Search PubMed⌕ Search

Biomedical subjects

B Tarquini

Publications and source records attributed to B Tarquini.

At least 37 records · Page 2Linked to original sources
PubMed1988

Prominent circadian absorption of intranasal salmon calcitonin (SCT) in healthy subjects.

In young healthy subjects salmon calcitonin (SCT), intranasally administered, increased in serum as a function of the drug administration time. The serum concentration of a 400 IU SCT dose monitored 10 min after dosing was statistically more significant when inhaled at 0000 than at other, more conventional, administration times (morning or evening). Following dosing at certain times during the day, the serum SCT was less or even questionable with the dose and under the study conditions selected. Dosing without consideration of timing may lead to reduced effect or lack of effect or perhaps ambiguity or controversy regarding the possible circumstance of a "non-absorbent subject". The circadian frequency appears to be a critical determinant of intranasal SCT absorption suggesting administration time to be an important factor in the cost/benefit ratio without the unpleasant side effects sometimes experienced through parenteral routes.

Absorption↗
PubMed1988

[Chronobiological study of ischemic attacks in angina pectoris at rest].

The aims of this study were to determine if the hourly distribution of ischaemic episodes differed as regards ST segment elevation or ST segment depression during ischaemic attacks and differed as regards the degree of coronary atherosclerotic involvement. Twenty-four in-patient drug free subjects with angina at rest underwent ECG continuous Holter monitoring for periods varying from 24 to 168 hours. Four groups of patients were identified: group 1A: 6 patients with ST elevation and 0-1 vessel disease; group 1B: 6 patients with ST elevation and 2-3 vessel disease; group 2A: 3 patients with ST depression and 0-1 vessel disease; group 2B: 9 patients with ST depression and 2-3 vessel disease. During Holter monitoring, 301 ischaemic episodes were registered in group 1A during 576 hours; 173 episodes were registered in group 1B during 624 hours; 41 episodes were registered in group 2B during 528 hours. Using the single and population mean cosinor tests on the episodes of each group, considered as a whole, the following results were found: group 1A showed a circadian rhythm with acrophase at 4:03 a.m. (Fig. 2), group 1B showed a circadian rhythm with acrophase at 10:51 a.m. (Fig. 3), group 2A showed a circadian rhythm with acrophase at 11:15 p.m. (Fig. 5), while group 2B showed ultradian rhythms which lasted 7 and 13 hours (Fig. 6). The chronobiologic analysis of the distribution of the ischaemic attacks confirmed the existence of a circadian rhythm of ischaemic episodes in patients with ST elevation.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗
PubMed1987

Temporal aspects of the pathophysiology of human ulcer disease.

In this paper, a peptic ulcer is considered from the perspective that it is representative of a heterogeneous group of multifactorial determined or influenced disorders having a common pathomorphologic expression. This heterogeneity involves pathophysiological attributes, including both functional (including secretory and motility events and their respective driving mechanisms) and morphologic alterations that relate to mucosal resistance. Patients with duodenal ulcer (DU) have been observed to exhibit alterations, in comparison to normal subjects, in the circadian rhythm characteristics of several gastrointestinal functions. Prominent among these are altered amplitudes of several circadian-organized gastric variables, such as intragastric pH, gastrin, pepsinogen and gastric mitotic index. With respect to any given variable, a reduced group amplitude (a measure of one-half the peak-trough difference of a 24-hr rhythm) could signify an increased dispersion of acrophases (the location of the peak of a circadian rhythm along the 24-hr time scale) reflecting interindividual variation in synchronization schedules, sleep-wake patterns, or chronobiologic alterations. A reduced interindividual amplitude further supports the concept of the heterogeneity of peptic disease. A decrease in the intraindividual amplitude of certain gastric rhythms implies an altered temporal pattern over the 24 hr. This is consistent with the hypothesis of a decrease in the amount of time available for recovery of a given function or set of integrated functions, and hence, increased susceptibility to mucosal injury. Normal high-amplitude variation in gastrointestinal functioning over the 24 hr appears to be required for natural restoration of the gut.

Circadian Rhythm↗
PubMed1987

Intragastric pH continuously monitored in health and in gastric diseases: chronobiologic assessment.

Some gastric diseases clinically show ultradian, circadian, and circannual periodicities. We continuously monitored, during a single 24-hr span, with a fully electronic, solid-state portable recorder, endoluminal gastric pH in five healthy subjects, in some patients with gastric diseases including duodenal ulcer and gastric cancer, and in high-risk persons prone to develop duodenal ulcer and gastric cancer. The daily schedule and the timing of standardized meals for each subject were strictly verified. All stored data (300 time points/subject) were decoded, read, and analyzed by an inferential statistical method to estimate the rhythm parameters. The intragastric dense pH samples showed highly significant circadian and ultradian (8-hr) rhythms in all investigated subjects, but rhythm parameters differed in pre- and in overt pathology.

Duodenal Ulcer↗
PubMed1987

Circadian variability of blood pressure and heart rate in newborns and cardiovascular chronorisk.

At present, neonates are being given screening tests for relatively rare diseases, such as phenylketonuria. The time has come to give emphasis to assessing the risk for major handicapping diseases, such as coronary heart disease, stroke, and certain diseases of the kidney. Modern technology for blood pressure and heart rate monitoring and data analysis provides noninvasive means to determine when preventive measures are indicated.

Blood Pressure↗
PubMed1987

Ultradian (12-hr) significant component in serum prolactin of healthy women and patients with fibrocystic mastopathy.

The 4-hr sampling schedule for a single day demonstrated a prominent circadian rhythm of prolactin (PRL) in clinically healthy women and in mastopathy (FM) patients (with mesor hyperprolactinemia). This chapter reports on differences in time series of serum PRL observed between FM patients and healthy women in the follicular and luteal phases. Thirteen FM patients and six healthy women (controls) were sampled at intervals of 60 min for 24 hr in the two phases of the menstrual cycle. Serum PRL was determined by RIA. The results from spectral analysis of these data showed prominent circadian rhythms and an ultradian (12-hr) significant component in the PRL of controls and FM patients in both phases of the menstrual cycle. The acrophases of the 12-hr rhythms, however, clearly differed in controls and FM patients.

Adult↗
PubMed1986

Serum gastrin and pepsinogen in shift workers.

Gastrointestinal complaints, including peptic ulcer, are believed to be associated and enhanced by shift work (SW). However, there are no clear reports in the literature about this acquired pathology. Serum gastrin (G) and group I pepsinogen (PG1) are thought to play a role in the pathogenesis of peptic ulcer and may be considered a useful test of the gastric function. Five adult male foundry shift workers, without any demonstrated gastrointestinal pathology, were studied over a month's span during the following weekly rotating shift schedule: 07.45-16.45, 06.00-14.00, 14.00-22.00, 22.00-06.00. Six adult, day-working males acted as controls. Blood samples drawn at the beginning and at the end of each weekly shift were assayed for G and PG1 utilizing RIA kits. Our data showed that SW causes a prominent change in the gastrin/acidopepsin secretion system.

Adult↗
PubMed1986

The endogenous secretion rate of human calcitonin in normal conditions.

This paper presents a study on secretion rate for calcitonin in normal healthy subjects, evaluated by an indirect method. A specific radioimmunoassay for monomeric calcitonin was used and the obtained results are lower than those reported by Kanis in 1982. In normal healthy subjects the secretion rate for calcitonin is 1.4 MRC U/day, i.e. ten times less than the value calculated by Kanis. These results will be able to clarify the role of calcitonin and its effects in normal conditions and in several osteoarticular and metabolic bone diseases.

Adolescent↗
PubMed1984

Calcitonin in a chronoepidemiologic perspective.

Calcitonin seasonal (circannual) variations in apparently healthy women and in women suffering from breast cancer in different evolutive-TNM-stage, were studied. Annual values are higher in patients with breast cancer, but there is no correlation with metastases. A significant calcitonin circannual rhythm with acrophase in winter was detectable in controls but not in breast cancer patients. The circannual rhythm obliteration could be a predictive signal of disease and not only metastatic disease.

Adult↗
PubMed1983

Prolactin and prostate: a chronobiologic study.

A possible role of prolactin in prostatic disease has been claimed, but the results are so far misleading. Among the several factors that influence serum prolactin levels, temporal variations, notably circadian, are prominent. This paper shows an impairment in serum prolactin, chronobiologically investigated, in 12 patients with benign prostatic hypertrophy and in 7 patients with prostatic carcinoma. However, a single serum sample cannot be sufficient and may sometimes be misleading if not plotted with an adequate temporal reference standard (chronodesm).

Aged↗
PubMed1981

Circadian aspects of serum prolactin and TSH lowering by bromocriptine in patients with prostatic hypertrophy.

Bromocriptine mesylate lowers the serum concentration of prolactin and TSH in patients with prostatic hypertrophy as a function of drug administration time. The effect of a 2.5-mg dose in lowering these two hormones in presumably similar patients is statistically highly significant and relatively large at unusual test times (in the evening); at other, conventional test or administration times (early morning or midday), it is smaller, questionable, or not demonstrable with the dose and conditions used. Dosing without timing may lead to reduced effect or lack of effect, ambiguity and controversy, and lack of timing may account for the circumstance that an effect of bromocriptine upon TSH in human serum was not previously established. Rigorous assessment of the effect of bromocriptine mesylate upon circulating TSH and prolactin requires consideration of the entire spectrum of rhythms, ultradian and infradian as well as circannual. The circadian approach here analyzed represents a step toward that goal and indicates that the circadian frequency is a critical determinant of this response. Manipulation of TSH concentration in serum, in turn, is of interest in view of the demonstrated alteration of the circannual TSH rhythm in patients with prostatic cancer.

Aged↗
PubMed1981

Mammary cancer risk: circulating TSH and prolactin, fibrocystic breast disease in chronoepidemiologic perspective.

Classical epidemiology associates human breast cancer with several risk factors including, among others, so-called preclinical hypothyroidism, fibrocystic disease of the breast (FM), and hyperprolactinemia. Relationships among FM, hyperprolactinemia, and thyroid function are of interest because of the possibility of multiple risk combinations. Prolactin and TSH (the latter as a presumed index of preclinical hypothyroidism) undergo rhythmic changes and hence should be chronobiologically investigated. Serum samples obtained at 4-hour intervals throughout a 24-hour span from 23 healthy women and from 25 women with FM (histologically verified) here summarized suggest that circadian mesor-hyperprolactinemia is a feature associated with FM. In a broader context, however, such impressions and an often considered modest impairment of thyroid function in some patients must be viewed in the light of new chronobiologic rules. These include a reciprocity of the circannual amplitudes of TSH and prolactin in relation to breast cancer risk, revealed by cooperative studies. A yet broader chronoepidemiologic view reveals that the reciprocal relation of the circannual amplitudes of circulating TSH and prolactin is (sex) inverted in patients with cancer of the prostate.

Adult↗
PubMed1980

Circadian variation of serum prolactin and TSH of women in health or with mammary carcinoma, fibroadenoma or fibrocystic mastopathy.

Prolactin and TSH were determined in serum samples obtained at 4-hourly intervals throughout a 24-hour span from healthy women and from women with fibrocystic mastopathy, fibroadenoma or carcinoma of the breast. Data were subjected to analysis by the population mean-cosinor method. Differences in circadian mesor of prolactin among the 4 groups were statistically significant (P < .01), with healthy women having the lowest value. Prolactin amplitude differences among the groups were of borderline statistical significance (P = .05), while no differences in circadian acrophase were apparent. No statistically significance differences in TSH circadian mesor, amplitude or acrophase could be demonstrated. Individual values from subjects with breast disease were compared with time-qualified tolerance intervals based on data from healthy subjects. If these results can be corroborated on larger populations, sampling about 3 hours after arising may best detect an abnormal serum prolactin elevation. Results from this and other studies indicate the need for multi-variable and multifrequency investigations of breast disease.

Adenofibroma↗
PubMed1979

Circadian variation in urinary melatonin in clinically healthy women in Japan and the United States of America.

Urinary melatonin excretion is lower in East-Asian (Japanese) than in North-American (whites of mixed ethnic origin) women. Moreover, a statistically significant circadian rhythm is demonstrated by population-mean cosinor in the data pool from both groups of women. Furthermore, statistical significance characterizes interactions of effects from geographic differences (between ethnic groups) with temporal factors. Such spatio-temporal interactions await further scrutiny with a view inter alia of carcinogenesis as it is influenced by a spectrum of intermodulating rhythms.

Adult↗