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Prostate cancer is the most commonly diagnosed solid malignancy, and tumor cells eventually transform to castrate resistance through multiple pathways including activation of the androgen receptor via insulin-like growth factor receptor (IGF-1R) signaling involving phospho-AKT (pAKT). In this study, a mixture of herbal extracts, Zyflamend®, was used as a treatment in a model of castrate-resistant prostate cancer using CWR22Rv1 cells. Zyflamend reduced androgen receptor and IGF-1R expression along with a reduction of IGF-1-mediated proliferation of CWR22Rv1 cells. IGF-1 induced downstream AKT phosphorylation; however, the induction of pAKT was not associated with androgen receptor expression. Further, constitutively active form of AKT had no effect on nuclear expression of androgen receptor, indicating that upregulation of pAKT did not promote androgen receptor expression or nuclear translocation in castrate-resistant CWR22Rv1 cells. Conversely, Zyflamend reduced androgen receptor expression following IGF-1 stimulation and in cells overexpressing pAKT. These results demonstrated that Zyflamend inhibited IGF-1-stimulated cell growth, IGF-1R expression, and androgen receptor expression and its nuclear localization, but these effects were not dependent upon phosphatidylinositol 3-kinase/pAKT signaling. In conclusion, Zyflamend decreased cell proliferation and inhibited IGF-1R and androgen receptor expression in a phosphatidylinositol 3-kinase/pAKT independent manner.  相似文献   
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Potentially favorable effects of wine consumption on colorectal cancer (CRC) incidence have been reported, but effects on clinical outcomes are unknown. This case-only analysis was designed to investigate outcomes among familial (n = 141) and sporadic (n = 358) CRC patients enrolled in the University of California Irvine CRC gene-environment study during 1994–1996 based on their reported frequency of wine consumption in the year prior to diagnosis. Cases were categorized as either regular or infrequent wine consumers. Univariate survival rate analyses were estimated using the Kaplan and Meier method and log-rank test. Multivariate survival analyses were performed using Cox proportionalhazards ratios (HRs). Earlier stage at presentation (P = 0.034) was noted for familial (but not sporadic) CRC cases reporting regular wine consumption. An overall survival (OS) benefit was observed for familial (but not sporadic) CRC cases that were regular (10-yr OS = 75%) versus infrequent wine consumers (10-yr OS = 47%; P = 0.002). This survival improvement for familial CRC cases remained after adjustment for age, stage, treatment, and other clinically relevant factors (HR = 0.50, 95% confidence interval = 0.25–0.99). Our findings implicate favorable effects of wine consumption on stage at presentation and survival in CRC, selectively among familial CRC cases.  相似文献   
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The objective of modern vaccine development is the safe generation of protective long-term immune memory, both prophylactic and therapeutic. Live attenuated vaccines generate potent cellular and humoral immunity 0005, 0010 and 0015, but numerous problems exist with these vaccines, ranging from production and storage issues to adverse reactions and reversion to virulence. Subunit vaccines are safer, more stable, and more amenable to mass production. However the protection they produce is frequently inferior to live attenuated vaccines and is typically confined to humoral, and not cellular immunity. Unfortunately, there are presently no subunit vaccines available clinically that are effective at eliciting cellular responses let alone cellular memory [4]. This article will provide and overview of areas of investigation that we see as important for the development of vaccines with the capacity to induce robust and enduring cellular immune responses.  相似文献   
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Eight participants with probable Alzheimer's disease (AD) were trained to recall names of countries using the spaced-retrieval memory intervention. Six training sessions were administered on alternate days over a 2-week period. Half of the participants studied a target country alone and the other half studied a target country along with eight distractor countries. Training stimuli appeared in text-only format in half of the sessions and text with a color photograph of the country in the other sessions. On each trial, participants selected the target at increasingly longer retention intervals, contingent upon successful recall. Results indicated that the mean proportion of correct trials and longest duration achieved increased across training sessions, confirming the success of the spaced-retrieval intervention. Pictorial illustrations enhanced explicit memory for target country names. Implications of these data for current views on memory remediation in cognitively impaired older adults are discussed.  相似文献   
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The purpose of this study was to determine a profile for predicting attrition among older adults involved in a 12-month exercise program. The parent study was a single-blinded randomized controlled trial. The study took place between 2006 and 2009 within a university setting. Older adults (N?=?179) completed baseline assessments of functional performance and psychosocial measures. Participants who were randomized, elected to receive treatment, and did not complete the exercise program were considered “dropouts” (n?=?35). Those who completed the program (n?=?144) were classified as “completers.” A latent profile analysis revealed two distinct patterns of memory complaints, self-efficacy to overcome barriers to exercise, balance performance, and stair performance. Dropouts were nearly twice as likely to be members of the profile that exhibited a higher degree of memory complaints, lower self-efficacy for overcoming exercise barriers, poorer single leg balance, and longer times to walk down stairs. The results provide an initial validation of a profile for discriminating between “dropouts” and “completers,” one that may have considerable utility for screening older adults prior to study entry.  相似文献   
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The nicotinic receptor is a promising drug target currently being investigated for the treatment of cognitive symptoms in schizophrenia. A key step in this process is the development of noninvasive functional neuroimaging biomarkers that can be used to determine if nicotinic agents are eliciting their targeted biological effect, ideally through modulation of a fundamental aspect of neuronal function. To that end, neuroimaging researchers are beginning to understand how nicotinic modulation affects “intrinsic” brain networks to elicit potentially therapeutic effects. An intrinsic network is a functionally and (often) structurally connected network of brain areas whose activity reflects a fundamental neurobiological organizational principle of the brain. This review summarizes findings of the effects of nicotinic drugs on three topics related to intrinsic brain network activity: (1) the default mode network, a group of brain areas for which activity is maximal at rest and reduced during cognitive tasks, (2) the salience network, which integrates incoming sensory data with prior internal representations to guide future actions and change predictive values, and (3) multi-scale complex network dynamics, which describe these brain's ability to efficiency integrate information while preserving local functional specialization. These early findings can be used to inform future neuroimaging studies that examine the network effects of nicotinic agents.  相似文献   
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