The addition of glucose to a suspension of yeast initiated glycogen synthesis and ethanol formation. Other effects of the glucose addition were a transient rise in the concentration of cyclic AMP and a more prolonged increase in the concentration of hexose 6-monophosphate and of fructose 2,6-bisphosphate. The activity of glycogen synthase increased about 4-fold and that of glycogen phosphorylase decreased 3 -5-fold. These changes could be reversed by the removal of glucose from the medium and induced again by a new addition of the sugar. These effects of glucose were also obtained with glucose derivatives known to form the corresponding 6-phosphoester. Similar changes in glycogen synthase and glycogen phosphorylase activity were induced by glucose in a thermosensitive mutant deficient in adenylate cyclase (cdc35) when incubated at the permissive temperature of 26"C, but were much more pronounced at the nonpermissive temperature of 35°C. Under the latter condition, glycogen synthase was nearly fully activated and glycogen phosphorylase fully inactivated. Such large effects of glucose were, however, not seen in another adenylate-cyclase-deficient mutant (cyrl), able to incorporate exogenous cyclic AMP.When a nitrogen source or uncouplers were added to the incubation medium after glucose, they had effects on glycogen metabolism and on the activity of glycogen synthase and glycogen phosphorylase which were directly opposite to those of glucose. By contrast, like glucose, these agents also caused, under most experimental conditions, a detectable rise in cyclic AMP concentration and a series of cyclic-AMP-dependent effects such as an activation of phosphofructokinase 2 and of trehalase and an increase in the concentration of fructose 2,6-bisphosphate and in the rate of glycolysis. Under all experimental conditions, the rate of glycolysis was proportional to the concentration of fructose 2,6-bisphosphate. Uncouplers, but not a nitrogen source, also induced an activation of glycogen phosphorylase and an inactivation of glycogen synthase when added to the cdc35 mutant incubated at the restrictive temperature of 35 "C without affecting cyclic AMP concentration.Glycogen tends to accumulate in yeast in conditions under which growth is restricted. This is the case during the transition between the exponential and stationary phases of growth in the presence of glucose [l -51 and also during incubation of yeast in a medium containing glucose but devoid of other essential elements such as nitrogen [3, 5-71, phosphate or sulfate [3]. Conversely, the addition of a nitrogen source to a nitrogen-deficient medium causes a sudden arrest of glycogen accumulation and stimulates glycolysis [2, 5 -71. Besides these nutritional factors, several drugs are also known to affect glycogen metabolism. Indeed, uncouplers such as 2,4-dinitrophenol and azide have the property of inducing a rapid degradation of the polysaccharide when added either alone or even in the presence of glucose to a yeast suspension [7-111.

Asymmetry was a prevalent feature in the present sample, and preferences for symmetric faces were not operating in the studied population.

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Objetivos. Evaluar la seguridad alimentaria y nutricional en familias del distrito Los Morochucos en Ayacucho, Perú. Materiales y métodos. Estudio basado en interpretación de la información disponible de fuentes oficiales y de encuestas realizadas para levantar la información no registrada en ellas. El muestreo fue estratificado y bietapico considerando 128 familias con al menos un niño menor de 12 años. Las variables fueron el nivel de seguridad alimentaria, percepción familiar sobre su situación de disponibilidad y acceso de sus alimentos, lactancia materna exclusiva, alimentación durante episodios de diarrea, frecuencia de consumo de alimentos, consumo de agua segura, lavado de manos, servicios higiénicos adecuados, estabilidad en el suministro de alimentos, estado nutricional y de salud, desnutrición crónica, anemia y parasitosis en niños de 6 meses a tres años. Resultados. El 39,1% de familias tiene seguridad alimentaria, 37,5% inseguridad alimentaria sin hambre, 18,8% inseguridad alimentaria con hambre, y 4,7% inseguridad alimentaria con hambre severa. Tienen aceptable consumo de calorías, pero no tienen una dieta balanceada. No cuentan con agua clorada. Durante los episodios de diarrea, 72% de madres alimenta al niño con mates o caldos. Se perdieron gran cantidad de sus cosechas el año 2011. Los niños de 6 meses a tres años presentan 34,5% de desnutrición crónica, 42,4% de anemia y 61,6% parasitosis. Conclusiones. La inseguridad alimentaria y nutricional en este distrito de Ayacucho es considerable debiéndose priorizar la ejecución de proyectos de inversión con el fin de contribuir el desarrollo de la comunidad.