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1.
Ecol Evol ; 11(18): 12630-12638, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34594526

RESUMO

Natal dispersal is a key demographic process for evaluating the population rate of change, especially for long-lived, highly mobile species. This process is largely unknown for reintroduced populations of endangered avian species. We evaluated natal dispersal distances (NDD) for male and female Whooping Cranes (Grus americana) introduced into two locations in central Wisconsin (Necedah National Wildlife Refuge, or NNWR, and the Eastern Rectangle, or ER) using a series of demographic, spatial, and life history-related covariates. Data were analyzed using gamma regression models with a log-link function and compared using Akaike information criterion corrected for small sample sizes (AICc). Whooping Cranes released in the ER dispersed 261% further than those released into NNWR, dispersal distance increased 4% for each additional nesting pair, decreased about 24% for males as compared to females, increased by 21% for inexperienced pairs, and decreased by 3% for each additional year of age. Natal philopatry, habitat availability or suitability, and competition for breeding territories may be influencing observed patterns of NDD. Whooping Cranes released in the ER may exhibit longer NDD due to fragmented habitat or conspecific attraction to established breeding pairs at NNWR. Additionally, sex-biased dispersal may be increasing in this population as there are more individuals from different natal sites forming breeding pairs. As the population grows and continues to disperse, the drivers of NDD patterns may change based on individual or population behavior.

2.
Clin Cancer Res ; 18(21): 5888-901, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23072969

RESUMO

PURPOSE: During glutaminolysis, glutamine is catabolized to glutamate and incorporated into citric acid cycle and lipogenesis. Serum glutamate levels were measured in patients with primary prostate cancer or metastatic castrate-resistant prostate cancer (mCRPCa) to establish clinical relevance. The effect of glutamate deprivation or blockade by metabotropic glutamate receptor 1 (GRM1) antagonists was investigated on prostate cancer cells' growth, migration, and invasion to establish biologic relevance. EXPERIMENTAL DESIGN: Serum glutamate levels were measured in normal men (n = 60) and patients with primary prostate cancer (n = 197) or mCRPCa (n = 109). GRM1 expression in prostatic tissues was examined using immunohistochemistry (IHC). Cell growth, migration, and invasion were determined using cell cytotoxicity and modified Boyden chamber assays, respectively. Apoptosis was detected using immunoblotting against cleaved caspases, PARP, and γ-H2AX. RESULTS: Univariate and multivariate analyses showed significantly higher serum glutamate levels in Gleason score ≥ 8 than in the Gleason score ≤ 7 and in African Americans than in the Caucasian Americans. African Americans with mCRPCa had significantly higher serum glutamate levels than those with primary prostate cancer or benign prostate. However, in Caucasian Americans, serum glutamate levels were similar in normal research subjects and patients with mCRPC. IHC showed weak or no expression of GRM1 in luminal acinar epithelial cells of normal or hyperplastic glands but high expression in primary or metastatic prostate cancer tissues. Glutamate deprivation or blockade decreased prostate cancer cells' proliferation, migration, and invasion and led to apoptotic cell death. CONCLUSIONS: Glutamate expression is mechanistically associated with and may provide a biomarker of prostate cancer aggressiveness.


Assuntos
Ácido Glutâmico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Adulto , Negro ou Afro-Americano , Apoptose/efeitos dos fármacos , Estudos de Casos e Controles , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Receptores de Glutamato Metabotrópico/metabolismo , Riluzol/farmacologia , População Branca
3.
J Ocul Pharmacol Ther ; 27(2): 115-21, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21413860

RESUMO

PURPOSE: Hypoxia of the retina and optic nerve head (ONH) is believed to be pivotal in the development of ocular vascular disorders, including diabetic macular edema (DME). Glucocorticoids are among the most effective agents for the treatment of back of the eye diseases. However, this class of compounds is highly liable to increase intraocular pressure (IOP) and does not improve ocular perfusion or tissue oxygenation. Nitric oxide (NO) has vasodilating properties and lowers IOP in experimental models and humans, suggesting that its properties might complement those of glucocorticoids. NCX 434 is an NO-donating triamcinolone acetonide (TA) that is less likely to increase IOP while targeting both the vascular and inflammatory components of DME. METHODS: NCX 434 was studied in vitro with respect to its NO-releasing properties in isolated methoxamine-precontracted rabbit aortic rings and glucocorticoid-like activity in recombinant human glucocorticoid receptors. IOP and oxygen saturation in the ONH and overlaying arteries and veins were studied in the anesthetized cynomolgus monkey. Measurements were taken using, respectively, an applanation tonometer and a hyperspectral imaging system before and 7, 14, 21, 31 and 41 days after the intravitreal injection of NCX 434 (5.8 mg/eye) or TA equimolar doses (4.0 mg/eye). RESULTS: NCX 434 inhibited (3)H-dexamethasone-specific binding (IC(50)=34±5 nM) on human glucocorticoid receptors and elicited NO-dependent aortic ring relaxation (EC(50) of 0.5±0.1 µM, E(max) 98.9%). In monkey eyes, NCX 434 enhanced, whereas TA did not, oxygen saturation in various ONH areas (*P<0.05 vs. basal), decreased it in veins, and did not affect it in the overlaying arteries. Neither NCX 434 nor TA altered IOP significantly at all time points. However, at 31 days post-treatment TA appeared to start increasing IOP (Δ(IOP)=+3.31±0.51 mmHg, 30.8%, over baseline, NS). CONCLUSIONS: NCX 434 enhances ocular tissue oxygenation. This feature appears to depend on its NO-donating properties; thus, the compound deserves to be further investigated for the treatment of DME and other ocular disorders with impaired ocular perfusion.


Assuntos
Retinopatia Diabética/tratamento farmacológico , Edema Macular/tratamento farmacológico , Nitratos/administração & dosagem , Doadores de Óxido Nítrico/administração & dosagem , Disco Óptico/efeitos dos fármacos , Oxigênio/metabolismo , Triancinolona Acetonida/análogos & derivados , Triancinolona Acetonida/administração & dosagem , Animais , Aorta/efeitos dos fármacos , Aorta/fisiologia , Dexametasona/metabolismo , Pressão Intraocular/efeitos dos fármacos , Injeções Intravítreas , Macaca fascicularis , Masculino , Disco Óptico/metabolismo , Coelhos
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