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991.
Proteins with molecular masses of 25 to 40 kilodaltons elicit optimal protective responses against Plasmodium chabaudi adami infection. 下载免费PDF全文
The presence of the CD4+ T cell has been shown to be crucial for resolution of acute infection in the Plasmodium chabaudi adami murine malaria model. This model is, therefore, suitable for the isolation of malaria antigens that are capable of activating protective T cells. In light of this, we set out to identify P. chabaudi adami molecules that activate protective responses in this model. Denatured P. chabaudi adami proteins were isolated by continuous-flow electrophoresis on the basis of their apparent molecular masses and then sequentially assessed for the ability to protect mice in immunization experiments. We report here that low-molecular-mass P. chabaudi adami polypeptides in the range from 25 to 40 kDa are most effective at immunizing mice against a challenge infection with viable P. chabaudi adami. The method used to obtain these proteins could also be applied to identify molecules that activate protective cell-mediated responses in other infectious disease models. 相似文献
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Soluble Fas and soluble Fas ligand proteins in human milk: possible significance in the development of immunological tolerance 总被引:4,自引:0,他引:4
Human milk contains a complex uncharacterized, immune system able to exert actions both locally and systemically. This study reports the results of an ELISA-based quantitation of soluble Fas and soluble Fas ligand in human milk which may modulate the Fas/FasL system that is critical for the expression of immune tolerance and apoptosis. Production of Fas/FasL mRNAs by milk cells was also examined using RT-PCR. Fas is ubiquitously expressed in various cells and when bound by its ligand FasL, present predominantly on activated T- and NK cells, Fas-expressing cells are killed. A large amount of soluble Fas (1746-4320 pg/ml) is detected in colostrum, transitional milk and the mature milk of mothers delivering prematurely or at full-term, whereas FasL is present only in the range 123-310 pg/ml. Milk cells are positive for Fas mRNA, but negative for FasL mRNA. An excess of soluble Fas in human milk may bind to FasL preventing apoptosis and preserving epithelial barriers, and may represent an additional new mechanism whereby human milk favours immune tolerance and normal gastrointestinal development. 相似文献
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Hiten D. Patel Arnav Srivastava Ridwan Alam Gregory A. Joice Zeyad R. Schwen Alice Semerjian Mohamad E. Allaf Phillip M. Pierorazio 《Urologic oncology》2017,35(10):606.e1-606.e7
Introduction
Testicular seminoma affects relatively young men with excellent survival outcomes. There has been increasing concern that radiotherapy (RT) leads to secondary malignant neoplasms (SMNs) and subsequent mortality. We evaluated the effect of RT on incidence of SMNs and quantified cancer-related mortality and other causes of death for patients with stage I and II testicular seminoma.Material and methods
A national sample of men (1988–2013) diagnosed with stage IA/IB/IS/IIA/IIB/IIC testicular seminomas from Surveillance, Epidemiology, and End Results were evaluated. Use of RT over time and survival curves (5/10/15-year) was stratified by stage. Log-binomial regression determined relative risk of developing SMNs. Incidence rate ratios (IRR) and age-adjusted Cox proportional hazards models compared overall, cancer-specific survival (CSS), and other cancer-specific survival. Competing-risks regression generated cumulative incidence functions. Prevalence ratios explored excess deaths owing to specific causes.Results
A total of 16,463 men were included with 9,126 (55.4%) undergoing RT with markedly decreased use for stage I seminoma in recent years (<20%) and ~50% for stage IIA. RT increased risk of SMNs (relative risk = 1.84 [95% CI: 1.61–2.10, P<0.01]). Survival rates were excellent (15-year CSS for stage I [≥99%], stage IIA [98.1%], stage IIB-C [96%–97%]). RT was associated with improved CSS for stage IB and IIA, but demonstrated less benefit for stage IA (IRR = 0.63 [95% CI: 0.35–1.14, P = 0.10]) with worse other cancer-specific survival (IRR = 1.80 [95% CI: 0.97–3.59, P = 0.05]). Gastrointestinal, respiratory, urinary, and hematologic malignances accounted for 84% of SMN deaths.Conclusions
RT offers excellent CSS for men with stage I/II seminoma and an increased risk of SMN later in life. Future studies should better evaluate risk-stratification for stage IB patients. 相似文献997.
This study uses data from the 2004–2006 Australian National Survey of Adult Oral Health and a simultaneous equation framework to investigate the interrelationships between dental health, private dental insurance and the use of dental services. The results show that insurance participation is influenced by social and demographic factors, health and health behaviours. In turn, these factors affect the use of dental services, both directly and through insurance participation. Our findings confirm that affordability is a major barrier to visiting the dentist for oral health maintenance and treatment. Our results suggest that having supplementary insurance is associated with some 56 percentage points higher probability of seeing the dentist in the general population. For those who did not have private insurance cover, we predict that conditional on them facing the same insurance conditions, on average, having insurance would increase their visits to the dentist by 43 percentage points. The uninsured in the survey have lower income, worse oral health and lower rates of preventive and treatment visits. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Sundeep?Singh?SalujaEmail author Vaibhav?Kumar?Varshney Pramod?Kumar?Mishra Siddharth?Srivastava Ravi?Meher Pritul?Saxena 《World journal of surgery》2017,41(8):2053-2061