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A protocol for a randomised double-blind placebo-controlled feasibility study to determine whether the daily consumption of flavonoid-rich pure cocoa has the potential to reduce fatigue in people with relapsing and remitting multiple sclerosis (RRMS)
Background: Dietary interventions including consumption of flavonoids, plant compounds found in certain foods, may have the ability to improve fatigue. However, to date, no well-designed intervention studies assessing the role of flavonoid consumption for fatigue management in people with MS (pwMS) have been performed. The hypothesis is that the consumption of a flavonoid-rich pure cocoa beverage will reduce fatigue in pwMS. The aim of this study is to determine the feasibility and potential outcome of running a trial to evaluate this hypothesis. Methods: Using a randomised (1:1) double-blind placebo-controlled feasibility study, 40 men and women (20 in each trial arm) with a recent diagnosis (< 10 years) of relapsing and remitting MS (RRMS) and who are over 18 years of age will be recruited from neurology clinics and throughout the Thames Valley community. During a 6-week nutrition intervention period, participants will consume the cocoa beverage, high flavonoid or low flavonoid content, at breakfast daily. At baseline, demographic factors and disease-related factors will be assessed. Fatigue, activity and quality of life, in addition to other measures, will be taken at three visits (baseline, week 3 and week 6) in a university setting by a researcher blinded to group membership. Feasibility and fidelity will be assessed through recruitment and retention, adherence and a quantitative process evaluation at the end of the trial.We will describe demographic factors (age, gender, level of education) as well as disease-related factors (disease burden scores, length of time diagnosed with MS) and cognitive assessment, depression and quality of life and general physical activity in order to characterise participants and determine possible mediators to identify the processes by which the intervention may bring about change. Feasibility (recruitment, safety, feasibility of implementation of the intervention and evaluation, protocol adherence and data completion) and potential for benefit (estimates of effect size and variability) will be determined to inform future planned studies. Results will be presented using point estimates, 95% confidence intervals and p values. Primary statistical analysis will be on an intention-to-treat basis and will use the complete case data set. Discussion: We propose that a flavonoid-enriched cocoa beverage for the management of fatigue will be well received by participants. Further, if it is implemented early in the disease course of people diagnosed with RRMS, it will improve mobility and functioning by modifying fatigue. Trial registration: Registered with ISRCTN Registry. Trial registration No: ISRCTN69897291; Date April 2016
Probabilistic fire spread forecast as a management tool in an operational setting
Background: An approach to predict fire growth in an operational setting, with the
potential to be used as a decision-support tool for fire management, is described and
evaluated. The operational use of fire behaviour models has mostly followed a deterministic
approach, however, the uncertainty associated with model predictions needs
to be quantified and included in wildfire planning and decision-making process during
fire suppression activities. We use FARSITE to simulate the growth of a large wildfire.
Probabilistic simulations of fire spread are performed, accounting for the uncertainty
of some model inputs and parameters. Deterministic simulations were performed for
comparison. We also assess the degree to which fire spread modelling and satellite
active fire data can be combined, to forecast fire spread during large wildfires events.
Results: Uncertainty was propagated through the FARSITE fire spread modelling system
by randomly defining 100 different combinations of the independent input variables
and parameters, and running the correspondent fire spread simulations in order
to produce fire spread probability maps. Simulations were initialized with the reported
ignition location and with satellite active fires. The probabilistic fire spread predictions
show great potential to be used as a fire management tool in an operational setting,
providing valuable information regarding the spatial–temporal distribution of burn
probabilities. The advantage of probabilistic over deterministic simulations is clear
when both are compared. Re-initializing simulations with satellite active fires did not
improve simulations as expected.
Conclusion: This information can be useful to anticipate the growth of wildfires
through the landscape with an associated probability of occurrence. The additional
information regarding when, where and with what probability the fire might be in the
next few hours can ultimately help minimize the negative environmental, social and
economic impacts of these firesinfo:eu-repo/semantics/publishedVersio
Self-renewal and chemotherapy resistance of p75NTR positive cells in esophageal squamous cell carcinomas
<p>Abstract</p> <p>Background</p> <p>p75<sup>NTR </sup>has been used to isolate esophageal and corneal epithelial stem cells. In the present study, we investigated the expression of p75<sup>NTR </sup>in esophageal squamous cell carcinoma (ESCC) and explored the biological properties of p75<sup>NTR+ </sup>cells.</p> <p>Methods</p> <p>p75<sup>NTR </sup>expression in ESCC was assessed by immunohistochemistry. p75<sup>NTR+ </sup>and p75<sup>NTR- </sup>cells of 4 ESCC cell lines were separated by fluorescence-activated cell sorting. Differentially expressed genes between p75<sup>NTR+ </sup>and p75<sup>NTR- </sup>cells were determined by real-time quantitative reverse transcription-PCR. Sphere formation assay, DDP sensitivity assay, <sup>64</sup>copper accumulation assay and tumorigenicity analysis were performed to determine the capacity of self-renewal, chemotherapy resistance and tumorigenicity of p75<sup>NTR+ </sup>cells.</p> <p>Results</p> <p>In ESCC specimens, p75<sup>NTR </sup>was found mainly confined to immature cells and absent in cells undergoing terminal differentiation. The percentage of p75<sup>NTR+ </sup>cells was 1.6%–3.7% in Eca109 and 3 newly established ESCC cell lines. The expression of Bmi-1, which is associated with self-renewal of stem cells, was significantly higher in p75<sup>NTR+ </sup>cells. p63, a marker identified in keratinocyte stem cells, was confined mainly to p75<sup>NTR+ </sup>cells. The expression of CTR1, which is associated with cisplatin (DDP)-resistance, was significantly decreased in p75<sup>NTR+ </sup>cells. Expression levels of differentiation markers, such as involucrin, cytokeratin 13, β1-integrin and β4-integrin, were lower in p75<sup>NTR+ </sup>cells. In addition, p75<sup>NTR+ </sup>cells generated both p75<sup>NTR+ </sup>and p75<sup>NTR- </sup>cells, and formed nonadherent spherical clusters in serum-free medium supplemented with growth factors. Furthermore, p75<sup>NTR+ </sup>cells were found to be more resistant to DDP and exhibited lower <sup>64</sup>copper accumulation than p75<sup>NTR- </sup>cells.</p> <p>Conclusion</p> <p>Our results demonstrated that p75<sup>NTR+ </sup>cells possess some characteristics of CSCs, namely, self-renewal and chemotherapy resistance. Chemotherapy resistance of p75<sup>NTR+ </sup>cells may probably be attributable to decreased expression of CTR1.</p
Expression and Function of Osteopontin in Vascular Adventitial Fibroblasts and Pathological Vascular Remodeling
Osteopontin is known to play important roles in various diseases including vascular disorders. However, little is known about its expression and function in vascular adventitial fibroblasts. Adventitial fibroblasts have been shown to play a key role in pathological vascular remodeling associating with various vascular disorders. In this study, we measured activation of Osteopontin and its biological functions in cultured adventitial fibroblasts and injured rat carotid injury arteries induced by balloon angioplasty. Our results showed that angiotensin II and aldosterone increased Osteopontin expression in adventitial fibroblasts in a time- and concentration-dependent manner. MAPKs and AP-1 pathways were involved in Osteopontin upregulation. In addition, Adventitial fibroblast migration stimulated by Angiotensin II and aldosterone required OPN expression. Perivascular delivery of antisense oligonucleotide for Osteopontin suppressed neointimal formation post-injury. We concluded that upregulation of Osteopontin expression in adventitial fibroblasts might be important in the pathogenesis of vascular remodeling after arterial injury
Prospective purification of perivascular presumptive mesenchymal stem cells from human adipose tissue:process optimization and cell population metrics across a large cohort of diverse demographics
BACKGROUND: Adipose tissue is an attractive source of mesenchymal stem cells (MSC) as it is largely dispensable and readily accessible through minimally invasive procedures such as liposuction. Until recently MSC could only be isolated in a process involving ex-vivo culture and their in-vivo identity, location and frequency remained elusive. We have documented that pericytes (CD45-, CD146+, and CD34-) and adventitial cells (CD45-, CD146-, CD34+) (collectively termed perivascular stem cells or PSC) represent native ancestors of the MSC, and can be prospectively purified using fluorescence activated cell sorting (FACS). In this study we describe an optimized protocol that aims to deliver pure, viable and consistent yields of PSC from adipose tissue. We analysed the frequency of PSC within adipose tissue, and the effect of patient and procedure based variables on this yield. METHODS: Within this twin centre study we analysed the adipose tissue of n = 131 donors using flow cytometry to determine the frequency of PSC and correlate this with demographic and processing data such as age, sex, BMI and cold storage time of the tissue. RESULTS: The mean number of stromal vascular fraction (SVF) cells from 100 ml of lipoaspirate was 34.4 million. Within the SVF, mean cell viability was 83 %, with 31.6 % of cells being haematopoietic (CD45+). Adventitial cells and pericytes represented 33.0 % and 8 % of SVF cells respectively. Therefore, a 200 ml lipoaspirate would theoretically yield 23.2 million viable prospectively purified PSC - sufficient for many reconstructive and regenerative applications. Minimal changes were observed in respect to age, sex and BMI suggesting universal potential application. CONCLUSIONS: Adipose tissue contains two anatomically and phenotypically discreet populations of MSC precursors – adventitial cells and pericytes – together referred to as perivascular stem cells (PSC). More than 9 million PSC per 100 ml of lipoaspirate can be rapidly purified to homogeneity using flow cytometry in clinically relevant numbers potentially circumventing the need for purification and expansion by culture prior to clinical use. The number and viability of PSC are minimally affected by patient age, sex, BMI or the storage time of the tissue, but the quality and consistency of yield can be significantly influenced by procedure based variables. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13287-016-0302-7) contains supplementary material, which is available to authorized users
Trans-specialization understanding in international technology alliances: The influence of cultural distance
In the information age, the firm's performance hinges on combining partners' specialist knowledge to achieve value co-creation. Combining knowledge from different specialties could be a costly process in the international technology alliances (ITAs) context. We argue that the combination of different specializations requires the development of "trans-specialization understanding" (TSU) instead of the internalization of partners' specialist knowledge. This article examines the extent to which inter-firm governance in ITAs shapes TSU, and whether the development of TSU is endangered by cultural distance. We hypothesize that relational governance, product modularity, and cultural distance influence TSU development, which in turn influences firm performance. We collected data from 110 non-equity ITAs between software and hardware firms participating in the mobile device sector. We analyzed the data using partial least squares path modeling. Our findings suggest that TSU largely depends on product modularity and relational governance in alliances. However, while cultural distance negatively moderates the path from relational governance to TSU, it has no effect on the relationship between product modularity and TSU. Based on this, we conclude that product modularity can substitute for relational governance when strong relational norms are not well-developed in international alliances. Thus cultural distance does not invariably amount to a liability in ITAs
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