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1.
Nature ; 601(7892): 263-267, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34937938

RESUMO

Cancer is a ubiquitous disease of metazoans, predicted to disproportionately affect larger, long-lived organisms owing to their greater number of cell divisions, and thus increased probability of somatic mutations1,2. While elevated cancer risk with larger body size and/or longevity has been documented within species3-5, Peto's paradox indicates the apparent lack of such an association among taxa6. Yet, unequivocal empirical evidence for Peto's paradox is lacking, stemming from the difficulty of estimating cancer risk in non-model species. Here we build and analyse a database on cancer-related mortality using data on adult zoo mammals (110,148 individuals, 191 species) and map age-controlled cancer mortality to the mammalian tree of life. We demonstrate the universality and high frequency of oncogenic phenomena in mammals and reveal substantial differences in cancer mortality across major mammalian orders. We show that the phylogenetic distribution of cancer mortality is associated with diet, with carnivorous mammals (especially mammal-consuming ones) facing the highest cancer-related mortality. Moreover, we provide unequivocal evidence for the body size and longevity components of Peto's paradox by showing that cancer mortality risk is largely independent of both body mass and adult life expectancy across species. These results highlight the key role of life-history evolution in shaping cancer resistance and provide major advancements in the quest for natural anticancer defences.


Assuntos
Animais de Zoológico , Dieta , Mamíferos , Neoplasias , Envelhecimento , Animais , Animais de Zoológico/classificação , Tamanho Corporal , Peso Corporal , Carnivoridade , Dieta/veterinária , Longevidade , Mamíferos/classificação , Neoplasias/mortalidade , Neoplasias/patologia , Neoplasias/veterinária , Filogenia , Fatores de Risco , Especificidade da Espécie
2.
Mol Phylogenet Evol ; 163: 107214, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34052438

RESUMO

Introgression and hybridization are important processes in plant evolution, but they are difficult to study from a phylogenetic perspective, because they conflict with the bifurcating evolutionary history typically depicted in phylogenetic models. The role of hybridization in plant evolution is best documented in the form of allo-polyploidizations. In contrast, homoploid hybridization and introgression are less explored, although they may be crucial in adaptive radiations. Here we employ genome-wide data (ddRAD-seq, transcriptomes) to investigate the evolutionary history of Nepenthes, a radiation of c. 160 species of iconic carnivorous plants mainly from tropical Asia. Our data indicates that the main radiation is only c. 5 million years old, and confirms previous bifurcating phylogenies. However, due to a greatly expanded number of loci, we were able test for the first time the long-standing hypotheses of introgression and historical hybridization. The genus presents one very clear case of organellar capture between two distantly related but sympatric groups. Furthermore, all Nepenthes species show introgression signals in their nuclear genomes, as uncovered by a general survey of ABBA-BABA-like statistics. The ancestor of the rapid main radiation shows ancestry from two deeply diverged lineages, as indicated by phylogenetic network analyses. All major clades of the main radiation show further introgression both within and between each other, as suggested by admixture graphs. Our study supports the hypothesis that rapid adaptive radiations are hotspots of introgression in the tree of life, and highlights the need to consider non-treelike processes in evolutionary studies of Nepenthes in particular.


Assuntos
Carnivoridade , Hibridização Genética , Compostos Orgânicos , Filogenia
3.
Am J Bot ; 107(9): 1253-1259, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32882073

RESUMO

PREMISE: As repeatedly shown, the remarkable variation in the genome size of angiosperms can be shaped by extrinsic selective pressures, including nutrient availability. Carnivory has evolved independently in 10 angiosperm clades, but all carnivorous plants share a common affinity to nutrient-poor habitats. As such, carnivory and genome reduction could be responses to the same environmental pressure. Indeed, the smallest genomes among flowering plants are found in the carnivorous family Lentibulariaceae, where a unique mutation in cytochrome c oxidase (COX) is suspected to promote genome miniaturization. Despite these hypotheses, a phylogenetically informed test of genome size and nutrient availability across carnivorous clades has so far been missing. METHODS: Using linear mixed models, we compared genome sizes of 127 carnivorous plants from 7 diverse angiosperm clades with 1072 of their noncarnivorous relatives. We also tested whether genome size in Lentibulariaceae reflects the presence of the COX mutation. RESULTS: The genome sizes of carnivorous plants do not differ significantly from those of their noncarnivorous relatives. Based on available data, no significant association between the COX mutation and genome miniaturization could be confirmed, not even when considering polyploidy. CONCLUSIONS: Carnivory alone does not seem to significantly affect genome size decrease. Plausibly, it might actually counterbalance the effect of nutrient limitation on genome size evolution. The role of the COX mutation in genome miniaturization needs to be evaluated by analysis of a broader data set because current knowledge of its presence across Lentibulariaceae covers less than 10% of the species diversity in this family.


Assuntos
Carnivoridade , Magnoliopsida/genética , Tamanho do Genoma , Genoma de Planta , Humanos , Filogenia , Poliploidia
4.
Acta amaz ; 50(3): 256-259, jul. - set. 2020.
Artigo em Inglês | LILACS | ID: biblio-1118852

RESUMO

The oviposition behavior of the rare butterfly Minstrellus grandis (Callaghan, 1999) (Lepidoptera: Riodinidae) is recorded for the first time. Two females laid eggs on the old leaves of an unidentified Triplaris sp. (Polygonaceae), a myrmecophytic plant typically known as 'Triplaria' or 'novice' tree, inhabited by aggressive 'taxi' ants of the genus Pseudomyrmex sp. (Hymenoptera: Formicidae). These observations suggest that M. grandis caterpillars live associated with one of the most harmful types of Amazon ant-plant symbiosis. (AU)


Assuntos
Formigas , Simbiose , Borboletas , Ecossistema Amazônico , Carnivoridade , Oviposição
5.
Fish Shellfish Immunol ; 100: 109-116, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32156583

RESUMO

The present study was conducted to explore the influence of dietary carbohydrate on antioxidant capacity and non-specific immunity of hybrid grouper, which would contribute to determine the tolerable dietary carbohydrate content. Seven diets with grade levels of carbohydrate (5.27, 8.95, 11.49, 14.37, 17.78, 20.82 and 23.65%) were fed to triplicate groups of fish for 10 weeks. Results showed that the inclusion of carbohydrate above 11.49% produced significant increased content of hydrogen peroxide (H2O2) in liver and malondialdehyde (MDA) in both serum and liver. The specific activity of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (Gpx) and total antioxidative capacity (T-AOC) were significantly elevated with the increase of dietary carbohydrate from 8.95 to 23.65%, which may be associated with the reduced hepatic soluble protein content. However, opposite variation was observed in the expression of antioxidant related genes (SOD1 and Gpx), which was partly caused by the activation of NF-E2-related factor 2 (Nrf2) and inhibition of Kelch-like-ECH-associated protein 1 (Keap1) at the transcriptional level. The immunoglobulin M (lgM) content and activity of lysozyme and CCP in serum significantly depressed when dietary carbohydrate was above 11.49%. The expression of pro-inflammatory cytokines (TNF-α, IL-1ß and IL-8) was significantly increased with the increase of dietary carbohydrate from 5.27 to 8.95% and thereafter significantly reduced, which was consistent with the changed expression of toll-like receptor 2 (TLR2) and nuclear factor κΒ (NF-κΒ). In above, high dietary carbohydrate significantly impaired the antioxidant capacity and reduced the non-specific immunity of hybrid grouper, and the tolerable dietary carbohydrate content should not exceed 11.49%.


Assuntos
Bass/imunologia , Carboidratos da Dieta/administração & dosagem , Proteínas de Peixes/imunologia , Expressão Gênica , Ração Animal , Animais , Antioxidantes/metabolismo , Bass/genética , Carnivoridade , Quimera/genética , Quimera/imunologia , Citocinas/imunologia , Suplementos Nutricionais , Feminino , Proteínas de Peixes/genética , Imunidade Inata , Masculino
6.
Sci Adv ; 5(10): eaav9822, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31633015

RESUMO

Bone marrow and grease constitute an important source of nutrition and have attracted the attention of human groups since prehistoric times. Marrow consumption has been linked to immediate consumption following the procurement and removal of soft tissues. Here, we present the earliest evidence for storage and delayed consumption of bone marrow at Qesem Cave, Israel (~420 to 200 ka). By using experimental series controlling exposure time and environmental parameters, combined with chemical analyses, we evaluated bone marrow preservation. The combination of archaeological and experimental results allowed us to isolate specific marks linked to dry skin removal and determine a low rate of marrow fat degradation of up to 9 weeks of exposure. This is the earliest evidence of such previously unidentified behavior, and it offers insights into the socio-economy of the human groups who lived at Qesem and may mark a threshold to new modes of Palaeolithic human adaptation.


Assuntos
Medula Óssea , Osso e Ossos/química , Armazenamento de Alimentos/história , Animais , Arqueologia , Medula Óssea/química , Carnivoridade , Culinária/história , Diáfises , Comportamento Alimentar , Herbivoria , História Antiga , Humanos , Israel , Pele , Tendões
7.
PLoS One ; 14(5): e0216733, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31150420

RESUMO

In archaeological assemblages the presence of percussion marks, on the surface of long bones, is an indicator of long bone marrow extraction. The form, quantity and distribution of percussion marks are analysed to gain a better understanding of the marrow extraction process. Patterns of bone percussion damage in archaeological assemblages may highlight standardized actions, possibly related to butchery traditions. However, additional factors could underlie these patterns and should also be considered. In this article we test intuitiveness as a factor in appearance of percussion mark patterns, to see if patterns can appear when bones are being fractured without prior experience with bone fracture properties. To test this hypothesis, for this study we selected a sample of 40 cattle (Bos taurus) long limb bones from a large bone breakage experiment (400 long limb bones), where participants had no previous experience in bone breakage and may thus have broken bones intuitively. We used Geographic Information System (GIS) software to analyse the distribution of percussion marks. Using ArcGIS Spatial Analysts tools, we identified and quantified significant concentrations of percussion marks. Results show that percussion mark patterns emerge for the same bone element, and that specific sides and zones were recurrently selected by experimenters. The distribution of patterns varies among the different long bone elements, and we attribute this variance to an adjustment to bone morphology. In addition, we calculated and identified bone damage patterns resulting from hammerstone percussion. Crossing bone survivorship with percussion mark patterns enabled us to recognise and evaluate the effects of fragmentation and surface visibility in controlled experimental conditions. The GIS method facilitates comparisons between different variables and provides a sophisticated visual representation of results. Enlarging the sample will allow to constitute a more substantial analogous model for fossil assemblages.


Assuntos
Medula Óssea , Fósseis/patologia , Fraturas Ósseas , Sistemas de Informação Geográfica , Matadouros , Animais , Arqueologia/métodos , Medula Óssea/anatomia & histologia , Medula Óssea/diagnóstico por imagem , Carnivoridade , Bovinos , Manipulação de Alimentos/história , Manipulação de Alimentos/métodos , Fósseis/diagnóstico por imagem , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/história , Fraturas Ósseas/patologia , História Antiga , Humanos , Modelos Anatômicos
8.
Mar Pollut Bull ; 144: 134-139, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31179979

RESUMO

The hypothesis that carnivorous consumers associated with the seabed are more likely to ingest marine debris was tested based on stomach content analysis of fish (Trichiurus lepturus and species of Ariidae) and cetaceans (Sotalia guianensis and Pontoporia blainvillei). Among 596 stomach contents, only 22 (3.7%) contained debris. The debris was flexible plastic, nylon yard, paper, latex, styrofoam and cigarette filter. The proportion of stomach contents with debris varied among species: P. blainvillei (pelagic demersal consumer) presented the highest frequency of ingestion (15.7%), while T. lepturus (pelagic consumer), S. guianensis (pelagic consumer) and Ariidae (demersal consumer) presented similar frequencies (1.3-1.8%). Therefore, a feeding site in the water column does not predict the probability of debris ingestion. Concerning these species, this probability seems to be more associated with prey-capture strategies (or feeding behavior), regardless of debris availability in the environment.


Assuntos
Carnivoridade , Golfinhos/fisiologia , Perciformes/fisiologia , Plásticos/análise , Água do Mar/química , Resíduos/análise , Poluentes Químicos da Água/análise , Animais , Brasil , Carnivoridade/fisiologia , Ingestão de Alimentos , Conteúdo Gastrointestinal/química
9.
Sci Adv ; 4(5): eaar6478, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29774238

RESUMO

The end-Cretaceous extinction led to a massive faunal turnover, with placental mammals radiating in the wake of nonavian dinosaurs. Fossils indicate that Cretaceous stem placentals were generally insectivorous, whereas their earliest Cenozoic descendants occupied a variety of dietary niches. It is hypothesized that this dietary radiation resulted from the opening of niche space, following the extinction of dinosaurian carnivores and herbivores. We provide the first genomic evidence for the occurrence and timing of this dietary radiation in placental mammals. By comparing the genomes of 107 placental mammals, we robustly infer that chitinase genes (CHIAs), encoding enzymes capable of digesting insect exoskeletal chitin, were present as five functional copies in the ancestor of all placental mammals, and the number of functional CHIAs in the genomes of extant species positively correlates with the percentage of invertebrates in their diets. The diverse repertoire of CHIAs in early placental mammals corroborates fossil evidence of insectivory in Cretaceous eutherians, with descendant lineages repeatedly losing CHIAs beginning at the Cretaceous/Paleogene (K/Pg) boundary as they radiated into noninsectivorous niches. Furthermore, the timing of gene loss suggests that interordinal diversification of placental mammals in the Cretaceous predates the dietary radiation in the early Cenozoic, helping to reconcile a long-standing debate between molecular timetrees and the fossil record. Our results demonstrate that placental mammal genomes, including humans, retain a molecular record of the post-K/Pg placental adaptive radiation in the form of numerous chitinase pseudogenes.


Assuntos
Quitinases/genética , Extinção Biológica , Fósseis , Genoma , Genômica , Mamíferos/classificação , Mamíferos/genética , Placenta , Ração Animal , Animais , Evolução Biológica , Carnivoridade , Feminino , Dosagem de Genes , Genômica/métodos , Herbivoria , Filogenia , Gravidez
10.
Behav Processes ; 145: 44-47, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28882654

RESUMO

Considering that each personality type in animals presents distinct physiological and behavioural responses, this study evaluated the efficiency of the Novel Environment test to classify larvae of Lophiosilurus alexandri into bold and shy individuals, which were then investigated for growth, cannibalism and mortality in larviculture of pure and mixed groups. Larvae with an average weight of 24.0±1.7mg and length of 14.1±0.4mm, were subjected to a Novel Environment test to classify their personality type (bold and shy larvae). After the larvae were classified according to personality type, they were subjected to larviculture for 15days. Three treatments were tested: only bold larvae, only shy larvae, and a mixed treatment (bold larvae+shy larvae) at a density for 16 larvae/L, which were fed 3 times a day with Artemia nauplii. After larviculture, there were no differences in the final lengths of larvae of the bold, shy, and mixed treatments (26.9±0.76mm, 26.7±1.00mm, and 26.8±1.24mm, respectively); however, shy larvae possessed weighed less (0.22±0.01g) than the bold and mixed treatments, which did not differ significantly (0.25±0.02g and 0.27±0.02g, respectively). The bold and mixed treatments had the highest cannibalism rate (11.2±5.1% and 23.1±12.3%, respectively). Overall survival was lowest in the mixed treatment (62.5±13.0%), while that of the bold and shy treatments were similar (82.5±9.2% and 86.2±9.2%, respectively). The separation of L. alexandri larvae by traits can ensure a decrease in cannibalism and hence, more productive larviculture.


Assuntos
Aquicultura/métodos , Carnivoridade/psicologia , Peixes-Gato/crescimento & desenvolvimento , Caráter , Larva/crescimento & desenvolvimento , Animais , Meio Ambiente , Programas de Rastreamento , Comportamento Social , Meio Social , Análise de Sobrevida
11.
Proc Natl Acad Sci U S A ; 114(22): E4435-E4441, 2017 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-28507139

RESUMO

Utricularia gibba, the humped bladderwort, is a carnivorous plant that retains a tiny nuclear genome despite at least two rounds of whole genome duplication (WGD) since common ancestry with grapevine and other species. We used a third-generation genome assembly with several complete chromosomes to reconstruct the two most recent lineage-specific ancestral genomes that led to the modern U. gibba genome structure. Patterns of subgenome dominance in the most recent WGD, both architectural and transcriptional, are suggestive of allopolyploidization, which may have generated genomic novelty and led to instantaneous speciation. Syntenic duplicates retained in polyploid blocks are enriched for transcription factor functions, whereas gene copies derived from ongoing tandem duplication events are enriched in metabolic functions potentially important for a carnivorous plant. Among these are tandem arrays of cysteine protease genes with trap-specific expression that evolved within a protein family known to be useful in the digestion of animal prey. Further enriched functions among tandem duplicates (also with trap-enhanced expression) include peptide transport (intercellular movement of broken-down prey proteins), ATPase activities (bladder-trap acidification and transmembrane nutrient transport), hydrolase and chitinase activities (breakdown of prey polysaccharides), and cell-wall dynamic components possibly associated with active bladder movements. Whereas independently polyploid Arabidopsis syntenic gene duplicates are similarly enriched for transcriptional regulatory activities, Arabidopsis tandems are distinct from those of U. gibba, while still metabolic and likely reflecting unique adaptations of that species. Taken together, these findings highlight the special importance of tandem duplications in the adaptive landscapes of a carnivorous plant genome.


Assuntos
Carnivoridade/fisiologia , Genoma de Planta , Lamiales/genética , Lamiales/fisiologia , Adaptação Fisiológica/genética , Cisteína Proteases/química , Cisteína Proteases/genética , Evolução Molecular , Duplicação Gênica , Modelos Moleculares , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Poliploidia , Análise de Sequência de DNA , Sintenia
12.
Artigo em Inglês | MEDLINE | ID: mdl-27956166

RESUMO

Tasmanian devils (Sarcophilus harrisii) are the largest carnivorous marsupial in Australia. Currently many animals are being held in captivity as a management procedure to combat Devil Facial Tumor Disease. Only one published study thus far has investigated nutrition in Tasmanian devils, determining their maintenance energy requirements and digestibility on a rodent diet. More information is needed on Tasmanian devil nutritional and gastrointestinal function to aid in their management. Our study aimed to investigate the current nutritional status of Tasmanian devils in a captive population and functional morphology and histology of their gastrointestinal tract. Animals were maintained on a diet of kangaroo, rabbit, quail and chicken wings and digestibility of these items by the devils was high (>85% for dry matter, protein and lipid). Kangaroo and rabbit were high protein diet items while the quail and chicken wings provided high lipid to the diet, and carbohydrates were minimal (≤3% energy). Maintenance energy requirements were determined to be 620kJkg-0.75d-1 with no significant difference between males and females. Opportunistic samples for gastrointestinal morphology were obtained from captive specimens. Tasmanian devils have a simple digestive tract similar to other dasyurid species. Both the morphology and histology of the gastrointestinal tract show specialization for a high protein carnivorous diet.


Assuntos
Marsupiais/fisiologia , Ração Animal/análise , Animais , Animais de Zoológico , Austrália , Carnivoridade/fisiologia , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Ingestão de Alimentos , Espécies em Perigo de Extinção , Neoplasias Faciais/veterinária , Feminino , Trato Gastrointestinal/anatomia & histologia , Trato Gastrointestinal/fisiologia , Masculino , Marsupiais/anatomia & histologia , Estado Nutricional
13.
Salud Publica Mex ; 58(2): 261-73, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27557384

RESUMO

Diet is an important modifiable risk factor for cancer. Adequate diet modification may play a key role in reducing the incidence of some cancers. A growing body of epidemiological evidence suggested links of some nutritional exposures with individual cancers. This review updates and summarises the existing data on diet related factors for cancer prevention, evaluated in 2007 by World Cancer Research Fund/American Institute for Cancer Research and identifies the areas where more research is needed. Mechanisms of action of nutrients are discussed. For cancer prevention, more apparent association pertains to the role of foods from plant origin, processed meat products and alcohol. There is a lack of evidence to clarify the relationship of dairy and cereal products, different types of carbohydrates, micronutrients naturally found in foods vs supplements, industrial trans-fats, food preparation and handling techniques and dietary patterns and cancer, in order to implement safe cancer prevention strategies.


Assuntos
Dieta , Neoplasias/etiologia , Animais , Bebidas/efeitos adversos , Carnivoridade , Culinária , Dieta/efeitos adversos , Comportamento Alimentar , Alimentos/efeitos adversos , Alimentos/classificação , Humanos , Neoplasias/epidemiologia , Neoplasias/prevenção & controle , Risco
14.
Proteins ; 84(10): 1517-33, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27353064

RESUMO

In his 1875 monograph on insectivorous plants, Darwin described the feeding reactions of Drosera flypaper traps and predicted that their secretions contained a "ferment" similar to mammalian pepsin, an aspartic protease. Here we report a high-quality draft genome sequence for the cape sundew, Drosera capensis, the first genome of a carnivorous plant from order Caryophyllales, which also includes the Venus flytrap (Dionaea) and the tropical pitcher plants (Nepenthes). This species was selected in part for its hardiness and ease of cultivation, making it an excellent model organism for further investigations of plant carnivory. Analysis of predicted protein sequences yields genes encoding proteases homologous to those found in other plants, some of which display sequence and structural features that suggest novel functionalities. Because the sequence similarity to proteins of known structure is in most cases too low for traditional homology modeling, 3D structures of representative proteases are predicted using comparative modeling with all-atom refinement. Although the overall folds and active residues for these proteins are conserved, we find structural and sequence differences consistent with a diversity of substrate recognition patterns. Finally, we predict differences in substrate specificities using in silico experiments, providing targets for structure/function studies of novel enzymes with biological and technological significance. Proteins 2016; 84:1517-1533. © 2016 Wiley Periodicals, Inc.


Assuntos
Carnivoridade/fisiologia , Drosera/genética , Droseraceae/genética , Genoma de Planta , Peptídeo Hidrolases/química , Proteínas de Plantas/química , Sequência de Aminoácidos , Domínio Catalítico , Mapeamento de Sequências Contíguas , Drosera/classificação , Droseraceae/classificação , Sequenciamento de Nucleotídeos em Larga Escala , Simulação de Acoplamento Molecular , Anotação de Sequência Molecular , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Domínios Proteicos , Dobramento de Proteína , Estrutura Secundária de Proteína , Alinhamento de Sequência , Homologia Estrutural de Proteína , Especificidade por Substrato
15.
Salud pública Méx ; 58(2): 261-273, Mar.-Apr. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-793019

RESUMO

Abstract Diet is an important modifiable risk factor for cancer. Adequate diet modification may play a key role in reducing the incidence of some cancers. A growing body of epidemiological evidence suggested links of some nutritional exposures with individual cancers. This review updates and summarises the existing data on diet related factors for cancer prevention, evaluated in 2007 by World Cancer Research Fund/American Institute for Cancer Research and identifies the areas where more research is needed. Mechanisms of action of nutrients are discussed. For cancer prevention, more apparent association pertains to the role of foods from plant origin, processed meat products and alcohol. There is a lack of evidence to clarify the relationship of dairy and cereal products, different types of carbohydrates, micronutrients naturally found in foods vs supplements, industrial trans-fats, food preparation and handling techniques and dietary patterns and cancer, in order to implement safe cancer prevention strategies.


Resumen La dieta es un factor de riesgo modificable importante para el cáncer. Una modificación adecuada puede jugar un papel clave en la reducción de la incidencia de algunos cánceres. La evidencia epidemiológica sugiere enlaces de algunas exposiciones nutricionales con cánceres específicos. Esta revisión actualiza y resume los datos existentes sobre factores de la dieta que se relacionan con la prevención del cáncer, que fueron evaluados en 2007 por el World Cancer Research Fund/American Institute for Cancer Research, e identifica áreas para profundizar en investigación. Se discuten mecanismos de acción de los nutrientes. Para la prevención del cáncer, la evidencia epidemiológica se relaciona con los alimentos de origen vegetal, carnes procesadas y alcohol. Se necesita más investigación para aclarar la relación que tienen con el cáncer ciertos alimentos como lácteos, granos, diferentes tipos de carbohidratos, y otros factores que podrían intervenir: micronutrientes presentes en los alimentos contra suplementos, grasas industriales trans, preparación de alimentos y hábitos alimentarios. Esto facilitaría la creación de estrategias seguras de prevención de cáncer.


Assuntos
Humanos , Animais , Dieta/efeitos adversos , Neoplasias/etiologia , Bebidas/efeitos adversos , Risco , Culinária , Comportamento Alimentar , Carnivoridade , Alimentos/classificação , Alimentos/efeitos adversos , Neoplasias/prevenção & controle , Neoplasias/epidemiologia
16.
Mol Phylogenet Evol ; 94(Pt A): 327-45, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26416707

RESUMO

Carnivorous sponges are characterized by their unique method of capturing mesoplanktonic prey coupled with the complete or partial reduction of the aquiferous system characteristic of the phylum Porifera. Current systematics place the vast majority of carnivorous sponges within Cladorhizidae, with certain species assigned to Guitarridae and Esperiopsidae. Morphological characters have not been able to show whether this classification is evolutionary accurate, and whether carnivory has evolved once or in several lineages. In the present paper we present the first comprehensive molecular phylogeny of the carnivorous sponges, interpret these results in conjunction with morphological characters, and propose a revised classification of the group. Molecular phylogenies were inferred using 18S rDNA and a combined dataset of partial 28S rDNA, COI and ALG11 sequences. The results recovered carnivorous sponges as a clade closely related to the families Mycalidae and Guitarridae, showing family Cladorhizidae to be monophyletic and also including carnivorous species currently placed in other families. The genus Lycopodina is resurrected for species currently placed in the paraphyletic subgenus Asbestopluma (Asbestopluma) featuring forceps spicules and lacking sigmas or sigmancistras. The genera Chondrocladia and Cladorhiza are found to be monophyletic. However, results indicate that the subgenus Chondrocladia is polyphyletic with respect to the subgenera Meliiderma and Symmetrocladia. Euchelipluma, formerly Guitarridae, is retained, but transferred to Cladorhizidae. The four known carnivorous species currently in Esperiopsis are transferred to Abyssocladia. Neocladia is a junior homonym and is here renamed Koltunicladia. Our results provide strong evidence in support of the hypothesis that carnivory in sponges has evolved only once. While spicule characters mostly reflect monophyletic groups at the generic level, differences between genera represent evolution within family Cladorhizidae rather than evolution of carnivory in separate lineages. Conflicting spicule characters can be reinterpreted to support the inclusion of all carnivorous sponges within Cladorhizidae, and a carnivorous habit should thus be considered the main diagnostic character in systematic classification.


Assuntos
Carnivoridade , Poríferos/fisiologia , Animais , Evolução Biológica , DNA Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Filogenia , Poríferos/classificação , Poríferos/genética , Comportamento Predatório , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética
17.
Am J Clin Nutr ; 103(1): 218-30, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26657045

RESUMO

BACKGROUND: Vegetarians and others who do not eat meat have been observed to have lower incidence rates than meat eaters of some chronic diseases, but it is unclear whether this translates into lower mortality. OBJECTIVE: The purpose of this study was to describe mortality in vegetarians and comparable nonvegetarians in a large United Kingdom cohort. DESIGN: The study involved a pooled analysis of data from 2 prospective studies that included 60,310 persons living in the United Kingdom, comprising 18,431 regular meat eaters (who ate meat ≥5 times/wk on average), 13,039 low (less-frequent) meat eaters, 8516 fish eaters (who ate fish but not meat), and 20,324 vegetarians (including 2228 vegans who did not eat any animal foods). Mortality by diet group for each of 18 common causes of death was estimated with the use of Cox proportional hazards models. RESULTS: There were 5294 deaths before age 90 in >1 million y of follow-up. There was no significant difference in overall (all-cause) mortality between the diet groups: HRs in low meat eaters, fish eaters, and vegetarians compared with regular meat eaters were 0.93 (95% CI: 0.86, 1.00), 0.96 (95% CI: 0.86, 1.06), and 1.02 (95% CI: 0.94, 1.10), respectively; P-heterogeneity of risks = 0.082. There were significant differences in risk compared with regular meat eaters for deaths from circulatory disease [higher in fish eaters (HR: 1.22; 95% CI: 1.02, 1.46)]; malignant cancer [lower in fish eaters (HR: 0.82; 95% CI: 0.70, 0.97)], including pancreatic cancer [lower in low meat eaters and vegetarians (HR: 0.55; 95% CI: 0.36, 0.86 and HR: 0.48; 95% CI: 0.28, 0.82, respectively)] and cancers of the lymphatic/hematopoietic tissue [lower in vegetarians (HR: 0.50; 95% CI: 0.32, 0.79)]; respiratory disease [lower in low meat eaters (HR: 0.70; 95% CI: 0.53, 0.92)]; and all other causes [lower in low meat eaters (HR: 0.74; 95% CI: 0.56, 0.99)]. Further adjustment for body mass index left these associations largely unchanged. CONCLUSIONS: United Kingdom-based vegetarians and comparable nonvegetarians have similar all-cause mortality. Differences found for specific causes of death merit further investigation.


Assuntos
Doenças Cardiovasculares/mortalidade , Carnivoridade , Causas de Morte , Dieta , Neoplasias/mortalidade , Doenças Respiratórias/mortalidade , Vegetarianos , Adulto , Animais , Índice de Massa Corporal , Dieta Vegetariana , Ingestão de Alimentos , Comportamento Alimentar , Feminino , Humanos , Masculino , Carne , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Risco , Reino Unido/epidemiologia , Vegetarianos/estatística & dados numéricos
18.
J Immunol ; 195(1): 23-9, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26092814

RESUMO

Devil facial tumor disease (DFTD) is a transmissible cancer that has killed most of the Tasmanian devil (Sarcophilus harrissii) population. Since the first case appeared in the mid-1990s, it has spread relentlessly across the Tasmanian devil's geographic range. As Tasmanian devils only exist in Tasmania, Australia, DFTD has the potential to cause extinction of this species. The origin of DFTD was a Schwann cell from a female devil. The disease is transmitted when devils bite each other around the facial areas, a behavior synonymous with this species. Every devil that is 'infected' with DFTD dies from the cancer. Once the DFTD cells have been transmitted, they appear to develop into a cancer without inducing an immune response. The DFTD cancer cells avoid allogeneic recognition because they do not express MHC class I molecules on the cell surface. A reduced genetic diversity and the production of immunosuppressive cytokines may also contribute.


Assuntos
Mordeduras e Picadas/imunologia , Transmissão de Doença Infecciosa , Neoplasias Faciais/imunologia , Marsupiais/imunologia , Células de Schwann/imunologia , Animais , Mordeduras e Picadas/mortalidade , Mordeduras e Picadas/patologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Carnivoridade , Células Dendríticas/imunologia , Células Dendríticas/patologia , Neoplasias Faciais/mortalidade , Neoplasias Faciais/patologia , Feminino , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Masculino , Mortalidade , Células de Schwann/patologia , Tasmânia
19.
Rev. bras. enferm ; 68(2): 191-197, Mar-Apr/2015. tab
Artigo em Português | LILACS, BDENF - Enfermagem | ID: lil-752514

RESUMO

RESUMO Objetivo: analisar o desenvolvimento e a mobilização de competências relacionais, centrais no processo de cuidar, pelo estudante de enfermagem ao longo do seu processo de formação. Método: estudo descritivo-correlacional de abordagem quantitativa. A amostra foi constituída pelos estudantes do curso de enfermagem de uma Escola Superior de Saúde, no litoral de Portugal e os dados foram coletados através do Inventário de Competências Relacionais de Ajuda, já testado. Resultados: os estudantes adquirem gradualmente as competências genéricas, competências de comunicação e competências de contacto, atingindo a média mais alta no último ano do curso, enquanto na subescala competências empáticas os estudantes do 2º ano apresentam um valor médio superior. Conclusão: a idade e o ano do curso são variáveis decisivas na aquisição de competências específicas (empáticas e comunicação) pelos estudantes de enfermagem. .


RESUMEN Objetivo: este estudio analiza el desarrollo y la movilización de expertos relacional, central en la atención al estudiante de enfermería a lo largo de su processo formación. Método: se realizó un estudio descriptivo-correlacional de enfoque cuantitativo. La muestra incluyó a los alumnos del curso de enfermería de la Escuela de Salud, en la costa de Portugal y los datos fueron recogidos a través del Inventario de Habilidades Relational Ayuda, ya probado. Resultados: los resultados obtenidos indican que los estudantes adquirir gradualmente “habilidades blandas”, “habilidades de comunicación” y “habilidades de contacto”, alcanzando el promedio más alto en el último año, mientras que en subescala de “habilidades empáticas” estudiantes de segundo año tienen un valor promedio más alto. Conclusión: la edad y el año del curso son variables determinantes en la adquisición de habilidades específicas (Empática y la comunicación) de los estudiantes de enfermería. .


ABSTRACT Objective: to analyze the development and mobilization of relational skills central to the caring process among nursing students throughout their professional training. Method: this was a quantitative study, descriptive and cross-sectional in design. The sample consisted of nursing undergraduate students from the Higher School of Health Sciences, in the city of Évora, Portugal. Data were collected using the previously validated Helping Relational Skills Inventory. Results: the students gradually acquired “generic skills”, “communication skills” and “contact skills”, presenting the highest mean score in the last year of the program. However, the highest mean score for the “empathetic skills” subscale was presented by second-year students. Conclusion: age and year in program were found to be decisive variables regarding the acquisition of specifi c skills (empathetic and communication) by nursing students. .


Assuntos
Humanos , Animais , Agricultura/métodos , Artrópodes/classificação , Cadeia Alimentar , Pradaria , Modelos Estatísticos , Artrópodes/fisiologia , Biodiversidade , Biomassa , Carnivoridade/fisiologia , Alemanha , Herbivoria/fisiologia , Poaceae/fisiologia
20.
PLoS One ; 10(3): e0119303, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25760348

RESUMO

The eastern quoll (Dasyurus viverrinus) is a medium-sized Australian marsupial carnivore that has recently undergone a rapid and severe population decline over the 10 years to 2009, with no sign of recovery. This decline has been linked to a period of unfavourable weather, but subsequent improved weather conditions have not been matched by quoll recovery. A recent study suggested another mechanism: that declines in Tasmanian devil (Sarcophilus harrisii) populations, due to the spread of the fatal Devil Facial Tumour Disease, have released feral cats (Felis catus) from competitive suppression, with eastern quoll declines linked to a subsequent increase in cat sightings. Yet current evidence of intraguild suppression among devils, cats and quolls is scant and equivocal. We therefore assessed the influences of top-down effects on abundance and activity patterns among devils, feral cats and eastern quolls. Between 2011 and 2013, we monitored four carnivore populations using longitudinal trapping and camera surveys, and performed camera surveys at 12 additional sites throughout the eastern quoll's range. We did not find evidence of a negative relationship between devil and cat abundance, nor of higher cat abundance in areas where devil populations had declined the longest. Cats did not appear to avoid devils spatially; however, there was evidence of temporal separation of cat and devil activity, with reduced separation and increasing nocturnal activity observed in areas where devils had declined the longest. Cats and quolls used the same areas, and there was no evidence that cat and quoll abundances were negatively related. Temporal overlap in observed cat and quoll activity was higher in summer than in winter, but this seasonal difference was unrelated to devil declines. We suggest that cats did not cause the recent quoll decline, but that predation of juvenile quolls by cats could be inhibiting low density quoll populations from recovering their former abundance through a 'predator pit' effect following weather-induced decline. Predation intensity could increase further should cats become increasingly nocturnal in response to devil declines.


Assuntos
Marsupiais , Animais , Carnivoridade , Gatos , Marsupiais/fisiologia , Dinâmica Populacional , Tasmânia
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