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Wastewater surveillance has been widely used to track the prevalence of SARS-CoV-2 in communities. Although some studies have investigated the decay of SARS-CoV-2 RNA in wastewater, understanding about its fate during wastewater transport in real sewers is still limited. This study aims to assess the impact of sewer biofilms on the dynamics of SARS-CoV-2 RNA concentration in naturally contaminated real wastewater (raw influent wastewater without extra SARS-CoV-2 virus/gene seeding) using a simulated laboratory-scale sewer system. The results indicated that, with the sewer biofilms, a 90% concentration reduction of the SARS-CoV-2 RNA was observed within 2 h both in wastewater of gravity (GS, gravity-driven sewers) and rising main (RM, pressurized sewers) sewer reactors. In contrast, the 90% reduction time was 8–26 h in control reactors without biofilms. The concentration reduction of SARS-CoV-2 RNA in wastewater was significantly more in the presence of sewer biofilms. In addition, an accumulation of c.a. 260 and 110 genome copies/cm2 of the SARS-CoV-2 E gene was observed in the sewer biofilm samples from RM and GS reactors within 12 h, respectively. These results confirmed that the in-sewer concentration reduction of SARS-CoV-2 RNA in wastewater was likely caused by the partition to sewer biofilms. The need to investigate the in-sewer dynamic of SARS-CoV-2 RNA, such as the variation of RNA concentration in influent wastewater caused by biofilm attachment and detachment, was highlighted by the significantly enhanced reduction rate of SARS-CoV-2 RNA in wastewater of sewer biofilm reactors and the accumulation of SARS-CoV-2 RNA in sewer biofilms. Further research should be conducted to investigate the in-sewer transportation of SARS-CoV-2 and their RNA and evaluate the role of sewer biofilms in leading to underestimates of COVID-19 prevalence in communities.
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Introduction/Objective COVID-19 pandemic severely impacted the healthcare and economy on a global scale. It is widely recognized that mass testing is an efficient way to contain the spread of SARS-CoV-2 infection as well as aid in the development of informed policies for disease management. Here we optimized two different protocols for qRT- PCR with direct samples and systematically compared them with the laboratory standard qRT-PCR detection assay. Methods/Case Report RNA samples from 270 subjects collected in two phases at 2020-2021. The groups consisted from positive (n = 240) and negative (n = 30) samples. We compared the performance of qRT-PCR in direct heat- inactivated (95 °C for 5 min, H), heat-inactivated and pelleted (95 °C for 5 min and centrifuged for 10 min at 12,000 g, HC) against standard laboratory protocol for SARS-CoV-2 qRT-PCR (targeting ORF1ab and N genes). Accuracy, sensitivity, and specificity for PCR assays were calculated using caret and epiR packages available in the R software environment for statistical computing. The Wilcoxon matched rank test was used to compare differences in Ct values. Results (if a Case Study enter NA) Our study suggests that HC samples show higher accuracy for SARS-CoV-2 detection PCR assay compared to direct H (89 % (95 % CI: 80–95 %) vs 83 % (95 % CI: 74–91 %) of the detection in RNA). The median ΔCt was lower by 1.55 and 2.29 cycles (Wilcoxon signed-rank test p = 0.0018 and < 0.0001 for ORF1ab and N genes, accordingly) in HC samples compared to H samples. Conclusion Our results suggest that purified RNA provides more accurate results;heat-inactivated and pelleted sample testing with qRT-PCR showed a slight drop in accuracy. However, the latter could also help to significantly increase testing capacity. Switching to the direct sample testing is justified if the number of tests is doubled at least.
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Introduction/Objective The public health emergency of the COVID-19 pandemic emphasized the crucial role of medical laboratory professionals and scientists in molecular diagnostics laboratories to ensure success in infection control strategies. The demand for laboratory testing using nucleic acid amplification tests to detect SARS-CoV-2 RNA imposed strains in laboratory supplies. Here, we explored an alternative cost-effective solution that will simplify the pre-PCR steps by using a simple heating method to release viral RNA. Methods/Case Report Samples tested using the reference automated extraction method were used:100 samples identified as positive for SARS-CoV-2 RNA and 500 samples tested negative for SARS-CoV-2 RNA were used for the study and sorted with equal distribution according to Ct values of (a) <20, (b) 20–30, and (c) >30.100 ul from swab preserved in Universal Transport Medium was treated with 30 μg of proteinase K, and another set was tested without proteinase K pre-treatment. All samples with or without proteinase K were diluted to minimize PCR inhibitors. The thermal shock protocol was set at (98°C, 5 minutes;4°C, 2 minutes) and screened for purity. Performance and method verification studies were performed. Internal extraction, positive template, and no template controls were markers used for testing quality. The experimental study was performed by qualified testing personnel and all under the same experimental conditions. Results (if a Case Study enter NA) The Ct values from the thermal shock RNA release were compared to the automated extraction method and statistically analyzed.The criteria for acceptability for validation of this new RNA extraction proceeding were set to 100% concordance compared to the commercial kit using an automated extraction. PCR efficiency was at 98% and a slope of -3.3. Within run precision of 2% and limits of detection from 200 to 20,000 copies/uL The method 100% (50/50) concordance on samples previously identified as negative by automated methods and identified 86% (86/100) with a mean difference of 3 Ct. Conclusion Our findings suggest that the thermal shock treatment of nasopharyngeal swabs in viral transport media can successfully extract viral nucleic acid for nucleic acid amplification and is a reasonable alternative for chemical extraction methods when molecular diagnostic laboratories persistently encounter supply chain issues.
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COVID-19 brought about the mRNA vaccine and a paradigm shift to a new mode of treating and preventing diseases. Synthetic RNA products are a low-cost solution based on a novel method of using nucleosides to act as an innate medicine factory with unlimited therapeutic possibilities. In addition to the common perception of vaccines preventing infections, the newer applications of RNA therapies include preventing autoimmune disorders, such as diabetes, Parkinson's disease, Alzheimer's disease, and Down syndrome; now, we can deliver monoclonal antibodies, hormones, cytokines, and other complex proteins, reducing the manufacturing hurdles associated with these products. Newer PCR technology removes the need for the bacterial expression of DNA, making mRNA a truly synthetic product. AI-driven product design expands the applications of mRNA technology to repurpose therapeutic proteins and test their safety and efficacy quickly. As the industry focuses on mRNA, many novel opportunities will arise, as hundreds of products under development will bring new perspectives based on this significant paradigm shift-finding newer solutions to existing challenges in healthcare.
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Background: As the COVID era unfolds, researchers reveal that rapid changes in viral genetic material allow viruses to circumvent challenges triggered by the host immune system and resist anti-viral drugs, potentially leading to persistent viral manifestations in host cells. Molnupiravir (RNA-dependent RNA polymerase inhibitor) is a novel anti-viral medicine promising a vital role in coming setbacks.Objectives: This review aims to clarify the safety and efficacy of the molnupiravir molecule in light of existing case studies. As a result, it is intended to explore and discuss the molecular structure, mechanism of action, discovery and development process, preclinical research, clinical investigations, and other subtopics.Methods: A total of 75 publications were searched using multiple engines, such as Google Scholar, PubMed, Web of Science, Embase, Cochrane Library, ClinicalTrials.gov, and others, with a constraint applied to exclude publications published over 11 years ago. Molnupiravir, safety, efficacy, COVID- 19, RdRp, PK-PD, and clinical study were utilized as keywords.Results: Clinical results on molnupiravir are supported by investigations that were recently disclosed in a study on both sex volunteers (male and female) with an age restriction of 19 to 60 years, followed by a Phase-3 Clinical Trial (NCT04575584) with 775 randomly assigned participants and no fatalities reported due to treatment.Conclusion: Molnupiravir proved a high level of safety, allowing it to be tested further. This review supports the safety and efficacy of this molecule based on the established evidence, which claims the most anticipated employment of molnupiravir in COVID protocol.
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To efficiently combat viral infectious diseases, it is important to develop broadly applicable countermeasures, and efficient antiviral systems can be developed by elaborating the relationship of antiviral efficiency with the interactions between antiviral agents and viruses. In the present study, conjugated polymer (CP)-based photodynamic therapy was used to inhibit RNA virus infections. A severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pseudotyped virus composed of an SARS-CoV-2 envelope coated with the S protein and luciferase RNA genome was employed to assess antiviral efficiency. Three cationic CPs with different backbone structures, fluorene-co-phenylene (PFP), thiophene (PMNT), and phenylene vinylene (PPV), exhibit different photoinactivation effects. The highly efficient photoinactivation of PPV and PMNT is derived from the complete photodegradation of spike proteins, nucleocapsid proteins and nucleic acids of SARS-CoV-2 after binding to the viral spike proteins. Although PFP showed the highest efficiency in the photodegradation of spike proteins due to its strong binding affinity, ineffective viral inhibition was observed, which occurred because the viral gene was partially damaged under light irradiation and the process of delivering the viral gene to cells received assistance. This work preliminarily reveals the effect of CP-virus interactions on their photoinactivation activity and should be beneficial for further research on the development of highly efficient antiviral PDT agents.In this work, a photodynamic therapy system based on conjugated polymers (CPs) is developed to inhibit the infection of RNA viruses. Three cationic CPs with different backbone structures fluorene-co-phenylene (PFP), thiophene (PMNT), and phenylene vinylene (PPV) exhibit different photoinactivation effects. PPV and PMNT cause effective inactivation of viruses under light irradiation, while SARS-CoV-2 pseudotyped viruses keep infectious after treated by PFP, which is determined by the interactions between CPs with the proteins and gene of viruses. This work preliminarily reveals the effect of CP-virus interactions on their photoinactivation activity and would be beneficial to develop high-efficient antiviral PDT agents.
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Polymerase chain reaction (PCR)‐based nucleic acid testing has played a critical role in disease diagnostics, pathogen surveillance, and many more. However, this method requires a long turnaround time, expensive equipment, and trained personnel, limiting its widespread availability and diagnostic capacity. On the other hand, the clustered regularly interspaced short palindromic repeats (CRISPR) technology has recently demonstrated capability for nucleic acid detection with high sensitivity and specificity. CRISPR‐mediated biosensing holds great promise for revolutionizing nucleic acid testing procedures and developing point‐of‐care diagnostics. This review focuses on recent developments in both fundamental CRISPR biochemistry and CRISPR‐based nucleic acid detection techniques. Four ongoing research hotspots in molecular diagnostics‐target preamplification‐free detection, microRNA (miRNA) testing, non‐nucleic‐acid detection, and SARS‐CoV‐2 detection‐are also covered.
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IntroductionLife expectancy is increasing worldwide. However, during the COVID-19 pandemic, people 100 years or more (centenaries) were challenged by a potentially fatal disease. We evaluated the outcome of centenaries hospitalized due to COVID-19 in a private healthcare system of Belo Horizonte/Brazil (Unimed-BH).MethodsAdministrative data were collected from the hospital database. Patients were included if they had a severe adult respiratory syndrome due to coronavirus type 2 (SARS-CoV-2) ribonucleic acid identified by quantitative real-time reverse transcriptase polymerase chain reaction (RT-qPCR) or by the International Code of Disease-10th review (ICD-10) hospitalization codes U07.1, B34.2, or B97.2.ResultsFrom March 1 2020 to October 31 2021, 316.4 ± 12.9 centenaries/month were registered. Eighteen hospitalizations due to COVID-19 were identified. Median age was 101.8 years (inter-quartile range [IQR]:100.7,103.0). Most patients were female (83%). There was a median of 6.0 morbidities per patient (IQR:5.3,7.8), range 2-12 morbidities, among 71 possible morbidities. The most described morbidities were systemic arterial hypertension (94%), dementia (61%), and congestive heart failure (61%). Median length of hospitalization was 6.5 days (IQR:3.3,8.0). No patient was dialyzed. Seven (39%) patients died during hospitalization, of whom 3 (17%) were admitted to the Intensive Care Unit and 2 (11%) were oxygenated by invasive mechanical ventilation. No other patients were admitted to the Intensive Care Unit or invasively mechanically ventilated.ConclusionsAlthough the hospitalization rate was low, the mortality rate during hospitalization was high among centenaries. Further research is required to evaluate the actual risks of centenaries to be infected by SARS-CoV-2 and the subsequent outcomes.
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IntroductionThe severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), is a single-strand ribonucleic acid virus that was first identified in January 2020 in patients with viral pneumonia in Wuhan, China. The virus has since spread rapidly around the world, leading the World Health Organization to declare it a pandemic on 11 March 2020. In Brazil there have been 21.8 million cases of SARS-CoV-2 infection and 608,500 deaths. The objective of this study was to evaluate the cost utility of the Oxford, CoronaVac, and Janssen vaccines from the perspective of the Brazilian public health system.MethodsThree microsimulation models were constructed using individual data. The simulations contained seven transition states related to the natural history of COVID-19. The model with a daily cycle had a time horizon of one year and used data from 289 days of the pandemic. The analysis considered direct medical costs from the Brazilian health system perspective. Outpatient, hospital, and mortality databases were used for the model inputs and patient data were stratified by age. Effective vaccines reduced the likelihood of patients becoming ill. Information on the quality of life of patients receiving treatment in the outpatient or hospital setting and disease sequelae were extracted from the published literature. The main outcome of the analysis was quality-adjusted life-years (QALYs).ResultsThe vaccines had incremental cost-utility ratios ranging from USD 4,121 (Oxford) to USD 3,160 per QALY (CoronaVac). The older the population, the lower the incremental cost-utility ratio. Given a willingness-to-pay threshold of BRL 3,129 per QALY, all the vaccines were considered cost effective in the probabilistic sensitivity analysis. The incremental cost-effectiveness ratio stratified by age ranged from USD 6,327 per QALY in patients older than 75 years (Janssen) to USD 20,993 per QALY in patients younger than 59 years (CoronaVac).ConclusionsThe results of this analysis, stratified by patient age, can help in the preparation of a vaccination prioritization plan.
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The global pandemic coronavirus pneumonia（COVID-19）,the disease infected by the new coronavirus（SARS-CoV-2）,is extremely contagious.It is mainly spread among people through respiratory droplets, aerosols, direct or indirect contact, fecal-oral transmission, and cold chain transportation.Especially, patients who are in the incubation period or have no obvious symptoms already have the ability to infect others.SARS-CoV-2 is a positive-sense single-stranded RNA virus, with a single linear RNA segment.Each SARS-CoV-2 virion is 60-140 nm in diameter.Like other coronaviruses, SARS-CoV-2 has four structural proteins, known as the spike（S）, envelope（E）,membrane（M）,and nucleocapsid（N） proteins.To date, a variety of detection methods for the SARS-CoV-2 have been developed based on the virus structural basis and etiological characteristics, which would provide an effective guarantee for the diagnosis of COVID-19 patients and the control of the epidemic.In order to help for the early diagnosis and prevention of COVID-19,the pathogenic characteristics and recent progresses of detection base on nucleic acid, immunology and biosensors of the SARS-CoV-2 are reviewed in this paper.
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IntroductionHepatitis C (HCV) is a blood borne virus that is curative in over 90% of cases. The NHS England HCV Elimination Programme is working to eliminate HCV in advance of the WHO goal of 2030, with initiatives in areas such as primary care, sexual health services and community outreach. High risk groups for HCV include people who inject drugs (PWID), and those who have experienced homelessness. These people tend to be difficult to reach, under-served and at high risk of falling out of the care pathway. During the COVID-19 pandemic, homeless people in a selected small city were housed in empty hostels and hotels. This provided an opportunity for liver specialist nurses (LSNs) to visit these locations, test a high risk population for HCV and commence treatment where necessary.MethodA week-long screening programme has been carried out four times since 2020, led by LSNs and aided by HCV charity workers. Places where high risk groups are known to visit were targeted, including homeless services, hostels and city-centre streets. Rapid HCV antibody tests were used and if positive, further rapid PCR testing was done to detect RNA and distinguish between current and past infection. If RNA was detected, patients were provided with direct-acting antiviral medication.ResultsData from the three most recent weeks of screening were analysed. 354 people were tested. 47 (13.3%) were confirmed HCV RNA positive, 44 (93.6%) of which were commenced on treatment. Reasons that prevented treatment included being unable to contact the patient, death, or contraindications. 22 (6.2%) were identified as having achieved sustained virological response (SVR) from historical antiviral courses. 5 (11.4%) that have been treated during the programme have been confirmed SVR so far. Out of the positives identified, 19 (40.4%) were PWID (current or previous drug injecting), 5 (10.6%) had no history of injecting drugs, and in 23 (48.9%) it was unknown. ConclusionIncreased access to treatment is the lead reason for a reduction in chronic HCV infection among people who inject or have previously injected drugs. This screening programme is benefiting a small city community for those at the highest risk of HCV, and having a positive impact towards the elimination goal. The LSNs are able to visit people who otherwise may be lost from the care pathway. By being able to revisit the same locations each time, HCV positive people are being treated and receiving appropriate follow-up care.
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Background: SARS-CoV-2 has paralyzed mankind due to its high transmissibility and its associated mortality, causing millions of infections and deaths worldwide. The search for gene expression biomarkers from the host transcriptional response to infection may help understand the underlying mechanisms by which the virus causes COVID-19. This research proposes a smart methodology integrating different RNA-Seq datasets from SARS-CoV-2, other respiratory diseases, and healthy patients. Methods: The proposed pipeline exploits the functionality of the ‘KnowSeq’ R/Bioc package, integrating different data sources and attaining a significantly larger gene expression dataset, thus endowing the results with higher statistical significance and robustness in comparison with previous studies in the literature. A detailed preprocessing step was carried out to homogenize the samples and build a clinical decision system for SARS-CoV-2. It uses machine learning techniques such as feature selection algorithm and supervised classification system. This clinical decision system uses the most differentially expressed genes among different diseases (including SARS-Cov-2) to develop a four-class classifier. Results: The multiclass classifier designed can discern SARS-CoV-2 samples, reaching an accuracy equal to 91.5%, a mean F1-Score equal to 88.5%, and a SARS-CoV-2 AUC equal to 94% by using only 15 genes as predictors. A biological interpretation of the gene signature extracted reveals relations with processes involved in viral responses. Conclusion: This work proposes a COVID-19 gene signature composed of 15 genes, selected after applying the feature selection ‘minimum Redundancy Maximum Relevance’ algorithm. The integration among several RNA-Seq datasets was a success, allowing for a considerable large number of samples and therefore providing greater statistical significance to the results than in previous studies. Biological interpretation of the selected genes was also provided.
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The development of a cost-efficient device to rapidly detect pandemic viruses is paramount. Hence, an innovative and scalable synthesis of metal nanoparticles followed by its usage for rapid detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been reported in this work. The simple synthesis of metal nanoparticles utilizing tin as a solid-state reusable reducing agent is used for the SARS-CoV-2 ribonucleic acid (RNA) detection. Moreover, the solid-state reduction process occurs faster and leads to the enhanced formation of silver and gold nanoparticles (AuNPs) with voltage. By adding tin as a solid-state reducing agent with the precursor, the nanoparticles are formed within 30 s. This synthesis method can be easily scaled up for a commercially viable process to obtain different-sized metal nanoparticles. This is the first disclosure of the usage of tin as a reusable solid-state reducing agent for metal nanoparticle synthesis. An electronic device, consisting of AuNPs functionalized with a deoxyribonucleic acid (DNA)-based aptamer, can detect SARS-CoV-2 RNA in less than 5 min. With an increase in SARS-CoV-2 variants, such as Delta and Omicron, the detection device could be used for identifying the nucleic acids of the COVID-19 variants by modifying the aptamer sequence. The reported work overcomes the drawbacks of complex instrumentation, trained labor, and increased turnaround time.
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Introduction: The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), identified in December of 2019, is the cause of the coronavirus disease 2019 (COVID-19). Due to the high reproductive rate of the virus, the best way to slow down the spread is to identify and isolate patients at the early stage of infections. The current diagnostic methods are either too expensive, slow or have low accuracy. Variants of SARS-CoV-2 with mutations at the primer binding sites may cause evasion of polymerase chain reaction (PCR) detection using current primers. Reverse transcription loop-mediated isothermal amplification (RT-LAMP) has potential as a rapid molecular test that is easy to conduct. Methods: LAMP primers were design based on the highly conserved regions of the SARS-CoV-2 Nucleocapsid (N) gene. RT-LAMP assays were conducted using an optimized Bst 3.0 polymerase protocol on T7 RNA polymerase synthesized RNA template. The LAMP sensitivity assay was tested on 1:10 serial diluted pJET1.2 vector with SARSCoV2 N gene inserts. A specificity test was conducted by running the test on plasmids containing SARS-CoV and MERS-CoV N genes. The results were visualised via gel electrophoresis, SYBR Green staining and Lateral Flow Dipstick (LFD). Results: The optimized protocol is sensitive enough to detect SARS-CoV-2 genetic material within 10 minutes but is most sensitive at 30 minutes. Additionally, it is specific to only the genetic materials of SARS-CoV-2. Furthermore, an LFD with multiple test lines was successful for multiplexed LAMP reactions with different genic regions of the virus. Conclusion: The multiplexed LFD-LAMP is potentially a simple yet specific and sensitive method of rapid molecular diagnostics of COVID-19.
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BackgroundSince the COVID-19 outbreak emerged, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has continuously evolved into variants with underlying mutations associated with increased transmissibility, potential escape from neutralizing antibodies, and disease severity. Although intensive research is ongoing worldwide to understand the emergence of SARS-CoV-2 variants, there is a lack of information on what constitutes the expressed RNA variants in critical and non-critical comorbidity-free young patients. The study sought to characterize the expressed RNA variants from young patients with critical and non-critical forms of SARS-CoV-2 infection.MethodologyThe bulk ribonucleic acid (RNA) sequencing data with the identifier GSE172114 were downloaded from the Gene Expression Omnibus (GEO) database. The study participants were divided into critical, n = 46, and non-critical, n = 23. FastQC version 0.11.9 and Cutadapt version 3.7 were used to assess the read quality and perform adapter trimming, respectively. Spliced Transcripts Alignment to a Reference (STAR) version 2.7.10a was used to align reads to the human (hg38) reference genome. Genome Analysis Tool Kit (GATK) best practice was followed to call variants using the rnavar pipeline, part of the nf-core pipelines.ResultsOur research demonstrates that critical and non-critical SARS-CoV-2-infected individuals are characterized by a unique set of expressed RNA variants. The expressed gene variants are enriched on the innate immune response, specifically neutrophil-mediated immune response. On the other hand, the expressed gene variants are involved in both innate and cellular immune responses.ConclusionDeeply phenotyped comorbidity-free young patients with critical and non-critical SARS-CoV-2 infection are characterized by a unique set of expressed RNA variants. The findings in this study can inform the patient classification process in health facilities globally when admitting young patients infected with SARS-CoV-2.
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Surveillance of municipal wastewater for RNA of SARS-CoV-2, the causative agent of coronavirus disease (COVID-19), is well documented around the world. However, unlike most countries where wastewater surveillance was initially employed during 2020, New Zealand was in the fortunate position of having very few COVID-19 cases, generally confined to Managed Isolation and Quarantine facilities. As such, the prevalence of SARS-CoV-2 RNA in wastewater was likely much lower than seen in other countries. A nine-week pilot study was undertaken to assess the feasibility of detecting SARSCoV-2 RNA in wastewater in New Zealand. Wastewater from 18 catchments across New Zealand was monitored, including six that contained Managed Isolation and Quarantine facilities. Testing both in regions known to have COVID-19 cases and regions where detection was not expected (catchments not containing Managed Isolation and Quarantine facilities) allowed the sensitivity and specificity of detection methods to be assessed. SARS-CoV-2 RNA was detected in seven out of the nine weeks of this study in the Auckland South Western Interceptor catchment, which contained a dedicated isolation facility to which confirmed cases from Auckland, Hamilton and Rotorua were transferred. In weeks two and three of sampling, SARS-CoV-2 RNA was detected in the Christchurch catchment. This coincided with up to 14 COVID-19 cases likely to be shedding high levels of virus (PCR Cq value < 20) in the Managed Isolation and Quarantine facilities. Samples from the seven other weeks were negative despite up to 35 infected cases present at any one time. However, on any of these test dates eight cases or fewer had a PCR Cq value < 30 and were within 10 days of symptom onset or positive PCR test date. Sample inhibition and non-specificity were not observed to be issues. The results of this pilot study underpinned recommendations that wastewater monitoring for SARS-CoV-2 RNA be incorporated as a surveillance tool in New Zealand's COVID-19 response.
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Coronavirus disease or COVID-19 is a virus from the Coronaviridae family that has caused pandemics throughout the world since the end of 2019. The virus spreads ten times faster through human interaction than SARS-CoV. The RNA sequence of COVID-19 has a 79.5% similarity with SARS-CoV. Fast and specific detection of COVID-19 is needed so that patient detection can be done quickly and accurately. One method that can be developed as a COVID-19 biosensor is aptamers-based biosensors. The aptamer is an artificial oligo nucleic acid that can specifically bind to target molecules. The aptamer is easily and chemically modifiable for increasing stability and reducing toxicity. It shows a comparable affinity for the target virus and better thermal stability than monoclonal antibodies. This advantage makes aptamer a promising candidate in diagnostic and detection applications. The goal of this research is to use an RNA aptamer as the specific recognition element in a portable surface plasmon resonance (SPR) biosensor for the detection of COVID-19 in humans. An aptamer RNA 1 COVID-19 was designed using the COVID-19 sequence from GISAID using the in silico method. End of 3’ aptamer RNA 1 was modified with dithiol. And Then, the aptamer was immobilized on the gold nanoparticle sensor surface via Cysteine-dithiol binding. The RNA solution, that had been extracted from swab samples, was diluted ten times before being used as a sample. The immobilized aptamer RNA 1 captured COVID-19 in RNA solution, causing an increase in refraction index (r.u). An aptamer RNA 1 was found to bind RNA virus of COVID-19 where the positive sample of COVID-19 has refraction index (r.u) between 3 r.u – 10 r.u for various Ct values.
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Background: Free-of-charge HCV screening in some key populations and in 1969–1989 birth cohorts has been funded in Italy as the first step to diagnosing individuals who are infected but asymptomatic. The aim of this study is to evaluate the feasibility of an opportunistic HCV screening and its linkage to care. Methods: A hospital-based HCV screening was conducted as a routine test for in-patients admitted to the Evangelical Hospital Betania of Naples from January 2020 to May 2021. All consecutive in-patients were screened for the HCV antibody (HCV-Ab) at the time of their admission to the hospital, and those born prior to year 2000 were included in the study. HCV-RNA testing was required for those not previously treated and without antiviral treatment contraindications. For in-patients with an active infection, treatment started soon after hospital admission. Results: Among 12,665 inpatients consecutively screened, 510 (4%) were HCV-Ab positive. The HCV-Ab positivity rate increased with age, reaching the highest prevalence (9.49%) in those born before 1947. Among patients positive for HCV, 118 (23.1%) had been previously treated, 172 (33.9%) had been discharged before being tested for HCV-RNA, and 26 (5.1%) had not been tested for short life expectancy. Of 194 (38% of HCV-Ab+) patients who were tested for HCV-RNA, 91 (46.2%) were HCV-RNA positive. Of patients with active infection, 33 (36%) were admitted to the liver unit with signs of liver damage either not previously diagnosed or diagnosed but unlinked to care for HCV infection. Of the patients positive for HCV-RNA, 87 (95.6%) started treatment;all achieved sustained virological response. Conclusion: HCV active infection has been frequently found in patients with comorbidities admitted in the hospital in Southern Italy. To achieve HCV elimination in Italy, broader screening strategies are required. In addition to screening of the 1969–1989 birth cohort of individuals unaware of their infection status, diagnosis and linkage to care of patients with known liver damage is strictly required. Hospital screening is feasible, but prompt reflex testing for identifying HCV-active infections is necessary to increase diagnosis and subsequent linkage to care.
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MicroRNAs have been projected as promising tools for diagnostic and prognostic purposes in cancer. More recently, they have been highlighted as RNA therapeutic targets for cancer therapy. Though miRs perform a generic function of post-transcriptional gene regulation, their utility in RNA therapeutics mostly relies on their biochemical nature and their assembly with other macromolecules. Release of extracellular miRs is broadly categorized into two different compositions, namely exosomal (extracellular vesicles) and non-exosomal. This nature of miRs not only affects the uptake into target cells but also poses a challenge and opportunity for RNA therapeutics in cancer. By virtue of their ability to act as mediators of intercellular communication in the tumor microenvironment, extracellular miRs perform both, depending upon the target cell and target landscape, pro- and anti-tumor functions. Tumor-derived miRs mostly perform pro-tumor functions, whereas host cell- or stroma-derived miRs are involved in anti-tumor activities. This review deals with the recent understanding of exosomal and non-exosomal miRs in the tumor microenvironment, as a tool for pro- and anti-tumor activity and prospective exploit options for cancer therapy.
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BackgroundDuring the current severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) pandemic, computed tomography (CT) has become widely used in patients with suspected or known coronavirus disease 2019 (COVID-19). This prospective observational study in 28 invasively ventilated and 18 non-invasively ventilated patients with confirmed SARS-CoV-2 contamination aims at investigating SARS-CoV-2 contamination of CT scanner surfaces and its infectiousness.MethodsSwab sampling of the CT table and gantry before and after CT examinations was performed. Additionally, the CT ventilation system air grid was wiped off after each examination. Real-time reverse-transcription polymerase chain reaction (RT-PCR) for SARS-CoV-2 RNA (ribonucleic acid) and viral cell culture were performed in the virology core lab.ResultsAfter examination of non-invasively ventilated or non-ventilated patients, SARS-CoV-2 RNA was found in 11.1% (4/36) on patient near surfaces (CT table and gantry) and in 16.7% (3/18) on the CT air grid respectively after examination of invasively ventilated patients in 5.4% (3/56) on CT table and gantry and 7.1% (2/28) on the CT air grid. Surface contamination was more common in non-invasively ventilated or non-ventilated patients with a high viral load who were actively coughing. RT-PCR cycle threshold (Ct) was high (35.96–39.31) in all positive samples and no positive viral cell culture was found.ConclusionOur study suggests that CT scanner surface contamination with SARS-CoV-2 is considerable and more common after examination of non-invasively ventilated or non-ventilated patients compared to invasively ventilated patients. However, no viral cell culture positivity was found, hence the infectious potential seems low.