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M M Esteban

Publications and source records attributed to M M Esteban.

32 records · Page 2Linked to original sources
PubMed1987

[Reflex pressure response to the electric stimulation of different parts of the rat stomach].

The role of the autonomic nervous system in the pressor response to the electrical stimulation of different gastric zones has been studied in rats. The stimulus was applied before and after the following interventions: bilateral vagotomy, ganglionic blockade, alpha-adrenergic receptor blockade and beta-adrenergic receptor blockade. After the ganglionic blockade no pressor responses to the electrical stimulus were observed. After the alpha-adrenergic blockade a lower pressor response was observed. A hypertensive response can be induced by mechanical, chemical or electrical stimulation of gastric receptors. It is concluded that the pressor reflex following the application of an electrical stimulus on different zones of the digestive tract is mediated by the sympathetic nervous system and that the efferent pathways are mainly alpha-adrenergic ones.

Adrenergic alpha-Antagonists↗
PubMed1987

Reflex pressor response to gastric mechanical stimulation in rats.

Neural and humoral mechanisms involved in the reflex pressor response during mechanical stimulation of the stomach of rats were investigated. The arterial blood pressure response was prevented by inhibition of alpha-adrenergic vasoconstriction using either an alpha-adrenergic blocker or a ganglionic blocker. In addition, there was a small decrease in the response after nephrectomy. However, there were no alterations in the response after beta-adrenergic blockade, bilateral adrenalectomy, inhibition of converting enzyme activity with enalapril or bilateral cervical vagus nerve transection. The heart rate was not modified after either intervention. After vagotomy the time of recovery of the basal blood pressure was significantly prolonged. It can be concluded that the blood pressure response to mechanical stimulation of the stomach wall is of neural rather than of humoral origin and mainly involves activation of alpha-adrenergic receptors. Vagal efferent pathways could be also involved.

Adrenalectomy↗
PubMed1987

Predominant right ventricular infarction in malignant renovascular hypertension in rats.

Malignant hypertension was induced in Wistar rats of both sexes by complete aortic ligature just above the origin of the left renal artery. An acute and a late phase of hypertension, 4 days and 28 days after the aortic ligature respectively, were defined to study the relationship between the severity of hypertension and injury of the small arteries and myocardial necrosis. The most frequent finding in the heart was the presence of right ventricular infarction. In acute-phase hypertension most of the animals showed acute infarction of the right ventricle, but only focal left ventricular infarction was found. Lesions in the large coronary arteries were not observed. However, the small arteries and arterioles of the right ventricle presented fibrinoid necrosis lesions. In late-phase hypertension, the intramyocardial small vessels showed proliferative endarteritis and fibrinoid necrosis lesions, but this time they appeared in both ventricles. The severity of the myocardial infarcts and the percentage of small arteries and arterioles injured in the right ventricle were significantly higher than in the left ventricle despite the maintenance of blood pressure almost to the same level. No changes in the right ventricular pressure were observed in either phase. These observations suggest that in malignant renovascular hypertension the intramyocardial arteriolar lesions appear to be an important factor in the production and the severity of myocardial infarcts with predominance in the right ventricle.

Animals↗
PubMed1986

Reduced ethanol consumption during cyproheptadine administration in rats from a long-term alcohol-treated colony.

The influence of cyproheptadine (CPH) on forced and voluntary ethanol intake was studied in long-term alcohol-treated rats. Wistar rats from a colony (WAC) that have been drinking alcohol as their only liquid fluid for the 25 previous generations and from a genetically related colony (WN) that had never been given alcohol were used. In the first experiment, daily IP doses of 15 mg/kg CPH were found to reduce forced ethanol consumption during CPH treatment in both WAC and WN rats which had been drinking ethanol for six months. In two additional groups of WAC and WN rats which were not given ethanol, water intake was not affected by CPH administration. In a second experiment, alcohol preference was reduced both during and after CPH, but total fluid intake (ethanol + water) was not affected. These findings suggest that the effect of CPH could be specific to ethanol. The decrease in ethanol consumption was associated with a significant body weight loss; this result may support the hypothesis of a link between the serotoninergic system, food intake, and alcohol drinking behavior that has been considered by earlier investigators.

Alcohol Drinking↗
PubMed1986

Allergy to white potato.

Allergy to potato is uncommon, and even more uncommon is allergy to potato pollen. The occurrence of both phenomena in the same patient made it possible to study cross-reactivity patterns of potato antigens. An 11-year-old girl, exclusively breast-fed for her first 4 months, developed anaphylactic symptoms after ingestion of potato at 5 months of age when she was fed potato for the first time. Subsequently, she developed urticaria, angioedema, and respiratory and systemic symptoms on contact with potatoes, ingestion of potatoes, and exposure to cooking potatoes or potato pollen. Three allergenic extracts from potato pulp, peel, and pollen were prepared. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate and isoelectrofocusing of the three extracts were performed. IgE-mediated allergy to these extracts was demonstrated by means of immediate skin test reactivity, positive passive transfer, RAST, RAST inhibition, and leukocyte histamine release. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the pulp extract followed by electroblotting and autoradiography demonstrated specific IgE antibodies directed against several proteins ranging from 14,000 to 40,000 daltons.

Child↗
PubMed1985

Blood pressure changes after gastric mechanical and electrical stimulation in rats.

The effect of different stimuli applied in several parts of the digestive tract on blood pressure was studied in unconscious Wistar rats. Gastric distension and electrical and pinching stimuli produced a significant increase in both systolic and diastolic arterial blood pressure. When different gastric zones were stimulated by either electrical or pinching stimuli, the highest pressor response was found in the antropyloric zone. The stimuli applied to the small intestine, outside the duodenum, did not modify the blood pressure. The pinching of the abdominal peritoneum caused a pronounced (P less than 0.001) blood pressure decrease. These data suggest that the pressor response to gastric distension could be mediated by gastric mechanoreceptors. The pressor response observed after stimulation of the gastric antropyloric zone suggests that this area has a greater number of mechanoreceptors.

Animals↗
PubMed1977

Oral disodium cromoglycate in food allergy. An open trial in four patients.

The effect of DSCG olution per os was studied in four infants with immediate hypersensitivity reaction to cow's milk and egg, manifested by digestive and cutaneous symptoms. Previous administration of a 1 per cent DSCG solution by mouth resulted in diminution of both the digestive and cutaneous symptoms associated with allergen challenge. The best time interval between oral DSCG and the allergen challenge was about 30 min. The drug lost effectiveness when the solution was prepared more than a week in advance of its administration. A 2-year follow-up in two of the patients revealed the reappearance of cutaneous and digestive symptoms and, for the first time, the onset of wheezing while continuing to administer the allergens and despite continuous oral DSCG. The characteristics of these cases raise questions about the means of sensitization, and the possible mechanism of action of oral DSCG in the inhibition of non-digestive symptoms. Clinical indications for its use are discussed.

Administration, Oral↗
PubMedDate not supplied

Sensitization to inhalant allergens in children diagnosed with food hypersensitivity.

In order to characterize the profile of inhalant allergen sensitizations in patients with food hypersensitivity, we carried out a screening process using a standard panel of inhalant allergens by SPT. We screened 437 patients (mean age 5.4 years, 4.1 SD) who showed anti-allergen IgE to one or several foods, determined by both SPT and RAST. In each case in which a positive SPT to inhalant appeared, a new individualized search for these allergens was performed by both SPT and Phadezym RAST. We found sensitization to aeroallergens in 272 of the 437 children (62%) with sensitization to foods (52% of all patients were sensitized to pollens, 17% to dermatophagoides, and 26% to animal allergens). The number with sensitization to aeroallergens was proportionally increased in relation to the number of food sensitizations (p < 0.05). Sensitization to pollen allergen were found with higher frequency (p < 0.001) in patients with sensitization to fruits, legumes, and other vegetables (mainly walnuts, chestnuts, melons, or sunflower seeds) than in those sensitive to foods of animal origin. Sensitization to dermatophagoides and animal allergens did not show any special distribution relative to the kind of food sensitization. Seventeen patients with sensitization to egg showed sensitization to avian feathers. This type of sensitization did not appear in the remainder of patients evaluated.

Allergens↗
PubMedDate not supplied

Normalization of the altered liver function tests after islet transplantation in diabetic rats.

The purpose of our study was to determine if streptozotocin induced diabetes (SID) in rats produces alterations in hepatic function, as described in poorly controlled diabetic patients, and if islet transplantation (islet-Tx) would subsequently ameliorate this status. Hepatocellular dysfunction was evaluated by the aspartate aminotransferase (SGOT) and the alanine aminotransferase (SGPT) activities in plasma. For the evaluation of cholestasis the plasma alkaline phosphatase (APase) activity was used. These determinations were performed in normal, SID, SID with Islet-Tx, and SID Wistar rats with sham-Tx. Also, glucose was measured in plasma samples, as well as histological studies of the liver were performed. More than 1,000 isogeneic islets (islet-Tx group) or non viable insular tissue (sham-Tx group) were transplanted via mesenteric ileal vein three weeks after SID. The results showed that SID in rats produces alterations in the hepatic function as well as in the structure of the hepatocytes, and the normalization of carbohydrate metabolism by islet transplantation restores normal hepatic function and morphology.

Alanine Transaminase↗
PubMedDate not supplied

[Functional health patterns and nursing diagnosis in intensive care units].

The evaluation of the critically ill patient to develop a suitable care plan is one of the main objectives of the practices of Medico-Surgery for students of third year of the nursing degree. So as to be able to detect all the needs in the patients and settle priorities in their care we have carried out a physical evaluation and the 11 health functional patterns of Gordon (1982), which has allowed us to formulate the most frequent diagnosis of nursing in the patients hospitalized in the Intensive Care Units of the Hospital Son Dureta of Palma de Mallorca. The collection of data for the evaluation of the patterns of autoperception, adaptation to stress and to the family, has been scarce due to the critical situation of the patient and the tendency of nursing professionals to register the evaluation data which indicate alterations of the physical condition of the patient. The incapacity for self-care and the risk for infection have been the nursing diagnosis which all the patients of this study have shown.

Critical Care↗