Altered Resting State Effective Connectivity of Anterior Insula in Depression

Depression has been associated with changes in both functional and effective connectivity of large scale brain networks, including the default mode network, executive network, and salience network. However, studies of effective connectivity by means of spectral dynamic causal modeling (spDCM) are still rare and the interaction between the different resting state networks has not been investigated in detail. Thus, we aimed at exploring differences in effective connectivity among eight right hemisphere brain areas—anterior insula, inferior frontal gyrus, middle frontal gyrus (MFG), frontal eye field, anterior cingulate cortex, superior parietal lobe, amygdala, and hippocampus, between a group of healthy controls (N = 20) and medicated depressed patients (N = 20). We found that patients not only had significantly reduced strength of the connection from the anterior insula to the MFG (i.e., dorsolateral prefrontal cortex) but also a significant connection between the amygdala and the anterior insula. Moreover, depression severity correlated with connectivity of the hippocampal node. In conclusion, the results from this resting state spDCM study support and enrich previous data on the role of the right anterior insula in the pathophysiology of depression. Furthermore, our findings add to the growing evidence of an association between depression severity and disturbances of the hippocampal function in terms of impaired connectivity with other brain regions

Psychopathology Assessment Methods Revisited: On Translational Cross-Validation of Clinical Self-Evaluation Scale and fMRI

We present in this article a study design that combines clinical self-assessment scale, simultaneously administered with fMRI data acquisition. We have used a standard block-design with two different conditions. Each active block consisted of four text statements (items), alternating diagnostically specific (DS) blocks comprising items from von Zerssen depression scale and diagnostically neutral (DN) blocks with items from a questionnaire about general interests. All items were rated on four degree Likert scale, and patients provided responses with corresponding four buttons during the fMRI session. Our results demonstrated that in healthy controls, contrasting the two types of stimuli yielded no residual activations, e.g., the DS did not produce significantly different activations compared to the DN stimuli. Furthermore, the correlation analyses did not find a relationship between brain activations and the total score of the DS statements in this group. However, contrasting the DS stimuli to the DN stimuli in the patients produced significant residual activations in several brain regions: right pre- and postcentral gyrus (including right supramarginal gyrus), left middle frontal gyrus, triangular part of the left inferior frontal gyrus and middle temporal gyrus. The left precuneus demonstrated correlations with the patients’ DS score. In the between-group comparisons, we found residual activations in the right pre- and postcentral gyrus, right supplementary motor area, medial segment of the right precentral gyrus, right superior parietal lobule, left middle frontal gyrus, left superior frontal gyrus, left occipital pole. Our results confirm the possibility of translational cross-validation of a clinical psychological test (von Zerssen’s depression scale) and fMRI. At this stage, however, we can only confirm the sensitivity of the method (its ability to distinguish healthy controls from depressed patients), but we cannot conclude anything about its specificity (distinction from different psychopathology conditions)

Altered resting state effective connectivity of anterior insula in depression

Depression has been associated with changes in both functional and effective connectivity of large scale brain networks, including the default mode network, executive network, and salience network. However, studies of effective connectivity by means of spectral dynamic causal modeling (spDCM) are still rare and the interaction between the different resting state networks has not been investigated in detail. Thus, we aimed at exploring differences in effective connectivity among eight right hemisphere brain areas—anterior insula, inferior frontal gyrus, middle frontal gyrus (MFG), frontal eye field, anterior cingulate cortex, superior parietal lobe, amygdala, and hippocampus, between a group of healthy controls (N = 20) and medicated depressed patients (N = 20). We found that patients not only had significantly reduced strength of the connection from the anterior insula to the MFG (i.e., dorsolateral prefrontal cortex) but also a significant connection between the amygdala and the anterior insula. Moreover, depression severity correlated with connectivity of the hippocampal node. In conclusion, the results from this resting state spDCM study support and enrich previous data on the role of the right anterior insula in the pathophysiology of depression. Furthermore, our findings add to the growing evidence of an association between depression severity and disturbances of the hippocampal function in terms of impaired connectivity with other brain regions

Clinical Investigations: Somatosensory Evoked Potentials in Full-Term Neonates With Perinatal Asphyxia

OBJECTIVE: To explore the capacity of somatosensory evoked potentials (SEP) to assess maturation processes in the development of the nervous system, and the characteristics of SEP in healthy full-term infants and full-term newborns with perinatal asphyxia and their follow up until the age of 14 months

Jubilee Scientific Conference "Medicine of the Future" - 29-31 October 2020 on the occasion of the 75th Anniversary of Medical University of Plovdiv

Plenary lectures    7Oral presentations    32-    Biomedicine    32-    Biopharmacy    46-    Contemporary surgical techniques    51-    Innovative methods of diagnosis and treatment    58-    Dental medicine    61-    Public Health/Healthcare    67Poster sessions    74    -    Poster session I    74        •    Biomedicine    74        •    Biopharmacy    90        •    Contemporary surgical techniques    94        •    Innovative methods of diagnosis and treatment    96        •    Dental medicine    99        •    Public Health-Healthcare    103    -    Poster session II    116        •    Projects with national/international funding    116Intra-university project session    120    -    Intra-university projects 2016-2018    120    -    Doctoral projects 2015-2017    142    -    Post-doctoral projects 2018    15

Heart Rate Variability as a Method for Assessment of the Autonomic Nervous System and the Adaptations to Different Physiological and Pathological Conditions

The autonomic nervous system controls the smooth muscles of the internal organs, the cardiovascular system and the secretory function of the glands and plays a major role in the processes of adaptation. Heart rate variability is a non-invasive and easily applicable method for the assessment of its activity. The following review describes the origin, parameters and characteristics of this method and its potential for evaluation of the changes of the autonomic nervous system activity in different physiological and pathological conditions such as exogenous hypoxia, physical exercise and sleep. The application of heart rate variability in daily clinical practice would be beneficial for the diagnostics, the outcome prognosis and the assessment of the effect of treatment in various diseases

THE EFFECT OF SMOKING ON THE AUTONOMIC HEART REGULATION IN YOUNG "HEALTHY" MALE SMOKERS.

The aim of our study was to compare the autonomic nervous system (ANS) activity between young “healthy” male smokers and non-smokers via the method of heart rate variability (HRV). Pulse oximetry, blood pressure, time and frequency domain and non-linear HRV parameters were measured in 21 healthy non-smoker males aged 28.0 ± 7.4 (mean±SD) and fourteen “healthy” smoker males aged 28.1±4.3 with 9.2±5.6 pack-years resting in supine position. Smokers were instructed to refrain from smoking at least 2 hours before the test. There was no difference between smokers and non-smoker, regarding oxygen saturation (96.3±1.6 vs 96.8±1.2% p=0.330) and blood pressure (117.4±9.4/75.5±7.1 vs 119.5±6.4/77.2±7.1 mmHg p=0.312) but smokers had higher heart rate at rest (76.3±14.2 vs 65.2±9.0 b/min p=0.008). Smokers had decreased standard deviation of normal-to-normal interval (SDNN) (40.3±16.3 vs 62.0±32.1 ms p=0.013) and root mean square of the successive differences (RMSSD) (24.9±12.5 vs 59.3±32.8 ms <0.001). Frequency domain analysis showed that smokers had decreased total power (lnTP) (7.0±0.8 vs 7.7±1.1 ms2 p=0.046), but higher LF/HF index (2.3±0.9 vs 1.4±0.8 p=0.004). Sample entropy was higher in non-smokers (1.4±0.3 vs 1.6±0.2 p=0.049). Cigarette smoking altered autonomic nervous function measured by HRV in young “healthy” males in the absence of subjective clinical signs or symptoms. The method may be applied in the clinical practice to detect early changes in the ANS activity