9 results on '"van der Kieft R"'
Search Results
2. Longitudinal Follow-Up of the Immunity to SARS-CoV-2 in Health Care Workers in Argentina: Persistence of Humoral Response and Neutralizing Capacity after Sputnik V Vaccination.
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Castro, Eliana F., Acosta, Julián, Moriena, Lucía, Medrano, Mayra Rios, Cibello, Malena Tejerina, Codino, Eduardo, Taborda, Miguel Ángel, Álvarez, Diego E., and Cavatorta, Ana Laura
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- 2023
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3. Impaired SARS-CoV-2 specific T-cell response in patients with severe COVID-19.
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Rümke, Lidewij W., Smit, Wouter L., Bossink, Ailko, Limonard, Gijs J. M., Muilwijk, Danya, Haas, Lenneke E. M., Reusken, Chantal, van der Wal, Sanne, Thio, Bing J., van Os, Yvonne M. G., Gremmels, Hendrik, Beekman, Jeffrey M., Nijhuis, Monique, Wensing, Annemarie M. J., Heron, Michiel, and Thijsen, Steven F. T.
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COVID-19 ,SARS-CoV-2 ,ACUTE phase reaction ,T cells ,MEMBRANE proteins - Abstract
Cellular immune responses are of pivotal importance to understand SARS-CoV-2 pathogenicity. Using an enzyme-linked immunosorbent spot (ELISpot) interferon-g release assay with wild-type spike, membrane and nucleocapsid peptide pools, we longitudinally characterized functional SARS-CoV-2 specific T-cell responses in a cohort of patients with mild, moderate and severe COVID-19. All patients were included before emergence of the Omicron (B.1.1.529) variant. Our most important finding was an impaired development of early IFN-γ-secreting virus-specific T-cells in severe patients compared to patients with moderate disease, indicating that absence of virus-specific cellular responses in the acute phase may act as a prognostic factor for severe disease. Remarkably, in addition to reactivity against the spike protein, a substantial proportion of the SARS-CoV-2 specific T-cell response was directed against the conserved membrane protein. This may be relevant for diagnostics and vaccine design, especially considering new variants with heavily mutated spike proteins. Our data further strengthen the hypothesis that dysregulated adaptive immunity plays a central role in COVID-19 immunopathogenesis. [ABSTRACT FROM AUTHOR]
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- 2023
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4. Measuring T-Cell Responses against SARS-CoV-2 Is of Utility for Disease and Vaccination Management.
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Safont, Guillem, Latorre, Irene, Villar-Hernández, Raquel, Stojanovic, Zoran, Marín, Alicia, Pérez-Cano, Cristina, Lacoma, Alicia, Molina-Moya, Bárbara, Solis, Alan Jhunior, Arméstar, Fernando, Matllo, Joan, Díaz-Fernández, Sergio, Cendón, Arnau, Sokalchuk, Liliya, Tolosa, Guillermo, Casas, Irma, Rosell, Antoni, and Domínguez, José
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DISEASE management ,T cells ,SARS-CoV-2 ,COVID-19 ,VACCINATION status - Abstract
The measurement of specific T-cell responses can be a useful tool for COVID-19 diagnostics and clinical management. In this study, we evaluated the IFN-γ T-cell response against the main SARS-CoV-2 antigens (spike, nucleocapsid and membrane) in acute and convalescent individuals classified according to severity, and in vaccinated and unvaccinated controls. IgG against spike and nucleocapsid were also measured. Spike antigen triggered the highest number of T-cell responses. Acute patients showed a low percentage of positive responses when compared to convalescent (71.6% vs. 91.7%, respectively), but increased during hospitalization and with severity. Some convalescent patients showed an IFN-γ T-cell response more than 200 days after diagnosis. Only half of the vaccinated individuals displayed an IFN-γ T-cell response after the second dose. IgG response was found in a higher percentage of individuals compared to IFN-γ T-cell responses, and moderate correlations between both responses were seen. However, in some acute COVID-19 patients specific T-cell response was detected, but not IgG production. We found that the chances of an IFN-γ T-cell response against SARS-CoV-2 is low during acute phase, but may increase over time, and that only half of the vaccinated individuals had an IFN-γ T-cell response after the second dose. [ABSTRACT FROM AUTHOR]
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- 2022
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5. The Safety of Cold-Chain Food in Post-COVID-19 Pandemic: Precaution and Quarantine.
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Kong, Jia, Li, Wenxin, Hu, Jinyao, Zhao, Shixuan, Yue, Tianli, Li, Zhonghong, and Xia, Yinqiang
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SARS-CoV-2 ,COVID-19 ,FOOD safety ,COVID-19 pandemic ,FOOD contamination ,QUARANTINE - Abstract
Since the outbreak of coronavirus disease-19 (COVID-19), cold-chain food contamination caused by the pathogenic severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has attracted huge concern. Cold-chain foods provide a congenial environment for SARS-CoV-2 survival, which presents a potential risk for public health. Strengthening the SARS-CoV-2 supervision of cold-chain foods has become the top priority in many countries. Methodologically, the potential safety risks and precaution measures of SARS-CoV-2 contamination on cold-chain food are analyzed. To ensure the safety of cold-chain foods, the advances in SARS-CoV-2 detection strategies are summarized based on technical principles and target biomarkers. In particular, the techniques suitable for SARS-CoV-2 detection in a cold-chain environment are discussed. Although many quarantine techniques are available, the field-based quarantine technique on cold-chain food with characteristics of real-time, sensitive, specific, portable, and large-scale application is urgently needed. [ABSTRACT FROM AUTHOR]
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- 2022
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6. Abnormal Transcript Levels of Cytokines Among Iranian COVID-19 Patients.
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Samsami, Majid, Fatemi, Alireza, Jalili Khoshnoud, Reza, Kohansal, Karim, Hussen, Bashdar Mahmud, Soghala, Shabnam, Taheri, Mohammad, and Ghafouri-Fard, Soudeh
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The pandemic caused by severe acute respiratory syndrome coronavirus 2 and the related disorder i.e. "coronavirus disease 2019" (COVID-19) has encouraged researchers to unravel the molecular mechanism of disease severity. Several lines of evidence support the impact of "cytokine storm" in the pathogenesis of severe forms of the disorder. We aimed to assess expression levels of nine cytokine coding genes in COVID-19 patients admitted in a hospital. We collected clinical data of patients from their medical reports. Then, we assessed expression of genes using real-time PCR. Expression levels of IFN-G, IL-2, IL-4, IL-6, IL-17, TGF-B, IL-8, and IL-1B were significantly higher in COVID-19 patients compared with healthy controls and in both female and male patients compared with sex-matched controls. However, expression level of TNF-A was not different between COVID-19 patients and healthy controls. Expression of none of these cytokines was different between ICU-admitted patients and other patients except for IL-6 whose expression was lower in the former group compared with the latter (ratio of means = 0.33, P value = 4.82E-02). Then, we assessed diagnostic power of cytokine coding genes in differentiating between COVID-19 patients and controls. The area under curve (AUC) values ranged from 0.94 for IFN-G to 1.0 for IL-2 and IL-1B. After combining the transcript levels of all cytokines, AUC, sensitivity, and specificity values reached 100%, 100%, and 99%, respectively. For differentiation between ICU-admitted patients and other patients, IL-4 with AUC value of 0.68 had the best diagnostic power among cytokine coding genes. Expression of none of cytokine coding genes was correlated with the available clinical/demographic data including age, gender, ICU admission, or erythrocyte sedimentation rate (ESR)/C-reactive protein (CRP) levels. This study provides further evidence for contribution of "cytokine storm" in the pathobiology of moderate/severe forms of COVID-19. [ABSTRACT FROM AUTHOR]
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- 2022
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7. Quantitative Insight into Immunopathology of SARS-CoV-2 Infection.
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Soni, Bhavnita, Kabra, Ritika, and Singh, Shailza
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SARS-CoV-2 ,COVID-19 pandemic ,IMMUNOPATHOLOGY ,VACCINE development ,VACCINE effectiveness ,COVID-19 - Abstract
Severe Acute Respiratory Syndrome-Coronavirus (SARS-CoV-2), which initiated as an endemic from China, converted into a pandemic disease worldwide within a couple of months' time. This has led researchers from all over the world to come together to find and develop possible curative or preventive strategies, including vaccine development, drug repurposing, plasma therapy, drug discovery, and cytokine-based therapies. Herein, we are providing, a summarized overview of immunopathology of the SARS-CoV-2 along with various therapeutic strategies undertaken to COVID-19 with a vision for their possible outcome. High levels of proinflammatory cytokines such as interleukin (IL)-7, G-CSF, IP-10, TNF-α, monocyte chemoattractant protein-1 (MCP-1), and IL-2 in severe cases of COVID-19 have been observed. Immune responses play significant roles in the determination of SARS-CoV-2 pathogenesis. Thus, exploring the underlying mechanism of the immune system response to SARS-CoV-2 infection would help in the prediction of disease course and selection of intensive care and therapeutic strategy. As an effort toward developing possible therapeutics for COVID-19, we highlighted different types of vaccines, which are under clinical trials, and also discussed the impact of genome variability on efficacy of vaccine under development. [ABSTRACT FROM AUTHOR]
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- 2021
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8. Cellular Immunity in COVID-19 Convalescents with PCR-Confirmed Infection but with Undetectable SARS-CoV-2-Specific IgG.
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Schwarzkopf, Sina, Krawczyk, Adalbert, Knop, Dietmar, Klump, Hannes, Heinold, Andreas, Heinemann, Falko M., Thümmler, Laura, Temme, Christian, Breyer, Marianne, Witzke, Oliver, Dittmer, Ulf, Lenz, Veronika, Horn, Peter A., and Lindemann, Monika
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We investigated immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among a group of convalescent, potential blood donors in Germany who had PCR-confirmed SARS-CoV-2 infection. Sixty days after onset of symptoms, 13/78 (17%) study participants had borderline or negative results to an ELISA detecting IgG against the S1 protein of SARS-CoV-2. We analyzed participants with PCR-confirmed infection who had strong antibody responses (ratio >3) as positive controls and participants without symptoms of SARS-CoV-2 infection and without household contact with infected patients as negative controls. Using interferon-γ ELISpot, we observed that 78% of PCR-positive volunteers with undetectable antibodies showed T-cell immunity against SARS-CoV-2. We observed a similar frequency (80%) of T-cell immunity in convalescent donors with strong antibody responses but did not detect immunity in negative controls. We concluded that, in convalescent patients with undetectable SARS-CoV-2 IgG, immunity may be mediated through T cells. [ABSTRACT FROM AUTHOR]
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- 2021
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9. Untitled.
- Author
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Kieft, Schreel, van der Plas, and Rindt
- Abstract
A 3D particle-tracking velocimetry (PTV) algorithm is applied to the wake flow behind a heated cylinder. The method is tested in advance with respect to its accuracy and performance. In the accuracy tests, its capability to locate particles in 3D space is tested. It appears that the algorithm can determine the particle position with an accuracy of less than 0.5 camera pixels, equivalent to 0.3 mm in the present test situation. The performance tests show that for particles located in a 2D plane, the algorithm can track the particles with a vector yield reaching 100%, which means that a velocity vector can be determined for almost all particles detected. The calculated velocity vectors for this situation have a standard deviation of less than 1%. The performance is also tested on a mixed convection flow behind a heated cylinder in which the 2D flow transits into a 3D flow. As there is no exact solution of such a flow available, the 3D PTV results are compared with visualisation results. The results show that the 3D PTV method can capture the main features of the 3D transition of the 2D vortex street. [ABSTRACT FROM AUTHOR]
- Published
- 2002
- Full Text
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