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41.
The persistence of antigen-specific memory B-cells (MBCs) in children and young adults long time after vaccination against measles, mumps and rubella (MMR) is not known. Here we have looked at the Swedish immunization program and examined children 1–10 years after the first MMR dose in early childhood, as well as young adults 7–18 years after the second dose of MMR. We show that Ab titers and MBCs against measles and rubella have different kinetics, indicating that the MBC pool and the corresponding Ab titers are regulated independently. These data fit well with other findings that continuous IgG secretion comes from long-lived plasma cells and not MBCs. We also demonstrate that individuals with low post-vaccination Ab titers might have an adequate MBC response. It remains to be shown if memory B-cells provide the same protection as specific antibodies, but our data is a valuable complement to the incomplete knowledge about correlates of protection after vaccination.  相似文献   
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Most health-related literature is written above the reading ability of the lay audience; however, no studies to date have identified the impact of medical terms on readability of health education materials. The purpose of this study was to identify whether there was a change in calculated reading levels of patient education brochures after medical terms were removed from analysis passages. The reading levels of 5 patient education brochures were analyzed before and after removal of medical terms, using both the Fry and Simple Measure of Gobbledegook (SMOG) readability formulas. Results indicated that the reading levels for all brochures were significantly lower after removal of medical terminology, but they remained above the 5th to 6h grade level recommended by health education experts. Findings hold implications for healthcare professionals in relation to the development and evaluation of patient education materials.  相似文献   
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As part of a larger study, this article describes the local authorities in Norway as providers of help and survivors as recipients of help after the suicide of a young person ( < 30 years) in 83 families. A questionnaire developed for this study maps the extent of professional community support as reported by parent survivors (N = 128).Additionally, 41survivors described the quality of the assistance through in-depth interviews. Another questionnaire assesses the provisions and the organization of intervention strategies in local communities. Personnel in 321of Norway's481municipalities responded. Although survivors'wishes for ideal support coincide with recommendations by experts in the field, local authorities lack the organization to fulfill such expectations.The discussion highlights issues relating to content, organization, and ideology of the assistance.  相似文献   
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Angiopoietin-1 promotes LYVE-1-positive lymphatic vessel formation   总被引:20,自引:3,他引:20       下载免费PDF全文
Angiopoietin (Ang) signaling plays a role in angiogenesis and remodeling of blood vessels through the receptor tyrosine kinase Tie2, which is expressed on blood vessel endothelial cells (BECs). Recently it has been shown that Ang-2 is crucial for the formation of lymphatic vasculature and that defects in lymphangiogenesis seen in Ang-2 mutant mice are rescued by Ang-1. These findings suggest important roles for Ang signaling in the lymphatic vessel system; however, Ang function in lymphangiogenesis has not been characterized. In this study, we reveal that lymphatic vascular endothelial hyaluronan receptor 1-positive (LYVE-1(+)) lymphatic endothelial cells (LECs) express Tie2 in both embryonic and adult settings, indicating that Ang signaling occurs in lymphatic vessels. Therefore, we examined whether Ang-1 acts on in vivo lymphatic angiogenesis and in vitro growth of LECs. A chimeric form of Ang-1, cartilage oligomeric matrix protein (COMP)-Ang-1, promotes in vivo lymphatic angiogenesis in mouse cornea. Moreover, we found that COMP-Ang-1 stimulates in vitro colony formation of LECs. These Ang-1-induced in vivo and in vitro effects on LECs were suppressed by soluble Tie2-Fc fusion protein, which acts as an inhibitor by sequestering Ang-1. On the basis of these observations, we propose that Ang signaling regulates lymphatic vessel formation through Tie2.  相似文献   
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The aim of this retrospective observational study was to evaluate age, length of hospital stay and development of complications in children hospitalized with community- or nosocomially- acquired rotavirus gastroenteritis (RV GE). In total, medical records of 984 children with RV GE were analysed retrospectively. The median age was 13.8 months (3 weeks to 99 months) in children with community acquired RV GE (n=723) and 9.0 months (range 3 weeks to 82 months) in children with nosocomially acquired RV GE (n=261). During this 11-y surveillance, only 2 children were admitted twice for a RV GE, suggesting development of subsequent protective immunity against severe rotavirus gastroenteritis after the first episode. Complications occurred in 16.5% of the children with community acquired RV GE and only in 1.9% of the nosocomially acquired RV GE. Identified complications in children with community acquired RV GE were: severe dehydration resulting in intensive care (1.7%), death (0.1%), hypertonic dehydration (9.1%), seizures (4.0%) and encephalitis with abnormal EEG (1.7%). The median age of children in need of intensive care was 9.1 months and in those developing hypertonic dehydration 10.8 months, both significantly lower than in children with no complications (p<0.05). Interestingly, the age of children developing seizures and signs of encephalitis was significantly higher than in children with no complications (p<0.01).  相似文献   
47.
Social exploitation of vitellogenin   总被引:13,自引:0,他引:13       下载免费PDF全文
Vitellogenin is a female-specific glucolipoprotein yolk precursor produced by all oviparous animals. Vitellogenin expression is under hormonal control, and the protein is generally synthesized directly before yolk deposition. In the honeybee (Apis mellifera), vitellogenin is not only synthesized by the reproductive queen, but also by the functionally sterile workers. In summer, the worker population consists of a hive bee group performing a multitude of tasks including nursing inside the nest, and a forager group specialized in collecting nectar, pollen, water, and propolis. Vitellogenin is synthesized in large quantities by hive bees. When hive bees develop into foragers, their juvenile hormone titers increase, and this causes cessation of their vitellogenin production. This inverse relationship between vitellogenin synthesis and juvenile hormone is opposite to the norm in insects, and the underlying proximate processes and life-history reasons are still not understood. Here we document an alternative use of vitellogenin by showing that it is a source for the proteinaceous royal jelly that is produced by the hive bees. Hive bees use the jelly to feed larvae, queen, workers, and drones. This finding suggests that the evolution of a brood-rearing worker class and a specialized forager class in an advanced eusocial insect society has been directed by an alternative utilization of yolk protein.  相似文献   
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