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1.
Res Sports Med ; 30(3): 295-307, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33579162

RESUMEN

The evolution of functional classification (FT) is important for promoting competitive balance. Technological advances allow the objective monitoring of competitive demands that is required to manage and individualize workloads. Therefore, this study aimed to characterize external workload in all matches from the 2018/2019 season of the CPF7 Spanish National League and to compare demands based on the new FT (FT1, FT2 yFT3) in time-motion (locomotion and speed changes) and accelerometer-based workload (impacts). Statistical analysis was composed of one-way ANOVA with Bonferroni post-hoc and omega partial squared effect size. Differences were found among all FT in total distance, running, high-intensity, sprinting, very high accelerations and decelerations (FT3> FT2> FT1; p < .01; ωp2= 0.29-to-0.43); and with respect to the highest functional limitation (FT3 = FT2> FT1) in maximum sprinting, moderate-high accelerations and decelerations, total impacts and at very-low intensity (ωp2= 0.13-to-0.29). In conclusion, FT3 players presented a physical advantage with respect to FT2-FT1 players in competition, especially in high-intensity actions that are crucial in team-sports performance. The present results facilitate designing specific training workloads according to FT, players' disability and competition demands, being the first approach to characterize match demands with inertial devices based on the new FT.


Asunto(s)
Rendimiento Atlético , Parálisis Cerebral , Fútbol Americano , Fútbol , Humanos , Estaciones del Año , Carga de Trabajo
2.
Eur J Vasc Endovasc Surg ; 51(4): 543-9, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26810343

RESUMEN

OBJECTIVES: Pre-operative anemia has been associated with increased post-operative morbidity and mortality in elective cardiac surgery, but its association with post-operative mortality after open or endovascular surgery for critical limb ischemia (CLI) is not well established. The aim of this study was to evaluate the relationship between pre-operative anemia and mortality in surgery for CLI. MATERIALS AND METHODS: A retrospective study of 403 consecutive patients (mean age = 73; 73% male) undergoing open (n = 191, 47%) or endovascular (n = 212, 53%) surgery for CLI between 2005 and 2013 was performed. Neither redo revascularization procedures (ipsilateral or contralateral) nor acute limb ischemia patients were included as new cases. RESULTS: The best cut off (receiver operating characteristic curve) that related pre-operative hemoglobin to mortality was 10 g/dL. The immediate (in hospital or < 30 days) mortality rate was 8% (32 patients), with no significant differences between open and endovascular surgery. Patients with a pre-operative hemoglobin <10 g/dl had a higher immediate mortality rate (17.7% vs. 5.1%), with a risk (OR), adjusted by age and prior myocardial infarction, of 3.9, 95% CI 1.8-8.4 (p = 0.001). The mean follow up of the cohort was 30 months (97% complete). Similarly, a pre-operative hemoglobin <10 g/dL was significantly associated with a lower 1 year (55 vs. 83%) and 5 year survival rate (21 vs. 53%) with an associated risk (HR) of 2.5, 95% CI 1.8-3.4 (p < 0.001) adjusted by age, previous myocardial infarction, chronic renal failure, stroke, diabetes mellitus, and ischemic ulcers. CONCLUSIONS: Pre-operative anemia is a risk factor for immediate and late mortality among patients with CLI, regardless of other risk factors and the type of revascularization technique. Prospective studies are needed to evaluate the potential effect of its treatment on survival outcomes.


Asunto(s)
Anemia/mortalidad , Procedimientos Endovasculares/mortalidad , Isquemia/terapia , Enfermedad Arterial Periférica/terapia , Procedimientos Quirúrgicos Vasculares/mortalidad , Anciano , Anciano de 80 o más Años , Anemia/sangre , Anemia/complicaciones , Anemia/diagnóstico , Área Bajo la Curva , Biomarcadores/sangre , Distribución de Chi-Cuadrado , Enfermedad Crítica , Procedimientos Endovasculares/efectos adversos , Femenino , Hemoglobinas/metabolismo , Humanos , Isquemia/complicaciones , Isquemia/diagnóstico , Isquemia/mortalidad , Isquemia/cirugía , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Enfermedad Arterial Periférica/complicaciones , Enfermedad Arterial Periférica/diagnóstico , Enfermedad Arterial Periférica/mortalidad , Enfermedad Arterial Periférica/cirugía , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Curva ROC , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/efectos adversos
3.
Plant Biol (Stuttg) ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38985650

RESUMEN

The recent biological invasion of box tree moth Cydalima perspectalis on Buxus trees has a major impact on European boxwood stands through severe defoliation. This can hinder further regrowth and threaten survival of populations. In a mesocosm approach and controlled larval density over a 2-month period, responses of B. sempervirens essential and specialized metabolites were characterized using metabolomics, combining 1H-NMR and LC-MS/MS approaches. This is the first metabolome depiction of major Buxus responses to boxwood moth invasion. Under severe predation, remaining green leaves accumulate free amino acids (with the noticeable exception of proline). The leaf trans-4-hydroxystachydrine and stachydrine reached 10-13% and 2-3% (DW), while root content was lower but also modulated by predation level. Larval predation promoted triterpenoid and (steroidal) alkaloid synthesis and diversification, while flavonoids did not seem to have a relevant role in Buxus resistance. Our results reveal the concomitant responses of central and specialized metabolism, in relation to severity of predation. They also confirm the potential of metabolic profiling using 1H-NMR and LC-MS to detect re-orchestration of metabolism of native boxwood after severe herbivorous predation by the invasive box-tree moth, and thus their relevance for plant-insect relationships and ecometabolomics.

4.
Sci Total Environ ; 946: 174403, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-38960198

RESUMEN

Conventional plastics have become a major environmental concern due to their persistence and accumulation in marine ecosystems. The development of potential degradable polymers (PBP), such as polyhydroxyalkanoates (PHAs) and polylactic acid (PLA), has gained attention as an alternative to mitigate plastic pollution, since they have the potential to biodegrade under certain conditions, and their production is increasing as replacement of conventional polyolefins. This study aimed to assess and compare the toxicity of leachates of pre-compounding PBP (PLA and the PHA, polyhydroxybutyrate-covalerate (PHBv)) and polypropylene (PP) on five marine planktonic species. A battery of standard bioassays using bacteria, microalgae, sea urchin embryos, mussel embryos and copepod nauplii was conducted to assess the toxicity of leachates from those polymers. Additionally, the presence of chemical additives in the leachates was also verified through GC-MS and LC-HRMS analysis. Results showed that PHBv leachates exhibited higher toxicity compared to other polymers, with the microalgae Rhodomonas salina, being the most sensitive species to the tested leachates. On the other hand, PP and PLA generally displayed minimal to no toxicity in the studied species. Estimated species sensitivity distribution curves (SSD) show that PHBv leachates can be 10 times more hazardous to marine plankton than PP or PLA leachates, as demonstrated by the calculated Hazardous Concentration for 5 % of species (HC5). Qualitative chemical analysis supports the toxicological results, with 80 % of compounds being identified in PHBv leachates of which 2,4,6-trichlorophenol is worth mentioning due to the deleterious effects to aquatic biota described in literature. These findings underscore the fact that whereas environmental persistence can be targeted using PBP, the issue of chemical safety remains unsolved by some alternatives, such as PHBv. Gaining a comprehensive understanding of the toxicity profiles of PBP materials through a priori toxicological risk assessment is vital for their responsible application as alternatives to conventional plastics.


Asunto(s)
Plancton , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/toxicidad , Plancton/efectos de los fármacos , Animales , Polímeros/toxicidad , Poliésteres/toxicidad , Pruebas de Toxicidad Aguda , Organismos Acuáticos/efectos de los fármacos , Biodegradación Ambiental
5.
Phys Rev Lett ; 109(10): 100403, 2012 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-23005267

RESUMEN

A Schrödinger equation may be unitarily transformed into dynamical equations in different interaction pictures which describe a common physical process, i.e., the same underlying interactions and dynamics. In contrast to this standard scenario, other relations are also possible, such as a common interaction-picture dynamical equation corresponding to several Schrödinger equations that represent different physical processes. This may enable us to design alternative and feasible experimental routes for operations that are a priori difficult or impossible to perform. The power of this concept is exemplified by engineering Hamiltonians that improve the performance or make realizable several shortcuts to adiabaticity.

6.
Artículo en Inglés | MEDLINE | ID: mdl-34340958

RESUMEN

In recent months, much of the scientific efforts have focused on research on SARSCoV-2 infection and its consequences in humans. Still, many aspects remain unknown. It is known that the damage caused by SARS-CoV-2 is multifactorial and that its extension goes beyond lung inflammation and the acute phase, with the appearance of numerous complications and sequelae. To date, knowledge about the usefulness of 18F-FDG-PET/CT in the acute phase has been limited to the incidental detection of SARS-CoV-2 unsuspected pneumonia. Recent studies have been appearing collecting the findings of 18F-FDG-PET/CT in long COVID-19 or persistent COVID-19 state as well as the alterations caused after mass vaccination of the population in the metabolic studies. This work aims to review the existing literature focusing on these three issues and to briefly present our own preliminary experience.


Asunto(s)
COVID-19/complicaciones , COVID-19/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiofármacos , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos
7.
Rev Esp Med Nucl Imagen Mol ; 40(5): 299-309, 2021.
Artículo en Español | MEDLINE | ID: mdl-35368611

RESUMEN

In recent months, much of the scientific efforts have focused on research on SARSCoV-2 infection and its consequences in humans. Still, many aspects remain unknown. It is known that the damage caused by SARS-CoV-2 is multifactorial and that its extension goes beyond lung inflammation and the acute phase, with the appearance of numerous complications and sequelae. To date, knowledge about the usefulness of 18F-FDG-PET/CT in the acute phase has been limited to the incidental detection of SARS-CoV-2 unsuspected pneumonia. Recent studies have been appearing collecting the findings of 18F-FDG- PET/CT in long COVID-19 or persistent COVID-19 state as well as the alterations caused after mass vaccination of the population in the metabolic studies. This work aims to review the existing literature focusing on these three issues and to briefly present our own preliminary experience.


Asunto(s)
COVID-19 , COVID-19/complicaciones , COVID-19/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiofármacos , SARS-CoV-2 , Síndrome Post Agudo de COVID-19
8.
J Evol Biol ; 22(6): 1183-92, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19416414

RESUMEN

Specialization of some plants on seed-eating pollinators is intriguing, especially when co-pollinators exclusively feeding on nectar are also present. We examined the stability of the morphological specialization of Trollius europaeus (L.) globeflowers with respect to Chiastocheta (Pokorny) flies by artificially opening the flowers. In the montane and subalpine environments studied, other visitors contributed 2% and 28% of all the visits, respectively, and visited open flowers nearly eight times more often than closed flowers, but in both environments their contribution to pollination did not compensate for Chiastocheta aversion against open phenotypes. Net seed set (female success) was slightly higher (+4%) and pollen export (male success) was much higher (+85%) for closed than open flowers. Selection in favour of the closed phenotype was even more intense in patches where open phenotypes were most common, precluding the evolution of open flowers in the study populations.


Asunto(s)
Dípteros , Ecosistema , Flores/anatomía & histología , Polinización , Ranunculaceae/anatomía & histología , Animales , Evolución Biológica , Colorantes Fluorescentes , Francia , Oviposición , Fenotipo , Semillas/crecimiento & desarrollo
9.
J Hazard Mater ; 360: 452-460, 2018 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-30142596

RESUMEN

Toxicity of polyethylene microplastics (PE-MP) of size ranges similar to their natural food to zooplanktonic organisms representative of the main taxa present in marine plankton, including rotifers, copepods, bivalves, echinoderms and fish, was evaluated. Early life stages (ELS) were prioritized as testing models in order to maximize sensitivity. Treatments included particles spiked with benzophenone-3 (BP-3), a hydrophobic organic chemical used in cosmetics with direct input in coastal areas. Despite documented ingestion of both virgin and BP-3 spiked microplastics no acute toxicity was found at loads orders of magnitude above environmentally relevant concentrations on any of the invertebrate models. In fish tests some effects, including premature or reduced hatching, were observed after 12 d exposure at 10 mg L-1 of BP-3 spiked PE-MP. The results obtained do not support environmentally relevant risk of microplastics on marine zooplankton. Similar approaches testing more hydrophobic chemicals with higher acute toxicity are needed before these conclusions could be extended to other organic pollutants common in marine ecosystems. Therefore, the replacement of these polymers in consumer products must be carefully considered.


Asunto(s)
Polietileno/toxicidad , Contaminantes Químicos del Agua/toxicidad , Zooplancton/efectos de los fármacos , Animales , Invertebrados/efectos de los fármacos , Tamaño de la Partícula , Pruebas de Toxicidad Aguda
10.
Chem Commun (Camb) ; 53(26): 3733-3736, 2017 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-28300249

RESUMEN

A new D3h-symmetry tris-N-heterocyclic carbene ligand has been prepared and coordinated to iridium and gold. The ligand contains an electron-poor hexaazatriphenylene core; thus, the resulting tris-NHC ligand is a poor electron donor. The tris-Au(i) complex was tested in the hydroamination of terminal alkynes and in the three-component Strecker reaction.

11.
Dalton Trans ; 45(36): 14154-9, 2016 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-27530887

RESUMEN

Three different Ir(iii) complexes with pyrene-containing N-heterocyclic carbenes have been prepared and characterized. Two complexes contain a monodentate pyrene-imidazolylidene ligand, and have the formulae [IrCp*Cl2(pyrene-NHC)] and [IrCp*(CO3)(pyrene-NHC)]. The third complex is a dimetallic complex with a pyrene-di-imidazolylidene bridging ligand, with the formula [{IrCp*(CO3)}2(µ-pyrene-di-NHC)]. The catalytic activity of the three complexes was tested in the H/D exchange of organic substrates, and in the ß-alkylation of 1-phenylethanol with primary alcohols. In the deuteration of organic substrates, the carbonate complexes are active even in the absence of additives. The dimetallic complex is the most active one in the catalytic coupling of alcohols, a result that may be interpreted as a consequence of the cooperativity between the two metal centres.

12.
Mar Pollut Bull ; 50(12): 1649-60, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16095626

RESUMEN

The 1998 project ECOPORT, "Towards A Sustainable Transport Network", developed by the Valencia Port Authority (VPA), established the bases for implementing an Environmental Management System (EMS) in industrial harbours. The use of data and information shall always be required to develop an efficient EMS. The objective of the present research (INDAPORT) study is to propose a system of sustainable environmental management indicators to be used by any port authorities. All activities performed within a port area are analysed for any potential environmental impacts and risks. An environmental analysis of port activities has been carried out with the objective of designing the indicators system. Twenty-one corresponding activities have been identified for large industrial ports. Subsequently, the same methodology developed to date will be later applied to other Spanish and European ports. The study has been developed by using an original system and a methodology, which simultaneously use stage diagrams and systemic models (material and energy flow charts). Multi-criteria analysis techniques were used to evaluate potential impacts (identification of factors and evaluation of impacts).


Asunto(s)
Técnicas de Apoyo para la Decisión , Monitoreo del Ambiente , Modelos Teóricos , Gestión de Riesgos/métodos , Navíos , Ambiente , Aceites Combustibles , Formulación de Políticas , Medición de Riesgo , España
13.
Artículo en Inglés | MEDLINE | ID: mdl-25679712

RESUMEN

The generation of identical droplets of controllable size in the micrometer range is a problem of much interest owing to the numerous technological applications of such droplets. This work reports an investigation of the regime of periodic emission of droplets from an electrified oscillating meniscus of a liquid of low viscosity and high electrical conductivity attached to the end of a capillary tube, which may be used to produce droplets more than ten times smaller than the diameter of the tube. To attain this periodic microdripping regime, termed axial spray mode II by Juraschek and Röllgen [R. Juraschek and F. W. Röllgen, Int. J. Mass Spectrom. 177, 1 (1998)], liquid is continuously supplied through the tube at a given constant flow rate, while a dc voltage is applied between the tube and a nearby counter electrode. The resulting electric field induces a stress at the surface of the liquid that stretches the meniscus until, in certain ranges of voltage and flow rate, it develops a ligament that eventually detaches, forming a single droplet, in a process that repeats itself periodically. While it is being stretched, the ligament develops a conical tip that emits ultrafine droplets, but the total mass emitted is practically contained in the main droplet. In the parametrical domain studied, we find that the process depends on two main dimensionless parameters, the flow rate nondimensionalized with the diameter of the tube and the capillary time, q, and the electric Bond number B(E), which is a nondimensional measure of the square of the applied voltage. The meniscus oscillation frequency made nondimensional with the capillary time, f, is of order unity for very small flow rates and tends to decrease as the inverse of the square root of q for larger values of this parameter. The product of the meniscus mean volume times the oscillation frequency is nearly constant. The characteristic length and width of the liquid ligament immediately before its detachment approximately scale as powers of the flow rate and depend only weakly on the applied voltage. The diameter of the main droplets nondimensionalized with the diameter of the tube satisfies d(d)≈(6/π)(1/3)(q/f)(1/3), from mass conservation, while the electric charge of these droplets is about 1/4 of the Rayleigh charge. At the minimum flow rate compatible with the periodic regimen, the dimensionless diameter of the droplets is smaller than one-tenth, which presents a way to use electrohydrodynamic atomization to generate droplets of highly conducting liquids in the micron-size range, in marked contrast with the cone-jet electrospray whose typical droplet size is in the nanometric regime for these liquids. In contrast with other microdripping regimes where the mass is emitted upon the periodic formation of a narrow capillary jet, the present regime gives one single droplet per oscillation, except for the almost massless fine aerosol emitted in the form of an electrospray.

14.
Biol Psychiatry ; 40(3): 189-202, 1996 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-8830952

RESUMEN

In this study the N400 of schizophrenics was compared with that of control subjects in a picture semantic-matching task. The comparison of N400 difference waveforms (subtraction of event-related potentials of congruent from those of incongruent trials) between control and patients was supplemented by separate analysis for congruent and incongruent trials. The N400 latency was delayed in patients. Also, the amplitude of N400 in the difference waveform was reduced in schizophrenics; however only congruent trials were different for patients (more negative) with respect to controls. This result is consistent with the hypothesis that schizophrenics use context poorly, but inconsistent with simple versions of the idea that associations are generally disinhibited in schizophrenia. Since the amplitudes of N400 and an auditory P300 were not correlated, a general processing deficit does not explain the results. Finally, by using picture matching, a cross-cultural comparison of N400 in schizophrenics from Cuba and China was possible, which indicated that the N400 abnormalities were similar in both groups.


Asunto(s)
Trastornos del Conocimiento/complicaciones , Trastornos del Conocimiento/diagnóstico , Potenciales Evocados , Esquizofrenia/complicaciones , Semántica , Percepción Visual , Adulto , China , Comparación Transcultural , Cuba , Femenino , Humanos , Masculino , Psicología del Esquizofrénico
15.
Free Radic Res ; 31 Suppl: S129-35, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10694051

RESUMEN

Two experiments were carried out to investigate if the supplementation with vitamin E affects refined olive oil response to oxidation regarding the stability of the oil and the protection in vivo against lipid peroxidation in rats after its intake in comparison with other edible oils. In experiment 1, samples of virgin olive oil, refined olive oil, refined olive oil supplemented by us with 200 mg/kg vitamin E, and sunflower oil were collected before and after a 60 min frying process. After frying, refined olive oil supplemented with vitamin E compared with the non-supplemented refined olive oil had a higher concentration of alpha-tocopherol (240.34+/-6.07 mg/kg vs. 131.94+/-8.14 mg/kg), more resistance against oxidation (19.01+/-1.88% vs. 10.6+/-2.08%) and less polar components (4.2+/-0.06% vs. 5.45+/-0.22%). In experiment 2, 24 male Wistar rats, divided into 4 groups, were fed on diets based on the same unfried oils (8% w/w) as in experiment 1, for 4 weeks. Two days prior to the end of the experiment, the rats were intraperitoneally administered with adriamycin (10 mg/kg/ day) to provoke an oxidative stress. The rats fed on refined olive oil plus vitamin E compared to the rats fed on non-supplemented refined olive oil had lower hydroperoxides concentrations (26.8+/-2.6 nmol/mg vs. 35.6+/-2.49 nmol/mg) higher coenzyme Q levels (128.1+/-11.97 pmol/mg vs. 81.25+/-9.25 pmol/mg) and higher alpha-tocopherol values (1.23+/-0.04 mmol/mg vs. 0.93+/-0.06 mmol/mg) in microsomes of liver. In conclusion, the supplementation of refined olive oil with 200 mg/kg of vitamin E increases the stability of this oil under pro-oxidant conditions, and its intake decreases the oxidative damage generated by adriamycin in rats.


Asunto(s)
Antioxidantes/administración & dosificación , Antioxidantes/química , Grasas Insaturadas en la Dieta/administración & dosificación , Aceites de Plantas/administración & dosificación , Aceites de Plantas/química , Vitamina E/administración & dosificación , Animales , Doxorrubicina/toxicidad , Estabilidad de Medicamentos , Calor , Peroxidación de Lípido/efectos de los fármacos , Masculino , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Aceite de Oliva , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar , Ubiquinona/metabolismo , Vitamina E/metabolismo
16.
Biofactors ; 9(2-4): 331-6, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10416049

RESUMEN

In this study we have evaluated the supplementation of olive oil with vitamin E on coenzyme Q concentration and lipid peroxidation in rat liver mitochondrial membranes. Four groups of rats were fed on virgin olive, olive plus 200 mg/kg of vitamin E or sunflower oils as lipid dietary source. To provoke an oxidative stress rats were administered intraperitoneally 10 mg/kg/day of adriamycin the last two days of the experiment. Animals fed on olive oil plus vitamin E had significantly higher coenzyme Q and vitamin E levels but a lower mitochondrial hydroperoxide concentration than rats fed on olive oil. Retinol levels were not affected, by either different diets or adriamycin treatment. In conclusion, an increase in coenzyme Q and alpha-tocopherol in these membranes can be a basis for protection against oxidation and improvement in antioxidant capacity.


Asunto(s)
Grasas Insaturadas en la Dieta , Suplementos Dietéticos , Doxorrubicina/toxicidad , Mitocondrias Hepáticas/metabolismo , Estrés Oxidativo/efectos de los fármacos , Aceites de Plantas/farmacología , Ubiquinona/metabolismo , Vitamina E/farmacología , Animales , Doxorrubicina/administración & dosificación , Ácidos Grasos/análisis , Inyecciones Intraperitoneales , Membranas Intracelulares/efectos de los fármacos , Membranas Intracelulares/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Lípidos de la Membrana/metabolismo , Mitocondrias Hepáticas/efectos de los fármacos , Aceite de Oliva , Estrés Oxidativo/fisiología , Aceites de Plantas/administración & dosificación , Ratas , Ratas Wistar , Vitamina E/administración & dosificación , Vitamina E/metabolismo
17.
Biofactors ; 9(2-4): 337-43, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10416050

RESUMEN

The mitochondrial theory of aging suggests that this phenomenon is the consequence of random somatic mutations in mitochondrial DNA, induced by long-term exposure to free radical attack. There are two potential dietary means of delaying the effects of free radicals on cellular aging, i.e., enrichment of mitochondrial membranes with monounsaturated fatty acids and supplementation with antioxidants. We have performed a preliminary study on male rats, 6 or 12 month old, fed with diets differing in the nature of the fat (virgin olive oil or sunflower oil) and/or with antioxidant supplementation (coenzyme Q10), analysing hydroperoxide and coenzyme Q9 and Q10 in heart mitochondria. Preliminary results allow us to conclude that the CoQ10 dietetic supplementation as well as the enrichment of the cellular membranes with monounsaturated fatty acids, successfully protect mitochondrial membranes from aged rats against the free radical insult.


Asunto(s)
Envejecimiento/fisiología , Antioxidantes/farmacología , Mitocondrias Cardíacas/efectos de los fármacos , Aceites de Plantas/farmacología , Ubiquinona/análogos & derivados , Animales , Coenzimas , Grasas Insaturadas en la Dieta/farmacología , Suplementos Dietéticos , Radicales Libres/metabolismo , Membranas Intracelulares/efectos de los fármacos , Membranas Intracelulares/fisiología , Masculino , Lípidos de la Membrana/metabolismo , Mitocondrias Cardíacas/fisiología , Aceite de Oliva , Estrés Oxidativo , Aceites de Plantas/administración & dosificación , Ratas , Aceite de Girasol , Ubiquinona/administración & dosificación , Ubiquinona/farmacología
18.
Rev Argent Microbiol ; 19(2): 71-6, 1987.
Artículo en Español | MEDLINE | ID: mdl-3503312

RESUMEN

The isolation of Yersinia enterocolitica from a child's feces with an acute diarrhea is reported for the first time in Argentina. The strain was classified as belonging to the biotype 4 of Wauters, serotype O:3, phage type VIII. The virulence-associated test of autoagglutination, calcium dependency and production of heat-stable enterotoxin were positive, whereas neither lethality for the adult mouse by oral route, nor invasiveness by using the Serény test in the mouse, were demonstrated. A plasmid of approximately 40 Mdal was detected. The suckling mouse LD50 was 4.1 x 10(6) cells. These characteristics are in agreement with those reported for most of the Yersinia enterocolitica strains belonging to the same serotype.


Asunto(s)
Diarrea/microbiología , Heces/microbiología , Yersiniosis/microbiología , Yersinia enterocolitica/aislamiento & purificación , Animales , Niño , Humanos , Masculino , Ratones , Yersinia enterocolitica/clasificación
19.
Arch Latinoam Nutr ; 50(1): 35-41, 2000 Mar.
Artículo en Español | MEDLINE | ID: mdl-11048569

RESUMEN

The purpose of the study was to evaluate the impact of a school breakfast program in Sonora, Mexico. The study was conducted in four counties classified as extremely poor. Three hundred children from twelve schools pertaining to three counties under research received a school breakfast; one hundred and fifty children from four schools pertaining to a fourth county did not received school breakfast. Children were four to six years old. Attention, memory and cognition tests were applied before and after the program. Results showed an improvement for those groups receiving the breakfast program, specially on response speed and behavior executions. Group without breakfast showed better results on the pre-test, nevertheless, on the post-test, performances in both groups appear the same. At the beginning of school courses any county was different, but speed in selection and running show significatives differences for the schools. The program shows similar results on response speed, no matter social condition, nevertheless, program differentially affects the number of correct behavior executions on stimulus selection and reproduction. The breakfast program benefit children, but its effects are differentially distributed improving behavioral, repertories depending of children's group vulnerability.


Asunto(s)
Atención , Ingestión de Alimentos , Memoria , Evaluación de Programas y Proyectos de Salud , Análisis de Varianza , Distribución de Chi-Cuadrado , Niño , Trastornos de la Nutrición del Niño/complicaciones , Preescolar , Cognición , Femenino , Humanos , Masculino , México , Estado Nutricional , Pobreza , Factores Sexuales
20.
Artículo en Inglés | MEDLINE | ID: mdl-23496458

RESUMEN

We study the motion of a particle in spatially periodic potentials with broken mirror symmetry under the influence of white α-stable Lévy noises. We consider both time-independent and fluctuating potentials. We focus on cases in which the spatial asymmetry of the potential is due not to a difference between the distances from an absolute minimum to the absolute maximum on its left and to the absolute maximum on its right but only to the curvatures of the potential profiles. The analysis is performed using the fractional Fokker-Planck formalism. Consistent results from Langevin simulations are also presented. We analyze the influence of the symmetry properties of the potentials in combination with the fluctuating characteristics of the system in the determination of the current. We find different situations in which both the absolute value and the direction of the current depend not only on the properties of the potential but also on the parameters characterizing the α-stable Lévy noise. Among other features, we analyze the case of supersymmetric potentials. In particular, we show that a static supersymmetric potential produces no current, and we analyze the conditions for observing a nonvanishing current when the potential fluctuates between different supersymmetric profiles.


Asunto(s)
Difusión , Modelos Estadísticos , Simulación por Computador , Movimiento (Física) , Estrés Mecánico
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