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1.
Ann Bot ; 127(7): 919-929, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-33640955

RESUMO

BACKGROUND AND AIMS: Plants in dry Mediterranean mountains experience a double climatic stress: at low elevations, high temperatures coincide with water shortage during summer, while at high elevations temperature decreases and water availability increases. Cushion plants often act as nurses by improving the microclimate underneath their canopies, hosting beneficiary species that may reciprocally modify their benefactors' microenvironment. We assess how the nurse cushion plant Arenaria tetraquetra subsp. amabilis adjusts its hydraulic system to face these complex abiotic and biotic constraints. METHODS: We evaluated intra-specific variation and co-ordination of stem xylem anatomy, leaf functional traits and plant architecture in response to elevation, aspect and the presence of beneficiary species in four A. tetraquetra subsp. amabilis populations in the Sierra Nevada mountains, southern Spain. KEY RESULTS: Xylem anatomical and plant architectural traits were the most responsive to environmental conditions, showing the highest mutual co-ordination. Cushions were more compact and had smaller, more isolated conductive vessels in the southern than in the northern aspect, which allow minimization of the negative impacts of more intense drought. Only vessel size, leaf mass per area and terminal branch length varied with elevation. Nurse cushions co-ordinated plant architecture and xylem traits, having higher canopy compactness, fewer leaves per branch and fewer, more isolated vessels than non-nurse cushions, which reflects the negative effects of beneficiary plants on nurse water status. In non-nurse cushions, plant architecture co-ordinated with leaf traits instead. The interacting effects of aspect and elevation on xylem traits showed that stress due to frost at high elevation constrained xylem anatomy in the north, whereas stress due to drought had a parallel effect in the south. CONCLUSIONS: Trait co-ordination was weaker under more demanding environmental conditions, which agrees with the hypothesis that trait independence allows plants to better optimize different functions, probably entailing higher adjustment potential against future environmental changes.


Assuntos
Árvores , Xilema , Secas , Folhas de Planta , Plantas , Água
2.
Am J Surg ; 218(5): 993-999, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30665612

RESUMO

BACKGROUND: Hypocalcemia is one of the most common complications after total thyroidectomy. Recently, indocyanine green (ICG) angiography of the parathyroid glands (PGs) has been suggested as a reliable tool for predicting postoperative hypocalcemia. The aim of our study was to evaluate the performance of a simple quantitative score based on ICG angiography of the PGs (4-ICG score) for predicting postoperative hypocalcemia. METHODS: Thirty nine consecutive patients who underwent total thyroidectomy for multinodular goiter were included. For each patient, the 4-ICG score was calculated, adding the individual viability value of the four PGs. Discrimination and correlation analyses were performed. RESULTS: In 32/39 patients, the four PGs were identified. Patients with postoperative hypocalcemia (n = 6, 19%) had a lower 4-ICG score (2.5 [1.8-3.3] vs. 4.0 [3.0-6.0]; p = 0.003). The 4-ICG score showed good discrimination in terms of predicting postoperative hypocalcemia (AUC = 0.875 (0.710-0.965); p = 0.001) and a good correlation with postoperative parathyroid function. CONCLUSIONS: The 4-ICG score predicts postoperative hypocalcemia and correlates well with postoperative parathyroid function in patients undergoing total thyroidectomy for multinodular goiter.


Assuntos
Angiografia/métodos , Hipocalcemia/etiologia , Glândulas Paratireoides/irrigação sanguínea , Glândulas Paratireoides/diagnóstico por imagem , Tireoidectomia/efeitos adversos , Adulto , Idoso , Corantes , Feminino , Humanos , Verde de Indocianina , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes
3.
J Clin Endocrinol Metab ; 91(9): 3639-46, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16804051

RESUMO

CONTEXT: T regulatory cells have a key role in the pathogenesis of autoimmune diseases in different animal models. However, less information is available regarding these cells in human autoimmune thyroid diseases (AITD). OBJECTIVE: The objective of the study was to analyze different regulatory T cell subsets in patients with AITD. DESIGN: We studied by flow cytometry and immunohistochemistry different T regulatory cell subsets in peripheral blood mononuclear cells (PBMCs) and thyroid cell infiltrates from 20 patients with AITD. In addition, the function of T(REG) lymphocytes was assessed by cell proliferation assays. Finally, TGF-beta mRNA in thyroid tissue and its in vitro synthesis by thyroid mononuclear cells (TMCs) was determined by RNase protection assay and quantitative PCR. RESULTS: PBMCs from AITD patients showed an increased percent of CD4+ lymphocytes expressing glucocorticoid-induced TNF receptor (GITR), Foxp3, IL-10, TGF-beta, and CD69 as well as CD69+CD25(bright), CD69+TGF-beta, and CD69+IL-10+ cells, compared with controls. TMCs from these patients showed an increased proportion of CD4+GITR+, CD4+CD69+, and CD69+ cells expressing CD25(bright), GITR, and Foxp3, compared with autologous PBMCs. Furthermore, a prominent infiltration of thyroid tissue by CD69+, CD25+, and GITR+ cells, with moderate levels of Foxp3+ lymphocytes, was observed. The suppressive function of peripheral blood T(REG) cells was defective in AITD patients. Finally, increased levels of TGF-beta mRNA were found in thyroid tissue, and thyroid cell infiltrates synthesized in vitro significant levels of TGF-beta upon stimulation through CD69. CONCLUSIONS: Although T regulatory cells are abundant in inflamed thyroid tissue, they are apparently unable, in most cases, to downmodulate the autoimmune response and the tissue damage seen in AITD.


Assuntos
Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Tireoidite Autoimune/imunologia , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Citometria de Fluxo , Fatores de Transcrição Forkhead/imunologia , Proteína Relacionada a TNFR Induzida por Glucocorticoide , Humanos , Imuno-Histoquímica , Imunofenotipagem , Interleucina-10/imunologia , Lectinas Tipo C , Ativação Linfocitária , RNA Mensageiro/genética , Receptores de Fator de Crescimento Neural/imunologia , Receptores do Fator de Necrose Tumoral/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Subpopulações de Linfócitos T/citologia , Linfócitos T Reguladores/citologia , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/imunologia
4.
Actas dermo-sifiliogr. (Ed. impr.) ; 96(1): 30-36, ene.-feb. 2005. ilus
Artigo em Es | IBECS | ID: ibc-037569

RESUMO

Introducción. Aunque el 65 % de las muertes causadas por cáncer de piel son debidas a melanomas, todavía se desconocen las posibles causas que puedan explicar la agresividad de este tipo de tumor. Se han utilizado distintos abordajes con el fin de encontrar una terapia efectiva, pero sin éxito. El ARN de interferencia (ARNi) es una técnica imprescindible para la investigación. Con esta técnica podemos silenciar selectivamente la expresión de proteínas (knockdown). Las tetraspaninas CD9 y CD151 son moléculas implicadas en la motilidad celular, incluidas las células de melanoma. Material y métodos. Línea de melanoma A375, anticuerpos monoclonales anti-CD9 y anti-CD151, y ARNi para CD9 y CD151. Técnicas de inmunofluorescencia, citometría de flujo, transfección celular, selección celular con bolas magnéticas y evaluación de la migración celular en modelo de curación de heridas. Resultados. Las células A375 expresan CD9 y CD151. Utilizando ARNi de CD9 y CD151 se ha conseguido inhibir la expresión de estas proteínas. Las células transfectadas con ARNi de CD9 mostraron una inhibición significativa de su motilidad. Discusión. Nosotros hemos conseguido silenciar la expresión de CD9 y CD151 usando técnicas de ARNi en la línea celular de melanoma A375. La reducción de CD9 produjo una inhibición de la motilidad celular, mientras que la interferencia de la expresión de CD151 tuvo un efecto más moderado. Estos datos apuntan a que el silenciamiento de tetraspaninas puede ser en un futuro una diana para el tratamiento del melanoma


Introduction. Although 65 % of the deaths caused by skin cancer are due to melanomas, the possible causes that may explain the aggressiveness of this type of tumor are still unknown. Different approaches have been used to try to find an effective treatment, but they have been unsuccessful. Interference RNA (iRNA) is an essential technique for this research. With this technique, we can selectively «knock down» or silence protein expression. The tetraspanins CD9 and CD151 are molecules involved in cell motility, including melanoma cells. Material and methods. A375 melanoma cell line, anti-CD9 and anti-CD151 monoclonal antibodies, and iRNA against CD9 and CD151. Immunofluorescence techniques, flow cytometry, cell transfection, cell selection with magnetic beads and evaluation of cell migration in a wound-healing model. Results. The A375 cells express CD9 and CD151. By using iRNA against CD9 and CD151, we managed to inhibit the expression of these proteins. The cells transfected with iRNA against CD9 showed significant inhibition of their motility. Discussion. We managed to silence the expression of CD9 and CD151 using iRNA techniques in the A375 melanoma cell line. The reduction in CD9 caused the inhibition of cell motility, while the interference with CD151 expression had a more moderate effect. This data indicates that the knockdown of tetraspanins may be a future target for the treatment of melanoma


Assuntos
Masculino , Feminino , Camundongos , Animais , Movimento Celular/imunologia , Movimento Celular , Melanoma/diagnóstico , Melanoma/terapia , RNA/metabolismo , Anticorpos Monoclonais/análise , Anticorpos Monoclonais/metabolismo , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/terapia , Melanoma/patologia , Integrinas/análise , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais , Anticorpos Monoclonais/isolamento & purificação
5.
Actas Dermosifiliogr ; 96(1): 30-6, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-16476329

RESUMO

INTRODUCTION: Although 65 % of the deaths caused by skin cancer are due to melanomas, the possible causes that may explain the aggressiveness of this type of tumor are still unknown. Different approaches have been used to try to find an effective treatment, but they have been unsuccessful. Interference RNA (iRNA) is an essential technique for this research. With this technique, we can selectively "knock down" or silence protein expression. The tetraspanins CD9 and CD151 are molecules involved in cell motility, including melanoma cells. MATERIAL AND METHODS: A375 melanoma cell line, anti-CD9 and anti-CD151 monoclonal antibodies, and iRNA against CD9 and CD151. Immunofluorescence techniques, flow cytometry, cell transfection, cell selection with magnetic beads and evaluation of cell migration in a wound-healing model. RESULTS: The A375 cells express CD9 and CD151. By using iRNA against CD9 and CD151, we managed to inhibit the expression of these proteins. The cells transfected with iRNA against CD9 showed significant inhibition of their motility. DISCUSSION: We managed to silence the expression of CD9 and CD151 using iRNA techniques in the A375 melanoma cell line. The reduction in CD9 caused the inhibition of cell motility, while the interference with CD151 expression had a more moderate effect. This data indicates that the knockdown of tetraspanins may be a future target for the treatment of melanoma.


Assuntos
Antígenos CD/fisiologia , Movimento Celular/fisiologia , Melanoma/genética , Glicoproteínas de Membrana/fisiologia , Interferência de RNA/fisiologia , Neoplasias Cutâneas/genética , Antígenos CD/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Humanos , Melanoma/patologia , Glicoproteínas de Membrana/genética , Neoplasias Cutâneas/patologia , Tetraspanina 24 , Tetraspanina 29
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