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131.
Kathleen Y. Wolin Dori M. Steinberg Ilana B. Lane Sandy Askew Mary L. Greaney Graham A. Colditz Gary G. Bennett 《PloS one》2015,10(10)
Background
While eHealth approaches hold promise for improving the reach and cost-effectiveness of behavior change interventions, they have been challenged by declining participant engagement over time, particularly for self-monitoring behaviors. These are significant concerns in the context of chronic disease prevention and management where durable effects are important for driving meaningful changes.Purpose
“Be Fit, Be Well” was an eHealth weight loss intervention that allowed participants to self-select a self-monitoring modality (web or interactive voice response (IVR)). Participants could change their modality. As such, this study provides a unique opportunity to examine the effects of intervention modality choice and changing modalities on intervention engagement and outcomes.Methods
Intervention participants, who were recruited from community health centers, (n = 180) were expected to self-monitor health behaviors weekly over the course of the 24-month intervention. We examined trends in intervention engagement by modality (web, IVR, or changed modality) among participants in the intervention arm.Results
The majority (61%) of participants chose IVR self-monitoring, while 39% chose web. 56% of those who selected web monitoring changed to IVR during the study versus no change in those who initially selected IVR. Self-monitoring declined in both modalities, but completion rates were higher in those who selected IVR. There were no associations between self-monitoring modality and weight or blood pressure outcomes.Conclusions
This is the first study to compare web and IVR self-monitoring in an eHealth intervention where participants could select and change their self-monitoring modality. IVR shows promise for achieving consistent engagement. 相似文献132.
Luisa Campagnolo Gaetana Costanza Arianna Francesconi Gaetano Arcuri Ilana Moscatelli Augusto Orlandi 《PloS one》2014,9(1)
Background
Sortilin, a member of the Vps10p-domain receptor family, has been demonstrated a key regulator in mediating cellular response to pro-neurotrophins. In the present study, we investigated the role of sortilin in the apoptotic pathway of vascular smooth muscle cells.Methods and Principal Findings
Immunohistochemistry revealed that sortilin was barely detectable in human and rat normal young vessels, while its expression was increased in human fibroatheromatous plaques. Sortilin immunodetection was also marked in the neointima of the rat aorta fifteen days after ballooning. In vitro, rat aortic intimal cells expressed higher sortilin levels than normal media SMCs; sortilin was distributed in the cytoplasm and in correspondence of the cell membrane. After 48 h, pro-nerve growth factor (proNGF) induced the strong dose-dependent increase of intimal cell apoptosis and the accumulation of sortilin protein. ProNGF was a more potent apoptotic inducer than equimolar or even higher concentration of NGF, whereas brain derived neutrotrophic factor was ineffective. Targeted interfering RNA-mediated sortilin reduction counteracted proNGF-induced apoptosis without affecting p75NTR expression. ProNGF-induced apoptosis was associated to NF-κB down-regulation and bax increase. Inhibition of NF-κB activity increased intimal cell apoptosis that did not further increase with the addition of proNGF.Conclusions
Our results indicate that sortilin expression characterizes human atheromatous lesions and rat aortic post-injury neointima, and suggest that sortilin represents an important regulator of proNGF-induced SMC apoptosis and arterial remodeling. 相似文献133.
Roger A. Johnson Ilana Shoshani Carmen Dessauer Gilles Gosselin 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):839-842
Abstract An enzymatic method was developed for the preparation of unlabeled and [β-32P]-labeled β-L-2′,3′-dd-5′ATP from the monophosphate with near quantitative yields. β-L-2′,3′-dd-5′ATP was a competitive and potent inhibitor of adenylyl cyclases (IC5 ~ 30 nM). Upon uvirradiation β-L-2′,3′-dd-[β-32P]-5′ATP directly crosslinked to a chimeric construct of this enzyme. Data suggest that this is a pre-transition state inhibitor and contrasts with the equipotent 2′,5′-dd-3′ATP, a post-transition state, noncompetitive inhibitor. 相似文献
134.
Jarad M. Schiffer Panagiotis Maniatis Ilana Garza Evelene Steward-Clark Lawrence T. Korman Phillip R. Pittman Joanne V. Mei Conrad P. Quinn 《Biologicals》2013,41(2):98-103
The collection, processing and transportation to a testing laboratory of large numbers of clinical samples during an emergency response situation present significant cost and logistical issues. Blood and serum are common clinical samples for diagnosis of disease. Serum preparation requires significant on-site equipment and facilities for immediate processing and cold storage, and significant costs for cold-chain transport to testing facilities. The dried blood spot (DBS) matrix offers an alternative to serum for rapid and efficient sample collection with fewer on-site equipment requirements and considerably lower storage and transport costs. We have developed and validated assay methods for using DBS in the quantitative anti-protective antigen IgG enzyme-linked immunosorbent assay (ELISA), one of the primary assays for assessing immunogenicity of anthrax vaccine and for confirmatory diagnosis of Bacillus anthracis infection in humans. We have also developed and validated high-throughput data analysis software to facilitate data handling for large clinical trials and emergency response. 相似文献
135.
136.
Ilana Chefetz Jennie C Holmberg Ayesha B Alvero Irene Visintin Gil Mor 《Cell cycle (Georgetown, Tex.)》2011,10(13):2206-2214
Recurrent ovarian cancer is resistant to conventional chemotherapy. A sub-population of ovarian cancer cells, the epithelial ovarian cancer stem cells (EOC stem cells) have stemness properties, constitutive NFκB activity, and represent the chemoresistant population. Currently, there is no effective treatment that targets these cells. Aurora-A kinase (Aurora-A) is associated with tumor initiation and progression and is overexpressed in numerous malignancies. The aim of this study is to determine the effect of Aurora-A inhibition in EOC stem cells. EOC stem cells were treated with the Aurora-A inhibitor, MK-5108. Cell growth was monitored by Incucyte real-time imaging system, cell viability was measured using the Celltiter 96 assay and cytokine levels were quantified using xMAP technology. The intracellular changes associated with MK-5108 treatment are: (1) polyploidy and cell cycle arrest; (2) inhibition of NFκB activity; (3) decreased cytokine production; and (4) nuclear accumulation of IκBα. Thus, inhibition of Aurora-A decreases cell proliferation in the EOC stem cells by inducing cell cycle arrest and affecting the NFκB pathway. As EOC stem cells represent a source of recurrence and chemoresistance, these results suggest that Aurora-A inhibition may effectively target the cancer stem cell population in ovarian cancer.Key words: ovarian cancer stem cells, aurora-A kinase, cell cycle arrest, nuclear factor kappaB 相似文献
137.
Haves-Zburof D Paperna T Gour-Lavie A Mandel I Glass-Marmor L Miller A 《Journal of cellular and molecular medicine》2011,15(11):2421-2429
Cathepsins are involved in a variety of physiological processes including antigen processing and presentation and extracellular matrix degradation. In the present study, we evaluated whether expression levels of cathepsins S and B and their inhibitors cystatins B and C are affected by multiple sclerosis (MS) disease state (relapse and remission) and therapies (interferon-β [IFN-β] and the glucocorticoid [GC] methylprednisolone), and whether they are associated with the IFN-β response phenotype. Real-time PCR was employed to compare RNA expression levels in peripheral blood leucocytes (PBLs) and ELISA to determine serum protein levels of MS patients and matched healthy individuals. Cathepsin S RNA was higher in MS patients in the relapse state compared to controls (by 74%, P = 3 × 10(-5), n = 30 versus n = 18) with a similar increase observed in serum (66%, P = 0.002, n = 18 versus n = 20). GC treatment reduced cathepsin S levels in PBL RNA (by 44%, P = 6 × 10(-6), n = 27) and serum proteins (by 27%, P = 1 × 10(-5), n = 26), reduced the serum protein levels of pro-cathepsin B (by 8%, P = 0.0007, n = 23), and in parallel increased the serum levels of their inhibitor cystatin C (by 82%, P = 8 × 10(-6), n = 26). IFN-β therapy significantly elevated the RNA levels (n = 16) of cathepsin B (by 16%, P = 0.03), cystatin B (44%, P = 0.004) and cystatin C (48%, P = 0.011). In the serum, only cathepsin S levels were reduced by IFN-β (16%, P = 0.006, n = 25). Interestingly, pre-treatment serum cathepsin S/cystatin C ratio was higher in 'good responders' to IFN-β therapy compared to patients without a good response (by 94%, P = 0.003). These results suggest that cathepsin S and cystatin C may contribute to disease activity in MS, specifically in a subgroup of patients that are responsive to IFN-β therapy, and that these proteins should be further evaluated as biomarkers in MS. 相似文献
138.
139.
Two different scenarios for the recruitment of evolutionary starting points and their subsequent divergence to give new enzymes have been described. The coincidental, promiscuous starting activity may regard the same reaction chemistry on a new substrate (substrate ambiguity). Alternatively, substrate binding guides the recruitment of an enzyme whose reaction chemistry differs from that of the newly evolving one (catalytic promiscuity). While substrate ambiguity seems to underlie the divergence of most enzyme families, the relative levels of occurrence of these scenarios remain unknown. Screening the Escherichia coli proteome with a comparative series of xenobiotic substrates, we found that substrate ambiguity was, as anticipated, more frequent than reaction promiscuity. However, for at least one unnatural reaction (phosphonoesterase), a promiscuous enzyme was identified only when the substrate was decorated with the naturally abundant phosphate group. These findings support the prevailing hypothesis of chemistry-driven divergence but also suggest that recognition of familiar substrate motifs plays a role. In the absence of enzymes catalyzing the same chemistry, having a familiar, naturally occurring substrate motif (chemophore) such as phosphate may increase the likelihood of catalytic promiscuity. Chemophore anchoring may also find practical applications in identifying catalysts for unnatural reactions. 相似文献
140.