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1.
Ecology ; 100(11): e02863, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31398280

RESUMO

In 2014, a DNA-based phylogenetic study confirming the paraphyly of the grass subtribe Sporobolinae proposed the creation of a large monophyletic genus Sporobolus, including (among others) species previously included in the genera Spartina, Calamovilfa, and Sporobolus. Spartina species have contributed substantially (and continue contributing) to our knowledge in multiple disciplines, including ecology, evolutionary biology, molecular biology, biogeography, experimental ecology, biological invasions, environmental management, restoration ecology, history, economics, and sociology. There is no rationale so compelling to subsume the name Spartina as a subgenus that could rival the striking, global iconic history and use of the name Spartina for over 200 yr. We do not agree with the subjective arguments underlying the proposal to change Spartina to Sporobolus. We understand the importance of both the objective phylogenetic insights and of the subjective formalized nomenclature and hope that by opening this debate we will encourage positive feedback that will strengthen taxonomic decisions with an interdisciplinary perspective. We consider that the strongly distinct, monophyletic clade Spartina should simply and efficiently be treated as the genus Spartina.


Assuntos
Poaceae , Filogenia
2.
Am J Bot ; 101(3): 448-58, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24607513

RESUMO

PREMISE OF THE STUDY: Phenotypic acclimation of individual plants and genetic differentiation by natural selection within invasive populations are two potential mechanisms that may confer fitness advantages and allow plants to cope with environmental variation. The invasion of Spartina densiflora across a wide latitudinal gradient from California (USA) to British Columbia (Canada) provides a natural model system to study the potential mechanisms underlying the response of invasive populations to substantial variation in climate and other environmental variables. METHODS: We examined morphological and physiological leaf traits of Spartina densiflora plants in populations from invaded estuarine sites across broad latitudinal and climate gradients along the Pacific west coast of North America and in favorable conditions in a common garden experiment. KEY RESULTS: Our results show that key foliar traits varied widely among populations. Most foliar traits measured in the field were lower than would be expected under ideal growing conditions. Photosynthetic pigment concentrations at higher latitudes were lower than those observed at lower latitudes. Greater leaf rolling, reduced leaf lengths, and lower chlorophyll and higher carbon concentrations were observed with anoxic sediments. Lower chlorophyll to carotenoids ratios and reduced nitrogen concentrations were correlated with sediment salinity. Our results suggest that the variations of foliar traits recorded in the field are a plastic phenotypic response that was not sustained under common garden conditions. CONCLUSIONS: SPARTINA DENSIFLORA shows wide differences in its foliar traits in response to environmental heterogeneity in salt marshes, which appears to be the result of phenotypic plasticity rather than genetic differentiation.


Assuntos
Aclimatação , Oxigênio/metabolismo , Poaceae/fisiologia , Carbono/metabolismo , Clorofila/metabolismo , Mudança Climática , Meio Ambiente , Sedimentos Geológicos , Espécies Introduzidas , América do Norte , Oxirredução , Fenótipo , Folhas de Planta/fisiologia , Salinidade , Áreas Alagadas
3.
Orthopedics ; 36(9): e1213-6, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24025016

RESUMO

Osteochondritis dissecans is a disorder of unknown etiology that can result in fragmentation of osteochondral surfaces, most commonly of the knee, shoulder, elbow, and ankle. This may lead to sequelae of pain and an inability to participate in desired activities. Multiple theories exist as to the true cause of the disorder, but none have been fully proven. One such proposed etiology is genetic causation. Familial cases of osteochondritis dissecans are rare, yet these cases offer support to growing evidence that may support a genetic link. This article describes osteochondritis dissecans lesions of the femoral trochlea in monozygotic (identical) twins. Both twins presented with similar symptoms 1 year apart. Neither twin had any clear inciting trauma. Magnetic resonance imaging revealed osteochondral lesions in similar positions of the lateral trochlear of the same knee in both brothers. Osteochondral autograft transfer and tibial tubercle anteromedialization were performed on both patients. An identical postoperative protocol was followed, and recovery with full return to sport was comparable for the brothers. To the authors' knowledge, only 1 other case report exists of osteochondritis dissecans lesions in monozygotic twins. Although debate continues regarding the true etiology of this disorder, cases of identical twins presenting with a similar disease process are highly suggestive of a genetic component and may lead to early identification and treatment of these lesions. Continued research in the area of osteochondritis dissecans and its genetic basis is needed to completely understand this disorder.


Assuntos
Transplante Ósseo/métodos , Doenças em Gêmeos , Fêmur/transplante , Articulação do Joelho , Osteocondrite Dissecante/diagnóstico , Gêmeos Monozigóticos , Adolescente , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Osteocondrite Dissecante/cirurgia , Transplante Autólogo
4.
Arthroscopy ; 26(9): 1162-71, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20615650

RESUMO

PURPOSE: The purpose of this outcome analysis was to evaluate the clinical presentation of isolated posterior labral tears resulting from athletic injury and to use multiple outcome measurements to evaluate postoperative results after arthroscopic repair with respect to satisfaction, function, and return to sport. METHODS: Seventy-five consecutive patients injured during athletic activity were treated surgically during the 2-year period from 2005 to 2006 for labral pathologies. Twenty-eight patients were treated for isolated posterior labral tears. Of these, all underwent arthroscopic repair of their tears. The mechanism of injury was trauma to a previously asymptomatic shoulder during sports. The patients' mean age was 21 years, and they were evaluated with American Shoulder and Elbow Surgeons; University of California, Los Angeles; Rowe; and visual analog scale scores, as well as active motion and dynamometric strength testing. Scores and measurements were obtained preoperatively and postoperatively at 3, 6, and 12 months and yearly thereafter. RESULTS: In our athletic population undergoing surgical management for labral pathology, 37% of patients (28 of 75) were found to have purely posterior labral lesions after an athletic injury. On intraoperative examination, an element of posterior laxity was seen in only 29% of patients with these tears. At 24 months, significant improvements were observed in the American Shoulder and Elbow Surgeons; University of California, Los Angeles; Rowe; and visual analog scale scores. Increases in forward flexion and external rotation strength were also noted. Return to sport was achieved in 26 of 28 patients (93%). A 93% patient satisfaction rate was observed for arthroscopic posterior labral repairs at more than 24 months. CONCLUSIONS: Our patient-athletes presented with painful, dysfunctional shoulders that inhibited performance in their chosen sport. Arthroscopic evaluation and repair of these posterior labral lesions resulted in 26 of 28 patients (93%) returning to sport and 23 of 28 (82%) returning without any limitations. LEVEL OF EVIDENCE: Level IV, therapeutic case series.


Assuntos
Artroscopia/métodos , Traumatismos em Atletas/cirurgia , Ligamentos Articulares/lesões , Ligamentos Articulares/cirurgia , Lesões do Ombro , Articulação do Ombro/cirurgia , Adolescente , Adulto , Traumatismos em Atletas/diagnóstico , Traumatismos em Atletas/reabilitação , Feminino , Seguimentos , Humanos , Masculino , Satisfação do Paciente , Recuperação de Função Fisiológica , Luxação do Ombro/complicações , Resultado do Tratamento , Adulto Jovem
5.
Biofouling ; 25(7): 645-55, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20183123

RESUMO

Fouling of ships is an important historical and enduring transfer mechanism of marine nonindigenous species (NIS). Although containerships have risen to the forefront of global maritime shipping since the 1950s, few studies have directly sampled fouling communities on their submerged surfaces, and little is known about differences in the fouling characteristics among commercial ship types. Twenty-two in-service containerships at the Port of Oakland (San Francisco Bay, California) were sampled to test the hypothesis that the extent and taxonomic richness of fouling would be low on this type of ship, resulting from relatively fast speeds and short port durations. The data showed that the extent of macroorganisms (invertebrates and algae) was indeed low, especially across the large surface areas of the hull. Less than 1% of the exposed hull was colonized for all apart from one vessel. These ships had submerged surface areas of >7000 m(2), and fouling coverage on this area was estimated to be <17 m(2) per vessel, with zero biota detected on the hulls of many vessels. The outlying smaller vessel (4465 m(2)) had an estimated coverage of 90% on the hull and also differed substantially from the other ships in terms of its recent voyage history, shorter voyage range and slower speeds. Despite the low extent of fouling, taxonomic richness was high among vessels. Consistent with recent studies, a wide range of organisms were concentrated at more protected and heterogeneous (non-hull) niche areas, including rudders, stern tubes and intake gratings. Green algae and barnacles were most frequently sampled among vessels, but hydroids, bryozoans, bivalves and ascidians were also recorded. One vessel had 20 different species in its fouling assemblage, including non-native species (already established in San Francisco Bay) and mobile species that were not detected in visual surveys. In contrast to other studies, dry dock block areas did not support many organisms, despite little antifouling deterrence in some cases. Comparisons with previous studies suggest that the accumulation of fouling on containerships may be lower than on other ship types (eg bulkers and general cargo vessels), but more data are needed to determine the hierarchy of factors contributing to differences in the extent of macrofouling and non-native species vector risks within the commercial fleet.


Assuntos
Incrustação Biológica , Invertebrados/crescimento & desenvolvimento , Invertebrados/fisiologia , Navios , Animais , Biodiversidade , California , Comércio , Invertebrados/classificação , Biologia Marinha , Dinâmica Populacional , Especificidade da Espécie
6.
Mar Pollut Bull ; 58(3): 366-74, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19108853

RESUMO

Ballast water is a dominant mechanism for the interoceanic and transoceanic dispersal of aquatic non-native species (ANS), but few studies have addressed ANS transfers via smaller scale vessel movements. We analyzed ballast water reporting records and ANS occurrence data from four US West Coast port systems to examine patterns of intra-coastal ballast water transfer, and assess how ballast transfers may have influenced the secondary spread of ANS. In 2005, one third of the vessels arriving to the US West Coast originated at one of four West Coast port systems (intra-coastal traffic). These vessels transported and discharged 27% (5,987,588 MT) of the total ballast water volume discharged at these ports that year. The overlap of ANS (shared species) among port systems varied between 3% and 80%, with the largest overlap occurring between San Francisco Bay and LA/Long Beach. Our results suggest that intra-coastal ballast water needs further consideration as an invasion pathway, especially as efforts to promote short-sea shipping are being developed.


Assuntos
Conservação dos Recursos Naturais , Navios , Ecossistema , Monitoramento Ambiental , Oceano Pacífico , Medição de Risco , Estados Unidos
7.
Mar Pollut Bull ; 56(9): 1538-44, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18639904

RESUMO

Vector management is the primary method for reducing and preventing nonindigenous species (NIS) invasions and their ecological and economic consequences. This study was the first to examine the efficacy of in-water scrubbing using a submersible cleaning and maintenance platform (SCAMP) to prevent invertebrate species transfers from a heavily fouled obsolete vessel. Initially, prior to treatment, 37 species were recorded in a biofouling matrix that reached 30cm depth in some locations. The bryozoan Conopeum chesapeakensis, and bivalves Mytilopsis leucophaeata and Ischadium recurvum, were dominant sessile species that created structure, supporting mobile biota that included crabs and the associated parasitic barnacle Loxothylacus panopae. Scrubbing had the effect of significantly reducing organism extent and the number of species per sample, but a substantial and diverse (30 species) residual fouling community remained across the entire vessel. Further assessments of management options are needed to prevent potentially damaging NIS transfers. Additional measures taken within an integrated vector management (IVM) strategy may further improve invasion prevention measures.


Assuntos
Biofilmes/crescimento & desenvolvimento , Ecossistema , Recuperação e Remediação Ambiental/métodos , Navios , Recuperação e Remediação Ambiental/instrumentação , Especificidade da Espécie
8.
J Orthop Res ; 20(3): 483-9, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12038621

RESUMO

A frequent long-term complication of total joint arthroplasty is aseptic loosening, the end result of wear debris production, synovial macrophage activation, inflammatory mediator release, and osteolysis about the implant-bone or cement-bone interface. To elucidate the mechanisms of particle-induced macrophage activation and mediator production, we studied early signal transduction events using J774A.1 macrophages and 3 microm titanium particles. Treating macrophages with herbimycin A or genistein, two inhibitors of protein tyrosine kinases (PTKs), inhibited titanium phagocytosis as well as secretion of tumor necrosis factor-alpha (TNF-alpha) and prostaglandin-E2 (PGE2) in a dose-dependent manner. Both processes therefore depend on a PTK signaling cascade. Specifically, macrophage exposure to titanium-induced phosphorylation of multiple proteins including the Src kinase Lyn and phospholipase Cgamma-1 and Cgamma-2. Phosphorylation peaked within 2 min and returned to baseline within 45 min. Similar but not identical phosphorylation patterns were obtained when cells were stimulated with titanium preincubated with serum or albumin, suggesting distinct signal transduction pathways dependent on particle coating.


Assuntos
Isoenzimas/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Titânio/farmacologia , Fosfolipases Tipo C/metabolismo , Quinases da Família src/metabolismo , Linhagem Celular , Ativação Enzimática/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Fagocitose/fisiologia , Fosfolipase C gama , Fosforilação/efeitos dos fármacos
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