binding affinity of the antisera and purified IgGs were tested and compared using indirect ELISA, where peptide-BSA conjugates and goat αs1-casein were used as the coating antigens. The Nter antiserum displayed higher titer than Cter antiserum, at 1/64,000 and 1/32,000 dilutions, respectively. The purification step further yielded 0.5 mg/mL of purified IgGs from 3 mL of antisera. The purified Nter IgG showed a significantly (p < 0.05) higher binding affinity towards peptide-BSA and goat αs1-casein, with lower Kd value at 5.063 × 10−3 μM compared to 9.046 × 10−3 μM for the Cter IgG. A cross-reactivity test showed that there was no binding in neither Nter nor Cter IgGs towards protein extracts from the milk of cow, buffalo, horse and camel. High-quality antibodies generated will allow further development of immuno-based analytical methods and future in vitro studies to be conducted on goat αs1-casein.

scholarly journals Cloning, expression and characterization of SeM protein of Streptococcus equi subsp. equi and evaluation of its use as antigen in an indirect ELISA

2014 ◽  
Vol 66 (4) ◽  
pp. 1015-1022 ◽  
Author(s):  
C.M. Moraes ◽  
F.R. Conceição ◽  
A.S.R. Rocha ◽  
A.G. Santos Júnior ◽  
L.M. Ribas ◽  
...  
Keyword(s):  
Immune Status ◽  
Indirect Elisa ◽  
High Specificity ◽  
Disease Diagnosis ◽  
Bacterial Isolation ◽  
Serum Samples ◽  
Gene Encoding ◽  
Specificity And Sensitivity ◽  
Streptococcus Equi

Strangles is an economically important horse disease caused by Streptococcus equi subsp. equi. The diagnosis can be confirmed either directly by bacterial isolation and PCR or by ELISA, which is an indirect method based on the detection of serum antibodies. The aim of this study was to clone, express and characterize the SeM protein of Streptococcus equi subsp. equi, evaluate its use as antigen in indirect ELISA and determine its performance to distinguish sera of negative, vaccinated and positive animals. This was initially performed by cloning the gene encoding the SeM protein and its expression in Escherichia coli. Subsequently, the protein produced was characterized and used as antigen in ELISA. Serum samples for evaluation were taken from 40 negative foals, 46 horses vaccinated with a commercial vaccine against strangles and 46 horses diagnosed with the disease. The test showed high specificity and sensitivity, allowing discrimination between negative and positive, positive and vaccinated animals, and vaccinated animals and negative sera. Thus, it was concluded that the protein produced rSeM, which can be used as antigen for disease diagnosis, and the described ELISA might be helpful to evaluate the immune status of the herd.

scholarly journals Electrochemical Biosensors as Potential Diagnostic Devices for Autoimmune Diseases

Biosensors ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 38 ◽  
Author(s):  
Anca Florea ◽  
Gheorghe Melinte ◽  
Ioan Simon ◽  
Cecilia Cristea
Keyword(s):  
Autoimmune Disease ◽  
Early Diagnosis ◽  
Point Of Care ◽  
Low Cost ◽  
Therapy Monitoring ◽  
Specific Interaction ◽  
Sample Pretreatment ◽  
Disease Diagnosis ◽  
Clinical Analysis ◽  
Electrochemical Biosensors

An important class of biosensors is immunosensors, affinity biosensors that are based on the specific interaction between antibodies and antigens. They are classified in four classes based on the type of employed transducer: electrochemical, optical, microgravimetric, and thermometric and depending on the type of recognition elements, antibodies, aptamers, microRNAs and recently peptides are integrating parts. Those analytical devices are able to detect peptides, antibodies and proteins in various sample matrices, without many steps of sample pretreatment. Their high sensitivity, low cost and the easy integration in point of care devices assuring portability are attracting features that justify the increasing interest in their development. The use of nanomaterials, simultaneous multianalyte detection and integration on platforms to form point-of-care devices are promising tools that can be used in clinical analysis for early diagnosis and therapy monitoring in several pathologies. Taking into account the growing incidence of autoimmune disease and the importance of early diagnosis, electrochemical biosensors could represent a viable alternative to currently used diagnosis methods. Some relevant examples of electrochemical assays for autoimmune disease diagnosis developed in the last several years based on antigens, antibodies and peptides as receptors were gathered and will be discussed further.

scholarly journals MicroRNAs as Potential Biomarkers in Cancer: Opportunities and Challenges

2015 ◽  
Vol 2015 ◽  
pp. 1-17 ◽  
Author(s):  
Huiyin Lan ◽  
Haiqi Lu ◽  
Xian Wang ◽  
Hongchuan Jin
Keyword(s):  
Expression Profiles ◽  
High Specificity ◽  
Detection Methods ◽  
Messenger Rnas ◽  
Aberrant Expression ◽  
Small Noncoding Rnas ◽  
Human Cancers ◽  
Specificity And Sensitivity ◽  
Broad Array ◽  
Potential Biomarkers

MicroRNAs (miRNAs) are a group of small noncoding RNAs (ncRNAs) that posttranscriptionally regulate gene expression by targeting their corresponding messenger RNAs (mRNAs). Dysregulated miRNAs have been considered as a new type of ‘‘oncomiRs’’ or ‘‘tumor suppressors,” playing essential roles in cancer initiation and progression. Using genome-wide detection methods, ubiquitously aberrant expression profiles of miRNAs have been identified in a broad array of human cancers, showing great potential as novel diagnostic and prognostic biomarkers of cancer with high specificity and sensitivity. The detectable miRNAs in tissue, blood, and other body fluids with high stability provide an abundant source for miRNA-based biomarkers in human cancers. Despite the fact that an increasing number of potential miRNA biomarkers have been reported, the transition of miRNAs-based biomarkers from bench to bedside still necessitates addressing several challenges. In this review, we will summarize our current understanding of miRNAs as potential biomarkers in human cancers.

scholarly journals Development of NCOVID-19 Colloidal Gold Immunochromatographic Test Strip

2021 ◽  
Vol 10 (1) ◽  
pp. 1
Author(s):  
Wenyi Liu ◽  
Zhaohua Li
Keyword(s):  
Colloidal Gold ◽  
Low Cost ◽  
Virus Detection ◽  
High Specificity ◽  
Accurate Method ◽  
Rapid Screening ◽  
Nucleic Acid Detection ◽  
Specificity And Sensitivity ◽  
Control Serum

<div><p>Purpose: To establish a fast, simple and accurate method and immunoassay test card for the detection of new coronavirus (nCOVID-19) antigen. Methods: In this study, colloidal gold immunochromatography technology was used to detect nCOVID-19 virus antigens through the sandwich method. At the same time, the preparation plan of colloidal gold was improved, and the application of rapid immune-diagnosis technology in other fields was developed. In this study, purified recombinant nCOVID-19 nucleocapsid protein is used as the antigen to prepare murine monoclonal antibodies. The BN02 antibody produced by the mouse is used as the detection antibody to couple with colloidal gold, forming a gold-labeled complex probe. BN9m1 is used as the coating antibody for the C-line, and ProA is used for the T-line. The polymerization of colloidal gold particles enables us to detect the new coronavirus antigen’s appearance. Thus an in vitro rapid detection kit for virus detection can be made. Results: The positive detection rate of the antigen quality control serum with this colloidal gold reagent was 100%. The specificity was 100%, and the sensitivity was 1ng/ml.  Conclusion: The nCOVID-19 antigen detection reagent (colloidal gold method) developed in this research has high specificity and sensitivity, and can be used in conjunction with nucleic acid detection. As a means of detecting nCOVID-19, it can achieve qualitative and rapid screening of samples with advantage such as accuracy, repeatability, and low cost.</p></div>

Shortest Unique Representative Hidden Markov Model (SurHMM) for Detecting Protein Toxins, Virulence Factors and Antibiotic Resistance Genes

2021 ◽  
Author(s):  
Gary Xie ◽  
Jeanne M Fair
Keyword(s):  
Markov Model ◽  
Hidden Markov Model ◽  
Hidden Markov ◽  
Sequence Similarity ◽  
Antibiotic Resistance Genes ◽  
High Specificity ◽  
False Positives ◽  
Bacterial Toxin ◽  
Specificity And Sensitivity ◽  
Next Generation Sequencing Ngs

Abstract Objective: Currently, next generation sequencing (NGS) is widely used to decode potential novel or variant pathogens both in emergent outbreaks and in routine clinical practice. However, the efficient identification of novel or diverged pathogenomic compositions remains a big challenge. It is especially true for short DNA sequence fragments from NGS, since sequence similarity searching is vulnerable to false negatives or false positives, as mismatching or matching with unrelated proteins. Therefore, this study aimed to establish a bioinformatics approach that can generate unique motif sequences for profiling searching, resulting in high specificity and sensitivity. Results: In this study, we introduced a shortest unique representative hidden Markov model (HMM) approach to identify bacterial toxin, virulence factor (VF), and antimicrobial resistance (AR) in short sequence reads. We first construct unique representative domain sequences of toxin genes, VFs, and ARs to avoid potential false positives, and then to use HMM models to accurately identify potential toxin, VF, and AR fragments. The benchmark shows this approach can achieve relatively high specificity and sensitivity if the appropriate cutoff value is applied.

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