Biomedical subjects

S Coda

Publications and source records attributed to S Coda.

22 records · Page 2Linked to original sources

PubMedDate not supplied

[Determination of the "presumptive risk" of hypertensive crisis with fractal interpolation of 24-hour arterial pressure. II: study with secondary hypertensive patients].

PURPOSE: The present study applies the "fractal interpolation" (FI) to 24-h blood pressure nonivasively and ambulatorily monitored over a day-night period in secondary hypertensives. The purpose is the evaluation of the prevalence for a "presumptive risk" (PR) of hypertensive crisis. MATERIALS AND METHODS: The study was carried out in 108 cases of secondary hypertension, who were non-invasively and ambulatorily monitored for their 24-h blood pressure values. The FI was applied to the time-qualified values of the mean arterial pressure. RESULTS: The PR of hypertensive crisis was found in 11% of the investigated secondary hypertensive patients. Such a risk shows a not significant prevalence in dippers as compared to non-dippers, and in those who showed a significant blood pressure circadian rhythm as compared to those who showed the blood pressure circadian rhythm to be abolished. Additionally, a not significant difference was found between the cases "at risk" and "not at risk" as far as the spectrum of harmonic formants of the 24-h blood pressure pattern is concerned. CONCLUSIONS: The PR of hypertensive crisis is not associated with the dipping/non-dipping phenomenon as well as the circadian rhythmicity of blood pressure. Its occurrence in secondary hypertensives is essentially related to the disorder that is detectable in blood pressure non-linear variability. Therefore, such a risk may be caused by neurovegetative mechanisms which notoriously confer a non-linear chaotic variability to 24-h blood pressure pattern.

Adult↗

PubMedDate not supplied

[Identification of "presumptive risk" of hypertension crises with fractal interpolation of the 24-hour arterial pressure. III: study of normotensive subjects].

PURPOSE: The present study is devoted to identify the normotensive subjects who are at a "presumptive risk" (PR) for hypertensive crisis, by applying the "fractal interpolation" (FI) to blood pressure 24-h pattern. MATERIALS AND METHODS: The investigation was performed on 109 ascertained cases of normotension, who underwent a non-invasive ambulatory monitoring of their 24-h blood pressure, by applying the FI to their daily mean arterial pressure. RESULTS: The study showed that the PR for hypertensive crisis can be found in 12% out of the investigated normotensives. The proportion of such a risk is not significantly higher in non-dippers as compared to dippers. Vice versa, the prevalence of cases with a PR for hypertensive crisis was found to be significantly increased in normotensives who were deprived by a significant blood pressure circadian rhythm as compared to those who showed the blood pressure circadian rhythm to be preserved. Furthermore, the cases "at risk" were found to show a different spectrum for the harmonic formants which compose the complex harmonic structure of the blood pressure 24-h variability. CONCLUSIONS: The PR for hypertensive crisis in normotensives seems to be increased by the loss of the blood pressure circadian rhythm, due to a change in the harmonic structure which confers the 24-h periodicity to the hemodynamic variable. This means that the abrogation of the blood pressure circadian rhythm in conditions of normotension promotes an adjunctive disorder for which the PR for hypertensive crisis is augmented.

Adult↗

PubMedDate not supplied

[Daily sensation of hunger, before and after phototherapy, in subjects with depression-type seasonal affective disorder].

OBJECTIVE: The present study investigates the daily pattern of hunger sensation (HS) in women affected by "seasonal affective disorder--depression type" (SAD-DT), before and after therapeutic exposure to bright light (phototherapy). The aim is to detect whether there are disorders in daily HS during the active phase of the disease which can be normalized by an effective treatment of the depressive status, via phototherapy. MATERIALS AND METHODS: Volunteered for the study 4 women affected by SAD-DT, 32-58 years old (BMI: 17.8-29.6 Kg/m2); 10 clinically healthy women (CHW), 21-52 years old (BMI: 23 e 25 Kg/m2) were recruited as controls. Both of the SAD-DT patients and CHW were asked to compile the "orexigram", which was chronobiometrically analyzed by means of the 1. conventional statistical methods; 2. rhythmometric analysis; 3. spectral analysis. RESULTS: Before phototherapy, the SAD-DT patients were found to be characterized by an increased HS (hyperorexia), with the circadian rhythm of the orectic stimulus (OS) which is shifted in its acrophase, being prone to become "free running". After phototherapy, the SAD-DT patients were found to show a little insignificant decrease in their OS, which still maintains a delayed phase in its circadian rhythm as well as the tendency to be "free running". CONCLUSIONS: The pre-treatment findings suggest that the SAD-DT patients are affected by hyperorexia associated with a "phase-shift" for the circadian periodicity of their HS, which is prone to the desynchronization. Such a dyschronism reinforces the hypothesis that the SAD-DT may be pathogenetically sustained by a mechanism of "phase-shift". The post-treatment findings suggest that both the hyperorexia and dyschronism of the orectic circadian rhythm are uncorrected by the phototherapy, even though the SAD-DT patients seem to have had beneficial antidepressive effects from the therapeutic intervention. The persisting dyschronism indicates that the photic stimulus is not able to completely reset the biological clock of the suprachiasmatic nuclei, at least for the phasic modulation of the HS circadian rhythm. The orexigram, thus, could be enclosed among the clinical tools in order to assess the complete efficacy of the phototherapy in SAD-DP patients.

Adult↗

PubMedDate not supplied

Circadian rhythm of hunger sensation in patients affected by dysthymic disorder.

PURPOSE: The present study investigates the daily pattern of hunger sensation (HS), namely orexia, in patients affected by "Dysthymic Disorder" (DD). The aim is to detect whether there are changes in the circadian rhythm (CR) of HS, herein investigated as a "marker rhythm", that can reveal a dysfunction of the "circadian biological clock" (CBC). In such a circumstance, one could be authorised to suggest a resynchronizing therapy, via antidepressant chronizing drugs and/or morning exposure to bright light, as it is currently done in other types of human depression, having a documented dysfunction of the CBC. MATERIALS AND METHODS: Volunteered with informed consent for the study 6 women (age = 34-56 years; mean BMI = 22.7 +/- 4.8 kg/m2) affected by DD. 10 clinically healthy women (CHW, age = 21-52 years; mean BMI = 24.0 +/- 0.5 kg/m2) were recruited as the controls. Both of the dysthymic patients (DP) and CHW were asked to compile the "orexigram", which was chronobiometrically analyzed by means of the 1. conventional statistical methods; 2. rhythmometric analysis for the CR; 3. spectral analysis for the harmonic components of the orexigram. RESULTS: The DP were found to be characterized by a normal daily level of HS, with 1. the CR of the orectic stimulus to be preserved and well located in its acrophase, and 2. the spectrogram of the orexigram to be substantially well configured. CONCLUSIONS: The above-cited results suggest that the DP show no alterations in the HS marker rhythm that can be taken as an evidence for declaring that the DD is not characterized by a relevant dysfunction of the CBC. Lacking in particular a phase-shift in HS marker rhythm, it can be argued that the DD is an affective disorder for which a resynchronizing therapy (exposure to bright light or pharmacological chronizers) seems to be "a priori" not indicated.

Adult↗