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Dive into the research topics where P. Anninos is active.

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Featured researches published by P. Anninos.


International Journal of Neuroscience | 1991

Magnetic Stimulation in the Treatment of Partial Seizures

P. Anninos; N. Tsagas; Reuven Sandyk; Kyriakos Derpapas

We have recently demonstrated that Magnetoencephalographic (MEG) brain measurements in patients with seizure disorders show significant MEG activity often in the absence of conventional EEG abnormalities. We localized foci of seizure activity using the mapping technique characterized by the ISO-Spectral Amplitude (ISO-SA) on the scalp distribution of specified spectral components or frequency bands of the emitted MEG Fourier power spectrum. In addition, using an electronic device, we utilized the above recorded activity to emit back the same intensity and frequency of magnetic field to the presumed epileptic foci. Using this method we were able, over the past two years, successfully to attenuate seizure activity in a cohort of over 100 patients with various forms of epilepsy. We now present in more detail three randomly selected patients with partial seizures in whom application of an external artificial magnetic field of low intensity produced a substantial attenuation of seizure frequency during an observation period extending from 10 to 14 months. All patients had previously obtained only partial response to conventional anticonvulsant therapy. Attenuation in seizure frequency was associated with normalization of the MEG activity. These cases demonstrate that artificial magnetic treatment may be a valuable adjunctive procedure in the management of partial seizures. The possible mechanisms underlying the anticonvulsant properties of magnetic stimulation at both cellular and systemic levels are discussed. Specifically, since the pineal gland has been shown to be a magnetosensitive organ which forms part of a combined compass-solar clock system, and since it exerts an inhibitory action on seizure activity in both experimental animals and humans, we discuss the potential pivotal role of the pineal gland in the long term anticonvulsant effects of external artificial magnetic stimulation.


International Journal of Neuroscience | 1992

Melatonin as a Proconvulsive Hormone in Humans

Reuven Sandyk; N. Tsagas; P. Anninos

The pineal gland and melatonin exert a major influence in the control of brain electrical activity and have been shown to be involved in seizure and sleep mechanisms. Since pinealectomy has been reported to result in seizures in experimental animals, it is assumed that melatonin has anticonvulsant properties. Indeed, limited studies in humans with temporal lobe epilepsy indicate that melatonin attenuates seizure activity. In the present communication we present evidence, based on magnetoencephalographic (MEG) brain measurements, that melatonin may exert proconvulsive activity in humans as well. The proconvulsive properties of melatonin may explain several phenomena associated with epilepsy such as the increased occurrence of seizures at night when melatonin plasma levels are 5 to 8-fold higher than during the day and the observed exacerbation of seizures premenstrually and during pregnancy as well as the attenuation of seizures in the menopause. Furthermore, our findings suggest that anticonvulsants which decrease melatonin secretion, such as the benzodiazepines, may exert their antiepileptic activity by attenuating nocturnal melatonin secretion. Finally, we propose that patients with nocturnal epilepsy or those experiencing exacerbation of seizures premenstrually may benefit from the administration of agents which block the secretion or action of melatonin.


Brain Topography | 2000

Nonlinear Analysis of Brain Activity in Magnetic Influenced Parkinson Patients

P. Anninos; Adam Adamopoulos; Kotini A; Nicholaos Tsagas

Magnetoencephalogram (MEG) recordings were obtained from the brain of patients suffering from Parkinsons disease (PD) using the Superconductive Quantum Interference Device (SQUID). For each patient the magnetic activity was recorded from a total of 64 points of the skull (32 points from each temporal lobe) as defined by a recording reference system, which is based on the 10-20 Electrode Placement System. Some of the recorded points were observed to exhibit abnormal rhythmic activity, characterized by high amplitudes and low frequencies. External magnetic stimulation (EMS) with intensity 1-7.5pT, and frequency the a-rhythm of the patient (8-13 Hz) was applied in the left-right temporal, frontal-occipital and vertex (2 minutes over each of the above regions) and the brain magnetic activity was recorded again. The application of the EMS resulted in rapid attenuation of the MEG activity of PD patients. Furthermore, chaotic dynamic methods were used, in order to estimate the correlation dimension D of the reconstructed phase spaces. The estimated values of D, in conjunction with the results derived from the other data analysis methods, strongly support the existence of low dimension chaotic structures in the dynamics of cortical activity of PD patients. In addition, the increased values of D of the MEG after the application of EMS when compared with the corresponding ones obtained from the MEGs prior to the EMS, suggest that the neural dynamics are strongly influenced by the application of EMS.


Brain Topography | 2002

Detection of non-linearity in schizophrenic patients using magnetoencephalography

Kotini A; P. Anninos

Objective: The aim of this study is to investigate the presence of any non-linearity in the magnetoencephalographic recordings (MEG) from the temporal lobe of schizophrenic patients in comparison with controls, in order to find the differences underlying the brain waves. We calculated the correlation dimension, which is a measure of the complexity of the dynamic system, as well as the first Lyapunov exponent that indicates the systems unpredictability. Methods: The schizophrenic group consisted of 3 men and 7 women aged 23-32 years (mean 27.2, SD=3.5) and the control group of 3 men and 6 women aged 26-35 years (mean 31.6±4.1). There were no significant differences between the two groups as far as age and sex were concerned. None of them received any medication. Results: The analysis of the MEG in the schizophrenic group showed lower dimension complexity and moreover the first Lyapunov exponent presented lower values compared with the corresponding ones in the control group, which means lower information processing. Conclusion: EEG findings as determined by MEG and non-linear analysis may offer important perspectives to better understand brain function in schizophrenia.


International Journal of Neuroscience | 1991

Magnetic fields and seasonality of affective illness: Implications for therapy

Reuven Sandyk; P. Anninos; N. Tsagas

Seasonal affective disorder is characterized by recurrent winter depression associated with hypersomnia, overeating, and carbohydrate craving. The severe form of winter depression affects about 5% of the general population and is believed to be caused by light deficiency. About 70%-80% of patients with winter depression experience attenuation of symptoms when exposed to bright light therapy. Hypotheses pertaining to the pathogenesis of winter depression implicate the effects of light on different characteristics of circadian rhythms. One of the environmental factors which may be implicated, in addition to light, in the pathophysiology of winter depression is the geomagnetic field. There is strong indication that the pineal gland is a magnetosensitive system and that changes in the ambient magnetic field alter melatonin secretion and synchronize the circadian rhythms. In man, shielding of the ambient magnetic field significantly desynchronizes circadian rhythms which could be gradually resynchronized after application of magnetic fields. The strength of the environmental magnetic field diminishes during the winter months, leading to increased susceptibility for desynchronization of circadian rhythms. Thus, since the acute application of magnetic fields in experimental animals resembles that of acute exposure to light with respect to melatonin secretion (i.e., suppression of melatonin secretion), magnetic treatment might be beneficial for patients with winter depression. In addition, since the environmental light and magnetic fields, which undergo diurnal and seasonal variations, influence the activity of the pineal gland, we propose that a synergistic effect of light and magnetic therapy in patients with winter depression would be more physiological and, therefore, superior to phototherapy alone.(ABSTRACT TRUNCATED AT 250 WORDS)


International Journal of Neuroscience | 1991

Is the Pineal Gland Involved in the Pathogenesis of Endometrial Carcinoma

Reuven Sandyk; P. G. Anastasiadis; P. Anninos; N. Tsagas

The pathogenesis of endometrial carcinoma, which is the most common malignant neoplasm of the female genital tract, is unknown. It is believed that a prolonged period of increased estrogenic exposure unopposed by progesterone may underlie the malignant transformation of the endometrial cells. In the following communication, we propose that deficient melatonin functions may be an additional endocrine factor implicated in the pathogenesis of endometrial carcinoma. This hypothesis is based on the observations that: (a) melatonin has antiestrogenic properties; (b) melatonin stimulates progesterone production which opposes the action of estrogens; (c) an increased rate of endometrial hyperplasia, a premalignant condition, has been noted during the winter, a time of year associated with diminished melatonin secretion; (d) an increased incidence of anovulatory cycles, which is a risk factor for endometrial carcinoma, occurs in the winter; (e) melatonin secretion decreases sharply during the menopause, a period associated with an increased risk of endometrial carcinoma; (f) obesity, which is a major risk factor for endometrial carcinoma, is associated with impaired circadian melatonin secretion; (g) diabetes mellitus, which is an additional risk factor for endometrial carcinoma, is associated with decreased melatonin secretion and an increased rate of pineal calcification; and (h) the prevalence of endometrial carcinoma is lower in the black population compared to the white population. Similarly, the incidence of pineal calcification, which reflects the secretory activity of the gland, is significantly lower in the African and American black populations as compared to the white population.(ABSTRACT TRUNCATED AT 250 WORDS)


International Journal of Neuroscience | 1989

Localization and Cure of Epileptic Foci with the Use of Meg Measurements

P. Anninos; N. Tsagas

Systematic studies with pathological subjects with focal and general epilepsies using magnetoencephalographic (MEG) measurements showed significant brain activities even if they are not present in the electroencephalogram EEG. Using a mapping technique characterized by an isospectral amplitude (ISO-SA) of the scalp distribution of specified spectral components or frequency bands of the MEG power spectrum we were able to localize the epileptic foci. This localization of epileptic foci gives us information on the emitted magnetic field intensity and frequency for each focal point on the map of the patient. Using this information we can cure the patient by adjusting an electronic device which can emit back to the specific scalp point a magnetic field of the same intensity and frequency as the one which-is emitted from it. The principle of this technique is based on the physical phenomenon of Youngs double-slit experiment by which under certain condition light plus light gives darkness.


Brain Topography | 2003

Magnetic Stimulation Can Modulate Seizures in Epileptic Patients

P. Anninos; Kotini A; Adam Adamopoulos; N. Tsagas

Objective: The aim of this study is to investigate the influence of external magnetic stimulation (EMS) in epileptic patients using magnetoencephalographic (MEG) measurements and non-linear analytic techniques. Methods: The examined group consisted of 15 men aged 19-56 years (mean: 39.5±11.3) and 15 women aged 15-53 years (mean: 36.7±11.4 ). For each one the magnetic activity was recorded from 32 points for each temporal lobe. External magnetic stimulation (EMS) with proper field characteristics (intensity: 1-7.5 pT, frequency: the α-rhythm of the patient (8-13 Hz)) was applied in the frontal, occipital and temporal lobes for 2 to 6 minutes and the emitted brain magnetic activity was recorded again. In order to investigate if there is any alteration in the MEG complexity underlying the neural dynamics characterizing the pathologic brain before and after the EMS, chaotic analysis approach was applied for the estimation of the dimensional analysis of the existing strange attractors. Results: The application of EMS resulted in rapid attenuation of the MEG activity of epileptic patients. The obtained results of the dimensionality calculation provide a shift from lower to higher dimensional values. Such a shift is an indication that we are dealing with a chaotic system similar with the one characterizing normal subjects. Conclusions: The increased values of the dimensional complexity and the lower activity of the MEG after the application of EMS strongly supports the beneficial effects of EMS in epileptic patients.


Journal of Obstetrics and Gynaecology | 2001

Linear analysis of fetal magnetocardiogram recordings in normal pregnancies at various gestational ages

Kotini A; P. Anninos; A. Adamopoulos; K. Avgidou; G. Galazios; P. Anastasiadis

In this study we investigated the fetal magnetocardiogram recordings (FMCG) in 64 women, 21-30 years old, with single normal pregnancies and gestational ages 28-40 weeks. Spectral analysis was used to quantify heart rate variability and to identify the maturation of the autonomic nervous system. According to our results, there was an increase of the ratio LF/HF of the power spectrum, which reflects the maturation of the autonomous nervous system and also an increase in heart rate variability in the course of pregnancies, which was statistically significant (ANOVA test, P < 0·0005) comparing the R-R intervals of the number of cases in the four groups of 28-30, 37-40, 31-33 and 37-40 weeks of gestation. This study highlights some of the advantages of FMCG as a novel, non-invasive technique for obtaining useful clinical information.In this study we investigated the fetal magnetocardiogram recordings (FMCG) in 64 women, 21-30 years old, with single normal pregnancies and gestational ages 28-40 weeks. Spectral analysis was used to quantify heart rate variability and to identify the maturation of the autonomic nervous system. According to our results, there was an increase of the ratio LF/HF of the power spectrum, which reflects the maturation of the autonomous nervous system and also an increase in heart rate variability in the course of pregnancies, which was statistically significant (ANOVA test, P < 0.0005) comparing the R-R intervals of the number of cases in the four groups of 28-30, 37-40, 31-33 and 37-40 weeks of gestation. This study highlights some of the advantages of FMCG as a novel, non-invasive technique for obtaining useful clinical information.


Journal of Integrative Neuroscience | 2011

MEG evaluation of taste by gender difference

T. Gemousakakis; Kotini A; P. Anninos; Athanassios Zissimopoulos; Panos Prassopoulos

Magnetoencephalographic recordings were evaluated in five different states: normal condition, sweet, bitter, sour, and salt taste. Twenty-eight healthy volunteers, 14 male and 14 female, ranging from 12 to 50 years of age, were included in the study. The results showed that, in the normal condition, as well as in the sweet and the bitter taste, the male volunteers exhibited a higher count of low-frequency than high-frequency channels compared to the femal ones; in the case of the sour taste, there was no clear differentiation between the genders; with the salt taste, the female volunteers exhibited a higher count of low-frequency channels whereas there was no clear differentiation in the number of high frequencies between the gender. A discrimination in the spatial distribution of the frequencies provides novel insights into the identification of gender-related taste sensation.

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Kotini A

Democritus University of Thrace

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Adam Adamopoulos

Democritus University of Thrace

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N. Tsagas

Democritus University of Thrace

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Anastasiadis P

Democritus University of Thrace

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Koutlaki N

Democritus University of Thrace

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Reuven Sandyk

Albert Einstein College of Medicine

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Panos Prassopoulos

Democritus University of Thrace

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Efthimios Sivridis

Democritus University of Thrace

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Haritomeni Piperidou

Democritus University of Thrace

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Ioannis Seimenis

Democritus University of Thrace

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