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Biomedical subjects

B Tarquini

Publications and source records attributed to B Tarquini.

At least 91 records · Page 5Linked to original sources
PubMedDate not supplied

[Circadian changes in serum prolactin in a group of apparently healthy subjects].

Serum immunoreactive prolactin was evaluated in 16 female and 5 male apparently healthy subjects aged 21-76 yr. After a period of synchronisation, with sleep from 22 to 5 and standardized meals at 8-8.30, 12-12.30, 17.30-18, venous blood samples were taken at 4, 8, 12, 16, 20 and 24. The radioimmunological data were processed using an ordinary chronogram technique and quantified by mean cosinor method. A significant (p less than 0.05) circadian rhythm was noted, with an acrophase at 1.45, amplitude of 2.17 and Mesor 6.89. Chronobiological studies are thus needed to determine the best normal temporal values of prolactin when setting control standards in pathological situations.

Adult↗
PubMedDate not supplied

Circadian rhythm in prostatic acid phosphatase (PAP): a potential tumor marker rhythm in prostatic cancer (PCa).

In order to define circadian states for an earlier diagnosis and for optimal response to treatment, the possibility of a circadian rhythm in serum PAP was investigated in subjects with and without prostatic cancer. Two groups of subjects were investigated: a. 12 patients affected by PCa, further subdivided in two subgroups: 1. without metastasis (6 patients) and 2. with metastatic disease (6 patients); b. 9 age-matched healthy control subjects. Controls and PCa patients were synchronized before starting the study with standardized meal times and nocturnal rest (22(00) to 06(00) ). Venous blood samples were drawn at prearranged hours (00(00), 04(00), 08(00), 12(00), 16(00), 20(00) ) for 24 consecutive hours. Each serum sample was assayed for PAP. Data on each group and subgroup were evaluated by conventional statistical analysis and by 'single' and 'population mean cosinor' to define rhythm parameters. PCa patients, as a single group, did not show a significant circadian PAP rhythm. A statistically significant circadian PAP rhythm was however detected in the subgroup without metastasis, on the contrary no rhythm was detected in the subgroup with metastatic disease. The potential of these rhythms as marker of cancer is noted.

Acid Phosphatase↗
PubMedDate not supplied

Pepsinogen gastrin mesor ratio: a potential simple marker for gastric secretory function.

As compared to control subjects, patients with duodenal ulcer show decreased levels of serum G and increased levels of serum Group I pepsinogen (PGI). On the other hand, pregnant women in their third trimester show an increased level of serum G and decreased levels of serum PGI. Gastrin stimulates gastric secretion and has a trophic effect on the parietal cells. Concentrations of PGI in serum reflect the capacity of pepsin-secreting cells which are, in turn, closely related to the parietal cell mass. Pepsinogen/G ratio (PGI/G) could represent the effective acid-peptic secretory capacity. This study suggests that for screening and clinical purposes PGI/G ratio provides a good potentially discriminatory marker of gastric secreting capacity reliably correlating and improving the diagnostic significance of single G and/or PGI serum levels.

Adolescent↗
PubMedDate not supplied

Timing of medical diagnosis and treatment: clino-circadian quantification of suppression by dexamethasone of the adrenal cortical cycle in healthy men.

The inhibitory effect exerted upon the cyclic activity of the adrenal cortex by a synthetic steroid analog (dexamethasone-21-phosphate) administered at different circadian stages, has been studied previously. Reexamination of the same data by microscopic methods herein provides two sets of objective quantitative endpoints for further studies, namely 1. the characteristics of a rhythm isolated from a superimposed trend as well as noise, and 2. the endpoints of the trend itself. These endpoints quantify the effect of dose and, with the appropriate dose, the optimal timing for a given purpose may also be found.

Adrenal Cortex↗
PubMedDate not supplied

The maternal 24-h blood pressure (BP) profile as a predictor of fetal distress.

No mention is made of any aspect of BP bioperiodicity, among current clinical criteria for diagnosing pregnancy-related hypertension. The abnormal BP, based on a single unqualified measurement, is accepted and utilized as a clinical feature to identify pregnancy at risk. Systolic, diastolic and mean arterial blood pressure were measured every 15 min for 24 h in 5 women (2 non pregnant clinically healthy subjects, 1 clinically healthy subject in her third trimester of pregnancy, 1 presenting mild and 1 severe toxiemia, also in their third trimester of pregnancy) by an automated BP recording apparatus (Dynamap). All variables, analyzed by the single cosinor method, exhibited statistically significant circadian rhythms. A high amplitude could nullify the time-unqualified usual range. The change in circadian amplitude precedes an overt mesor hypertension and constitutes a tool for earlier detection of fetal distress.

Adult↗
PubMedDate not supplied

Toward a medical prolepsis by chronobiology.

Medicine today strongly aims at prevention and optimization of diagnosis and therapy Studies tried staging and standardization of clinical trials in diseases and made search of markers for early diagnosis, prognosis and therapy. Moreover, risk factors and other variables such as predictors are now investigated more often in groups or populations of apparently healthy subjects, especially for such diseases as atherosclerosis and neoplasia. This new aspect of increasing interest may be defined as medical prolepsis (from the Greek pi rho ómicron lambda eta psi iota zeta = anticipated idea). It includes early signals of disease (protopathology) as well as other signals the host shows as defence or alarm reaction. Hence, we suggest a chronobiological approach in this field, which allows to quantify health and reveals more subtle differences in many physiological variables. According to these views, we reported studies concerning humoral markers and other parameters considered as risk factors both in atherosclerosis and in some endocrine tumors.

Arteriosclerosis↗
PubMedDate not supplied

An attempt to establish early signals of peripheral arterial disease (PAD): the use of rhythm's parameters of peripheral blood flow (RF).

Rhythm parameters of peripheral arterial rest blood flow (RF) as a potential predictor of peripheral arterial disease (PAD) have been investigated. Three groups of subjects have been studied: a. six apparently healthy subjects; b. seven high risk (hypertension, diabetes, hypercholesterolaemia, hypertriglyceridaemia, erythrocytosis) subjects; c. four occlusive PAD selected patients with one 'pre-symptomatic' leg. RF has been measured by 'strain-gauge plethysmography' every min for 25 min, 4 times/day. Right fore-arm, right leg and left leg have been assessed. Data have been analyzed by 'single and population mean cosinor'. Significant circadian rhythms have been detected in apparently healthy subjects. Mesor and amplitude can differ according to single individual's area. Mesor is higher in upper limb. RF circadian rhythm parameters differ in subjects with various vascular risk load. Sometimes, PAD-symptomatic limb shows higher mesor than pre-symptomatic one, suggesting conditions of reactive post-ischemic hyperemia or a role of RF in PAD. Circadian dyschronia can be detected in PAD limbs but also in high risk subjects, perhaps an example of chronoprotopathology. These results suggest the possibility of a clinical use of RF rhythm parameters as predictors of vascular protopathology.

Adult↗
PubMedDate not supplied

Iron metabolism: clinical chronobiological aspects.

Some features of clinical chronobiology are suggested on the basis of studies on the function of time in relation to various parameters of iron metabolism and factors associated with iron metabolism. In particular, so-called normal values, loading tests and the administration of iron (Eryfer) and chelating agents are reviewed in chronobiological terms. Some changes in the rhythms of iron metabolism are also discussed.

Bilirubin↗
PubMedDate not supplied

Differences in some circadian patterns of cardiac arrhythmia, myocardial infarctions and other adverse vascular events.

BACKGROUND: Results from unpublished data on the incidence of adverse vascular events and from several published studies are reevaluated chronobiologically. METHODS AND RESULTS: Cosinor methods indicate 1. a circadian variation in the incidence of paroxysmal supraventricular tachycardia (PST), of broadly classified ventricular arrhythmia (VAr), and of atrial fibrillation (AF); 2. a statistically significant difference in the timing of the circadian rhythm of PST and VAr versus that of AF; and 3. a further difference in the timing of these rhythms from that in the incidence of myocardial infarctions (MI). Electrocardiographic records for spans longer than 24h show the extent of day-to-day variability in circadian characteristics of the given patient and indicate the presence of even lower-frequency components, notably along the scale of a week, that may underlie weekly and half-weekly patterns of morbidity and mortality. CONCLUSION: Beyond alterations in the about 1-Hz periodicity of the heart, predictable changes along the scales of the day and the week may constitute a clue to the etiopathology of a given condition and provide a basis for treatment timing. The assessment of unfavorable changes in the lower frequency components may provide a lead time long enough to prompt the institution of preventive, rather than curative, intervention.

Animals↗
PubMedDate not supplied

[Circadian variations of bilirubin in the blood].

A group of 12 presumably healthy subjects was standardized for 7 days with rest time extending from 22.00 to 05.00. Meals were scheduled at 08.00-08.30, 12.00-12.30, 17.30-18.00 and the amounts consumed were standardized and measured. Each subject was sampled at 4-hour intervals throughout one 24-hour period; this involved the measurement of body temperature, radial pulse, blood pressure. In addition a sample of blood was collected at each time point and subsequently total, direct and indirect bilirubin measurement was made on each sample of serum. All data were analized by macroscopic approach (chronograms) and by mean cosinor. A circadian rhythm is detected in total, direct and indirect serum bilirubin.

Adolescent↗
PubMedDate not supplied

Serum melatonin in multiple myeloma: natural brake or epiphenomenon?

Melatonin (MEL), the main hormone produced by the pineal gland, seems to exert antineoplastic activity both in vitro and in vivo. Moreover, several studies reported increased melatonin blood levels in cancer patients. Plasma melatonin concentrations were determined in 46 patients with multiple myeloma and in 31 age matched healthy subjects (57.8 +/- 6.9 versus 55.2 +/- 8.9 years). Venous blood was drawn between 7.30 and 9.30 a.m. and melatonin was assayed using a commercially available radioimmunoassay. The data were analysed by Student's t test and results reported as mean values +/- standard deviation. The patients with multiple myeloma showed significantly higher mean melatonin serum levels than healthy subjects (21.6 +/- 13.5 versus 12.1 +/- 4.8 pg/ml; p < 0.001). This behaviour could actually represent a phenomenon secondary to an altered endocrine-metabolic balance caused by an increased demand of the developing tumor. On the other hand, the increased melatonin secretion might be considered as a compensatory mechanism due to its antimitotic action and therefore as an effort to secrete substances capable of regulating neoplastic growth.

Adult↗
PubMedDate not supplied

Circadian study on serum gastrin in patients with duodenal ulcers and in a control group.

Two groups of subjects (one consisting of fourteen apparently healthy subjects, the other of fourteen patients with peptic ulcers) were kept for a least 7 days on the same living schedule (nocturnal sleep for 22(00) to 05(00) and meals standardized at 08(00)-08(30), 12(00)-12(30), 17(30)-18(00)). During 24 hors, samples of venous blood were obtained from each subject every 4 hours for the serum gastrin radioimmunoassay. The results were analyzed by mean cosinor method. The control group has a statistically significant circadian rhythm, while we were not able to detect a circadian rhythm in the patients with duodenal ulcers. The daily mean of serum gastrin levels appears to be significantly reduced in the ulcer group.

Adolescent↗
PubMedDate not supplied

Serum osteocalcin levels in postmenopausal obese women.

In epidemiology of osteoporosis, obesity is to be considered one of its protecting factors. However there are in the literature discordant opinions: some authors describe a protective effect of obesity on the trabecular bone, others on the cortical one, others no effects at all and others finally a positive influence on both the trabecular and the cortical bone. However, only few studies on obesity's impact on bone metabolism are available. Bone mineral density at forearm and serum osteocalcin levels, a specific and sensitive marker of bone turn-over, in a group of postmenopausal obese women with those of a nonobese control group were compared. Obese women showed higher densitometric measurements than nonobese, but only the values of the third distal site of forearm resulted higher in a significant way. Serum osteocalcin values were similar between the two groups but the obese women showed a greater dispersion of the values (8.15 +/- 4.96 ng/ml) compared to nonobese (8.35 +/- 1.63 ng/ml). This high variability suggests an heterogeneity of bone turn-over in obese subjects and could explain the discordant results of the literature.

Bone Density↗
PubMedDate not supplied

Vascular damage and not hypertension per se influences endothelin-1 plasma levels in patients with non insulin dependent diabetes mellitus.

Several reports indicate higher endothelin-1 (ET-1) levels in patients with non insulin dependent diabetes mellitus (NIDDM), although this finding has not been confirmed by other studies. The discrepancy may be partially explained by the frequent coexistence in NIDDM patients of other pathologies, such as essential hypertension, and by the presence of diabetic vascular complications or renal failure, able, per se, to increase ET-1 circulating levels. This study aimed to evaluate the influence of arterial hypertension and/or of diabetic angiopathy on ET-1 circulating levels in a group of NIDDM patients. We measured ET-1 plasma concentrations in three groups of subjects: a) 22 NIDDM patients with or without hypertension and with or without vascular complications; b) 11 hypertensive patients; c) 14 age-matched healthy volunteers. Plasma ET-1 concentrations were significantly higher in NIDDM patients with angiopathy (7.3 +/- 0.7 pg/ml, mean +/- Standard Error; p < 0.001) than diabetics without angiopathy (4.4 +/- 0.53 pg/ml), hypertensive patients (4.7 +/- 0.85 pg/ml) and healthy subjects (3.1 +/- 0.19 pg/ml). This report indicates that increased plasma ET-1 levels in NIDDM patients may be ascribed only to those with vascular compliances, while hypertension, per se, does not affect ET-1 plasma levels in these patients.

Aged↗
PubMedDate not supplied

Serum beta-endorphin increase after intravenous histamine treatment of chronic daily headache.

Histamine is able to induce spontaneous-like headache attacks in migraine and cluster headache subjects. Therefore, it has been considered as a possible agent in the pathogenesis of headache. Histamine desensitization is used for the treatment of cluster and other chronic headaches like migrains with interparoxysmal headache. However, it is unknown whether desensitization plays a role in headache improvement. Since a disfunction of the opioid system has been considered responsible for idiopathic headache and since low beta-endorphin levels have been demonstrated in some idiopathic headaches, particularly in migraine with interparoxysmal headache, we planned this study to verify if histamine therapy is able to modify serum beta-endorphin concentrations. For this purpose, we studied 24 healthy control subjects and 36 patients suffering from migraine with interparoxysmal headache refractory to conventional therapies. Patients showed baseline serum beta-endorphin levels significantly lower than healthy control subjects and treatment with histamine for 15 days increased their beta-endorphin concentrations. We believe that histamine treatment can activate the opioid endogenous system. However, the therapeutic effect of histamine remains to be verified by evaluating the correlation between beta-endorphin levels and headache improvement.

Adult↗