206 research outputs found

    Physiological changes to the swallowing mechanism following (Chemo)radiotherapy for head and neck cancer: a systematic review

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    Emerging research suggests that preventative swallowing rehabilitation, undertaken before or during (chemo)radiotherapy ([C]RT), can significantly improve early swallowing outcomes for head and neck cancer (HNC) patients. However, these treatment protocols are highly variable. Determining specific physiological swallowing parameters that are most likely to be impacted post-(C)RT would assist in refining clear targets for preventative rehabilitation. Therefore, this systematic review (1) examined the frequency and prevalence of physiological swallowing deficits observed post-(C)RT for HNC, and (2) determined the patterns of prevalence of these key physiological deficits over time post-treatment. Online databases were searched for relevant papers published between January 1998 and March 2013. A total of 153 papers were identified and appraised for methodological quality and suitability based on exclusionary criteria. Ultimately, 19 publications met the study’s inclusion criteria. Collation of reported prevalence of physiological swallowing deficits revealed reduced laryngeal excursion, base-of-tongue (BOT) dysfunction, reduced pharyngeal contraction, and impaired epiglottic movement as most frequently reported. BOT dysfunction and impaired epiglottic movement showed a collective prevalence of over 75 % in the majority of patient cohorts, whilst reduced laryngeal elevation and pharyngeal contraction had a prevalence of over 50 %. Subanalysis suggested a trend that the prevalence of these key deficits is dynamic although persistent over time. These findings can be used by clinicians to inform preventative intervention and support the use of specific, evidence-based therapy tasks explicitly selected to target the highly prevalent deficits post-(C)RT for HNC

    Cimetidine inhibits salivary gland tumor cell adhesion to neural cells and induces apoptosis by blocking NCAM expression

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    <p>Abstract</p> <p>Background</p> <p>Cimetidine, a histamine type-2 receptor antagonist, has been reported to inhibit the growth of glandular tumors such as colorectal cancer, however the mechanism of action underlying this effect is unknown. Adenoid cystic carcinoma is well known as a malignant salivary gland tumor which preferentially invades neural tissues. We demonstrated previously that human salivary gland tumor (HSG) cells spontaneously express neural cell adhesion molecule (NCAM), that HSG cell proliferation may be controlled via a homophilic (NCAM-NCAM) binding mechanism and that NCAM may be associated with perineural invasion by malignant salivary gland tumors. We further demonstrated that cimetidine inhibited NCAM expression and induced apoptosis in HSG cells. Here, we investigated the effects of cimetidine on growth and perineural/neural invasion of salivary gland tumor cells.</p> <p>Methods</p> <p>In this study, we have examined the effect of cimetidine on cancer cell adhesion to neural cells <it>in vitro</it>, one of the critical steps of cancer invasion and metastasis. We have also used an <it>in vivo </it>carcinogenesis model to confirm the effect of cimetidine.</p> <p>Results</p> <p>We have demonstrated for the first time that cimetidine can block the adhesion of HSG cells to neural cell monolayers and that it can also induce significant apoptosis in the tumor mass in a nude mouse model. We also demonstrated that these apoptotic effects of cimetidine might occur through down-regulation of the cell surface expression of NCAM on HSG cells. Cimetidine-mediated down-regulation of NCAM involved suppression of the nuclear translocation of NF-κB, a transcriptional activator of NCAM gene expression.</p> <p>Conclusion</p> <p>These findings suggest that growth and perineural/neural invasion of salivary gland tumors can be blocked by administration of cimetidine via induction of apoptosis and in which NCAM plays a role.</p

    Transphosphorylation of kinase-dead HER3 and breast cancer progression: a new standpoint or an old concept revisited?

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    Although neither kinase-dead human epidermal growth factor receptor (HER)3 nor orphan HER2 can be activated by HER-related ligands on their own, the formation of HER2/HER3 heterodimers creates the most mitogenic and transforming receptor complex within the HER (erbB) family of transmembrane receptor tyrosine kinases. The incorporation of markers such as HER3 transactivation, HER2/HER3 dimer, or others that may provide information regarding the level of HER pathway engagement has been demonstrated to allow identification of patients who respond to or escape HER-targeted therapies. Pioneering studies showed that high expression of kinase-dead HER3 can predict early escape from the anti-HER2 monoclonal antibody trastuzumab. Also, the growth-inhibitory effects of HER1/2 tyrosine kinase inhibitors (TKIs) were previously found to be attenuated in the presence of heregulin, which is a high-affinity combinatorial ligand for HER3. All of these concepts are being revisited with respect to the efficacy of HER family TKI therapies; in particular, HER3 signalling buffered against incomplete inhibition of HER2 kinase activity has been suggested to be the mechanism that allows HER2 over-expressing breast cancer cells to escape HER TKIs. It remains to be elucidated whether reactivation of HER3 signalling can also account for the poor efficacy of HER TKIs in treating breast carcinomas that contain low overall levels of HER2 receptors. However, it appears that regardless of the mechanism that triggers the formation of oncogenic HER2/HER3 heterodimers (HER2 over-expression or overall low HER2 but high levels of the HER3 ligand heregulin), HER3 transphosphorylation is a common response of breast cancer cells upon treatment with current inhibitors of the HER receptor tyrosine kinase network. Because kinase-inactive HER3 is not presently an amenable target for forthcoming HER TKIs, molecular approaches that can efficiently block heregulin-triggered HER3 transactivation or nucleocytoplasmic trafficking of heregulin might offer novel strategies with which to manage HER-driven breast cancer disease

    Using Mitochondrial and Nuclear Sequence Data for Disentangling Population Structure in Complex Pest Species: A Case Study with Dermanyssus gallinae

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    Among global changes induced by human activities, association of breakdown of geographical barriers and impoverishered biodiversity of agroecosystems may have a strong evolutionary impact on pest species. As a consequence of trade networks' expansion, secondary contacts between incipient species, if hybrid incompatibility is not yet reached, may result in hybrid swarms, even more when empty niches are available as usual in crop fields and farms. By providing important sources of genetic novelty for organisms to adapt in changing environments, hybridization may be strongly involved in the emergence of invasive populations

    Is the Public willing to help the Nigerian Police during the Boko Haram crisis? A look at moderating factors.

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    This paper sought the opinion of 200 Nigerians on their willingness to cooperate with the Police during the Boko Haram crisis. Public perceptions of Police effectiveness during the crisis, residence location, gender and religious affiliation were used as moderators. Data was analysed using an explanatory factor analysis and structural equation modelling. Results indicated a strong association between perceived effectiveness and willingness to report to the Police with respondents who question the effectiveness of the Police being less likely to be willing to report criminal activity about Boko Haram. Further to this, the impact of religion on willingness to report was at least partially mediated by perceived effectiveness of the Police with the results showing that Christian respondents perceived the Police as less effective. Females and those living in the North were significantly less willing to report criminal activity to the Police The findings are then discussed in relation to the BH crises and directions for future research are given

    Oxytocin's neurochemical effects in the medial prefrontal cortex underlie recovery of task-specific brain activity in autism: a randomized controlled trial

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    The neuropeptide oxytocin may be an effective therapeutic strategy for the currently untreatable social and communication deficits associated with autism. Our recent paper reported that oxytocin mitigated autistic behavioral deficits through the restoration of activity in the ventromedial prefrontal cortex (vmPFC), as demonstrated with functional magnetic resonance imaging (fMRI) during a socio-communication task. However, it is unknown whether oxytocin exhibited effects at the neuronal level, which was outside of the specific task examined. In the same randomized, double-blind, placebo-controlled, within-subject cross-over clinical trial in which a single dose of intranasal oxytocin (24 IU) was administered to 40 men with high-functioning autism spectrum disorder (UMIN000002241/000004393), we measured N-acetylaspartate (NAA) levels, a marker for neuronal energy demand, in the vmPFC using (1)H-magnetic resonance spectroscopy ((1)H-MRS). The differences in the NAA levels between the oxytocin and placebo sessions were associated with oxytocin-induced fMRI signal changes in the vmPFC. The oxytocin-induced increases in the fMRI signal could be predicted by the NAA differences between the oxytocin and placebo sessions (P=0.002), an effect that remained after controlling for variability in the time between the fMRI and (1)H-MRS scans (P=0.006) and the order of administration of oxytocin and placebo (P=0.001). Furthermore, path analysis showed that the NAA differences in the vmPFC triggered increases in the task-dependent fMRI signals in the vmPFC, which consequently led to improvements in the socio-communication difficulties associated with autism. The present study suggests that the beneficial effects of oxytocin are not limited to the autistic behavior elicited by our psychological task, but may generalize to other autistic behavioral problems associated with the vmPFC

    Daily egg consumption in hyperlipidemic adults - Effects on endothelial function and cardiovascular risk

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    <p>Abstract</p> <p>Background</p> <p>Limiting consumption of eggs, which are high in cholesterol, is generally recommended to reduce risk of cardiovascular disease. However, recent evidence suggests that dietary cholesterol has limited influence on serum cholesterol or cardiac risk.</p> <p>Objective</p> <p>To assess the effects of egg consumption on endothelial function and serum lipids in hyperlipidemic adults.</p> <p>Methods</p> <p>Randomized, placebo-controlled crossover trial of 40 hyperlipidemic adults (24 women, 16 men; average age = 59.9 ± 9.6 years; weight = 76.3 ± 21.8 kilograms; total cholesterol = 244 ± 24 mg/dL). In the acute phase, participants were randomly assigned to one of the two sequences of a single dose of three medium hardboiled eggs and a sausage/cheese breakfast sandwich. In the sustained phase, participants were then randomly assigned to one of the two sequences of two medium hardboiled eggs and 1/2 cup of egg substitute daily for six weeks. Each treatment assignment was separated by a four-week washout period. Outcome measures of interest were endothelial function measured as flow mediated dilatation (FMD) and lipid panel.</p> <p>Results</p> <p>Single dose egg consumption had no effects on endothelial function as compared to sausage/cheese (0.4 ± 1.9 vs. 0.4 ± 2.4%; <it>p </it>= 0.99). Daily consumption of egg substitute for 6 weeks significantly improved endothelial function as compared to egg (1.0 ± 1.2% vs. -0.1 ± 1.5%; <it>p </it>< 0.01) and lowered serum total cholesterol (-18 ± 18 vs. -5 ± 21 mg/dL; <it>p </it>< 0.01) and LDL (-14 ± 20 vs. -2 ± 19 mg/dL; <it>p </it>= 0.01). Study results (positive or negative) are expressed in terms of change relative to baseline.</p> <p>Conclusions</p> <p>Egg consumption was found to be non-detrimental to endothelial function and serum lipids in hyperlipidemic adults, while egg substitute consumption was beneficial.</p

    Fulvestrant-induced expression of ErbB3 and ErbB4 receptors sensitizes oestrogen receptor-positive breast cancer cells to heregulin β1

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    Introduction We have previously reported that induction of epidermal growth factor receptor and ErbB2 in response to antihormonal agents may provide an early mechanism to allow breast cancer cells to evade the growth-inhibitory action of such therapies and ultimately drive resistant cell growth. More recently, the other two members of the ErbB receptor family, ErbB3 and ErbB4, have been implicated in antihormone resistance in breast cancer. In the present study, we have investigated whether induction of ErbB3 and/or ErbB4 may provide an alternative resistance mechanism to antihormonal action in a panel of four oestrogen receptor (ER)-positive breast cancer cell lines. Methods MCF-7, T47D, BT474 and MDAMB361 cell lines were exposed to fulvestrant (100 nM) for seven days, and effects on ErbB3/4 expression and signalling, as well as on cell growth, were assessed. Effects of heregulin β1 (HRGβ1) were also examined in the absence and presence of fulvestrant to determine the impact of ER blockade on the capacity of this ErbB3/4 ligand to promote signalling and cell proliferation. Results Fulvestrant potently reduced ER expression and transcriptional activity and significantly inhibited growth in MCF-7, T47D, BT474 and MDAMB361 cells. However, alongside this inhibitory activity, fulvestrant also consistently induced protein expression and activity of ErbB3 in MCF-7 and T47D cells and ErbB4 in BT474 and MDAMB361 cell lines. Consequently, fulvestrant treatment sensitised all cell lines to the actions of the ErbB3/4 ligand HRGβ1 with enhanced ErbB3/4-driven signalling activity, reexpression of cyclin D1 and significant increases in cell proliferation being observed when compared to untreated cells. Indeed, in T47D and MDAMB361 HRGβ1 was converted from a ligand having negligible or suppressive growth activity into one that potently promoted cell proliferation. Consequently, fulvestrant-mediated growth inhibition was completely overridden by HRGβ1 in all four cell lines. Conclusions These findings suggest that although antihormones such as fulvestrant may have potent acute growth-inhibitory activity in ER-positive breast cancer cells, their ability to induce and sensitise cells to growth factors may serve to reduce and ultimately limit their inhibitory activity

    Entrepreneurial orientation and the business performance of SMEs: a quantitative study from the Netherlands

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    Entrepreneurial Orientation (EO) is often mentioned as an antecedent of growth, competitive advantage and superior performance, and prior empirical research has often shown a positive relationship between EO and performance appears to exist. However, an important question that remains unanswered is what effect EO might have on firm performance during periods of economic crisis, and the severe environmental turbulence that accompany such crises. This research is a first investigation towards the effects of EO on the performance of small and medium sized firms during the current global economic crisis. In this study we use the multidimensional model of EO and test a series of hypotheses pertaining to its performance effects using survey data gathered from 164 Dutch SMEs. The present research shows that proactive firm behavior positively contributes to SME performance during the economic crisis. We further show that innovative SMEs do perform better in turbulent environments, but those innovative SMEs should minimize the level of risk and should take action to avoid projects that are too risky
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