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991.
Does prior immunization with measles,mumps, and rubella vaccines contribute to the antibody response to COVID-19 antigens?
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Danesh HassaniMohammad Mehdi AmiriFaezeh MaghsoodVahid SalimiGholam Ali KardarOmid BaratiSeyed Mohammad Reza HashemianMahmood Jeddi-TehraniAmir-Hassan ZarnaniFazel Shokri 《Iranian journal of immunology : IJI》2021,18(1):47-53
Background: Incidence and severity of SARS-CoV2 infection are significantly lower in children and teenagers proposing that certain vaccines, routinely administered to neonates and children may provide cross-protection against this emerging infection. Objective: To assess the cross-protection induced by prior measles, mumps and rubella (MMR) vaccinations against COVID-19. Methods: The antibody responses to MMR and tetanus vaccines were determined in 53 patients affected with SARS-CoV2 infection and 52 age-matched healthy subjects. Serum levels of antibodies specific for NP and RBD of SARS-CoV2 were also determined in both groups of subjects with ELISA. Results: Our results revealed significant differences in anti-NP (p <0.0001) and anti-RBD (p <0.0001) IgG levels between patients and healthy controls. While the levels of rubella- and mumps specific IgG were not different in the two groups of subjects, measles-specific IgG was significantly higher in patients (p <0.01). The serum titer of anti-tetanus antibody, however, was significantly lower in patients compared to healthy individuals (p <0.01). Conclusion: Our findings suggest that measles vaccination triggers those B cells cross-reactive with SARS-CoV2 antigens leading to the production of increased levels of measles-specific antibody. 相似文献
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993.
Nadim Sharif Rubayet Rayhan Opu Shamsun Nahar Ahmed Mithun Kumar Sarkar Raisah Jaheen Muktasid Ud Daullah Shahriar Khan Mir Mubin Habibur Rahman Faiza Islam Nusaira Haque Suchana Islam Fariha Bushra Khan Nabila Haque Umme Ayman Abdullah Mohammad Shohael Shuvra Kanti Dey Ali Azam Talukder 《Diabetes & Metabolic Syndrome: Clinical Research & Reviews》2021,15(4):102148
BackgroundSocio-demographics and comorbidities are involved in determining the severity and fatality in patients with COVID-19 suggested by studies in various countries, but study in Bangladesh is insufficient.AimsWe designed the study to evaluate the association of sociodemographic and comorbidities with the prognosis of adverse health outcomes in patients with COVID-19 in Bangladesh.MethodsA multivariate retrospective cohort study was conducted on data from 966 RT-PCR positive patients from eight divisions during December 13, 2020, to February 13, 2021. Variables included sociodemographic, comorbidities, symptoms, Charlson comorbidity index (CCI) and access to health facilities. Major outcome was fatality. Secondary outcomes included hospitalization, duration of hospital stay, requirement of mechanical ventilation and severity.ResultsMale (65.8%, 636 of 966) was predominant and mean age was 39.8 ± 12.6 years. Fever (79%), dry cough (55%), and loss of test/smell (51%) were frequent and 74% patients had >3 symptoms. Fatality was recorded in 10.5% patients. Comorbidities were found in 44% patients. Hypertension (21.5%) diabetes (14.6%), and cardiovascular diseases (11.3%) were most prevalent. Age >60 years (OR: 4.83, 95% CI: 2.45–6.49), and CCI >3 (OR: 5.48, 95% CI: 3.95–7.24) were predictors of hospitalizations. CCI >4 (aOR: 3.41, 95% CI: 2.57–6.09) was predictor of severity. Age >60 years (aOR: 3.77, 95% CI: 1.07–6.34), >3 symptoms (aOR: 2.14, 95% CI: 0.97–4.91) and CCI >3 vs. CCI <3 (aOR: 5.23, 95% CI: 3.77–8.09) were independently associated with fatality.ConclusionsIncreased age, >3 symptoms, increasing comorbidities, higher CCI were associated with increased hospitalization, severity and fatality in patients with COVID-19. 相似文献
994.
Sanaz Jamshidi Yousef Moradi Ghazaleh Nameni Mohammad Ali Mohsenpour Mohammadreza Vafa 《Diabetes & Metabolic Syndrome: Clinical Research & Reviews》2021,15(2):605-613
Background and aimsPresent meta-analysis and systematic review was conducted to synthesis a definitive conclusion from previous randomized controlled clinical trials (RCTs).MethodsA comprehensive search was done up to July 2020, in order to extract RCTs which investigated the effect of cashew nut on weight, body mass index (BMI), waist circumference (WC), fasting blood sugar (FBS), insulin, and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR). Weighted mean difference (WMD) and 95% confidence interval (CI) were used to estimate effect size. Meta regression analysis was done to identify probable sources of heterogeneity.ResultsSix clinical trials with 521 participants were included. Combined effect sizes demonstrated no effect of cashew consumption on weight (WMD): 0.02, 95% CI: ?1.04, 1.09, P > 0.05), BMI (WMD: 0.1, 95% CI: ?0.72, 0.74, P > 0.05), and WC (WMD: ?0.13, 95% CI: ?1.97, 1.70, P > 0.05). Results were also not significant for FBS (WMD: 3.58, 95% CI: ?3.92, 11.08, P > 0.05), insulin (WMD: ?0.19, 95% CI: ?1.63, 1.25, P > 0.05), and HOMA-IR (WMD: 0.25, 95% CI: ?0.55, 1.06, P > 0.05).ConclusionThe sum up, incorporating cashew into the diet has no significant effect on body composition or modifying glycemic indices. 相似文献
995.
996.
997.
Bayarchimeg Altankhishig Mohammad Ali Akbor Polan Youjing Qiu Md Riasat Hasan Takashi Saito 《Materials》2021,14(4)
The purpose of the present study was to investigate the effect of a peptide (i.e., SESDNNSSSRGDASYNSDES) derived from dentin phosphophoryn (DPP) with arginine-glycine-aspartic acid (RGD) motifs on odontoblast differentiation in vitro and to compare it with calcium hydroxide—a material used conventionally for vital pulp therapy—in terms of reparative dentin formation and pulp inflammation in vivo. Alkaline phosphatase activity assay and alizarin red S staining were performed to evaluate odontoblast-differentiation in cell culturing experiments. To observe the reparative dentin formation and pulp inflammation animal experiment was performed and examined by histological methods. The difference between the experimental group and the control group was analyzed statistically using a one-way ANOVA test. The results revealed that the DPP-derived RGD-containing peptide triggered odontoblast differentiation and mineralization in vitro. In rats undergoing direct pulp capping, the DPP-derived RGD-containing peptide was found to induce intensively formed reparative dentin with high compactness at week 4. On histological and morphometrical examinations, a smaller degree of pulpitis was observed in the specimens treated with the peptide than in those treated with calcium hydroxide. This study suggests that the DPP-derived RGD-containing peptide is a biocompatible, biodegradable and bioactive material for dentin regeneration. 相似文献
998.
Na Ta Muhammad Umer Bilal Ines Husler Alaukik Saxena Yueh-Yu Lin Felix Schleifer Michael Fleck Uwe Glatzel Birgit Skrotzki Reza Darvishi Kamachali 《Materials》2021,14(5)
The effects of anisotropic interfacial properties and heterogeneous elasticity on the growth and ripening of plate-like θ′-phase (Al2Cu) in Al-1.69 at.% Cu alloy are studied. Multi-phase-field simulations are conducted and discussed in comparison with aging experiments. The precipitate/matrix interface is considered to be anisotropic in terms of its energy and mobility. We find that the additional incorporation of an anisotropic interfacial mobility in conjunction with the elastic anisotropy result in substantially larger aspect ratios of the precipitates closer to the experimental observations. The anisotropy of the interfacial energy shows comparably small effect on the precipitate’s aspect ratio but changes the interface’s shape at the rim. The effect of the chemo-mechanical coupling, i.e., the composition dependence of the elastic constants, is studied as well. We show that the inverse ripening phenomenon, recently evidenced for δ’ precipitates in Al-Li alloys (Park et al. Sci. Rep. 2019, 9, 3981), does not establish for the θ′ precipitates. This is because of the anisotropic stress fields built around the θ′ precipitates, stemming from the precipitate’s shape and the interaction among different variants of the θ′ precipitate, that disturb the chemo-mechanical effects. These results show that the chemo-mechanical effects on the precipitation ripening strongly depend on the degree of sphericity and elastic isotropy of the precipitate and matrix phases. 相似文献
999.
Structural Response of Steel Jacket-UHPC Retrofitted Reinforced Concrete Columns under Blast Loading
The lateral capacity of exterior concrete columns subjected to a blast load is the key factor in the building collapse probability. Due to potentially severe consequences of the collapse, efforts have been made to improve the blast resistance of existing structures. One of the successful approaches is the use of ultra-high-performance-concrete (UHPC) jacketing for retrofitting a building’s columns. The columns on the first floor of a building normally have higher slenderness due to the higher first story. Since an explosion is more likely to take place at the ground level, retrofitting the columns of the lower floors is crucial to improve a building’s blast resistance. Casting a UHPC tube around a circular RC column can increase the moment of inertia of the column and improve the flexural strength. In this study, a retrofitting system consisting of a UHPC layer enclosed by a thin steel jacket is proposed to improve the blast resistance of buildings in service. Most of the previous research is focused on design aspects of blast-resistant columns and retrofitting systems are mostly based on fiber reinforced polymers or steel jackets. A validated FE model is used to investigate the effectiveness of this method. The results showed significant improvement both at the component and building system levels against combined gravity and blast loading. 相似文献