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Biomedical subjects

S Sensi

Publications and source records attributed to S Sensi.

At least 73 records · Page 4Linked to original sources
PubMed1983

[1) Temporal structure of endocrine secretion: circannual changes in insulin responsiveness to tolbutamide in man].

In our previous observations we could detect the existence of circadian rhythms of either tolbutamide-induced insulin release with the acrophase early in the morning (at 04.20) or an insulin-induced hypoglycemia with the acrophase at 10.30 a.m. Aim of our work was to extend the observation to circannual rhythms of the same parameters. Four healthy young volunteers were submitted to the study in the early months of the year and observed in a 24 hrs-period, every other month, in the course of one year. 250 mg tolbutamide were injected i.v. in each day of the experiment every four hours with starting points at a random sequence. The data were analyzed by microscopic analysis: Halberg's Cosinor method. The highest insulin release occurred in winter (Acrophase: Jan. 19 with 95% confidence limits: Oct. 31 - April 1).

Adult↗
PubMed1983

[Circadian rhythm of ventilatory parameters of intrinsic asthma in clinical remission].

In six subjects with intrinsic asthma in clinical remission, time-structure of ventilatory parameters has been evaluated in order to evaluate: 1) which indexes present statistically significant circadian fluctuations; 2) if phase-shifts occur in comparison with normal subjects. After a period of synchronization of 7 days (L/D: 07.30-23.00; meal timing at 08.00, 13.00 and 20.30) all subjects have been studied by spirometry, flow-volume loop and Raw determination 6 times in a 24-hr period at constant intervals of 4 hrs. The results have been evaluated by macroscopic and microscopic analysis statistical significant fluctuations have been shown in these functional indexes: MEF50, Raw, SRaw, SGaw, FRC and RV; no phase-shifts occurred in comparison with normal subjects. On the contrary a circadian rhythm has not been shown in FVC, FEV1, and PEF. Therefore only the effort-independent test should be used to study correctly the bronchial tone.

Adolescent↗
PubMed1983

[The role of dietary carbohydrates and proteins in the determination of postprandial insulin requirements, evaluated by artificial pancreas, in type I diabetics].

Aim of this work is to evaluate the relative role of ingested carbohydrates and proteins in determining post-prandial insulin requirement in type I diabetic patients by means of artificial pancreas 5 male diabetics were given two times a day a diet with a high amount of carbohydrates (140g) or with a high amount of proteins (120g) while connected to the Biostator. Basal and post-prandial required insulin was evaluated. Post-prandial insulin requirement after high proteins meals did not appear greater than basal requirement, while insulin requirement after high carbohydrates meals appeared statistically greater than basal requirement. No difference could be observed between insulin requirement after morning (h. 10.00) or afternoon (h. 16.00) meals. These results could be of some help in optimizing the portable infuser-treated diabetic patients.

Adult↗
PubMed1983

[Biphasic response of insulin secretion to arginine stimulation: daily changes].

8 healthy subjects were infused with arginine at h. 08 and h. 16 of different days in order to observe if some changes occurred in the biphasic insulin response according with the different times of the day. A statistical difference between the two responses could be observed only for the first phase of the insulin response (time 0' - 10'), that appeared greater in the morning. When the insulin areas were plotted against the percentage of Ideal Body Weight an highly statistically significant correlation was found.

Adult↗
PubMed1983

[Chronobiological study of free thyroid hormones in hypothyroid and hyperthyroid subjects].

Previous reports demonstrate a circadian rhythm of the free thyroid hormones in healthy subjects. In this study we evaluated circadian variation of FT3 and FT4 in hyperthyroid and hypothyroid states. We considered six hyperthyroid patients, six hypothyroid patients and six control subjects. Blood samples were taken two hours apart from a catherterized arm vein. Data were evaluated by Halberg's cosinor analysis. The results show that FT3 and FT4 exhibit a circadian rhythm in healthy subjects, not evident in hyperthyroid and hypothyroid patients.

Adult↗
PubMed1982

[Circadian rhythm of platelet aggregation induced by adrenaline and collagen in man].

In five, healthy, male subjects the circadian variation of adrenaline and collagen induced platelets aggregation has been studied. Blood samples were carried out every four hours for a 24 hours period, platelets aggregation was evaluated on the P.P.P. by Elvi-Logos aggregometer adding adrenaline (1 mM/ml) or collagen (80 mg/ml). Cosinor test was used to detect circadian rhythms. A statistically significant circadian rhythm with peak in the morning has been demonstrated using both collagen or adrenaline. It is concluded that the adrenaline and collagen induced platelets aggregation "in vitro" shows a maximum of activity in the morning.

Circadian Rhythm↗
PubMed1982

[Chronotherapy of obesity. I. Effect of fenfluramine on the decrease of adipose mass in the obese, in relation to the time of administration].

In order to evaluate if a weight-reducing drug,-fenfluramine-(F.), administrated in different times of a day, provokes different rates of body weight reduction, it has been given in a group of obese patients according to 3 protocols: in the morning as a single dose of 80 mg. (Pr. M.); in the afternoon as a single dose of 80 mg. (Pr. A); and three times a day, at 08.00, 13.00 and 20.00 (Pr. T.T.). The administration of a single dose in the morning for 4 weeks provokes a higher decrease of body weight compared with the administration of the drug in the afternoon or three times a day for an equivalent period of time, (p less than 0.01; p less than 0,05). In addition the decrease in body weight appears significantly correlated with the decrease of adipose mass, obtained according to Hume and Weyers formulae. These preliminary results suggest to study the eating behaviour in order to observe if fenfluramine, which is known to affect the eating behaviour, changes its efficacy according to the time of administration and consequently its activity on body weight and adipose mass.

Adipose Tissue↗
PubMed1982

[Chronotherapy of obesity. II. Variations in eating behavior in the obese after fenfluramine treatment in relation to time of administration].

The administration of Fenfluramine (F.) in a single dose in the morning provokes a different effect on eating behavior (E.B.) in comparison with the administration of the same dose three times/day. It is observed a shorter duration of eating (p less than 001); a decrease of total kcalories ingested during the day, and hunger feeling. These results are reviewed on the basis of present knowledge on drug-kinetic and on previous work in our laboratory which documented higher decrease of body weight and adipose mass when the F. was administered in a single dose in the morning than in the afternoon or three times a day.

Adult↗
PubMed1982

[The TRH test in latent thyroid pathology].

TRH-test is an usefull tool for diagnostic purpose in thyroid disease. We challenged with TRH 4 groups of patients (1 degrees non toxic diffuse goitre, 2 degrees nodular goitre (Plummer's disease), 3 degrees euthyroid ophthalmic Graves' disease, 4 degrees hemithyroidectomy) with different thyroid affections who showed no symptoms and presented normal values of total thyroid hormones, in comparison with a control group. These groups displayed normal and pathological (blunted or absent and exaggerated) responses of TSH to TRH. Therefore TRH-test ra presents a good mean to recognize subclinical forms both hyperthyroidism and hypothyroidism.

Humans↗
PubMed1982

[Clinical significance of triiodothyronine (T3) measurement].

The clinical significance of T3 assay is related to the discovery of T3 thyrotoxicosis, a form of hyperthyroidism caused by an overproduction of alone T3 with normal value of T4. We evaluated the prevalence and the clinical features of this form in a group of 850 subjects who were submitted to clinical examination and hormonal thyroid assay. We showed that T3 thyrotoxicosis is a mild condition of hyperthyroidism.

Adolescent↗
PubMed1982

[Circadian rhythm of temperature, heart rate and blood pressure in normal rats and hypothyroid rats].

We explored the circadian variation of core temperature, heart rate and blood pressure in hypothyroid and euthyroid male Sprague-Dawley rats. A circadian rhythm was quantified by the population mean-cosinor method for the core temperature of both hypothyroid and intact rats, whereas for the blood pressure and heart rate values a circadian rhythm was validated by rejection of the zero-amplitude assumption only in the hypothyroid rats. Whether hypothyroid rats adjust to new schedules at a rate different from euthyroid animals is an inference from these studies awaiting scrutiny.

Animals↗
PubMed1982

[Desynchronization and resynchronization after west-east and east-west transmeridian flight].

Changes of some parameters of circadian rhythms (mesor, amplitude, acrophase) have been studied in healthy students and physicians during a double transmeridian flight : westward (Rome-Jakarta-Ambon Maluku Islands) and eastward direction (Ambon, Rome). In the present study, performed in November-December, both an acute effect of transmeridian flight on different variables particularly the rate of adaptation to local time, and a long-term effect have been studied. The following variables have been measured : 1) oral temperature (T.); 2) systolic blood pressure (S.B.P.); 3) diastolic blood pressure (D.B.P.) by automatic apparatus; 4) a memory test (M.) (a fixed number of playing cards in a fixed time); 5) eye-hand skull (E.H.S.) - the time necessary to order a fixed number of playing cards according to colour and suit; 6) fusion critical frequency (F.C.F.) of retinal vision. Measurements were performed at 4-hour intervals by autorythmometry. In conclusion it is possible to point out in this experience an asymmetry-effect in the adaptation of circadian rhythms according to the direction of flight : in the westward flight the acrophases of T, SBP and EHS approach, within 72 hrs, those previously observed before the beginning of the study, whereas in Jakarta, 24 hrs after the eastward flight the same variables maintain the same acrophases of Rome local time, within the first 24 hrs, and completely adjust to local time within ten day in Ambon.

Adaptation, Physiological↗
PubMed1982

[Measurement of energy expenditure through heart rate monitoring].

In studies of energy balance it is of utmost importance to measure with a certain degree of accuracy the energy expenditure. So far the energy cost has been measured by taking accurate diaries of various activities performed during a day. This study tries to find the possibility to measure the energy cost through heart rate, since it is correlated with oxygen consumption. In 17 obese and non obese healthy subjects the relation between oxygen consumption and heart rate has been studied minute by minute during various physical activities. Data show the existence of a very close relationship between the two variables demonstrating that continuous heart rate monitoring (dynamic ECG) may be considered as a valid tool for energy expenditure measurements. Since each subject shows his own linear equation, it is necessary to assess it before the measurement.

Adolescent↗
PubMed1981

[Effect of scheduling of meal times on the circadian rhythm of energy expenditure].

15 obese subjects were studied under different meal-timing schedules in order to see if meal-timing could affect the circadian pattern of energy expenditure. 4 subjects were given one meal (700 Kcal.) a day at h 10 in the morning (for 3 days) or at h 18 in the afternoon (for another 3 days). 4 subjects were given 3 meals (240 Kcal. each) at h 10, h14, h 18 for 3 days. 7 subjects were kept absolutely fasting for 36 hours. O2 consumption and CO2 production were measured minute by minute for 30' every 4 hours by means of a gas-analyser Mijnardht Oxicon II. Urine Samples were taken every 4 hours for urinary nitrogen determination. Energy expenditure was calculated according to Consolation's formula. Cosinor test was used to detect circadian rhythms. A statistically significative circadian rhythm of energy expenditure could be detected in all the protocols. The observed small differences among acrophases and the overlapping of confidence's ellipses allow to conclude that meal-timing doesn't affect the circadian rhythm of energy expenditure and suggest that this rhythm can be considered endogenous.

Adult↗
PubMed1981

[The artificial pancreas in the evaluation of insulin sensitivity in healthy subjects].

24-hours peripheral insulin sensitivity was studied in 5 healthy subjects by mean of artificial pancreas (Biostator), using the glycemic clamp technique (100 mg%). A sharp rise of insulin sensitivity (expressed as glucose required/insulin evoked ratio) was obtained in the morning, confirming our previous data observed by insulin tolerance test, but in a more physiological condition. The subjects appeared well synchronized as documented by statistically significant circadian rhythms in both serum cortisol and body temperature.

Adult↗
PubMed1981

[Treatment of unstable diabetes by continuous subcutaneous infusion of insulin].

In a group of seven brittle diabetic males, hospitalized, two kind of treatment has been compared: conventional insulin therapy (three daily injections) versus continuous subcutaneous insulin infusion. A strike improvement of metabolic control has been reached with the latter procedure. It is concluded that this new type of treatment seems very useful in brittle diabetics. The possible benefit on diabetic complications remains to be investigated.

Adult↗