1,382 research outputs found
Active immunization against virus infections due to antigenic drift by induction of crossreactive cytotoxic T lymphocytes
We have examined whether active immunization with c13 protein, a hybrid protein of the first 81 amino acids of the viral NS1 nonstructural protein and the HA2 subunit of A/PR/8 (H1N1) hemagglutinin, could protect BALB/c mice from challenge with A/PR/8 H1 subtype virus. Mice immunized with the c13 protein had a significant reduction of pulmonary virus titers with A/PR/8 (H1) virus, but failed to limit the replication of A/PC (H3) virus, which reflects the in vitro CTL activity of c13 immune spleen cells. We observed that the epitope recognized by HA2 specific CTL, which are induced by a derivative of c13 protein, is highly conserved among H1 and H2 subtype virus strains. This led us to test whether active immunization with c13 protein would also limit pulmonary virus replication in mice infected with the A/TW virus, a virus of the H1 subtype, which was isolated in 1986, and with a virus of the H2 subtype, A/Japan/305/57. Immunized mice had significantly lower lung virus titers than did control mice, and did not possess any neutralizing antibodies to the challenger viruses. These results indicate that active immunization with a fusion protein containing the cross-reactive CTL epitope protects mice from influenza infection by inducing CTL against influenza A H1 and H2 subtype virus strains, which markedly vary in their antibody binding sites on the HA1. The ability to induce active cross-reactive immunization with a fusion protein which contains a highly conserved CTL epitope offers a model for vaccine approaches against viruses which undergo significant variations in their antibody binding sites
Short-range order and precipitation in Fe-rich Fe-Cr alloys: Atomistic off-lattice Monte Carlo simulations
Short-range order (SRO) in Fe-rich Fe-Cr alloys is investigated by means of
atomistic off-lattice Monte Carlo simulations in the semi-grand canonical
ensemble using classical interatomic potentials. The SRO parameter defined by
Cowley [Phys. Rev. B 77, 669 (1950)] is used to quantify the degree of
ordering. In agreement with experiments a strong ordering tendency in the Cr
distribution at low Cr concentrations (~< 5%) is observed, as manifested in
negative values of the SRO parameters. For intermediate Cr concentrations (5%
~< c_Cr ~< 15%) the SRO parameter for the alpha-phase goes through a minimum,
but at the solubility limit the alpha-phase still displays a rather strong SRO.
In thermodynamic equilibrium for concentrations within the two-phase region the
SRO parameter measured over the entire sample therefore comprises the
contributions from both the alpha and alpha-prime phases. If both of these
contributions are taken into account, it is possible to quantitatively
reproduce the experimental results and interpret their physical implications.
It is thereby shown that the inversion of the SRO observed experimentally is
due to the formation of stable (supercritical) alpha-prime precipitates. It is
not related to the loss of SRO in the alpha-phase or to the presence of
unstable (subcritical) Cr precipitates in the alpha-phase.Comment: 9 pages, 8 figure
Ocorrência de bactérias oxidantes e redutoras de manganês em solo e rizoplano de soja com e sem encarquilhamento foliar.
Atividade microbiana e enzimática em um latossolo ácido sob doses de resíduo de reciclagem de papel.
A reciclagem de papel gera resíduos denominados lodo de Estação de Tratamento de Efluentes (ETE). Sua utilização na agricultura como corretivo de acidez do solo reduz a disposição em aterros sanitários, além de diminuir os custos de produção com calagem. O objetivo foi avaliar o efeito de diferentes doses de reciclagem de papel sobre os atributos microbiológicos de um Latossolo Ácido. O delineamento experimental foi o de blocos completos casualizados com parcelas subdivididas (com aplicação em 2004 e reaplicação em 2008). Foram conduzidos sete tratamentos constituídos de 7 doses de resíduo de reciclagem de papel: 0; 63,6; 127; 191; 254; 382; 510 t/ha e um tratamento com 10,7 t/ha de calcário dolomítico, em três repetições. O delineamento experimental foi o de blocos completos casualizados com parcelas subdivididas (com aplicação em 2004 e reaplicação em 2008). A reaplicação superficial foi de 30 t/ha do mesmo resíduo. A atividade da fosfatase ácida diminuiu com o aumento das doses de resíduo, enquanto a respiração basal aumentou. A biomassa microbiana de carbono e nitrogênio, a atividade da celulase e da desidrogenase não foram influenciadas pelos tratamentos. O principal fator que levou à alteração da atividade da fosfatase ácida e da respiração basal foi o pH do solo.Fertbio
Indicadores microbiológicos e bioquímicos de qualidade em solo de baixa fertilidade natural com diferentes manejos de calagem e adubação fosfatada.
Validation of the Japanese version of the Dementia Screening Questionnaire for Individuals with Intellectual Disabilities
Background,
Dementia in people with intellectual disabilities (IDs) is difficult to detect because of preexisting cognitive deficits. An effective screening method is required. The Dementia Screening Questionnaire for Individuals with Intellectual Disabilities (DSQIID) was developed as an observer rating tool to screen dementia in people with ID. The aim of this study was to verify the screening accuracy of the DSQIID for Japanese people with ID.
Methods
Four‐hundred ninety‐three subjects with ID participated in this study. Caregivers who had observed the participants for more than 2 years scored the Japanese version of the DSQIID (DSQIID‐J) of the participants. Three doctors examined participants directly and diagnosed dementia using the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition criteria. To identify the key screening items that predict dementia, the specificities of a single and pairs of items with 100% sensitivity were evaluated relative to the dementia diagnosis.
Results
Of 493 participants, 34 were people with Down syndrome (DS), and 459 were people without DS. Seventeen participants were diagnosed with dementia. The suitable cut‐off score of the DSQIID‐J was 10/11 (sensitivity 100% and specificity 96.8%) for screening dementia. The inter‐rater reliability, test–retest reliability and internal consistency of the DSQIID‐J were excellent. Regarding key items, there was no single item with 100% sensitivity, and the best two‐item combination was the pair of ‘Cannot dress without help’ and ‘Walks slower’ (sensitivity 100% and specificity 93.5%).
Conclusions
We identified several important question items of the DSQIID‐J related to the diagnosis of dementia in people with ID. The DSQIID‐J is a useful screening tool for dementia in adults with ID
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