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81.
Kent A. Smith Victor L. Tam Raymond M. Wong Robb R. Pagarigan Brenna L. Meisenburg Diljeet K. Joea Xiping Liu Christiana Sanders David Diamond Thomas M. Kündig Zhiyong Qiu Adrian Bot 《Vaccine》2009
DNA vaccines or peptides are capable of inducing specific immunity; however, their translation to the clinic has generally been problematic, primarily due to the reduced magnitude of immune response and poor pharmacokinetics. Herein, we demonstrate that a novel immunization strategy, encompassing sequential exposure of the lymph node milieu to plasmid and peptide in a heterologous prime-boost fashion, results in considerable MHC class I-restricted immunity in mice. Plasmid-primed antigen expression was essential for the generation of a population of central memory T cells, expressing CD62L and low in PD-1, with substantial capability to expand and differentiate to peripheral memory and effector cells, following subsequent exposure to peptide. These vaccine-induced T cells dominated the T cell repertoire, were able to produce large amounts of chemokines and pro-inflammatory cytokines, and recognized tumor cells effectively. In addition to outlining a feasible and effective method to transform plasmid DNA vaccination into a potentially viable immunotherapeutic approach for cancer, this study sheds light on the mechanism of heterologous prime-boost and the considerable heterogeneity of MHC class I-restricted T cell responses. 相似文献
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Grootscholten C Bajema IM Florquin S Steenbergen EJ Peutz-Kootstra CJ Goldschmeding R Bijl M Hagen EC Van Houwelingen HC Derksen RH Berden JH;Dutch Working Party on Systemic Lupus Erythematosus 《Arthritis and rheumatism》2007,56(3):924-937
OBJECTIVE: To analyze the effect of treatment with either pulse cyclophosphamide (CYC) or azathioprine (AZA) combined with methylprednisolone (MP), on serial biopsy results in patients with proliferative lupus nephritis, and to evaluate the predictive value of various histopathologic and clinical parameters with regard to disease outcome. METHODS: Biopsy specimens from patients with proliferative lupus nephritis, obtained at study entry and after 2 years of therapy, were scored according to a standardized method, and results assessed in relation to disease outcome. RESULTS: Of the 87 patients originally enrolled, 39 underwent repeat biopsy. These patients were representative of the overall group, both at entry and at 2-year followup. The median activity index changed from 8.0 to 2.7 (no differences between the treatment groups). In the group treated with AZA plus MP (AZA group), the increase in the median chronicity index (from 2.7 to 3.8) was larger than that in the CYC group (from 2.7 to 3.0) (P = 0.050). In multivariate analyses, renal function at enrollment and after 2 years was the best predictor of renal function at the last visit, while none of the histopathologic variables (either at entry or at 2 years) added to this prediction. Comparing patients whose disease transitioned to class II with those who had persistent proliferative lupus nephritis revealed no differences between the treatment groups at either time point, and no clinical differences at 2 years. However, a higher serum creatinine level at entry and greater proteinuria at last visit were characteristic of patients who still had proliferative lupus nephritis at 2 years. CONCLUSION: These results indicate that, although both CYC and AZA are effective in reducing active lesions in lupus nephritis, progression of chronic lesions is more effectively halted by CYC. Variables assessed by repeat biopsy do not predict clinical outcome. 相似文献
84.
Grootscholten C Dieker JW McGrath FD Roos A Derksen RH van der Vlag J Daha MR Berden JH 《Annals of the rheumatic diseases》2007,66(5):693-696
OBJECTIVE: To study the prevalence and course of anti-chromatin (anti-nucleosome, anti-double-stranded (ds) DNA and anti-histone) and anti-C1q autoantibodies in patients with proliferative lupus nephritis (LN), treated in a randomised controlled trial with either cyclophosphamide or azathioprine plus methylprednisolone. METHODS: Autoantibody levels were measured and analysed in 52 patients with proliferative LN, during their first year of treatment. Levels in both treatment arms were compared and associations with clinical, serological and outcome parameters were studied. RESULTS: At study entry, prevalences for anti-nucleosome, anti-dsDNA, anti-histone and anti-C1q autoantibodies were 81%, 96%, 23% and 65%, respectively. Anti-chromatin autoantibodies correlated with each other, but not with anti-C1q levels. If patients were divided for their autoantibody titre at the start of treatment above or below the median, the only significant differences were higher SLE disease activity index with higher anti-nucleosome, and higher creatinine with higher anti-C1q autoantibodies. During the first year, a comparable rapid decline in the levels of anti-nucleosome, anti-dsDNA and anti-C1q autoantibodies was seen in both treatment arms. Anti-histone autoantibody levels were low and did not change. Renal flares were not preceded by rises in autoantibody titres. CONCLUSIONS: These results indicate that measurement of anti-chromatin and anti-C1q autoantibodies is useful for diagnosing LN, but not for monitoring disease course. 相似文献
85.
beta2-Glycoprotein I inhibits von Willebrand factor dependent platelet adhesion and aggregation 总被引:3,自引:0,他引:3 下载免费PDF全文
Patients with antiphospholipid syndrome are characterized by the association of thrombosis or pregnancy morbidity and the presence of antiphospholipid autoantibodies. Particularly, anti-beta(2)-glycoprotein (beta(2) GPI) autoantibodies correlate with thrombosis, suggesting an antibody-induced gain of prothrombotic function and/or an antibody-induced loss of antithrombotic function of beta(2) GPI. In the search for potential antithrombotic properties of beta(2) GPI, we found that beta(2) GPI inhibits von Willebrand factor (VWF)-induced platelet aggregation. In addition, platelet adhesion to a VWF-coated surface was decreased by 50% in the presence of beta(2) GPI (P < .03). beta(2) GPI binds to the A1 domain of VWF but preferably when the A1 domain is in its active glycoprotein Ibalpha-binding conformation. Anti-beta(2) GPI antibodies isolated from a subset of antiphospholipid syndrome patients neutralized the beta(2) GPI-VWF interactions and thus the inhibitory activity of beta(2) GPI. In comparison to healthy individuals, the amounts of active VWF in circulation were increased 1.5-fold (P < .001) in patients positive for lupus anticoagulant (LAC) due to anti-beta(2) GPI antibodies. Thus, beta(2) GPI is a biologically relevant inhibitor of VWF function by interfering with VWF-dependent platelet adhesion. Anti-beta(2) GPI autoantibodies neutralize this inhibitory function and are associated with increased levels of active VWF. This mode of action could contribute to the thrombosis and consumptive thrombocytopenia observed in patients with anti-beta(2) GPI antibodies. 相似文献
86.
Gignoux CR Henn BM Mountain JL 《Proceedings of the National Academy of Sciences of the United States of America》2011,108(15):6044-6049
The invention of agriculture is widely assumed to have driven recent human population growth. However, direct genetic evidence for population growth after independent agricultural origins has been elusive. We estimated population sizes through time from a set of globally distributed whole mitochondrial genomes, after separating lineages associated with agricultural populations from those associated with hunter-gatherers. The coalescent-based analysis revealed strong evidence for distinct demographic expansions in Europe, southeastern Asia, and sub-Saharan Africa within the past 10,000 y. Estimates of the timing of population growth based on genetic data correspond neatly to dates for the initial origins of agriculture derived from archaeological evidence. Comparisons of rates of population growth through time reveal that the invention of agriculture facilitated a fivefold increase in population growth relative to more ancient expansions of hunter-gatherers. 相似文献
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88.
Jacques Chiaroni Roy J King Natalie M Myres Brenna M Henn Axel Ducourneau Michael J Mitchell Gilles Boetsch Issa Sheikha Alice A Lin Mahnoosh Nik-Ahd Jabeen Ahmad Francesca Lattanzi Rene J Herrera Muntaser E Ibrahim Aaron Brody Ornella Semino Toomas Kivisild Peter A Underhill 《European journal of human genetics : EJHG》2010,18(3):348-353
Haplogroup J1 is a prevalent Y-chromosome lineage within the Near East. We report the frequency and YSTR diversity data for its major sub-clade (J1e). The overall expansion time estimated from 453 chromosomes is 10 000 years. Moreover, the previously described J1 (DYS388=13) chromosomes, frequently found in the Caucasus and eastern Anatolian populations, were ancestral to J1e and displayed an expansion time of 9000 years. For J1e, the Zagros/Taurus mountain region displays the highest haplotype diversity, although the J1e frequency increases toward the peripheral Arabian Peninsula. The southerly pattern of decreasing expansion time estimates is consistent with the serial drift and founder effect processes. The first such migration is predicted to have occurred at the onset of the Neolithic, and accordingly J1e parallels the establishment of rain-fed agriculture and semi-nomadic herders throughout the Fertile Crescent. Subsequently, J1e lineages might have been involved in episodes of the expansion of pastoralists into arid habitats coinciding with the spread of Arabic and other Semitic-speaking populations. 相似文献
89.
Michael Matthew Francis Tom A. Hummer Jenifer L. Vohs Matthew G. Yung Emily Liffick Nicole F. Mehdiyoun Alexander J. Radnovich Brenna C. McDonald Andrew J. Saykin Alan Breier 《Brain imaging and behavior》2016,10(1):1-11
Studies have demonstrated that episodic memory (EM) is often preferentially disrupted in schizophrenia. The neural substrates that mediate EM impairment in this illness are not fully understood. Several functional magnetic resonance imaging (fMRI) studies have employed EM probe tasks to elucidate the neural underpinnings of impairment, though results have been inconsistent. The majority of EM imaging studies have been conducted in chronic forms of schizophrenia with relatively few studies in early phase patients. Early phase schizophrenia studies are important because they may provide information regarding when EM deficits occur and address potential confounds more frequently observed in chronic populations. In this study, we assessed brain activation during the performance of visual scene encoding and recognition fMRI tasks in patients with earlyphase psychosis (n?=?35) and age, sex, and race matched healthy control subjects (n?=?20). Patients demonstrated significantly lower activation than controls in the right hippocampus and left fusiform gyrus during scene encoding and lower activation in the posterior cingulate, precuneus, and left middle temporal cortex during recognition of target scenes. Symptom levels were not related to the imaging findings, though better cognitive performance in patients was associated with greater right hippocampal activation during encoding. These results provide evidence of altered function in neuroanatomical circuitry subserving EM early in the course of psychotic illness, which may have implications for pathophysiological models of this illness. 相似文献
90.
Elenka Brenna 《Health policy (Amsterdam, Netherlands)》2021,125(3):415-423
Setting and objectiveIn Italy, over the last decades, elderly care has been mostly provided by family members, especially adult offspring, and in particular daughters. This paper investigates the relationship between informal caregiving and mental distress among Italians aged 35–59, with a focus on gender effect and parenthood responsibilities.DataThe dataset is the European Health Interview Survey (EHIS), second wave, year 2015. As far as it is known, the Italian EHIS has not been used for studies on ageing and caregiving.MethodsUsing selected subsamples, a Propensity Score Matching between caregivers and non-caregivers aged 35–59 is implemented, with the aim of measuring the difference in level of depression, if any, between the two groups.ResultsFindings show that women providing their frail relatives with informal care are less likely to suffer from mental distress compared to non-carers. However, results change radically if they have children aged less than 15 at home, and a higher probability of being depressed is detected for women overwhelmed by the double responsibility of assisting both dependent relatives and their own children. Results are not significant for men. 相似文献