Biomedical subjects

S Sensi

Publications and source records attributed to S Sensi.

At least 19 recordsLinked to original sources

PubMed2001

Large waist circumference and risk of hypertension.

OBJECTIVE: To examine the relationship between 24 h ambulatory blood pressure monitoring and three commonest anthropometric measurements for obesity--body mass index (BMI), waist-to-hip ratio (WHR) and waist circumference (W). DESIGN: Cross-sectional survey among outpatients at the Obesity Research Center. SUBJECTS AND METHODS: Four-hundred and sixty-one overweight or obese subjects, non-diabetic, otherwise healthy, aged 20-70 y, of either sex, were consecutively recruited. All subjects underwent 24 h ambulatory blood pressure monitoring. The population study was separated in normotensive and hypertensive males and females and the possible risk factors for hypertension (W, WHR, BMI and age) were subdivided into different classes of values. RESULTS: Logistic regression shows that W is the most important anthropometric factor associated with the hypertensive risk. Among males with W> or =102 cm the odds ratio (OR) for hypertension is three times that of males with W<94 cm using casual BP measure (OR 3.04), nearly four times higher using 24 h BP mean (OR 3.97), and even five times higher using day-time BP mean (OR 5.19). Females with W> or =88 cm have a risk for hypertension twice that of females with W<80 cm, whatever BP measurement was take (casual, 24 h or day-time). Males with WHR> or =0.96 and females with WHR> or =0.86 show significant OR for hypertension only by 24 h BP measurement and by day-time BP measurement. BMI seems to have no significant relationship to hypertensive risk. Age shows a significant relationship to hypertensive risk only considering males aged > or =55 y and females aged > or =50 y. CONCLUSION: The waist circumference seems to have a strong association with the risk of hypertension, principally by the ambulatory BP monitoring, when compared with casual BP measurement.

Adipose Tissue↗

PubMed2001

[Professional licensing examination. Innovative experience: the Integrated Multimedia Pilot Project of the Chieti University].

The Medical Licensing Examination (MLE) is governed, in Italy, by a law enacted in 1956. An ideal clinical competence assessment tool should effectively, reliably and objectively measure all the components of clinical competence: basic knowledge and clinical skills as history-taking, performing a physical examination, formulating the most likely diagnosis, establishing a management plan, communication and interpersonal relations. Since 1998 first session of the MLE, Chieti University implemented computer-based case simulations and standardized patients in the Multimedia Integrated Pilot Project (MIPP) administration. At the present time, we have examined 370 subjects during five sessions of MLE. This preliminary work shows results regarding the examinees in the first examination session of 1998 and 1999. The two groups of examinees are relatively homogeneous for number, age, gender, length of curriculum and country of University degree. In both groups the curriculum scores (preclinical, clinical and total) and the MIPP final score are reported for all subjects, first ten and last ten examinees. The MIPP final score is moderately correlated with the preclinical, clinical and total curriculum scores. Recently, the Federation of State Medical Boards and the National Board of Medical Examiners, sponsoring organisations of the United States Medical Licensing Examination (USMLE), have been planning the implementation of computer-based testing for the USMLE. It is important to point out that our MIPP-based MLE is not a mere didactic experiment, but a legal certifying examination valid for licensure.

Adult↗

PubMed2001

Clinical nutrition: inadequate teaching in medical schools.

BACKGROUND AND AIM: The teaching of Clinical Nutrition (CN) is frequently neglected in Medical Schools, though many official institutions strongly recommend its incorporation in their curricula. This work aimed to assess CN knowledge among final-year medical students and final-year dietology diploma students. METHODS AND RESULTS: We compared the performances of final-year Medical School students who did and who did not take the CN course and final-year dietology students in a computer-based multiple choice question examination related to core CN competencies that primary-care physicians and dieticians should know and be able to put into practice. The medical students who did not take the CN course correctly answered significantly fewer questions compared with those who did and the dietology students (both p < 0.001). There was also a difference in the percentages of who passed the test: students who did not take the course: those 18%; those who did: 77%; dietology students: 76% (p < 0.001). CONCLUSIONS: There are numerous barriers to the incorporation of nutrition in Medical School curricula. The medical school students may have achieved poorer results because dietology students followed nutrition education programs later in their curriculum. Our Medical School has therefore included CN education as part of its internal medicine course since 1998.

Adult↗

PubMed2000

Risk factors for hypertension in obese women. The role of weight cycling.

OBJECTIVE: To study significant factors associated with the risk of hypertension among obese women, with and without a history of weight cycling (WC). DESIGN: Case-control study. SETTING: Obesity Clinic of Chieti University, Italy. SUBJECTS: A group of 258 obese women aged 25-64 y (103 cases with hypertension and 155 controls) were recruited. All obese subjects had the same clinical characteristics, were without a family history for hypertension, were non-smokers, had normal lipidemic profiles and normal glucose tolerance, were not taking any medication and were otherwise healthy. INTERVENTION: In the weight cycling women, the history of WC was established on the basis of at least five weight losses in the previous 5 y due to dieting, with a weight loss of at least 4.5 kg per cycle. A logistic regression model adjusted for confounding variables such as waist-to-hip ratio (WHR) and weight cycling history parameters was used and the odds ratio (OR) with 95% confidence intervals was calculated. RESULTS: The risk of hypertension increases in subjects with larger WHR (OR 7.8; 95% CI 3.4-17.9) and with a positive history for WC (OR 4.1; 95% CI 2.4-6.9). Further, in obese patients with WC, the weight cycling index and the sum of the weight regained are also important risk factors for hypertension. CONCLUSIONS: These findings could support the hypothesis that it is the combined exposure of central-type obesity and WC that strongly raises the risk of hypertension. SPONSORSHIP: This work has been financially supported by a grant of Ministero dell'Università e della Ricerca Scientifica e Tecnologica.

Adult↗

PubMed2000

Does holiday hypoglycaemia exist?

BACKGROUND: To determine whether an excessive, prolonged and, above all, unusual physical exertion could be associated with episodes of mild hypoglycaemia in non-insulin-dependent diabetes mellitus (NIDDM) patients treated with glibenclamide. METHODS EXPERIMENTAL DESIGN: 11 months of observation with retrospective analysis of patient personal diaries to determine the hypoglycaemic risk. SETTING: Diabetic Unit-Department of Medicine and Aging-Chieti University School of Medicine. PATIENTS: We enrolled 340 NIDDM outpatients adjusted for sex, age, body mass index, alcohol intake and oral treatment regimen with glibenclamide. PATIENTS were tested monthly for circadian blood glucose profiles and glycosylated hemoglobin. Mild hypoglycaemia was defined on the basis of blood glucose values < 2.8 mmol/l associated with mild autonomic symptoms, without requiring external assistance. Each diabetic patient filled personal diary indicating the therapy regimen and the characteristics of eventual hypoglycaemic episodes occurring during the observation period. RESULTS: 21.8% of NIDDM patients experienced one or two episodes of mild hypoglycaemia during the observation period. The analysis of the patients' diaries showed that 60% of the hypoglycaemic episodes was associated with excessive, prolonged and unexpected physical exertions. Within this group, about 70% of the episodes occurred during a holiday ("holiday hypoglycaemia"). After analyzing the socio-demographic and clinical characteristics of the diabetic patients reporting hypoglycaemic events, we found a higher risk for "holiday hypoglycaemia" in patients with a lower educational level, with a sedentary occupation or among the ex-farmers. CONCLUSIONS: As resulted in the present study, unexpected physical exertions may represent a relevant cause of mild hypoglycaemia in diabetic patients receiving oral antidiabetic therapy. However, this hypoglycaemic cause may have been underestimated in the literature. Educational programs conducted by general practitioners or diabetologists could be useful for the patients in reducing the number of mild hypoglycaemic episodes.

Diabetes Mellitus, Type 2↗

PubMed1999

Weight fluctuations could increase blood pressure in android obese women.

Recent studies have documented a relationship between increased morbidity and mortality from cardiovascular diseases and a history of weight cycling (WC) in obese subjects. We performed a cross-sectional analysis in 96 weight-cycling android obese women, matched with 96 non-weight-cycling android obese women by age, body mass index (BMI) and waist-to-hip ratio (WHR), to evaluate any increase in blood pressure (BP) levels in association with WC. The patients were all between 20 and 45 years old, were non-menopausal, did not smoke, did not take any medication, had normal glucose tolerance and were otherwise healthy. A history of WC was established on the basis of at least five weight losses in the previous 5 years due to dieting, with a weight loss of at least 4.5 kg per cycle. We documented higher levels of casual BP in the weight-cycling obese compared with the non-weight-cycling subjects: 147+/-12/90+/-8 mmHg versus 125+/-14/79+/-8 mmHg (P<0.001). The women with WC showed a statistically significant positive correlation between BP and age, weight, BMI, waist circumference, WHR, total weight regained and weight cycling index (WCI). However, in a multiple regression model only the WHR and WCI contributed significantly to the BP variability. These findings could support the hypothesis that it is the combined exposure of central-type obesity and WC that strongly raises the prediction of hypertension.

Adult↗

PubMed1998

Effect of thyroid function on LDL oxidation.

In this study, the effect of different levels of thyroid hormone and metabolic activity on low density lipoprotein (LDL) oxidation was investigated. Thus, in 16 patients with hyperthyroidism, 16 with hypothyroidism, and 16 age- and sex-matched healthy normolipidemic control subjects, the native LDL content in lipid peroxides, vitamin E, beta-carotene, and lycopene, as well as the susceptibility of these particles to undergo lipid peroxidation, was assessed. Hyperthyroidism was associated with significantly higher lipid peroxidation, as characterized by a higher native LDL content in lipid peroxides, a lower lag phase, and a higher oxidation rate than in the other two groups. This elevated lipid peroxidation was associated with a lower LDL antioxidant concentration. Interestingly, hypothyroid patients showed an intermediate behavior. In fact, in hypothyroidism, LDL oxidation was significantly lower than in hyperthyroidism but higher than in the control group. Hypothyroidism was also characterized by the highest beta-carotene LDL content, whereas vitamin E was significantly lower than in control subjects. In hyperthyroidism but not in the other two groups, LDL oxidation was strongly influenced by free thyroxine blood content. In fact in this group, the native LDL lipid peroxide content and the lag phase were directly and indirectly, respectively, related to free thyroxine blood levels. On the contrary, in hypothyroidism LDL oxidation was strongly and significantly related to serum lipids. In conclusion, both hypothyroidism and hyperthyroidism are characterized by higher levels of LDL oxidation when compared with normolipidemic control subjects. In hyperthyroid patients, the increased lipid peroxidation was strictly related to free thyroxine levels, whereas in hypothyroidism it was strongly influenced by serum lipids.

Antioxidants↗

PubMed1998

Many factors can affect the prevalence of hypertension in obese patients: role of cuff size and type of obesity.

OBJECTIVE: To determine to what extent methodological errors, including measurements taken with inappropriate cuffs and/or inaccuracies in patient enrollment, can contribute to overestimating the prevalence of hypertension in overweight or obese women. EXPERIMENTAL DESIGN: Randomized and comparative investigation in overweight or obese outpatient women of the Obesity Clinic, Internal Medicine Institute, Chieti University. PATIENTS: In 1,791 overweight or obese women, randomly selected and stratified by age (41-60 years), blood pressure (BP) was taken with casual measurement in the morning. The entire study group was divided into two subgroups. In the first one, causal BP was measured with a standard-size cuff (RCS), while an appropriate large-size cuff was used for the second one (LCS). Patients of the latter subgroup were also divided by type of obesity (android and gynoid), based on their waist-to-hip ratio. RESULTS: In the LCS subgroup, the hypertension prevalence rate was strikingly lower among overweight and obese women, as well as in the younger and older age groups, when compared with the corresponding RCS subgroups (p < 0.001). The hypertension prevalence rate was higher for all android obese subjects (53%), including younger (34%) and older (64%) groups, when compared with gynoid obese patients (29%, 18% and 42%, respectively). CONCLUSIONS: A comparison of different reports on the prevalence of hypertension in obesity reveals considerable differences, due mainly to age, sex, race and income level. Nevertheless, our data seem to indicate that even after adjusting for the above-mentioned variables, two significant confounding factors, cuff hypertension and the prevalence of android obesity in the obese study population, could be responsible for over-estimating the prevalence of hypertension. It should be noted that for certain groups of overweight and obese women, the prevalence of hypertension becomes similar to the rate found among the general population, as reported in many large epidemiological surveys.

Adult↗

PubMed1998

[Assessment of clinical competence of medical school graduates in Italy with standardized patients. The opinion of the examinees].

An international collaborative project for the evaluation of clinical competence at the end of the Medical School curriculum using the ECFMG-CSA (Educational Commission for Foreign Medical Graduates--Clinical Skills Assessment) prototype was started in Italy in April 1996. Faculty representatives from Italian Medical Schools and experts from the ECFMG in Philadelphia participated in the Project. The CSA consists of integrated clinical encounters with 10 standardized patients during which the examinee is asked to obtain a focused history, perform a relevant physical examination and communicate initial diagnoses and management plan to the Standardized Patient (SP). The SP then completes checklists that are scored by Faculty members. The project was concluded in Spring 1998 and a total of 173 new graduates were examined. The data elaborated by the primary site in Chieti University will be available in the Fall 1998 by the ECFMG in Philadelphia. This preliminary communication reports the opinions of the examinees on the ECFMG-CSA, contained in the questionnaires administered after the test. Most of the examinees considered this new methodology as a valid tool for the assessment of clinical competence, especially history-taking and interpersonal skills and stated that the SP simulations were realistic. The 72% of examinees indicated that the Medical School curriculum does not adequately prepare for the CSA examination. Lastly, 68% was in favour of including the SP in the Medical Licensing Examination.

Clinical Competence↗

PubMed1998

A new model to assess tcpO2 changes during heat-dependent vasodilation: preliminary observations.

The transcutaneous pO2 (tcpO2) changes induced by the increase of temperature to 45 degrees C after electrode stabilization at 37 degrees C were continuously recorded. The mathematical analysis of the curve led us to identify three different parameters: the half-slope "b" time, the angular "mT" coefficient and the angular "mb" parameter, which are not simply the expression of the maximum vasodilation capacity but mainly of the dynamic response of the microcirculatory system to skin heating. These parameters derived from the computerized mathematical analysis of the curve can be also obtained by a graphical approach with a very good approximation. The angular "mb" coefficient was shown to possess the highest statistical power in discriminating the POAD patients from normal controls. The clinical relevance and the possible pathophysiological meaning of these preliminary observations have to be confirmed.

Ankle↗

PubMed1997

Transdermal clonidine therapy and blood pressure nocturnal fall in mild hypertensive male subjects.

UNLABELLED: Treatment of mild hypertension with an antihypertensive drug administered by means of a transdermal therapeutic system (TTS) could produce favorable results, when compared with a traditional oral regimen. PURPOSE: Using 24-h ambulatory blood pressure (BP) monitoring (ABPM) in mild hypertensive male subjects, to analyze three aspects which have not been completely clarified: a) whether a latency in the antihypertensive effect may be present, recording BP already from the first day of application of the patch, b) the eventual hazardous enhancement of circadian nocturnal fall in BP values in treated mild hypertensive patients and, c) the possible overlapping of antihypertensive effect between the administration of two consecutive patches. SUBJECTS AND METHODS: In 12 caucasian male outpatients (yrs 55 +/- 3 SEM) with uncomplicated essential mild hypertension, a patch containing placebo was applied for the first week (T 0 period). At the end of the T 0 period, a 5 mg TTS-2 clonidine patch was applied for one week, and, subsequently, a new patch of 5 mg TTS-2 clonidine was kept for another week. ABPM was performed on the last day of the placebo period (T 0) and on the 1st day (T1), the 7th day (T2) and the 14th day (T3) of transdermal clonidine therapy. RESULTS: Both systolic and diastolic BP (24 h mean, day-night-time) decreased on the 1st, 7th and 14th day, when compared with T0. However, no significant differences were documented between the BP levels on the 1st and the 7th day of treatment. The incidence of nocturnal fall in systolic and diastolic BP was evaluated and no significant differences were found, when compared with night-time reference values. CONCLUSIONS: When compared with the placebo period, TTS-2 clonidine lowers SBP and DBP within the first 24 hours of application. The antihypertensive effect persists at the end of the first week, as well as after 14 days. The lowest values of systolic-diastolic BP documented were not below the levels reported in normotensive men. Therefore, TTS-2 clonidine seems to act as an antihypertensive agent rather than a hypotensive drug since it normalizes BP without lowering it below physiological levels.

Administration, Cutaneous↗

PubMed1996

Assessment of clinical competence. The state of the art.

Clinical competence (CC) can be defined as the professional skills required to act and represents the fundamental background required for the performance. From a taxonomic standpoint, CC regards the field of knowledges, gestures, behaviours and decision-making skills in patient management on the basis of a cost-benefit analysis. "Methods for the assessment of CC". Since the 50s, the National Board of Medical Examiners started to replace open-ended oral examinations with the "Multiple Choice Questions", which proved to be more objective, reliable and effective and were soon accepted worldwide. New educational tools were successively suggested as computer-aided simulation ("Computer Aided Instruction") for both learning and assessment phases. All the above mentioned methods are limited by the fact that they are unable to evaluate the field of gestures and behaviours of the future physician. In consideration of this limitation, new assessment tools as the "Standardized Patient" utilized in the context of "Objective Structured Clinical Examination" or "Simulated Clinical Encounter", were recently developed. There are still some problems regarding the elaboration of assessment standards able to provide uniformity in scoring. In addition the assessment tools utilized so far for the individual student do not provide predictivity on his/her outcome in the future medical practice. Nevertheless, there are still some perplexities on the use of a chart audit for the purpose of assessing individual competence and predicting future performance skill.

Clinical Competence↗

PubMed1996

The prevalence of hypertension in gynaecoid and android obese women.

Until now the different epidemiological studies performed have yielded widely different results in terms of the prevalence of hypertension in obese patients. This is mainly due to methodological errors in blood pressure (BP) measurements, including such false positives as white-coat or cuff hypertension, and more recently, to the different distribution in the study population of obese subjects at risk of hypertension (android obesity type). In 803 obese outpatient women (body mass index range: 28-45) randomly selected and subdivided into younger and older groups, and into android and gynaecoid, the casual BP was measured in the morning with a large size cuff. In addition, in 82 obese outpatients casual BP was measured simultaneously with the large and a standard size cuff. Another group of 94 patients was submitted to 24-h ambulatory blood pressure monitoring (ABPM). The aim was to observed if the use of inappropriate cuffs, or the incidence of white-coat hypertension and the prevalence of obese subjects at risk of hypertension, may contribute considerably to overestimating the prevalence of hypertension in obesity. The hypertension prevalence rate was 37.6% for the entire study group. The prevalence rate was 26.2% in women with gynaecoid type of obesity and 47.1% in android obese subjects. We could conclude that the use of inappropriate cuffs, office or white-coat hypertension and the prevalence of obese subjects at risk of hypertension, may contribute considerably to overestimating the prevalence of hypertension in obesity. The number of hypertensive subjects in younger obese subjects with gynaecoid fat distribution is similar to non-obese subjects who are age-adjusted, but our data confirm that the prevalence of hypertension in android type of obesity is significantly higher than in non-obese subjects.

Adult↗

PubMed1995

Increase in plasma levels of adenosine and adenine nucleotides after intravenous infusion of buflomedil in humans.

To clarify the mode of action of the vasoactive agent buflomedil, we evaluated plasma levels of adenosine and adenine nucleotides after intravenous (i.v.) infusion in humans of 50, 100, and 200 mg of the drug in 20 min. Buflomedil induced an increase of the same order of magnitude in plasma levels of adenosine and adenine nucleotides. Maximal adenosine increase (84%) was observed at the end of the infusion period, whereas peak plasma levels of ATP and ADP (69 and 55%, respectively) and of AMP (61%) were detected 10 and 5 min after discontinuation of infusion, respectively. Although the exact mode of action of buflomedil at the molecular level remains unclear, some indirect findings suggest that the increase in adenosine may be due to enhanced release rather than to inhibition of cell uptake. Because such activity of buflomedil consists of enhancement of physiologic mechanisms of vasodilation and tissue protection occurring in the course of ischemic events, new pharmacologic perspectives for the drug may arise.

Adenine Nucleotides↗

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↗

PubMed1994

Ambulatory blood pressure monitoring in evaluating the relationship between obesity and blood pressure.

The relationship of body mass index, body fat, waist to hip ratio, fasting blood glucose and sum of blood glucose levels during oral glucose tolerance test with casual blood pressure (BP) and BP parameters obtained by 24h ambulatory BP monitoring in 97 out-patients moderately obese (66 with android type obesity), normal glucose tolerance and mild hypertension at entry study, has been evaluated. A negative correlation between body mass index and systolic ambulatory BP levels as the 24h mean, daytime and nighttime, has been documented in all of the obese subjects; no correlations between body mass index and casual BP were shown. Only in the group of android type obese was the body mass index correlated positively with the casual DBP. Systolic 24h and nighttime BP values correlated positively with waist to hip ratio; the correlation coefficients improved in the subgroup of android type obese. By using 24h ambulatory BP monitoring, it may be possible to show that waist to hip ratio is a better predictor of systolic hypertension than other parameters such as those derived from weight and height measurements and body fat percentage.

Adipose Tissue↗

PubMed1994

[Teaching merit should be valued? Reflections and proposals].

UNLABELLED: Can intellectual performance be evaluated qualitatively and quantitatively, and can it be useful to evaluate competence and pedagogic capacity? Experts and laws attempted to answer these questions in the last years. A recent law establishes that the Board of examiners should formulate the evaluation criteria of maximum before the examination of titles to proceed with a fair evaluation of didactic and scientific titles of the candidates. A clear and unequivocal position on the importance of teaching in Medical Schools comes from the Consensus Conference of the World Federation for Medical Education in 1988 and more recently from the World Summit on Medical Education (1993). Proposals: a task-force has recently been constituted with the following objectives: identify of evaluation criteria on teaching competence and formulate strategies of co-optation. Action: teaching and pedagogic capacities should be evaluated in a quantitative and qualitative manner. The Faculty and/or other institutional organisms could certify teaching activity within the Faculty (quantitative indicators) through the "credit system" and the quality of teaching could be evaluated by the students and/or by institutional organisms. CONCLUSIONS: The evaluation of teaching competence in equally important as the evaluation of biomedical research.

Education, Medical↗

PubMed1993

Chronobiology in endocrinology.

Temporal endocrine structure (TES). It can be defined as a combination of predictable hormonal changes that are time-related. Regarding their frequency, endocrine rhythms may be circadian, ultradian and infradian. In this context, the endocrine circadian time structure (ECTS), that is closely dependent of some areas of the hypothalamus, is of particular interest. Long and short loop feedback link together the various components: central nervous system (CNS), hypothalamus and anterior pituitary with target glands and tissues. The hypothalamic neuropeptides (releasing hormones or factors - RH or RF - or inhibiting hormones or factors IH or IF) presently known are: thyrotropin releasing hormone (TRH); luteinizing releasing hormone (LH RH); prolactin releasing factor (PRF); Prolactin Inhibiting Factor (PIF); Corticotropin Releasing Factor (CRF); Growth Releasing hormone (GH RH). Some general remarks on endocrine rhythms should be noted: the circadian changes in hormones may depend on each other; even an apparently subordinate rhythm should be considered a true independent rhythm; accurate studies have shown that hormonal secretion occurs in all cases according to a rhythmic organization at many levels; these rhythms may not be evident at a first analysis. The hormone secretion is basically pulsating which makes it difficult to draw standard reference values. Although an ECTS is present at the cell level, in organs etc., it is evident that a rhythm hierarchy exists. Hormonal secretion and sleep-wake cycle. Although several reports state that no rhythm is totally dependent on the sleep-wake cycle, from a general point of view the hormone secretion rhythms can be divided in: sleep-dependent rhythms and sleep-independent rhythms. Meal-timing and hormonal secretion. In animals, meal-timing is a powerful synchronizer; however, there are no definitive and conclusive data to prove that meal-timing is a true synchronizer also in humans, although there have been some reports suggesting it. Endocrine rhythms. Data regarding the endocrine rhythms (circadian-ultradian-infradian) of the numerous hormones as GH; prolactin; aspects of temporal pattern of CRF-ACTH-corticosteroid and of hypothalamic - pituitary - thyroids axis; hypothalamic - pituitary - ovaric steroid and testosterone axis are reported. The study of a possible rhythmic pattern of insulin has been approached from many points of view as the basal rhythmicity of insulin; the diurnal variation of efficacy of injected insulin and of insulin responsiveness to insulinogenic stimuli.

Chronobiology Phenomena↗