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1.
Journal of Saudi Chemical Society ; 26(5), 2022.
Article in English | Web of Science | ID: covidwho-2069403

ABSTRACT

Synthesis and structural characterization of nano crystallites of bis-violurate-based manganese(II) and copper(II) chelates is the subject of the present study. Analytical data and mass spectra as well as thermal analysis determined the molecular formulas of the present metal chelates. Spectroscopic and magnetic measurements assigned the structural formula of the present violurate metal complexes. The spectroscopic and magnetic investigations along with structural analysis results indicated the square planar geometry of both the Mn(II) and Cu(II) complexes. The structural analysis of the synthesized metal complexes was achieved by processing the PXRD data using specialized software Expo 2014. Spectrophotometeric and viscosity measurements showed that violuric acid and its Mn(II) and Cu(II) complexes successfully bind to DNA with intrinsic binding constants Kb from 38.2 x 105 to 26.4 x 106 M-1. The antiviral activity study displayed that the inhibitory concentrations (IC50) of SARS-CoV-2 by violuric acid and its Mn(II) and Cu(II) complexes are 84.01, 39.58 and 44.86 lM respectively. Molecular docking calculations were performed on the SARS-CoV-2 virus protein and the computed binding energy values are -0.8, -3.860 -5.187 and -4.790, kcal/mol for the native ligand, violuric acid and its Mn(II) and Cu(II) complexes respectively. Insights into the relationship between structures of the current compounds and their degree of reactivity are discussed.(c) 2022 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

2.
Environmental Science & Technology ; 44(8):82-90, 2021.
Article in Chinese, English | CAB Abstracts | ID: covidwho-2056700

ABSTRACT

In order to trace and monitor the atmospheric heavy metal pollution in Xichang City, an investigation activity was carried out with a sort of moss (Taxiphyllum taxirameum) (packed in moss bags) as a biological indicator for monitoring heavy metal pollution. The investigation was conducted from the period from April 2019 to April 2020, during which two grave emergency events occurred during spring monitoring period from January 15 to April 15, 2020, i.e., COVID-19 and "3.30"severe forest fire in Xichang, which inevitably affected the atmospheric quality. Based on the concentration analysis of 12 kinds of heavy metal, including Al, Cr, Fe, Cu, Ni, Pb, Mn, Hg, Zn, V, As and Ba contained in the moss and the local meteorological data, comparing those informative data before and after the time when the emergency events toke place, the paper made an analysis on the impacts of two enormous emergency events on the air pollution of heavy metal in Xichang. The results showed that total amount of enrichment of above-mentioned 12 heavy metals in spring (January 15 to April 15, 2020) is (12.85 +or- 1.57) mg/g, which was significantly higher than in the other three seasons (p < 0.01), but no significant discrepancies about the total enrichment amount in the other three seasons (p > 0.05). Primarily because of COVID-19 pandemic, the level of motor vehicles emissions cut down, and the decrease of the tourism in the related areas perhaps causing the decline of pollution of Pb. In addition, the decrease of unbalanced emission of pollutants led to a noted increase of atmospheric oxidation in urban area, thus boosting the formation of secondary particulate matter, and the particulate matter from surrounding industrial sources was transported into the urban area;as a result, remarkable increases of Hg concentration of moss within the moss bags were detected downwind the industrial area located in the urban fringe. Consequently, the investigation showed that the moss-bag method is an effective biological tool for monitoring air heavy metal pollution, which could reflect the impacts of major pollution events on air quality.

3.
International Journal of Energy Research ; : 1, 2022.
Article in English | Academic Search Complete | ID: covidwho-2034776

ABSTRACT

Summary In the novel coronavirus epidemic, Russia–Ukrainian war environment, oil, and other energy resources are in short supply. With the increase of oil prices, electric vehicles become mainstream vehicles. As the core component of electric vehicles, batteries have become an integral part of people's daily life. The development of high‐performance, pollution‐free batteries has become the focus of the world. Because of the advantages of high specific capacity, environmental friendliness and low cost, ternary cathode material have become a research hotspot of lithium‐ion batteries. This paper mainly selects high nickel ternary material as the research object, and from its working principle, composition structure, material preparation, reaction mechanism, existing problems, and modification method to six aspects of a more comprehensive overview, for future researchers to provide a beneficial reference. [ FROM AUTHOR] Copyright of International Journal of Energy Research is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

4.
Green Chemistry ; 2022.
Article in English | Web of Science | ID: covidwho-2016864

ABSTRACT

As the economy started to recover from the COVID pandemic, the price of Li2CO3 skyrocketed to its highest. This situation has aggravated concerns about the supply chain for lithium-ion batteries (LIBs). Recycling spent LIBs is a potential solution to alleviate the bottleneck of the supply chain and prevent environmental pollution, and has attracted lots of attention. However, lithium recycling is generally disregarded because of the complex recycling process and its low recycling efficiency. Here, in this work we developed a sustainable lithium recovery process, which can selectively leach and recover lithium with formic acid before recycling valuable metals. With the reported method, lithium can be 99.8% recovered from layered oxide cathode materials with 99.994% purity. In addition, this lithium recovery process is affordable, compared to the typical hydrometallurgical process, by saving 11.15% per kilogram of spent LIBs. Therefore, this research provided a new solution to eliminating the effects of lithium ions on valuable metal separation and the co-precipitation reaction and precluding the influence of other metal ions on lithium recovery. This simplified lithium recovery process provides new opportunities for sustainable recycling of LIBs and economical restoration of the lithium supply chain.

5.
Journal of Electroanalytical Chemistry ; : 116745, 2022.
Article in English | ScienceDirect | ID: covidwho-2004211

ABSTRACT

A molecularly imprinted electrochemical sensor was fabricated for sensitive and selective detection of anti-COVID 19 drug favipiravir (FAV). The sensor is based on the synthesis of biomass-derived carbon (BC) and nickel disulfide nanospheres (NiS2 NS), which were used to decorate glassy carbon electrode (GCE). Then, the gold nanoparticles (AuNPs) were electro- deposited on the surface of NiS2 NS/BC/GCE to enhance conductivity, increase electron transfer, and aid polymerization of p-aminothiophenol (p-ATP) functional monomer. The fabrication steps were characterized using different morphological and electrochemical techniques. Variables affecting the formation of molecularly imprinted layers and the determination of FAV were optimized. Under optimum conditions, the oxidation current (Ipa) was increased upon addition of FAV in the range of 0.42-1100 nM with a limit of detection (LOD, S/N) of 0.13 nM. The as-fabricated sensor possesses several advantages such as high sensitivity and selectivity, good reproducibility, and acceptable stability. Furthermore, the proposed molecularly imprinted –based electrochemical sensor was efficiently applied for the determination of FAV in tablets and human serum samples with recoveries % of 99.2 to 102.1 % and RSDs % in the range of 2.4-3.2 %, which confirms the reliability of the sensor to detect FAV in different matrices.

6.
Applied Sciences ; 12(15):7586, 2022.
Article in English | ProQuest Central | ID: covidwho-1993926

ABSTRACT

Eastern Indonesia, including the island of Halmahera, is a region with a high mineral potential, particularly Ni-Co, Au-Cu, and Ag ores, which are a globally important and critical source of raw materials (CRMs). The research was conducted within the framework of scientific cooperation between the Faculty of Geology, University of Warsaw (Poland), and PT Halmahera Resources Percasa Ltd. (Jakarta, Indonesia) Between the years of 2009 and 2011, 42 boreholes were drilled using an impact system (up to 15 m below surface) and 3 test pits (up to 8 m below surface). The presence of a laterite deposit containing Ni-Co mineralization was identified on the license area. The resources estimated in accordance with JORC Code, with a cut-off grade Ni ≥ 0.5%, equaling 185,510 t Ni and 17,747 t Co, with the stock of raw material amounting to 14.8 million t and with an average content of 1.00% Ni and 0.13% Co. The ore in the deposit has mixed character. To date, studies have shown the dominance of oxide ore, but saprolite composed of magnesium silicates was also identified in significant amount. The Ni mineralization in oxide ore (limonite) is bound to goethite and manganese minerals, while in the case of silicate (saprolite) ore, it occurs locally in the form of veins as well as zonally in the weathered serpentinites. Cobalt mineralization is almost entirely related to the Mn minerals that occur in the lower oxide zone. It has been found that both serpentinites and harzburgites (and possibly locally lherzolite) are the parent rocks for laterite deposit.

7.
Sustainability ; 14(7), 2022.
Article in English | CAB Abstracts | ID: covidwho-1924307

ABSTRACT

River water quality is a serious concern among scientist and government agencies due to increasing anthropogenic activities and uncontrolled industrial discharge to rivers. The present study was conducted near the river mouth of the Kerian River to assess heavy metal pollution during COVID-19 pandemic-lockdown conditions and post-COVID-19 pandemic-unlock conditions. Twelve samples of shallow, middle, and bottom depths were collected at four locations along a 9.6 km reach. A concentration of eight heavy metals including Cadmium, Chromium, Copper, Iron, Manganese, Nickel, Lead, and Zinc were extracted through atomic absorption spectrometry. Total suspended solid was measured during laboratory experimentation. The results showed that, during the pandemic, concentrations of Nickel, Zinc, and Iron were high at shallow, middle, and bottom depths, respectively. Decreasing orders of heavy metal concentration are variable at different depths due to either their high sinking tendency with other existing components of water matrix or the anthropogenic source. However, almost all values of heavy metals are under the permissible limit of National Water Quality Standards of Malaysia and Food and Drug Administration. A possible reason for the lack of heavy metal pollution may be the restriction of anthropogenic activities during the COVID-19 pandemic. Additionally, no significant differences were observed in total suspended solid.

8.
Journal of Urology ; 207(SUPPL 5):e1044-e1045, 2022.
Article in English | EMBASE | ID: covidwho-1886529

ABSTRACT

INTRODUCTION AND OBJECTIVE: SARS-CoV-2 can invade different testicular cell types, such as spermatogonia, spermatids, Sertoli, and Leydig cells. We investigated the viral presence inside the sperm of negative PCR infected men up to 3 months after discharge from the hospital. METHODS: This cross-sectional study included 13 of a 26 moderate-to-severe SARS-CoV-2 infected men cohort (mean 34.3 ± 6.5 years;range: 21-50 years old). Patients were enrolled 30 to 90 days after the diagnosis. Semen samples were obtained by masturbation and processed within one hour according to WHO guidelines. All patients were PCR negative for the virus in the ejaculate. Samples were liquefied for 30 min at room temperature in 0.1M phosphate buffer before centrifuging at 500 g for 10 min. The supernatant was removed, and pellets were fixed in 2,5% v/v glutaraldehyde in 0.1M phosphate buffer for 2h at 4°C, post-fixed in 1% OsO4 for 1h at 4°C, stained overnight in 1% aqueous uranyl acetate. Then, the pellets were dehydrated sequentially in 30%, 70%, and 100% ethanol and embedded in epoxy resin. Ultrathin sections (70nm) were obtained in an ultramicrotome, collected on nickel grids, and double-stained by uranyl acetate and lead citrate. Micrographs were obtained with a Jeol JEM 1010 electron microscope (Tokyo, Japan, 80 kV). RESULTS: We identified viruses inside spermatozoa in 9/13 patients up to 90 days after discharge from the hospital. Moreover, in all 13 men, a type of DNA-based extracellular traps, probably in a cfDNAdependent manner, like described in the COVID-19 systemic inflammatory response. FIGURE: High magnification electron micrograph of a spermatozoon with the nucleus (nu) displaying the typical condensed chromatin. The remained cytoplasm contains several viral particles (ranging in diameter from 90 to 110 nm). The inset corresponds to a higher magnification of the boxed area containing two virions, showing the SARS-CoV-2 characteristics: viral envelope (white arrowhead), nucleocapsids (black arrowhead), and spike-like projections (white arrow). CONCLUSIONS: Although SARS-CoV-2 is not found in the infected men's semen, it was intracellularly present in the spermatozoa. The potential implications for assisted conception should be addressed. (Figure Presented).

9.
The Science Teacher ; 88(6):6-7, 2021.
Article in English | ProQuest Central | ID: covidwho-1857444

ABSTRACT

Whether through creative uses of cell phone technology, makeshift lab equipment, or the use of virtual laboratory and virtual field trip events, our students were able to experience science in new and powerful ways. Science teachers adapted and shared their ideas, using social media groups such as Facebook's "NGSS Chemistry Teachers," "NGSS Biology Teachers," and other science teaching groups. All COVID-19 vaccines are free from metals such as iron, nickel, cobalt, lithium, and rare earth alloys, as well as any manufactured products such as microelectronics, electrodes, carbon nanotubes, and nanowire semiconductors.

10.
International Journal of Environmental Research and Public Health ; 19(9):5773, 2022.
Article in English | ProQuest Central | ID: covidwho-1837965

ABSTRACT

Metal mesh devices (MMDs) are novel materials that enable the precise separation of particles by size. Structurally, MMDs consist of a periodic arrangement of square apertures of characteristic shapes and sizes on a thin nickel membrane. The present study describes the separation of aerosol particles using palm-top-size collection devices equipped with three types of MMDs differing in pore size. Aerosols were collected at a farm located in the suburbs of Nairobi, Kenya;aerosol particles were isolated, and pathogenic bacteria were identified in this microflora by next-generation sequencing analysis. The composition of the microflora in aerosol particles was found to depend on particle size. Gene fragments were obtained from the collected aerosols by PCR using primers specific for the genus Mycobacterium. This analysis showed that Mycobacterium obuense, a non-tuberculous species of mycobacteria that causes lung diseases, was present in these aerosols. These findings showed that application of this MMD analytical protocol to aerosol particles can facilitate the investigation of airborne pathogenic bacteria.

11.
J Mol Struct ; 1264: 133190, 2022 Sep 15.
Article in English | MEDLINE | ID: covidwho-1814975

ABSTRACT

This work explores the study of a synthesized nickel complex as a possible inhibitor against the main protease (Mpro) of the recent emerging coronavirus disease (COVID-19). Overall, the template reaction of 3-acetyl-2-hydroxy-6-methyl-4H-pyran-4-one with nickel(II) chloride hexahydrate in N,N-dimethylformamide (DMF) medium leads to the formation of neutral nickel complex. This resulting complex is formulated as [Ni(DHA)2(DMF)2] on the basis of FT-IR, UV-Vis., single-crystal X-ray diffraction analysis, magnetic susceptibility and CV measurements as well as DFT quantum chemical calculations. Its single crystal suggests was found to be surrounded by the both pairs of molecules of DHA and DMF through six oxygen atoms with octahedral coordination sphere. The obtained magnetic susceptibilities are positive and agree with its paramagnetic state. In addition to the experimental investigations, optimized geometry, spectroscopic and electronic properties were also performed using DFT calculation with B3LYP/6-31G(d,p) level of theory. The nonlinear optical (NLO) properties of this complex are again examined. Some suitable quantum descriptors (EHOMO, ELUMO, Energy gap, Global hardness), Milliken atomic charge, Electrophilic potion and Molecular Electrostatic Potential) have been elegantly described. Molecular docking results demonstrated that the docked nickel complex displayed remarkable binding energy with Mpro. Besides, important molecular properties and ADME pharmacokinetic profiles of possible Mpro inhibitors were assessed by in silico prediction.

12.
Energies ; 15(7):2564, 2022.
Article in English | ProQuest Central | ID: covidwho-1785587

ABSTRACT

In the roadmaps of the automotive industry, the electric vehicle (EV) is regarded as a crucial technology for the future of automotive power systems. The EV has become a top priority of major global car manufacturers and is expected to disrupt the road transportation sector. In Malaysia and Indonesia, EVs just started as an important force. However, in Malaysia, the lack of EV infrastructure, along with its strong dependency on fossil fuels, poses an enormous challenge. The situation is very similar in Indonesia. Indonesia has huge potential as Southeast Asia’s largest vehicle market and a major nickel producer, an important EV battery ingredient. Therefore, this article addresses several critical issues in implementing EVs in Malaysia and Indonesia. In preparing this review, we have thoroughly selected very important EV keywords that are frequently asked. We have also interviewed some prominent figures in the field of EV to address the most critical aspects worth including in the paper. In doing so, we plan to provide content that will be beneficial not only to the academic world but also to the automotive industry in general. Firstly, a summary of the EV adoption scenario in each country was presented. Afterwards, the types of EVs and battery capacities available in both countries were explained. The next section focused on the adoption rate of EVs, followed by the discussion of EVs charging infrastructure. In addition to that, issues pertaining to vehicle tax credit were also addressed. The opportunities and challenges of EV were then addressed in depth before concluding remarks were given.

13.
Coatings ; 12(3):302, 2022.
Article in English | ProQuest Central | ID: covidwho-1760420

ABSTRACT

The flexible and wearable capacitive sensors have captured tremendous interest due to their enormous potential for healthcare monitoring, soft robotics, and human−computer interface. However, despite recent progress, there are still pressing challenges to develop a fully integrated textile sensor array with good comfort, high sensitivity, multisensing capabilities, and ultra-light detection. Here, we demonstrate a pressure and non-contact bimodal fabric-only capacitive sensor with highly sensitive and ultralight detection. The graphene nanoplatelets-decorated multidimensional honeycomb fabric and nickel-plated woven fabric serve as the dielectric layer and electrode, respectively. Our textile-only capacitive bimodal sensor exhibits an excellent pressure-sensing sensitivity of 0.38 kPa−1, an ultralow detection limit (1.23 Pa), and cycling stability. Moreover, the sensor exhibits superior non-contact detection performance with a detection distance of 15 cm and a maximum relative capacitance change of 10%. The sensor can successfully detect human motion, such as finger bending, saliva swallowing, etc. Furthermore, a 4 × 4 (16 units) textile-only capacitive bimodal sensor array was prepared and has excellent spatial resolution and response performance, showing great potential for the wearable applications.

14.
IOP Conference Series. Earth and Environmental Science ; 988(3):032038, 2022.
Article in English | ProQuest Central | ID: covidwho-1730615

ABSTRACT

In practice, the industry and the business sector have felt the impact of the coronavirus that has spread around the world. Today it is not known when the system will recover, but it is already quite clear that the post-covid reality will require radically new approaches to the organization of mining operations. Usually, the conservative mining industry in Russia has felt the influence of new trends set by the pandemic, such as, for example, the transition of employees to remote work, which has spurred an accelerated transition to automated work;a change in the distribution chain, are inseparable from the closure of borders, the acquisition of new skills from staff, and others. This article focuses on the development of mining assets in the mining industry. The article concretizes the essence of geometry. Appropriate solutions for end-to-end optimization of the “mine-factory” system are outlined due to a deep understanding of the characteristics of the ore and the introduction of digital tools. The most popular innovations necessary for implementation into the modern mining process have been identified, ranked according to the categories “Production materials, technologies and equipment”, “Automation and digitalization”, “Field development”, “Technologies of deep processing of raw materials: green chemistry”, “Technologies of deep processing “processing of raw materials: green metallurgy”. The production assets of the Polar Division are analyzed using the example of PJSC Mining and Metallurgical Company Norilsk Nickel. As a project initiative to improve the efficiency of ore mining within the mine field, the reconstruction of a skip ventilation shaft from a cage to a skip-cage is being created. A variant of solving the geomechanical problems of the company is being considered.

15.
Reviews in Inorganic Chemistry ; 0(0):21, 2022.
Article in English | Web of Science | ID: covidwho-1677605

ABSTRACT

The rapid growth and revolution in the area of emerging therapeutics has been able to save the life of millions of patients globally. Besides these developments, the microbes are consistently struggling for their own survival and hence becoming quite more sturdy and incurable to existing drugs. Covid-19 virus and Black Fungus are recent examples of failure of medical preparations and strength of these viruses beyond the imagination of medical practitioners. Henceforth the study has made an extensive survey of exiting literature on heterocyclic schiff bases and their transition metal complexes to look for their potential applicability as antimicrobial agents. The inherent physiognomies of the essential properties of these transition metal complexes including thermodynamic, kinetic and chelating are comparatively modifiable as per requirements. The study has found that the biological applications of these transition metal complexes are well suited to be used as antibacterial and antifungal agents.

16.
6th International Conference of Computational Methods in Engineering Science, CMES 2021 ; 2130, 2021.
Article in English | Scopus | ID: covidwho-1672069

ABSTRACT

The crisis related to the COVID 19 pandemic caused an increase in nickel prices on the global markets. From this perspective, it seems promising to search for the possibilities of effective recycling of nickel-based alloys as biomaterials. The topic of the recasting of Ni-Cr dental alloys is currently being broadly described in the literature. Nonetheless, there are still no conclusive results on the impact of recasting on the quality of the cast dentures. Considering the aforementioned, for research, the effect of recasting on the wear resistance and microstructure of NiCrMo dental alloy was investigated. The Heraenium NA alloy was used for testing. Abrasion resistance was tested by the ball on disc method. Microstructure and wear trace were observed using an optical microscope and a scanning electron microscope. The tests showed a higher wear resistance of the re-casted material. The average coefficient of friction for the initially cast alloys was 0.664, while for the remelted samples the mean value was 0.441. The tested samples are characterised by an abrasive-adhesive wear mechanism. Piling up of the wear tracks edges was observed - the highest for H100. For the H100 samples, a slightly lower average hardness value (HV10) was observed - 226 compared to 233 (HV10) for the samples made from the re-casted alloy (H0). The presence of a dendritic structure of alloys was demonstrated. Blocky eutectic precipitations are visible against the matrix. The observed growth of interdendritic precipitations constitute a natural barrier for the counterpart material and increases its tribological properties. Obtained results suggest that alloy recasting does not constitute a limitation to its use. © 2021 Institute of Physics Publishing. All rights reserved.

17.
Energies ; 14(24):8590, 2021.
Article in English | ProQuest Central | ID: covidwho-1599625

ABSTRACT

[...]of the pandemic in 2020, prices for such raw materials as nickel, copper and coal showed a double-digit decline. The innovative development of mining technologies is also driven by the need for saturation the long-term demand for raw materials, the growth of which is attributed by experts to the “new industrialization” in BRICS countries, North Africa, South America, as well as to the large-scale digitalization and development of electric transport [3]. [...]the two aforementioned trends in the development of the global mining sector can be described as converging, due to the stimulating effect of climatic and pandemic factors on the long-term demand for raw materials. [...]we can talk about a consensus of views regarding the long-term prospects for demand for minerals, both in developed and developing countries, which is a positive factor in the development of technological modernization of the mining industry. [...]today, the role of people in the extraction of minerals is limited to the operating and maintenance of equipment with a highly specific capacity, which, on the one hand, can harm employees, and on the other, cause economic losses in the case of breakdowns due to the fault of personnel. [...]the development of technologies for ensuring labor safety at mining enterprises is closely related both to innovations in mining engineering and geotechnology and in the organization of mining operations.

18.
Blood ; 138:3215, 2021.
Article in English | EMBASE | ID: covidwho-1582287

ABSTRACT

Background Hospitalised patients with severe COVID-19 (requiring critical care level support) appear to be at increased risk of thrombosis despite standard pharmacological thromboprophylaxis. The magnitude of thrombotic risk in patients with COVID-19 of moderate severity (not requiring critical care) is less clear. The optimal approach to thromboprophylaxis (and the role of intensified thromboprophylaxis) remains to be determined. Evidence of endothelial dysfunction has been widely reported in COVID-19 (particularly in severe COVID) and this may contribute to hypercoagulability. Aim To assess differences in patterns of hypercoagulability and endothelial dysfunction between a group of patients with moderate COVID-19 and a group of age-matched hospitalized patients (SARS-CoV-2 PCR negative) receiving low molecular weight heparin (LMWH) thromboprophylaxis. Methods Blood was collected from individuals admitted to hospital with COVID-19 of moderate severity (not requiring critical care level support) and a group of age-matched patients admitted with infective/inflammatory illness (SARS-CoV-2 PCR negative). All subjects received standard-dose LMWH thromboprophylaxis, with blood drawn at 12 hours post-dose (and with measurement of anti-FXa activity levels). Circulating levels of endothelial & fibrinolytic markers including ICAM, PAI-1, VCAM, soluble thrombomodulin (sTM), and tissue plasminogen activator (tPA) were determined by ELISA. Thrombin generation (TG) in platelet-poor plasma was assessed by calibrated automated thrombography in the presence of tissue factor (Final concentration, 1pM & 5pM), thrombomodulin (TM) (Final concentration, 6.25nM), and an inhibitory anti-tissue factor pathway inhibitor antibody (anti-TFPI;Final concentration 100μg/mL). Results 14 COVID-19 positive subjects and 11 hospitalized controls were recruited. There were no differences in mean age (69.7±4.5 vs 61.6±4.7 years;p= 0.2) or mean Body mass index (25.7±1.1 vs 22.7±1.2 Kg/m2;p=0.1) between groups. No COVID-19 patient or control required critical care support. In the COVID group, radiological evidence of pneumonitis [diffuse (n=3) or peripheral infiltrates (n=7)] was present in the majority of cases. None of the COVID-19 cases were requiring supplemental oxygen at the time of recruitment. All controls were admitted with either respiratory or urinary infection [radiological evidence of pneumonia in 4/11;supplemental oxygen requirement in 2/11, (28-36% FiO2 via nasal cannula)]. Plasma levels of sTM, ICAM, PAI-1 & VCAM were similar in both groups. Levels of t-PA were significantly higher in the COVID group (8.31±4.35 vs 4.91±2.37 ng/mL;p= 0.005). Despite similar plasma anti-Xa activity in both groups (0.06 vs 0.04 IU/mL;p=0.2), mean endogenous thrombin potential (ETP) was significantly higher in the COVID group (1929±119.7 vs 1528±138.9 nM*min;p=0.02), although peak thrombin was similar (173.6±26 vs 161.5±31nM). ETP-TM ratio was similar between groups (0.3±0.1 vs 0.2±0.1;p=0.3). Despite increased ETP, the lag time to thrombin generation was significantly prolonged in the COVID group (8.3±0.6 vs 5.8±0.5 mins, p= 0.006). This pattern has previously been observed in vascular diseases associated with altered plasma tissue factor pathway inhibitor (TFPI) activity. In the presence of an anti-TFPI antibody, the difference in lagtime between groups was attenuated (4.7±0.2 vs 3.5±0.1 mins;p= 0.002) and the difference in overall thrombin generation (delta TG) between both groups became significantly increased (Fig.1). Conclusion Plasma thrombin generation is enhanced in patients with non-severe COVID-19 despite pharmacological thromboprophylaxis. Endothelial dysfunction is also observed in this group and appears to modulate parameters of plasma thrombin generation. The clinical implications of these observations are not known although clinical studies of intensified thromboprophylaxis in attenuating thrombotic risk and other complications are ongoing. Fig 1. Inhibition of TFPI activity enhances thrombin generation in COVID-19. n the presence of an inhibitory anti-TFPI antibody, peak plasma thrombin generation was enhanced in COVID-19 in contrast to that observed among SARS-CoV-2 PCR negative hospitalised patients (339.6+25.2 vs 247.4+10.1, p=0.01). [Formula presented] Disclosures: Maguire: Actelion: Research Funding;Bayer Pharma: Research Funding. Ni Ainle: Daiichi-Sankyo: Research Funding;Actelion: Research Funding;Leo Pharma: Research Funding;Bayer Pharma: Research Funding. Kevane: Leo Pharma: Research Funding.

19.
Allergy: European Journal of Allergy and Clinical Immunology ; 76(SUPPL 110):650, 2021.
Article in English | EMBASE | ID: covidwho-1570430

ABSTRACT

Background: The purpose of the study is to analyze the type of hypersensitivity reactions (HR) with Pfizer-BioNTech COVID-19 Vaccine (Comirnaty®) referred to our Allergy Department (AD), in order to asses vaccination with second dose safely. Method: Subjects with suspicion of HR after administration of first dose of Comirnaty® were referred to our AD from the Prevention and Occupational Risk Department responsible for the vaccination of hospital staff. Clinical history with special attention to atopic comorbidities and a detailed description of the HR after first dose of Comirnaty® was recorded. After providing signed informed consent, subjects underwent an allergy workup consisting of skin prick tests and intradermal tests (immediate and delayed readings) with polyethylene glycol (PEG) 4000 (1, 10 and 100 mg/ml), Polysorbate 80 (0.004 and 0.04 mg/dl), and Comirnaty® vaccine (as is). If skin tests proved negative, the second dose of Comirnaty® was administered under close supervision at our AD with an observation period of 60 minutes. Results: As of March 10, 2021, 6907 subjects had received the first dose of Comirnaty® and 5 were referred to our AD for evaluation. Mean age was 35 years, 4 were female and 1 male. Four patients had previous allergic history consisting of seasonal allergic rhinitis, contact dermatitis to nickel and thimerosal, and allergy to metamizole and mesalazine. After vaccination, two subjects had non-immediate reactions (NIR) that were generalized erythema within the first 48-96 h. Two subjects had immediate reactions (IR) 15 min after vaccination, consisting of generalized urticaria and erythema, and one was referred with a suspicion of immediate anaphylaxis but the reaction did not meet Brighton Anaphylaxis criteria. All subjects had negative skin tests with PEG-4000, Polysorbate 80 and Comirnaty®. The patient with the “suspicion of anaphylaxis” refused to receive the second dose. The remaining 4 subjects received the second dose of Comirnaty® with no reaction. Conclusion: The incidence of suggestive hypersensitivity reactions to Comirnaty® vaccine in our hospital staff was very low (0.07%). The administration of the second dose after a negative allergy workup seems safe, although the number of subjects treated is small.

20.
Allergy: European Journal of Allergy and Clinical Immunology ; 76(SUPPL 110):232, 2021.
Article in English | EMBASE | ID: covidwho-1570362

ABSTRACT

Case Report Background : Fixed drug eruption (FDE) is a rare delayed hypersensitivity reaction which is often misdiagnosed. Colchicine is a drug used for gout prophylaxis known to regulate multiple inflammatory pathways. Since 1996 only one case of colchicine-associated FDE has been reported. Case-presentation : A 58-year old man presented at the clinic with recurrent erythematous lesions on the right arm, hand, thighs, chest, and genitals which followed residual hyperpigmentation. First clinical presentation was in 2018 and upon subsequent episodes the lesions appeared on the same skin sites following a tendency to engage larger skin surface and new spots occurred. The patient reported on-demand treatment with colchicine, metamizole, paracetamol, diclofenac for gout arthritis, and acetylsalicylic acid/vitamine C, for Covid-19 prophylaxis. Epicutaneous patch tests with European standard series was performed on healthy skin, and patch testing with colchicine, paracetamol, diclofenac and metamizole was performed on lesional skin. Results were interpreted as positive for: nickel (++), peruvian balm (++), propolis (++), and colchicine (+). The patient did not report intake of food and drugs containing nickel, nor any consumption of honey and propolis-containing products. The patient's history, clinical presentation, and the positive colchicine patch test helped establish the diagnosis of colchicine-induced FDE. Conclusion : We report the second case of colchicine-induced FDE diagnosed for the first time by epicutaneous patch testing on lesional skin. Proper diagnosis might help evade further complications, and the need for oral challenge tests which could be associated with detrimental effects.

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