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D Colantonio

Publications and source records attributed to D Colantonio.

66 records · Page 4Linked to original sources
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[Atrial natriuretic peptide, renin-aldosterone system and arterial pressure. Analysis by circadian rhythm measurement].

Six voluntary, clinically healthy, non-smoking, male subjects were studied to estimate and eventually quantify the role of the circadian rhythm of atrial natriuretic peptide and of the renin-aldosterone system in the conditioning and genesis of the circadian rhythm of arterial blood pressure. After a week of standard life condition, during the span of a day, with the subjects in constant supine position, venous blood samples were drawn every four hours, while arterial blood pressure was measured every two hours. Plasma levels of atrial natriuretic peptide, renin activity, and aldosterone were determined by radioimmunoassay. The time-related values of each variable were analysed by the "cosinor" method. The cosinor analysis shows a statistically significant (p less than 0.05) circadian rhythm for all variables studied. These data suggest an inverse relationship between the circadian rhythm of atrial natriuretic peptide and that of arterial blood pressure, with a chronological sequence in the atrial natriuretic peptide-plasma renin activity-aldosterone axis.

Adult↗
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Plasma levels of atrial natriuretic peptide in compensated and decompensated cirrhosis of the liver. Relationship with the renin-aldosterone system.

The plasma levels of atrial natriuretic peptide (ANP) have been determined by direct radioimmunoassay in 36 clinically-healthy subjects, 24 patients with compensated cirrhosis of the liver, and 20 patients with cirrhosis and ascites. When compared with controls, plasma levels of ANP in compensated cirrhosis do not demonstrate a significant difference (p greater than 0.05). Patients with decompensated cirrhosis of the liver show significantly (p less than 0.001) higher levels of ANP with respect to the controls and to compensated patients. In the control group, a significant (p less than 0.001) negative correlation between plasma levels of ANP and plasma renin activity and plasma aldosterone is demonstrated. The patients without ascites do not present any correlation between these variables (p greater than 0.05). The patients with ascites show a significant (p less than 0.01) positive correlation between ANP and plasma renin activity and plasma aldosterone levels. These results and other data suggest that ANP, although appearing to have plasma levels correlated with the disease stage, and with increases in both renin activity and plasma aldosterone levels, does not seem to have a very important role in sodium retention, or in genesis of ascites in cirrhosis of the liver. Activation of the renin-angiotensin-aldosterone system, activation of the sympathetic nervous system, and the circulatory modifications as well as other mechanisms seem to be more important in the formation of ascites in cirrhotic patients.

Adaptation, Physiological↗
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[Evaluation of a morphologic staging method (myeloma progression score) in multiple myeloma].

One hundred twentyone cases of multiple myeloma were classified according to a myeloma progression score based on the relative frequencies of plasma cells and plasma blasts in bone marrow aspirate. A significant correlation was observed between calculated myeloma progression score and survival (p less than 0.001). Moreover, significant differences were found between mean survivals and survival curves in the three stages (p less than 0.01). The value of the method was limited by the non-uniform distribution of the patients in the three stage groups, at least in our study. These results confirm that the morphological scoring staging system is useful and reliable and that it can be successfully used as an additional system, together with clinical staging systems, for predicting survival in patients with multiple myeloma.

Adult↗
PubMedDate not supplied

[Proposal of a new staging system using scoring of multiple myeloma].

A new simple scoring staging system was developed and evaluated in 121 cases of multiple myeloma, followed from first diagnosis to demise. A score of 1 was assigned to each of the following features: bone marrow plasma cells more than 30%, hemoglobinemia less than 11 g/dl, lytic bone lesions of degrees 2-3, presence of Bence Jones proteinuria and serum beta 2-microglobulin levels higher than 8.0 micrograms/ml. Therefore, the score for each patient ranged from 0 to 5, corresponding to six risk classes: score 0 = class I; score 1 = class II; score 2 = class III; score 3 = class IV; score 4 = class V; score 5 = class VI. Since no differences in mean survivals and in survival curves were found between classes I and II, between classes III and IV and between classes V and VI, three stages could be devised: stage A (good prognosis) corresponding to classes I and II; stage B (intermediate prognosis) corresponding to classes III and IV; stage C (poor prognosis) corresponding to classes V and VI. Significant differences were found among the three stages regarding mean survivals, survival curves, and response to treatment. This scoring staging system is very simple in its formulation; only five routine parameters and no calculations are necessary for obtaining a score and consequently a stage for each patient. Moreover, the system can identify categories of multiple myeloma patients with homogeneous characteristics since it appears to be correlated with response to treatment and survival.

Adult↗
PubMedDate not supplied

[Reproducibility of a mathematical model for calculating survival in multiple myeloma].

The reliability of the mathematical model for calculating survival proposed by Merlini, Waldenstrom e Jayakar (1980) was tested in a group of 80 patients with multiple myeloma. The observed and calculated survivals were compared using univariate regression analysis. The results show that a significant (p less than 0.001) relationship between observed and calculated survival exists in the study patient group. These observations confirm that this useful and reliable clinical staging system can be a basis for individualization of a new treatment approach for each stage in order to reach an optimal treatment for multiple myeloma patients.

Adult↗
PubMedDate not supplied

[Circadian rhythm of human lymphocyte subpopulations].

Circadian rhythm of lymphocyte subsets was investigated in four healthy subjects, males, aged 35-58 years old. After a period of ambiental synchronization, venous blood samples were taken during a span of a day at 0.00 a.m., 4.00 a.m., 8.00 a.m., noon, 4.00 p.m. and 8.00 p.m. Lymphocyte subsets (OKT3, OKT4, OKT8, OKB7, OKJa1) were determined by monoclonal antibodies method, and serum level of cortisol by radioimmunoassay method. The OKT4/OKT8 ratio was also calculated. Data were analyzed by chronograms (mean +/- 1SD) and by cosinor method. Results show a significant circadian rhythm for each lymphocyte subset and for serum cortisol levels. The lowest levels of all circulating subsets were seen between noon and 4.00 p.m. and the highest levels around midnight, inversely related with the circadian rhythm of serum cortisol. The OKT4/OKT8 ratio, on the contrary, was relatively constant during the day, without a significant circadian rhythm. These observations have laboratoristic, clinical, and therapeutic implications and should be considered in the course of immunological studies.

Adult↗
PubMedDate not supplied

Essential hypertension, chronobiological study of the circadian variations in urinary excretion of free catecholamines.

Arterial blood pressure and urinary free catecholamine excretion of 8 hypertensive and 4 normotensive women have been evaluated by 3-h interval samples for 2 consecutive days. After noticing the effects of sleep on the arterial blood pressure and on the daily variation of urinary free catecholamine excretion, the authors examined the possible different role of the adrenergic system in hypertensive subjects.

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