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1.
PLoS One ; 19(7): e0306966, 2024.
Article in English | MEDLINE | ID: mdl-38990907

ABSTRACT

The most common risk factor of computer workers is poor head and neck posture. Therefore, upright seated posture has been recommended repeatedly. However, maintaining an upright seated posture is challenging during computer work and induces various complaints, such as fatigue and discomfort, which can interfere working performance. Therefore, it is necessary to maintain an upright posture without complaints or intentional efforts during long-term computer work. Alignment devices are an appropriate maneuver to support postural control for maintaining head-neck orientation and reduce head weight. This study aimed to demonstrate the effects of workstations combined with alignment device on head-neck alignment, muscle properties, comfort and working memory ability in computer workers. Computer workers (n = 37) participated in a total of three sessions (upright computer (CPT_U), upright support computer (CPT_US), traction computer (CPT_T) workstations). The craniovertebral angle, muscles tone and stiffness, visual analog discomfort scale score, 2-back working memory performance, and electroencephalogram signals were measured. All three workstations had a substantial effect on maintaining head-neck alignment (p< 0.001), but only CPT_US showed significant improvement on psychological comfort (p = 0.04) and working memory performance (p = 0.024), which is consistent with an increase in delta power. CPT_U showed the increased beta 2 activity, discomfort, and false rates compared to CPT_US. CPT_T showed increased alpha and beta 2 activity and decreased delta activity, which are not conductive to working memory performance. In conclusion, CPT_US can effectively induce efficient neural oscillations without causing any discomfort by increasing delta and decreasing beta 2 activity for working memory tasks.


Subject(s)
Head , Memory, Short-Term , Posture , Humans , Memory, Short-Term/physiology , Male , Adult , Posture/physiology , Head/physiology , Computers , Female , Neck/physiology , Electroencephalography , Young Adult
2.
Healthcare (Basel) ; 12(12)2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38921277

ABSTRACT

Forward head posture (FHP) is a common postural problem experienced by most people. However, its effect on brain activity is still unknown. Accordingly, we aimed to observe changes in brain waves at rest to determine the effect of FHP on the nervous systems. A total of 33 computer users (Male = 17; Female = 16; age = 22.18 ± 1.88) were examined in both FHP and neutral posture. For each session, brain waves were measured for 5 min, and then muscle mechanical properties and cranio-vertebral angle (CVA) were measured. Changes in brain waves between the neutral posture and FHP were prominent in gamma waves. A notable increase was confirmed in the frontal and parietal lobes. That is, eight channels in the frontal lobe and all channels in the parietal lobe showed a significant increase in FHP compared to neutral posture. Additionally, FHP changes were associated with a decrease in CVA (p < 0.001), an increase in levator scapulae tone (Right, p = 0.014; Left, p = 0.001), and an increase in right sternocleidomastoid stiffness (p = 0.002), and a decrease in platysma elasticity (Right, p = 0.039; Left, p = 0.017). The change in CVA was found to have a negative correlation with the gamma activity (P7, p = 0.044; P8, p = 0.004). Therefore, increased gamma wave activity in FHP appears to be related to CVA decrease due to external force that was applied to the nervous system and cervical spine.

3.
Biosens Bioelectron ; 259: 116375, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38749283

ABSTRACT

Since the outbreak of the novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) at the end of 2019, the spread of the virus has posed a significant threat to public health and the global economy. This work proposed a one-step, dual-structure-switching aptamer-mediated signal amplification cascade for rapid and sensitive detection of the SARS-CoV-2 nucleocapsid protein. This system consisted of two DNA aptamers with structure-switching functionality and fuel DNA, where a cascade of strand hybridization and displacement triggered fluorescence generation and signal amplification. This aptamer-based amplification cascade required neither an amplification stage using enzymes nor pre-processing steps such as washing, viral isolation, and gene extraction. The assay could distinguish SARS-CoV-2 from other respiratory viruses and detect up to 1.0 PFU/assay of SARS-CoV-2 within 30 min at room temperature. In 35 nasopharyngeal clinical samples, the assay accurately assessed 25 positive and 10 negative clinical swab samples, which were confirmed using quantitative polymerase chain reaction. The strategy reported herein can help detect newly emerging pathogens and biomarkers of various diseases in liquid samples. In addition, the developed detection system consisting of only DNA and fluorophores can be widely integrated into liquid biopsy platforms for disease diagnosis.


Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , COVID-19 , Nucleic Acid Amplification Techniques , SARS-CoV-2 , SARS-CoV-2/isolation & purification , SARS-CoV-2/genetics , Humans , Biosensing Techniques/methods , Aptamers, Nucleotide/chemistry , COVID-19/virology , COVID-19/diagnosis , Nucleic Acid Amplification Techniques/methods , Coronavirus Nucleocapsid Proteins/genetics , Phosphoproteins/chemistry , Limit of Detection , COVID-19 Nucleic Acid Testing/methods , COVID-19 Nucleic Acid Testing/instrumentation
4.
Small ; : e2308317, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38564785

ABSTRACT

Proactive management of foodborne illness requires routine surveillance of foodborne pathogens, which requires developing simple, rapid, and sensitive detection methods. Here, a strategy is presented that enables the detection of multiple foodborne bacteria using a 3D nanostructure swab and deep learning-based Raman signal classification. The nanostructure swab efficiently captures foodborne pathogens, and the portable Raman instrument directly collects the Raman signals of captured bacteria. a deep learning algorithm has been demonstrated, 1D convolutional neural network with binary labeling, achieves superior performance in classifying individual bacterial species. This methodology has been extended to mixed bacterial populations, maintaining accuracy close to 100%. In addition, the gradient-weighted class activation mapping method is used to provide an investigation of the Raman bands for foodborne pathogens. For practical application, blind tests are conducted on contaminated kitchen utensils and foods. The proposed technique is validated by the successful detection of bacterial species from the contaminated surfaces. The use of a 3D nanostructure swab, portable Raman device, and deep learning-based classification provides a powerful tool for rapid identification (≈5 min) of foodborne bacterial species. The detection strategy shows significant potential for reliable food safety monitoring, making a meaningful contribution to public health and the food industry.

5.
Talanta ; 275: 126073, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38688085

ABSTRACT

Methicillin-resistant Staphylococcus aureus (MRSA) has a high incidence in infectious hospitals and communities, highlighting the need for early on-site detection due to its resistance to methicillin antibiotics. The present study introduces a highly sensitive detection system for mecA, a crucial methicillin marker, utilizing an RCA-based isothermal exponential amplification reaction. The G-quadruplex-based isothermal exponential amplification reaction (GQ-EXPAR) method designs probes to establish G-quadruplex secondary structures incorporating thioflavin T for fluorescence. The system, unlike conventional genetic detection methods, works with portable isothermal PCR devices (isoQuark), facilitating on-site detection. A detection limit of 0.1 fmol was demonstrated using synthetic DNA, and effective detection was proven using thermal lysis. The study also validated the detection of targets swabbed from surfaces within bacterial 3D nanostructures using the GQ-EXPAR method. After applying complementary sequences to the padlock probe for the target, the GQ-EXPAR method can be used on various targets. The developed method could facilitate rapid and accurate diagnostics within MRSA strains.


Subject(s)
G-Quadruplexes , Methicillin-Resistant Staphylococcus aureus , Nucleic Acid Amplification Techniques , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Methicillin-Resistant Staphylococcus aureus/genetics , Nucleic Acid Amplification Techniques/methods , Limit of Detection , Penicillin-Binding Proteins , Bacterial Proteins/genetics , DNA, Bacterial/genetics , DNA, Bacterial/analysis , Benzothiazoles/chemistry , Humans
6.
Food Chem ; 438: 138043, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-37992606

ABSTRACT

Listeria monocytogenes, a severe foodborne pathogen causing severe diseases underscores the necessity for the development of a detection system with high specificity, sensitivity and utility. Herein, the PoreGlow system, based on split green fluorescent protein (GFP), was developed and assessed for the fast and accurate detection of L. monocytogenes. Split GFP-encapsulated liposomes were optimized for targeted analysis. The system utilizes listeriolysin O (LLO), a toxin produced by L. monocytogenes that enlarges the pores split GFP-encapsulated liposomes, to detect L. monocytogenes by measuring the fluorescent signal generated when the encapsulated GFP is released and reacted with the externally added fragment of the split GFP. The system exhibited a limit of detection of 0.17 µg/ml for LLO toxin and 10 CFU/mL for L. monocytogenes with high sensitivity and specificity and no cross-reactivity with other bacteria. The PoreGlow system is practical, rapid, and does not require sample pre-treatment, making it a promising tool for the early detection of L. monocytogenes in food products, which is crucial for preventing outbreaks and protecting public health.


Subject(s)
Listeria monocytogenes , Listeriosis , Humans , Listeria monocytogenes/genetics , Listeriosis/metabolism , Listeriosis/microbiology , Green Fluorescent Proteins/genetics , Liposomes/metabolism , Hemolysin Proteins/genetics
7.
Nat Commun ; 14(1): 8033, 2023 Dec 05.
Article in English | MEDLINE | ID: mdl-38052830

ABSTRACT

Endonucleases have recently widely used in molecular diagnostics. Here, we report a strategy to exploit the properties of Argonaute (Ago) proteins for molecular diagnostics by introducing an artificial nucleic acid circuit with Ago protein (ANCA) method. The ANCA is designed to perform a continuous autocatalytic reaction through cross-catalytic cleavage of the Ago protein, enabling one-step, amplification-free, and isothermal DNA detection. Using the ANCA method, carbapenemase-producing Klebsiella pneumoniae (CPKP) are successfully detected without DNA extraction and amplification steps. In addition, we demonstrate the detection of carbapenem-resistant bacteria in human urine and blood samples using the method. We also demonstrate the direct identification of CPKP swabbed from surfaces using the ANCA method in conjunction with a three-dimensional nanopillar structure. Finally, the ANCA method is applied to detect CPKP in rectal swab specimens from infected patients, achieving sensitivity and specificity of 100% and 100%, respectively. The developed method can contribute to simple, rapid and accurate diagnosis of CPKP, which can help prevent nosocomial infections.


Subject(s)
Anti-Bacterial Agents , Nucleic Acids , Humans , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , beta-Lactamases/genetics , Argonaute Proteins/genetics , Argonaute Proteins/metabolism , Antibodies, Antineutrophil Cytoplasmic/metabolism , Nucleic Acids/metabolism , Bacteria/genetics , DNA/metabolism , Klebsiella pneumoniae/genetics , Klebsiella pneumoniae/metabolism , Microbial Sensitivity Tests
8.
J Hazard Mater ; 460: 132398, 2023 10 15.
Article in English | MEDLINE | ID: mdl-37639787

ABSTRACT

Over the past few years, infections caused by airborne pathogens have spread worldwide, infecting several people and becoming an increasingly severe threat to public health. Therefore, there is an urgent need for developing airborne pathogen monitoring technology for use in confined environments to enable epidemic prevention. In this study, we designed a colorimetry-based bacterial detection platform that uses a clustered regularly interspaced short palindromic repeat-associated protein 12a system to amplify signals and a urease enzyme to induce color changes. Furthermore, we have developed a smartphone application that can distinguish colors under different illumination conditions based on the HSV model and detect three types of disease-causing bacteria. Even synthetic oligomers of a few picomoles of concentration and genomic DNA of airborne bacteria smaller than several nanograms can be detected with the naked eye and using color analysis systems. Furthermore, in the air capture model system, the bacterial sample generated approximately a 2-fold signal difference compared with that in the control group. This colorimetric detection method can be widely applied for public safety because it is easy to use and does not require complex equipment.


Subject(s)
Colorimetry , Smartphone , Humans , Bacteria/genetics , Models, Biological , Public Health
9.
Adv Sci (Weinh) ; 10(14): e2205161, 2023 05.
Article in English | MEDLINE | ID: mdl-36950748

ABSTRACT

Although activin receptor IIB (ACVR2B) is emerging as a novel pathogenic receptor, its ligand and assembled components (or assembly) are totally unknown in the context of osteoarthritis (OA) pathogenesis. The present results suggest that upregulation of ACVR2B and its assembly could affect osteoarthritic cartilage destruction. It is shown that the ACVR2B ligand, activin A, regulates catabolic factor expression through ACVR2B in OA development. Activin A Tg mice (Col2a1-Inhba) exhibit enhanced cartilage destruction, whereas heterozygous activin A KO mice (Inhba+/- ) show protection from cartilage destruction. In silico analysis suggests that the Activin A-ACVR2B axis is involved in Nox4-dependent ROS production. Activin A Tg:Nox4 KO (Col2a1-Inhba:Nox4-/- ) mice show inhibition of experimental OA pathogenesis. NOX4 directly binds to the C-terminal binding site on ACVR2B-ACVR1B and amplifies the pathogenic signal for cartilage destruction through SMAD2/3 signaling. Together, the findings reveal that the ACVR2B assembly, which comprises Activin A, ACVR2B, ACVR1B, Nox4, and AP-1-induced HIF-2α, accelerates OA development. Furthermore, it is shown that shRNA-mediated ACVR2B knockdown or trapping ligands of ACVR2B abrogate OA development by competitively disrupting the ACVR2B-Activin A interaction. These results suggest that the ACVR2B assembly is required to amplify osteoarthritic cartilage destruction and could be a potential therapeutic target in efforts to treat OA.


Subject(s)
Chondrocytes , Osteoarthritis , Animals , Mice , Activin Receptors/metabolism , Chondrocytes/metabolism , Chondrocytes/pathology , Ligands , NADPH Oxidase 4/metabolism , Osteoarthritis/metabolism
10.
ACS Appl Mater Interfaces ; 15(6): 7759-7766, 2023 Feb 15.
Article in English | MEDLINE | ID: mdl-36748606

ABSTRACT

Infectious agents such as viruses pose significant threats to human health, being transmitted via direct contact as well as airborne transmission without direct contact, thus requiring rapid detection to prevent the spread of infectious diseases. In this study, we developed a conductive thread-based immunosensor (CT-IS), a biosensor to easily detect the presence of airborne viruses. CT-IS utilizes an antibody that specifically recognizes the HA protein of the pandemic influenza A (pH1N1) virus, which is incorporated into the conductive thread. The antigen-antibody interaction results in increased strain on the conductive thread in the presence of the pH1N1 virus, resulting in increased electrical resistance of the CT-IS. We evaluated the performance of this sensor using the HA protein and the pH1N1 virus, in addition to samples from patients infected with the pH1N1 virus. We observed a significant change in resistance in the pH1N1-infected patient samples (positive: n = 11, negative: n = 9), whereas negligible change was observed in the control samples (patients not infected with the pH1N1 virus; negative). Hence, the CT-IS is a lightweight fiber-type sensor that can be used as a wearable biosensor by combining it with textiles, to detect the pH1N1 virus in a person's vicinity.


Subject(s)
Biosensing Techniques , Influenza A Virus, H1N1 Subtype , Influenza, Human , Humans , Influenza, Human/diagnosis , Immunoassay , Antibodies
11.
Biosens Bioelectron ; 225: 115085, 2023 Apr 01.
Article in English | MEDLINE | ID: mdl-36696850

ABSTRACT

Accurate and efficient detection of DNA is crucial for disease diagnosis and health monitoring. The traditional methods for DNA analysis involve multiple steps, including sample preparation, lysis, extraction, amplification, and detection. In this study, we present a one-step elution-free DNA analysis method based on the combination of clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9)-mediated light-up aptamer transcription (CLAT) assay and a DNA-capturing poly(2-dimethylaminomethyl styrene) (pDMAMS)-coated tube. The sample solution and lysis buffer are added to the pDMAMS-coated tube, and the DNA is efficiently captured on the surface via electrostatic interaction and directly detected by CLAT assay. The ability of the CRISPR/Cas9 system to specifically recognize DNA enables direct detection of DNA captured on the pDMAMS-coated tube. The combination of CLAT assay and pDMAMS-coated tube simplifies DNA detection in a single tube without the need for complicated extraction steps, improving sensitivity. Our platform demonstrated attomolar sensitivity in the detection of target DNA in cell lysate (0.92 aM), urine (7.7 aM), and plasma (94.6 aM) samples within 1 h. The practical applicability of this method was further demonstrated in experiments with tumor-bearing mice. We believe that this approach brings us closer to an all-in-one DNA purification and detection tube system and has potential applications in tissue and liquid biopsies, as well as various other DNA sensing applications.


Subject(s)
Biosensing Techniques , CRISPR-Cas Systems , Mice , Animals , CRISPR-Cas Systems/genetics , DNA/analysis , Oligonucleotides
12.
Biosens Bioelectron ; 219: 114819, 2023 Jan 01.
Article in English | MEDLINE | ID: mdl-36327561

ABSTRACT

Clustered regularly interspaced short palindromic repeats (CRISPR)-based diagnostics have emerged as next-generation molecular diagnostics. In CRISPR-based diagnostics, Cas12 and Cas13 proteins have been widely employed to detect DNA and RNA, respectively. Herein, we developed a novel hybrid Cas protein capable of detecting universal nucleic acids (DNA and RNA). The CRISPR/hybrid Cas system simultaneously recognizes both DNA and RNA, enabling the dual detection of pathogenic viruses in a single tube. Using wild-type (WT) and N501Y mutant severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as detection models, we successfully detected both virus strains with a detection limit of 10 viral copies per reaction without cross-reactivity. Furthermore, it is demonstrated the detection of WT SARS-CoV-2 and N501Y mutant variants in clinical samples by using the CRISPR/hybrid Cas system. The hybrid Cas protein is expected to be utilized in a molecular diagnostic method for infectious diseases, tissue and liquid biopsies, and other nucleic acid biomarkers.

13.
Food Chem ; 403: 134317, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36182855

ABSTRACT

Ingesting large quantities of biogenic amines (BAs), which are released from spoiled foods, can have adverse side effects on the human body. Herein, we developed a colorimetric sensor using polydiacetylene (PDA)-based hydrogel beads that change color upon binding with BAs, thereby conveniently checking whether food is spoiled due to improper storage and distribution. The colorimetric sensor is fabricated by mixing PDA liposomes with an alginate solution. PDA undergoes a color change from blue to red when exposed to various external stimuli. In addition, alginate bestows the hydrogel with a three-dimensional porous structure, affording a large surface area. The PDA-based hydrogel beads can visually confirm the presence of BAs in solution or vapor form. Cadaverine and propylamine were rapidly detected with distinct color changes in the solution and vapor phases, respectively. The spoilage of pork meat at room temperature could be detected after two days as a 40.84% red chromatic shift.


Subject(s)
Colorimetry , Hydrogels , Humans , Colorimetry/methods , Biogenic Amines , Meat/analysis , Alginates
14.
Article in English | MEDLINE | ID: mdl-36361134

ABSTRACT

The forward head posture of visual display terminal (VDT) users induces various physical and cognitive clinical symptoms. However, few studies have been conducted to identify and solve problems associated with VDT posture. This study aimed to examine the adverse effects of VDT posture and the positive effects of traction-combined workstations by measuring postural alignment, muscle properties, blood velocity, preference, and working memory. Thirty-four healthy VDT users (18 males and 16 females aged 20-30 years) participated in the experiment at three workstations, including conventional (VDT_C), head support (VDT_S), and upright (VDT_U) workstations. They conducted 2-back working memory task. The craniovertebral angle (CVA), muscle tone and stiffness, blood velocity and visual analogue discomfort scale (VADS) were measured to examine the influence of workstations. VDT_C showed increased muscle tone or stiffness in the levator scapulae (LS), suboccipital muscle (SM), and sternocleidomastoid muscle (SCM) and an increased reaction time (RT) in working memory. However, VDT_S showed decreased stiffness and tone of SM and improved comfort. In addition, VDT_U showed decreased stiffness or tone of the LS and SCM and improved blood velocity and RT. In conclusion, maintaining neutral alignment significantly improved working memory performance, muscle properties, and blood velocity.


Subject(s)
Computer Terminals , Superficial Back Muscles , Male , Female , Humans , Memory, Short-Term , Traction , Hemodynamics , Cognition , Weight Loss
15.
Front Psychiatry ; 13: 925823, 2022.
Article in English | MEDLINE | ID: mdl-36147982

ABSTRACT

Background: In animal experiments, the habenula and septal nuclei are known as the key brain areas of depression. However, there are few magnetic resonance imaging (MRI) studies on the functional connectivity between these areas and the subcortical areas in humans with major depression. We aimed to investigate the difference in resting-state functional connectivity (RSFC) among the major regions of interest (ROI) in the subcortical areas, including both the habenula and septal nuclei. Methods: We performed the seed-to-voxel analysis to investigate the RSFC between both the habenula and septal nucleus, as well as other subcortical regions. Furthermore, ROI-to-ROI analysis was performed among the combinations of ROI pairs in the subcortical areas. Results: The seed-to-voxel analysis showed a lower RSFC between the left habenula and the cerebellum in major depressive disorder (MDD) than in healthy controls (HCs). As a result of ROI-to-ROI analysis in subcortical areas, a total of 31 pairs of FCs in the MDD group showed a lower RSFC than in the HCs group. Conclusion: This study revealed a lower RSFC between the left habenula and cerebellum in patients with MDD and reduced RSFC among numerous subcortical areas. These new findings on the neural circuitry of MDD might contribute to an in-depth understanding of depression.

16.
Sensors (Basel) ; 22(16)2022 Aug 18.
Article in English | MEDLINE | ID: mdl-36015953

ABSTRACT

The diagnosis of small vessel disease is attracting interest; however, it remains difficult to visualize the microvasculature using 3 Tesla (T) magnetic resonance imaging (MRI). Therefore, this study aimed to visualize the microvascular structure and measure a slow flow on 3T MRI. We developed a microcirculation system using piezoelectric pumps connected to small tubes (0.4, 0.5, 0.8, and 1.0 mm) and evaluated various MR sequences and imaging parameters to identify the most appropriate acquisition parameters. We found that the system could image small structures with a diameter of 0.5 mm or more when using a 1 m-long tube (maximal signal intensity of 241 in 1 mm, 199 in 0.8 mm, and 133 in 0.5 mm). We also found that the highest signal-to-noise ratio (SNR) appeared on 2-dimensional time-of-flight low-resolution imaging and that the flow velocity (10.03 cm/s) was similar to the actual velocity (11.01 cm/s in a flowmeter) when velocity encoding of 30 cm/s was used in a 0.8 mm-diameter tube. In conclusion, this study demonstrates that a microcirculation system can be used to image small vessels. Therefore, our results could serve as a basis for research on vessels' anatomical structure and pathophysiological function in small vessel disease.


Subject(s)
Magnetic Resonance Imaging , Ultrasonics , Magnetic Resonance Imaging/methods , Microcirculation , Microvessels/diagnostic imaging , Phantoms, Imaging , Signal-To-Noise Ratio
17.
ACS Nano ; 16(7): 11300-11314, 2022 07 26.
Article in English | MEDLINE | ID: mdl-35735410

ABSTRACT

Coronavirus disease (COVID-19) has affected people for over two years. Moreover, the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants has raised concerns regarding its accurate diagnosis. Here, we report a colorimetric DNAzyme reaction triggered by loop-mediated isothermal amplification (LAMP) with clustered regularly interspaced short palindromic repeats (CRISPR), referred to as DAMPR assay for detecting SARS-CoV-2 and variants genes with attomolar sensitivity within an hour. The CRISPR-associated protein 9 (Cas9) system eliminated false-positive signals of LAMP products, improving the accuracy of DAMPR assay. Further, we fabricated a portable DAMPR assay system using a three-dimensional printing technique and developed a machine learning (ML)-based smartphone application to routinely check diagnostic results of SARS-CoV-2 and variants. Among blind tests of 136 clinical samples, the proposed system successfully diagnosed COVID-19 patients with a clinical sensitivity and specificity of 100% each. More importantly, the D614G (variant-common), T478K (delta-specific), and A67V (omicron-specific) mutations of the SARS-CoV-2 S gene were detected selectively, enabling the diagnosis of 70 SARS-CoV-2 delta or omicron variant patients. The DAMPR assay system is expected to be employed for on-site, rapid, accurate detection of SARS-CoV-2 and its variants gene and employed in the diagnosis of various infectious diseases.


Subject(s)
COVID-19 , DNA, Catalytic , Humans , SARS-CoV-2/genetics , DNA, Catalytic/genetics , COVID-19/diagnosis , Smartphone , Colorimetry , Nucleic Acid Amplification Techniques/methods , Molecular Diagnostic Techniques/methods , Sensitivity and Specificity
18.
Talanta ; 246: 123502, 2022 Aug 15.
Article in English | MEDLINE | ID: mdl-35523021

ABSTRACT

MicroRNAs (miRNAs) are important diagnostic and prognostic biomarkers for various tumors. Currently, many diagnostic systems have been developed to detect miRNAs, but simple techniques for detecting miRNAs are still required. Recently, we reported that the expression of miRNA-135b is upregulated in gastric epithelial cells during gastric inflammation and carcinogenesis. Our aim was to develop an in vitro diagnostic platform to analyze the expression of gastric cancer-related biomarkers in the blood. The diagnostic platform comprised an isothermal amplification-based lateral flow biosensor (IA-LFB) that enables easy diagnosis of gastric cancer through visual observation. In this platform, trace amounts of biomarkers are isothermally amplified through rolling circle amplification (RCA), and the amplified product is grafted to the LFB. The performance of the IA-LFB was confirmed using RNAs extracted from in vitro and in vivo models. The platform could detect target miRNAs within 3 h with excellent sensitivity and selectivity. In particular, the IA-LFB could detect the overexpression of gastric cancer-related markers (miRNA-135b and miRNA-21) in RNAs extracted from the blood of patients with various stages (stages 1-4) of gastric cancer compared to that in healthy volunteers. Therefore, IA-LFB is a simple and sensitive in vitro diagnostic system for detecting gastric cancer-related biomarkers and can contribute to the early diagnosis and prognosis monitoring of gastric cancer. Furthermore, this technology can be applied to systems that can detect multiple biomarkers related to various diseases (such as infectious and genetic diseases).


Subject(s)
Biosensing Techniques , MicroRNAs , Stomach Neoplasms , Biosensing Techniques/methods , Humans , MicroRNAs/genetics , Nucleic Acid Amplification Techniques/methods , Stomach Neoplasms/diagnosis , Stomach Neoplasms/genetics
19.
Biosens Bioelectron ; 209: 114279, 2022 Aug 01.
Article in English | MEDLINE | ID: mdl-35447599

ABSTRACT

Alzheimer's disease (AD), one of the leading senile disorders in the world, causes severe memory loss and cognitive impairment. To date, there is no clear cure for AD. However, early diagnosis and monitoring can help mitigate the effects of this disease. In this study, we reported a platform for diagnosing early-stage AD using microRNAs (miRNAs) in the blood as biomarkers. First, we selected an appropriate target miRNA (miR-574-5p) using AD model mice (4-month-old 5XFAD mice) and developed a hydrogel-based sensor that enabled high-sensitivity detection of the target miRNA. This hydrogel contained catalytic hairpin assembly (CHA) reaction-based probes, leading to fluorescence signal amplification without enzymes and temperature changes, at room temperature. This sensor exhibited high sensitivity and selectivity, as evidenced by its picomolar-level detection limit (limit of detection: 1.29 pM). Additionally, this sensor was evaluated using the plasma of AD patients and non-AD control to validate its clinical applicability. Finally, to use this sensor as a point-of-care-testing (POCT) diagnostic system, a portable fluorometer was developed and verified for feasibility of application.


Subject(s)
Alzheimer Disease , Biosensing Techniques , MicroRNAs , Animals , Early Diagnosis , Humans , Hydrogels , Mice , MicroRNAs/genetics
20.
Biosens Bioelectron ; 209: 114256, 2022 Aug 01.
Article in English | MEDLINE | ID: mdl-35430408

ABSTRACT

In this study, we uncover a ligation-free DNA extension method in two adjacent fragmented probes, which are hybridized to target RNA, for developing a ligation-free nucleic acid amplification reaction. In this reaction, DNA elongation occurs from a forward probe to a phosphorothioated-hairpin probe in the presence of target RNA regardless of ligation. The second DNA elongation then occurs simultaneously at the nick site of the phosphorothioated probe and the self-priming region. Therefore, the binding site of the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas) 12a is repeatedly amplified, inducing a fluorescence signal in the presence of CRISPR-Cas12a. This ligation-free isothermal gene amplification method enables the detection of target RNA with 49.2 fM sensitivity. Moreover, two types of mRNA detection are feasible, thus, demonstrating the potential of this method for cancer companion diagnostics. Notably, the proposed method also demonstrates efficacy when applied for the detection of mRNA extracted from human cells and tumor-bearing mouse tissue and urine samples. Hence, this newly developed ligation-free isothermal nucleic acid amplification system is expected to be widely used in a variety of gene detection platforms.


Subject(s)
Biosensing Techniques , CRISPR-Cas Systems , Animals , Biosensing Techniques/methods , CRISPR-Cas Systems/genetics , DNA/genetics , Mice , Nucleic Acid Amplification Techniques/methods , RNA , RNA, Messenger
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