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R E Hernández

Publications and source records attributed to R E Hernández.

13 recordsLinked to original sources
PubMed1995

[Diabetes mellitus and hypertension, clinical and epidemiological aspects in the population of La Plata].

The purpose of this study was to determine socio-demographic characteristics, habits, most frequent morbid associations and degree of compliance with the control and treatment of their illness in a population of diabetic and hypertense patients of the La Plata area. A representative sample (890 people) was selected through a home survey (413 housing units). The results obtained show that diabetic and hypertense people a) are in average older than the general population and that the percentage of sedentary habits among them is also higher; b) show multiple typical symptoms of the illness but do not identify them as such and consequently diagnosis is frequently haphazardous; c) have a higher frequency of association with other risk factors, intercurrencies and hospitalization; d) are treated mainly by giving priority to drugs over changes in their detrimental habits; e) tend to ignore those indications that prescribe a change in their habits and f) control their illness at an inadequate periodicity. Consequently, it would be advisable to emphasize the incorporation of education strategies into the treatment of these patients in order to give more importance to preventive and health promoting actions. Education programmes should include not only patients and their families but also members of the health team and the community in general.

Adolescent↗
PubMed1985

Ultracytochemical nuclear calcium distribution in pancreatic B cells: its relation to glucose-stimulated insulin secretion.

Calcium distribution in pancreatic B cells was studied, with the aid of the pyroantimonate technique, at different times of glucose-induced secretory activity in the perfused rat pancreas. Specificity of the pyroantimonate precipitates for calcium was assessed by EGTA cross-incubation. Quantitative studies for these calcium pyroantimonate precipitates were performed by a morphometric technique. Pyroantimonate precipitates within the B cell show both time and glucose dependence. At any time-point studied, in the nucleus as well as in other organelles, they were more numerous when glucose was increased in the medium from 3.3 to 16.6 mmol/l. The total number of nuclear calcium pyroantimonate precipitates rose sharply at the time corresponding to the refractory period, falling after that to almost the number found at the prestimulatory period. Otherwise, glucose significantly modifies the temporal distribution of precipitates bound to euchromatin, heterochromatin and perichromatin. These changes in nuclear calcium pyroantimonate precipitates during different periods of B cell secretory activity may indicate an active role of the cation in some nuclear regulatory function during glucose-induced release of insulin.

Animals↗
PubMed1984

Sequential determination of calcium distribution in B cells at the various phases of glucose-induced insulin secretion.

Localization and quantification of calcium pyroantimonate precipitates within the B cells, and determination of insulin secretion were performed in rat pancreas perfused with 3.3 and 16.6 mmol/l glucose. Observations were carried out during the peak, the refractory period, and at 10 and 20 min in the second phase of glucose secretion after the start of a glucose challenge. Specific calcium pyroantimonate precipitates, assessed by EGTA cross-incubation, appeared attached to plasma membrane, Golgi complex, mitochondria, cytoplasmic matrix and secretory granules. The total number of cellular calcium pyroantimonate precipitates increased with perfusion time, being significantly higher at every time-point with the higher concentration of glucose (16.6 mmol/l) than with the 3.3 mmol/l glucose concentration. Calcium pyroantimonate precipitates showed a progressive increment both in plasma membranes and mitochondria. In the cytoplasmic matrix, B granules and Golgi complex, a sharp increase in the number of precipitates was detected at the refractory period, followed by a continuous decrease until the end of the experiment. These results show that the number of calcium pyroantimonate precipitates, localized in different organelles, changes according to the functional state of B cells. They stress the importance of intracellular readily exchangeable pools as regulators of calcium availability for insulin stimulus-secretion coupling.

Animals↗
PubMed1980

Streptozotocin-induced liver damage in mice.

Diabetes incidence and liver damage was studied and identified in C3H-s mice 21 days after Streptozotocin (SZ) administration (250 mg/kg/i.v.) at 04 hs (4 a.m.) and 16 hs (4 p.m.). Metabolic disturbances were assessed by daily control of glycosuria and serum glucose determined at the end of the experiment. Liver damage was controlled by light and electron microscopy. Both effects showed a circadian variation, with significant greatest values in the 16-h-injected group. Liver damage appeared whether the animals became diabetic or not, consisting in degranulation of the rough-surfaced endoplasmic reticulum, mitochondrial swelling with loss of cristae and edema of the ground substance, with flocculent amorphous precipitate. In some hepatocytes, a dilated cisternae of the endoplasmic reticulum was seen. It was concluded that: a) beta-cell and hepatocytes have a synchronic circadian sensitivity to SZ; b) liver damage was present whether the animals became diabetic or not, suggesting the presence of a different threshold for SZ effect in hepatocytes. These results might be taken into account when planning SZ use, either for experimental or clinical purposes.

Animals↗
PubMedDate not supplied

Prevalence of diabetes and obesity in an urban population of Argentina.

The prevalence of diabetes mellitus and obesity was studied in the urban area of La Plata City, Argentina. In the chosen population the age ranged from 20 to 74 years. Overt diabetics were not included in the study. For each individual, sex, age, weight, height, body mass index, (BMI), education, type of job and clinical and diabetic background were registered. Plasma glucose values were measured by reading Dextrostix strips in the Dextrometer, in samples obtained by finger punction 2 h after a 50-g glucose load. The final size of the sample (809 people), with an age and sex distribution similar to that of the general population, was attained at random, considering a diabetes prevalence of 6% in the population and a precision and confidence limit in the estimation of 2% and 95%, respectively. The results were evaluated using the post-load glucose values recommended by the World Health Organization (WHO) (200 mg/100 ml). According to these values, the prevalence of diabetes in our population was 2.7%. When adding the 2.3% of known diabetics to these figures, a prevalence of 5% was obtained. The value of the ratio of number of normal newborns/number of pregnancies significantly diminished as a function of the increment in the plasma glucose values found in the probands. Taking into account the BMI values, 37% of our sample population were obese subjects. Even when the glucose values obtained in obese subjects were within the normal range, they were significantly higher than those obtained in the nonobese group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗