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1.
Int J Impot Res ; 24(2): 61-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22072232

RESUMEN

Oxidative stress and inflammation, which disrupt nitric oxide (NO) production directly or by causing resistance to insulin, are central determinants of vascular diseases including ED. Decreased vascular NO has been linked to abdominal obesity, smoking and high intakes of fat and sugar, which all cause oxidative stress. Men with ED have decreased vascular NO and circulating and cellular antioxidants. Oxidative stress and inflammatory markers are increased in men with ED, and all increase with age. Exercise increases vascular NO, and more frequent erections are correlated with decreased ED, both in part due to stimulation of endothelial NO production by shear stress. Exercise and weight loss increase insulin sensitivity and endothelial NO production. Potent antioxidants or high doses of weaker antioxidants increase vascular NO and improve vascular and erectile function. Antioxidants may be particularly important in men with ED who smoke, are obese or have diabetes. Omega-3 fatty acids reduce inflammatory markers, decrease cardiac death and increase endothelial NO production, and are therefore critical for men with ED who are under age 60 years, and/or have diabetes, hypertension or coronary artery disease, who are at increased risk of serious or even fatal cardiac events. Phosphodiesterase inhibitors have recently been shown to improve antioxidant status and NO production and allow more frequent and sustained penile exercise. Some angiotensin II receptor blockers decrease oxidative stress and improve vascular and erectile function and are therefore preferred choices for lowering blood pressure in men with ED. Lifestyle modifications, including physical and penile-specific exercise, weight loss, omega-3 and folic acid supplements, reduced intakes of fat and sugar, and improved antioxidant status through diet and/or supplements should be integrated into any comprehensive approach to maximizing erectile function, resulting in greater overall success and patient satisfaction, as well as improved vascular health and longevity.


Asunto(s)
Disfunción Eréctil/prevención & control , Óxido Nítrico/metabolismo , Envejecimiento/metabolismo , Consumo de Bebidas Alcohólicas , Antagonistas de Receptores de Angiotensina/uso terapéutico , Antioxidantes/uso terapéutico , Dieta Baja en Carbohidratos , Dieta con Restricción de Grasas , Disfunción Eréctil/dietoterapia , Disfunción Eréctil/metabolismo , Ejercicio Físico , Ácidos Grasos Omega-3/metabolismo , Humanos , Estilo de Vida , Masculino , Estrés Oxidativo , Inhibidores de Fosfodiesterasa 5/uso terapéutico , Insuficiencia Renal/metabolismo , Cese del Hábito de Fumar , Testosterona/uso terapéutico , Enfermedades Vasculares/dietoterapia , Enfermedades Vasculares/metabolismo , Enfermedades Vasculares/prevención & control , Pérdida de Peso
2.
Environ Pollut ; 157(10): 2830-6, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19427085

RESUMEN

Aluminium-based water treatment residual (Al-WTR) is the most widely generated residual from water treatment facilities worldwide. It is regarded as a by-product of no reuse potential and landfilled. This study assessed Al-WTR as potential phosphate-removing substrate in engineered wetlands. Results indicate specific surface area ranged from 28.0 m(2) g(-1) to 41.4 m(2) g(-1). X-ray Diffraction, Fourier transform infrared and energy-dispersive X-ray spectroscopes all indicate Al-WTR is mainly composed of amorphous aluminium which influences its phosphorus (P) adsorption capacity. The pH and electrical conductivity ranged from 5.9 to 6.0 and 0.104 dS m(-1) to 0.140 dS m(-1) respectively, showing that it should support plant growth. Batch tests showed adsorption maxima of 31.9 mg P g(-1) and significant P removal was achieved in column tests. Overall, results showed that Al-WTR can be used for P removal in engineered wetlands and it carries the benefits of reuse of a by-product that promotes sustainability.


Asunto(s)
Aluminio/química , Fósforo/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Adsorción , Purificación del Agua/instrumentación , Abastecimiento de Agua/análisis , Humedales
3.
J Biomed Mater Res B Appl Biomater ; 80(1): 201-10, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16850478

RESUMEN

Novel FeAlCr oxide dispersion strengthened intermetallics that are processed by powder metallurgy have been developed as potential biomaterials. The alloys exhibit a small grain size and a fine dispersion of yttria provides the material with a high yield strength and depending on the alloy composition good ductility (up to 5%). The biocompatibility of the alloy was assessed in comparison with commercial alumina. Saos-2 osteoblast-like cells were either challenged with mechanically alloyed particles, or seeded onto solid samples. Viability and proliferation of cells were substantially unaffected by the presence of a high concentration of particles (1 mg/mL). Solid samples of novel FeAlCr intermetallic have shown a good biocompatibility in vitro, often approaching the behavior of materials well known for their biological acceptance (e.g. alumina). It has been found that osteoblasts are able to produce ALP, a specific marker of cells with bone-forming activity. In this respect, ALUSI alloys hold the promise to be suitable substrate for bone integration. The finding of no cytotoxic effect in the presence of the alloy particles is a reliable proof of the absence of acute toxicity of the material.


Asunto(s)
Aleaciones , Sustitutos de Huesos , Ensayo de Materiales , Nanopartículas , Osteoblastos/citología , Fosfatasa Alcalina/análisis , Aleaciones/química , Aluminio/química , Óxido de Aluminio/química , Antígenos de Diferenciación/análisis , Línea Celular , Proliferación Celular , Supervivencia Celular , Humanos , Hierro/química , Nanopartículas/química , Nanopartículas/ultraestructura , Osteoblastos/enzimología , Titanio/química
4.
J Neuroendocrinol ; 13(4): 347-52, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11264722

RESUMEN

The cocaine-amphetamine regulated transcript (CART) encodes for a protein which has an important role in the regulation of appetite and body weight. To date, no details of the molecular events and signal transduction pathways which regulate this gene are available. We report the identification of CART gene expression in the GH3 pituitary cell line. We have used activators of the cAMP or protein kinase C (PKC) signal transduction pathways to show that, in GH3 cells, CART is transcriptionally up-regulated by activators of the cAMP signal transduction pathway. We also identify CART gene expression in ovine pars tuberalis (PT) tissue and primary cell cultures. In PT cells in contrast to GH3 cells, CART gene expression is upregulated by activators of the PKC signal transduction pathway. Cultured cells have provided a valuable resource for the detailed analysis of specific regulatory mechanisms underlying transcriptional or translational regulation of genes, signal transduction events and many other cellular processes. GH3 and PT cells may therefore provide a resource for the further detailed molecular analysis of the events regulating CART gene expression and processing.


Asunto(s)
Regulación de la Expresión Génica/fisiología , Proteínas del Tejido Nervioso/metabolismo , Hipófisis/metabolismo , Animales , Bucladesina/farmacología , Células Cultivadas , Colforsina/análogos & derivados , Colforsina/farmacología , AMP Cíclico/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Hipotálamo/citología , Hipotálamo/efectos de los fármacos , Hipotálamo/metabolismo , Hibridación in Situ , Eminencia Media/citología , Eminencia Media/efectos de los fármacos , Eminencia Media/metabolismo , Proteínas del Tejido Nervioso/genética , Neuropéptidos/farmacología , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa , Hipófisis/citología , Hipófisis/efectos de los fármacos , Adenohipófisis/citología , Adenohipófisis/efectos de los fármacos , Adenohipófisis/metabolismo , Proteína Quinasa C/metabolismo , ARN Mensajero/metabolismo , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sistemas de Mensajero Secundario/efectos de los fármacos , Ovinos , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Acetato de Tetradecanoilforbol/farmacología , Hormona Liberadora de Tirotropina/farmacología
5.
Hum Genet ; 105(5): 399-409, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10598804

RESUMEN

To contribute to the creation of a transcription map of human chromosome 21 (HC21) and to the identification of genes that may be involved in the pathogenesis of Down syndrome, exon trapping was performed from HC21-specific cosmids covering the entire chromosome. More than 700 exons have been identified to date. One such exon, hmc01a06, maps to YAC 831B6 which contains marker D21Z1 (alphoid repeats) and had previously been localized to the pericentromeric region of HC21. Northern-blot analysis revealed a 2.5-kb mRNA species strongly and exclusively expressed in the testis. We cloned the corresponding full-length cDNA, which encodes a predicted polypeptide of 551 amino acids with at least two potential transmembrane domains and a tyrosine phosphatase motif. The cDNA has sequence homology to chicken tensin, bovine auxilin and rat cyclin-G associated kinase (GAK). The entire polypeptide sequence also has significant homology to tumor suppressor PTEN/MMAC1 protein. We termed this novel gene/protein TPTE (transmembrane phosphatase with tensin homology). Polymerase chain reaction amplification, fluorescent in situ hybridization, Southern-blot and sequence analysis using monochromosomal somatic cell hybrids showed that this gene has highly homologous copies on HC13, 15, 22, and Y, in addition to its HC21 copy or copies. The estimated minimum number of copies of the TPTE gene in the haploid human genome is 7 in male and 6 in female. Zoo-blot analysis showed that TPTE is conserved between humans and other species. The biological function of the TPTE gene is presently unknown; however, its expression pattern, sequence homologies, and the presence of a potential tyrosine phosphatase domain suggest that it may be involved in signal transduction pathways of the endocrine or spermatogenetic function of the testis. It is also unknown whether all copies of TPTE are functional or whether some are pseudogenes. TPTE is, to our knowledge, the gene located closest to the human centromeric sequences.


Asunto(s)
Cromosomas Humanos Par 13/genética , Cromosomas Humanos Par 15/genética , Cromosomas Humanos Par 21/genética , Cromosomas Humanos Par 22/genética , Proteínas de la Membrana/genética , Proteínas Tirosina Fosfatasas/genética , Testículo/enzimología , Cromosoma Y/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bovinos , Mapeo Cromosómico , Secuencia Conservada , ADN Complementario/genética , Exones , Femenino , Humanos , Hibridación Fluorescente in Situ , Masculino , Proteínas de Microfilamentos/genética , Datos de Secuencia Molecular , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie , Tensinas , Distribución Tisular
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