Search results for " Neutral"
showing 10 items of 654 documents
Neutralizing antibodies against SARS-CoV-2 variants of concern elicited by the comirnaty COVID-19 vaccine in nursing home residents.
2022
Immunosenescence may impact the functionality and breadth of vaccine-elicited humoral immune responses. The ability of sera to neutralize the SARS-CoV-2 spike protein (S) from Beta, Gamma, Delta, and Epsilon variants of concern (VOCs) relative to the ancestral Wuhan-Hu-1 strain was compared in Comirnaty COVID-19-vaccinated elderly nursing home residents, either SARS-CoV-2 naïve (n = 22) or experienced (n = 8), or SARS-CoV-2 naïve younger individuals (n = 18) and non-vaccinated individuals who recovered from severe COVID-19 (n = 19). In all groups, except that including SARS-CoV-2-experienced nursing home residents, some participants lacked NtAb against one or more VOCs, mainly the Beta vari…
Role of cytomegalovirus (CMV)-specific polyfunctional CD8+ T-cells and antibodies neutralizing virus epithelial infection in the control of CMV infec…
2015
The role of cytomegalovirus (CMV)-specific polyfunctional CD8+ T-cells and that of antibodies neutralizing virus epithelial infection (AbNEI) in the control of CMV DNAemia were investigated in 39 CMV-seropositive allogeneic stem-cell transplant (Allo-SCT) recipients with (n = 24) or without (n = 15) CMV DNAemia. AbNEI levels were monitored prospectively by means of a neutralization assay employing retinal epithelial cells (ARPE-19) and the recombinant CMV strain BADrUL131-Y4. Quantification of CMV-specific polyfunctional CD8+ T-cells (expressing two or three of the following markers: IFN-γγ, TNF-α and CD107a) in whole blood was performed by flow cytometry for intracellular cytokine staining…
Neutralization of SARS-CoV-2 lineage B.1.1.7 pseudovirus by BNT162b2 vaccine–elicited human sera
2021
Vaccine protects against B1.1.7 variant The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B1.1.7 (VOC 202012/01) variant that emerged in late 2020 in the United Kingdom has many changes in the spike protein gene. Three of these are associated with enhanced infectivity and transmissibility, and there are concerns that B.1.1.7 might compromise the effectiveness of the vaccine. Muik et al. compared the neutralization efficacy of sera from 40 subjects immunized with the BioNTech-Pfizer mRNA vaccine BNT162b2 against a pseudovirus bearing the Wuhan reference strain or the lineage B.1.1.7 spike protein (see the Perspective by Altmann et al.). Serum was derived from 40 subjects in tw…
Seroprevalence of Aichi Virus in a Spanish Population from 2007 to 2008
2010
ABSTRACT Viruses are among the most common causes of acute gastroenteritis. In recent years, new viruses causing outbreaks of acute gastroenteritis have been described. Among these, Aichi virus was identified in Japan in 1989. Aichi virus belongs to the Kobuvirus genus in the family Picornaviridae . This virus has been detected in outbreaks of gastroenteritis associated with oyster consumption and in pediatric stool samples, but little is known about its epidemiology or pathogenesis. In the present study, the prevalence of antibodies to Aichi virus in a Spanish population was determined between 2007 and 2008 by using an enzyme-linked immunosorbent assay (ELISA). As in previous studies, a hi…
Comparison of the immunogenicity and safety ofCervarix™ andGardasil®human papillomavirus (HPV) cervical cancer vaccines in healthy women aged 18–45 y…
2009
This observer-blind study compared the prophylactic human papillomavirus (HPV) vaccines, Cervarix (GlaxoSmithKline) and Gardasil (Merck), by assessing immunogenicity and safety through one month after completion of the three-dose vaccination course. Women (n = 1106) were stratified by age (18-26, 27-35, 36-45 years) and randomized (1:1) to receive Cervarix (Months 0, 1, 6) or Gardasil (Months 0, 2, 6). At Month 7 after first vaccination, all women in the according-to-protocol cohort who were seronegative/DNA negative before vaccination for the HPV type analyzed had seroconverted for HPV-16 and HPV-18 serum neutralizing antibodies, as measured by pseudovirion-based neutralization assay (PBNA…
Search for heavy neutral lepton production in K+ decays to positrons
2020
A search for heavy neutral lepton ($N$) production in $K^+\to e^+N$ decays using the data sample collected by the NA62 experiment at CERN in 2017--2018 is reported. Upper limits of the extended neutrino mixing matrix element $|U_{e4}|^2$ are established at the level of $10^{-9}$ over most of the accessible heavy neutral lepton mass range 144--462 MeV/$c^2$, with the assumption that the lifetime exceeds 50 ns. These limits improve significantly upon those of previous production and decay searches. The $|U_{e4}|^2$ range favoured by Big Bang Nucleosynthesis is excluded up to a mass of about 340 MeV/$c^2$.
Limits on the muon flux from neutralino annihilations at the center of the Earth with AMANDA
2006
A search has been performed for nearly vertically upgoing neutrino-induced muons with the Antarctic Muon And Neutrino Detector Array (AMANDA), using data taken over the three year period 1997–99. No excess above the expected atmospheric neutrino background has been found. Upper limits at 90% confidence level have been set on the annihilation rate of neutralinos at the center of the Earth, as well as on the muon flux at AMANDA induced by neutrinos created by the annihilation products.
Limits to the muon flux from neutralino annihilations in the Sun with the AMANDA detector
2005
A search for an excess of muon-neutrinos from neutralino annihilations in the Sun has been performed with the AMANDA-II neutrino detector using data collected in 143.7 days of live-time in 2001. No excess over the expected atmospheric neutrino background has been observed. An upper limit at 90% confidence level has been obtained on the annihilation rate of captured neutralinos in the Sun, as well as the corresponding muon flux limit at the Earth, both as functions of the neutralino mass in the range 100 GeV-5000 GeV.
Differential branching fractions and isospin asymmetries of B -> K ((*)) μ(+) μ(-) decays
2014
The isospin asymmetries of $B \to K\mu^+\mu^-$ and $B \to K^{*}\mu^+\mu^-$ decays and the partial branching fractions of the $B^0 \to K^0\mu^+\mu^-$, $B^+ \to K^+\mu^+\mu^-$ and $B^+ \to K^{*+}\mu^+\mu^-$ decays are measured as functions of the dimuon mass squared, $q^2$. The data used correspond to an integrated luminosity of 3$~$fb$^{-1}$ from proton-proton collisions collected with the LHCb detector at centre-of-mass energies of 7$\,$TeV and 8$\,$TeV in 2011 and 2012, respectively. The isospin asymmetries are both consistent with the Standard Model expectations. The three measured branching fractions, while individually consistent, all favour lower values than their respective Standard M…
Measurement of polarization amplitudes and CP asymmetries in B 0 → Φk *(892)0
2014
An angular analysis of the decay $B^0 \to \phi K^*(892)^0$ is reported based on a $pp$ collision data sample, corresponding to an integrated luminosity of 1.0 fb$^{-1}$, collected at a centre-of-mass energy of $\sqrt{s} = 7$ TeV with the LHCb detector. The P-wave amplitudes and phases are measured with a greater precision than by previous experiments, and confirm about equal amounts of longitudinal and transverse polarization. The S-wave $K^+ \pi^-$ and $K^+K^-$ contributions are taken into account and found to be significant. A comparison of the $B^0 \to \phi K^*(892)^0$ and $\bar{B}^0 \to \phi \bar{K}^*(892)^0$ results shows no evidence for direct CP violation in the rate asymmetry, in th…