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1.
Histochem Cell Biol ; 158(4): 383-388, 2022 Oct.
Article in English | MEDLINE | ID: covidwho-2048270

ABSTRACT

Eosin Y is a common stain in histology. Although usually used for colourimetric imaging where the dye is used to stain pink/red a range of structures in the tissue, Eosin Y is also a fluorochrome, and has been used in this manner for decades. In this study our aim was to investigate the fluorescence properties of the dye to enable quantification of structures within formalin-fixed paraffin-embedded (FFPE) tissue sections. To do this, FFPE sections of hamster tissue were prepared with haematoxylin and eosin Y dyes. Spectral detection on a confocal laser scanning microscope was used to obtain the fluorescence emission spectra of the eosin Y under blue light. This showed clear spectral differences between the red blood cells and congealed blood, compared to the rest of the section. The spectra were so distinct that it was possible to discern these in fluorescence and multi-photon microscopy. An image analysis algorithm was used to quantify the red blood cells. These analyses could have broad applications in histopathology where differentiation is required, such as the analysis of clotting disorders to haemorrhage or damage from infectious disease.


Subject(s)
Fluorescent Dyes , Formaldehyde , Eosine Yellowish-(YS) , Lung , Microscopy, Confocal , Paraffin Embedding/methods , Tissue Fixation
2.
Sci Rep ; 12(1): 16038, 2022 09 26.
Article in English | MEDLINE | ID: covidwho-2050535

ABSTRACT

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causative agent of the COVID-19, which is a global pandemic, has infected more than 552 million people, and killed more than 6.3 million people. SARS-CoV-2 can be transmitted through airborne route in addition to direct contact and droplet modes, the development of disinfectants that can be applied in working spaces without evacuating people is urgently needed. TiO2 is well known with some features of the purification, antibacterial/sterilization, making it could be developed disinfectants that can be applied in working spaces without evacuating people. Facing the severe epidemic, we expect to fully expand the application of our proposed effective approach of mechanical coating technique (MCT), which can be prepared on a large-scale fabrication of an easy-to-use TiO2/Ti photocatalyst coating, with hope to curb the epidemic. The photocatalytic inactivation of SARS-CoV-2 and influenza virus, and the photocatalytic degradation of acetaldehyde (C2H4O) and formaldehyde (CH2O) has been investigated. XRD and SEM results show that anatase TiO2 successfully coats on the surface of Ti coatings, while the crystal structure of anatase TiO2 can be increased during the following oxidation in air. The catalytic activity towards methylene blue of TiO2/Ti coating balls has been significantly enhanced by the followed oxidation in air, showing a very satisfying photocatalytic degradation of C2H4O and CH2O. Notably, the TiO2/Ti photocatalyst coating balls demonstrate a significant antiviral activity, with a decrease rate of virus reached 99.96% for influenza virus and 99.99% for SARS-CoV-2.


Subject(s)
COVID-19 , Disinfectants , Acetaldehyde , Anti-Bacterial Agents , Antiviral Agents , Catalysis , Formaldehyde/chemistry , Humans , Methylene Blue/chemistry , SARS-CoV-2 , Titanium/chemistry , Titanium/pharmacology
3.
Viruses ; 14(9)2022 08 31.
Article in English | MEDLINE | ID: covidwho-2006233

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused huge social and economic distress. Given its rapid spread and the lack of specific treatment options, SARS-CoV-2 needs to be inactivated according to strict biosafety measures during laboratory diagnostics and vaccine development. The inactivation method for SARS-CoV-2 affects research related to the natural virus and its immune activity as an antigen in vaccines. In this study, we used size exclusion chromatography, western blotting, ELISA, an electron microscope, dynamic light scattering, circular dichroism, and surface plasmon resonance to evaluate the effects of four different chemical inactivation methods on the physical and biochemical characterization of SARS-CoV-2. Formaldehyde and ß-propiolactone (BPL) treatment can completely inactivate the virus and have no significant effects on the morphology of the virus. None of the four tested inactivation methods affected the secondary structure of the virus, including the α-helix, antiparallel ß-sheet, parallel ß-sheet, ß-turn, and random coil. However, formaldehyde and long-term BPL treatment (48 h) resulted in decreased viral S protein content and increased viral particle aggregation, respectively. The BPL treatment for 24 h can completely inactivate SARS-CoV-2 with the maximum retention of the morphology, physical properties, and the biochemical properties of the potential antigens of the virus. In summary, we have established a characterization system for the comprehensive evaluation of virus inactivation technology, which has important guiding significance for the development of vaccines against SARS-CoV-2 variants and research on natural SARS-CoV-2.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines , Formaldehyde , Humans , Propiolactone/pharmacology , Vaccines, Inactivated
4.
Biologicals ; 79: 31-37, 2022 Sep.
Article in English | MEDLINE | ID: covidwho-2003881

ABSTRACT

The conventional PCR remains a valuable method to detect the newly emergent coronavirus rapidly and accurately. Our investigation aimed to establish the standard materials of SARS-CoV-2 for NAAT detection. We provided formalin-inactivated SARS-CoV-2 and confirmed RNA copy numbers. In addition, the virus genome was confirmed with whole-genome sequencing and identified as Wuhan/WI04/2019. Seven laboratories were invited for this collaborative study, according to the reporting data, we determined the SARS-CoV-2 with the unit of 6.35 Log10 copies/mL as the national standard. The availability of the national standard (NS) of SARS-CoV-2 will facilitate the standardization and harmonization of SARS-CoV-2 NAAT assays.


Subject(s)
COVID-19 , RNA, Viral , COVID-19/diagnosis , Formaldehyde , Humans , Polymerase Chain Reaction/methods , RNA, Viral/genetics , SARS-CoV-2/genetics , Taiwan
5.
Chemosphere ; 308(Pt 1): 136075, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-1996067

ABSTRACT

This study investigated the changes in air pollutant's concentration, spatio-temporal distribution and sensitivity of changes in air pollutant's concentration during pre and post COVID-19 outbreak. We employed Google Earth Engine Platform to access remote sensing datasets of air pollutants across Asian continent. Air pollution and cumulative confirmed-COVID cases data of Asian countries (Afghanistan, Bangladesh, China, India, Iran, Iraq, Pakistan, and Saudi Arabia) have been collected and analyzed for 2019 and 2020. The results indicate that aerosol index (AI) and nitrogen dioxide (NO2) is significantly reduced during COVID outbreak i.e. in year 2020. In addition, we found significantly positive (P < 0.05, 95% confidence interval, two-tailed) correlation between changes in AI and NO2 concentration for net active-COVID case increment in almost each country. For other atmospheric gases i.e. carbon monoxide (CO), formaldehyde (HCHO), ozone (O3), and Sulfur dioxide (SO2), insignificant and/or significant negative correlation is also observed. These results suggest that the atmospheric concentration of AI and NO2 are good indicators of human activities. Furthermore, the changes in O3 shows significantly negative correlation for net active-COVID case increment. In conclusion, we observed significant positive environmental impact of COVID-19 restrictions in Asia. This study would help and assist environmentalist and policy makers in restraining air pollution by implementing efficient restrictions on human activities with minimal economic loss.


Subject(s)
Air Pollutants , Air Pollution , COVID-19 , Environmental Pollutants , Ozone , Air Pollutants/analysis , Air Pollution/analysis , COVID-19/epidemiology , Carbon Monoxide/analysis , Environmental Monitoring/methods , Formaldehyde , Humans , Nitrogen Dioxide/analysis , Ozone/analysis , Pakistan , Pandemics , Particulate Matter/analysis , Sulfur Dioxide/analysis
6.
Clin Chim Acta ; 532: 181-187, 2022 Jul 01.
Article in English | MEDLINE | ID: covidwho-1966413

ABSTRACT

BACKGROUND: SARS-CoV-2 is an RNA virus that primarily causes respiratory disease; however, infection of other tissue has been reported. Evaluation of SARS-CoV-2 in tissue specimens may increase understanding of SARS-CoV-2 pathobiology. MATERIALS AND METHODS: A qualitative test for detection of SARS-CoV-2 in formalin-fixed paraffin-embedded (FFPE) tissues was developed and validated using droplet digital PCR (ddPCR), which has a lower limit of detection than reverse transcription (RT)-qPCR. After extraction of total RNA from unstained FFPE tissue, SARS-CoV-2 nucleocapsid (N1, N2) target sequences were amplified and quantified, along with human RPP30 as a control using the Bio-Rad SARS-CoV-2 ddPCR kit. RESULTS: SARS-CoV-2 was detected in all 21 known positive samples and none of the 16 negative samples. As few as approximately 5 viral copies were reliably detected. Since January 2021, many tissue types have been clinically tested. Of the 195 clinical specimens, the positivity rate was 35% with placenta and fetal tissue showing the highest percentage of positive cases. CONCLUSION: This sensitive FFPE-based assay has broad clinical utility with applications as diverse as pregnancy loss and evaluation of liver transplant rejection. This assay will aid in understanding atypical presentations of COVID-19 as well as long-term sequelae.


Subject(s)
COVID-19 , RNA, Viral , Real-Time Polymerase Chain Reaction , SARS-CoV-2 , COVID-19/diagnosis , Formaldehyde , Humans , Paraffin Embedding , RNA, Viral/isolation & purification , SARS-CoV-2/genetics
8.
J Environ Sci Health A Tox Hazard Subst Environ Eng ; 57(3): 193-197, 2022.
Article in English | MEDLINE | ID: covidwho-1730453

ABSTRACT

Since the Coronavirus Disease 2019 (COVID-19) pandemic began, people have been wearing face masks for many hours every day. As these face masks are in contact with the skin, it is important to pay more attention to their quality and safety. This study examined the concentration of free formaldehyde in 90 non-medical face masks and related products (33 nonwoven, 30 woven cloth, 12 polyurethane, and 15 related products) because formaldehyde is a common contact allergen in textile products. For products consisting of mixed materials, each material was sampled, resulting in 103 samples for analysis. Free formaldehyde (34-239 µg/g) was found in three cloth masks, which consisted of cotton and polyester, with antibacterial and antiviral labeling. It was confirmed that the detected formaldehyde originated from the mask-finishing treatment by a hydrochloric acid extraction discrimination test. These masks may elicit contact dermatitis if the consumers have already been sensitized to formaldehyde. However, the risk of contact dermatitis caused by formaldehyde in masks may be considered low since the frequency of formaldehyde detection in masks in Japan is low.


Subject(s)
COVID-19 , Dermatitis, Contact , COVID-19/epidemiology , COVID-19/prevention & control , Dermatitis, Contact/epidemiology , Formaldehyde/toxicity , Humans , Japan , Masks , Pandemics , SARS-CoV-2
9.
Acta Trop ; 226: 106220, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1719144

ABSTRACT

PURPOSE: Agar-plate culture (APC) remains the most sensitive parasitological technique for S. stercoralis diagnosis. Although it was first described three decades ago, the time of incubation of the plates is neither a commonly described feature nor usually standardized. The aim of the study was to analyze the required time to detect S. stercoralis larvae in APC. METHODS: A prospective laboratory-based study including all patients with at least one positive APC was performed. The plates were incubated at room temperature for 7 days. Clinical, analytical and parasitological features including results of the direct visualization of the stool (DV) after formalin-ether concentration and time-to-detection (TTD) of the larvae in APC were recorded. RESULTS: A total of 141 samples from 75 patients had a positive APC. In 49 of them (65.3%) three or more stool samples were processed for direct visualization (DV) and APC. Of these 49 patients, 8 (16.3%) were also diagnosed with DV and 41 (83.7%) were diagnosed only with APC. In 38 samples from 23 (30.7%) patients, the TTD was below 2 days, while in 27 samples from 13 (17.3%) patients, the larvae were detected on the 6th and 7th day. CONCLUSION: Direct visualization failed to detect S. stercoralis in most of the patients that were diagnosed with APC. Incubation periods below 2 and 5 days would miss an important percentage of infections. At least 7 days of incubation of the APC are required to detect presumably low-burden chronic infections in non-endemic countries.


Subject(s)
Strongyloides stercoralis , Strongyloidiasis , Agar , Animals , Feces , Formaldehyde , Humans , Prospective Studies , Strongyloidiasis/diagnosis
10.
Eur J Ophthalmol ; 32(6): 3674-3678, 2022 Nov.
Article in English | MEDLINE | ID: covidwho-1714592

ABSTRACT

PURPOSE: To describe the clinical features, histopathological findings, and prognosis of conjunctival Teddy bear granuloma (TBG) diagnosed in a Mexican ophthalmologic referral center in a period of 64 years. METHODS: We reviewed clinical and histopathological material from all patients with documented conjunctival TBG. Patient's age, gender, location, clinical signs and symptoms, duration, treatment and, specimen size, were evaluated. Formalin-fixed paraffin embedded 5 microns hematoxylin-eosin stained slides and periodic acid-Schiff special stain as well as examination under polarized light microscopy were performed in all cases. RESULTS: A total of 5 conjunctival TBG were collected. The ages of the patients ranged between 2 and 11 with a mean of 6 years. Female to male ratio was 4:1. The right inferior fornix was involved in 4 cases (80%) with clinical diagnosis of conjunctival mass of unknown etiology. Treatment consisted of surgical removal by slit-lamp biomicroscopy (3 cases) and in the operating room (2 cases). No complications were informed in a short follow-up period. Histopathologically, numerous cross-sections of synthetic and non-synthetic fibers surrounded by multinucleated foreign body giant cells, epithelioid histiocytes, lymphocytes, plasma cells and sparse neutrophils were seen. Polarization light microscopy demonstrated numerous birefringent colorful foreign fibers. The follow-up period of the patients ranged between 1 and 32 weeks with a mean of 10 weeks. CONCLUSIONS: Most patients with TBG are children with vague, non-specific symptoms troubling precise clinical diagnosis. Treatment of choice involves surgical excision of the foreign body granuloma followed by topical corticosteroids. All surgical specimens obtained must be sent for histopathological examination. Special awareness is recommended during COVID-19 pandemic lockdown to prevent potential exposure to fibers that may cause conjunctival TBG.


Subject(s)
COVID-19 , Conjunctival Diseases , Conjunctivitis , Granuloma, Foreign-Body , Adrenal Cortex Hormones , Child , Child, Preschool , Cicatrix/complications , Communicable Disease Control , Conjunctival Diseases/diagnosis , Conjunctival Diseases/etiology , Conjunctival Diseases/surgery , Eosine Yellowish-(YS) , Female , Formaldehyde , Granuloma, Foreign-Body/diagnosis , Granuloma, Foreign-Body/etiology , Granuloma, Foreign-Body/surgery , Hematoxylin , Humans , Male , Pandemics , Periodic Acid
11.
STAR Protoc ; 3(1): 101156, 2022 03 18.
Article in English | MEDLINE | ID: covidwho-1671315

ABSTRACT

Here we present an optimized protocol for transcriptome profiling of COVID-19 patient samples, including peripheral blood mononuclear cells (PBMCs) and formalin-fixed paraffin-embedded tissue samples obtained from the lung, liver, heart, kidney, and spleen, with the matched controls. We describe RNA extraction and subsequent transcriptome analysis using NanoString technology of the patient samples. The protocol provides information about sample preparation, RNA extraction, and NanoString profiling and analysis. It can be also applied to differentiated Th17 and Treg subsets or formalin-fixed colon tissue samples. For complete details on the use and execution of this protocol, please refer to Wang et al. (2021).


Subject(s)
COVID-19/diagnosis , Formaldehyde/chemistry , Leukocytes, Mononuclear/metabolism , RNA, Viral/genetics , SARS-CoV-2/genetics , Tissue Fixation/methods , Transcriptome , Adult , Aged , Aged, 80 and over , Autopsy , COVID-19/genetics , COVID-19/virology , Case-Control Studies , Female , Humans , Male , Middle Aged , RNA, Viral/analysis , SARS-CoV-2/isolation & purification , Young Adult
12.
Allergy Asthma Proc ; 43(1): 20-29, 2022 01 01.
Article in English | MEDLINE | ID: covidwho-1603559

ABSTRACT

Background: Recent advances in vaccination against the severe acute respiratory syndrome coronavirus 2 pandemic have brought allergists and dermatologists to the forefront because both immediate and delayed hypersensitivity reactions have been reported. Objective: This literature review focused on delayed reactions to vaccines, including possible causative agents and practical information on how to diagnose, evaluate with patch testing, and manage subsequent dose administration. Methods: Currently published reviews and case reports in PubMed, along with data on vaccines from the Centers for Disease Control and Prevention web site. Relevant case reports and reviews that focused on delayed reactions to vaccines were selected. Results: Most delayed hypersensitivity reactions to vaccines include cutaneous manifestations, which vary from local persistent pruritic nodules to systemic rashes. The onset is usually within a few days but can be delayed by weeks. Multiple excipients have been identified that have been implicated in delayed vaccine reactions, including thimerosal, formaldehyde, aluminum, antibiotics, and gelatin. Treatment with antihistamines, topical corticosteroids, or systemic corticosteroids alleviates symptoms in most patients. Such reactions are generally not contraindications to future vaccination. However, for more-severe reactions, patch testing for causative agents can be used to aid in diagnosis and approach further vaccination. Conclusion: Delayed-type hypersensitivity reactions to vaccines are not uncommon. If needed, patch testing can be used to confirm agents, including antibiotics, formaldehyde, thimerosal, and aluminum. In most cases, delayed cutaneous reactions are not contraindications to further vaccine administration.


Subject(s)
Hypersensitivity, Delayed , Vaccines , Adrenal Cortex Hormones/therapeutic use , Aluminum/adverse effects , Anti-Bacterial Agents/adverse effects , COVID-19 , Excipients/adverse effects , Formaldehyde/adverse effects , Humans , Hypersensitivity, Delayed/chemically induced , Hypersensitivity, Delayed/diagnosis , Thimerosal/adverse effects , United States , Vaccines/adverse effects
13.
Indian J Ophthalmol ; 69(12): 3752-3755, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1538645

ABSTRACT

The foundation of an ophthalmologists' microsurgical career begins in the wet lab. Training on donor cadaveric, animal like goat or pig eyes provide the most realistic surgical environment, however, the availability of a donor's eyes for practice is limited. This scarcity is further escalated in this current coronavirus disease 2019 pandemic where eye donations have decreased. Even among those eyes which find their way into the wet lab, quite a few would have collapsed significantly making training difficult. Therefore, we looked at ways to salvage these collapsed globes. We describe a novel way of salvaging the collapsed eyeballs by injecting formalin in slow boluses into the vitreous cavity. The longer maintenance of the globe integrity without necessitating repeated injections facilitates better quality of surgical training and optimal utilization of these eyes.


Subject(s)
COVID-19 , Eye Diseases , Ophthalmology , Animals , Formaldehyde , Humans , SARS-CoV-2 , Swine
14.
ScientificWorldJournal ; 2021: 9342748, 2021.
Article in English | MEDLINE | ID: covidwho-1495720

ABSTRACT

BACKGROUND: Recently, an outbreak of a novel human coronavirus SARS-CoV-2 has become a world health concern leading to severe respiratory tract infections in humans. Virus transmission occurs through person-to-person contact, respiratory droplets, and contaminated hands or surfaces. Accordingly, we aim at reviewing the literature on all information available about the persistence of coronaviruses, including human and animal coronaviruses, on inanimate surfaces and inactivation strategies with biocides employed for chemical and physical disinfection. METHOD: A comprehensive search was systematically conducted in main databases from 1998 to 2020 to identify various viral disinfectants associated with HCoV and methods for control and prevention of this newly emerged virus. RESULTS: The analysis of 62 studies shows that human coronaviruses such as severe acute respiratory syndrome (SARS) coronavirus, Middle East respiratory syndrome (MERS) coronavirus or endemic human coronaviruses (HCoV), canine coronavirus (CCV), transmissible gastroenteritis virus (TGEV), and mouse hepatitis virus (MHV) can be efficiently inactivated by physical and chemical disinfectants at different concentrations (70, 80, 85, and 95%) of 2-propanol (70 and 80%) in less than or equal to 60 s and 0.5% hydrogen peroxide or 0.1% sodium hypochlorite within 1 minute. Additionally, glutaraldehyde (0.5-2%), formaldehyde (0.7-1%), and povidone-iodine (0.1-0.75%) could readily inactivate coronaviruses. Moreover, dry heat at 56°C, ultraviolet light dose of 0.2 to 140 J/cm2, and gamma irradiation could effectively inactivate coronavirus. The WHO recommends the use of 0.1% sodium hypochlorite solution or an ethanol-based disinfectant with an ethanol concentration between 62% and 71%. CONCLUSION: The results of the present study can help researchers, policymakers, health decision makers, and people perceive and take the correct measures to control and prevent further transmission of COVID-19. Prevention and decontamination will be the main ways to stop the ongoing outbreak of COVID-19.


Subject(s)
COVID-19/prevention & control , Disinfectants/pharmacology , Disinfection/instrumentation , SARS-CoV-2 , Virus Inactivation/drug effects , 2-Propanol/pharmacology , Animals , COVID-19/virology , Coronavirus, Canine/drug effects , Disinfection/methods , Ethanol/pharmacology , Formaldehyde/pharmacology , Gamma Rays , Glutaral/pharmacology , Hot Temperature , Humans , Hydrogen Peroxide/pharmacology , Mice , Middle East Respiratory Syndrome Coronavirus/drug effects , Murine hepatitis virus/drug effects , Povidone-Iodine/pharmacology , SARS Virus/drug effects , Sodium Hypochlorite/pharmacology , Transmissible gastroenteritis virus/drug effects , Ultraviolet Rays
15.
J Anat ; 239(5): 1221-1225, 2021 11.
Article in English | MEDLINE | ID: covidwho-1462840

ABSTRACT

Teaching and learning anatomy by using human cadaveric specimens has been a foundation of medical and biomedical teaching for hundreds of years. Therefore, the majority of institutions that teach topographical anatomy rely on body donation programmes to provide specimens for both undergraduate and postgraduate teaching of gross anatomy. The COVID-19 pandemic has posed an unprecedented challenge to anatomy teaching because of the suspension of donor acceptance at most institutions. This was largely due to concerns about the potential transmissibility of the SARS-CoV-2 virus and the absence of data about the ability of embalming solutions to neutralise the virus. Twenty embalming solutions commonly used in institutions in the United Kingdom and Ireland were tested for their ability to neutralise SARS-CoV-2, using an established cytotoxicity assay. All embalming solutions tested neutralised SARS-CoV-2, with the majority of solutions being effective at high-working dilutions. These results suggest that successful embalming with the tested solutions can neutralise the SARS-CoV-2 virus, thereby facilitating the safe resumption of body donation programmes and cadaveric anatomy teaching.


Subject(s)
COVID-19/virology , Disease Transmission, Infectious/prevention & control , Embalming/methods , Formaldehyde/pharmacology , Pandemics , SARS-CoV-2 , Tissue Fixation/methods , COVID-19/transmission , Cadaver , Cells, Cultured , Fixatives/pharmacology , Humans
16.
STAR Protoc ; 2(3): 100696, 2021 09 17.
Article in English | MEDLINE | ID: covidwho-1322393

ABSTRACT

Angiotensin-converting enzyme 2 (ACE2) is a key cellular entry factor for severe acute respiratory syndrome coronavirus 2. Hence, identifying cell types that express ACE2 is important for understanding the pathophysiology of coronavirus disease 2019. We performed extensive testing of multiple primary antibodies across various human tissue types. Here, we describe an optimized protocol for immunostaining of ACE2 in formalin-fixed paraffin-embedded human pancreas, small intestine, and kidney tissue sections obtained from organ donors and autopsies. For complete details on the use and execution of this protocol, please refer to Kusmartseva et al. (2020).


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , COVID-19/diagnosis , Formaldehyde/chemistry , Immunohistochemistry/methods , Paraffin Embedding/methods , SARS-CoV-2/isolation & purification , Tissue Fixation/methods , COVID-19/metabolism , COVID-19/virology , Humans
17.
J Mol Diagn ; 23(9): 1065-1077, 2021 09.
Article in English | MEDLINE | ID: covidwho-1318904

ABSTRACT

Implementation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing in the daily practice of pathology laboratories requires procedure adaptation to formalin-fixed, paraffin-embedded (FFPE) samples. So far, one study reported the feasibility of SARS-CoV-2 genome sequencing on FFPE tissues with only one contributory case of two. This study optimized SARS-CoV-2 genome sequencing using the Ion AmpliSeq SARS-CoV-2 Panel on 22 FFPE lung tissues from 16 deceased coronavirus disease 2019 (COVID-19) patients. SARS-CoV-2 was detected in all FFPE blocks using a real-time RT-qPCR targeting the E gene with crossing point (Cp) values ranging from 16.02 to 34.16. Sequencing was considered as contributory (i.e. with a uniformity >55%) for 17 FFPE blocks. Adapting the number of target amplification PCR cycles according to the RT-qPCR Cp values allowed optimization of the sequencing quality for the contributory blocks (i.e. 20 PCR cycles for blocks with a Cp value <28 and 25 PCR cycles for blocks with a Cp value between 28 and 30). Most blocks with a Cp value >30 were non-contributory. Comparison of matched frozen and FFPE tissues revealed discordance for only three FFPE blocks, all with a Cp value >28. Variant identification and clade classification was possible for 13 patients. This study validates SARS-CoV-2 genome sequencing on FFPE blocks and opens the possibility to explore correlation between virus genotype and histopathologic lesions.


Subject(s)
COVID-19/virology , Genome, Viral/genetics , Lung/virology , Real-Time Polymerase Chain Reaction/methods , SARS-CoV-2/genetics , Autopsy , COVID-19/pathology , Formaldehyde , High-Throughput Nucleotide Sequencing/methods , Humans , Lung/pathology , Paraffin Embedding , SARS-CoV-2/isolation & purification , Tissue Fixation/methods
18.
Am J Clin Pathol ; 155(6): 802-814, 2021 05 18.
Article in English | MEDLINE | ID: covidwho-1272956

ABSTRACT

OBJECTIVES: The novel coronavirus, severe acute respiratory syndrome coronavirus 2, causing coronavirus disease 2019 (COVID-19) remains a global health threat and a significant source of human morbidity and mortality. While the virus primarily induces lung injury, it also has been reported to cause hepatic sequelae. METHODS: We aimed to detect the virus in formalin-fixed tissue blocks and document the liver injury patterns in patients with COVID-19 compared with a control group. RESULTS: We were able to detect viral RNA in the bronchioalveolar cell blocks (12/12, 100%) and formalin-fixed, paraffin-embedded tissue of the lung (8/8, 100%) and liver (4/9, 44%) of patients with COVID-19. Although the peak values of the main liver enzymes and bilirubin were higher in the patients with COVID-19 compared with the control group, the differences were not significant. The main histologic findings were minimal to focal mild portal tract chronic inflammation (7/8, 88%, P < .05) and mild focal lobular activity (6/8, 75%, P = .06). CONCLUSIONS: We found that most patients who died of COVID-19 had evidence of mild focal hepatitis clinically and histologically; however, the virus was detected in less than half of the cases.


Subject(s)
COVID-19/virology , Formaldehyde , Liver/pathology , SARS-CoV-2/pathogenicity , Tissue Fixation , Adult , Aged , Aged, 80 and over , Female , Humans , Inflammation/pathology , Liver/virology , Lung/pathology , Lung/virology , Male , Middle Aged , RNA, Viral/genetics , Tissue Fixation/methods
19.
Int J Environ Res Public Health ; 18(12)2021 06 11.
Article in English | MEDLINE | ID: covidwho-1270040

ABSTRACT

Knowledge, beliefs, and practices regarding infectious diseases are key elements that ensure practitioners' health and safety. It is important to carry out such a survey in hotels. This study aims to determine the levels of knowledge, beliefs, and practices regarding infectious diseases among practitioners and their associations with the environmental quality of hotels in Wuhan, China. We surveyed infectious disease knowledge, beliefs, and practices of practitioners in 18 hotels and detected these hotels' environment, including physical factors of temperature, humidity, noise, and the indoor air quality of benzene, toluene, xylene, formaldehyde, CO, CO2, the total count of fungi, aerobic plate count, PM10, and PM2.5. 128 practitioners were included, and 28.9% were male. The questionnaire included knowledge, beliefs, and practices regarding infectious diseases. Our study found moderate levels of knowledge and beliefs, and good health practices. People's beliefs toward COVID-19 were correlated significantly with their knowledge (p < 0.05). Beliefs and health practices were correlated significantly with environmental quality (p < 0.05). However, the environmental quality was correlated negatively with the classification of hotels. Conclusively, despite the good health practices of practitioners, the knowledge and beliefs toward infectious diseases need to strengthen. Hotels should emphasize health education in practitioners and the improvement of environmental hygiene. Integrating all three components into a comprehensive environmental promotion program is warranted.


Subject(s)
Air Pollution, Indoor , COVID-19 , Communicable Diseases , Air Pollution, Indoor/analysis , China , Formaldehyde , Humans , Male , SARS-CoV-2
20.
Bioessays ; 43(6): e2000312, 2021 06.
Article in English | MEDLINE | ID: covidwho-1184571

ABSTRACT

Biocidal agents such as formaldehyde and glutaraldehyde are able to inactivate several coronaviruses including SARS-CoV-2. In this article, an insight into one mechanism for the inactivation of these viruses by those two agents is presented, based on analysis of previous observations during electron microscopic examination of several members of the orthocoronavirinae subfamily, including the new virus SARS-CoV-2. This inactivation is proposed to occur through Schiff base reaction-induced conformational changes in the spike glycoprotein leading to its disruption or breakage, which can prevent binding of the virus to cellular receptors. Also, a new prophylactic and therapeutic measure against SARS-CoV-2 using acetoacetate is proposed, suggesting that it could similarly break the viral spike through Schiff base reaction with lysines of the spike protein. This measure needs to be confirmed experimentally before consideration. In addition, a new line of research is proposed to help find a broad-spectrum antivirus against several members of this subfamily.


Subject(s)
Disinfectants/pharmacology , Ketone Bodies/pharmacology , SARS-CoV-2/drug effects , Spike Glycoprotein, Coronavirus/metabolism , Animals , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Disinfectants/chemistry , Formaldehyde/chemistry , Formaldehyde/pharmacology , Glutaral/chemistry , Glutaral/pharmacology , Humans , Ketone Bodies/chemistry , Ketone Bodies/metabolism , Ketosis/etiology , Ketosis/virology , SARS-CoV-2/pathogenicity , Virion/drug effects , Virion/pathogenicity
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