Biomedical subjects

P Cugini

Publications and source records attributed to P Cugini.

At least 55 records · Page 3Linked to original sources

PubMed1996

Circadian rhythms in human body composition.

The study investigates how the human body composition (BC) changes as a function of the day-night cycle. The BC was investigated using bioelectrical impedance analysis (BIA) of 10 clinically healthy subjects (CHS), monitored in supine position (readings at 2-h intervals), avoiding mealtimes, dietary abuses, and bladder and intestinal retention. Time series data were analyzed for their temporal characteristics and circadian rhythm (CR). All the variables of BC (lean body mass, fat body mass, body cell mass, total body water, intracellular and extracellular body water, sodium and potassium exchangeable pool) showed a within-day variability with nighttime crests. Such an oscillatory synchronism corroborates the hypothesis that the rest time plays a fundamental role, via its anabolic effects, in conferring the nocturnal phase to the CR of the human BC.

Adipose Tissue↗

PubMed1996

[The treatability of refractory or resistant hypertension by personalized antihypertensive chronotherapy based on ambulatory monitoring of the arterial pressure].

The present paper is aimed at detecting whether the combination of ambulatory blood pressure monitoring (ABPM) and antihypertensive chronotherapy can be usefully exploited in the treatment of hypertension which appears to be rebel or resistant to pharmacological administration. The study was carried out in 28 hypertensive patients (15 men and 13 women, 45 +/- 10 years old), rebel (10 cases) or resistant (8 cases) to a conventional antihypertensive therapy. The ABPM was performed weekly in order to see when the eventual patient was cured by the therapy which was synchronized to the "relative hypertensive peak" of the antimeridian, postmeridian and nocturnal part of the day. The actuarial analysis documented that at the end of the sixth week no case remained rebel or resistant to the antihypertensive chronotherapy, suggesting that the combination of the ABPM with the chronotherapeutical treatment is highly recommended in presence of apparently refractory cases of hypertension.

Adult↗

PubMed1996

Atrial natriuretic peptide in normotensive and hypertensive heart transplanted patients.

AIM OF THE STUDY: The present study is aimed to investigate the 24-hour pattern of Atrial Natriuretic Peptide (ANP) plasma concentration in normotensive (N) and hypertensive (H) heart transplanted patients (HTP) in order to detect the pathophysiological role of blood pressure regimen for ANP increase in HTP. METHODS: Eight NHTP and five HHTP have been investigated, all being hemodynamically compensated, without histological evidence of rejection and treated by Cyclosporine, Azathioprine and Prednisone. The control group was constituted by 10 clinically healthy subjects (CHS). ANP was assayed six times over the 24 h span. The contrasts between groups were statistically analyzed by means of Student's t-test for the 24 h mean values. RESULTS: The t-test found a statistically significant difference between the ANP 24 h mean levels either of CHS and HTP or NHTP and HHTP. The ANP 24 h mean plasma levels are increased of 190.4% in HHTP and of 44.3% in NHTP in comparison with CHS. DISCUSSION: The findings suggest that the further elevation of ANP in HHTP is a compensatory mechanism to antagonize high blood pressure. Moreover, being the ANP percent increase in HHTP three times more.

Adult↗

PubMed1996

Circadian rhythm of blood pressure and life style: a study of clinically healthy subjects living in rural and industrialized countries.

The aim of this study is to investigate how the blood pressure (BP) circadian rhythm (CR) is influenced by life style. Two groups of subjects were recruited from Nepal and Japan because of the extremely different occupational routines of these countries. The Nepalese represent a rural culture, while the Japanese reflect an industrialized civilization. Both the ethnic groups have in common a high dietary sodium intake. The BP monitoring was estimated according to chronobiological methods. Results provide evidence for a phase difference in BP CR which is coherent with the life style in the two groups. Furthermore, the estimates demonstrate that the Japanese show a higher level in daily BP which is related to the greater number of hours in which they are active. These findings may be taken into account for better deciphering of what is the role of life style on BP physiology in human beings.

Adolescent↗

PubMed1996

Evidence from a chronobiometric approach that chronic smokers, although normotensive, show an increase in diurnal blood pressure.

OBJECTIVE: To investigate the effects of chronic smoking on the 24 h blood pressure and heart rate pattern in normotensive subjects. METHODS: Twenty-five smokers and 25 age-, weight- and height-matched non-smokers, who were all clinically healthy young men, gave their informed consent to undergo non-invasive, automated, ambulatory blood pressure monitoring for 24 h. The smokers in this study consumed on average 25.4 cigarettes per day. The lifestyle of the two groups was comparable because they worked as clerks at the same company. The 24 h blood pressure and heart rate data were analysed according to chronobiological methods. RESULTS: Smokers were found to show a statistically significantly higher blood pressure versus non-smokers by day but not by night. Furthermore, smokers showed a slight increase in the mean level of circadian blood pressure rhythm versus non-smokers, accompanied by an amplification of one cyclic component of this periodicity. CONCLUSIONS: The increase in diumal blood pressure in smokers might be regarded as the haemodynamic effect of chronic smoking in normotensive subjects. Such an effect seems to be substantiated pathophysiologically by an amplitude overmodulation of one of the harmonic components which confer the circadian blood pressure rhythmicity. Because the diumal increase in blood pressure persists for two-thirds of the day-night period, one can argue that this phenomenon in normotensive smokers might be a premonitory sign of future hypertension. Apart from this, one can hypothesize that the diumal increase in blood pressure might itself be a cause of target organ damage, given its consistent within-day duration and daily repetition.

Adult↗

PubMed1996

[Describing and interpreting systemic hypertension in heart transplantation with non-invasive arterial pressure monitoring].

This investigation was performed in 34 heart transplanted patients (HTP), 28 males and 6 females, mean age 49 +/- 13 years. The aim of the study was to detect hypertension in HTP by casual sphygmomanometry and non-invasive ambulatory blood pressure monitoring (ABPM). The evaluation of ABPM demonstrated that 71% out of the HTP was hypertensive because of some elevated blood pressure values scattered during the hours of the day and/or of the night. These hypertensives were found within the groups of normotensives as well as of hypertensives considered to be correctly treated. Fifty percent hypertensive HTP did not show the physiologic nocturnal decrease in blood pressure (non-dippers); 25% out of the non-dipper hypertensives showed absence of the blood pressure circadian rhythm, demonstrating that their hypertension was prevalently nocturnal and could not be detected by casual sphygmomanometry-The ABPM is recommended in clinical follow-up of HTP for a correct diagnosis of hypertension, which frequently complicates heart transplantation, and with the aim of avoiding hypertensive damage of the transplanted organ. The ABPM is useful for adjusting the antihypertensive therapy, in order to restore the blood pressure circadian rhythm.

Adult↗

PubMed1996

[Hypertensive cardiac damage in heart transplantation. A noninvasive monitoring study of arterial pressure].

This study is aimed at investigating the relationship between cardiac hypertrophy and blood pressure (BP) 24-h pattern in 34 heart transplanted patients (HTP), 9 out of them (26%) being considered as normotensives, the other ones (74%) being regarded as hypertensives under adequate treatment, via casual sphygmomanometry. The study is an attempt to explain the occurrence of at least one sign of hypertrophic cardiopathy in 20 cases (59%), hypothesizing the presence of false normotensives among the putative normotensives and presumably-cured hypertensives. The ambulatory BP monitoring was able to identify 7 hypertensives (78%) among the putative normotensives, and 17 not well-cured subjects (68%) among the presumably cured hypertensives. At least one sign of cardiac hypertrophy was found in 5 (50%) of the 10 true normotensives, who were all non-dipper, and in 15 (63%) of the 24 hypertensives. The 9 hypertensives without cardiac hypertrophy (37%) had developed hypertension very recently. These findings stress the role of the ambulatory BP monitoring as a diagnostic tool during the follow-up of HTP, in order to identify the false normotensives as well as the not well-treated hypertensives. This role can contribute to optimize the prophylaxis of hypertensive damage for the transplanted heart.

Adult↗

PubMed1996

[The heart rate variability indices and the circadian rhythm of the hourly heart rate: 2 prognostic indicators of mortality and malignant ventricular arrhythmias in patients with a myocardial infarct].

The aim of this study was to investigate the circadian variability of heart rate in acute myocardial infarction (AMI) in identifying patients at high risk for malignant ventricular arrhythmias (MVA) and sudden death within 1 year of the acute event. The investigation was carried out in 43 patients, who underwent 24-hour Holter monitoring within 3 months of AMI. Besides the time domain indexes of heart rate variability (SDNN, SDNN index, pNN50, rMSSD), the circadian rhythm of hourly total beats (HTB) and hourly qualified beats (HQB) has been analyzed by the Cosinor method. The AMI patients with MVA and those with MVA who died within 1 year the acute event showed SDNN, SDNN index and pNN50 values lower than subjects without MVA and survived patients with MVA, respectively; the individuals with AMI at high risk for MVA and for sudden death had an SDNN value < 105 ms and 50 ms, respectively. The circadian rhythm of HTB and HQB was statistically validated only in the group without MVA; patients without the circadian rhythm of HTB and HQB showed a higher mortality rate within 1 year of AMI, and the majority was in the group with MVA. The contemporary evidence of an SDNN value < 105 ms and the lack of HTB and HQB circadian rhythm increased sensitivity for identifying patients with MVA to 75%. On the other hand, the contemporary evidence of an SDNN value < 50 ms and the lack of HTB and HQB circadian rhythm increased sensitivity for identifying patients who died within 1 year of AMI to 100%. In conclusion, the assayed methods seem to be both useful and complementary in identifying patients at high risk for MVA and sudden death within 1 year of AMI.

Aged↗

PubMed1995

Chronobiometric identification of disorders of hunger sensation in essential obesity: therapeutic effects of dexfenfluramine.

In human beings, hunger is a proprioceptive signal that shows intraday (circadian components) and within-day (ultradian components) recursivity. Both periodic components can be investigated by chronobiometric procedures by combining the Cosinor method with spectral analysis. A 24-hour profile of hunger sensation (HS) can be plotted on a 1-to-10 scale of intensity using self-rated scores performed every half-hour of the day. Circadian and ultradian components were studied in 60 patients affected by essential obesity (20 men and 40 women; mean age, 38.4 years; mean body weight, 101 kg) before and after treatment with dexfenfluramine (Isomeride; Servier, Orléans, France) 15 mg orally twice daily, for 30 days. The control group consisted of 30 clinically healthy subjects (15 men and 15 women; mean age, 37.5 years; mean body weight, 69 kg). Chronobiometric analysis shows three patterns in obese patients, which suggests that HS may be normal (eurectic obesity), exaggerated (hyperrectic obesity), or diminished (hyporectic obesity). After dexfenfluramine administration, HS was showed a substantial decrease in the daily mean level. The spectrum of resolution in circadian and ultradian components was found to be maintained in eurectic obesity and partially readjusted in hyperrectic and hyporectic obesities. This demonstrates that dexfenfluramine acts not only as an anorectic but also as a chronizer by interfering with the recursive components of HS. The anorectic and chronizing effects suggest that dexfenfluramine is a "chronoanorectic drug" that interacts with the chronobiologic properties of the serotoninergic system.

Adult↗

PubMed1995

Association of body mass index and regional fat distribution with blood pressure investigated by 24-hour ambulatory blood pressure monitoring in android-type obese.

In 46 female outpatients with android-type obesity, body mass index (BMI) 36.6 +/- 1.0, waist to hip ratio (WHR) > 0.86, and normal glucose tolerance (NGT) who were hypertensive at entry study [blood pressure (BP) > 140/90 mm Hg] and in 10 clinically healthy, nonobese, normotensive women, we evaluated the relationship between BMI, fat mass, WHR, fasting blood glucose, sum of blood glucose levels during oral glucose tolerance test and casual BP levels, 24-h ambulatory BP monitoring (ABP) parameters as the 24-hour mean, day-time mean, night-time mean and, by using a periodic model of cosine regression, MESOR (midline estimating statistic of rhythm), amplitude, acrophase, and baric impact. In android obese women, a negative correlation between ABP levels (day-/night-time, MESOR, and baric impact of systolic BP; night-time and MESOR of diastolic BP) and BMI has been documented. A positive correlation between systolic BP (casual, night-time mean, MESOR, amplitude, and baric impact), diastolic baric impact, and the WHR has been found. No correlation has been demonstrated between ABP monitoring parameters, and BMI, body fat, and WHR in the control group. Our data could suggest that, when enrolling obese subjects, it must be taken into account that obesity is a heterogeneous disorder. There are in fact obese subjects with normal or impaired glucose tolerance, as well as diabetics with moderate to severe obesity and with gynecoid or android-type obesity. In our android obese subjects with NGT, the WHR rather than the BMI was found to be a better predictor of hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1995

Early detection by non-invasive monitoring of abnormally elevated systolic blood pressure in newborns with a positive familiarity for hypertension.

This study investigates 263 full-term clinically healthy newborn babies: subdivided into two groups depending on a positive (113 individuals) or negative (150 subjects) family history for hypertension. The babies were comparable for body weight and statural height and equipartitioned into males and females. The infants underwent a non-invasive, automated monitoring of blood pressure during the first three days of their life, according to protocol in which the systolic and diastolic measurements were performed at 1 min intervals over 15 minutes. The babies of the two groups showed superimposable mean values for systolic and diastolic blood pressure. However, the neonates with a positive familiarity for hypertension showed a higher number of systolic readings above the reference limit of 90 mmHg. The higher incidence of the abnormally-elevated systolic values (> 13%) in babies with a positive familiarity for hypertension was seen to be significant, suggesting that their blood pressure pattern is characterized by a larger variability at least in the systolic component. Such a wider variability may be regarded as a phenotypic expression of the genetic predisposition to hypertension, whose risk can be detected by a short-term monitoring of BP soon after the birth.

Age Factors↗

PubMed1994

Histological study of pancreatic beta-cell loss in relation to the insulitis process in the non-obese diabetic mouse.

Non-obese diabetic (NOD) mice spontaneously develop an autoimmune diabetes with higher incidence in females than in males. In order to elucidate possible factors involved in the different incidence of diabetes between male and female mice, we studied the progression of pancreatic beta-cell loss in relation to mononuclear cell infiltration of the pancreas (insulitis). We examined the pancreas of 76 NOD mice (39 males and 37 females) of different ages. The beta-cell content was assessed by immunoperoxidase staining of sections with an anti-insulin serum and the severity of insulitis was determined by haematoxylin staining of the same sections. A semi-quantitative criterion was used to grade both parameters. The results showed that females have a faster loss of beta-cell mass, which progressively decreases with the increase of severity of insulitis. In males, a medium to severe degree of insulitis is required before initial loss of beta cells occurs. Under the age of 10 weeks there was a significantly lower content of beta cells in females than males (2.84 +/- 0.03 vs 2.67 +/- 0.07; P = 0.02). Since we never observed a significant difference in the degree of mononuclear cell infiltration in age-matched males and females, these data support the hypothesis of weaker beta-cell resistance to immunological attack in female mice. Thus beta-cell sensitivity, in addition to immunological activity, is an important factor in the pathogenesis of insulin dependent diabetes.

Aging↗

PubMed1994

Campodimele study: blood pressure and heart rate pattern in clinically healthy elderly subjects.

Noninvasive ambulatory blood pressure (BP) monitoring is a developing method in clinical practice. Its interpretation needs reference standards stratified by age and gender. This study addresses ambulatory BP monitoring in elderly people with the purpose of quantifying the discrete and periodic variability of BP pattern over a 24-h period. The ABPM was performed in 92 clinically healthy subjects (45 men and 47 women) ranging in age from 76 to 102 years. The results refer to the time-qualified mean values with their dispersion, to the circadian rhythm with its parameters, and to the daily baric impact (BI) with its variability. The conclusion is drawn that BP preserves its nychtohemeral variability and circadian rhythmicity despite old age. The daily BP mean level and BI in older people in good health are comparable with those of young subjects, suggesting that humans surviving into old age are characterized by a eugenic control of their pressure regimen.

Aged↗

PubMed1994

Influence of reapportionment of daily salt intake on circadian blood pressure pattern in normotensive subjects.

The aim of this study was to investigate whether there is variation in blood pressure when we reapportion the percentage of total daily salt intake consumed at each of three regular meals. The study was conducted on seven clinically healthy normotensive female subjects who, in Stages LH and DH, consumed two-thirds of the normal daily salt intake (12 g/day) at lunchtime or at dinnertime, respectively. The total daily amounts of nutrients and dietary salt were similar in Stage-R (regulated salt intake), Stage-LH (a high-salt intake at lunchtime), and Stage-DH (a high-salt intake at dinnertime). The blood pressure response to the variation of sodium content in the meals was examined by means of noninvasive automated blood pressure monitoring (ABPM-630; readings every 15 or 30 min over 48 h) and chronobiologic analysis. A significant shift of blood pressure circadian rhythm was observed in Stage-LH. Additionally, the 24-h mean level of blood pressure significantly increased when the prevailing salt intake was at lunch, and significantly decreased when the prevailing intake was at dinner. These opposite responses corroborate the view that the blood pressure susceptibility of human beings to salt intake varies during the day, showing its maximal expression at midday. Such a time-dependent sensitivity may be exploited for better nutritional prevention and treatment of arterial hypertension by reapportioning the salt intake so that two-thirds is consumed at dinner.

Adult↗

PubMed1994

[Chronobiological standards of 24-hour arterial blood pressure validated by bayesian criteria].

The monodiagnosis of hypertension via ambulatory (A) blood pressure (BP) monitoring (M) is erroneous by definition. Its use has to be substituted by the chronodiagnosis. Because of the lack of an international standardization, the BP chronobiologic reference limits have to be computed on a small sample size. For this compilation, it is, however, unavoidable the recruitment of normotensive subjects using the WHO's fixed limits. These chronobiologic standards are by principle contaminated by false negatives and need a bayesian validation. Such a depuration has been made by reclassifying each subject using the BP time-qualified standards. A secondary sample was constituted on the true normotensive reclassified. This sample provided the a posteriori reference standards for BP. The bayesian chronobiologic reference standards seem to be the limits with which the chronodiagnosis of hypertension can be suitably done via ABPM.

Adult↗

PubMed1993

Blood pressure 24-hour pattern in two industrialized countries (Italy and Japan) with a different culture in salt intake.

This study investigates the blood pressure (BP) 24-hour pattern in representative samples of 2 industrialized countries, Italy and Japan, showing different cultures in salt intake. BP was monitored by means of a noninvasive ambulatory device whose readings were analyzed by means of chronobiometric procedures. The results show that the 24-hour BP pattern is not substantially different in Italian and Japanese subjects. In particular, the expected lower BP in the Italians was not detected despite their lower salt intake. Because the 24-hour mean BP value was seen not to be proportional to salt intake, the hypothesis is formulated that maintenance of the pressure regimen within a given range of variability is a principle of human physiology. To comply with this rule the Japanese people are supposed to have ethnically developed a certain resistance to dietary salt for which their cardiovascular apparatus is protected (phyletic escape to dietary sodium excess).

Adult↗

PubMed1993

Twenty-four-hour pattern of atrial natriuretic peptide in heart transplantation: evidence for lack of circadian rhythm. Temporal inter-relationships with plasma renin activity, aldosterone and cortisol.

We have investigated the circadian rhythm of plasma atrial natriuretic peptide in 13 stable output heart transplanted patients, all without evidence of histological rejection and cardiac impairment, following antirejection therapy with Cyclosporine, Azathioprine and Prednisone. The 24-h pattern of plasma renin activity, plasma aldosterone and plasma cortisol has been studied as well. All the investigated variables were assayed six times over the 24-h span. The circadian time-qualified data were analyzed by ANOVA and Cosinor method. The 24-h mean levels of atrial natriuretic peptide, plasma renin activity and plasma aldosterone are significantly increased, while the concentrations of plasma cortisol are reduced in the heart transplanted recipients. ANOVA detected a significant within-day variability of all these humoral variables only in healthy subjects. A statistically significant circadian rhythm was validated by Cosinor procedure for all the investigated molecules in healthy subjects but not in heart transplanted patients. In our opinion, the increase of atrial natriuretic peptide is a counterregulatory mechanism aimed to compensate the cyclosporine-mediated activation of the renin-angiotensin-aldosterone system. The disappearance of the plasma renin activity, aldosterone and atrial natriuretic peptide circadian rhythm can be ascribed to the constant activation of the renin-angiotensin-aldosterone system. The hypocortisolism is due, in our opinion, both to glucocorticoid therapy and increase of plasma ANP concentration.

Adult↗

PubMed1993

A chronobiological approach to circulating levels of renin, angiotensin-converting enzyme, aldosterone, ACTH, and cortisol in Addison's disease.

This study deals with a chronobiological approach to the circadian rhythm of the renin-angiotensin-aldosterone system (RAAS) and the ACTH-cortisol axis (ACA) in patients with Addison's disease (PAD). The aim is to explore the mechanism(s) for which the circadian rhythmicity of the RAAS and ACA takes place. The study has shown that both the RAAS and ACA are devoid of a circadian rhythm in PAD. The lack of rhythmicity for renin and ACTH provides indirect evidence that their rhythmic secretion is in some way related to the circadian oscillation of aldosterone and cortisol. This implies a new concept: a positive feedback may be included among the mechanisms which chronoregulate the RAAS and ACA.

Addison Disease↗