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1.
Biosensors and Bioelectronics ; : 114340, 2022.
Article in English | ScienceDirect | ID: covidwho-1819434
2.
Emerg Microbes Infect ; 11(1): 629-638, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-1665837

ABSTRACT

Mounting evidence indicates that SARS-CoV-2 can infect multiple systemic tissues, but few studies have evaluated SARS-CoV-2 RNA dynamics in multiple specimen types due to their reduced accessibility and diminished performance of RT-qPCR with non-respiratory specimens. Here, we employed an ultrasensitive CRISPR-RT-PCR assay to analyze longitudinal mucosal (nasal, buccal, pharyngeal, and rectal), plasma, and breath samples from SARS-CoV-2-infected non-human primates (NHPs) to detect dynamic changes in SARS-CoV-2 RNA level and distribution among these specimens. We observed that CRISPR-RT-PCR results consistently detected SARS-CoV-2 RNA in all sample types at most time points post-infection, and that SARS-CoV-2 infection dose and administration route did not markedly affect the CRISPR-RT-PCR signal detected in most specimen types. However, consistent RT-qPCR positive results were restricted to nasal, pharyngeal, and rectal swab samples, and tended to decrease earlier than CRISPR-RT-PCR results, reflecting lower assay sensitivity. SARS-CoV-2 RNA was detectable in both pulmonary and extrapulmonary specimens from early to late infection by CRISPR-RT-PCR, albeit with different abundance and kinetics, with SARS-CoV-2 RNA increases detected in plasma and rectal samples trailing those detected in upper respiratory tract samples. CRISPR-RT-PCR assays for SARS-CoV-2 RNA in non-respiratory specimens may thus permit direct diagnosis of suspected COVID-19 cases missed by RT-PCR, while tracking SARS-CoV-2 RNA in minimally invasive alternate specimens may better evaluate the progression and resolution of SARS-CoV-2 infections.


Subject(s)
COVID-19 , SARS-CoV-2 , Animals , Humans , Primates , RNA, Viral/analysis , Sensitivity and Specificity , Serologic Tests
3.
Mikrochim Acta ; 188(10): 352, 2021 Sep 23.
Article in English | MEDLINE | ID: covidwho-1432545

ABSTRACT

Extracellular ATP as a purinergic signaling molecule, together with ATP receptor, are playing an important role in tumor growth, therapy resistance, and host immunity suppression. Meanwhile ATP is a crucial indicator for cellular energy status and viability, thus a vital variable for tissue regeneration and in vitro tissue engineering. Most recent studies on COVID-19 virus suggest infection caused ATP deficit and release as a major characterization at the early stage of the disease and major causes for disease complications. Thus, imaging ATP molecule in both cellular and extracellular contexts has many applications in biology, engineering, and clinics. A sensitive and selective fluorescence "signal-on" probe for ATP detection was constructed, based on the base recognition between a black hole quencher (BHQ)-labeled aptamer oligonucleotide and a fluorophore (Cy5)-labeled reporter flare. The probe was able to detect ATP in solution with single digit µM detection limit. With the assistance of lipofectamine, this probe efficiently entered and shined in the model cells U2OS within 3 h. Further application of the probe in specific scenery, cardio-tissue engineering, was also tested where the ATP aptamer complex was able to sense cellular ATP status in a semi-quantitative manner, representing a novel approach for selection of functional cardiomyocytes for tissue engineering. At last a slight change in probe configuration in which a flexible intermolecular A14 linker was introduced granted regeneration capability. These data support the application of this probe in multiple circumstances where ATP measurement or imaging is on demand.


Subject(s)
Adenosine Triphosphate/analysis , Aptamers, Nucleotide , Carbocyanines , Fluorescent Dyes , Animals , Animals, Newborn , Cell Line , Fluorescence , Humans , Myocytes, Cardiac , Rats
4.
Nat Nanotechnol ; 16(9): 1039-1044, 2021 09.
Article in English | MEDLINE | ID: covidwho-1322483

ABSTRACT

Plasma SARS-CoV-2 RNA may represent a viable diagnostic alternative to respiratory RNA levels, which rapidly decline after infection. Quantitative PCR with reverse transcription (RT-qPCR) reference assays exhibit poor performance with plasma, probably reflecting the dilution and degradation of viral RNA released into the circulation, but these issues could be addressed by analysing viral RNA packaged into extracellular vesicles. Here we describe an assay approach in which extracellular vesicles directly captured from plasma are fused with reagent-loaded liposomes to sensitively amplify and detect a SARS-CoV-2 gene target. This approach accurately identified patients with COVID-19, including challenging cases missed by RT-qPCR. SARS-CoV-2-positive extracellular vesicles were detected at day 1 post-infection, and plateaued from day 6 to the day 28 endpoint in a non-human primate model, while signal durations for 20-60 days were observed in young children. This nanotechnology approach uses a non-infectious sample and extends virus detection windows, offering a tool to support COVID-19 diagnosis in patients without SARS-CoV-2 RNA detectable in the respiratory tract.


Subject(s)
COVID-19/diagnosis , Extracellular Vesicles/metabolism , Liposomes/therapeutic use , RNA, Viral/blood , SARS-CoV-2/isolation & purification , Animals , Biosensing Techniques , COVID-19/blood , COVID-19 Nucleic Acid Testing , Chlorocebus aethiops , Disease Models, Animal , HEK293 Cells , Humans , Kinetics , Liposomes/metabolism , RNA, Viral/genetics , SARS-CoV-2/genetics , Tetraspanin 28/immunology , Tetraspanin 28/metabolism
5.
Biosens Bioelectron ; 179: 113074, 2021 May 01.
Article in English | MEDLINE | ID: covidwho-1064881

ABSTRACT

On global scale, the current situation of pandemic is symptomatic of increased incidences of contagious diseases caused by pathogens. The faster spread of these diseases, in a moderately short timeframe, is threatening the overall population wellbeing and conceivably the economy. The inadequacy of conventional diagnostic tools in terms of time consuming and complex laboratory-based diagnosis process is a major challenge to medical care. In present era, the development of point-of-care testing (POCT) is in demand for fast detection of infectious diseases along with "on-site" results that are helpful in timely and early action for better treatment. In addition, POCT devices also play a crucial role in preventing the transmission of infectious diseases by offering real-time testing and lab quality microbial diagnosis within minutes. Timely diagnosis and further treatment optimization facilitate the containment of outbreaks of infectious diseases. Presently, efforts are being made to support such POCT by the technological development in the field of internet of medical things (IoMT). The IoMT offers wireless-based operation and connectivity of POCT devices with health expert and medical centre. In this review, the recently developed POC diagnostics integrated or future possibilities of integration with IoMT are discussed with focus on emerging and re-emerging infectious diseases like malaria, dengue fever, influenza A (H1N1), human papilloma virus (HPV), Ebola virus disease (EVD), Zika virus (ZIKV), and coronavirus (COVID-19). The IoMT-assisted POCT systems are capable enough to fill the gap between bioinformatics generation, big rapid analytics, and clinical validation. An optimized IoMT-assisted POCT will be useful in understanding the diseases progression, treatment decision, and evaluation of efficacy of prescribed therapy.


Subject(s)
Biosensing Techniques/instrumentation , Communicable Diseases/diagnosis , Internet of Things , Point-of-Care Testing , Animals , Artificial Intelligence , Biosensing Techniques/methods , COVID-19/diagnosis , Coronavirus Infections/diagnosis , Dengue/diagnosis , Equipment Design , HIV Infections/diagnosis , Hemorrhagic Fever, Ebola/diagnosis , Humans , Influenza, Human/diagnosis , Malaria/diagnosis , Orthomyxoviridae Infections/diagnosis , Zika Virus Infection/diagnosis
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