743 resultados para participation in STEM
Resumo:
SPINK5 (serine protease inhibitor Kazal-type 5) encodes the putative proteinase inhibitor LEKTI (lympho-epithelial Kazal-type related inhibitor). In skin, LEKTI expression is restricted to the stratum granulosum of the epidermis and the inner root sheath of hair follicles. Mutations that create premature termination codons in SPINK5 have been reported as the cause of Netherton syndrome (NS), a human autosomal recessive disorder characterized by congenital ichthyosis with defective cornification, a specific hair shaft defect known as trichorrexis invaginata or 'bamboo hair', and severe atopic manifestations, including atopic dermatitis and hayfever. Althought recombinant human LEKTI inhibits a battery of serine proteases including plasmin, trypsin, subtilisin A, cathepsin G, and elastase, the precise role of LEKTI in the physiopathology of NS remains unclear. Spink5−/− mice display a NS-like phenotype. Surprisingly, a psoriasis-like hyperplasia, basement membrane breakdown followed by evagination of spindle-shaped epidermal cells into the dermal compartment, and the presence of numerous sweat gland-like structures were also observed when the skin of Spink5−/− newborn mice, which die at birth, was transplanted onto the back of nude mice. Collectively, these observations suggest that LEKTI may play a role on cell proliferation and stem cell fate. Our current work aims at elucidating the mechanisms by which LEKTI impact these biological processes. Using keratinocyte stem cells obtained from NS patients, we have identified LEKTI as a regulator node in several signaling pathways involved in stem cell behavior.
Resumo:
Objective: This study assesses differences in adiposity, aerobic fitness, and lifestyle characteristics in preschoolers according to their weight status and sports club (SC) participation. Method: As part of the Ballabeina study, 600 randomly selected preschoolers (mean age 5.1 ± 0.6 years; 50.2% girls) were analyzed. Body composition was measured by bioelectrical impedance, aerobic fitness by the 20-meter shuttle run test, and physical activity by accelerometers. Eating habits, media use, and SC participation were assessed by questionnaires. Results: Overweight children (Swiss national percentiles) and children not participating in SC had both lower aerobic fitness and higher % body fat compared to their respective counterparts (all p ≤ 0.028). In addition, children not participating in SC were less physically active, had more media use, and ate less healthy compared to children participating in SC (all p ≤ 0.023). Controlling for parental sociocultural determinants attenuated differences in % body fat, in physical activity, and in eating habits. Conclusion: Aerobic fitness differs both according to weight status and SC participation in preschoolers. Furthermore, in view of the many differences in lifestyle behaviors, SC participation at this age could represent a more discriminatory indicator of healthy lifestyle characteristics than weight status.
Resumo:
To study telomere length dynamics in hematopoietic cells with age, we analyzed the average length of telomere repeat sequences in diverse populations of nucleated blood cells. More than 500 individuals ranging in age from 0 to 90 yr, including 36 pairs of monozygous and dizygotic twins, were analyzed using quantitative fluorescence in situ hybridization and flow cytometry. Granulocytes and naive T cells showed a parallel biphasic decline in telomere length with age that most likely reflected accumulated cell divisions in the common precursors of both cell types: hematopoietic stem cells. Telomere loss was very rapid in the first year, and continued for more than eight decades at a 30-fold lower rate. Memory T cells also showed an initial rapid decline in telomere length with age. However, in contrast to naive T cells, this decline continued for several years, and in older individuals lymphocytes typically had shorter telomeres than did granulocytes. Our findings point to a dramatic decline in stem cell turnover in early childhood and support the notion that cell divisions in hematopoietic stem cells and T cells result in loss of telomeric DNA.
Resumo:
The number of cell divisions in hematopoietic stem cells (HSCs) following transplantation of bone marrow or mobilized peripheral blood into myelo-ablated recipients is unknown. This number is expected to depend primarily on the number of transplanted stem cells, assuming that stem cells do not differ in engraftment potential and other functional properties. In a previous study, we found that the telomere length in circulating granulocytes in normal individuals shows a biphasic decline with age, most likely reflecting age-related changes in the turnover of HSCs. In order to study HSCs' proliferation kinetics following stem cells transplantation, we analyzed the telomere length in donor-derived nucleated blood cells in four HLA-matched bone marrow transplant recipients relative to comparable cells from the sibling donors. In each case, the telomeres in granulocytes were shorter in the recipient than in the donor. This difference was established in the first year post transplantation and did not change after that. The telomere length in naïve and memory T cells showed marked differences after transplantation, complicating the interpretation of telomere length data using unseparated nucleated blood cells. Interestingly, the telomere length in naïve T cells that were first observed six months post transplantation was very similar in donor and recipient pairs. Our observations are compatible with a limited number of additional cell divisions in stem cell populations after bone marrow transplantations and support the idea that different populations of stem cells contribute to short-term myeloid and long-term lympho myeloid hematopoiesis.
Resumo:
Most corporate codes of conduct and multi-stakeholder sustainability standards guarantee workers' rights to freedom of association and collective bargaining, but many authors are sceptical about the concrete impact of codes and standards of this kind. In this paper we use Hancher and Moran's (1998) concept of 'regulatory space' to assess the potential of private transnational regulation to support the growth of trade union membership and collective bargaining relationships, drawing on some preliminary case study results from a project on the impact of the International Finance Corporation's (IFC) social conditionality on worker organization and social dialogue. One of the major effects of neoliberal economic and industrial policy has been the routine exclusion of workers' organizations from regulatory processes on the grounds that they introduce inappropriate 'political' motives into what ought to be technical decision-making processes. This, rather than any direct attack on their capacity to take action, is what seems best to explain the global decline in union influence (Cradden 2004; Howell 2007; Howe 2012). The evidence we present in the paper suggests that private labour regulation may under certain conditions contribute to a reversal of this tendency, re-establishing the legitimacy of workers' organizations within regulatory processes and by extension the legitimacy of their use of economic and social power. We argue that guarantees of freedom of association and bargaining rights within private regulation schemes are effective to the extent that they can be used by workers' organizations in support of a claim for access to the regulatory space within which the terms and conditions of the employment relationship are determined. Our case study evidence shows that certain trade unions in East Africa have indeed been able to use IFC and other private regulation schemes as levers to win recognition from employers and to establish collective bargaining relationships. Although they did not attempt to use formal procedures to make a claim for the enforcement of freedom of association rights on behalf of their members, the unions did use enterprises' adherence to private regulation schemes as a normative point of reference in argument and political exchange about worker representation. For these unions, the regulation was a useful addition to the range of arguments that they could deploy as means to justify their demand for recognition by employers. By contrast, the private regulation that helps workers' organizations to win access to regulatory processes does little to ensure that they are able to participate meaningfully, whether in terms of technical capacity or of their ability to mobilize social power as a counterweight to the economic power of employers. To the extent that our East African unions were able to make an impact on terms and conditions of employment via their participation in regulatory space it was solely on the basis of their own capacities and resources and the application of national labour law.
Resumo:
BACKGROUND: There is an urgent need to assess and improve the consent process in clinical trials of innovative therapies for neurodegenerative disorders. METHODS: We performed a longitudinal study of the consent of Huntington's disease patients during the Multicenter Fetal Cell Intracerebral Grafting Trial in Huntington's Disease (MIG-HD) in France and Belgium. Patients and their proxies completed a consent questionnaire at inclusion, before signing the consent form and after one year of follow-up, before randomization and transplantation. The questionnaire explored understanding of the protocol, satisfaction with the information delivered, reasons for participating in the trial and expectations regarding the transplant. Forty-six Huntington's disease patients and 27 proxies completed the questionnaire at inclusion, and 27 Huntington's disease patients and 16 proxies one year later. RESULTS: The comprehension score was high and similar for Huntington's disease patients and proxies at inclusion (72.6% vs 77.8%; P > 0.1) but only decreased in HD patients after one year. The information satisfaction score was high (73.5% vs 66.5%; P > 0.1) and correlated with understanding in both patients and proxies. The motivation and expectation profiles were similar in patients and proxies and remained unchanged after one year. CONCLUSIONS: Cognitively impaired patients with Huntington's disease were capable of consenting to participation in this trial. This consent procedure has presumably strengthened their understanding and should be proposed before signing the consent form in future gene or cell therapy trials for neurodegenerative disorders. Because of the potential cognitive decline, proxies should be designated as provisional surrogate decision-makers, even in competent patients.
Resumo:
The purpose of this article is to offer a practical approach to the new European dimension for regional parliaments signified by the entry into force of the Treaty of Lisbon. The parliamentary scrutiny of subsidiarity by way of the early warning system has assigned a new mission to legislative assemblies with the aim of reinforcing the intervention of regions in the drafting of policies by Union institutions. In the Spanish case, the institutionalisation of this mechanism came about with Act nº 24/2009, which attributes to the Joint Committee for the European Union, in the name of the Cortes Generales [the Spanish Parliament], the function of receiving the proposals for legislative acts by the EU and transferring them to the regional parliaments in order for the latter to issue, in a brief period of four weeks, a report on compliance with the principle of subsidiarity. The majority of regional parliaments have also carried out normative reforms to regulate the procedure of participation in the early warning system.
Resumo:
This article focuses on the analysis of the regulatory framework of citizen participation in the local government, which organises direct and participatory democracy at the local level, and identifies the laws and mechanisms through which the constitutional requirements for participation are accomplished. Mu nicipalities, the authority closest to citizens, are the best level of government since they directly involve civil society in the decision-making process experiencing the scope and appropriateness of the instruments by which it is channeled.
Resumo:
Hypoxia elicits hyperventilation and hypothermia, but the mechanisms involved are not well understood. The nitric oxide (NO) pathway is involved in hypoxia-induced hypothermia and hyperventilation, and works as a neuromodulator in the central nervous system, including the locus coeruleus (LC), which is a noradrenergic nucleus in the pons. The LC plays a role in a number of stress-induced responses, but its participation in the control of breathing and thermoregulation is unclear. Thus, in the present study, we tested the hypothesis that LC plays a role in the hypoxia-induced hypothermia and hyperventilation, and that NO is involved in these responses. Electrolytic lesions were performed bilaterally within the LC in awake unrestrained adult male Wistar rats weighing 250-350 g. Body temperature and pulmonary ventilation (VE) were measured. The rats were divided into 3 groups: control (N = 16), sham operated (N = 7) and LC lesioned (N = 19), and each group received a saline or an NG-nitro-L-arginine methyl ester (L-NAME, 250 µg/µl) intracerebroventricular (icv) injection. No significant difference was observed between control and sham-operated rats. Hypoxia (7% inspired O2) caused hyperventilation and hypothermia in both control (from 541.62 ± 35.02 to 1816.18 ± 170.7 and 36.3 ± 0.12 to 34.4 ± 0.09, respectively) and LC-lesioned rats (LCLR) (from 694.65 ± 63.17 to 2670.29 ± 471.33 and 36 ± 0.12 to 35.3 ± 0.12, respectively), but the increase in VE was higher (P<0.05) and hypothermia was reduced (P<0.05) in LCLR. L-NAME caused no significant change in VE or in body temperature under normoxia, but abolished both the hypoxia-induced hyperventilation and hypothermia. Hypoxia-induced hyperventilation was reduced in LCLR treated with L-NAME. L-NAME also abolished the hypoxia-induced hypothermia in LCLR. The present data indicate that hypoxia-induced hyperventilation and hypothermia may be related to the LC, and that NO is involved in these responses.
Resumo:
Epigenetic mechanisms such as DNA methylation and histone modification are important in stem cell differentiation. Methylation is principally associated with transcriptional repression, and histone acetylation is correlated with an active chromatin state. We determined the effects of these epigenetic mechanisms on adipocyte differentiation in mesenchymal stem cells (MSCs) derived from bone marrow (BM-MSCs) and adipose tissue (ADSCs) using the chromatin-modifying agents trichostatin A (TSA), a histone deacetylase inhibitor, and 5-aza-2′-deoxycytidine (5azadC), a demethylating agent. Subconfluent MSC cultures were treated with 5, 50, or 500 nM TSA or with 1, 10, or 100 µM 5azadC for 2 days before the initiation of adipogenesis. The differentiation was quantified and expression of the adipocyte genes PPARG and FABP4 and of the anti-adipocyte gene GATA2 was evaluated. TSA decreased adipogenesis, except in BM-MSCs treated with 5 nM TSA. Only treatment with 500 nM TSA decreased cell proliferation. 5azadC treatment decreased proliferation and adipocyte differentiation in all conditions evaluated, resulting in the downregulation of PPARG and FABP4 and the upregulation of GATA2. The response to treatment was stronger in ADSCs than in BM-MSCs, suggesting that epigenetic memories may differ between cells of different origins. As epigenetic signatures affect differentiation, it should be possible to direct the use of MSCs in cell therapies to improve process efficiency by considering the various sources available.
Resumo:
This correlational study investigated the psychological types, learning style preferences, readiness for self-directed learning, demographic and continuing education participation data of 154 registered nurses at two different Southern Ontario hospitals. One hospital was a large tertiary care university-affiliated teaching centre (Cityview) and the other was a smaller secondary care community hospital (Waterview). The instruments used in the study were the PET Type Check, Kolb's Learning Style Inventory, the Self-Directed Readiness Scale (SDLRS), and a Nursing Survey developed by the researcher. Descriptive statistics, crosstabulations and correlational analyses were calculated. The most common psychological types identified among this sample of nurses were extraverted thinking, introverted intuitive and extraverted intuitive. There were no significant differences between the two hospitals. The accommodator learning style was preferred overall, with more nurses at Waterview Hospital preferring the diverger learning style, and more nurses at Cityview Hospital preferring the accommodator learning style. The majority of nurses scored in the average and above average categories on the SDLRS, indicating that they perceive themselves as ready to engage in self-directed learning. At Cityview Hospital there were more nurses in the average and high readiness categories, whereas at Waterview Hospital more nurses scored in the below average category. No significant correlations were found for learning style with psychological type, or for learning style with SDLRS scores. A positive correlation was found to exist between SDLRS scores and each of the psychological types extraverted feelings, extraverted thinking, and introverted intuitive.The only significant correlation for psychological type and continuing education activity was a positive correlation between extraverted thinking types and participation in informal discussion or study groups. Positive correlations were found for SDLRS scores with each of the following continuing education activities; number of hours per month spent reading journals; journal reading; attendance at credit courses; watching videos; using reference texts. Further details of the results are included as well as a discussion of the findings and implications for future research.
Resumo:
Changes in the configuration of a tree stern result insignificant differences in its total volume and in the proportion of that volume that is merchantable timber. Tree allometry, as represented by stem-fo~, is the result of the vertical force of gravity and the horizontal force of wind. The effect of wind force is demonstrated in the relationship between stem-form, standclosure and site-conditions. An increase in wind force on the individual tree due to a decrease in stand density should produce a more tapered tree. The density of the stand is determined by the conditions that the trees are growing under. The ability of the tree to respond to increased wind force may also be a function of these conditions . This stem-form/stand-closure/site-conditions relationship was examined using a pre-existing database from westcentral Alberta. This database consisted of environmental, vegetation, soils and timber data covering a wide range of sites. There were 653 sample trees with 82 variables that formed the basis of the analysis. There were eight tree species consisting of Pinus contorta, Picea mariana, Picea engelmannii x glauca, Abies lasiocarpa, Larix laricina, Populus tremuloides, Betula papyrifera and Populus balsamifera plus a comprehensive all-species data set. As the actual conformation of the stern is very individual, stem-fo~was represented by the diameter at breast height to total height r~tio. The four stand-closure variables, crown closure, total basal area, total volume and total number of stems were reduced to total basal area and total number of stems utilizing a bivariate correlation matrix by species. Site-conditions were subdivided into macro, meso and micro variables and reduced in number 3 using cross-tabulations, bivariate correlation and principal components analysis as screening tools. The stem-fo~/stand-closure relationship was examined using bivariate correlation coefficients for stem-fo~ with total number of stems and stem-fo~ with total basal area. The stem-fo~/site-conditions and the stand-closure/site- conditions relationships were examined using multiple correlation coefficients. The stem-form/stand-closure/site-conditions relationship was examined using multiple correlation coefficients in separate analyses for both total number of stems and total basal area. An increase in stand-closure produced a decrease in stem-form for both total number of stems and total basal area for most species. There was a significant relationship between stem-form and site-conditions and between stand-closure and site-conditions for both total number of stems and total basal area for most species. There was a significant relationship between the stemform and site-conditions, including the stand-closure, for most species; total number of stems was involved independently of the site-conditions in the prediction of stem-form and total basal area was not. Larix laricina and Betula papyrifera were the exceptions to the trends observed with most species. The influence of both stand-closure (total number of stems in particular) and site-conditions (elevation in particular) suggest that forest management practices should include these- ecological parameters in determining appropriate restocking levels.
Resumo:
The brain stems (13S) of streptozotocin (STZ)-diabetic rats were studied lo see the changes in neurotransmitter content and their receptor regulation. The norepinephrine (NE) content determined in the diabetic brain stems did ^ control. an E showed la while PI turnover hri content increased significantly compared N^r eNveFa o the recep significant increase. The alpha2 adrenergic receptor IneP utisoulinntreat d ratsetheNE contentt dec^ sled was significantly reduced during diabetes. in versedcto reanorm sed ulcrea e tK reatment the state. while EPI content remained increased as in die diabetic B,, for a]pha2 adrenergic receptors slw^nificantly while Unlabelled clonidine inhibited [31-I]NE binding in BS of control, diabetic and insulin treated ulations bindi diabetic rats showed that alpha2 adrenergicre^ punks cojnidiabetic animal the ligand bound sites with Hill slopes significantly away from unity. weaker to the low affinity site than in controls. Insulin treatment reversed[ this allumbmn to control levels. The displacement analysis using (-)-epinephrine age in control and diabetic animals revealed two populations of receptor affinidtyo=tat ss. In control animals, when GTP analogue added with epinephrine, the curve nagnlde caofnfitnroit yS model; but in the diabetic BS this effect `not aobserved. In bintact oth the diabetic data thus showlthat the effects of monovalent cations on affinity alphaz adrenergic receptors have a reduced affinity v due in stem ialtered Itscppeomson(5- regulation. The serotonin (5-HT) coat hydroxy) tryptophan (5-HTP) showed an increase and its breakdown metabolite (5-hydroxy) indoleacetic acid (5-I{IAA) showed a significant decrease. This showed that in serotonergic which l nerves there is a disturbance in both synthetic and breankduomwnbers pretma'med ana increased 5-HT. The high affinity serotonin receptor um ese serotonerg decrease in the receptor affinity. The insulin ^treatmentsturtiy showsha decreased serotonergic receptor kinetic parameters to control level. receptor function. These changes in adrenergic and serotonergic receptor function were suggested to be important in insulin function during STZ diabetes.
Resumo:
The white paper ‘Pharmacy in England’ advocates establishing a new pharmacy regulator, building leadership and integrating undergraduate education.[1] Students must morph into competent pharmacists with the skills, expertise and confidence to lead the profession to 2020 and beyond.[2] One way individuals are encouraged to ‘professionalise’ is through participation in personal/professional development schemes. The British Pharmaceutical Students’ Association (BPSA) and the College of Pharmacy Practice have operated a professional development certificate (PDC) scheme since 2001. The scheme rewards students with a joint certificate for evidence of participation in five accredited activities in one academic year. Although the scheme is relevant to development of students, less than 2% of BPSA members take part annually. We wanted to understand the reasons for the low uptake. Our primary objectives were to examine the portrayal of the scheme and to investigate what it signifies to individuals. We describe our attempts to apply social marketing techniques[3] to the PDC, and we use ‘logical levels of change’[4] to highlight a paradox with personal identity.
Resumo:
Adult or somatic stem cells are tissue-resident cells with the ability to proliferate, exhibit self-maintenance as well as to generate new cells with the principal phenotypes of the tissue in response to injury or disease. Due to their easy accessibility and their potential use in regenerative medicine, adult stem cells raise the hope for future personalisable therapies. After infection or during injury, they are exposed to broad range of pathogen or damage-associated molecules leading to changes in their proliferation, migration and differentiation. The sensing of such damage and infection signals is mostly achieved by Toll-Like Receptors (TLRs) with Toll-like receptor 4 being responsible for recognition of bacterial lipopolysaccharides (LPS) and endogenous danger-associated molecular patterns (DAMPs). In this review, we examine the current state of knowledge on the TLR4-mediated signalling in different adult stem cell populations. Specifically, we elaborate on the role of TLR4 and its ligands on proliferation, differentiation and migration of mesenchymal stem cells, hematopoietic stem cells as well as neural stem cells. Finally, we discuss conceptual and technical pitfalls in investigation of TLR4 signalling in stem cells.