Effects of soy milk as a dietary complement during the natural aging process.

INTRODUCTION: Oxidative stress is one mechanism that could contribute to the acceleration of aging and age-related diseases. On the other hand, because of their antioxidative qualities soybean derived foods could have beneficial effects on the aging process. OBJECTIVES: The aim of our work was to study the effects of a diet supplemented with soy milk on certain biological features of aging in rats. METHODS: Male Wistar rats of 3 to 18 months of age, were assigned to one of two diets: 1) Experimental Group, commercial rat formula and soy milk; 2) Control Group, commercial rat formula and water. Every three months both lipid profile and lipid peroxidation were determined and neuronal cells of hippocampus were counted in control and experimental rats. RESULTS: The soy milk diet significantly improved the plasmatic lipid profile, decreasing serum cholesterol (total as well as LDL) and serum triglycerides, HDL-cholesterol was significatively higher in experimental animals. The LDL/HDL ratio was thus significantly lowered. The soy diet also produced decreased values of lipid peroxidation in brain, liver and kidney. These effects were significant after 6 to 9 months. The experimental animals lost fewer hippocampal neurons than the controls. Finally at 18 months of age, a greater number of surviving animals in experimental group with respect to the control one was observed. CONCLUSIONS: 1) soy intake could have beneficial effects as a complement of normal diet, but not as a replacement for animal proteins and 2) these effects are the result of a very long period (almost lifelong) of consumption of this diet.

Isolated congenital heart defects in first degree relatives of 185 affected children. Prospective study in Mexico City.

Parents (n = 355) and siblings (n = 313) of 185 index cases (IC) with congenital heart disease (CHD) were cardiologically evaluated. In the consecutive sample (2 years) Mendelian and chromosome syndromes were excluded. Four patients and nine siblings had CHD. The frequency of affection in siblings was 2.6% (8 in 313 siblings). All affected relatives are under medical care at the Centro Médico Nacional Siglo XXI, IMSS. In 10 of the 12 affected relatives found, the type of CHD was discordant from that of the IC. Discordance was found also in 9 of 36 IC with two or more CHD. An interpretation is given: if the mutated gene(s) has its effect in early embryological stages, affected relatives may have any type of CHD, but if the alteration occurs later, concordance is expected to be found. This model contributes also in explaining the remarkable genetic heterogeneity that exists in CHD.

[Early and late ligature of the umbilical cord and the acid-base equilibrium of the newborn infant]. / Ligadura temprana y tardía del cordón umbilical y el equilibrio ácido-base del recién nacido.

A comparative study was made between two groups of healthy newborns. In the first group (A), partial placental transfusion was propitiated and in the second group (B), the umbilical cord was ligated previous to the first inspiration. The behavior of the internal means was investigated carrying out a study of its acid-base equilibrium in umbilical vessels and in arterial blood of the newborn at 30 minutes of independent life. The analysis of the results confirmed significant statistical differences between both groups under study and the usefulness of one minute partial placental transfusion was substantiated. It verified besides that, although both groups showed similar behavior, the group where placental transfusion was propitiated showed a greater metabolic resource which was statistically confirmed. This circumstance propitiated a better accomplishment of homeostasis.

[Acid-base equilibrium in healthy newborns. Pattern of normality in Mexico City]. / Equilibrio ácido-base en recién nacidos sans. Patrón de normalidad para la ciudad de México

During their spontaneous recovery after birth, the acid-base balance was studied in 32 healthy newborns. The observation period lasted for 4 hours. Determinations were carried out, both in umbilical vessels as in central arterial blood. The most outstanding phenomenon was an increase in acidosis at 30 minutes of life. The metabolic component predominating over the respiratory was a definitely evident fact. At the end of four hours, the acid-base balance reached figures considered normal for the adult.

[Mechanism of adaptation of the newborn infant]. / Mecanismos de adaptación del recién nacido

An analysis of the mechanisms of adaptation of the newborn infant, immediately after birth, is put forth. Emphasis is placed upon cardiorespiratory and metabolic homeostasis, with a description of the internal medium variations in neonates seeking spontaneous equilibrium. In Mexico City this takes 4 hours. Hypoxia is stressed as one of the most important complications of the neonatal period, requiring rapid and efficient management of the infant to avoid severe complications or even death. Intra and extracardaic hemodynamic changes, stabilization of central arterial pressure as well as sufficient cardiac output, due to proper left ventricle function are described in reference to the cardiovascular sphere. A brief mention is made of the work of both ventricles during the first days of life. The diverse hemodynamic behaviour in different vascular areas of the newborn infant might be due to the concentrations of circulating gases, pH, enzyme factors and circulating hormones.