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1.
Ecology ; 103(5): e3630, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35048367

RESUMO

Kelp forests are among the most productive ecosystems on Earth. In combination with their close proximity to the shore, the productivity and biodiversity of these ecosystems generate a wide range of ecosystem services including supporting (e.g., primary production, habitat), regulating (e.g., water flow, coastal erosion), provisioning (e.g., commercial and recreational fisheries), and cultural (e.g., recreational, artisanal) services. For these reasons, kelp forests have long been the target of ecological studies. However, with few exceptions, these studies have been localized and short term (<5 years). In 1999, recognizing the importance of large-scale, long-term studies for understanding the structure, functioning, and dynamics of coastal marine ecosystems, and for informing policy, the Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO) designed and initiated a large-scale, long-term monitoring study of kelp forest ecosystems along 1400 km of coast stretching from southern California to southern Oregon, USA. The purpose of the study has been to characterize the spatial and temporal patterns of kelp forest ecosystem structure and evaluate the relative contributions of biological and environmental variables derived from external sources (e.g., sea otter density, Chl-a concentration, sea surface temperature, wave energy) in explaining observed spatial and temporal patterns. For this purpose, the ecological community (i.e., density, percent cover, or biomass of conspicuous fishes, invertebrates, and macroalgae) and geomorphological attributes (bottom depth, substratum type, and vertical relief) of kelp forest ecosystems have been surveyed annually using SCUBA divers trained in both scientific diving and data collection techniques and the identification of kelp forest species. The study region spans distinct ecological and biogeographic provinces, which enables investigations of how variation in environmental drivers and distinctive species compositions influence community structure, and its response to climate-related environmental change across a portion of the California Current Large Marine Ecosystem. These data have been used to inform fisheries management, design and evaluate California's state-wide network of marine protected areas (MPAs), and assess the ecological consequences of climate change (e.g., marine heatwaves). Over time, the spatial and temporal design of the monitoring program was adapted to fill its role in evaluating the ecological responses to the establishment of MPAs. There are no copyright restrictions; please cite this paper when data are used.


Assuntos
Kelp , Animais , Biodiversidade , California , Ecossistema , Florestas , Oregon
2.
Mol Ecol ; 28(7): 1611-1623, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30739378

RESUMO

Marine species with pelagic larvae typically exhibit little population structure, suggesting long-distance dispersal and high gene flow. Directly quantifying dispersal of marine fishes is challenging but important, particularly for the design of marine protected areas (MPAs). Here, we studied kelp rockfish (Sebastes atrovirens) sampled along ~25 km of coastline in a boundary current-dominated ecosystem and used genetic parentage analysis to identify dispersal events and characterize them, because the distance between sedentary parents and their settled offspring is the lifetime dispersal distance. Large sample sizes and intensive sampling are critical for increasing the likelihood of detecting parent-offspring matches in such systems and we sampled more than 6,000 kelp rockfish and analysed them with a powerful set of 96 microhaplotype markers. We identified eight parent-offspring pairs with high confidence, including two juvenile fish that were born inside MPAs and dispersed to areas outside MPAs, and four fish born in MPAs that dispersed to nearby MPAs. Additionally, we identified 25 full-sibling pairs, which occurred throughout the sampling area and included all possible combinations of inferred dispersal trajectories. Intriguingly, these included two pairs of young-of-the-year siblings with one member each sampled in consecutive years. These sibling pairs suggest monogamy, either intentional or accidental, which has not been previously demonstrated in rockfishes. This study provides the first direct observation of larval dispersal events in a current-dominated ecosystem and direct evidence that larvae produced within MPAs are exported both to neighbouring MPAs and to proximate areas where harvest is allowed.


Assuntos
Distribuição Animal , Genética Populacional , Perciformes/genética , Animais , California , Ecossistema , Pesqueiros , Marcadores Genéticos , Haplótipos , Repetições de Microssatélites , Linhagem
3.
Arch Pathol Lab Med ; 137(6): 820-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23030695

RESUMO

CONTEXT: The therascreen KRAS RGQ polymerase chain reaction kit is being developed as a companion diagnostic to aid clinicians, through detection of KRAS mutations, in the identification of patients with metastatic colorectal cancer (mCRC) who are more likely to benefit from cetuximab. OBJECTIVES: To assess whether KRAS mutation status, determined by using the therascreen KRAS kit, is a predictive marker of cetuximab efficacy. DESIGN: Tissue samples were obtained from patients with mCRC treated on the National Cancer Institute of Canada Clinical Trials Group (NCIC CTG) CO.17 phase 3 study of cetuximab plus best supportive care (BSC) versus BSC alone. Tumor DNA samples were assessed for the presence of KRAS mutations by using the therascreen KRAS kit. Efficacy and safety were assessed to determine whether mutation status was predictive of outcomes. Results.-Evaluable samples were available from 453 patients (79.2%) enrolled in the NCIC CTG CO.17 trial. The KRAS wild-type subset represented 54.1% (245 of 453) of the evaluated population. Median overall survival of patients with KRAS wild-type tumors was 8.6 months among those who received cetuximab plus BSC and 5.0 months among patients who received BSC alone (hazard ratio [HR], 0.63; P = .002). Among patients with KRAS mutant mCRC, no meaningful difference in overall survival was observed between arms (HR, 0.91; P = .55). These results are consistent with a previous report that analyzed patient tumor samples by using bidirectional sequencing. CONCLUSIONS: These data support the utility of the therascreen KRAS kit as a means of selecting patients who may benefit from cetuximab therapy.


Assuntos
Adenocarcinoma/secundário , Códon sem Sentido , Códon/genética , Neoplasias Colorretais/patologia , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/uso terapêutico , Cetuximab , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Proto-Oncogênicas p21(ras) , Taxa de Sobrevida
4.
Ecology ; 92(11): 2108-16, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22164835

RESUMO

We took advantage of regional differences in environmental forcing and consumer abundance to examine the relative importance of nutrient availability (bottom-up), grazing pressure (top-down), and storm waves (disturbance) in determining the standing biomass and net primary production (NPP) of the giant kelp Macrocystis pyrifera in central and southern California. Using a nine-year data set collected from 17 sites we show that, despite high densities of sea urchin grazers and prolonged periods of low nutrient availability in southern California, NPP by giant kelp was twice that of central California where nutrient concentrations were consistently high and sea urchins were nearly absent due to predation by sea otters. Waves associated with winter storms were consistently higher in central California, and the loss of kelp biomass to winter wave disturbance was on average twice that of southern California. These observations suggest that the more intense wave disturbance in central California limited NPP by giant kelp under otherwise favorable conditions. Regional patterns of interannual variation in NPP were similar to those of wave disturbance in that year-to-year variation in disturbance and NPP were both greater in southern California. Our findings provide strong evidence that regional differences in wave disturbance overwhelmed those of nutrient supply and grazing intensity to determine NPP by giant kelp. The important role of disturbance in controlling NPP revealed by our study is likely not unique to giant kelp forests, as vegetation dynamics in many systems are dominated by post-disturbance succession with climax communities being relatively uncommon. The effects of disturbance frequency may be easier to detect in giant kelp because it is fast growing and relatively short lived, with cycles of disturbance and recovery occurring on time scales of years. Much longer data sets (decades to centuries) will likely be needed to properly evaluate the role of disturbance relative to other processes in determining patterns of NPP in other systems.


Assuntos
Ecossistema , Kelp/fisiologia , Movimentos da Água , Animais , California , Lontras , Ouriços-do-Mar , Estações do Ano , Succinimidas , Fatores de Tempo
5.
J Cell Biochem ; 98(5): 1203-20, 2006 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16514668

RESUMO

The biological activities of parathyroid hormone (PTH) on bone are quite complex as demonstrated by its catabolic and anabolic activities on the skeleton. Although there have been many reports describing genes that are regulated by PTH in osteoblast cells, the goal of this study was to utilize a well-established in vivo PTH anabolic treatment regimen to identify genes that mediate bone anabolic effects of PTH. We identified a gene we named PTH anabolic induced gene in bone (PAIGB) that has been reported as brain and acute leukemia cytoplasmic (BAALC). Therefore, using the latter nomenclature, we have discovered that BAALC is a PTH-regulated gene whose mRNA expression was selectively induced in rat tibiae nearly 100-fold (maximal) by a PTH 1-34 anabolic treatment regimen in a time-dependent manner. Although BAALC is broadly expressed, PTH did not regulate BAALC expression in other PTH receptor expressing tissues and we find that the regulation of BAALC protein by PTH in vivo is confined to mature osteoblasts. Further in vitro studies using rat UMR-106 osteoblastic cells show that PTH 1-34 rapidly induces BAALC mRNA expression maximally by 4 h while the protein was induced by 8 h. In addition to being regulated by PTH 1-34, BAALC expression can also be induced by other bone forming factors including PGE(2) and 1,25 dihydroxy vitamin D(3). We determined that BAALC is regulated by PTH predominantly through the cAMP/PKA pathway. Finally, we demonstrate in MC3T3-E1 osteoblastic cells that BAALC overexpression regulates markers of osteoblast differentiation, including downregulating alkaline phosphatase and osteocalcin expression while inducing osteopontin expression. We also demonstrate that these transcriptional responses mediated by BAALC are similar to the responses elicited by PTH 1-34. These data, showing BAALC overexpression can mimic the effect of PTH on markers of osteoblast differentiation, along with the observations that BAALC is induced selectively with a bone anabolic treatment regimen of PTH (not a catabolic treatment regimen), suggest that BAALC may be an important mediator of the PTH anabolic action on bone cell function.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Hormônio Paratireóideo/farmacologia , Sequência de Aminoácidos , Animais , Biomarcadores , Calcitriol/farmacologia , Diferenciação Celular , Células Cultivadas , Sequência Conservada , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Dinoprostona/farmacologia , Feminino , Humanos , Dados de Sequência Molecular , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Ratos , Ratos Sprague-Dawley , Alinhamento de Sequência , Transdução de Sinais
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