Detection of COVID-19 DNA using Förster Resonance Energy Transfer between upconversion and gold nanoparticles

FRET is ascribed to the spectral overlapping of upconversion luminescence and the absorption of AuNPs. This experiment enables early-stage coronavirus detection. The results show a sensitivity of 100 fM for the detection of COVID-19 DNA. © 2022 The Author(s)

Detection of COVID-19 DNA using Förster Resonance Energy Transfer between upconversion and gold nanoparticles

FRET is ascribed to the spectral overlapping of upconversion luminescence and the absorption of AuNPs. This experiment enables early-stage coronavirus detection. The results show a sensitivity of 100 fM for the detection of COVID-19 DNA. © 2022 The Author(s)

Impaired exercise capacity in post-COVID syndrome: The role of VWF-ADAMTS13 axis

Background: Post-COVID syndrome (PCS) is an increasingly recognised complication of acute SARS-CoV- 2 infection, characterised by persistent fatigue, reduced exercise tolerance, chest pain, shortness of breath and cognitive slowing. Acute COVID-19 is strongly linked with increased risk of thrombosis;a prothrombotic state. Elevated Von Willebrand Factor (VWF) Antigen (Ag):ADAMTS13 ratio is associated with severity of acute COVID-19 infection. Aim(s): We hypothesised that the pro-thrombotic state is implicated in the pathogenesis of PCS. We investigated specialist coagulation parameters associated with reduced exercise capacity in patients with PCS to identify the utility of these parameters to determine ongoing disease activity. We also investigated if an association exists between elevated VWF(Ag):ADAMTS13 ratio and impaired exercise capacity in patients with PCS. Method(s): Retrospective analysis of VWF(Ag):ADAMTS13 ratio in patients with PCS at a dedicated post-COVID clinic. VWF(Ag):ADAMTS13 ratio was correlated with symptoms including exercise capacity as assessed by 1 minute sit-to- stand (STS) test and/or 6 minute walk test (6MWT). Peripheral oxygen desaturation >=3% for 6MWT and STS test, and increase in lactate>1 from baseline during 6MWT were taken as markers of impaired exercise capacity. Result(s): Elevated VWF(Ag):ADAMTS13 ratio (>=1.5) was found to be four times (OR 4.3) more likely in patients with impaired exercise capacity. 20% (56/276) had impaired exercise capacity, of which 55% (31/56) had a raised VWF(Ag):ADAMTS13 ratio >=1.5 (p < 0.0001). A higher median VWF(Ag):ADAMTS13 ratio of 1.5 (IQR 1.2-1.7) in patients with abnormal exercise testing compared to 1.1 (IQR 0.9-1.4) in patients with normal exercise testing was found (p < 0.0001). FVIII and VWF(Ag) were elevated in 26% and 18% respectively and support a hypercoagulable state in patients with PCS. Conclusion(s): These findings suggest possible ongoing microvascular/ endothelial dysfunction in the pathogenesis of PCS and highlight the potential role for prophylactic anticoagulation in the management of these patients.

Long Covid: Evidence of Persistent Abnormalities in Thrombotic Markers and Correlation with Functional Impairment

Rationale: SARS-CoV-2 infection has been recognised to cause endotheliitis and a pro-thrombotic state during acute illness. Following acute infection, a phenomenon described as 'Long COVID' can cause persisting morbidity with multiple symptoms including exercise intolerance. In recent months preliminary data has proposed persistence of micro-clots as a mechanism for Long COVID. We sought to further understand if a thromboinflammatory processes could be contributing to clinical phenotypes in patients assessed in a UK Post COVID service. Methods: Retrospective analysis of real-world electronic health data relating to patients attending between May 2020 and Jan 2022 (both post hospital and community managed). D-dimer levels, Von Willebrand Factor antigen (vWFAg), date of acute COVID infection and attendance source were available in 1607 patients (1163 community managed and 444 post hospitalisation with acute SARS-CoV-2). vWFAg: ADAMTS13 ratio was reviewed in a subset of 329 patients and correlated with symptoms and functional assessments such as the 6 minute walk test and/or 1 minute sit-tostand test. vWF(Ag):ADAMTS13 ratio was also calculated on 50 voluntary normal controls (Medical Research Ethics Committee Numbers 08/H0810/54 and 08/H0716/72). Results: In the overall cohort D-dimer and vWF(Ag) levels were mostly in the normal range. However, in post-hospitalised patients 21/90 (23.3%) and 65/500(11.5%) community-managed patients had a D-dimer > 550mg/L more than 180 days from acute infection (figure 1). vWF(Ag) levels showed a similar spectrum of abnormalities. In the subgroup with vWF(Ag):ADAMTS13 ratios analysis, 70 (21%) had evidence of abnormal exercise testing as confirmed by desaturation ≥3% and/or an increase in lactate levels >1 above baseline. 43 (61%) of this group had elevated vWF(Ag):ADAMTS13 >1.5. Abnormal exercise testing was associated with a higher vWF(Ag):ADAMTS13 with a median of 1.5 (IQR 1.2-1.7) compared with 1.2 (IQR 0.9-1.4) in those with normal exercise test (p<0.0001), OR 4.955 [2.850-8.612], p<0.0001). Conclusions: This cohort of patients demonstrates a subgroup with persistently elevated D-dimer and vWFAg levels suggesting these markers of thromboinflammatory processes could be of relevance in defining phenotypes within long COVID. The spectrum of abnormality seen, together with the observed correlation of vWF(Ag): ADAMTS13 ratios with impaired exercise tolerance warrants further evaluation of microvascular/ endothelial dysfunction as a mechanism in Long COVID. Further mechanistic studies are in progress.

A fiber optic-nanophotonic approach to the detection of antibodies and viral particles of COVID-19

Dr. Deborah Birx, the White House Coronavirus Task Force coordinator, told NBC News on "Meet the Press" that "[T]he U.S. needs a 'breakthrough' in coronavirus testing to help screen Americans and get a more accurate picture of the virus' spread." We have been involved with biopathogen detection since the 2001 anthrax attacks and were the first to detect anthrax in real-time. A variation on the laser spectroscopic techniques we developed for the rapid detection of anthrax can be applied to detect the Severe Acute Respiratory Syndrome-Corona Virus-2 (SARS-CoV-2 virus). In addition to detecting a single virus, this technique allows us to read its surface protein structure. In particular, we have been conducting research based on a variety of quantum optical approaches aimed at improving our ability to detect Corona Virus Disease-2019 (COVID-19) viral infection. Indeed, the detection of a small concentration of antibodies, after an infection has passed, is a challenging problem. Likewise, the early detection of disease, even before a detectible antibody population has been established, is very important. Our team is researching both aspects of this problem. The paper is written to stimulate the interest ofboth physical and biological scientists in this important problem. It is thus written as a combination of tutorial (review) and future work (preview). We join Prof. Federico Capasso and Editor Dennis Couwenberg in expressing our appreciation to all those working so heroically on all aspects of the COVTD-19 problem. And we thank Drs. Capasso and Couwenberg for their invitation to write this paper. © 2021 Walter de Gruyter GmbH, Berlin/Boston. All rights reserved.

Business premises capacity manager project for covid compliance using Android applications with geolocation services

The global pandemic has affected how restaurants and other businesses provide service to their customers. This is especially true of the hospitality industry. Customers are wary of visiting businesses due to crowds and adherence to covid 19 regulations, which requires businesses to operate at a certain capacity to ensure social distancing is followed. The solutions to these problems should be done in such a way that customers of the hospitality industries etc. are able to choose and attend premises knowing that capacity and social distancing is being followed. Results will show this using mobile app technology, with real-time information from businesses on their capacity. There is a gap in the research as the global pandemic has only happened recently. We have exhibited an open-source application to aid customers and businesses in the social distancing era.. © 2021 IEEE.

Response of tertiary addictions services to opioid dependence during the COVID-19 pandemic.

The emergence of the COVID-19 pandemic has presented the addiction services with an unprecedented set of challenges. Opioid users are particularly vulnerable because of their high level of pre-existing health problems and lifestyle factors. In order to minimise their risks to self and to others in the current Covid-19 crisis, addiction services sought to urgently identify vulnerable individuals, and induct them into opioid substitution treatment (OST) promptly. Additionally, several guidelines were created and regularly updated by the health and safety executive (HSE) for any healthcare staff working with opioid users. These include guidance documents, to facilitate prompt induction of patients onto the OST programme, the prescribing of naloxone to all patients at risk of overdose, eConsultation, medication management for those in self-isolation, and the delivery of injecting equipment. The guidance documents and resources will provide a template for a new way of working for the sector during these challenging times and into the future.

Laboratory biomarkers associated with COVID-19 severity and management.

The heterogeneous disease course of COVID-19 is unpredictable, ranging from mild self-limiting symptoms to cytokine storms, acute respiratory distress syndrome (ARDS), multi-organ failure and death. Identification of high-risk cases will enable appropriate intervention and escalation. This study investigates the routine laboratory tests and cytokines implicated in COVID-19 for their potential application as biomarkers of disease severity, respiratory failure and need of higher-level care. From analysis of 203 samples, CRP, IL-6, IL-10 and LDH were most strongly correlated with the WHO ordinal scale of illness severity, the fraction of inspired oxygen delivery, radiological evidence of ARDS and level of respiratory support (p ≤ 0.001). IL-6 levels of ≥3.27 pg/ml provide a sensitivity of 0.87 and specificity of 0.64 for a requirement of ventilation, and a CRP of ≥37 mg/l of 0.91 and 0.66. Reliable stratification of high-risk cases has significant implications on patient triage, resource management and potentially the initiation of novel therapies in severe patients.

A fiber optic-nanophotonic approach to the detection of antibodies and viral particles of COVID-19

Dr. Deborah Birx, the White House Coronavirus Task Force coordinator, told NBC News on "Meet the Press"that "[T]he U.S. needs a 'breakthrough' in coronavirus testing to help screen Americans and get a more accurate picture of the virus' spread."We have been involved with biopathogen detection since the 2001 anthrax attacks and were the first to detect anthrax in real-time. A variation on the laser spectroscopic techniques we developed for the rapid detection of anthrax can be applied to detect the Severe Acute Respiratory Syndrome-Corona Virus-2 (SARS-CoV-2 virus). In addition to detecting a single virus, this technique allows us to read its surface protein structure. In particular, we have been conducting research based on a variety of quantum optical approaches aimed at improving our ability to detect Corona Virus Disease-2019 (COVID-19) viral infection. Indeed, the detection of a small concentration of antibodies, after an infection has passed, is a challenging problem. Likewise, the early detection of disease, even before a detectible antibody population has been established, is very important. Our team is researching both aspects of this problem. The paper is written to stimulate the interest of both physical and biological scientists in this important problem. It is thus written as a combination of tutorial (review) and future work (preview). We join Prof. Federico Capasso and Editor Dennis Couwenberg in expressing our appreciation to all those working so heroically on all aspects of the COVID-19 problem. And we thank Drs. Capasso and Couwenberg for their invitation to write this paper. © 2020 Navid Rajil et al., published by De Gruyter, Berlin/Boston 2020.

Photonic toolbox for fast real-time polymerase chain reaction

We present an optical scientist vision for a photonic platform for real-time polymerase chain reaction (qPCR) and reverse-transcription qPCR (qRT-PCR) that integrates a rapid-cycle fiber-optic PCR chamber with feedback-controlled laser heating, online fluorometric detection of PCR products, and all-optical thermometry using an optical readout from color centers of diamond nanoparticles. We show that, with a careful optimization of laser-induced heating and heat-removal geometry, this approach can radically shorten the qPCR thermal cycle relative to standard PCR systems, paving the way toward credit-card-size testing kits for fast point-of-care infection diagnosis. Faster photonic qPCR/qRT-PCR will enable a rapid and highly specific early detection of infections, including new viruses, such as SARS-CoV-2 at very early stages-in most cases, even before the onset of disease, providing much-needed lead time for early treatment and disease spread prevention.