RadPhysBio: A Radiobiological Database for the Prediction of Cell Survival upon Exposure to Ionizing Radiation.

Based on the need for radiobiological databases, in this work, we mined experimental ionizing radiation data of human cells treated with X-rays, γ-rays, carbon ions, protons and α-particles, by manually searching the relevant literature in PubMed from 1980 until 2024. In order to calculate normal and tumor cell survival α and ß coefficients of the linear quadratic (LQ) established model, as well as the initial values of the double-strand breaks (DSBs) in DNA, we used WebPlotDigitizer and Python programming language. We also produced complex DNA damage results through the fast Monte Carlo code MCDS in order to complete any missing data. The calculated α/ß values are in good agreement with those valued reported in the literature, where α shows a relatively good association with linear energy transfer (LET), but not ß. In general, a positive correlation between DSBs and LET was observed as far as the experimental values are concerned. Furthermore, we developed a biophysical prediction model by using machine learning, which showed a good performance for α, while it underscored LET as the most important feature for its prediction. In this study, we designed and developed the novel radiobiological 'RadPhysBio' database for the prediction of irradiated cell survival (α and ß coefficients of the LQ model). The incorporation of machine learning and repair models increases the applicability of our results and the spectrum of potential users.

Graph-Based Disease Prediction in Neuroimaging: Investigating the Impact of Feature Selection.

In biomedical machine learning, data often appear in the form of graphs. Biological systems such as protein interactions and ecological or brain networks are instances of applications that benefit from graph representations. Geometric deep learning is an arising field of techniques that has extended deep neural networks to non-Euclidean domains such as graphs. In particular, graph convolutional neural networks have achieved advanced performance in semi-supervised learning in those domains. Over the last years, these methods have gained traction in neuroscience as they could be the key to a deeper understanding in clinical diagnosis at the systems or network level (for an individual brain but also for across a cohort of subjects). As a proof-of-principle, we study and validate a previous implementation of graph-based semi-supervised classification using a ridge classifier and graph convolutional neural networks. The models are trained on population graphs that integrate imaging and phenotypic information. Our analysis employs neuroimaging data of structural and functional connectivity for prediction of neurodevelopmental and neurodegenerative disorders. Here, we particularly study the effect of different strategies to reduce the dimensionality of the neuroimaging features on the graph nodes on the classification performance.

Analyzing the Effect of Weak External Transcranial Magnetic Stimulation on the Primary Dominant Frequencies of Alzheimer Patients Brain by Using MEG Recordings.

Backround and Objectives: Alternative, non-invasive, and non-pharmaceutical options are gaining place in the battle of Alzheimer's Disease treatment control. Lately, the magnetic stimulation of the brain is the most prevalent technique with encouraging results. The aim of this study is to establish any possible change on the Primary Dominant Frequencies (PDF) (range 2-7 Hz) of the affected brain regions in Alzheimer Disease (AD) patients after applying extremely weak Transcranial Magnetic Stimulation. Materials and Methods: For this purpose, all AD patients were scanned with the use of MagnetoEncephaloGraphy (MEG) recordings through a whole-head 122-channel MEG system. Results: Our results exerted statistically significant PDF changes due to weak TMS accompanied by rabid attenuation of clinical symptoms. Conclusion: Thus, this is the first time that a positive therapeutic effect is being demonstrated even at pico-Tesla range magnetic fields in a small clinical group of studies for AD.

We Used a Double Blind Experiment to Investigate Weak pT-TMS in Epilepsy Patients.

Magnetoencephalographic recordings, external picoTesla Transcranial Magnetic Stimulation (pT-TMS) and a double blind experimental design were used for the evaluation of 10 epilepsy patients (three males, seven females). Their ages ranged from 23 to 48 years. Our results showed an enhancement in the 2-7 Hz frequency range in five out of nine patients who had a statistically significant difference (55%). The pT-TMS could be a significant means for the treatment of epilepsy. Further research should be done prior to have final conclusions.

MAGNETO-THERAPY IN PHYSIOTHERAPY UNITS: INTRODUCTION OF QUALITY CONTROL PROCEDURE DUE TO LACK OF MAINTENANCE.

Rehabilitation practice for many patients consisting of a combined use of magneto therapy resulting emission of low frequency magnetic fields to the patient, elicit concerns about occupational exposure to electromagnetic radiation (EMR) for the operators. The time extended use of the device periodically leads to mechanical failures or troubleshooting of the machine which, in most cases, are not perceived by the operator of the device. All device's efficient functionality have a major impact on the completion of the treatment procedure in a large percentage of specific clinical conditions. If the device's operating condition is technically out of order or in a mode of over-activity, operators are mainly seeking solutions by reviewing the clinical case of the patient. This eliminates their contribution during the primary therapeutic plan or increases the treatment sessions. In this work, an extended survey is presented including 75 physiotherapy centres concerning usability and maintenance issues of magneto therapy devices throughout Greek territory combined with extended measurements of Electromagnetic Radiation in the unit room were performed. Physiotherapists' perceptions revealed lack of technical support, maintenance and safe use of magneto therapy devices that extract auxiliary observations upon their clinical practice routines. Additionally safety measurements have not revealed field strengths over International Reference Levels which could result health risks for users and coexisting patients. The pilot survey that conducted in Attica and Western Greece confirms that magnetic fields strength that are measured are in accordance with the statutory legislation but will, at the same time, revealed lack of maintenance of the devices. Deficiency in topics such as proper equipment function will necessitate the creation of quality safety protocols, concerning the use of magneto-therapy, with the main aim the improvement of treatment procedures for the higher performance of therapeutic rehabilitation services to patients. Finally in this work, the proposal of a QC protocol for magnetotherapy devices is proposed for evaluation.

MEG recordings of patients with cerebral palsy before and after the application of pico-Tesla weak magnetic fields.

MEG data for five cerebral palsy patients were taken using a whole-head 122-channel MEG system. An experiment was designed to identify the possible effect of external pico-Tesla weak magnetic fields. The subjects were five male volunteers 17-46 years of age. External stimulation, field amplitude 1-7.5 pico-Tesla, was applied to each subject at their alpha-rhythm frequency. Fast Fourier transforms were applied to the data of all MEG channels and the rhythms of the patients were evaluated before and after pico-Tesla transcranial magnetic stimulation. The appliance of pico-Tesla weak magnetic fields showed the brains of the cerebral palsy patients had an enhance of the frequencies of (2-7 Hz) for each patient. This was followed by an improvement and normalization of their MEG. The results had a statistical significance in four out of five subjects (80%) and suggested the stimulation provided a positive contribution to the management of the symptoms of cerebral palsy patients.

Microwave diathermy induces mitogen-activated protein kinases and tumor necrosis factor-α in cultured human monocytes.

Although rehabilitation practice for most patients consists of a combined use of thermotherapy that is produced from diathermy devices resulting faster and deeper heating to the patient, major concerns about occupational exposure to electromagnetic radiation for the operators must be considered. In most occasions, physiotherapists have involved multi-hour treatment sessions to different patients, resulting overuse of the diathermy device. Recently, our team along with other groups have raised serious concerns about the occupational safety aspects related to microwave diathermy (MWD) use. Driven by these recent reports, in this work, we tried to investigate the in vitro effects of a physiotherapist routine MWD device regarding its potential inflammatory biological effects that could be evoked in human cultured monocytes. Our results show that MWD does not alter the integrity of the cell membrane and, consequently, the viability of monocytes as assessed by Trypan blue and MTT measurements. Then again, members of the MAPK family (p38 and ERK1/2) were activated upon MWD exposure at 5-30 min, eventually leading to a time-dependent considerable increase in TNF-α production, a key pro-inflammatory mediator. Our results are indicative of a stress-activated phenomenon of monocytes upon MWD radiation, which could trigger potential hazardous cellular outcomes due to thermal and/or non-thermal bystander effects. Our results deserve further investigation, planned by our team in due course, to delineate the clinical correlations of these findings.

The Effect of pT-TMS on Beta Rhythm in Children with Autism Disorder. A MEG Study.

We investigated the beta rhythm in 10 children with autism disorders (six boys and four girls) aged 5-12 (mean± SD: 8.3± 2.1) before and after the application of pico Tesla transcranial magnetic stimulation (pT-TMS) using magnetoencephalography (MEG). The MEG was car-ried out in a magnetically shielded room with a whole-head 122-channel gradiometer. After applying pT-TMS, we observed a beta rhythm increase towards the frequency range of 18-26 Hz in seven out of 10 patients (70%). We created a score that rated the level of improvement for each patient: 1=some change; 2=minor change; and 3=major change. All patients had an improvement in their clinical symptoms after the application of pT-TMS. There was a correlation between the clinical score and the increase of channels in the frequency range 18-26 Hz after pT-TMS. We concluded that the application of pT-TMS affected the beta rhythm in children with autism disorder. Therefore, more studies need to be further conducted.

MICROWAVE DIATHERMY IN PHYSIOTHERAPY: INTRODUCTION AND EVALUATION OF A QUALITY CONTROL PROCEDURE.

Microwave diathermies (MWDs) are electromagnetic (EM) radiation emitting systems that are used by physiotherapists for thermotherapy treatment. Although this form of therapy is widely available in most physiotherapy units worldwide, management of the equipment is not obligatory addressed either by clinical engineers or medical physicists. A novel quality control (QC) protocol for MWD equipment, examining mechanical, electrical and electronic condition, the power output and EM radiation distribution in the electrotherapy room, was used during a national QC survey. The results of the survey revealed serious concerns about the safety of users and coexisting patients. The proposed approach could result in the introduction of EM-screened rooms, ensuring that MWD users and other persons in the vicinity will not be exposed to EM radiation over reference levels. International bodies could develop specific directives for EM radiation exposure in Physiotherapy Units, to conform to the proposed acceptance and functioning criteria for MDWs.

Microwave diathermy in physiotherapy units: a survey on spatial and time heterogeneity of the electromagnetic field.

Microwave diathermy (MWD) is a therapeutic system that has been in use for some decades now in all physiotherapy settings, following the regulations of national facility establishments. The validity of diathermy devices is probably reduced as their working time increases, introducing the need for the device to be controlled/reset by qualified personnel in order to maintain its effectiveness in sessions and to accurately deliver the energy output that the physiotherapist asks for. However, while MWD has been a vital tool for practising physiotherapists, there is no clear evidence of a health burden due to incorrect usability. Additionally, due to the fact that physiotherapy rooms contain physiotherapeutic equipment it is observed that during the use of the diathermy device there is spatial heterogeneity in the interior space. In this work, the results are presented of the first national survey for quality control of MWD systems installed in physiotherapy rooms existing in urban and rural areas in Greece. Serious concerns about the technical status of the equipment as well as staff and patient safety, regarding the levels of non-ionising radiation emitted from MWD devices, are discussed. Additional evaluation is included of measurements in empty physiotherapy rooms while the MWD unit is transmitting at three different input powers (50 W/100 W/150 W-these are the therapeutic protocols used most frequently by physiotherapists) and in fully equipped physiotherapy rooms. Field strengths measured around MWDs normally working at different angles, distances and times compared to international limits revealed great spatial and time heterogeneity, raising serious concerns about the safety of occupational workers or other patients.

A combined study of MEG and pico-Tesla TMS on children with autism disorder.

Magnetoencephalographic (MEG) recordings from the brain of 10 children with autism (6 boys and 4 girls, with ages range from 5-12 years, mean[Formula: see text][Formula: see text][Formula: see text]SD: 8.3[Formula: see text][Formula: see text][Formula: see text]2.1) were obtained using a whole-head 122-channel MEG system in a magnetically shielded room of low magnetic noise. A double-blind experimental design was used in order to look for possible effect of external pico-Tesla Transcranial Magnetic Stimulation (pT-TMS). The pT-TMS was applied on the brain of the autistic children with proper field characteristics (magnetic field amplitude: 1-7.5[Formula: see text]pT, frequency: the alpha - rhythm of the patient 8-13[Formula: see text]Hz). After unblinding it was found a significant effect of an increase of frequencies in the range of 2-7[Formula: see text]Hz across the subjects followed by an improvement and normalization of their MEG recordings. The statistical analysis of our results showed a statistical significance at 6 out of 10 patients (60%). It is also observed an increase of alpha activity in autistic children at the end of one month after pT-TMS treatment at home. In conclusion, the application of pT-TMS has the prospective to be a noninvasive, safe and important modality in the management of autism children.

Combined MEG and pT-TMS study in Parkinson's disease.

Magnetoencephalographic (MEG) recordings of the brain in Parkinson's disease were obtained in order to look for possible effect of pico-Tesla transcranial magnetic stimulation (pT-TMS). We found a significant effect of an increase of frequencies in the range of 2-7 Hz across subjects. In addition, we observed the mean peak frequency difference within the 2-7 Hz band towards frequencies of less or equal to those frequencies of the alpha frequency range (8-13 Hz).

The Effects of Sweet, Bitter, Salty and Sour Stimuli on Alpha Rhythm. A Meg Study.

OBJECTIVE: the possible diff erences in processing gustatory stimuli in healthy subjects was investigated by magnetoencephalography (meg). MATHERIAL AND METHOD: meg recordings were evaluated for 10 healthy volunteers (3 men within the age range 20-46 years, 7 women within the age range 10-28 years), with four diff erent gustatory stimuli: sweet, bi" er, sour and salty. Fast fourier transform was performed on meg epochs recorded for the above conditions and the eff ect of each kind of stimuli on alpha rhythm was examined. OUTCOMES: A significant higher percent of alpha power was found irrespective of hemispheric side in all gustatory states located mainly at the occipital, le$ and right parietal lobes. One female volunteer experienced no statistically signifi cance when comparing normal with salty and sour taste respectively. Two female volunteers exhibited no statistically signifi cance when comparing their normal with their salty taste. One male volunteer experienced no statistically signifi cance when comparing the normalbitter and normal-salty states correspondingly. All the other subjects showed statistically signifi cant changes in alpha power for the 4 gustatory stimuli. CONCLUSION: The pattern of activation caused by the four stimuli indicated elevated gustatory processing mechanisms. This cortical activation might have applicability in modulation of brain status.

MEG as a Medical Diagnostic Tool in the Greek Population.

Magnetoencephalography (MEG) is the recording of the magnetic field produced by the flowing of ions in the brain. This article reports our experience in the application of MEG in patients and healthy volunteers in the Greek population. We provide a brief description of our research work. The MEG data were recorded in a magnetically shielded room with a whole-head 122 channel or an one-channel biomagnetometer. Our results lead us to believe that the MEG is an important research field which is evolving quickly with a number of interesting findings with respect to normal and abnormal functions of the human brain. It could provide clinical practice with an easy to perform non invasive method, which could be adjunct to conventional methods for the evaluation of brain disorders.

Feature extraction of osteoporosis risk factors using artificial neural networks and genetic algorithms.

A hybrid model that consists of an Artificial Neural Network and Genetic Algorithm is used in order to select the most significant osteoporosis risk factors. The results indicated that just 8 to 10 parameters, out of a total 34, are essential in order of high performance to be achieved.

Hiatal hernia predisposes to nocturnal gastro-oesophageal reflux.

BACKGROUND: Nocturnal reflux has been associated with severe complications of gastro-oesophageal reflux disease and a poorer quality of life. Hiatal hernia predisposes to increased oesophageal acid exposure, but the effect on night reflux symptoms has never been investigated. The aim of the study was to investigate if hiatal hernia is associated with more frequent and severe night reflux symptoms. METHODS: A total of 215 consecutive patients (110 male, mean age 52.6 ± 14.7 years) answered a detailed questionnaire on frequency and severity of specific day and night reflux symptoms. Subsequently, all patients underwent upper endoscopy and were categorized in two groups based on the endoscopic presence of hiatal hernia. RESULTS: Patients with hiatal hernia were more likely to have nocturnal symptoms compared to those without hiatal hernia (78.6 vs. 51.8%, p = 0.0001); 59.2% of patients with hiatal hernia reported heartburn and 60.2% regurgitation compared to 43.8 and 39.3% of those without hiatal hernia, respectively (p = 0.033 and p = 0.003). The proportions of patients with day heartburn or regurgitation were not significantly different between the two groups. Night heartburn and regurgitation were graded as significantly more severe by patients with hiatal hernia (4.9 ± 4.2 vs. 3.2 ± 3.7, p = 0.002, and 3.8 ± 4.2 vs. 2.2 ± 3.5, p = 0.001, respectively). Patients with hiatal hernia had more frequent weekly night heartburn and regurgitation compared to those without hiatal hernia (p = 0.004 and p = 0.008, respectively). CONCLUSIONS: More patients with hiatal hernia reported nocturnal reflux symptoms compared to those without hiatal hernia. Furthermore, nocturnal reflux symptoms were significantly more frequent and graded as significantly more severe in patients with presence of hiatal hernia rather than in those without hiatal hernia.

Genetic algorithm pruning of probabilistic neural networks in medical disease estimation.

A hybrid model consisting of an Artificial Neural Network (ANN) and a Genetic Algorithm procedure for diagnostic risk factors selection in Medicine is proposed in this paper. A medical disease prediction may be viewed as a pattern classification problem based on a set of clinical and laboratory parameters. Probabilistic Neural Network models were assessed in terms of their classification accuracy concerning medical disease prediction. A Genetic Algorithm search was performed to examine potential redundancy in the diagnostic factors. This search led to a pruned ANN architecture, minimizing the number of diagnostic factors used during the training phase and therefore minimizing the number of nodes in the ANN input and hidden layer as well as the Mean Square Error of the trained ANN at the testing phase. As a conclusion, a number of diagnostic factors in a patient's data record can be omitted without loss of fidelity in the diagnosis procedure.

Nitric oxide, ammonia, and CRP levels in cirrhotic patients with hepatic encephalopathy: is there a connection?

GOALS: Comparison of nitric oxide (NO) levels in cirrhotic patients with and without hepatic encephalopathy (HE), evaluation of possible correlation between HE and other clinical or laboratory characteristics, and estimation of utilization of NO levels in clinical practice. BACKGROUND: HE is a neuropsychiatric complication of cirrhosis. The exact pathogenetic mechanisms underlying the presence of HE are not known. However, dysfunction of the NO pathway and ammonia detoxification are thought to play a major role. STUDY: Sixty-seven cirrhotic patients, 36 (53.7%) without HE, and 31 (46.3%) with HE were included in the study. Eighteen healthy individuals were used as control group. Clinical and laboratory data, including ammonia and stable end products of NO using Griess reaction, were collected. RESULTS: NOx levels were statistically significantly higher in cirrhotic patients (225.5 µmol/L) than in control group [(67.94 µmol/L) (P=0.000)]. NOx levels were, also, statistically significantly higher in patients with HE compared with patients without HE (324.67 µmol/L vs. 141.96 µmol/L, P=0.000). Significant correlation between the presence of HE and NOx, ammonia, C-reactive protein, albumin, Model for End-Stage Liver Disease score, and Child-Pugh classification revealed. NOx levels also correlated with severity of HE. NOx and ammonia are independent factors predicting HE according to regression analysis. Diagnostic accuracy for the diagnosis of HE using a combination of NOx and ammonia was superior compared with standalone NOx or ammonia utilization. CONCLUSIONS: NOx levels are correlated with the presence and severity of HE. NOx levels determination, in addition to ammonia levels, could contribute in diagnosis of HE.

Do proton pump inhibitors attenuate the effect of aspirin on platelet aggregation? A randomized crossover study.

It is common practice to coadminister proton pump inhibitors with aspirin to diminish the risk of upper gastrointestinal bleeding. This is the first study that investigated the potential impact of a proton pump inhibitor on aspirin effects on platelet aggregation. Twenty-four hypertensive subjects eligible for treatment with low-dose enteric-coated aspirin (LDECA) for primary prevention of cardiovascular disease were randomized to receive 100 mg LDECA or 100 mg LDECA plus 30 mg lansoprazole for 4 weeks. Then, participants were crossed over to the alternative regimen for another 4 weeks. Salicylic, gastrin, and pepsinogen I blood level counting were used to ensure adherence to treatment. Platelet aggregation was evaluated by light transmittance aggregometry and PFA100. The LDECA administration reduced arachidonic acid (P < 0.001), collagen (P < 0.01), and epinephrine (P < 0.001) tests. These changes paralleled an increase in collagen/epinephrine duration (P < 0.001) but not in collagen/adenosine diphosphate duration and platelet count. No significant difference was found in any of these platelets' function tests with LDECA alone versus LDECA plus lansoprazole. A significant increase in salicylic levels was observed in patients on LDECA as well as in those on LDECA plus lansoprazole, whereas gastrin and pepsinogen I levels were increased only when lansoprazole was added. These data suggest that the concomitant use of the lansoprazole at 30-mg daily does not influence the long-term effect of LDECA on platelet aggregation. Furthermore, they might imply that an interaction of LDECA with other proton pump inhibitors on platelet aggregation is unlikely.

Effects of ageing on small bowel video-capsule endoscopy examination.

OBJECTIVES: The effects of ageing on small bowel video-capsule endoscopy (VCE) studies have not been studied prospectively yet. METHODS: We prospectively investigated 120 consecutive VCE studies. Patients were divided into three age groups: <40, 40-64, and > or =65 yr. Two independent investigators examined the completion of the examination and measured the VCE gastric transit time (GTT), small bowel transit time (SBTT), and the proportion of VCE SBTT without clean intestinal mucosa. They also recorded study findings. RESULTS: We examined the videos of 32 (26.7%), 36 (30%), and 52 (43.3%) patients aged under 40, 40-64, and over 64 yr, respectively. VCE completion (cecum visualized) rate was similar in the three groups (81.2%, 77.8%, and 78.8%, respectively, P= 0.96). There was no difference in GTT (P= 0.22) and in SBTT (P= 0.8) among the three age groups. Although in univariate analysis, there was a trend (P= 0.057) for higher proportion of SBTT without clean mucosa in patients over 64 yr (22.65 [12.42-32.22]%) versus patients under 40 (12.65 [4.57-30.7]%) and patients aged 40-64 yr (12.55 [6.12-31.32]%), multivariate linear regression analysis has not confirmed this difference. Older patients had significantly less erosions and normal studies, but they had more angiodysplasias (P < 0.05). All four tumors were detected in the elderly. CONCLUSIONS: Ageing does not affect the completion rate and the quality of bowel preparation for VCE. However, elderly patients have fewer normal studies and more angiodysplasias and tumors in the small bowel.