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1.
Br J Cancer ; 108(2): 351-60, 2013 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-23299531

RESUMEN

BACKGROUND: Tissue protein expression profiling has the potential to detect new biomarkers to improve breast cancer (BC) diagnosis, staging, and prognostication. This study aimed to identify tissue proteins that differentiate breast cancer tissue from healthy breast tissue using protein chip mass spectrometry and to examine associations with conventional pathological features. METHODS: To develop a training model, 82 BC and 82 adjacent unaffected tissue (AT) samples were analysed on cation-exchange protein chips by time-of-flight mass spectrometry. For validation, 89 independent BC and AT sample pairs were analysed. RESULTS: From the protein peaks that were differentially expressed between BC and AT by univariate analysis, binary logistic regression yielded two peaks that together classified BC and AT with a ROC area under the curve of 0.92. Two proteins, ubiquitin and S100P (in a novel truncated form), were identified by liquid chromatography/tandem mass spectrometry and validated by immunoblotting and reactive-surface protein chip immunocapture. The combined marker panel was positively associated with high histologic grade, larger tumour size, lymphovascular invasion, ER and PR positivity, and HER2 overexpression, suggesting that it may be associated with a HER2-enriched molecular subtype of breast cancer. CONCLUSION: This independently validated protein panel may be valuable in the classification and prognostication of breast cancer patients.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias de la Mama/diagnóstico , Proteínas de Neoplasias/análisis , Proteómica/métodos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/química , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Proteínas de Unión al Calcio/análisis , Femenino , Humanos , Metástasis Linfática , Persona de Mediana Edad , Pronóstico , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Ubiquitina/análisis
2.
Bull Math Biol ; 74(12): 2820-41, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23081729

RESUMEN

The paper presents a modeling study of the spatial dynamics of a nephro-vascular network consisting of individual nephrons connected via a tree-like vascular branching structure. We focus on the effects of nonlinear mechanisms that are responsible for the formation of synchronous patterns in order to learn about processes not directly amenable to experimentation. We demonstrate that: (i) the nearest nephrons are synchronized in-phase due to a vascular propagated electrical coupling, (ii) the next few branching levels display a formation of phase-shifted patterns due to hemodynamic coupling and mode elimination, and (iii) distantly located areas show asynchronous behavior or, if all nephrons and branches are perfectly identical, an infinitely long transient behavior. These results contribute to the understanding of mechanisms responsible for the highly dynamic and limited synchronization observed among groups of nephrons despite of the fairly strong interaction between the individual units.


Asunto(s)
Modelos Biológicos , Nefronas/irrigación sanguínea , Nefronas/fisiología , Animales , Fenómenos Electrofisiológicos , Hemodinámica , Conceptos Matemáticos , Modelos Anatómicos , Nefronas/crecimiento & desarrollo , Oscilometría
3.
Intern Med J ; 41(9): 695-9, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21899683

RESUMEN

Parathyroid carcinoma, although a rare cause of primary hyperparathyroidism, carries a significant morbidity and mortality from severe symptomatic hypercalcaemia and related complications. We report a case where the diagnosis was not considered from the outset and review the current clinical and histopathological markers available to assist in the diagnosis of parathyroid carcinoma.


Asunto(s)
Adenoma/diagnóstico , Biomarcadores de Tumor/fisiología , Errores Diagnósticos , Neoplasias de las Paratiroides/diagnóstico , Proteínas Supresoras de Tumor/fisiología , Adenoma/sangre , Adulto , Biomarcadores de Tumor/sangre , Femenino , Humanos , Neoplasias de las Paratiroides/sangre , Neoplasias de las Paratiroides/secundario , Proteínas Supresoras de Tumor/sangre
4.
J Plast Reconstr Aesthet Surg ; 64(4): 535-40, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20708986

RESUMEN

INTRODUCTION: Toe syndactyly affects around 1/2000 people and is associated with significant psychological morbidity. There are multiple techniques of toe syndactyly repair described in the literature which is indicative that as yet, no one method has proved superior to others. Here we describe the technique we employ and present results of surgery including a review of patient satisfaction. METHODS: We use a modification of the technique originally described by Mondolfi using interdigitating triangular skin flaps to recreate the web space and a split thickness skin graft harvested from the instep to address the skin shortage. Patient satisfaction data were collected using a multiple response 10 point modified Likert scale questionnaire. RESULTS: 15 patients and 19 conjoined toes were operated on by a single surgeon with an average follow up time of 16.3 months (range 3-30 months). Overall satisfaction with the procedure was high with a significant increase in satisfaction from 1.3/10 preoperatively to 9.3/10 post operatively. Furthermore, patients were found to have a significant reduction in concern about their condition from a preoperative score of 8.67 to score of 0.67 following surgery (p < 0.05). Of the 19 toes divided, we had 1 skin graft failure, 1 case of mild web creep and all donor sites healed well. CONCLUSIONS: This is a simple technique that avoids unsightly dorsal scars and the glabrous skin graft provides excellent colour match with minimal morbidity. Complication rates seen with this technique are comparable or superior to those seen with other techniques already described in the literature. Toe syndactyly can be a relatively under treated condition and we have shown that offering these patients surgery can result in a highly satisfied patient group.


Asunto(s)
Sindactilia/cirugía , Dedos del Pie/anomalías , Dedos del Pie/cirugía , Adolescente , Adulto , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Satisfacción del Paciente , Procedimientos de Cirugía Plástica/métodos , Colgajos Quirúrgicos , Adulto Joven
5.
Br J Pharmacol ; 159(2): 374-83, 2010 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-20015294

RESUMEN

BACKGROUND AND PURPOSE: Melanin-concentrating hormone (MCH) is an orexigenic neuropeptide expressed in the lateral hypothalamus that is involved in feeding and body weight regulation. Intracerebroventricular infusion of a peptidic MCH1 receptor antagonist ameliorated obesity in murine models. Recently, small molecule MCH1 receptor antagonists have been developed and characterized for the treatment of obesity. However, little is known of the mechanism of the anti-obesity effects of MCH1 receptor antagonists. EXPERIMENTAL APPROACH: To examine the mechanisms of action of the anti-obesity effect of MCH1 receptor antagonists more precisely, we conducted a pair-feeding study in mice with diet-induced obesity (DIO), chronically treated with an orally active and highly selective MCH1 receptor antagonist and examined changes in mRNA expression levels in liver, brown and white adipose tissues. We also assessed the acute effects of the MCH1 receptor antagonist in energy expenditure under thermoneutral conditions. KEY RESULTS: Treatment with the MCH1 receptor antagonist at 30 mg.kg(-1) for 1 month moderately suppressed feeding and significantly reduced body weight by 24%. In contrast, pair-feeding resulted in a smaller weight reduction of 10%. Treatment with the MCH1 receptor antagonist resulted in a higher body temperature compared with the pair-fed group. TaqMan and calorimetry data suggested that the MCH1 receptor antagonist also stimulated thermogenesis. CONCLUSIONS AND IMPLICATIONS: Our results indicate that an MCH1 receptor antagonist caused anti-obesity effects im mice by acting on both energy intake and energy expenditure.


Asunto(s)
Fármacos Antiobesidad/farmacología , Piridonas/farmacología , Pirrolidinas/farmacología , Receptores de Somatostatina/antagonistas & inhibidores , Tejido Adiposo Pardo/efectos de los fármacos , Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/efectos de los fármacos , Tejido Adiposo Blanco/metabolismo , Animales , Fármacos Antiobesidad/farmacocinética , Células CHO , Cricetinae , Cricetulus , Ingestión de Alimentos/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Humanos , Hígado/efectos de los fármacos , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Piridonas/farmacocinética , Pirrolidinas/farmacocinética , ARN Mensajero/biosíntesis , Ensayo de Unión Radioligante , Ratas , Receptores de Somatostatina/biosíntesis , Receptores de Somatostatina/genética , Termogénesis/efectos de los fármacos
6.
J Anim Sci ; 85(5): 1274-84, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17224462

RESUMEN

Embryonic and fetal mortality reduce lambing rates and litter sizes, thus contributing to economic losses in the sheep industry. In the current study, the timing of late embryonic and fetal loss in ewes and the factors with which these losses were associated were examined. Ewes lambing and lambs born were compared with pregnancy diagnosis and counts of embryos by ultrasonography near d 25, 45, 65, or 85 of gestation. Approximately 19.9% of the ewes experienced late embryonic loss, fetal loss, or both; and 21.2% of the embryos or fetuses were lost from d 25 to term. Potential offspring were lost throughout gestation; 3.7% of embryos from d 25 to 45, 4.3% of fetuses from d 45 to 65, 3.3% from d 65 to 85, and 11.5% from d 85 to parturition; thus, approximately 3 to 4% of the potential offspring were lost for each 20-d period of pregnancy beyond d 25. A greater proportion of ewes lost one (36.7%) rather than all (20.5% single; 3.8% multiple) embryos or fetuses. The patterns of loss were similar in ewes mated during the anestrous season and the transitional period and did not vary with service period within breeding season or method of synchronization of estrus. Late embryonic or fetal losses were not related to the temperature-humidity index. Maternal serum collected near d 25, 45, 65, or 85 of gestation was assayed for concentrations of progesterone, estradiol-17beta , and vascular endothelial growth factor (VEGF). The proportions of embryos or fetuses lost were associated with breed type (P < 0.05), as were concentrations of progesterone (P < 0.01), estradiol (P < 0.05), and VEGF (P < 0.01). The relationships of loss or retention of pregnancy to hormonal variables at the 4 stages studied were limited. Complete and partial losses increased rapidly as maternal progesterone at d 25 decreased below 2 ng/mL (P < 0.05). Survival of fetuses within a litter from d 25 to 65 was greater for ewes with medium concentrations of VEGF near d 25 and from d 65 to parturition was greater for ewes with high concentrations of VEGF near d 45 (P < 0.05). In summary, late embryonic or fetal losses occurred from d 25 throughout gestation and varied with breed type and with concentrations of progesterone in maternal serum on d 25.


Asunto(s)
Aborto Veterinario/etiología , Pérdida del Embrión/veterinaria , Muerte Fetal/veterinaria , Enfermedades de las Ovejas/etiología , Aborto Veterinario/sangre , Animales , Pérdida del Embrión/sangre , Pérdida del Embrión/etiología , Estradiol/sangre , Femenino , Muerte Fetal/sangre , Muerte Fetal/etiología , Embarazo , Progesterona/sangre , Factores de Riesgo , Estaciones del Año , Ovinos , Enfermedades de las Ovejas/sangre , Enfermedades de las Ovejas/genética , Factor A de Crecimiento Endotelial Vascular/sangre
7.
Chirurg ; 77(1): 15-24, 2006 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-16418876

RESUMEN

In contrast to primary hyperparathyroidism, parathyroid carcinoma is a rare disease. In patients with hyperparathyroidism jaw tumor (HPT-JT) syndrome, caused by germline mutations in HRPT2, the development of parathyroid carcinoma is estimated to be 10-15%. This review summarizes the clinical and molecular genetic data of about 100 patients in the literature and three of our own cases. Unfortunately, osteofibromas, which might enable timely diagnosis of HPT-JT syndrome, occur in only about 30% of patients; about 80% have uniglandular disease. Based on the current data, a general recommendation to perform prophylactic parathyroidectomy cannot be given. However, thorough screening of patients at risk is mandatory. Of note in patients thought to have sporadic parathyroid carcinoma, germline HRPT2 mutations are found in up to 20%. Hence, any patient with parathyroid carcinoma should undergo HRPT2 mutation analysis.


Asunto(s)
Hiperparatiroidismo Primario/genética , Hiperparatiroidismo Primario/cirugía , Neoplasias de las Paratiroides/genética , Neoplasias de las Paratiroides/prevención & control , Paratiroidectomía , Análisis Mutacional de ADN , Pruebas Genéticas , Humanos , Glándulas Paratiroides/patología , Medición de Riesgo , Síndrome
8.
Physiol Meas ; 26(4): 351-62, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15886431

RESUMEN

On the basis of double-wavelet analysis, the paper proposes a method to study interactions in the form of frequency and amplitude modulation in nonstationary multimode data series. Special emphasis is given to the problem of quantifying the strength of modulation for a fast signal by a coexisting slower dynamics and to its physiological interpretation. Application of the approach is demonstrated for a number of model systems, including a model that generates chaotic dynamics. The approach is then applied to proximal tubular pressure data from rat nephrons in order to estimate the degree to which the myogenic dynamics of the afferent arteriole is modulated by the slower tubulo-glomerular dynamics. Our analysis reveals a significantly stronger interaction between the two mechanisms in spontaneously hypertensive rats than in normotensive rats.


Asunto(s)
Algoritmos , Relojes Biológicos , Hipertensión Renal/fisiopatología , Modelos Biológicos , Nefronas/irrigación sanguínea , Nefronas/fisiopatología , Circulación Renal , Animales , Simulación por Computador , Retroalimentación , Modelos Estadísticos , Presión , Ratas , Procesos Estocásticos
9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 70(3 Pt 1): 031915, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15524557

RESUMEN

Biological time series often display complex oscillations with several interacting rhythmic components. Renal autoregulation, for instance, involves at least two separate mechanisms both of which can produce oscillatory variations in the pressures and flows of the individual nephrons. Using double-wavelet analysis we propose a method to examine how the instantaneous frequency and amplitude of a fast mode is modulated by the presence of a slower mode. Our method is applied both to experimental data from normotensive and hypertensive rats showing different oscillatory patterns and to simulation results obtained from a physiologically based model of the nephron pressure and flow control. We reveal a nonlinear interaction between the two mechanisms that regulate the renal blood flow in the form of frequency and amplitude modulation of the myogenic oscillations.


Asunto(s)
Algoritmos , Relojes Biológicos , Retroalimentación , Homeostasis , Hipertensión Renal/fisiopatología , Riñón/fisiopatología , Nefronas/fisiopatología , Adaptación Fisiológica , Animales , Simulación por Computador , Riñón/irrigación sanguínea , Modelos Biológicos , Nefronas/irrigación sanguínea , Ratas
17.
Endocrinology ; 145(6): 2607-12, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-14962995

RESUMEN

Ghrelin, a stomach-derived orexigenic hormone, has stimulated great interest as a potential target for obesity control. Pharmacological evidence indicates that ghrelin's effects on food intake are mediated by neuropeptide Y (NPY) and agouti-related protein (AgRP) in the central nervous system. These include intracerebroventricular application of antibodies to neutralize NPY and AgRP, and the application of an NPY Y1 receptor antagonist, which blocks some of the orexigenic effects of ghrelin. Here we describe treatment of Agrp(-/-);Npy(-/-) and Mc3r(-/-);Mc4r(-/-) double knockout mice as well as Npy(-/-) and Agrp(-/-) single knockout mice with either ghrelin or an orally active nonpeptide ghrelin agonist. The data demonstrate that NPY and AgRP are required for the orexigenic effects of ghrelin, as well as the involvement of the melanocortin pathway in ghrelin signaling. Our results outline a functional interaction between the NPY and AgRP pathways. Although deletion of either NPY or AgRP caused only a modest or nondetectable effect, ablation of both ligands completely abolished the orexigenic action of ghrelin. Our results establish an in vivo orexigenic function for NPY and AgRP, mediating the effect of ghrelin.


Asunto(s)
Apetito/fisiología , Neuropéptido Y/fisiología , Hormonas Peptídicas/fisiología , Proteínas/fisiología , Proteína Relacionada con Agouti , Animales , Apetito/efectos de los fármacos , Ghrelina , Péptidos y Proteínas de Señalización Intercelular , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Hormonas Peptídicas/farmacología , Receptor de Melanocortina Tipo 3/fisiología , Receptor de Melanocortina Tipo 4/fisiología , Receptores Acoplados a Proteínas G/fisiología , Receptores de Ghrelina
18.
J Med Genet ; 40(9): 657-63, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12960210

RESUMEN

BACKGROUND: Hyperparathyroidism is a common endocrinopathy characterised by the formation of parathyroid tumours. In this study, we determine the role of the recently identified gene, HRPT2, in parathyroid tumorigenesis. METHODS: Mutation analysis of HRPT2 was undertaken in 60 parathyroid tumours: five HPT-JT, three FIHP, three MEN 1, one MEN 2A, 25 sporadic adenomas, 17 hyperplastic glands, two lithium associated tumours, and four sporadic carcinomas. Loss of heterozygosity at 1q24-32 was performed on a subset of these tumours. RESULTS: HRPT2 somatic mutations were detected in four of four sporadic parathyroid carcinoma samples, and germline mutations were found in five of five HPT-JT parathyroid tumours (two families) and two parathyroid tumours from one FIHP family. One HPT-JT tumour with germline mutation also harboured a somatic mutation. In total, seven novel and one previously reported mutation were identified. "Two-hits" (double mutations or one mutation and loss of heterozygosity at 1q24-32) affecting HRPT2 were found in two sporadic carcinomas, two HPT-JT-related and two FIHP related tumours. CONCLUSIONS: The results in this study support the role of HRPT2 as a tumour suppressor gene in sporadic parathyroid carcinoma, and provide further evidence for HRPT2 as the causative gene in HPT-JT, and a subset of FIHP. In light of the strong association between mutations of HRPT2 and sporadic parathyroid carcinoma demonstrated in this study, it is hypothesised that HRPT2 mutation is an early event that may lead to parathyroid malignancy and suggest intragenic mutation of HRPT2 as a marker of malignant potential in both familial and sporadic parathyroid tumours.


Asunto(s)
Neoplasias de las Paratiroides/genética , Proteínas/genética , Adulto , Anciano , Distribución de Chi-Cuadrado , Cromosomas Humanos Par 1/genética , Análisis Mutacional de ADN , ADN Complementario/química , ADN Complementario/genética , ADN de Neoplasias/química , ADN de Neoplasias/genética , Salud de la Familia , Femenino , Humanos , Hiperparatiroidismo/genética , Pérdida de Heterocigocidad , Masculino , Repeticiones de Microsatélite , Persona de Mediana Edad , Mutación , Neoplasias de las Paratiroides/patología , Polimorfismo Genético , Síndrome , Proteínas Supresoras de Tumor
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