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1.
Curr Hepatol Rep ; 21(2): 9-20, 2022.
Article in English | MEDLINE | ID: covidwho-1889028

ABSTRACT

Background and Purpose of Review: The COVID-19 pandemic has resulted in over 800,000 deaths worldwide and resulted in fundamental changes in practice in nearly every aspect of medicine. The majority of symptomatic patients experience liver-associated enzyme (LAE) elevations which appear to be correlated to disease severity. Furthermore, there are unique considerations of COVID-19 on chronic liver disease. Background, including epidemiology, pathophysiologic mechanisms and therapeutics, as well as the impact of COVID-19 on specific chronic liver disease, is discussed. Findings: Studies suggest that degree of LAE elevation correlates with illness severity, although it is unclear whether this represents true liver injury. Numerous proposed treatments for COVID-19 have been linked with drug induced liver injury and may have clinically significant drug-drug interactions. Others may have unintended consequences on chronic liver disease treatment including reactivation of hepatitis B. The risk of severe COVID-19 in patients with chronic liver disease is largely unknown; metabolic dysfunction-associated fatty liver disease may be linked to higher risk for severe illness. Implications for cirrhosis of other etiologies, autoimmune hepatitis, and viral hepatitis are less well defined. The treatment of chronic liver disease has been severely impacted by the pandemic. The societal factors created by the pandemic have led to decreased in person visits, evolving access to invasive screening modalities, food and financial insecurity, and likely increased alcohol use. Conclusions: The impacts of COVID-19 on the liver range from a potential increased risk of severe infection in chronic liver disease patients, to hepatotoxic effects of proposed treatments, to second and third order impacts on the care of patients with chronic liver disease.

2.
J Med Virol ; 94(8): 3722-3730, 2022 Aug.
Article in English | MEDLINE | ID: covidwho-1888725

ABSTRACT

To mitigate SARS-CoV-2 transmission, vaccines have been urgently approved. With their limited availability, it is critical to distribute the vaccines reasonably. We simulated the SARS-CoV-2 transmission for 365 days over four intervention periods: free transmission, structural mitigation, personal mitigation, and vaccination. Sensitivity analyses were performed to obtain robust results. We further evaluated two proposed vaccination allocations, including one-dose-high-coverage and two-doses-low-coverage, when the supply was low. 33.35% (infection rate, 2.68 in 10 million people) and 40.54% (2.36) of confirmed cases could be avoided as the nonpharmaceutical interventions (NPIs) adherence rate rose from 50% to 70%. As the vaccination coverage reached 60% and 80%, the total infections could be reduced by 32.72% and 41.19%, compared to the number without vaccination. When the durations of immunity were 90 and 120 days, the infection rates were 2.67 and 2.38. As the asymptomatic infection rate rose from 30% to 50%, the infection rate increased 0.92 (SD, 0.16) times. Conditioned on 70% adherence rate, with the same amount of limited available vaccines, the 20% and 40% vaccination coverage of one-dose-high-coverage, the infection rates were 2.70 and 2.35; corresponding to the two-doses-low-coverage with 10% and 20% vaccination coverage, the infection rates were 3.22 and 2.92. Our results indicated as the duration of immunity prolonged, the second wave of SARS-CoV-2 would be delayed and the scale would be declined. On average, the total infections in two-doses-low-coverage was 1.48 times (SD, 0.24) as high as that in one-dose-high-coverage. It is crucial to encourage people in order to improve vaccination coverage and establish immune barriers. Particularly when the supply is limited, a wiser strategy to prevent SARS-CoV-2 is equally distributing doses to the same number of individuals. Besides vaccination, NPIs are equally critical to the prevention of widespread of SARS-CoV-2.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/prevention & control , Humans , Models, Theoretical , Vaccination
3.
Vaccines (Basel) ; 10(6)2022 Jun 09.
Article in English | MEDLINE | ID: covidwho-1884443

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a virus that belongs to the coronavirus family and is the cause of coronavirus disease 2019 (COVID-19). As of May 2022, it had caused more than 500 million infections and more than 6 million deaths worldwide. Several vaccines have been produced and tested over the last two years. The SARS-CoV-2 virus, on the other hand, has mutated over time, resulting in genetic variation in the population of circulating variants during the COVID-19 pandemic. It has also shown immune-evading characteristics, suggesting that vaccinations against these variants could be potentially ineffective. The purpose of this review article is to investigate the key variants of concern (VOCs) and mutations of the virus driving the current pandemic, as well as to explore the transmission rates of SARS-CoV-2 VOCs in relation to epidemiological factors and to compare the virus's transmission rate to that of prior coronaviruses. We examined and provided key information on SARS-CoV-2 VOCs in this study, including their transmissibility, infectivity rate, disease severity, affinity for angiotensin-converting enzyme 2 (ACE2) receptors, viral load, reproduction number, vaccination effectiveness, and vaccine breakthrough.

4.
Interdiscip Neurosurg ; 29: 101599, 2022 Sep.
Article in English | MEDLINE | ID: covidwho-1882106

ABSTRACT

Background: Initially, novel severe acute respiratory syndrome coronavirus (SARS-CoV-2) was considered primarily a respiratory pathogen. However, with time it has behaved as a virus with the potential to cause multi-system involvement, including neurological manifestations which varies from acute to subacute onset of headache, seizures, a decrease of consciousness, and paralysis. Case description: Two cases of cerebral sinus venous thrombosis in COVID-19 patients were reported, following respiratory disorders, which was triggered by the SARS-CoV-2 infection. The first patient, presented with a decrease in level of consciousness and hemiparesis, was 23 years old female having no history of previous medical co-morbidities. The latter case, 21 years old woman showed less severe presentations of COVID-19 associated with headache, vomiting and papilledema. These two cases marvellously improved with no neurological deficit with aggressive course of anticoagulation. Conclusion: CVST should be suspected in COVID-19 patients presenting with headache, paralysis, aphasia or seizures. The high mortality rate of CVST in COVID-19 infection warrants a high index of suspicion from physicians, and early treatment with anticoagulation should be initiated.

5.
Microbiol Spectr ; 10(3): e0071622, 2022 Jun 29.
Article in English | MEDLINE | ID: covidwho-1879117

ABSTRACT

The evolutional process of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) development remains inconclusive. This study compared the genome sequences of severe acute respiratory syndrome coronavirus (SARS-CoV), bat coronavirus RaTG13, and SARS-CoV-2. In total, the genomes of SARS-CoV-2 and RaTG13 were 77.9% and 77.7% identical to the genome of SARS-CoV, respectively. A total of 3.6% (1,068 bases) of the SARS-CoV-2 genome was derived from insertion and/or deletion (indel) mutations, and 18.6% (5,548 bases) was from point mutations from the genome of SARS-CoV. At least 35 indel sites were confirmed in the genome of SARS-CoV-2, in which 17 were with ≥10 consecutive bases long. Ten of these relatively long indels were located in the spike (S) gene, five in nonstructural protein 3 (Nsp3) gene of open reading frame (ORF) 1a, and one in ORF8 and noncoding region. Seventeen (48.6%) of the 35 indels were based on insertion-and-deletion mutations with exchanged gene sequences of 7-325 consecutive bases. Almost the complete ORF8 gene was replaced by a single 325 consecutive base-long indel. The distribution of these indels was roughly in accordance with the distribution of the rate of point mutation rate around the indels. The genome sequence of SARS-CoV-2 was 96.0% identical to that of RaTG13. There was no long insertion-and-deletion mutation between the genomes of RaTG13 and SARS-CoV-2. The findings of the uneven distribution of multiple indels and the presence of multiple long insertion-and-deletion mutations with exchanged consecutive base sequences in the viral genome may provide insights into SARS-CoV-2 development. IMPORTANCE The developmental mechanism of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains inconclusive. This study compared the base sequence one-by-one between severe acute respiratory syndrome coronavirus (SARS-CoV) or bat coronavirus RaTG13 and SARS-CoV-2. The genomes of SARS-CoV-2 and RaTG13 were 77.9% and 77.7% identical to the genome of SARS-CoV, respectively. Seventeen of the 35 sites with insertion and/or deletion mutations between SARS-CoV-2 and SARS-CoV were based on insertion-and-deletion mutations with the replacement of 7-325 consecutive bases. Most of these long insertion-and-deletion sites were concentrated in the nonstructural protein 3 (Nsp3) gene of open reading frame (ORF) 1a, S1 domain of the spike protein, and ORF8 genes. Such long insertion-and-deletion mutations were not observed between the genomes of RaTG13 and SARS-CoV-2. The presence of multiple long insertion-and-deletion mutations in the genome of SARS-CoV-2 and their uneven distributions may provide further insights into the development of the virus.


Subject(s)
COVID-19 , Chiroptera , Animals , Chiroptera/genetics , Genome, Viral , Phylogeny , SARS-CoV-2/genetics , Sequence Deletion
6.
World J Pediatr ; 2022 Jun 04.
Article in English | MEDLINE | ID: covidwho-1877970

ABSTRACT

BACKGROUND: Coronavirus disease 2019 (COVID-19) has different manifestations in pediatric cases. It is assumed that they might present more gastrointestinal symptoms with a different viral shedding pattern in gastrointestinal samples. In this systematic review and meta-analysis, we aimed to evaluate the viral shedding pattern in gastrointestinal specimens of children with COVID-19. METHODS: We searched all published studies in English language in PubMed, Web of Science, and Scopus, up to date as of October 2021. Our search included the term "severe acute respiratory syndrome coronavirus 2, COVID-19, SARS-CoV-2, novel coronavirus, or coronavirus; and shed, excrete, secret, or carriage; and stool or rectal; and children or pediatrics". We included studies evaluating SARS-CoV-2 shedding in gastrointestinal specimens, including rectal swabs and stool samples of children with COVID-19 infection. We excluded duplicated data, case reports, and studies without original data. RESULTS: Twelve studies met the eligibility criteria for the qualitative synthesis, 10 of which were included in the meta-analysis. The pooled prevalence of gastrointestinal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in children with COVID-19 was 86% (95% confidence interval 73%-96%, I2 = 62.28%). After respiratory specimen had become negative, 72% (43/60) had persistent shedding in gastrointestinal specimens. The gastrointestinal RNA had a positive test result for more than 70 days after symptoms onset. CONCLUSIONS: Gastrointestinal shedding of SARS-CoV-2 might occur in a substantial portion of children and might persist long after negative respiratory testing. Further research is recommended to find the role of SARS-CoV-2 gastrointestinal shedding in transmission in children.

7.
Br J Haematol ; 2022 Jun 02.
Article in English | MEDLINE | ID: covidwho-1874397

ABSTRACT

Allogeneic haematopoietic stem cell transplant (HSCT) recipients remain at high risk of adverse outcomes from coronavirus disease 2019 (COVID-19) and emerging variants. The optimal prophylactic vaccine strategy for this cohort is not defined. T cell-mediated immunity is a critical component of graft-versus-tumour effect and in determining vaccine immunogenicity. Using validated anti-spike (S) immunoglobulin G (IgG) and S-specific interferon-gamma enzyme-linked immunospot (IFNγ-ELIspot) assays we analysed response to a two-dose vaccination schedule (either BNT162b2 or ChAdOx1) in 33 HSCT recipients at ≤2 years from transplant, alongside vaccine-matched healthy controls (HCs). After two vaccines, infection-naïve HSCT recipients had a significantly lower rate of seroconversion compared to infection-naïve HCs (25/32 HSCT vs. 39/39 HCs no responders) and had lower S-specific T-cell responses. The HSCT recipients who received BNT162b2 had a higher rate of seroconversion compared to ChAdOx1 (89% vs. 74%) and significantly higher anti-S IgG titres (p = 0.022). S-specific T-cell responses were seen after one vaccine in HCs and HSCT recipients. However, two vaccines enhanced S-specific T-cell responses in HCs but not in the majority of HSCT recipients. These data demonstrate limited immunogenicity of two-dose vaccination strategies in HSCT recipients, bolstering evidence of the need for additional boosters and/or alternative prophylactic measures in this group.

8.
J Med Virol ; 2022 Jun 02.
Article in English | MEDLINE | ID: covidwho-1872248

ABSTRACT

Assaying of anti-spike-protein receptor-binding domain (S-RBD) antibodies are used to aid evaluations of the immune statuses of individuals. The aim of this study was to determine the antibody response after two doses of homologous or heterologous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines and to identify the factors affecting this response among healthcare workers (HCWs) at health promotion centers. In this prospective observational study, 1095 consenting HCWs were recruited from 16 health checkup centers and were tested at T0 (day of first dose), T1-1 (1 month after first dose), T2-0 (day of second dose), T2-1 (1 month after second dose), and T2-3 (3 months after second dose). SARS-CoV-2 antibodies were measured using a chemiluminescence microparticle immunoassay with SARS-CoV-2 IgG II Quant in the ARCHITECT system (Abbott Diagnostics). At T1-1, anti-SARS-CoV-2 S-RBD IgG levels were significantly higher in participants who received messenger RNA (mRNA) vaccines than in those who received viral vector vaccines (p < 0.001). At T2-1, anti-SARS-CoV-2 S-RBD IgG levels were about 10 times higher than at T1-1 in participants who received homologous mRNA vaccines, which decreased to a third of those at T2-3. Anti-SARS-CoV-2 S-RBD IgG levels were highest among those who received homologous mRNA vaccines, followed by heterologous mRNA viral vector vaccines and homologous viral vector vaccines at T2-3 (p < 0.001). In a multivariable linear regression analysis, being female, taking at least one mRNA vaccine, and having a history of recovery from coronavirus disease 2019 (COVID-19) were significantly associated with anti-S-RBD levels. Anti-SARS-CoV-2 S-RBD IgG levels were decreased at 3 months after two-dose vaccinations and were associated with sex, vaccine type, and COVID-19 history.

9.
Biomedicines ; 10(6)2022 May 26.
Article in English | MEDLINE | ID: covidwho-1869465

ABSTRACT

Coronavirus disease 2019 (COVID-19) vaccines were developed a few months after the emergence of the pandemic. The first cases of vaccine-induced thrombotic complications after the use of adenoviral vector vaccines ChAdOx1 nCoV-19 by AstraZeneca, and Ad26.COV2.S by Johnson & Johnson/Janssen, were announced shortly after the initiation of a global vaccination program. In these cases, the occurrence of thrombotic events at unusual sites-predominantly located in the venous vascular system-in association with concomitant thrombocytopenia were observed. Since this new entity termed vaccine-induced thrombotic thrombocytopenia (VITT) shows similar pathophysiologic mechanisms as heparin-induced thrombocytopenia (HIT), including the presence of antibodies against heparin/platelet factor 4 (PF4), standard routine treatment for thrombotic events-arterial or venous-are not appropriate and may also cause severe harm in affected patients. Thrombotic complications were also rarely documented after vaccination with mRNA vaccines, but a typical VITT phenomenon has, to date, not been established for these vaccines. The aim of this review is to give a concise and feasible overview of diagnostic and therapeutic strategies in COVID-19 vaccine-induced thrombotic complications.

10.
J Biol Dyn ; 16(1): 412-438, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-1868208

ABSTRACT

We fit an SARS-CoV-2 model to US data of COVID-19 cases and deaths. We conclude that the model is not structurally identifiable. We make the model identifiable by prefixing some of the parameters from external information. Practical identifiability of the model through Monte Carlo simulations reveals that two of the parameters may not be practically identifiable. With thus identified parameters, we set up an optimal control problem with social distancing and isolation as control variables. We investigate two scenarios: the controls are applied for the entire duration and the controls are applied only for the period of time. Our results show that if the controls are applied early in the epidemic, the reduction in the infected classes is at least an order of magnitude higher compared to when controls are applied with 2-week delay. Further, removing the controls before the pandemic ends leads to rebound of the infected classes.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiology , Humans , Models, Biological , Monte Carlo Method , Pandemics/prevention & control
11.
J Pers Med ; 12(5)2022 May 14.
Article in English | MEDLINE | ID: covidwho-1855697

ABSTRACT

In comparison to Western European countries, Poland had a relatively lower percentage of its population diagnosed with COVID-19. Moreover, even the detected cases were not showing any pattern consistent with the expected chance of infection and were at best only remotely related to the severity of the illness that is known to increase with age. Instead, the crucial factor in detecting illness was whether the individual was likely to receive adequate compensation for being confined to their home, with employed women being the most likely to be diagnosed. In every Polish sub-region (powiat), in the 25-54 age group, the share of men diagnosed with COVID-19 was lower than that of women, with the missing share ranging from 8% to 36%. Based on the regression model (adjusted R² = 43.9%), there were relevant non-economic factors such as education, vaccination rate and increasing median age that were reducing this gap. However, the key factors, such as the share of population entitled to sick leave derived from employment rate, or the share of the self-employed population who were unlikely to receive adequate compensation, were related to economic incentives. It would seem that gender differences, in reaction to economic stimuli, widened the discrepancies, as the same factors were affecting women as well. While the testing rates in Poland, the lowest of all the EU countries, clearly played a role in creating the environment in which testing was perceived by the general population as somewhat optional, Polish citizens themselves through their actions aggravated the problem further, creating the impression of people receiving inadequate or no compensation for their time of self-isolation. In spite of well-intentioned government efforts to extend compensation to at least some groups, a significant share of the population clearly behaved as if they feared self-isolation more than the actual virus. Therefore, for both compliance and fairness purposes, both the severity of restrictions and the availability of compensation should be reconsidered.

12.
Biological & Pharmaceutical Bulletin ; 45(4):394-396, 2022.
Article in English | Web of Science | ID: covidwho-1848319

ABSTRACT

A novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain, the Omicron variant (Pango lineage B.1.1.529), was identified in South Africa in late September 2021. This variant has multiple spike protein deletions and mutations, with 15 amino acid substitutions detected in the receptor-binding domain (RBD). These RBD substitutions are hypothesized to increase infectivity and reduce antibody affinity, which is supported by recent data showing that the Omicron variant spreads faster than the Delta variant (Pango lineage B.1.617.2). Thus, this increase in infectivity should lead to Omicron being the dominant variant and developing screening tests that discriminate between Omicron and Delta variants is urgently needed. In this study, we successfully developed a novel screening assay using high-resolution melting analysis, in which two genotypes at G446/L452 and S477/T478 RBD were determined (G446S/L452 and S477N/T478K for Omicron;G446/I452R and S477/T478K for Delta). Using synthetic DNA fragments, we confirmed both melting point and melting peak shape of the RBD Omicron variant was distinguishable from those of wild-type and the Delta variant. Although this study was conducted without clinical samples, these results suggest that our high-resolution melting (HRM)based genotyping method can readily identify the Omicron and Delta variants. This simple method should contribute to the rapid identification of SARS-CoV-2 variants and thus prevent potential widespread infection and inflow of the Omicron variant.

13.
Euro Surveill ; 27(19)2022 05.
Article in English | MEDLINE | ID: covidwho-1847113

ABSTRACT

BackgroundMycoplasma pneumoniae respiratory infections are transmitted by aerosol and droplets in close contact.AimWe investigated global M. pneumoniae incidence after implementation of non-pharmaceutical interventions (NPIs) against COVID-19 in March 2020.MethodsWe surveyed M. pneumoniae detections from laboratories and surveillance systems (national or regional) across the world from 1 April 2020 to 31 March 2021 and compared them with cases from corresponding months between 2017 and 2020. Macrolide-resistant M. pneumoniae (MRMp) data were collected from 1 April 2017 to 31 March 2021.ResultsThirty-seven sites from 21 countries in Europe, Asia, America and Oceania submitted valid datasets (631,104 tests). Among the 30,617 M. pneumoniae detections, 62.39% were based on direct test methods (predominantly PCR), 34.24% on a combination of PCR and serology (no distinction between methods) and 3.37% on serology alone (only IgM considered). In all countries, M. pneumoniae incidence by direct test methods declined significantly after implementation of NPIs with a mean of 1.69% (SD ± 3.30) compared with 8.61% (SD ± 10.62) in previous years (p < 0.01). Detection rates decreased with direct but not with indirect test methods (serology) (-93.51% vs + 18.08%; p < 0.01). Direct detections remained low worldwide throughout April 2020 to March 2021 despite widely differing lockdown or school closure periods. Seven sites (Europe, Asia and America) reported MRMp detections in one of 22 investigated cases in April 2020 to March 2021 and 176 of 762 (23.10%) in previous years (p = 0.04).ConclusionsThis comprehensive collection of M. pneumoniae detections worldwide shows correlation between COVID-19 NPIs and significantly reduced detection numbers.


Subject(s)
COVID-19 , Pneumonia, Mycoplasma , COVID-19/epidemiology , Communicable Disease Control , Humans , Macrolides , Mycoplasma pneumoniae/genetics , Pandemics , Pneumonia, Mycoplasma/diagnosis , Pneumonia, Mycoplasma/epidemiology
14.
Tohoku J Exp Med ; 257(1): 1-6, 2022 May 13.
Article in English | MEDLINE | ID: covidwho-1847008

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remained a major global health concern in 2021. To suppress the spread of infection, mass vaccinations have been performed across countries worldwide. In Japan, vaccinations of the first and second doses for most of the nation were performed during the nationwide outbreak of the B.1.617.2 (Delta) variant with the L452R spike protein mutation, and the effectiveness of the vaccinations to suppress the spread of COVID-19 among the people in Japan remains uncertain. In this study, adults aged ≥18 years, who were in contact with patients with COVID-19 and underwent nasopharyngeal swab reverse transcription-polymerase chain reaction (RT-PCR) tests during August and September 2021 at a mass screening test center in Japan, were enrolled. In this period, more than 95% of the COVID-19 infections were reportedly caused by the Delta variant. As a result, a total of 784 adults with recent contact history, including 231 (29.5%) RT-PCR test-positive cases, were enrolled. The test positivity rate was lower in individuals who had been vaccinated twice than in unvaccinated individuals (12.5% vs. 39.0%, p < 0.0001), with the risk ratio of 0.32 (95% confidence interval 0.23-0.46). The vaccine effectiveness was the highest between 7-90 days after the second vaccine dose. In conclusion, two doses of mRNA COVID-19 vaccines effectively suppressed transmission in Japan during the nationwide pandemic of the Delta variant, estimated to have prevented 50-80% of the infection.


Subject(s)
COVID-19 Vaccines , COVID-19 , Adolescent , Adult , COVID-19/epidemiology , COVID-19/prevention & control , Humans , Japan/epidemiology , Pandemics , RNA, Messenger , SARS-CoV-2/genetics
15.
Pakistan Armed Forces Medical Journal ; 72(1):91-96, 2022.
Article in English | Scopus | ID: covidwho-1841856

ABSTRACT

Objective: To share the epidemiological, clinical and laboratory -based evidence of severe acute respiratory syndrome Corona Virus-2 with focus on the cases of re-infection;an update after one year of the ongoing pandemic. Study Design: Prospective observational study. Place and Duration of Study: Department of Pathology, in collaboration with Department of Medicine, Combined Military Hospital, Malir, from Mar 2020 to Feb 2021. Methodology: Total 5190 nasopharyngeal swabs were collected and transported to the laboratory in viral transport media for severe acute respiratory syndrome Corona Virus-2, from all symptomatic patients with a history of exposure/traveling from endemic areas and those requiring admission in hospital and were screened for COVID-19 as per hospital standing protocols. Results: 561(10.8%) patients were PCR positive for severe acute respiratory syndrome Corona Virus-2. The mean age of patients was 39.45±31.9 years and a majority of patients were males 426 (76%). The most common symptoms were fever and dry cough followed by myalgia and shortness of breath. 37 (9%) patients died due to the severity of the illness. Total 6 (1.46%) cases of laboratory-confirmed reinfection of severe acute respiratory syndrome Corona Virus-2 were reported. 2(33%) cases of reinfection were observed in health care workers, mortality was seen in a single patient associated with old age and comorbidities. Conclusion: In our study, the severity of the disease was directly related to the age of patients and underlying comorbidities. Reinfection was associated with increased viral load and exposure to the infected environment. © 2022, Army Medical College. All rights reserved.

16.
AMB Express ; 12(1), 2022.
Article in English | ProQuest Central | ID: covidwho-1837317

ABSTRACT

As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to spread globally, a series of vaccines, antibodies and drugs have been developed to combat coronavirus disease 2019 (COVID-19). High specific antibodies are powerful tool for the development of immunoassay and providing passive immunotherapy against SARS-CoV-2 and expected with large scale production. SARS-CoV-2 S1 protein was expressed in E. coli BL21 and purified by immobilized metal affinity chromatography, as antigen used to immunize hens, the specific IgY antibodies were extracted form egg yolk by PEG-6000 precipitation, and the titer of anti-S1 IgY antibody reached 1:10,000. IgY single chain variable fragment antibody (IgY-scFv) was generated by using phage display technology and the IgY-scFv showed high binding sensitivity and capacity to S1 protein of SARS-CoV-2, and the minimum detectable antigen S1 protein concentration was 6 ng/µL. The docking study showed that the multiple epitopes on the IgY-scFv interacted with multiple residues on SARS-CoV-2 S1 RBD to form hydrogen bonds. This preliminary study suggests that IgY and IgY-scFv are suitable candidates for the development of immunoassay and passive immunotherapy for COVID-19 to humans and animals.

17.
Acta Chir Belg ; : 1-4, 2021 Dec 27.
Article in English | MEDLINE | ID: covidwho-1830336

ABSTRACT

INTRODUCTION: Vaccine-induced thrombocytopenia and thrombosis (VITT) is a rare but devastating adverse event associated with the ChAdOx1 nCoV-19 (Oxford-AstraZeneca) adenoviral vaccine against the Severe Acute Respiratory Syndrome CoronaVirus-2 (SARS-CoV-2). METHODS: A 49-year-old man presented to the emergency department with acute right limb ischemia (Rutherford IIB) nine days after his ChAdOx1 nCoV-19 (Oxford-AstraZeneca) vaccination. CT angiography revealed significant aortic thrombosis and right femoral artery occlusion. Severe thrombocytopenia (platelet count of 23 × 103/µL), promptly elevated D-dimers (37937 ng/mL) and a reduced fibrinogen level (176 mg/dL) were remarkable. ELISA testing for anti-PF4 antibodies confirmed the diagnosis of VITT. RESULTS: An emergency revascularization of the right leg was provided via thrombectomy. High-dose intravenous immunoglobulins were administered whereafter the platelet count restored gradually. Therapeutic anticoagulation was progressively started. The postoperative course was uneventful and follow-up imaging after four weeks showed an almost complete resolution of the significant aortic thrombosis. CONCLUSION: Early recognition and appropriate counseling of VITT is advocated to pursue a good clinical outcome. Our patient presenting with severe aortic thrombosis and acute limb ischemia was successfully treated by a vascular thrombectomy along with intravenous immunoglobulins and anticoagulation therapy as the mainstay therapy.

18.
Acta Medica Iranica ; 60(4):202-209, 2022.
Article in English | Academic Search Complete | ID: covidwho-1824333

ABSTRACT

The coronavirus disease 2019 (COVID-19) is a single-stranded RNA (+) virus and causes infectious disease by the viral strain "severe acute respiratory syndrome coronavirus 2" (SARS-CoV-2). Now, COVID-19 has become pandemic, and there are neither potential vaccines nor drugs discovered. Its RNA contains genes for structural (S, E, M, N) and non-structural proteins (PLpro, 3CLpro, RdRp, Hel). Interaction between the S protein of SARS-CoV-2 and the ACE 2 receptor of the host cell plays a vital role in the entry of the virus into the cell. Favipiravir, ribavirin, remdesivir, galidesivir, lopinavir, ritonavir, chloroquine, and hydroxychloroquine are the few effective drugs against SARS-CoV-2. Live attenuated virus (mutant MERS-CoV and SARS-CoV or recombination with another live attenuated virus) can act as vaccine platforms against SARS CoV-2 along with DNA vaccine and subunit vaccine. [ FROM AUTHOR] Copyright of Acta Medica Iranica is the property of Tehran University of Medical Sciences 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.)

19.
World J Pediatr ; 2022 May 04.
Article in English | MEDLINE | ID: covidwho-1821006

ABSTRACT

BACKGROUND: There are limited numbers of studies focusing on renal effects of coronavirus disease 2019 (COVID-19) infection and proximal tubular dysfunction in children with COVID-19 infections. The purpose of this study was to evaluate the functions of the proximal tubule in hospitalized children with confirmed acute COVID-19. METHODS: The children who were hospitalized for confirmed COVID-19 were included in this prospective descriptive analysis. The presence of at least two of the following four abnormalities was used to diagnose proximal tubule injury: abnormal tubular reabsorption of phosphate, normoglycemic glycosuria, hyperuricosuria, and proteinuria. RESULTS: A total of 115 patients were included in the study. About a third of the individuals had elevated blood creatinine levels or proteinuria. In addition, abnormal renal tubular phosphate loss measured by renal tubular phosphate loss was found in 10 (8.7%) patients, as was hyperuricosuria in 28.6%. As a result, total proximal tubular dysfunction was found in 24 (20.9%) patients. CONCLUSIONS: One in every five children with acute COVID-19 infections had proximal tubular dysfunction, according to our data. Although, the rate of proximal tubular dysfunction was lower than in adults, it should be noted. The recovery of proximal tubular function in children with COVID-19 should be followed.

20.
Cells ; 11(9)2022 04 21.
Article in English | MEDLINE | ID: covidwho-1818055

ABSTRACT

Human SARS-CoV-2 and avian infectious bronchitis virus (IBV) are highly contagious and deadly coronaviruses, causing devastating respiratory diseases in humans and chickens. The lack of effective therapeutics exacerbates the impact of outbreaks associated with SARS-CoV-2 and IBV infections. Thus, novel drugs or therapeutic agents are highly in demand for controlling viral transmission and disease progression. Mesenchymal stem cells (MSC) secreted factors (secretome) are safe and efficient alternatives to stem cells in MSC-based therapies. This study aimed to investigate the antiviral potentials of human Wharton's jelly MSC secretome (hWJ-MSC-S) against SARS-CoV-2 and IBV infections in vitro and in ovo. The half-maximal inhibitory concentrations (IC50), cytotoxic concentration (CC50), and selective index (SI) values of hWJ-MSC-S were determined using Vero-E6 cells. The virucidal, anti-adsorption, and anti-replication antiviral mechanisms of hWJ-MSC-S were evaluated. The hWJ-MSC-S significantly inhibited infection of SARS-CoV-2 and IBV, without affecting the viability of cells and embryos. Interestingly, hWJ-MSC-S reduced viral infection by >90%, in vitro. The IC50 and SI of hWJ-MSC secretome against SARS-CoV-2 were 166.6 and 235.29 µg/mL, respectively, while for IBV, IC50 and SI were 439.9 and 89.11 µg/mL, respectively. The virucidal and anti-replication antiviral effects of hWJ-MSC-S were very prominent compared to the anti-adsorption effect. In the in ovo model, hWJ-MSC-S reduced IBV titer by >99%. Liquid chromatography-tandem mass spectrometry (LC/MS-MS) analysis of hWJ-MSC-S revealed a significant enrichment of immunomodulatory and antiviral proteins. Collectively, our results not only uncovered the antiviral potency of hWJ-MSC-S against SARS-CoV-2 and IBV, but also described the mechanism by which hWJ-MSC-S inhibits viral infection. These findings indicate that hWJ-MSC-S could be utilized in future pre-clinical and clinical studies to develop effective therapeutic approaches against human COVID-19 and avian IB respiratory diseases.


Subject(s)
Bronchitis , COVID-19 , Mesenchymal Stem Cells , Wharton Jelly , Animals , Antiviral Agents/metabolism , Antiviral Agents/pharmacology , Bronchitis/metabolism , Chickens , Humans , Immunologic Factors/metabolism , Mesenchymal Stem Cells/metabolism , SARS-CoV-2 , Wharton Jelly/metabolism
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