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Schistosoma mansoni polypeptides immunogenic in mice vaccinated with radiation-attenuated cercariae 总被引:2,自引:0,他引:2
We compared the humoral immune response of mice protected against Schistosoma mansoni by vaccination with radiation-attenuated cercariae to that of patently infected mice, and we identified antigens that elicit a greater, or unique, immune response in the vaccinated mice. These comparisons were based upon radioimmunoprecipitations and immunodepletion of [35S]methionine-labeled schistosomular and adult worm polypeptides, followed by one- and two-dimensional polyacrylamide gel analyses. The humoral responses of patently infected mice and of mice vaccinated once were remarkably similar and were directed against schistosome glycoproteins ranging in molecular size from greater than 300 to less than 10 kDa. Exposing mice to a second vaccination resulted in a marked change in the immune response, to one predominantly directed toward high molecular size glycoproteins. Sequential immunodepletion techniques identified five schistosomular and seven adult worm antigens that showed a greater or unique immunogenicity in vaccinated mice as compared with patently infected mice. These adult worm antigens were purified by preparative sequential immunoaffinity chromatography and used to prepare a polyclonal antiserum, anti-irradiated vaccine. This antiserum bound to the surface of live newly transformed and lung-stage schistosomula, as assessed by immunofluorescence assays, and was reactive with a number of 125I-labeled schistosomular surface polypeptides, including a doublet of 150 kDa that was also recognized by sera of vaccinated mice but not by sera of patently infected mice. 相似文献
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Facial skeletal changes following hypertelorbitism correction 总被引:4,自引:0,他引:4
J B Mulliken L B Kaban C A Evans R D Strand J E Murray 《Plastic and reconstructive surgery》1986,77(1):7-16
This is a retrospective study of skeletal changes in 19 patients with corrected hypertelorism. A favorable outcome, defined as relapse less than 5 mm, occurred in patients with an average interorbital distance of 32 mm, whereas patients with an average interorbital distance of 40 mm tended to relapse over 5 mm. Neither age, interorbital configuration, nor diagnosis affected the stability of orbital translocation. At last evaluation (mean 6.7 years postoperatively), the mean interorbital distance was 22.4 mm in the favorable outcome group and 28.3 mm in the unfavorable category. This study suggested that the standard hypertelorism operation may interfere with anterior facial growth. Unless psychosocial factors predominate in a child with mild deformity, repair should be postponed until late adolescence. In a young child with gross telorbitism, nasoethmoidal resection and transmaxillary osteotomies or facial bipartition is justified. Another long-term skeletal problem was resorption of the reconstructed nasal complex. Technical and biological explanations for this are given. The correction of hypertelorism is surgery of the nose and of the midface. 相似文献
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Kerri M. Crawford Jonathan T. Bauer Liza S. Comita Maarten B. Eppinga Daniel J. Johnson Scott A. Mangan Simon A. Queenborough Allan E. Strand Katharine N. Suding James Umbanhowar James D. Bever 《Ecology letters》2019,22(8):1274-1284
Plant‐soil feedback (PSF) theory provides a powerful framework for understanding plant dynamics by integrating growth assays into predictions of whether soil communities stabilise plant–plant interactions. However, we lack a comprehensive view of the likelihood of feedback‐driven coexistence, partly because of a failure to analyse pairwise PSF, the metric directly linked to plant species coexistence. Here, we determine the relative importance of plant evolutionary history, traits, and environmental factors for coexistence through PSF using a meta‐analysis of 1038 pairwise PSF measures. Consistent with eco‐evolutionary predictions, feedback is more likely to mediate coexistence for pairs of plant species (1) associating with similar guilds of mycorrhizal fungi, (2) of increasing phylogenetic distance, and (3) interacting with native microbes. We also found evidence for a primary role of pathogens in feedback‐mediated coexistence. By combining results over several independent studies, our results confirm that PSF may play a key role in plant species coexistence, species invasion, and the phylogenetic diversification of plant communities. 相似文献
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Josef S. Smolen Ronald van Vollenhoven Arthur Kavanaugh Vibeke Strand Jiri Vencovsky Michael Schiff Robert Landewé Boulos Haraoui Catherine Arendt Irina Mountian David Carter Désirée van der Heijde 《Arthritis research & therapy》2015,17(1)
IntroductionAs patients with rheumatoid arthritis (RA) receive treatment with anti-tumour necrosis factors over several years, it is important to evaluate their long-term safety and efficacy. The objective of this study was to examine the safety and benefits of certolizumab pegol (CZP)+methotrexate (MTX) treatment for almost 5 years in patients with RA.MethodsPatients who completed the 24-week Rheumatoid Arthritis Prevention of Structural Damage (RAPID) 2 randomized controlled trial (RCT; ), or who were American College of Rheumatology (ACR) 20 non-responders at Week 16, entered the open-label extension (OLE; NCT00160602). After ≥6 months treatment with CZP 400 mg every two weeks (Q2W), dose was reduced to 200 mg Q2W, the approved maintenance dose. Safety data are presented from all patients who received ≥1 dose CZP (Safety population, n=612). Efficacy data are presented to Week 232 for the intent-to-treat (ITT, n=492) and Week 24 CZP RCT Completer (n=342) populations, and through 192 weeks of dose-reduction for the Dose-reduction population (patients whose CZP dose was reduced to 200 mg, n=369). Radiographic progression (modified total Sharp score change from RCT baseline >0.5) to Week 128 is reported for the Week 24 CZP Completers.ResultsIn the RCT, 619 patients were randomized to CZP+MTX (n=492) or placebo+MTX (n=127). Overall, 567 patients (91.6%) entered the OLE: 447 CZP and 120 placebo patients. Of all randomized patients, 358 (57.8%) were ongoing at Week 232. Annual drop-out rates during the first four years ranged from 8.4–15.0%. Event rates per 100 patient-years were 163.0 for adverse events (AEs) and 15.7 for serious AEs. Nineteen patients (3.1%) had fatal AEs (incidence rate=0.8). Clinical improvements in the RCT were maintained to Week 232 in the CZP Completers: mean Disease Activity Score 28 (Erythrocyte Sedimentation Rate) change from baseline was −3.4 and ACR20/50/70 responses 68.4%/47.1%/25.1% (non-responder imputation). Similar improvements observed in the ITT were maintained following dose-reduction. 73.2% of CZP Completers had no radiographic progression at Week 128.ConclusionsIn patients with active RA despite MTX therapy, CZP was well tolerated, with no new safety signals identified. CZP provided sustained improvements in clinical outcomes for almost 5 years. NCT00160641
Trial registration
ClinicalTrials.gov, and NCT00160602. Registered 8 September 2005. NCT00160641Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0767-2) contains supplementary material, which is available to authorized users. 相似文献8.
Ingrid Kvestad Sunita Taneja Mari Hysing Tivendra Kumar Nita Bhandari Tor A. Strand 《PloS one》2015,10(3)
Background and Objective
Infants and young children in low to middle-income countries are at risk for adverse neurodevelopment due to multiple risk factors. In this study, we sought to identify stimulation and learning opportunities, growth, and burden of respiratory infections and diarrhea as predictors for neurodevelopment.Methods
We visited 422 North Indian children 6 to 30 months old weekly for six months. Childhood illnesses were assessed biweekly. At end study, we assessed neurodevelopment using the Ages and Stages Questionnaire 3rd ed. (ASQ-3) and gathered information on stimulation and learning opportunities. We identified predictors for ASQ-3 scores in multiple linear and logistic regression models.Results
We were able to explain 30.5% of the variation in the total ASQ-3 score by the identified predictors. When adjusting for child characteristics and annual family income, stimulation and learning opportunities explained most of the variation by 25.1%. Height for age (standardized beta: 0.12, p<.05) and weight for height z-scores (std. beta: 0.09, p<.05) were positively associated with the total ASQ-3 score, while number of days with diarrhea was negatively associated with these scores (std. beta: -0.13, p<0.01).Conclusion
Our results support the importance of early child stimulation and general nutrition for child development. Our study also suggests that diarrhea is an additional risk factor for adverse neurodevelopment in vulnerable children. 相似文献9.
Marita Westhrin Minli Xie Magnus ?. Older?y Pawel Sikorski Berit L. Strand Therese Standal 《PloS one》2015,10(3)
Mineralized biomaterials are promising for use in bone tissue engineering. Culturing osteogenic cells in such materials will potentially generate biological bone grafts that may even further augment bone healing. Here, we studied osteogenic differentiation of human mesenchymal stem cells (MSC) in an alginate hydrogel system where the cells were co-immobilized with alkaline phosphatase (ALP) for gradual mineralization of the microenvironment. MSC were embedded in unmodified alginate beads and alginate beads mineralized with ALP to generate a polymer/hydroxyapatite scaffold mimicking the composition of bone. The initial scaffold mineralization induced further mineralization of the beads with nanosized particles, and scanning electron micrographs demonstrated presence of collagen in the mineralized and unmineralized alginate beads cultured in osteogenic medium. Cells in both types of beads sustained high viability and metabolic activity for the duration of the study (21 days) as evaluated by live/dead staining and alamar blue assay. MSC in beads induced to differentiate in osteogenic direction expressed higher mRNA levels of osteoblast-specific genes (RUNX2, COL1AI, SP7, BGLAP) than MSC in traditional cell cultures. Furthermore, cells differentiated in beads expressed both sclerostin (SOST) and dental matrix protein-1 (DMP1), markers for late osteoblasts/osteocytes. In conclusion, Both ALP-modified and unmodified alginate beads provide an environment that enhance osteogenic differentiation compared with traditional 2D culture. Also, the ALP-modified alginate beads showed profound mineralization and thus have the potential to serve as a bone substitute in tissue engineering. 相似文献
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