Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Environ Qual ; 44(4): 1210-5, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26437102

RESUMO

Carbon dioxide off-setting policy in the agricultural sector is focused on manipulating the terrestrial carbon cycle by reafforestation and increasing the retention of carbon within agricultural soils. We quantified the amount of carbon stored in the living and dead biomass and the surface soils of a previously grazed woodland ecosystem. We demonstrate that modification of coarse woody debris management could potentially store 8 to 15 t C ha. This large carbon pool raises the prospect that appropriate management of temperate woodlands to retain coarse woody debris and increase its volume into the future could achieve increased landscape carbon storage.

2.
Oncogene ; 31(31): 3597-606, 2012 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-22120710

RESUMO

Aneuploidy is frequently detected in solid tumors but the mechanisms regulating the generation of aneuploidy and their relevance in cancer initiation remain under debate and are incompletely characterized. Spatial and temporal regulation of integrin traffic is critical for cell migration and cytokinesis. Impaired integrin endocytosis, because of the loss of Rab21 small GTPase or mutations in the integrin ß-subunit cytoplasmic tail, induces failure of cytokinesis in vitro. Here, we describe that repeatedly failed cytokinesis, because of impaired traffic, is sufficient to trigger the generation of aneuploid cells, which display characteristics of oncogenic transformation in vitro and are tumorigenic in vivo. Furthermore, in an in vivo mouse xenograft model, non-transformed cells with impaired integrin traffic formed tumors with a long latency. More detailed investigation of these tumors revealed that the tumor cells were aneuploid. Therefore, abnormal integrin traffic was linked with generation of aneuploidy and cell transformation also in vivo. In human prostate and ovarian cancer samples, downregulation of Rab21 correlates with increased malignancy. Loss-of-function experiments demonstrate that long-term depletion of Rab21 is sufficient to induce chromosome number aberrations in normal human epithelial cells. These data are the first to demonstrate that impaired integrin traffic is sufficient to induce conversion of non-transformed cells to tumorigenic cells in vitro and in vivo.


Assuntos
Aneuploidia , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Citocinese , Integrinas/metabolismo , Animais , Mama/metabolismo , Regulação para Baixo , Células Epiteliais/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Transporte Proteico/fisiologia , Proteínas rab de Ligação ao GTP/biossíntese , Proteínas rab de Ligação ao GTP/genética
3.
Oncogene ; 29(49): 6452-63, 2010 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-20802519

RESUMO

The majority of mortality associated with cancer is due to formation of metastases from the primary tumor. Adhesion mediated by different integrin heterodimers has an important role during cell migration and invasion. Protein interactions with the ß1-integrin cytoplasmic tail are known to influence integrin affinity for extracellular ligands, but regulating binding partners for the α-subunit cytoplasmic tails have remained elusive. In this study, we show that mammary-derived growth inhibitor (MDGI) (also known as FABP-3 or H-FABP) binds directly to the cytoplasmic tail of integrin α-subunits and its expression inhibits integrin activity. In breast cancer cell lines, MDGI expression correlates with suppression of the active conformation of integrins. This results in reduced integrin adhesion to type I collagen and fibronectin and inhibition of cell migration and invasion. In tissue microarray of 1331 breast cancer patients, patients with MDGI-positive tumors had more favorable 10-year distant disease-free survival compared with patients with MDGI-negative tumors. Our data indicate that MDGI is a novel interacting partner for integrin α-subunits, and its expression modulates integrin activity and suppresses cell invasion in breast cancer patients. Retained MDGI expression is associated with favorable prognosis.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Proteínas de Ligação a Ácido Graxo/metabolismo , Cadeias alfa de Integrinas/metabolismo , Sequência de Aminoácidos , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Colágeno Tipo I/metabolismo , Intervalo Livre de Doença , Matriz Extracelular/química , Proteína 3 Ligante de Ácido Graxo , Feminino , Fibronectinas/metabolismo , Humanos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Invasividade Neoplásica , Domínios e Motivos de Interação entre Proteínas
4.
Physiol Meas ; 27(10): 1047-56, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16951463

RESUMO

Snoring is a prevalent condition with a variety of negative social effects and associated health problems. Treatments, both surgical and therapeutic, have been developed, but the objective non-invasive monitoring of their success remains problematic. We present a method which allows the automatic monitoring of snoring characteristics, such as intensity and frequency, from audio data captured via a freestanding microphone. This represents a simple and portable diagnostic alternative to polysomnography. Our system is based on methods that have proved effective in the field of speech recognition. Hidden Markov models (HMMs) were employed as basic elements with which to model different types of sound by means of spectrally based features. This allows periods of snoring to be identified, while rejecting silence, breathing and other sounds. Training and test data were gathered from six subjects, and annotated appropriately. The system was tested by requiring it to automatically classify snoring sounds in new audio recordings and then comparing the result with manually obtained annotations. We found that our system was able to correctly identify snores with 82-89% accuracy, despite the small size of the training set. We could further demonstrate how this segmentation can be used to measure the snoring intensity, snoring frequency and snoring index. We conclude that a system based on hidden Markov models and spectrally based features is effective in the automatic detection and monitoring of snoring from audio data.


Assuntos
Ronco/diagnóstico , Acústica , Adulto , Idoso , Feminino , Humanos , Masculino , Cadeias de Markov , Pessoa de Meia-Idade , Polissonografia/métodos
5.
Dysphagia ; 14(3): 157-61, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10341113

RESUMO

The present study aimed to investigate the effects of different-sized nasogastric tubes on swallowing speed and function in 10 young normal volunteers. Using X-ray visualization, liquid barium swallows were recorded on video (videofluoroscopy) under three experimental conditions: no nasogastric tube, fine-bore nasogastric tube, and wide-bore nasogastric tube. Nasogastric tubes slowed swallowing but did not alter swallowing function, namely bolus transit and clearance, and airway protection. The presence of a wide-bore nasogastric tube caused significant duration changes in several swallowing measures, namely duration of stage transition, duration of pharyngeal response, duration of pharyngeal transit, and duration of upper esophageal sphincter opening. Similar trends were seen for the fine-bore tube. The implications for nonoral feeding of patients with swallowing disorders are discussed.


Assuntos
Transtornos de Deglutição/etiologia , Intubação Gastrointestinal/efeitos adversos , Adulto , Cinerradiografia/métodos , Transtornos de Deglutição/diagnóstico por imagem , Feminino , Humanos , Masculino , Distribuição Aleatória , Fatores de Tempo
8.
Folia Phoniatr (Basel) ; 31(4): 242-9, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-544403
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...