997 resultados para Müller, Herta
Resumo:
Aerobic metabolism changes rapidly to glycolysis post-mortem resulting in a pH-decrease during the transformation of muscle in to meat affecting ligand binding and redox potential of the heme iron in myoglobin, the meat pigment. The inorganic chemistry of meat involves (i) redox-cycling between iron(II), iron(III), and iron(IV)/protein radicals; (ii) ligand exchange processes; and (iii) spin-equilibra with a change in coordination number for the heme iron. In addition to the function of myoglobin for oxygen storage, new physiological roles of myoglobin are currently being discovered, which notably find close parallels in the processes in fresh meat and nitrite-cured meat products. Myoglobin may be characterized as a bioreactor for small molecules like O2, NO, CO, CO2, H2O, and HNO with importance in bio-regulation and in protection against oxidative stress in vivo otherwise affecting lipids in membranes. Many of these processes may be recognised as colour changes in fresh meat and cured meat products under different atmospheric conditions, and could also be instructive for teaching purposes.
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OBJECTIVE: To screen for mutations in AMH and AMHR2 genes in patients with persistent Müllerian duct syndrome (PMDS). PATIENTS AND METHOD: Genomic DNA of eight patients with PMDS was obtained from peripheral blood leukocytes. Directed sequencing of the coding regions and the exon-intron boundaries of AMH and AMHR2 were performed. RESULTS: The AMH mutations p.Arg95*, p.Arg123Trp, c.556-2A>G, and p.Arg502Leu were identified in five patients; and p.Gly323Ser and p.Arg407* in AMHR2 of two individuals. In silico analyses of the novel c.556-2A>G, p.Arg502Leu and p.Arg407* mutations predicted that they were harmful and were possible causes of the disease. CONCLUSION: A likely molecular etiology was found in the eight evaluated patients with PMDS. Four mutations in AMH and two in AMHR2 were identified. Three of them are novel mutations, c.556-2A>G, and p.Arg502Leu in AMH; and p.Gly323Ser in AMHR2. Arq Bras Endocrinol Metab. 2012;56(8):473-8
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In this paper, space adaptivity is introduced to control the error in the numerical solution of hyperbolic systems of conservation laws. The reference numerical scheme is a new version of the discontinuous Galerkin method, which uses an implicit diffusive term in the direction of the streamlines, for stability purposes. The decision whether to refine or to unrefine the grid in a certain location is taken according to the magnitude of wavelet coefficients, which are indicators of local smoothness of the numerical solution. Numerical solutions of the nonlinear Euler equations illustrate the efficiency of the method. © Springer 2005.
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O objetivo deste artigo é discutir a evolução da mortalidade por câncer de colo de útero no Estado do Paraná entre 1980 e 2000 e analisar seus diferenciais socioeconômicos em cada região. Taxas de mortalidade ajustadas por idade foram calculadas para as 22 regionais de saúde do Estado a cada ano. Análises comparativas avaliaram indicadores socioeconômicos associados com regiões que apresentaram tendência estacionária e crescente de mortalidade. A mortalidade por câncer de colo uterino cresceu no Estado como um todo a uma taxa de 1,68% (IC 1,20-2,17) ao ano. A maior parte das regiões apresentou tendência estacionária de mortalidade por câncer de colo de útero. As regionais com tendência de aumento na mortalidade apresentaram proporção significativamente mais elevada de analfabetismo (p<0,001) e de adultos (15 anos ou mais) com menos de 4 anos de estudo (p=0,001), e renda per capita (p=0,025) e IDH (p=0,023) inferiores. Houve tendência de aumento na mortalidade em todo o Estado; as regiões que contribuíram para o aumento experimentaram piores indicadores socioeconômicos.
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Neste trabalho estudou-se a influência dos padrões de onda extratropicais, que favorecem o desenvolvimento de eventos extremos frios no sudeste Sul-Americano, e em particular na região conhecida como Pampa Úmida. O aquecimento anômalo observado na região do oceano Pacífico tropical ocidental a nordeste da Austrália, durante os invernos de máxima freqüência de ocorrência de Geadas Generalizadas (GG) no centro-leste da Argentina, (região conhecida como Pampa Úmida - PU), atua como disparador de ondas de Rossby, as quais se propagam até o continente, favorecendo assim a ocorrência daqueles eventos. O padrão de propagação obtido nas simulações numéricas com um modelo baroclínico global, mostra o predomínio de um número de onda 3. Adicionalmente, foram analisadas as correlações do vento meridional em altos e baixos níveis observados para os eventos de GG, selecionados dentro dos invernos de máxima freqüência de ocorrência desses eventos. O vento meridional global em 250hPa apresenta regiões com correlação estatisticamente significativa com o vento meridional médio na PU. A configuração obtida no caso do vento meridional global em 250hPa, correlacionado com o vento meridional na PU, pode estar associada ao padrão de propagação das ondas simuladas numericamente a partir da forçante tropical. Igualmente importantes e significativos são os valores de correlação do vento sul nos baixos níveis, em particular para toda região da PU. O padrão de ondas simulado está bem representado pelas significativas correlações entre o vento meridional hemisférico em altos níveis e a temperatura no dia de evento de GG.
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The dorsal raphe nucleus (DRN) is the origin of ascending serotonergic projections and is considered to be an important component of the brain circuit that mediates anxiety- and depression-related behaviors. A large fraction of DRN serotonin-positive neurons contain nitric oxide (NO). Disruption of NO-mediated neurotransmission in the DRN by NO synthase inhibitors produces anxiolytic- and antidepressant-like effects in rats and also induces nonspecific interference with locomotor activity. We investigated the involvement of the 5-HT1A autoreceptor in the locomotor effects induced by NO in the DRN of male Wistar rats (280-310 g, N = 9-10 per group). The NO donor 3-morpholinosylnomine hydrochloride (SIN-1, 150, and 300 nmol) and the NO scavenger S-3-carboxy-4-hydroxyphenylglycine (carboxy-PTIO, 0.1-3.0 nmol) were injected into the DRN of rats immediately before they were exposed to the open field for 10 min. To evaluate the involvement of the 5-HT1A receptor and the N-methyl-D-aspartate (NMDA) glutamate receptor in the locomotor effects of NO, animals were pretreated with the 5-HT1A receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT, 8 nmol), the 5-HT1A receptor antagonist N-(2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl)-N-2-pyridinyl-cyclohexanecarboxamide maleate (WAY-100635, 0.37 nmol), and the NMDA receptor antagonist DL-2-amino-7-phosphonoheptanoic acid (AP7, 1 nmol), followed by microinjection of SIN-1 into the DRN. SIN-1 increased the distance traveled (mean ± SEM) in the open-field test (4431 ± 306.1 cm; F7,63 = 2.44, P = 0.028) and this effect was blocked by previous 8-OH-DPAT (2885 ± 490.4 cm) or AP7 (3335 ± 283.5 cm) administration (P < 0.05, Duncan test). These results indicate that 5-HT1A receptor activation and/or facilitation of glutamate neurotransmission can modulate the locomotor effects induced by NO in the DRN.
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Chlamydophila abortus é o agente etiológico do aborto epizoótico bovino, cujas manifestações clínicas mais freqüentes são aborto, nascimento de bezerros prematuros e de animais fracos, natimorto e repetição de cio em intervalos irregulares. O objetivo deste trabalho foi estimar a prevalência de anticorpos anti-Chlamydophila spp. em fêmeas bovinas de propriedades rurais com histórico de aborto, selecionadas dentro do delineamento amostral do Plano Nacional de Controle e Erradicação da Brucelose e Tuberculose no estado do Paraná. Foram testadas pela prova de fixação de complemento 3.102 amostras de soro de fêmeas bovinas (idade > 24 meses), provenientes de 373 propriedades. Ao total, 44 (1,42%) animais foram positivos com títulos > 32. A prevalência de focos foi de 8,82% (6,15%-12,17%). Animais confinados ou semi-confinados (OR=3.339, P=0.004), propriedade com menos de 35 matrizes (OR=3.339, P=0.017), presença de produtos do aborto na pastagem (OR=2.372, P=0.037) e aluguel de pasto (OR=3.398, P=0.006) foram considerados fatores de risco para Chlamydophila spp. A infecção por Chlamydophila spp. acometeu um número pequeno de animais, oriundos de propriedades com histórico de aborto. A importância deste agente como causa de aborto em bovinos no estado do Paraná, se existir, é muito pequena.
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Realizou-se um estudo para caracterizar a situação epidemiológica da brucelose bovina no Estado do Paraná. O Estado foi estratificado em sete circuitos produtores ou regiões. Em cada circuito foram amostradas aleatoriamente cerca de 300 propriedades e, dentro dessas, foi escolhido de forma aleatória um número pré-estabelecido de animais, dos quais foi obtida uma amostra de sangue. No total, foram amostrados 14.857 animais, provenientes de 2.098 propriedades. Em cada propriedade amostrada foi aplicado um questionário epidemiológico para verificar o tipo de exploração e as práticas zootécnicas e sanitárias que poderiam estar associadas ao risco de infecção pela doença. O protocolo de testes utilizado foi o da triagem com o teste do antígeno acidificado tamponado e o reteste dos positivos com o teste do 2-mercaptoetanol. O rebanho foi considerado positivo se pelo menos um animal foi reagente às duas provas sorológicas. Para o Estado, os resultados de prevalências de focos e de animais infectados foram, respectivamente, de 4,0% [3,2-4,8%] e 1,7% [1,1-2,4%]. Para os circuitos, a prevalência de focos e a de animais foram, respectivamente: circuito 1, 14,7% [10,9-19,2%] e 2,8% [1,2-4,4%]; circuito 2, 8,8% [5,9-12,6%] e 2,4% [1,0-3,8%]; circuito 3, 3,4% [1,6-6,1%] e 0,85% [0,21-1,5%]; circuito 4, 2,3% [0,94-4,8%] e 0,83% [0,02-1,6%]; circuito 5, 2,3% [0,94-4,7%] e 1,6% [0,06-3,3%]; circuito 6, 0,3% [0-1,9%] e 0,09% [0-0,27%]; circuito 7, 1,0% [0,21-2,9%] e 2,2% [0-6,0%]. Os fatores de risco (odds ratio, OR) associados à condição de foco foram: compra de reprodutores (OR= 2,20 [1,42-3,40]) e prática de aluguel de pasto (OR= 2,45 [1,54-3,90]).
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The diffusion of Pollution Prevention faces organizational barriers as for instance resistance to change, insufficient support from decision-makers, unclear project leadership, insufficient employee accountability and inflexible organizational structures. To understand how to overcome such barriers, the performance of a Pollution Prevention program of a multinational corporation is analyzed. The quantitative analyses of 2096 Pollution Prevention projects conducted between 1995 and 2007 support the conclusion that the performance of the Pollution Prevention program increased after the implementation of the Six Sigma program. Moreover, the analyses of 1906 Pollution Prevention projects and 31,133 Six Sigma projects for cost reduction in 27 countries indicate that in countries where the implementation of Six Sigma is more expressive, pollution is prevented more than in countries with less expressive Six Sigma implementation. In fact, the Six Sigma implementation improved the organizational capability for data based project management. Therefore, comparing six years before and six years after the Six Sigma implementation, the total number of Pollution Prevention projects recognized increased 6.9 times and the total amount of pollution prevented increased by 62%. The qualitative analysis describes how the Six Sigma program interacts with the Pollution Prevention program in the studied company. (C) 2009 Elsevier Ltd. All rights reserved.
Resumo:
Nine samples of butter from producers in various states of Australia were analysed for polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Detectable concentrations of 2,3,7,8-chlorine substituted PCDD/Fs were found in all samples. The mean PCDD/F concentration expressed as 2',3,7,8-TCDD equivalents (TEQs) was 0.19 pg TEQ g(-1) fat. The highest concentration (0.46 pg TEQ g(-1) fat) was observable in a sample from Victoria which is the most densely populated state. Overall the results indicate that PCDD/F concentrations in dairy products from Australia are low in comparison to the levels in dairy products of industrialized countries on the Northern Hemisphere. As expected, this study provides evidence that the environmental and consequently the human body burden of PCDD/ Fs to be relatively low in Australia.
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A range of organohalogen compounds (10 polychlorinated biphenyl [PCB] congeners, DDT and metabolites, chlordane-related compounds, the potential natural organochlorine compound Q1, toxaphene, hexachlorobenzene, hexachlorocyclohexanes, dieldrin, and several yet unidentified brominated compounds) were detected in the blubber of four bottlenose dolphins (Tursiops truncatus), one common dolphin (Delphinus delphis), and seven dugongs (Dugong dugon), as well as in adipose tissue of a green turtle (Chelonia mydas) and a python (Morelia spilota) from northeast Queensland (Australia). The green turtle and dugongs accumulated lower organohalogen levels than the dolphins. Lower levels in dugongs were expected because this species is exclusively herbivorous. Highest PCB and DDT levels recorded in dugongs were 209 and 173 mug/kg lipids, respectively. Levels of the nonanthropogenic heptachlorinated compound Q1 (highest level in dugongs was 160 mug/kg lipids) were estimated using the ECD response factor of trans-nonachlor. Highest organohalogen levels were found in blubber of dolphins for sumDDT (575-52,500 mug/kg) and PCBs (600-25,500 mug/kg lipids). Furthermore, Q1 was a major organohalogen detected in all samples analyzed, ranging from 450 -9,100 mug/kg lipids. The highest concentration of Q1 determined in this study represents the highest concentration reported to date in an environmental sample. Levels of chlordane-related compounds were also high (280-7,700 mug/kg, mainly derived from trans-nonachlor), but concentrations of hexachlorobenzene, hexachlorocyclohexanes, dieldrin, and toxaphene were relatively low and contributed little to the overall organohalogen contamination. Furthermore, a series of three major (BC-1, BC-2, and BC-3) and six minor (BC-4 through BC-9) unknown brominated compounds were observable by extracting m/z 79 and m/z 81 from the GC/ECNI-MS full scan run. Structural proposals were made for the two major recalcitrant compounds (referred to as BC-1 and BC-2). BC-2 appears to be a tetrabromo-methoxy-diphenylether (512 u) and BC-1 has 14 u (corresponding with an additional CH2 group) more relative to BC-1. In general the organohalogen pattern observed in blubber of dolphins was different compared to similar samples from other locations in the world, which is apparent from the fact that the four major abundant signals in the GC/ECD chromatogram. of D. delphis originated from the four unknown compounds Q1, BC-1, BC-2, and BC-3.
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Recent investigations have demonstrated the presence of an unidentified source of polychlorinated dibenzo-p-dioxins (PCDDs) in the coastal zone of Queensland (Australia). The present study provides new information on the possible PCDD sources and their temporal input to this environment. Two estuarine sediment cores were collected in northern Queensland for which radiochemical chronologies were established. Core sections from different depositional ages, up to three centuries, have been analyzed for 2,3,7,8-substituted PCDDs and polychlorinated dibenzofurans (PCDFs). Variations of PCDD concentrations in the sediment cores over several centuries of depositional history were relatively small, and elevated PCDD levels were still present in sediment slices from the early 17th century. PCDD/F isomer patterns and congener profiles in sediments deposited during the last 350 years were almost identical and correlated well to the characteristic profiles observed in surface sediments and soils from the entire Queensland coastline. Profiles were dominated by higher chlorinated PCDDs, in particular octachlorodibenzodioxin (OCDD), whereas PCDF concentrations were below or near the limit of detection. These results indicate the presence of a PCDD source prior to industrialization and production of commercial organochlorine products. Further, the present study demonstrates that PCDD input patterns have been similar along an extensive but localized area over at least several centuries, contributing relatively high concentrations of PCDDs to the coastal system of Queensland.
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The concentrations of SOCs in leaves of an evergreen Australian native tree (Melaleuca leucadendra) and grass collected in Brisbane, Australia were determined. The concentrations of PCDD/Fs and PAHs in the leaf tissue were comparable to those reported for urbanised areas in other industrialised countries. A distinct difference in the compound profiles between the leaves of the two species was observed, with higher concentrations of the lower molecular mass PAHs and PCDD/Fs and lower concentrations of the higher molecular mass PAHs and PCDD/Fs in the Melaleuca leaves relative to the grass leaves. The interspecies differences are explained on the basis of the larger size of the lipophilic compartment (for compounds with low K-OA) and the lower ratio of surface area to volume in the Melaleuca leaves. (C) 2001 Elsevier Science Ltd. All rights reserved.
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Polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) concentrations were measured in sediment and seagrass from five locations in or adjacent to the Great Barrier Reef Marine Park. A full spectrum of Cl(5-8)DDs were present in all samples and, in particular, elevated levels of Cl8DD were found. PCDFs could not be quantified in any samples. The PCDD concentrations ranged over two orders of magnitude between sites, and there was a good correlation between sediment and seagrass levels. There were large quantities of sediment present on the seagrass (20-62% on a dry wt. basis), and it was concluded that this was a primary source of the PCDDs in the seagrass samples. The PCDD levels in the seagrass samples were compared with the levels in the tissue of three dugongs stranded in the same region. The relative accumulation of the 2,3,7,8-substituted PCDD congeners in the dugongs decreased by over two orders of magnitude with increasing degree of chlorination. This was attributed to the reduced absorption of the higher chlorinated congeners in the digestive tract, a behaviour that has been observed in other mammals such as domestic cows. (C) 2001 Elsevier Science Ltd. All rights reserved.