44 resultados para GHS-R1a


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The objective was to determine the concentration of total selenium (Se) and the proportion of total Se comprised as selenomethionine (SeMet) and selenocysteine (SeCys), as well as meat quality in terms of oxidative stability in post mortem tissues of lambs offered diets with an increasing dose rate of selenized enriched yeast (SY), or sodium selenite (SS). Fifty lambs were offered, for a period of 112 d, a total mixed ration which had either been supplemented with SY (0, 0.11, 0.21 or 0.31 mg/kg DM to give total Se contents of 0.19, 0.3, 0.4 and 0.5 mg Se/kg DM for treatments T1, T2, T3 and T4, respectively) or SS (0.11 mg/kg DM to give 0.3 mg Se/kg DM total Se [T5]). At enrolment and at 28, 56, 84 and 112 d following enrolment, blood samples were taken for Se and Se species determination, as well as glutathione peroxidase (GSH-Px) activity. At the end of the study lambs were euthanased and samples of heart, liver, kidney, and skeletal muscle were retained for Se and Se species determination. Tissue GSH-Px activity and thiobarbituric acid reactive substances (TBARS) were determined in Longissimus Thoracis. The incorporation into the diet of ascending concentrations of Se as SY increased whole blood total Se and the proportion of total Se comprised as SeMet, and erythrocyte GSH-Px activity. Comparable doses of SS supplementation did not result in significant differences between these parameters. With the exception of kidney tissue, all other tissues showed a dose dependant response to increasing concentrations of dietary SY, such that total Se and SeMet increased. Selenium content of Psoas Major was higher in animals fed SY when compared to a similar dose of SS, indicating improvements in Se availability and retention. There were no significant treatment effects on meat quality assessments GHS-Px and TBARS, reflecting the lack of difference in the proportion of total Se that was comprised as SeCys. However, oxidative stability improved marginally with ascending tissue Se content, providing an indication of a linear dose response whereby TBARS improved with ascending SY inclusion.

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The conventional method for the assessment of acute dermal toxicity (OECD Test Guideline 402, 1987) uses death of animals as an endpoint to identify the median lethal dose (LD50). A new OECD Testing Guideline called the dermal fixed dose procedure (dermal FDP) is being prepared to provide an alternative to Test Guideline 402. In contrast to Test Guideline 402, the dermal FDP does not provide a point estimate of the LD50, but aims to identify that dose of the substance under investigation that causes clear signs of nonlethal toxicity. This is then used to assign classification according to the new Globally Harmonised System of Classification and Labelling scheme (GHS). The dermal FDP has been validated using statistical modelling rather than by in vivo testing. The statistical modelling approach enables calculation of the probability of each GHS classification and the expected numbers of deaths and animals used in the test for imaginary substances with a range of LD50 values and dose-response curve slopes. This paper describes the dermal FDP and reports the results from the statistical evaluation. It is shown that the procedure will be completed with considerably less death and suffering than guideline 402, and will classify substances either in the same or a more stringent GHS class than that assigned on the basis of the LD50 value.

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The conventional method for the assessment of acute inhalation toxicity (OECD Test Guideline 403, 1981) uses death of animals as an endpoint to identify the median lethal concentration (LC50). A new OECD Testing Guideline called the Fixed Concentration Procedure (FCP) is being prepared to provide an alternative to Test Guideline 403. Unlike Test Guideline 403, the FCP does not provide a point estimate of the LC50, but aims to identify an airborne exposure level that causes clear signs of nonlethal toxicity. This is then used to assign classification according to the new Globally Harmonized System of Classification and Labelling scheme (GHS). The FCP has been validated using statistical simulation rather than byin vivo testing. The statistical simulation approach predicts the GHS classification outcome and the numbers of deaths and animals used in the test for imaginary substances with a range of LC50 values and dose response curve slopes. This paper describes the FCP and reports the results from the statistical simulation study assessing its properties. It is shown that the procedure will be completed with considerably less death and suffering than Test Guideline 403, and will classify substances either in the same or a more stringent GHS class than that assigned on the basis of the LC50 value.

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The fixed-dose procedure (FDP) was introduced as OECD Test Guideline 420 in 1992, as an alternative to the conventional median lethal dose (LD50) test for the assessment of acute oral toxicity (OECD Test Guideline 401). The FDP uses fewer animals and causes less suffering than the conventional test, while providing information on the acute toxicity to allow substances to be ranked according to the EU hazard classification system. Recently the FDP has been revised, with the aim of providing further reductions and refinements, and classification according to the criteria of the Globally Harmonized Hazard Classification and Labelling scheme (GHS). This paper describes the revised FDP and analyses its properties, as determined by a statistical modelling approach. The analysis shows that the revised FDP classifies substances for acute oral toxicity generally in the same, or a more stringent, hazard class as that based on the LD50 value, according to either the GHS or the EU classification scheme. The likelihood of achieving the same classification is greatest for substances with a steep dose-response curve and median toxic dose (TD50) close to the LD50. The revised FDP usually requires five or six animals with two or fewer dying as a result of treatment in most cases.

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Low-protein diet impairs insulin secretion in response to nutrients and may induce several metabolic disorders including diabetes, obesity, and cardiovascular disease. In the present study, the influence of leucine supplementation on glutamate dehydrogenase (GDH) expression and glucose-induced insulin secretion (GIIS) was investigated in malnourished rats. Four groups were fed with different diets for 12 weeks: a normal-protein diet (17%) without or with leucine supplementation or a low (6%)-protein diet without (LP) or with leucine supplementation (LPL). Leucine (1.5%) was supplied in the drinking water. Western blotting analysis revealed reduced GIN! expression in LP, whereas LPL displayed improved GDH expression, similar to control. The GHS and leucinc-induced insulin release were also enhanced in LPL compared with LP and similar to those observed in rats fed a normal-protein diet without leucine supplementation. In addition, GDH allosteric activators produced an increased insulin secretion in LPL. These findings indicate that leucine supplementation was able to increase GDH expression leading to Cl IS restoration, probably by improved leucine metabolic pathways. (C) 2010 Elsevier Inc. All rights reserved.

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To address increasing rates of overweight and obesity, a population-based telephone intervention was introduced in New South Wales, Australia. The Get Healthy Information and Coaching Service® (GHS) offered participants a 6-month coaching program or detailed self-help information. Determining the population reach of GHS is of public health importance to ensure that the program reaches disadvantaged groups. This paper describes the socio-demographic and risk profile of participants (n = 4828) in the first 18 months of operations, determines how representative they are of the population, assesses changes in participants’ socio-demographic profile and compares ‘information-only’ and ‘coaching’ participants. The results show that GHS users are representative of the adult population in relation to education, employment status, Aboriginal status, fruit and vegetable consumption and alcohol use. However, more female, middle-aged, English-speaking, rural and socially disadvantaged adults participated in GHS. Coaching Participants were more likely to be overweight and to be ex-smokers than the general population. There was substantial variability in GHS recruitment, when mass-reach television advertising was used, participants enrolled from a major city and from more disadvantaged communities. The GHS has broader population reach than many local interventions, but further efforts are needed to increase reach by Aboriginal communities, other minorities and men.

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JUSTIFICATIVA E OBJETIVOS: O conhecimento de indicadores de qualidade de vida (QV) relacionados à saúde bucal é especialmente relevante para a Odontologia considerando o impacto que as condições bucais podem provocar no bem estar psicológico e social. Estudos sobre aspectos psicossociais contribuem para maior integração da conduta clínica e assistencial, preocupação compartilhada com profissionais da saúde. Integrar as áreas de Psicologia e Odontologia quebrando paradigmas interdisciplinares e o interesse em conhecer os aspectos psicológicos dos pacientes, motivou a realização deste estudo. O objetivo deste estudo foi avaliar a QV dos pacientes com disfunção temporomandibular e/ou dor orofacial. MÉTODO: Foi aplicado o Questionário Genérico de Avaliação de Qualidade de Vida - Medical Outcomes Study 36 - Item Short Health Survey (SF-36) a 91 pacientes, que buscaram atendimento por apresentarem sinais e/ou sintomas de disfunção temporomandibular (DTM) e dor orofacial (DOF). O SF-36 avalia 8 domínios: capacidade funcional (CF), aspectos físicos (AF), dor, estado geral de saúde (EGS), saúde mental (SM), aspectos emocionais (AE), aspectos sociais (AS) e vitalidade (V). RESULTADOS: A análise estatística descritiva e inferencial pela Correlação de Pearson (p-valor < 0,05) demonstrou, com exceção da capacidade funcional (73,2), valores médios entre 50 e 64 para os demais domínios: AF - 57,6; Dor - 50; EGS - 54,5; V - 53,4; AS - 63,6; AE - 51,8; SM - 58. Considerando-se que a pontuação varia de 0 a 100, ou seja, do pior para o melhor estado de saúde, os valores médios foram baixos. Verificou-se correlação entre CF e EGS (p-valor 0,01), tendência de significância para dor e EGS (p-valor 0,07). CONCLUSÃO: Os aspectos dor e capacidade funcional interferem no estado geral de saúde; os pacientes com DTM e DOF sofreram impacto negativo na qualidade de vida pelo prejuízo dos aspectos físicos e mentais.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Es wurde untersucht, wie sich das Substitutionsmuster organischer Peroxyradikale (RO2) auf die Ratenkonstante k1 und die Verzweigungsverhältnisse α, β und γ der Reaktionen von RO2 mit HO2 auswirkt. Die Effekte der Deuterierung von HO2 wurden ebenfalls studiert. Für zwei RO2 wurde zusätzlich das UV-Absorptionsspektrum bestimmt.rnrn αrnRO2 + HO2 → RO + OH + O2 R1arnrn βrn → RO2H + O2 R1brnrn γrn → ROH + O3 R1crnrnIn dieser Arbeit wurde ein neues Experiment aufgebaut. Für die direkte und zeitaufgelöste Messung der OH-Konzentration wurde das Verfahren der Laser-induzierten Fluoreszenz angewendet. Die Radikalerzeugung erfolgte mittels gepulster Laserphotolyse, wodurch unerwünschte Nebenreaktionen weitgehend unterdrückt werden konnten. Mittels transienter Absorptionsspektroskopie konnten die Menge der photolytisch erzeugten Radikale bestimmt und die Ozonbildung über R1c quantifiziert werden. Für die Auswertung wurden kinetische Modelle numerisch an die Messdaten angepasst. Um die experimentellen Unsicherheiten abzuschätzen, wurde ein Monte-Carlo-Ansatz gewählt.rnrnk1 und α reagieren sehr empfindlich auf Veränderungen des RO2-Substitutionsmusters. Während sich eine OH-Bildung für das unsubstituierte C2H5O2 (EtP) mit α EtP ≤ 5 % nicht nachweisen lässt, stellt R1a bei den α-Oxo-substituierten H3CC(O)O2 (AcP) und HOCH2C(O)O2 (HAP) mit α AcP = (63 ± 11) % bzw. α HAP = (69 ± 12) % den Hauptkanal dar. Wie die mit α HEP = (10 ± 4) % geringfügige OH-Bildung bei HOC2H4O2 (HEP) zeigt, nimmt die OH-Gruppe in β-Stellung weniger Einfluss auf den Wert von α als die Oxogruppe in α-Stellung. Bei der Erzeugung α-Oxo-substituierter RO2 kann ebenfalls OH entstehen (R+O2→RO2/OH). Die Druckabhängigkeit dieser OH-Quelle wurde mit einem innovativen Ansatz bestimmt. Mit γ AcP = (15+5-6) % bzw. γ HAP = (10+2-3) % lässt sich für die Reaktionen der α-Oxo-substituierten RO2 eine erhebliche Ozonbildung nachweisen. Durch die Einführung der α-Oxogruppe steigt k1 jeweils um 1,3 • 10-11 cm3s-1 an, der Effekt der β-Hydroxygruppe ist halb so groß (k1 AcP = (2,0 ± 0,4) • 10-11 cm3s-1, k1 HAP = (2,6 ± 0,4) • 10-11 cm3s-1). Das Verzweigungsverhältnis α steigt weiter, wenn das HO2 deuteriert wird (α AcP,iso = (80 ± 14) %, k1 AcP,iso = (2,1 ± 0,4) • 10-11 cm3s-1). Vergleiche mit älteren Studien zeigen, dass die OH-Bildung über R1a bislang deutlich unterschätzt worden ist. Die möglichen Ursachen für die Unterschiede zwischen den Studien werden ebenso diskutiert wie die Hintergründe der beobachteten Substituenteneffekte.

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To date, the negotiations over chemicals in the Translatlantic Trade and Investment Partnership (TTIP) have not shown sufficient ambition. The talks have focused too much on the differences in the two ‘systems’, rather than on the actual levels of health and environmental protection for substances regulated by both the US and the EU. Given the accomplishments within the OECD and the UN Globally Harmonised System of Classification and Labelling of Chemicals (GHS), the question is whether TTIP can be any more ambitious in the area of chemicals? We find that there is no detailed or systematic knowledge about how the two levels of protection in chemicals compare, although caricatures and stereotypes abound. This is partly due to an obsessive focus on a single US federal law, the Toxic Subtances Control Act (TSCA), whereas in practice US protection depends on many statutes and regulations, as well as on voluntary withdrawals (under pressure from the Environmental Protection Agency) and severe common law liability. This paper makes the economic case for firmly addressing the regulatory barriers, discusses the EU’s proposals, finds that the European Parliament’s Resolution on TTIP of July 2015 lacks a rationale (for chemicals), argues that both TSCA and REACH ought to be improved (based on ‘better regulation’), discusses the link with a global regime, advocates significant improvement of market access where equivalence of health and environmental objectives is agreed and, finally, proposes to lower the costs for companies selling in both markets by allowing them to opt into the other party’s more stringent rules, thereby avoiding duplication while racing-to-the-top. The ‘living agreement’ on chemicals ought to be led by a new TTIP institution authorised to establish the level of health and environmental protection on both sides of the Atlantic for substances regulated on both sides. These findings will lay the foundation for a highly beneficial lowering of trading costs without in any way affecting the level of protection. Indeed, this is exactly what TTIP is, or should be, all about.This paper is the 10th in a series produced in the context of the “TTIP in the Balance” project, jointly organised by CEPS and the Center for Transatlantic Relations (CTR) in Washington, D.C. It is published simultaneously on the CEPS (www.ceps.eu) and CTR websites (http://transatlantic.sais-jhu.edu).

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Texas State Department of Highways and Public Transportation, Transportation Planning Division, Austin

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The aging process causes changes in the elderly’s sleep/awake standard impairing their cognitive abilities, particularly executive functioning, which already suffers loss by aging. The literature suggests that executive function and preserved sleep quality are key to maintaining good quality of life and independence of older people, requiring interventions to minimize the impact of losses incurred by the aging process. This study evaluated the effect of a cognitive training program and sleep hygiene techniques for executive functions and sleep quality in healthy older people. The participants were 41 healthy older adults, of both sexes, who were randomly divided into four groups: control group [GC], cognitive training group [GTC], sleep hygiene group [GHS] and training group + hygiene [GTH]. The research was developed in three stages: 1st - initial assessment of cognition and sleep; 2nd - specific intervention to each group; 3rd - post-intervention revaluation. The results showed that GTC had significant improvements in cognitive tasks flexibility, planning, verbal fluency and some aspects of episodic memory, besides gains in sleep quality and decrease on daytime hypersomnolence. The GHS improved sleep quality and daytime sleepiness as well and had significant improvements in insights capacity, planning, attention and in all evaluated aspects of episodic memory. The GTH had significant gains in cognitive flexibility, problem solving, verbal fluency, attention and episodic memory. The CG showed significant worsening in excessive daytime sleepiness in capacity planning. Thus, we conclude that cognitive training interventions and sleep hygiene strategies are useful in improving cognitive performance and quality of healthy elderly sleep.