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1.
PLoS One ; 14(1): e0210865, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30703124

RESUMO

Forest management guidelines for rare or declining species in the Pacific Northwest, USA, include both late successional reserves and specific vegetation management criteria. However, whether current management practices for well-studied species such as northern spotted owls (Strix occidentallis caurina) can aid in conserving a lesser known subspecies-Humboldt martens (Martes caurina humboldtensis)-is unclear. To address the lack of information for martens in coastal Oregon, USA, we quantified vegetation characteristics at locations used by Humboldt martens and spotted owls in two regions (central and southern coast) and at two spatial scales (the site level summarizing extensive vegetation surveys and regionally using remotely sensed vegetation and estimated habitat models). We estimated amount of predicted habitat for both species in established reserves. If predicted overlap in established reserves was low, then we reported vegetation characteristics to inform potential locations for reserves or management opportunities. In the Central Coast, very little overlap existed in vegetation characteristics between Humboldt martens and spotted owls at either the site or regional level. Humboldt martens occurred in young forests composed of small diameter trees with few snags or downed logs. Humboldt martens were also found in areas with very dense vegetation when overstory canopy and shrub cover percentages were combined. In the South Coast, Humboldt martens occurred in forests with smaller diameter trees than spotted owl sites on average. Coastal Humboldt martens may use stands of predicted high quality spotted owl habitat in the Pacific Northwest. Nonetheless, our observations suggest that coastal Humboldt martens exist in areas that include a much higher diversity of conifer size classes as long as extensive dense shrub cover, predominantly in the form of high salal and evergreen huckleberry, are available. We suggest that managers consider how structural characteristics (e.g., downed logs, shrub cover, patch size), are associated with long-term species persistence rather than relying on reserves based on broad cover types. Describing vegetation may partially describe suitability, but available prey or predation risk ultimately influence likelihood of individual Humboldt marten use. Guidelines for diversifying vegetation management, and retaining or restoring appropriate habitat conditions at both the stand level and regionally, may increase management flexibility and identify forest conditions that support both spotted owls and Humboldt martens.


Assuntos
Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Florestas , Mustelidae/fisiologia , Estrigiformes/fisiologia , Animais , Oregon , Plantas
2.
J Exp Biol ; 219(Pt 11): 1760-71, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-26994176

RESUMO

Locomotion is necessary for survival in most animal species. However, injuries to the appendages mediating locomotion are common. We assess the recovery of walking in Drosophila melanogaster following leg amputation. Whereas flies pre-amputation explore open arenas in a symmetric fashion on average, foreleg amputation induces a strong turning bias away from the side of the amputation. However, we find that unbiased walking behavior returns over time in wild-type flies, while recovery is significantly impaired in proprioceptive mutants. To identify the biomechanical basis of this locomotor impairment and recovery, we then examine individual leg motion (gait) at a fine scale. A minimal mathematical model that links neurodynamics to body mechanics during walking shows that redistributing leg forces between the right and left side enables the observed recovery. Altogether, our study suggests that proprioceptive input from the intact limbs plays a crucial role in the behavioral plasticity associated with locomotor recovery after injury.


Assuntos
Drosophila melanogaster/fisiologia , Locomoção/fisiologia , Propriocepção/fisiologia , Amputação Cirúrgica , Animais , Fenômenos Biomecânicos , Calibragem , Extremidades/fisiologia , Marcha/fisiologia , Cadeias de Markov , Modelos Biológicos
3.
Chronic Obstr Pulm Dis ; 2(1): 8-16, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25914898

RESUMO

BACKGROUND: Cardiovascular diseases are frequent and a major cause of death in patients with chronic obstructive pulmonary disease (COPD). In the general population, various fat depots including abdominal visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and liver fat have been linked to increased risk of cardiovascular diseases. We hypothesize that these adipose tissue compartments are associated with myocardial infarction (MI) in patients with COPD. METHODS: We collected measures of VAT and SAT areas and liver attenuation on the computed tomography scan of the chest from 1267 patients with COPD. MI was a self-reported physician-diagnosed outcome. The association between fat depots and self-reported history of MI was assessed by logistic regression analysis in which the patients within the 2 lowest tertiles of VAT and SAT areas were the reference group. RESULTS: Eighty three patients (6.6%) reported a history of MI at the time of enrollment. Compared to patients who did not have an MI episode, those who had a prior MI had a higher VAT area (mean ± SD, 303.4 ± 208.5 vs. 226.8 ± 172.6 cm2; P=0.002) with no differences in SAT area and liver fat. After adjustment for age, gender, obesity, pack years of smoking, hypertension, high cholesterol, and diabetes, patients within the upper tertile (vs. those in the lower tertiles) of VAT area had increased odds of MI (odds ratio [OR] 1.86, 95% confidence interval [CI] 1.02 - 3.41). CONCLUSION: Increased abdominal visceral fat is independently associated with a history of MI in individuals with COPD.

4.
BMC Cancer ; 13: 140, 2013 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-23517112

RESUMO

BACKGROUND: Malignant pleural mesothelioma (MPM) is an aggressive malignancy closely associated with asbestos exposure and extremely resistant to current treatments. It exhibits a steady increase in incidence, thus necessitating an urgent development of effective new treatments. METHODS: Proteasome inhibitors (PIs) and TNFα-Related Apoptosis Inducing Ligand (TRAIL), have emerged as promising new anti-MPM agents. To develop effective new treatments, the proapoptotic effects of PIs, MG132 or Bortezomib, and TRAIL were investigated in MPM cell lines NCI-H2052, NCI-H2452 and NCI-H28, which represent three major histological types of human MPM. RESULTS: Treatment with 0.5-1 µM MG132 alone or 30 ng/mL Bortezomib alone induced a limited apoptosis in MPM cells associated with the elevated Mcl-1 protein level and hyperactive PI3K/Akt signaling. However, whereas 10-20 ng/ml TRAIL alone induced a limited apoptosis as well, TRAIL and PI combination triggered a robust apoptosis in all three MPM cell lines. The robust proapoptotic activity was found to be the consequence of a positive feedback mechanism-governed amplification of caspase activation and cleavage of both Mcl-1 and Akt proteins, and exhibited a relative selectivity in MPM cells than in non-tumorigenic Met-5A mesothelial cells. CONCLUSION: The combinatorial treatment using TRAIL and PI may represent an effective new treatment for MPMs.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Pulmonares/patologia , Mesotelioma/patologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Neoplasias Pleurais/patologia , Inibidores de Proteassoma/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Western Blotting , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Terapia Combinada , Citometria de Fluxo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mesotelioma/tratamento farmacológico , Mesotelioma/genética , Mesotelioma Maligno , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Neoplasias Pleurais/tratamento farmacológico , Neoplasias Pleurais/genética , Proteínas Proto-Oncogênicas c-akt/genética , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
5.
Am J Orthod Dentofacial Orthop ; 138(2): 188-94, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20691360

RESUMO

INTRODUCTION: The development of incipient caries, or white spot lesions (WSLs), is a significant clinical problem in orthodontics. The purpose of this study was to retrospectively determine the incidence and severity of WSLs by examining pretreatment and posttreatment digital photographs. METHODS: A total of 332 consecutive finished patients from a university graduate orthodontic clinic were evaluated. Initial and final digital images were compared to assess WSLs. The facial surfaces of the anterior 8 maxillary teeth were analyzed. The percentage area of WSL per total facial tooth surface was calculated to control for magnification differences. Reliability of the method was assessed by comparison with direct clinical examination data. Patient and operator factors, and treatment complexity and outcomes were evaluated as predictors of WSL incidence and severity. RESULTS: Agreement between direct clinical examination and digital photo data was excellent, with an intraclass correlation coefficient 0.88 and a 0.3% average difference between methods. The incidence of at least 1 WSL on the labial surface of the anterior 8 maxillary teeth was 36%. The order of incidence was lateral incisor (34%), canine (31%), premolar (28%), and central incisor (17%). CONCLUSIONS: Risk factors for the development of incipient caries during orthodontic treatment were young age (preadolescent) at the start of treatment, number of poor hygiene citations during treatment, unfavorable clinical outcome score, white ethnic group, and inadequate oral hygiene at the initial pretreatment examination. The use of computer software to evaluate digital photos retrospectively is a valid method for assessing the incidence and severity of WSLs on the maxillary anterior incisors, canines, and premolars.


Assuntos
Cárie Dentária/etiologia , Aparelhos Ortodônticos/efeitos adversos , Adolescente , Adulto , Fatores Etários , Dente Pré-Molar/patologia , Criança , Dente Canino/patologia , Cárie Dentária/patologia , Suscetibilidade à Cárie Dentária , Feminino , Humanos , Incisivo/patologia , Masculino , Maxila , Pessoa de Meia-Idade , Fotografia Dentária , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Fatores de Tempo , Adulto Jovem
6.
Transl Oncol ; 1(3): 129-40, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18795123

RESUMO

Malignant pleural mesothelioma (MPM) is an aggressive malignancy tightly associated with asbestos exposure. The increasing incidence of MPM and its resistance to all therapeutic modalities necessitate an urgent development of new treatments for MPM. Proteasome inhibitors (PIs) have emerged as promising agents for treating human cancers that are refractory to current chemotherapies. In this study, we characterized MG132, a commonly used PI, for its proapoptotic and anti-invasion activities in NCI-H2452 and NCI-H2052 human thoracic MPM cell lines to determine the therapeutic effect of PIs on MPM. We found that as low as 0.5 microM MG132 caused a significant apoptosis in both cell lines as evidenced by DNA damage, cleavage of poly ADP-ribose polymerase and caspases 3, 7, and 9, and mitochondrial release of Smac/DIABLO and Cytochrome c. Mitochondrial caspase activation was found to be the underlying mechanism of the MG132-induced apoptosis. Mcl-1, among the Bcl-2 and IAP (inhibitor of apoptosis protein) antiapoptotic family proteins tested, was proved to be a major inhibitor of the MG132-induced apoptosis in MPM cells. Meanwhile, subapoptotic doses of MG132 inhibited the invasion of both MPM cell lines through reducing Rac1 activity. These observations demonstrate that MG132 possesses proapoptotic and anti-invasion activities in human MPM cells, therefore encouraging further investigations on the value of PIs for treating MPM.

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