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1.
Acta Trop ; 255: 107214, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38663537

RESUMEN

Toxocara canis can produce the "larva migrans" syndrome in humans, and in puppies, it can cause severe digestive disorders. The most used treatments are based on anthelmintics, although there are reports of anthelmintic (AH) resistance. The Yucatan Peninsula has a great variety of plant species whose AH properties are still unknown. The objective of this study was to evaluate the in vitro AH activity of ethanolic (EE), methanolic (ME) and aqueous (AE) extracts from the leaves of five native plant species of the Yucatan Peninsula on T. canis eggs of dogs from Merida, Yucatan. As part of a screening, the EE of the plants Alseis yucatanensis, Calea jamaicensis, Cameraria latifolia, Macrocepis diademata, and Parathesis cubana were evaluated at doses of 2400 and 3600 µg/ml. The EE and AE of A. yucatanensis and M. diademata presented high percentages (≥ 91.3%) of inhibition of the larval development of T. canis after six days of exposure. The lowest LC50 and LC99 was presented by the ME from A. yucatanensis (255.5 and 629.06 µg/ml, respectively) and the ME from M. diademata (222.4 and 636.5 µg/ml, respectively), and the AE from A. yucatanenesis (LC50 of 535.9 µg/ml). Chemical profiling of the most potent AH extract (Alseis yucatanensis) was carried out by LC-UV-HRMS. Data from the ME and AE from this plant indicated the presence of the known glucosylngoumiensine, kaempferol 3,7-diglucosyde, uvaol, linoleic acid and linolenic acid together with unknown alkaloids. The EE, ME and AE from leaves of M. diademata and A. yucatanensis could be developed as natural alternatives to control T. canis.


Asunto(s)
Antihelmínticos , Extractos Vegetales , Hojas de la Planta , Toxocara canis , Animales , Extractos Vegetales/farmacología , Extractos Vegetales/química , Antihelmínticos/farmacología , Antihelmínticos/química , Toxocara canis/efectos de los fármacos , Perros , Hojas de la Planta/química , México , Larva/efectos de los fármacos
4.
Water Sci Technol ; 45(6): 187-98, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12046573

RESUMEN

We describe a framework in which a genetic algorithm (GA) and a static activated sludge (AS) treatment plant design model (WRC AS model) are used to identify low cost activated sludge designs that meet specified effluent limits (e.g. for BOD, N, and P). Once the user has chosen a particular process (Bardenpho, Biodenipho, UCT or SBR), this approach allows the parameterizations for each AS unit process to be optimized systematically and simultaneously. The approach is demonstrated for a wastewater treatment plant design problem and the GA-based performance is compared to that of a classical nonlinear optimization approach. The use of GAs for multiobjective problems such as AS design is demonstrated and their application for reliability-based design and alternative generation is discussed.


Asunto(s)
Algoritmos , Modelos Genéticos , Aguas del Alcantarillado/microbiología , Eliminación de Residuos Líquidos , Control de Costos , Arquitectura y Construcción de Instituciones de Salud , Nitrógeno/metabolismo , Oxígeno/metabolismo , Fósforo/metabolismo
5.
Br J Nutr ; 85(5): 549-52, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11348569

RESUMEN

The serum mineral levels, glucose disappearance rate (kg), total area under the glucose (DeltaG) and insulin (DeltaI) curves, and static insulin secretion were compared among rats fed a Mg-deficient diet for 6 (DF-6) or 11 (DF-11) weeks, and rats fed a control diet for the same periods (CO-6 and CO-11 groups). No change in glucose homeostasis was observed among DF-6, CO-6 and CO-11 rats. DF-11 rats showed an elevated kg and a reduced DeltaG and DeltaI. For evaluating the effect of supplementation, rats fed a control or Mg-deficient diet for 6 weeks were then fed a Mg- supplemented diet for 5 weeks (SCO and SDF groups respectively). The serum Mg levels in SDF rats were similar to those in CO-11 and SCO rats, but higher than in the DF-11 group. SDF rats showed similar kg, DeltaG and DeltaI compared with the CO-11 and SCO groups. However, a significantly lower kg and higher DeltaG and DeltaI were observed in SDF compared with DF-11 rats. Basal and 8.3 mmol glucose/l-stimulated insulin secretion by islets from DF-11 rats were higher than by islets from CO-11 rats. These results indicate that moderate Mg depletion for a long period may increase the secretion and sensitivity to insulin, while Mg supplementation in formerly Mg-deficient rats may prevent the increase in sensitivity and secretion of insulin.


Asunto(s)
Glucosa/metabolismo , Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Deficiencia de Magnesio/metabolismo , Animales , Área Bajo la Curva , Glucosa/farmacología , Homeostasis , Insulina/sangre , Secreción de Insulina , Islotes Pancreáticos/efectos de los fármacos , Magnesio/administración & dosificación , Masculino , Ratas , Ratas Wistar , Tasa de Secreción/efectos de los fármacos
6.
J Nutr ; 130(2): 133-8, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10720159

RESUMEN

Altered insulin secretion and sensitivity have been observed in Mg-deficient animals. However, the effects of Mg deficiency and supplementation on intracellular signaling events triggered by insulin are unknown. Therefore, we studied the early steps of insulin action in muscle and liver of rats fed Mg-deficient (DF-6, DF-11) or control (CO-6, CO-11) diets for 6 or 11 wk, respectively, and Mg-deficient or control diets for 6 wk, followed by Mg supplementation for 5 wk (SDF and SCO groups, respectively). There were no differences in the glucose disappearance rate (K(itt)) or insulin signaling between CO-6 and DF-6 rats. Between the two groups of rats fed for 11 wk, the DF-11 group had a significantly greater K(itt). SDF and SCO rats had K(itt) that did not differ from CO-11 rats, but that were significantly lower than in DF-11 rats. In the latter rats, insulin receptor and insulin receptor substrate-1 protein and phosphorylation levels were elevated in liver and there was a greater association between the insulin receptor substrate-1 and p85 subunit of phosphatidyl-inositol 3-kinase compared with CO-11 rats. There were no differences in the early steps of insulin action in SDF and control rats. These results suggest that the normal insulin sensitivity maintained by Mg supplementation and the increased insulin sensitivity produced by a long period of Mg deprivation may result, at least in part, from alterations in or maintenance of the early molecular steps of insulin action in hepatic tissue.


Asunto(s)
Insulina/fisiología , Hígado/metabolismo , Deficiencia de Magnesio/metabolismo , Magnesio/uso terapéutico , Músculos/metabolismo , Análisis de Varianza , Animales , Dieta , Electroforesis en Gel de Poliacrilamida , Glucosa/metabolismo , Hígado/efectos de los fármacos , Magnesio/administración & dosificación , Magnesio/sangre , Masculino , Músculos/efectos de los fármacos , Fosforilación/efectos de los fármacos , Ratas , Ratas Wistar , Receptor de Insulina/efectos de los fármacos
7.
Rev Paul Med ; 109(6): 265-8, 1991.
Artículo en Portugués | MEDLINE | ID: mdl-1668181

RESUMEN

Fiber rich cereal brans have been used for the therapeutic treatment of intestinal constipation. To improve acceptability and routine use, cookies were produced from fresh corn pericarp containing 23.3% of dietary cookies. The therapeutic effect of such cookies on simple intestinal constipation was evaluated. 8 individuals with chronic intestinal constipation and without other gastrointestinal diseases were selected. Each individual was given two diets, each of them during a seven day period: first, "normal diet" and, second, "normal" diet supplemented with 100 g of the cookies, i.e., with an increase of 23 g of dietary fiber per day. The cookies produced an increase in the frequency of evacuation (from 0.27 to 0.81 times/day), in fecal weight (from 38.3 to 117.4 g of feces/day), in water content of the feces (from 29.1 to 91.0 g of water/day), in the dry matter of the feces (from 9.1 to 26.4 g/day), and in the fiber content of the feces (from 1.59 to 8.52 g/day). As the addition of the cookies to the diet promoted increases in all fecal parameters studied, they could be considered an option in the treatment of intestinal constipation.


Asunto(s)
Estreñimiento/dietoterapia , Fibras de la Dieta/administración & dosificación , Enfermedad Crónica , Heces , Alimentos Formulados/análisis , Humanos , Zea mays
9.
Birth Defects Orig Artic Ser ; 13(2): 41-58, 1977.
Artículo en Inglés | MEDLINE | ID: mdl-213140

RESUMEN

Normal male genital differentiation requires fetal testicular secretion of both testosterone and the nonsteroidal müllerian-inhibitory factor. It appears that secretion of testosterone, at least during the critical period of differentiation, occurs in response to stimulation by CG, although pituitary LG may influence Leydig cell function in later fetal life. To date, there is no evidence to support a similar endocrine function for the fetal ovary in female genital differentiation. In both sexes normal fetal pituitary gonadotropin secretion appears to be required for maturation of the germ cells and related elements. The pattern of FSH and LH secretion in the fetus reflects gradual maturation of a functional hypothalamo-pituitary unit responsive to feedback inhibition by sex steroids. The higher levels of gonadotropins in female fetuses from from 12--20 weeks suggest either that this maturation occurs earlier in males than in females, or, more probably, that feedback recognition of androgens is established before gestation reflects development of an estrogen-mediated feedback mechanism, and in addition the possible influence that hormones, such as prolactin or placental estradiol, may have on testicular steroidogenesis.


Asunto(s)
Feto/metabolismo , Genitales/embriología , Hormonas Esteroides Gonadales/biosíntesis , Gonadotropinas/fisiología , Andrógenos/sangre , Andrógenos/metabolismo , Estrógenos/sangre , Estrógenos/metabolismo , Femenino , Hormona Liberadora de Gonadotropina/fisiología , Humanos , Hipotálamo/fisiología , Masculino , Morfogénesis , Ovario/embriología , Hipófisis/fisiología , Receptores de Superficie Celular , Diferenciación Sexual , Testículo/embriología
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