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1.
Chem Sci ; 12(1): 239-246, 2020 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-34163592

RESUMEN

Heparanase (HPA) is a critical enzyme involved in the remodeling of the extracellular matrix (ECM), and its elevated expression has been linked with diseases such as various types of cancer and inflammation. The detection of heparanase enzymatic activity holds tremendous value in the study of the cellular microenvironment, and search of molecular therapeutics targeting heparanase, however, no structurally defined probes are available for the detection of heparanase activity. Here we present the development of the first ultrasensitive fluorogenic small-molecule probe for heparanase enzymatic activity via tuning the electronic effect of the substrate. The probe exhibits a 756-fold fluorescence turn-on response in the presence of human heparanase, allowing one-step detection of heparanase activity in real-time with a picomolar detection limit. The high sensitivity and robustness of the probe are exemplified in a high-throughput screening assay for heparanase inhibitors.

2.
Sci Rep ; 9(1): 2102, 2019 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-30765819

RESUMEN

Detection of cellular senescence is important not only in the study of senescence in various biological systems, but also in various practical applications such as image-guided surgical removal of senescent cells, as well as the monitoring of drug-responsiveness during cancer therapies. Due to the lack of suitable imaging probes for senescence detection, particularly in living subjects, we have developed an activatable near-infrared (NIR) molecular probe with far-red excitation, NIR emission, and high "turn-on" ratio upon senescence-associated ß-galactosidase (SABG) activation. We present here the first successful demonstration of NIR imaging of DNA damage-induced senescence both in vitro and in human tumor xenograft models.


Asunto(s)
Senescencia Celular , Neoplasias del Colon/patología , Daño del ADN , Procesamiento de Imagen Asistido por Computador/métodos , Microscopía Fluorescente/métodos , Animales , Apoptosis , Proliferación Celular , Neoplasias del Colon/genética , Femenino , Colorantes Fluorescentes , Humanos , Ratones , Ratones Desnudos , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
3.
FASEB J ; 23(12): 4256-65, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19703933

RESUMEN

The distinct lack of cell lines derived from the adult brain is evident. Ciliary neurotrophic factor (CNTF) triggers neurogenesis in primary culture from adult mouse hypothalamus, as detected by bromodeoxyuridine and Ki67 immunostaining. Using SV-40 T-antigen, we immortalized dividing neurons and generated clonal cell lines expressing neuropeptides and receptors involved in neuroendocrine function. We hypothesized that proglucagon-derived peptides may be the mechanistic downstream effectors of CNTF due to documented neuroprotective and proliferative effects. Indeed, proglucagon gene expression was induced by CNTF, and exposure of primary cells to glucagon-like peptide-1 receptor (GLP-1) agonist, exendin-4, induced cell proliferation. Intracerebroventricular injection of CNTF into adult mice caused increased expression of proglucagon peptide in the hypothalamus. Using a specific GLP-1-receptor antagonist, we found that neurogenesis was significantly attenuated and primary culture from GLP-1-receptor-knockout mice lacked CNTF-mediated neuronal proliferation, thus linking the induction of neurogenesis in the hypothalamus to GLP-1-receptor signaling.


Asunto(s)
Factor Neurotrófico Ciliar/farmacología , Péptido 1 Similar al Glucagón/metabolismo , Hipotálamo/citología , Neurogénesis/fisiología , Neuronas/citología , Animales , Línea Celular , Proliferación Celular , Factor Neurotrófico Ciliar/metabolismo , Regulación de la Expresión Génica , Masculino , Ratones , Ratones Endogámicos C57BL , Proglucagón/genética , Proglucagón/metabolismo , Transducción de Señal
4.
Eur Respir J ; 22(3): 497-502, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14516141

RESUMEN

Neutrophil-dominated endobronchial inflammation is a major characteristic of cystic fibrosis (CF) and there is increasing demand for easy-to-perform noninvasive monitoring for prediction and intervention. Fourteen stable paediatric CF patients (8-17 yrs; mean forced expiratory volume in one second 86.7% of the predicted value) were investigated once by fractional bronchoalveolar lavage (BAL) and by sputum induction on three occasions, 2-6 weeks apart. Sputum was induced by consecutive 10-min inhalations of 3, 4 and 5% saline. CF sputum cellular profiles were compared with BAL fluid cell counts and samples from age-matched healthy children, and between different time points to assess reproducibility. Adequate sputum was recovered on >95% of occasions. In all sputum fractions, CF patients showed higher neutrophil counts than healthy children. Neutrophil percentages were highest in the first BAL fraction (median 92%), followed by sputum, in which the percentages decreased in consecutive fractions (72, 66 and 64%), whereas counts were lowest in the pooled BAL fraction (53%). Increasing percentages of macrophages mirrored the decreases in neutrophil percentage. Results of sputum induction at different time points in the CF patients showed good reproducibility and nonoverlap with counts from healthy children. In conclusion, the results of sputum induction in children with mild stable cystic fibrosis adequately describe airway inflammation by providing cellular profiles with lower relative neutrophil counts than in the first ("bronchial") bronchoalveolar lavage fraction and higher relative neutrophil counts than in subsequent pooled ("more peripheral") bronchoalveolar lavage fractions.


Asunto(s)
Líquido del Lavado Bronquioalveolar/citología , Fibrosis Quística/patología , Esputo/citología , Adolescente , Pruebas de Provocación Bronquial , Estudios de Casos y Controles , Recuento de Células , Niño , Fibrosis Quística/diagnóstico , Femenino , Humanos , Macrófagos , Masculino , Neutrófilos , Reproducibilidad de los Resultados
6.
Respir Med ; 91(6): 369-72, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9282240

RESUMEN

The results of pulmonary function testing with a turbine spirometer (TS) and a bell spirometer (BS) of a randomized group of 275 patients aged 4-18 years were compared. In the TS, an inexpensive device without graphical display was used. The difference BS minus TS (d) for forced expiratory volume in 1 s (FEV1) was calculated. The results indicate that the FEV1 might be overestimated by the TS, and that the difference of the readings of FEV1 between the spirometers increases with airway obstruction. The TS should be used with caution in young patients with asthma.


Asunto(s)
Asma/fisiopatología , Espirometría/instrumentación , Adolescente , Niño , Preescolar , Estudios de Evaluación como Asunto , Humanos , Pruebas de Función Respiratoria/instrumentación
7.
Metabolism ; 46(6): 619-24, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9186295

RESUMEN

It has previously been shown that the n-3 polyunsaturated fatty acids (PUFAs) eicosapentaenoic acid (20:5(n-3)) and docosahexaenoic acid (22:6(n-3)) possess antiinflammatory properties and can interfere with immune functions. To evaluate whether this would affect resistance to infection, we studied the influence of different types of fatty acids (FAs) on experimental tuberculosis in an animal model. Three groups of 26 weanling guinea pigs were fed isocaloric diets with 26 cal% fat that differed in FA composition with respect to saturated FAs, linoleic acid (18:2(n-6)), eicosapentaenoic acid (20:5(n-3)), and docosanexaenoic acid (22:6(n-3)) as follows: (1) reference (REF) group: 14.8 cal% saturated FAs and 2.8 cal% linoleic acid; (2) n-6 group: 4.6 cal% saturated FAs and 15.4 cal% linoleic acid; (3) n-3 group: 6.3 cal% saturated FAs, 10 cal% linoleic acid, 1.4 cal% eicosapentaenoic acid, and 0.9 cal% docosahexaenoic acid. After 13 weeks, 18 animals from each group were intramuscularly injected with 180 colony-forming units (CFU) Mycobacterium tuberculosis strain H37Rv. Eight noninfected animals per group served as controls. Seven weeks later, the mean number of mycobacteria recovered from the spleens of the n-3 group (log 4.34 CFU, standard error of the mean [SEM], 0.12) was significantly higher than from the REF group (log 3.90 CFU; SEM, 0.15) and the n-8 group (log 3.93 CFU; SEM, 0.13; P < .05). In addition, the Root Index of Virulence (RIV) showed the most pronounced progression of the disease in the n-3 group. The mean size of the tuberculin reaction was larger in the n-3 group than in the other groups (P < .05). There was no significant difference between the n-6 group and the REF group. We conclude that supplementing the diet with n-3 FAs eicosapentaenoic acid and docosahexaenoic acid can affect resistance to M tuberculosis, whereas supplementing with n-6 FAs does not.


Asunto(s)
Grasas Insaturadas en la Dieta/farmacología , Ácidos Grasos Omega-3/farmacología , Ácidos Grasos Insaturados/farmacología , Tuberculosis/fisiopatología , Animales , Ingestión de Energía , Ácidos Grasos no Esterificados/sangre , Ácidos Grasos Omega-6 , Cobayas , Inmunidad Innata , Masculino , Mycobacterium tuberculosis/aislamiento & purificación , Pruebas Cutáneas , Bazo/microbiología , Tuberculosis/inmunología , Aumento de Peso
8.
Am Rev Respir Dis ; 143(4 Pt 1): 876-9, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2008998

RESUMEN

Respiratory distress developed in a 5-month-old female infant with roentgenographic evidence of hyperinflation of the right lung. Bronchoscopy revealed a vascular tumor extending from the medial wall of the right main bronchus leading to a check-valve mechanism. Radionuclide lung scans showed ventilation and perfusion of the right side reduced to 36 and 11% of the total lung ventilation and perfusion, respectively. At the age of 7 months a sleeve of the right main bronchus was resected and a reanastomosis performed. The operation specimen contained a capillary hemangioma measuring 1.2 X 0.6 cm. The postoperative course was uneventful. Perfusion of the right lung had markedly improved 6 months after the operation, and at the age of 2 yr and 9 months it was completely normal. Capillary hemangiomas must be considered a cause of bronchial obstruction in infancy, and surgery can be performed successfully.


Asunto(s)
Neoplasias de los Bronquios/cirugía , Hemangioma/cirugía , Bronquios/cirugía , Neoplasias de los Bronquios/diagnóstico por imagen , Neoplasias de los Bronquios/patología , Femenino , Hemangioma/diagnóstico por imagen , Hemangioma/patología , Humanos , Lactante , Métodos , Radiografía
9.
Eur J Pediatr ; 149(12): 862-5, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2226573

RESUMEN

Pulmonary function was evaluated before and after 15 operations for resection of pulmonary metastases from osteogenic sarcoma. In the whole study group (ten patients, aged 13-18 years) preoperative vital capacity (VC) ranged from 62% to 122% (mean 83%) of predicted normal values for height. The operations were performed via median sternotomy. One-28 metastases were removed per session. Six months after the operations VC averaged nearly 95% of the preoperative values. Signs of bronchial obstruction or persistent pulmonary hyperinflation were only present in one patient with repeated operations. We conclude that resection of pulmonary metastases with limited loss of parenchyma leads to an almost complete recovery of preoperative pulmonary function parameters.


Asunto(s)
Neoplasias Pulmonares/cirugía , Mediciones del Volumen Pulmonar , Pulmón/fisiología , Osteosarcoma/cirugía , Adolescente , Neoplasias Óseas/patología , Femenino , Humanos , Neoplasias Pulmonares/secundario , Masculino , Osteosarcoma/secundario , Pronóstico , Estudios Retrospectivos , Capacidad Vital
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