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1.
Plant Foods Hum Nutr ; 73(3): 180-188, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30062579

RESUMEN

Six native plants of South America traditionally consumed in the Patagonian region (southern Argentina and Chile), namely: Adesmia boronioides Hook. f., Apium australe Thouars, Buddleja globosa Hope, Drimys andina (Reiche) R. Rodr. & Quezada, Dysphania multifida L. and Solidago chilensis Meyen were investigated to determine the nutraceutical properties of infusions of their aerial parts. The infusions were characterized in terms of their antioxidant activity, phenolic and flavonoid content, profile of phenolic compounds, general toxicity and cytotoxicity on two different human cell lines: T84 (derived from colon cancer) and HTR8/SVneo (not derived from cancer). Twenty-nine compounds, mainly phenolic acids and flavonoids, were identified. This is the first analysis of phenolic compounds in infusions from native plants of Patagonia. D. andina, B. globosa and S. chilensis showed high levels of antioxidants, even higher than those of Green Tea. The content of phenolic compounds correlated significantly with the antioxidant activity of the samples analyzed. The toxicity test indicated that the use of A. australe, B. globosa and D. multifida seems safe, but a moderate consumption is suggested for A. boronioides, D. andina and S. chilensis until more exhaustive and long-term results are available. Moreover, A. boronioides and S. chilensis showed anticancer potential due to their antiproliferative activity on human cancer cell lines.


Asunto(s)
Antioxidantes/farmacología , Suplementos Dietéticos/análisis , Flavonoides/análisis , Fenoles/análisis , Preparaciones de Plantas/farmacología , Plantas/química , Antioxidantes/análisis , Argentina , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Chile , Humanos , Hidroxibenzoatos/análisis , Componentes Aéreos de las Plantas/química , Preparaciones de Plantas/análisis
2.
Neuroimage ; 146: 770-777, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-27989840

RESUMEN

In the present study we applied online transcranial magnetic stimulation (TMS) bursts at 10Hz to the supplementary motor area (SMA) and primary motor cortex to test whether these regions are causally involved in mental rotation. Furthermore, in order to investigate what is the specific role played by SMA and primary motor cortex, two mental rotation tasks were used, which included pictures of hands and abstract objects, respectively. While primary motor cortex stimulation did not affect mental rotation performance, SMA stimulation improved the performance in the task with object stimuli, and only for the pairs of stimuli that had higher angular disparity between each other (i.e., 100° and 150°). The finding that the effect of SMA stimulation was modulated by the amount of spatial orientation information indicates that SMA is causally involved in the very act of mental rotation. More specifically, we propose that SMA mediates domain-general sequence processes, likely required to accumulate and integrate information that are, in this context, spatial. The possible physiological mechanisms underlying the facilitation of performance due to SMA stimulation are discussed.


Asunto(s)
Imaginación/fisiología , Corteza Motora/fisiología , Percepción Espacial/fisiología , Percepción Visual/fisiología , Adulto , Potenciales Evocados Motores , Femenino , Humanos , Masculino , Estimulación Luminosa , Tiempo de Reacción , Rotación , Estimulación Magnética Transcraneal , Adulto Joven
3.
Nature ; 522(7555): 197-201, 2015 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-26062511

RESUMEN

Our current understanding of ocean-atmosphere-cryosphere interactions at ice-age terminations relies largely on assessments of the most recent (last) glacial-interglacial transition, Termination I (T-I). But the extent to which T-I is representative of previous terminations remains unclear. Testing the consistency of termination processes requires comparison of time series of critical climate parameters with detailed absolute and relative age control. However, such age control has been lacking for even the penultimate glacial termination (T-II), which culminated in a sea-level highstand during the last interglacial period that was several metres above present. Here we show that Heinrich Stadial 11 (HS11), a prominent North Atlantic cold episode, occurred between 135 ± 1 and 130 ± 2 thousand years ago and was linked with rapid sea-level rise during T-II. Our conclusions are based on new and existing data for T-II and the last interglacial that we collate onto a single, radiometrically constrained chronology. The HS11 cold episode punctuated T-II and coincided directly with a major deglacial meltwater pulse, which predominantly entered the North Atlantic Ocean and accounted for about 70 per cent of the glacial-interglacial sea-level rise. We conclude that, possibly in response to stronger insolation and CO2 forcing earlier in T-II, the relationship between climate and ice-volume changes differed fundamentally from that of T-I. In T-I, the major sea-level rise clearly post-dates Heinrich Stadial 1. We also find that HS11 coincided with sustained Antarctic warming, probably through a bipolar seesaw temperature response, and propose that this heat gain at high southern latitudes promoted Antarctic ice-sheet melting that fuelled the last interglacial sea-level peak.


Asunto(s)
Cubierta de Hielo , Agua de Mar/análisis , Regiones Antárticas , Organismos Acuáticos/metabolismo , Océano Atlántico , Clima , Foraminíferos/metabolismo , Historia Antigua , Región Mediterránea , Mar Mediterráneo , Plancton/metabolismo , Temperatura
4.
Fish Shellfish Immunol ; 18(4): 311-25, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15561561

RESUMEN

The present study investigated the immunomodulatory activity of Ergosan, an algal extract containing alginic acid, and Macrogard, a yeast extract containing beta-glucans, on innate and specific immunity in sea bass (Dicentrarchus labrax). Four cycles of experimental feeding using normal fish feed formulation (control group) supplemented with Ergosan (0.5%) or Macrogard (0.1%) were performed at 60-day intervals (15 days of treatment+45 days of suspension). Serum complement, lysozyme, total proteins and heat shock protein (HSP) concentrations were measured at 15, 30 and 45 days from the end of the first 15-day feeding cycle (short term) and 45 days after the end of each feeding cycle over a 35-week period (long term). The percentage of B- and T-lymphocytes in peripheral blood leucocytes and gut were measured over long-term trial. Significant elevation (P < 0.05) in serum complement activity occurred in sea bass fed with alginic acid and glucans, at 15 days from the end of first cycle of treatment. Significant elevation (P < 0.05) in serum lysozyme, gill and liver HSP concentration were observed in the same experimental groups at 30 days from the end of treatment, whereas a significant increase (P < 0.05) of complement activity was only observed in fish that received an Ergosan diet. At 45 days from the end of treatment, complement, lysozyme and HSP concentration did not differ among groups. Over the long-term period, no significant differences were observed in innate and specific immune parameters, survival, growth performances and conversion index in treated and control fish. A dramatic decrease of both innate and acquired immune parameters was observed during the winter season in all groups, followed by a partial recovery when water temperature increased. Reduction in complement and lysozyme activities was significatively correlated (p < 0.01) to water temperature variation. The results suggested the potential of alginic acid and beta-glucans to activate some innate immune responses in sea bass, and particularly under conditions of immunodepression related to environmental stress.


Asunto(s)
Alginatos/farmacología , Lubina/inmunología , Ácido Glucurónico/farmacología , Ácidos Hexurónicos/farmacología , Inmunidad Innata/efectos de los fármacos , beta-Glucanos/farmacología , Alginatos/administración & dosificación , Alimentación Animal/análisis , Animales , Anticuerpos Monoclonales , Lubina/crecimiento & desarrollo , Western Blotting , Pesos y Medidas Corporales , Ensayo de Actividad Hemolítica de Complemento , Eucariontes , Citometría de Flujo , Técnica del Anticuerpo Fluorescente Indirecta , Ácido Glucurónico/administración & dosificación , Proteínas de Choque Térmico/metabolismo , Ácidos Hexurónicos/administración & dosificación , Italia , Linfocitos , Muramidasa/metabolismo , Factores de Tiempo , Levaduras , beta-Glucanos/administración & dosificación
5.
J Physiol Biochem ; 60(1): 31-7, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15352382

RESUMEN

We investigated whether dietary supplementation with L-arginine, the endogenous precursor of nitric oxide, might affect serum lipid levels and activities of intestinal mucosa enzymes in animals, in which diabetes was induced by administration of streptozotocin. Control and diabetic rats were fed diets with or without 2% L-arginine supplementation for 4 weeks. Diabetic rats had significantly higher concentrations of serum triglycerides and LDL-cholesterol than control rats. These alterations were partially reduced by L-arginine supplementation. Experimental diabetes did not influence the lactase and leucine aminopeptidase activity in the intestine, but the activity of alkaline phosphatase was increased. Furthermore, activities of maltase and sucrase in the intestinal mucosa were elevated in streptozotocin-induced diabetic rats and were restored to control levels after dietary L-arginine supplementation. On the basis of the present experimental evidence, dietary L-arginine supplementation appears to affect the metabolism of lipoproteins and might alleviate some gastrointestinal dysfunctions, commonly seen in diabetes mellitus.


Asunto(s)
Arginina/administración & dosificación , Colesterol/sangre , Diabetes Mellitus Experimental/sangre , Suplementos Dietéticos , Intestinos/enzimología , Triglicéridos/sangre , Animales , Glucemia/análisis , Diabetes Mellitus Experimental/enzimología , Masculino , Ratas , Ratas Sprague-Dawley
6.
PDA J Pharm Sci Technol ; 54(3): 172-92, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10927910

RESUMEN

The enumeration of microorganisms in water for pharmaceutical purposes using the MicroCount Digital System (Millipore Corporation, Bedford, MA) was compared to the USP-recommended Pour Plate and Membrane Filtration Count methods. A study, using a pure culture of Buckholderia cepacia, ATCC#25416, showed that the accuracy, precision, reproducibility and linearity of the MicroCount ATP Bioluminescence System was equivalent to or better than the traditional methods. When the MicroCount System was used to monitor purified water and water for injection taps in a pharmaceutical plant over a month, comparable counts to the traditional methods were obtained within 24 hours compared to 48 to 72 hours with the other methods. The effectiveness of the memory device used for the isolation of colonies for characterization was demonstrated by comparing the number and pattern of the positive wells in the MicroCount plates with the isolation of colonies on the microbial count agar plates. The recovery on agar plates, although slightly higher, was not statistically different to the MicroCount plates. The predominated microorganisms isolated using all three methods were Ralstonia pickettii, Bacillus sphaericus, Stenotrophomonas maltophia, and a Staphylococcus species.


Asunto(s)
Recuento de Colonia Microbiana/métodos , Microbiología del Agua , Filtración , Sensibilidad y Especificidad
7.
J Vet Med B Infect Dis Vet Public Health ; 47(10): 745-51, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11204129

RESUMEN

Immunostimulants represent a modern and promising tool in aquaculture, enhancing the resistance of cultured fish to disease and stress. This study investigated the effect of a combination of dietary glucans, alpha-tocopherol and ascorbic acid on the innate immune response of cultured sea bass (Dicentrarchus labrax). After 5 weeks of adaptation on a commercial diet containing 100 p.p.m. ascorbic acid and 200 p.p.m. alpha-tocopherol, sea bass were switched to a diet supplemented with 2% beta-1.3/beta-1.6 glucans and ascorbic acid and alpha-tocopherol at 500 p.p.m. The supplemented diet was given at 2% of body weight per day over a 2-week period, every 3 months. Plasma lysozyme concentration, content and distribution of major plasma proteins and complement activity were measured prior to feeding the supplemented diet and after 40 weeks. Alternative pathways of complement activation and lysozyme activity were both significantly enhanced in fish fed on glucans and elevated doses of vitamins. No significant differences were observed in protein content or in albumin/globulin ratio. Compared to lysozyme activity, which showed marked individual variation, complement-mediated haemolytic activity has been shown to be a more reliable indicator of sea bass immunocompetence. Further studies are in progress to clarify the effect of each dietary component on the innate immune response and disease resistance.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Lubina/inmunología , Dieta/veterinaria , Administración Oral , Animales , Ácido Ascórbico/administración & dosificación , Proteínas del Sistema Complemento/metabolismo , Suplementos Dietéticos , Glucanos/administración & dosificación , Muramidasa/sangre , Vitamina E/administración & dosificación
9.
Allergol Immunopathol (Madr) ; 17(6): 307-11, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2635832

RESUMEN

The capacity of certain foods to cause allergic reactions is well known. The four types of mechanisms that Gell and Coombs described in 1968, are involved in these reactions, although the reaginic antibodies retain the paramount attention of the immunologists. The physiochemical composition of the allergen molecule is the goal of investigators with the purpose to clarify the intrinsic kinetics of antibody synthesis. This paper contributes to the conflicting data about orange allergens especially those obtained from Citrus Aurantium Sinensis and Citrus Silension (CAS and CS, respectively). Glycoproteins were separated by gel filtration through a Sephadex G-50 column. A definite protein peak was obtained meanwhile several hexoses appeared throughout the fractionation procedure. These molecules have adequate physiochemical properties that make them able to trigger the immunological response (molecular weight, definite chemical composition and glycoprotein content). Although CAS and CS have a similar chemical composition a slight inverse proportion of proteins and hexoses was demonstrated between the two classes. Molecular weights were different for CAS (51.500) and for CS (37.000) in comparison with well established protein makers. Ouchterlony revealed two precipitin lines in the CAS-anti-CAS system but none in the CS-anti-CS one. The Boyden technique showed a titre of 1/256 in the first case and only of 1/64 in the second of specific anti-orange antibodies. All the eluted fractions gave negative results although they were concentrated ten times by pre-evaporation. This animal model reinforced the statement that after a long and continuous exposure to orange antigens it was possible to develop specific antibodies. It is assumed that this phenomenon happens in atopic children with it's diagnostic and therapeutic importance.


Asunto(s)
Alérgenos/inmunología , Citrus/inmunología , Glicoproteínas/inmunología , Proteínas de Plantas/inmunología , Alérgenos/aislamiento & purificación , Animales , Formación de Anticuerpos , Especificidad de Anticuerpos , Cromatografía en Gel , Citrus/análisis , Glicoproteínas/aislamiento & purificación , Inmunización , Inmunoglobulina G/biosíntesis , Inmunoglobulina G/inmunología , Extractos Vegetales/inmunología , Proteínas de Plantas/aislamiento & purificación , Conejos
10.
Biochem J ; 99(3): 595-8, 1966 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6007357

RESUMEN

1. The amino acid composition of highly purified aspartate aminotransferase from ox heart was determined. 2. Alanine is the only N-terminal residue. 3. Leucine was identified as the only C-terminal residue. 4. No disulphide bridges are present in the enzyme molecule. 5. The thiol groups are not equally accessible, the accessibility being comparatively easier in the apoenzyme molecule.


Asunto(s)
Aspartato Aminotransferasas/análisis , Miocardio/enzimología , Aminoácidos/análisis , Animales , Autoanálisis , Bovinos , Cisteína/análisis , Nitrógeno/análisis , Fósforo/análisis , Fosfato de Piridoxal/análisis , Triptófano/análisis
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