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1.
Subcell Biochem ; 79: 345-58, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27485229

RESUMEN

There is an increasing demand for carotenoids, which are fundamental components of the human diet, for example as precursors of vitamin A. Carotenoids are also potent antioxidants and their health benefits are becoming increasingly evident. Protective effects against prostate cancer and age-related macular degeneration have been proposed for lycopene and lutein/zeaxanthin, respectively. Additionally, ß-carotene, astaxanthin and canthaxanthin are high-value carotenoids used by the food industry as feed supplements and colorants. The production and consumption of these carotenoids from natural sources, especially from seeds, constitutes an important step towards fortifying the diet of malnourished people in developing nations. Therefore, attempts to metabolically manipulate ß-carotene production in plants have received global attention, especially after the generation of Golden Rice (Oryza sativa). The endosperms of Golden Rice seeds synthesize and accumulate large quantities of ß-carotene (provitamin A), yielding a characteristic yellow color in the polished grains. Classical breeding efforts have also focused in the development of cultivars with elevated seed carotenoid content, with maize and other cereals leading the way. In this communication we will summarize transgenic efforts and modern breeding strategies to fortify various crop seeds with nutraceutical carotenoids.


Asunto(s)
Carotenoides/metabolismo , Oryza/metabolismo , Semillas/metabolismo , Vitamina A/metabolismo , Biotecnología , Cruzamiento , Carotenoides/biosíntesis , Regulación de la Expresión Génica de las Plantas , Humanos , Oryza/genética , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Semillas/genética , beta Caroteno/biosíntesis , beta Caroteno/metabolismo
2.
J Viral Hepat ; 23(10): 748-54, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27186944

RESUMEN

In the United States, hospitalization among patients with chronic hepatitis C virus (HCV) infection is high. The healthcare burden associated with hospitalization is not clearly known. We analysed data from the Chronic Hepatitis Cohort Study, an observational cohort of patients receiving care at four integrated healthcare systems, collected from 2006 to 2013 to determine all-cause hospitalization rates of patients with chronic HCV infection and the other health system patients. To compare the hospitalization rates, we selected two health system patients for each chronic HCV patient using their propensity score (PS). Propensity score matching was conducted by site, gender, race, age and household income to minimize differences attributable to these characteristics. We also compared primary reason for hospitalization between chronic HCV patients and the other health system patients. Overall, 10 131 patients with chronic HCV infection and 20 262 health system patients were selected from the 1 867 802 health system patients and were matched by PS. All-cause hospitalization rates were 27.4 (27.0-27.8) and 7.4 (7.2-7.5) per 100 persons-year (PY) for chronic HCV patients and for the other health system patients, respectively. Compared to health system patients, hospitalization rates were significantly higher by site, gender, age group, race and household income among chronic HCV patients (P < 0.001). Compared to health system patients, chronic HCV patients were more likely to be hospitalized from liver-related conditions (RR = 24.8, P < 0.001). Hence, patients with chronic HCV infection had approximately 3.7-fold higher all-cause hospitalization rate than other health system patients. These findings highlight the incremental costs and healthcare burden of patients with chronic HCV infection associated with hospitalization.


Asunto(s)
Hepatitis C Crónica/complicaciones , Hospitalización , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Hepatitis C Crónica/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Medición de Riesgo , Estados Unidos/epidemiología , Adulto Joven
3.
Plant Cell Rep ; 24(7): 383-91, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15856235

RESUMEN

Soybean (Glycine max L. Merrill) somatic embryos have been useful for assaying seed-specific traits prior to plant recovery. Such traits could be assessed more accurately if somatic embryos more closely mimicked seed development. Amino acid supplements, carbon source, and abscisic acid and basal salt formulations were tested in an effort to modify existing soybean embryogenesis histodifferentiation/maturation media to further normalize the development of soybean somatic embryos. The resultant liquid medium, referred to as soybean histodifferentiation and maturation medium (SHaM), consists of FNL basal salts, 3% sucrose, 3% sorbitol, filter-sterilized 30 mM glutamine and 1 mM methionine. SHaM-derived somatic embryos are more similar to seed in terms of protein and fatty acid/lipid composition, and conversion ability, than somatic embryos obtained from traditional soybean histodifferentiation and maturation media.


Asunto(s)
Medios de Cultivo/farmacología , Desarrollo Embrionario/fisiología , Glycine max/embriología , Semillas/embriología , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacología , Aminoácidos/metabolismo , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Medios de Cultivo/química , Desarrollo Embrionario/efectos de los fármacos , Glutamina/metabolismo , Glutamina/farmacología , Metionina/metabolismo , Metionina/farmacología , Proteínas de Plantas/metabolismo , Sales (Química)/metabolismo , Sales (Química)/farmacología , Semillas/química , Semillas/efectos de los fármacos , Semillas/metabolismo , Sorbitol/metabolismo , Sorbitol/farmacología , Glycine max/efectos de los fármacos , Glycine max/metabolismo , Sacarosa/metabolismo , Sacarosa/farmacología
4.
Eur J Nucl Med Mol Imaging ; 30(8): 1134-9, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12768332

RESUMEN

Neurotensin (NT) receptors are overexpressed in exocrine pancreatic cancer and Ewing's sarcoma. The potential utility of native NT in cancer diagnosis and therapy is, however, limited by its rapid degradation in vivo. Therefore, NT analogues were synthesised with modified lysine and arginine derivatives to enhance stability and coupled either to DTPA, to enable high specific activity labelling with indium-111 for imaging, or to DOTA, to enable high specific activity labelling with beta-emitting radionuclides, such as lutetium-177 and yttrium-90. Based on serum stability (4 h incubation at 37 degrees C in human serum) and receptor binding affinity, the five most promising analogues were selected and further evaluated in in vitro internalisation studies in human colorectal adenocarcinoma HT29 cells, which overexpress NT receptors. All five NT analogues bound with high affinity to NT receptors on human exocrine pancreatic tumour sections. The analogues could be labelled with (111)In to a high specific activity. The (111)In-labelled compounds were found to be very stable in serum. Incubation of HT29 cells with the (111)In-labelled analogues at 37 degrees C showed rapid receptor-mediated uptake and internalisation. The most promising analogue, peptide 2530 [DTPA-(Pip)Gly-Pro-(PipAm)Gly-Arg-Pro-Tyr-tBuGly-Leu-OH] was further tested in vivo in a biodistribution study using HT29 tumour-bearing nude mice. The results of this study showed low percentages of injected dose per gram tissue of this (111)In-labelled 2530 analogue in receptor-negative organs like blood, spleen, pancreas, liver, muscle and femur. Good uptake was found in the receptor-positive HT29 tumour and high uptake was present in the kidneys. Co-injection of excess unlabelled NT significantly reduced tumour uptake, showing that tumour uptake is a receptor-mediated process. With their enhanced stability, maintained high receptor affinity and rapid receptor-mediated internalisation, the (111)In-labelled DTPA- and DOTA-conjugated NT analogues are excellent candidates for imaging and therapy of exocrine pancreatic cancer, peptide 2530 being the most promising analogue.


Asunto(s)
Compuestos Heterocíclicos con 1 Anillo/farmacocinética , Radioisótopos de Indio/farmacocinética , Neurotensina/análogos & derivados , Neurotensina/farmacocinética , Neoplasias Pancreáticas/metabolismo , Ácido Pentético/farmacocinética , Receptores de Neurotensina/metabolismo , Animales , Evaluación Preclínica de Medicamentos , Estabilidad de Medicamentos , Compuestos Heterocíclicos con 1 Anillo/química , Compuestos Heterocíclicos con 1 Anillo/uso terapéutico , Radioisótopos de Indio/química , Radioisótopos de Indio/uso terapéutico , Marcaje Isotópico/métodos , Tasa de Depuración Metabólica , Ratones , Ratones Desnudos , Neurotensina/uso terapéutico , Especificidad de Órganos , Páncreas/diagnóstico por imagen , Páncreas/metabolismo , Páncreas/efectos de la radiación , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/radioterapia , Ácido Pentético/química , Ácido Pentético/uso terapéutico , Cintigrafía , Radiofármacos/síntesis química , Radiofármacos/farmacocinética , Radiofármacos/uso terapéutico , Distribución Tisular , Recuento Corporal Total
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