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1.
Int J Biometeorol ; 68(3): 427-434, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38147120

RESUMEN

The aim of this study was to determine effects of parity (primiparous vs. multiparous), seasonal heat stress at calving (summer vs. winter), and time postpartum on some parameters associated with colostrum quality in Holstein cows reared in the Sonoran Desert ecosystem. Forty-seven cows (11 primiparous and 36 multiparous) expected to calve during summer, and 46 cows during winter (14 primiparous and 32 multiparous) were randomly selected. Management and feeding before and after parturition were similar for cows in both seasons. After parturition, colostrum from all cows was evaluated for volume, weight, temperature, density, and content of fat, protein, solids non-fat (SNF), and immunoglobulins (IGG). Data were analyzed with a model that included effects of parity status, calving season, and time postpartum, as well as all interactions. Colostrum produced in summer was warmer (P < 0.01) by almost 6 °C than winter colostrum, while colostrum from multiparous was warmer (P = 0.02) by 1.2 °C than that produced by primiparous cows. Colostrum volume and weight were not impacted by parity, calving season or time postpartum. Density, protein, and SNF content in colostrum were higher (P < 0.01) in multiparous vs. primiparous cows, as well as at parturition (0 h postpartum) than at 12 h postpartum (P < 0.01). At calving (0 h), spring colostrum had higher fat content (P < 0.01) and lower (P < 0.01) IGG concentration than that collected in summer, and no difference (P > 0.05) between seasons was observed for these components at 12 h postpartum. Multiparous cows produced colostrum with higher (P < 0.01) IGG concentrations than primiparous cows. In conclusion, only 0-h colostrum and that from multiparous cows was categorized as "Excellent," meanwhile the colostrum produced under summer heat stress was characterized as "Good" with reduced fat content. While the lacteal secretion collected at 12 post-partum still classified as colostrum, substantially lower contents of IGG, protein, fat, and SNF decreased its classification to "Poor" from the classification of "Excellent" at 0 h postpartum.


Asunto(s)
Calostro , Lactancia , Embarazo , Femenino , Humanos , Bovinos , Animales , Estaciones del Año , Leche , Ecosistema , Periodo Posparto , Inmunoglobulina G
2.
Rehabilitacion (Madr) ; 57(2): 100763, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36372588

RESUMEN

OBJECTIVE: Analysis of data collected in routine clinical practice of the combined impact of both physical activity and decrease in body mass index (BMI) on a minor prevalence of lymphedema in post-breast cancer patients. METHODS: Analysis of data obtained by the specialized rehabilitation unit, from 99 female patients for 18 months, after a specific diet, sports program and complete decongestive therapy (CDT) was indicated. Personal data, affected organ volume, weight, physical activity level and Functional Assessment of Cancer Therapy Questionnaire for Breast Cancer (FACT-B+4) were collected in follow-up visits. RESULTS: Although the average of body-mass index showed no change during the assessment period, about 13% of patients in the second follow-up visit and 30% in the third one had lost weight. Women experiencing weight-loss in the third follow-up visit presented a reduced volume of the affected organ [-50 (-248 to 141) ml vs. 130 (-148 to 355) ml, p<0.05] as compared to weight-gaining patients. No relationship was established between physical activity and lymphedema volume changes. CONCLUSIONS: Apart from the conventional treatment with orthotics and manual lymph drainage, BCRL prevention and treatment needs to focus - right from the start - on weight management or weight-loss in obese patients.


Asunto(s)
Neoplasias de la Mama , Linfedema , Femenino , Humanos , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/terapia , Drenaje , Linfedema/etiología , Linfedema/terapia , Modalidades de Fisioterapia , Drenaje Linfático Manual
3.
Am J Physiol Regul Integr Comp Physiol ; 318(2): R338-R350, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31850818

RESUMEN

Exposure to different stressors in utero is linked to adult diseases such as obesity and hypertension. In this study, the impact of prenatal infection (PNI) on adult body weight and cardiovascular function was evaluated using a naturally occurring rodent pathogen, Mycoplasma pulmonis (MP). Pregnant Sprague-Dawley rats were infected with MP on gestationalday 14 and gave birth naturally. Adult PNI offspring weighed more than controls, but resting mean arterial pressure (MAP) was unchanged. Subcutaneous injection of angiotensin II (10 µg/kg) elicited a rise in MAP that was greater in both male and female PNI offspring compared with controls (P < 0.03). The accompanying reflex bradycardia was similar to the controls, suggesting that PNI induced baroreflex dysfunction. Subcutaneous nicotine administration, a potent cardiorespiratory stimulus, also elicited a transient rise in MAP that was generally greater in the PNI group, but the change in MAP from baseline was only significant in the PNI females compared with controls (P < 0.03). Elevated body weight and cardiovascular reactivity in the PNI offspring was associated with an increase in the ratio of hypothalamic corticotrophin-releasing hormone receptors type 1 to type 2 gene expression in both sexes compared with controls. These findings support previous studies demonstrating that PNI induces alterations in cardiovascular function and body weight. Yet, unlike previous studies utilizing other models of PNI (e.g., endotoxin), MP PNI did not induce resting hypertension. Thus, our study provides a foundation for future studies evaluating the cardiovascular risks of offspring exposed to microbial challenges in utero.


Asunto(s)
Angiotensina II/administración & dosificación , Presión Arterial/efectos de los fármacos , Barorreflejo/efectos de los fármacos , Enfermedades Cardiovasculares/etiología , Infecciones por Mycoplasma/complicaciones , Mycoplasma pulmonis/patogenicidad , Efectos Tardíos de la Exposición Prenatal , Factores de Edad , Animales , Enfermedades Cardiovasculares/metabolismo , Enfermedades Cardiovasculares/fisiopatología , Modelos Animales de Enfermedad , Femenino , Edad Gestacional , Hipotálamo/metabolismo , Hipotálamo/fisiopatología , Inyecciones Subcutáneas , Masculino , Infecciones por Mycoplasma/microbiología , Embarazo , Ratas Sprague-Dawley , Receptores de Hormona Liberadora de Corticotropina/genética , Receptores de Hormona Liberadora de Corticotropina/metabolismo , Aumento de Peso
4.
Eur J Neurosci ; 46(3): 1875-1886, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28661071

RESUMEN

Travelling across several time zones requires a fast adjustment of the circadian system and the differential adjustment speeds of organs and systems results in what is commonly referred as jet lag. During this transitory state of circadian disruption, individuals feel discomfort, appetite loss, fatigue, disturbed sleep and deficient performance of multiple tasks. We have demonstrated that after a 6-h phase advance of the light-dark cycle (LD) scheduled food in phase with the new night onset can speed up re-entrainment. In this study, we explored the possible mechanisms underlying the fast re-entrainment due to the feeding schedule. We focused on first- and second-order structures that provide metabolic information to the suprachiasmatic nucleus (SCN). We compared (i) control rats without change in LD cycle; (ii) rats exposed to a 6-h phase advance of the LD cycle with food ad libitum; and (iii) rats exposed to the 6-h phase advance combined with food access in phase with the new night. We found an immediate synchronizing effect of food on stomach distention and on c-Fos expression in the nucleus of the solitary tract, arcuate nucleus of the hypothalamus, dorsomedial hypothalamic nucleus and paraventricular nucleus. These observations indicate that in a model of jet lag, scheduled feeding can favour an immediate shift in first- and second-order relays to the SCN and that by keeping feeding schedules coupled to the new night, a fast re-entrainment may be achieved by shifting peripheral and extra-SCN oscillations.


Asunto(s)
Ritmo Circadiano , Hipotálamo/fisiología , Síndrome Jet Lag/fisiopatología , Comidas/fisiología , Fotoperiodo , Animales , Conducta Alimentaria , Hipotálamo/fisiopatología , Masculino , Ratas , Ratas Wistar
5.
J Anim Sci ; 93(6): 3189-96, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26115305

RESUMEN

The aim of the present study was to evaluate the impact of zilpaterol hydrochloride (ZH; 0 or 10 mg/lamb daily) and soybean oil (SBO; 0 or 6%) supplementation on feedlot performance, carcass traits, and wholesale cut yield of 32 Dorper × Pelibuey ewe lambs (30.55 ± 2. 57 kg of initial BW). Lambs were blocked by BW and randomly assigned to treatments under a randomized complete block design with a 2 × 2 factorial arrangement. After a 34-d feeding period, all ewes were slaughtered. No ZH × SBO interactions were detected (P ≥ 0.11) for the variables evaluated. In the overall feeding period and first 17 d of experiment, feedlot performance was not affected (P ≥ 0.26) by ZH supplementation, but from d 18 to 34, ZH increased (P ≤ 0.03) total gain, ADG, and G:F without affecting DMI (P = 0.58). Also, ZH increased (P ≤ 0.02) HCW, cold carcass weight, dressing percentage, LM area, and leg perimeter. Lung weight as percentage of final BW decreased (P = 0.05) whereas other noncarcass components and wholesale cut yields were not affected (P ≥ 0.06) by ZH supplementation. Inclusion of SBO did not affect (P ≥ 0.08) feedlot performance or wholesale cut yields. The LM pH at 24 h postmortem as well as liver and peritoneum percentages were decreased (P ≤ 0.05) by SBO supplementation, but no other carcass characteristics or noncarcass components were affected (P ≥ 0.08) by SBO. In conclusion, feedlot performance and carcass characteristics were not altered by the interaction of ZH × SBO. However, ZH alone increased the growth of ewes during the last 17 d of the feeding period. Likewise, carcass characteristics of economic importance (i.e., HCW, dressing percentage, LM area, and leg perimeter) increased with ZH supplementation. In general, feedlot performance, carcass traits, and wholesale cut yields were not altered by including 6% of SBO in the finishing diet of ewe lambs.


Asunto(s)
Alimentación Animal/análisis , Suplementos Dietéticos , Ovinos/fisiología , Aceite de Soja/farmacología , Compuestos de Trimetilsililo/farmacología , Adrenérgicos/administración & dosificación , Adrenérgicos/farmacología , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Composición Corporal/fisiología , Peso Corporal , Dieta/veterinaria , Femenino , Hígado , Aceite de Soja/administración & dosificación
6.
J Anim Sci ; 92(12): 5762-8, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25403190

RESUMEN

The aim of this study was to evaluate effects of free ferulic acid (FA) supplementation on productive performance, some blood metabolite concentrations, and carcass characteristics of ewe lambs finished in a feedlot. Dorper×Pelibuey ewe lambs (n=20; BW=28.5±0.5 kg; age=5 mo) were individually housed in pens and assigned under a randomized complete block design to the following dietary treatments (n=10): daily feeding without (control) or with 300 mg of FA/animal. The feedlot feeding period lasted 34 d and then all ewe lambs were slaughtered. Free FA did not affect (P≥0.16) BW gain, ADG, DMI, and G:F during the first 17 d, but BW gain (P=0.10) and ADG (P=0.10) tended to decrease for FA from d 17 to 34 and from d 1 to 34 without affecting (P≥0.16) DMI and G:F in ewe lambs. Serum concentrations of glucose, cholesterol, triglyceride, total protein, and urea were not affected (P>0.05) by FA at d 1, 17, and 34 of the feeding period. Carcass characteristics were not affected (P>0.05) by FA. Stomach percentage tended (P=0.08) to decrease and leg yields increased (P=0.02) for FA. Other noncarcass components and wholesale cut yields were not affected (P>0.10) by FA. In conclusion, FA supplementation did not improve productive performance, metabolic status, and carcass characteristics of ewe lambs receiving a feedlot finishing diet.


Asunto(s)
Alimentación Animal , Glucemia/metabolismo , Composición Corporal/efectos de los fármacos , Colesterol/sangre , Ácidos Cumáricos/farmacología , Suplementos Dietéticos , Ovinos/fisiología , Animales , Antioxidantes/administración & dosificación , Antioxidantes/farmacología , Composición Corporal/fisiología , Peso Corporal/efectos de los fármacos , Peso Corporal/fisiología , Ácidos Cumáricos/administración & dosificación , Dieta/veterinaria , Femenino , Carne , Proteínas/metabolismo , Ovinos/crecimiento & desarrollo , Triglicéridos/sangre , Urea/sangre
7.
J Anim Sci ; 92(3): 1184-92, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24496845

RESUMEN

Forty Dorper × Pelibuey ram lambs initially weighing 31.7 ± 2.30 kg were stratified by BW and randomly assigned to treatments under a completely randomized design with a 2 × 2 factorial arrangement of treatments to evaluate effects of zilpaterol hydrochloride (ZH; 0 or 10 mg/lamb daily) and soybean oil (SBO; 0 or 6%) on feedlot performance, carcass characteristics, and wholesale cut yield of ram lambs under heat stress conditions. After a 34-d feeding period, all lambs were harvested. Climatic conditions were of moderate heat stress (average temperature 35.7°C) for lambs during the study. Interactions ZH × SBO were not observed (P ≥ 0.11) for any of the variables evaluated. During the first 17 d of experiment, ZH increased (P ≤ 0.05) BW, ADG, and G:F without affecting feed intake (P = 0.40), but from d 18 to 34 and the entire 34-d feeding period, feedlot performance was not affected (P = 0.18) by ZH. Also, ZH decreased KPH, dressing percent, LM area, LM pH at 24 h postmortem, and leg perimeter (P ≤ 0.04). Renal fat (P = 0.03) decreased with ZH while other noncarcass components were not affected (P ≥ 0.06) by ZH supplementation. Leg yield (P = 0.01) and plain loin (P = 0.04) decreased with ZH and yields of other wholesale cuts were not affected (P ≥ 0.10) by ZH. Feedlot performance (P ≥ 0.20) and wholesale cut yield (P ≥ 0.21) were not affected by SBO. Additionally, dressing percentage decreased (P < 0.01) with SBO while other carcass characteristics (P ≥ 0.12) were not affected by SBO. In conclusion, inclusion of both ZH and SBO in feedlot finishing diets did not improve feedlot performance, carcass characteristics, or wholesale cut yield of hair-breed ram lambs under moderate heat stress. Feedlot performance responded only to ZH and only during the first 17 d of the feeding period. In addition, some carcass characteristics of economic importance, such as dressing, LM area, and leg yield, were improved by ZH.


Asunto(s)
Composición Corporal/efectos de los fármacos , Calor/efectos adversos , Ovinos/fisiología , Aceite de Soja/farmacología , Estrés Fisiológico/efectos de los fármacos , Compuestos de Trimetilsililo/farmacología , Adrenérgicos/farmacología , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Suplementos Dietéticos , Masculino , Ovinos/clasificación , Aceite de Soja/administración & dosificación , Estrés Fisiológico/fisiología
8.
Environ Sci Pollut Res Int ; 21(9): 5909-16, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24453013

RESUMEN

Crops, particularly in the Northeast region of Mexico, have to cope with increasing soil salinization due to irrigation. Chloride (Cl(-)) concentration has been strongly related to enhance cadmium (Cd) uptake by plants due to increased solubility in the soil solution. The effect of irrigation with slightly saline water from a local well was evaluated in this work on the accumulation and translocation of Cd in Swiss chard (Beta vulgaris L.) grown in soil historically amended with stabilized sewage sludge under a regime of phosphorus and zinc fertilization. A factorial pot experiment was conducted with two phosphate fertilizer levels (PF, 0 and 80 kg ha(-1) dry soil, respectively), two Zn levels (0 and 7 kg ha(-1) dry soil), and two sources of water for irrigation deionized water (DW) and slightly saline well water (WW) from an agricultural site. Additionally, a human risk assessment for Cd ingestion from plants was assessed. Results showed that Cl(-) salinity in the WW effectively mobilized soil Cd and increased its phytoavailability. A higher level of Cd was found in roots (46.41 mg kg(-1)) compared to shoots (10.75 mg kg(-1)). Although the total content of Cd in the edible parts of the Swiss chard irrigated with WW exceeded permissible recommended consumption limit, bioavailable cadmium in the aboveground parts of the plant in relation to the total cadmium content was in the range from 8 to 32 %. Therefore, human health risks might be overestimated when the total concentration is taken into account.


Asunto(s)
Beta vulgaris/metabolismo , Cadmio/análisis , Cloruro de Sodio/química , Contaminantes del Suelo/análisis , Suelo/química , Zinc/química , Riego Agrícola , Agricultura , Restauración y Remediación Ambiental/métodos , Humanos , Raíces de Plantas , Medición de Riesgo
9.
J Anim Sci ; 91(4): 1844-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23345549

RESUMEN

Twelve Dorper × Pelibuey wether lambs (26.8 ± 1.6 kg initial BW, 5 mo of age) were used to evaluate effects of zilpaterol hydrochloride (ZH) on feedlot performance, and effects of ZH and ZH supplementation period (15 and 30 d) on nutrient intake and digestibility. Lambs were blocked by initial BW, and assigned randomly within BW blocks to 1 of 2 treatments: i) control (no ZH), and ii) supplemented with ZH (10 mg ZH/wether lamb daily). Measurements of intake and digestibility were performed on d 9 to 15 and 24 to 30. Feedlot performance data were analyzed as a randomized complete block design, and nutrient intake and digestibility data were analyzed as a randomized complete block design with a 2 × 2 factorial arrangement of treatments. Final BW, ADG, total BW gain, and G:F were greater (P ≤ 0.04) for ZH than for control lambs. No treatment × feeding duration interaction for nutrient intake and apparent total tract digestibility were observed (P > 0.05). Intake of DM, OM, CP, and GE were less (P ≤ 0.03) for ZH than for control. Lambs fed for 30 d had greater (P ≤ 0.04) NDF and GE intake compared with those fed for 15 d. Total tract digestibility of DM, OM, CP, EE, and ADF (P ≤ 0.03) was less for ZH than control. Furthermore, calculated DE, ME, and TDN intake decreased (P < 0.01) with ZH supplementation. Also, DM, CP, and ether extract(EE) digestibility were greater (P < 0.01) for 30 d than for 15 d. Additionally, greater (P ≤ 0.01) DE, ME, and TDN intake was observed for 30 d compared with 15 d. In conclusion, ZH supplementation of wether lambs consuming feedlot diets resulted in improved feedlot performance and reduced the intake and digestibility of some nutrients.


Asunto(s)
Agonistas Adrenérgicos beta/farmacología , Digestión/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Ovinos/fisiología , Compuestos de Trimetilsililo/farmacología , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Fenómenos Fisiológicos Nutricionales de los Animales/fisiología , Animales , Suplementos Dietéticos , Digestión/fisiología , Ingestión de Alimentos/fisiología , Masculino , Ovinos/crecimiento & desarrollo
10.
J Agric Food Chem ; 54(5): 1557-63, 2006 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-16506800

RESUMEN

Isotope dilution analysis (IDA) has been used to quantify total selenium, total solubilized selenium, and the selenomethionine (SeMet) amount in yeast and yeast-based nutritional supplements after acid microwave digestion and different enzymatic extraction procedures. For this purpose, both a (77)Se-enriched SeMet spike, previously synthesized and characterized in our laboratory, and a (77)Se(VI) spike were used. In the analysis of the nutritional supplements, the SeMet spike was added to the sample and extracted under different conditions, and the (78)Se/(77)Se and (80)Se/(77)Se isotope ratios were measured as peak area ratios after high-performance liquid chromatography (HPLC) separation and inductively coupled plasma mass spectrometry (ICP-MS) detection. The formation of SeH(+) and mass discrimination were corrected using a natural SeMet standard injected every three samples. Similarly, total solubilized selenium was measured in the extracts after enzymatic hydrolysis using the (77)Se-enriched SeMet as a spike by direct nebulization without a chromatographic separation. To establish a mass balance, total selenium was also determined by IDA-ICP-MS on the yeast tablets after microwave digestion using (77)Se(VI) as a spike. Results showed that all enzymatic procedures tested were able to solubilize total selenium quantitatively from the solid. However, the recovery for the species SeMet, the major selenium compound detected, was seriously affected by the enzymatic procedure employed and also by the matrix composition of the supplement evaluated. For the yeast sample, SeMet recovery increased from 68 to 76% by the combined use of driselase and protease. For the nutritional supplements, the two most effective procedures appeared to be protease and driselase/protease, with a SeMet recovery ranging from 49 to 63%, depending upon the supplement evaluated. In the case of in vitro gastrointestinal enzymolysis, the results obtained showed 26-37% SeMet recovery, while the rest of selenium was solubilized as other unknown compounds (probably Se-containing peptides).


Asunto(s)
Suplementos Dietéticos/análisis , Técnicas de Dilución del Indicador , Saccharomyces cerevisiae , Selenio/análisis , Selenometionina/análisis , Cromatografía Líquida de Alta Presión , Proteínas Fúngicas/metabolismo , Glicósido Hidrolasas/metabolismo , Isótopos , Espectrometría de Masas , Microondas , Péptido Hidrolasas/metabolismo , Selenio/metabolismo , Selenometionina/metabolismo
11.
J Agric Food Chem ; 51(18): 5296-300, 2003 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-12926873

RESUMEN

Several abiotic stresses, including ethylene, methyl jasmonate, temperature, light, and wounding, were tested for their ability to induce accumulation of phenolic compounds and antioxidant capacity in purple-flesh potatoes (cv. All Blue). Results indicated that temperature, ethylene, methyl jasmonate, and light treatments did not significantly affect the accumulation of phenolic compounds compared to control samples. Only tubers with low initial anthocyanin levels treated with methyl jasmonate showed approximately 60% anthocyanin accumulation. Wounding induced the accumulation of phenolics compounds and an increase of PAL-activity in sliced tissue compared to the control. Total phenolics increased approximately 60% with a parallel 85% increase in antioxidant capacity. These results show that selection of appropriate abiotic stresses can enhance the nutritional and functional value of potatoes.


Asunto(s)
Antioxidantes/análisis , Fenoles/análisis , Solanum tuberosum/química , Solanum tuberosum/fisiología , Acetatos/farmacología , Ciclopentanos/farmacología , Etilenos/farmacología , Oxilipinas , Enfermedades de las Plantas , Temperatura
12.
Arch Latinoam Nutr ; 51(3): 309-13, 2001 Sep.
Artículo en Español | MEDLINE | ID: mdl-11791485

RESUMEN

The objective of this study was the characterization of industrial nixtamalized maize flour for human consumption and which are marketed in Central America for some selected physical and chemical properties which may contribute to food composition information and help nutrition and micronutrient fortification programs. A total of 12 brands purchased in triplicate were obtained from supermarkets in Guatemala, El Salvador and Honduras. These samples were kept under refrigeration until analyzed. The physical parameters measured and results were the following: particle size with most samples having a high percentage of particles greater than 60 mesh, pH (5.4-7.5), water absorption index (WAI) (3.4-4.0 g gel/g sample), water soluble index (WSI) (4.8-7.8 g/100 g) and flour density (0.410-0.547 g/ml). The differences were statistically significant for all parameters measured, except for WAI. The chemical characteristics included, moisture, protein, fat, ash and dietetic fiber. Differences between flour samples were statistically significant except for fat content. Protein content was low, ranging between 6.7-8.1 g/100 g and total dietary fiber varied between 7.7-12.0 g/100 g. The samples were analyzed for phytic acid with a variation from 632 to 903 mg/100 g, with statistical significant differences. The samples were also analyzed for total and soluble (pH 7.5) iron, phosphorus, calcium, potassium, zinc, copper, manganese, and magnesium. The difference in the iron and calcium content between flour samples were statistically significant. The physical and chemical variability found between flour samples of nixtamalized maize was relatively high and it is recommended to establish quality standards through raw material and process standardization for greater effectiveness of nutrition programs and activities on micronutrient fortification which may be pursued in the future.


Asunto(s)
Harina , Manipulación de Alimentos/métodos , Zea mays/química , América Central , Alimentos Fortificados , Humanos , Valor Nutritivo , Control de Calidad
13.
Br J Nutr ; 83(2): 177-83, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10743497

RESUMEN

There is new evidence that a good folate status may play a critical role in the prevention of neural-tube defects and in lowering elevated homocysteine concentrations. This adequate folate status may be achieved through folic acid dietary supplementation. Folate is a water-soluble vitamin with a low potential toxicity. However, the possible consequences of long-term high-dose folic acid supplementation are unknown, especially those related to the methionine cycle, where folate participates as a substrate. With the aim of evaluating such possible effects, four groups of Wistar rats were classified on the basis of physiological status (virgin v. pregnant) and the experimental diet administered (folic-acid-supplemented, 40 mg/kg diet v. control, 2 mg folic acid/kg diet). Animals were fed on the diets for 3 weeks. Results showed that gestation outcome was adequate in both groups regardless of the dietary supplementation. However, there were reductions (P < 0.001) in body weight and vertex-coccyx length in fetuses from supplemented dams v. control animals. Folic acid administration also induced a higher (P < 0.01) S-adenosylmethionine: S-adenosylhomocysteine value due to increased S-adenosylmethionine synthesis (P < 0.01). However, hepatic DNA methylation and serum methionine concentrations remained unchanged. Serum homocysteine levels were reduced in supplemented dams (P < 0.05). Finally, pregnancy caused lower serum folate, vitamin B6 and vitamin B12 levels (P < 0.05). Folic acid administration prevented the effect of pregnancy and raised folate levels in dams, but did not change levels of vitamins B12 and B6. These new findings are discussed on the basis of potential benefits and risks of dietary folic acid supplementation.


Asunto(s)
Suplementos Dietéticos , Ácido Fólico/administración & dosificación , Metionina/metabolismo , Animales , Femenino , Peso Fetal/efectos de los fármacos , Ácido Fólico/sangre , Ácido Fólico/farmacología , Metilación , Estado Nutricional , Embarazo , Resultado del Embarazo , Ratas , Ratas Wistar , S-Adenosilmetionina/biosíntesis
14.
J Nutr ; 129(6): 1204-8, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10356088

RESUMEN

There is new evidence that good folate status may play a critical role in the prevention of neural tube defects and in the maintenance of adequate homocysteine levels, an amino acid recently identified as a risk factor for cardiovascular disease. This has led to different folate recommendations, all of them much higher than the present dietary recommendations. Folic acid is a water-soluble vitamin with a low potential toxicity. However, the possible consequences of long-term, high folate intakes are unknown. Therefore, the present study was undertaken to determine the effects of long-term, high dietary folate supplementation on gestational and nutritional markers in pregnant and virgin rats. Four groups of Wistar rats were classified on the basis of physiological status (virgin or pregnant) and the experimental diets administered (folic acid supplemented, 40 mg/kg diet; or control diet, 2 mg folic acid/kg diet). Rats were fed their respective diets for 3 wk. Two critical periods were used for metabolic balance studies (experimental d 1-5 and 17-21), which involved the determination of fat and protein digestibilities as well as metabolic protein utilization (MPU) and net protein utilization (NPU). Gestational development (number of live fetuses) was adequate in both diet groups regardless of folate supplementation. However, body weight and vertex-coccyx length in fetuses from supplemented dams were less than (P < 0.0001) in fetuses of control dams. Fat and nitrogen digestibilities were not affected by supplementation, but MPU and NPU coefficients were significantly lower (P < 0.05) in the folic acid-supplemented groups, irrespective of physiological status, compared to control rats. These new findings of macro-micronutrient interactions caused by high folate supplementation are discussed on the basis that the vitamin may act as a xenobiotic more than as a nutrient.


Asunto(s)
Proteínas en la Dieta/metabolismo , Feto/fisiología , Ácido Fólico/administración & dosificación , Preñez/metabolismo , Animales , Peso Corporal , Dieta , Desarrollo Embrionario y Fetal/fisiología , Femenino , Feto/anatomía & histología , Embarazo , Ratas , Ratas Wistar , Valores de Referencia
15.
Rev. méd. Hosp. Gen. Méx ; 55(3): 112-6, jul.-sept. 1992. tab, ilus
Artículo en Español | LILACS | ID: lil-118147

RESUMEN

La hiperprolactinemia secudaria a tumor hipotalámo es una patología poco frecuente de gran interés clínico. Se presenta el caso de una mujer de 32 añosde edad con padecimiento de siete meses de evolución manifestado por cefalea intermitente, disminución de la agudeza visual, amenorrea y galactorrea. Posteriormente inicia poliuria, polidipsia, hiperfagia, aumento ponderal y trastornos del sueño. a la exploración física se encontró defecto campimétrico visual, alteración de los pares craneales I, II, III y VII y lesión piramidal. Los estudios hormonales fueron compatibles con diabetes insípida y síndrome hiperprolactinémico. La tomografía computada evidenció la presencia de tumoración hipotalámica hiperémica con componenete quístico. La paciente fue intervenida quirúrgicamente, encontrándose tumor quístico de la línea media de la región hipotalámica, el cual no pudo ser extirpado en su totalidad, reportándose como diagnóstico anatomopatológico definitivo quiste epidermoide de la línea media. La evolución postquirúrgica de la paciente fue mala, fallecido 48 horas después de la cirugía.


Asunto(s)
Humanos , Femenino , Adulto , Amenorrea , Galactorrea , Hipotálamo/patología , Quiste Epidérmico/fisiopatología
16.
Arch Invest Med (Mex) ; 21(4): 393-8, 1990.
Artículo en Español | MEDLINE | ID: mdl-1669231

RESUMEN

Human spermatozoa and those obtained from mouse epididymis incubated in ethanolic from mouse epididymis incubated in ethanolic extracts of the cortex of Bursera fagaroides became agglutinated and immobilized in 100% with 30% of viability decrease. This double effect occurred in 50% of pig'ssperm and 50% of rabbit sperm when the concentration was increased tenfold. The pattern of progressive motility was affected 80% of rat's spermatocytes without agglutination. The values remained the same when the extracts were partially purified with salts of Zn++ and Ba++ or by filtration in a sephadex g-10 column. Analysis with thin layer chromatography of both purified extracts produced 3 compounds in comparison with the ethanolic unpurified extract. The extract of the plant Bursera fagaroides contains 3 compounds, which apparently are glycosides with a potent activity upon agglutination -immobilization and a low effect upon spermatocytes viability, which might be used as contraceptives .


Asunto(s)
Extractos Vegetales/farmacología , Aglutinación Espermática/efectos de los fármacos , Motilidad Espermática/efectos de los fármacos , Animales , Anticonceptivos Masculinos , Etanol , Humanos , Masculino , México , Ratones , Fitoterapia , Conejos , Ratas , Especificidad de la Especie , Porcinos
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