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11.
Intranasally administered influenza vaccines could be more effective than injected vaccines, because intranasal vaccination can induce virus-specific immunoglobulin A (IgA) antibodies in the upper respiratory tract, which is the initial site of infection. In this study, immune responses elicited by an intranasal inactivated vaccine of influenza A(H5N1) virus were evaluated in healthy individuals naive for influenza A(H5N1) virus. Three doses of intranasal inactivated whole-virion H5 influenza vaccine induced strong neutralizing nasal IgA and serum IgG antibodies. In addition, a mucoadhesive excipient, carboxy vinyl polymer, had a notable impact on the induction of nasal IgA antibody responses but not on serum IgG antibody responses. The nasal hemagglutinin (HA)-specific IgA antibody responses clearly correlated with mucosal neutralizing antibody responses, indicating that measurement of nasal HA-specific IgA titers could be used as a surrogate for the mucosal antibody response. Furthermore, increased numbers of plasma cells and vaccine antigen-specific Th cells in the peripheral blood were observed after vaccination, suggesting that peripheral blood biomarkers may also be used to evaluate the intranasal vaccine-induced immune response. However, peripheral blood immune cell responses correlated with neutralizing antibody titers in serum samples but not in nasal wash samples. Thus, analysis of the peripheral blood immune response could be a surrogate for the systemic immune response to intranasal vaccination but not for the mucosal immune response. The current study suggests the clinical potential of intranasal inactivated vaccines against influenza A(H5N1) viruses and highlights the need to develop novel means to evaluate intranasal vaccine-induced mucosal immune responses.  相似文献   
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Using acoustic telemetry methods on large numbers of tagged fish, we studied how the holding behavior of Chinook salmon and steelhead smolts could be related to habitat features and spatial and temporal variables on a highly altered section of the Sacramento River. We viewed downstream migration as a process in which fish transition between moving and holding states, and used a binomial and negative binomial Generalized Linear Model to analyze two aspects of holding: 1) probability of holding, and 2) holding time. For Chinook salmon, the probability of holding increased as wood size and fine substrates increased; holding time increased as overhead shade increased. For steelhead, holding behavior was only weakly related to habitat variables, in contrast to the strong relationships with spatial and temporal variables. For both species, the probability of holding increased when distance from the release location decreased and instream flows decreased. We found support for three main findings: 1) spatial and temporal factors have considerably greater influence on Chinook salmon and steelhead smolt holding behavior than nearshore habitat features; 2) holding behaviors of Chinook salmon smolts are influenced more strongly by habitat features than steelhead smolts; and 3) incorporation of habitat features such as large woody material and overhead shade should be considered when conducting nearshore bank rehabilitation projects to increase cover from predators and provide velocity refuge, improving holding habitat during downstream migration.  相似文献   
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Heavily glycosylated mucin glycopeptides such as CA 27.29 and CA 15–3 are currently being used as biomarkers for detection and monitoring of breast cancer. However, they are not well detected at the early stages of the cancer. In the present study, perchloric acid (PCA) was used to enhance detection of mucin-type O-glycosylated proteins in the serum in an attempt to identify new biomarkers for early stage breast cancer. Sensitivity and specificity of an earlier developed sandwich enzyme-linked lectin assay were significantly improved with the use of serum PCA isolates. When a pilot case-control study was performed using the serum PCA isolates of normal participants (n = 105) and patients with stage 0 (n = 31) and stage I (n = 48) breast cancer, higher levels of total O-glycosylated proteins in sera of both groups of early stage breast cancer patients compared to the normal control women were demonstrated. Further analysis by gel-based proteomics detected significant inverse altered abundance of proteoglycan 4 and plasma protease C1 inhibitor in both the early stages of breast cancer patients compared to the controls. Our data suggests that the ratio of serum proteoglycan 4 to protease C1 inhibitor may be used for screening of early breast cancer although this requires further validation in clinically representative populations.  相似文献   
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In this report, a novel D-shaped long-range surface plasmon resonance (LRSPR) fiber base sensor has been introduced. The demonstration of proposed sensor involves two D-shaped silver-coated models to study the sensitivity responses. The entire study with the constructed models is based on a single-mode fiber. The models are multilayered consisting of metal, dielectric, and analyte as separate layers. Silver (Ag) and magnesium fluoride (MgF2) strips are used as metal and dielectric layers respectively. The constituency of analyte as an interface excellently standardized the models for sensitivity detection. In this report, a large range of analyte refractive indices (RI) which varies from 1.33 to 1.38 is appraised for the proposed models to characterize the sensitivity. The entire context is encompassed by the wavelength region from 450 to 850 nm with an interval of 20 nm. Sensitivities in this report are measured based on the analyte position from the core and metal for both models. For each of the two models, the analyte is placed as the top layer. RIs of the applied metal (Ag) are measured using the Drude-Lorentz formula. The simulated sensitivities for model-1 and model-2 vary from 6.3?×?103 nm/RIU to 8.7?×?103 nm/RIU.

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To clarify consistency in the size of carbon pool of a lowland tropical rainforest, we calculated changes in above-ground biomass in the Pasoh Forest Reserve, Peninsular Malaysia. We estimated the total above-ground biomass of a mature stand using tree census data obtained in a 6-ha plot every 2years from 1994 to 1998. The total above-ground biomass decreased consistently from 1994 (431Mgha–1) to 1998 (403Mgha–1) (1Mg=103 kg). These are much lower than that in 1973 for a 0.2ha portion of the same area, suggesting that the the total above-ground biomass reduction might have been consistent in recent decades. This trend contrasted with a major trend for neotropical forests. During 1994–1998, the forest gained 23.0 and 0.88Mgha–1 of the total above-ground biomass by tree growth and recruitment, respectively, and lost 51.9Mgha–1 by mortality. Overall, the biomass decreased by 28.4Mgha–1 (i.e. 7.10Mgha–1·year–1), which is almost equivalent to losing a 76-cm-diameter living tree per hectare per year. Analysis of positive and negative components of biomass change revealed that deaths of large trees dominated the total above-ground biomass decrease. The forest biomass also varied spatially, with the total above-ground biomass density ranging 212–655Mgha–1 on a 0.2-ha basis (n= 30 subplots, 1998) and 365–440Mgha–1 on a 1ha basis. A large decrease of the total above-ground biomass density (>50Mg per ha per 2years) in several 0.2-ha subplots contributed to the overall decrease in the 6-ha total above-ground biomass. In the present study, we discuss the association between forest dynamics and biomass fluctuation, and the implication for carbon cycling in mature forests with emphasis on forest monitoring and assessments of soil and decomposition systems.  相似文献   
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