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Immunization with the pneumococcal proteins pneumolysin (Ply), choline binding protein A (CbpA), or pneumococcal surface protein A (PspA) elicits protective responses against invasive pneumococcal disease in animal models. In this study, we used different mouse models to test the efficacy of a variety of multivalent protein-based vaccines that comprised various combinations of full-length or peptide regions of the immunogens Ply, CbpA, or PspA: Ply toxoid with the L460D substitution (referred to herein as L460D); L460D fused with protective peptide epitopes from CbpA (YPT-L460D-NEEK [YLN]); L460D fused with the CD2 peptide containing the proline-rich region (PRR) of PspA (CD2-L460D); a combination of L460D and H70 (L460D+H70), a slightly larger PspA-derived peptide containing the PRR and the SM1 region; H70+YLN; and other combinations. Each mouse was immunized either intraperitoneally (i.p.) or subcutaneously (s.c.) with three doses (at 2-week intervals) of the various antigen combinations in alum adjuvant and then challenged in mouse models featuring different infection routes with multiple Streptococcus pneumoniae strains. In the i.p. infection sepsis model, H70+YLN consistently provided significant protection against three different challenge strains (serotypes 1, 2, and 6A); the CD2+YLN and H70+L460D combinations also elicited significant protection. Protection against intravenous (i.v.) sepsis (type 3 and 6A challenge strains) was largely dependent on PspA-derived antigen components, and the most protection was elicited by H70 with or without L460D or YLN. In a type 4 intratracheal (i.t.) challenge model that results in progression to meningitis, antigen combinations that contained YLN elicited the strongest protection. Thus, the trivalent antigen combination of H70+YLN elicited the strongest and broadest protection in diverse pneumococcal challenge models.  相似文献   
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The selective pressure that drives antigenic changes in influenza viruses is thought to originate from the human immune response. Here, we have characterized the B cell repertoire from a previously vaccinated donor whose serum had reduced neutralizing activity against the recently evolved clade 6B H1N1pdm09 viruses. While the response was markedly polyclonal, 88% of clones failed to recognize clade 6B viruses; however, the ability to neutralize A/USSR/90/1977 influenza, to which the donor would have been exposed in childhood, was retained. In vitro selection of virus variants with representative monoclonal antibodies revealed that a single amino acid replacement at residue K163 in the Sa antigenic site, which is characteristic of the clade 6B viruses, was responsible for resistance to neutralization by multiple monoclonal antibodies and the donor serum. The K163 residue lies in a part of a conserved surface that is common to the hemagglutinins of the 1977 and 2009 H1N1 viruses. Vaccination with the 2009 hemagglutinin induced an antibody response tightly focused on this common surface that is capable of selecting current antigenic drift variants in H1N1pdm09 influenza viruses. Moreover, amino acid replacement at K163 was not highlighted by standard ferret antisera. Human monoclonal antibodies may be a useful adjunct to ferret antisera for detecting antigenic drift in influenza viruses.  相似文献   
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OBJECTIVE

Limited information exists about the influence of urologic complications on health-related quality of life (HRQOL) in patients with type 1 diabetes.

RESEARCH DESIGN AND METHODS

We studied 664 men and 580 women from the Diabetes Control and Complications Trial/Epidemiology of Interventions and Complications Study: mean ages were 51.6 ± 6.6 and 50.6 ± 7.2 years and duration of diabetes was 29.5 ± 4.8 and 29.8 ± 5.1 years, respectively. We assessed associations of sexual dysfunction, lower urinary tract symptoms (LUTS), and, in women, urinary incontinence (UI) with general quality of life (SF-36), perceived value of health (EuroQol-5), diabetes-related quality of life (Diabetes Quality of Life Scale [DQOL]), and psychiatric symptoms (Symptom Checklist 90-R).

RESULTS

In both men and women, urologic complications adversely affected HRQOL and psychiatric symptoms, even after accounting for history of depression leading to treatment. Multivariable analyses accounting for the presence of diabetic retinopathy, neuropathy, and nephropathy also revealed substantial independent effects. In men, for example, the odds (95% CI) of a low DQOL score (≤25th percentile) were 3.01 (1.90–4.75) times greater with erectile dysfunction and 2.65 (1.68–4.18) times greater with LUTS and in women, 2.04 (1.25–3.35) times greater with sexual dysfunction and 2.71 (1.72–4.27) times greater with UI/LUTS combined compared with men and women without such complications. Similar effects were observed for the other measures.

CONCLUSIONS

Sexual dysfunction and urinary complications with type 1 diabetes are associated with decreased quality of life and perceived value of health and with higher levels of psychiatric symptoms, even after accounting for other diabetes complications and depression treatment.  相似文献   
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Stage models have largely informed scholarship on supervisor developmental processes. We argue that understanding this development as occurring along dimensions is more useful for both supervision practitioners and educators as well as for those engaged in research on supervisor development. Building on the work of Heid ( 1997 ) and working with a panel of 7 supervision experts, we identify 10 themes and validate their salience to supervisor development using a sample of 22 clinical supervisors. We describe and elaborate on each theme, and then present and discuss a case vignette that illustrates many of the supervisor developmental themes.  相似文献   
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