414 resultados para Heams, Stacey


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Many marine ecosystems have the capacity for long-term storage of organic carbon (C) in what are termed "blue carbon" systems. While blue carbon systems (saltmarsh, mangrove, and seagrass) are efficient at long-term sequestration of organic carbon (C), much of their sequestered C may originate from other (allochthonous) habitats. Macroalgae, due to their high rates of production, fragmentation, and ability to be transported, would also appear to be able to make a significant contribution as C donors to blue C habitats. In order to assess the stability of macroalgal tissues and their likely contribution to long-term pools of C, we applied thermogravimetric analysis (TGA) to 14 taxa of marine macroalgae and coastal vascular plants. We assessed the structural complexity of multiple lineages of plant and tissue types with differing cell wall structures and found that decomposition dynamics varied significantly according to differences in cell wall structure and composition among taxonomic groups and tissue function (photosynthetic vs. attachment). Vascular plant tissues generally exhibited greater stability with a greater proportion of mass loss at temperatures > 300 degrees C (peak mass loss -320 degrees C) than macroalgae (peak mass loss between 175-300 degrees C), consistent with the lignocellulose matrix of vascular plants. Greater variation in thermogravimetric signatures within and among macroalgal taxa, relative to vascular plants, was also consistent with the diversity of cell wall structure and composition among groups. Significant degradation above 600 degrees C for some macroalgae, as well as some belowground seagrass tissues, is likely due to the presence of taxon-specific compounds. The results of this study highlight the importance of the lignocellulose matrix to the stability of vascular plant sources and the potentially significant role of refractory, taxon-specific compounds (carbonates, long-chain lipids, alginates, xylans, and sulfated polysaccharides) from macroalgae and seagrasses for their long-term sedimentary C storage. This study shows that marine macroalgae do contain refractory compounds and thus may be more valuable to long-term carbon sequestration than we previously have considered.

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To understand the biology and evolution of ruminants, the cattle genome was sequenced to about sevenfold coverage. The cattle genome contains a minimum of 22,000 genes, with a core set of 14,345 orthologs shared among seven mammalian species of which 1217 are absent or undetected in noneutherian (marsupial or monotreme) genomes. Cattle-specific evolutionary breakpoint regions in chromosomes have a higher density of segmental duplications, enrichment of repetitive elements, and species-specific variations in genes associated with lactation and immune responsiveness. Genes involved in metabolism are generally highly conserved, although five metabolic genes are deleted or extensively diverged from their human orthologs. The cattle genome sequence thus provides a resource for understanding mammalian evolution and accelerating livestock genetic improvement for milk and meat production.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Syftet med denna uppsats var att beskriva vad som låg i fokus i ungdomars diskussioner, på ett webbaserat community, kring självskadebeteende. Urvalet blev 114 ungdomar mellan 13 och 25 år på communityt Helgon.net. Frågeställningarna var: ”Vilka huvudteman ligger i fokus i ungdomarnas diskussioner?”, ”Fungerar diskussionerna på forumen som ett socialt stöd?” och ”Vilka erfarenheter har ungdomarna av professionell hjälp?” Den metod som användes var en kvalitativ analys av de fyra huvudtemana ”Självskadetrend”, ”Varför skada sig själv”, ”Sårskador, ärr och skamkänslor” och ”Behandling och stöd”, som skapades utifrån vad som låg i fokus i ungdomarnas diskussioner. Enligt Alderman, Ahmed och Stacey är självskadebeteende ett sätt att hantera känslomässigt svåra situationer och att därigenom återställa den inre balansen, alltså en slags överlevnadsstrategi. Studien visar att diskussionerna på forumen fungerat som ett socialt stöd för ungdomarna, där de har kunnat ta del av varandras erfarenheter, information och tips. De flesta ungdomar hade negativa erfarenheter av professionell hjälp eftersom de bland annat kände sig felaktigt bemötta. Studien har även visat att flera ungdomar tycker att det är lättare att skriva om sin problematik till andra på Internet än att berätta om det till professionella. Uppsatsförfattarnas idé utifrån detta har varit att det vore lämpligt om de professionella använde sig mer av Internet för att kunna nå ut till ungdomarna. Detta skulle i sin tur ge en möjlighet till att arbeta mer förebyggande och fånga upp de ungdomar som ligger i riskzonen.

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Recent research with several species of nonhuman primates suggests sophisticated motor-planning abilities observed in human adults may be ubiquitous among primates. However, there is considerable variability in the extent to which these abilities are expressed across primate species. In the present experiment, we explore whether the variability in the expression of anticipatory motor-planning abilities may be attributed to cognitive differences (such as tool use abilities) or whether they may be due to the consequences of morphological differences (such as being able to deploy a precision grasp). We compared two species of New World monkeys that differ in their tool use abilities and manual dexterity: squirrel monkeys, Saimiri sciureus (less dexterous with little evidence for tool use) and tufted capuchins, Sapajus apella (more dexterous and known tool users). The monkeys were presented with baited cups in an untrained food extraction task. Consistent with the morphological constraint hypothesis, squirrel monkeys frequently showed second-order motor planning by inverting their grasp when picking up an inverted cup, while capuchins frequently deployed canonical upright grasping postures. Findings suggest that the lack of ability for precision grasping may elicit more consistent second-order motor planning, as the squirrel monkeys (and other species that have shown a high rate of second-order planning) have fewer means of compensating for inefficient initial postures. Thus, the interface between morphology and motor planning likely represents an important factor for understanding both the ontogenetic and phylogenetic origins of sophisticated motor-planning abilities.

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Recent research with several species of nonhuman primates suggests sophisticated motor-planning abilities observed in human adults may be ubiquitous among primates. However, there is considerable variability in the extent to which these abilities are expressed across primate species. In the present experiment, we explore whether the variability in the expression of anticipatory motor-planning abilities may be attributed to cognitive differences (such as tool use abilities) or whether they may be due to the consequences of morphological differences (such as being able to deploy a precision grasp). We compared two species of New World monkeys that differ in their tool use abilities and manual dexterity: squirrel monkeys, Saimiri sciureus (less dexterous with little evidence for tool use) and tufted capuchins, Sapajus apella (more dexterous and known tool users). The monkeys were presented with baited cups in an untrained food extraction task. Consistent with the morphological constraint hypothesis, squirrel monkeys frequently showed second-order motor planning by inverting their grasp when picking up an inverted cup, while capuchins frequently deployed canonical upright grasping postures. Findings suggest that the lack of ability for precision grasping may elicit more consistent second-order motor planning, as the squirrel monkeys (and other species that have shown a high rate of second-order planning) have fewer means of compensating for inefficient initial postures. Thus, the interface between morphology and motor planning likely represents an important factor for understanding both the ontogenetic and phylogenetic origins of sophisticated motor-planning abilities. (C) 2013 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

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More than 1,000 susceptibility loci have been identified through genome-wide association studies (GWAS) of common variants; however, the specific genes and full allelic spectrum of causal variants underlying these findings have not yet been defined. Here we used pooled next-generation sequencing to study 56 genes from regions associated with Crohn's disease in 350 cases and 350 controls. Through follow-up genotyping of 70 rare and low-frequency protein-altering variants in nine independent case-control series (16,054 Crohn's disease cases, 12,153 ulcerative colitis cases and 17,575 healthy controls), we identified four additional independent risk factors in NOD2, two additional protective variants in IL23R, a highly significant association with a protective splice variant in CARD9 (P < 1 × 10(-16), odds ratio ≈ 0.29) and additional associations with coding variants in IL18RAP, CUL2, C1orf106, PTPN22 and MUC19. We extend the results of successful GWAS by identifying new, rare and probably functional variants that could aid functional experiments and predictive models.

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Multiple recent studies provide evidence that both human and nonhuman primates possess motor planning abilities. I tested for the demonstration of motor planning in two previously untested primate species through two experiments. In the first experiment, I compared the extent to which squirrel monkeys (Saimiri sciureus) and brown capuchins (Cebus apella) plan their movements in a grasping task. Individuals were presented with an inverted cup that required being turned and held upright in order to extract a food reward from the inside of the cup. This task was most efficiently solved by using an initially awkward inverted grasp that affords a comfortable hand and arm orientation at the end of the movement (known as end-state comfort). While certain individuals from both species exhibited end-state comfort, many of the capuchins never demonstrated this type of motor planning. Furthermore, the squirrel monkeys used the efficient grasp significantly more than the capuchins. In the second experiment, I presented the capuchins with another grasping task to test if they would express motor planning abilities in a different context. Here, the capuchins were offered a dowel that was baited on either the left or right end. A radial grasp with the thumb pointing towards the baited end was considered to be the most efficient grasp because it afforded a comfortable final position. The capuchins switched hands and used an overhand radial grasp on the dowel significantly more often than not, thus demonstrating motor planning in this task. The grasps typically utilized by these two closely related species differ considerably in that capuchins are capable of exercising precision grips, whereas squirrel monkeys are limited to whole-handed power grips. Moreover, unlike capuchins, squirrel monkeys are not particularly dexterous nor are they capable of precise manipulative actions. It is therefore more beneficial for squirrel monkeys to plan their movements efficiently because they are less capable of compensating for inappropriate initial grasps. Due to the appreciable variability in the expression of motor planning skills across species, I proposed that morphological constraints might explain the observed discrepancies in movement planning among different primate species.

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Chronic graft-versus-host disease (cGVHD), a common complication after stem cell transplant (SCT), has an impact on morbidity and survival. Previous classification of cGVHD has not been reproducible or prognostic for nonrelapse mortality (NRM). Recently the National Institutes of Health (NIH) consensus criteria were proposed, but the ability of this classification to predict outcome of various subtypes of cGVHD is unknown. Patients (N = 110) undergoing an SCT for a hematologic malignancy and surviving until day 100 posttransplant from 2001 to 2003 were studied. The overall survival (OS) using a landmark analysis at day 100 was 44% versus 66% (no GVHD vs. GVHD, P = .026). The OS of patients with various types of GVHD as proposed by the NIH criteria were significantly different (P < .0001). In a univariate analyses, this was more apparent when patients with any acute features of GVHD were compared to classic cGVHD (3-year OS 46% vs. 68%, P = .033). The 3-year NRM for the entire cohort was 21%, and was not affected by presence or absence of GVHD or subtypes of GVHD. In a multivariable analysis, extensive cGVHD (hazard ratio [HR] 0.35, P = .015) and having any acute feature of GVHD after day 100 (HR 3.36, P = .0144) were significant independent predictors of survival. The OS with different NIH subtypes of GVHD after day 100 from SCT varies, and is superior for patients with classic cGVHD.

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Between January 1990 and April 2001, 115 patients received high-dose chemotherapy (HDT) followed by autologous stem cell transplantation (ASCT) for relapsed or refractory Hodgkin lymphoma (HL). With a median follow-up of 58 months (range, 1 - 175 months), 5-year progression-free survival (PFS) and overall survival (OS) were 46% and 58%, respectively. Twelve patients with primary refractory disease had a 5-year PFS of 41% and OS of 58%, not significantly different from those of the remaining cohort. Early and overall regimen related mortality were 7% and 16%, respectively. Male gender (P = 0.04) and a time to relapse (TTR) < 12 months (P = 0.03) were associated with decreased OS by univariate analysis. In multivariate analysis, TTR < 12 months remained statistically significant (P = 0.04). We have confirmed that HDT and ASCT result in long-term survival for a proportion of patients with relapsed or refractory HL. All patients, including those with primary refractory disease, benefited from HDT and ASCT.

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This methods paper outlines the overall design of a community-based multidisciplinary longitudinal study with the intent to stimulate interest and communication from scientists and practitioners studying the role of physical activity in preventive medicine. In adults, lack of regular exercise is a major risk factor in the development of chronic degenerative diseases and is a major contributor to obesity, and now we have evidence that many of our children are not sufficiently active to prevent early symptoms of chronic disease. The lifestyle of our kids (LOOK) study investigates how early physical activity contributes to health and development, utilizing a longitudinal design and a cohort of eight hundred and thirty 7-8-year-old (grade 2) school children followed to age 11-12 years (grade 6), their average family income being very close to that of Australia. We will test two hypotheses, that (a) the quantity and quality of physical activity undertaken by primary school children will influence their psychological and physical health and development; (b) compared with existing practices in primary schools, a physical education program administered by visiting specialists will enhance health and development, and lead to a more positive perception of physical activity. To test the first hypothesis we will monitor all children longitudinally over the 4 years. To test the second we will involve an intervention group of 430 children who receive two 50min physical education classes every week from visiting specialists and a control group of 400 who continue with their usual primary school physical education with their class-room teachers. At the end of grades 2, 4, and 6 we will measure several areas of health and development including blood risk factors for chronic disease, cardiovascular structure and function, physical fitness, psychological characteristics and perceptions of physical activity, bone structure and strength, motor control, body composition, nutritional intake, influence of teachers and family, and academic performance.

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The National Institutes of Health (NIH) classification of graft-versus-host disease (GVHD) is a significant improvement over prior classifications, and has prognostic implications. We hypothesized that the NIH classification of GVHD would predict the survival of patients with GVHD treated with extracorporeal photopheresis (ECP). Sixty-four patients with steroid refractory/dependent GVHD treated with ECP were studied. The 3-year overall survival (OS) was 36% (95% confidence interval [CI] 13-59). Progressive GVHD was seen in 39% of patients with any acute GVHD (aGVHD) (classic acute, recurrent acute, overlap) compared to 3% of patients with classic chronic GVHD (cGVHD) (P=.002). OS was superior for patients with classic cGVHD (median survival, not reached) compared to overlap GVHD (median survival, 395 days, 95% CI 101 to not reached) and aGVHD (delayed, recurrent or persistent) (median survival, 72 days, 95% CI 39-152). In univariate analyses, significant predictors of survival after ECP included GVHD subtype, bilirubin, platelet count, and steroid dose. In multivariate analyses overlap plus classic cGVHD was an independent prognostic feature predictive of superior survival (hazard ratio [HR] 0.34, 95% CI 0.14-0.8, p=.014). This study suggests that NIH classification can predict outcome after ECP for steroid refractory/dependent GVHD.