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Sonothromblysis in Combination with Thrombolytic Drugs in a Rabbit Model Using MRI-Guidance

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Engineering（科研） 2013年第10期5卷 352-356页

作者： christakis damianou Nicos Mylonas Kleanthis Ioannides Cyprus University of Technology Cyprus Frederick University Cyprus Limassol Cyprus Polikliniki Ygia Limassol Cyprus

The potential of MRI-guided focused ultrasound (MRgFUS) combined with the thrombolytic drug recombinant tissue plasminogen activator (rt-PA), to dissolve clots in the carotid of a New Zealand rabbitin vivois evaluated. A spherically-focused transducers of 5 cmdiameter;focusing at10 cmand operating at 1 MHz was used. A pulsed ultrasound protocol was used that maintains a tissue temperature increase of less than 1℃?in the clot (called safe temperature). MRgFUS has the potentials to dissolve clots that are injected in the carotid of rabbits in vivo. It was found that the time needed for opening the carotid artery using ultrasound and rt-PA was decreased compared to just using rt-PA. The proposed protocol was monitored using Magnetic Resonance Angiography (MRA) every 1 min.

关键词： Ultrasound MRI Stroke Thrombolysis

Evaluation of the contrast between tissues and thermal lesions in rabbit in vivo produced by high intensity focused ultrasound using fast spin echo MRI sequences

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Journal of Biomedical Science and Engineering 2011年第1期4卷 51-61页

作者： Venediktos Hadjisavvas Kleanthis Ioannides Michalis Komodromos Nikos Mylonas christakis damianou 不详

In this paper the goal was to measure the contrast to noise ratio (CNR) of fast spin echo (FSE) magnetic resonance imaging (MRI) sequences in detecting thermal lesions created by high intensity focused ul-trasound (HIFU) in rabbit kidney, liver, heart, and brain and lamb pancreas. A spherically focused transducer was used which is navigated inside MRI by a custom made positioning device. A simple simu-lation model was developed which predicts the CNR for the two FSE MRI sequences. The maximum con-trast measured with T1-W FSE ranges from 10 to 25. For all 5 tissues of interest if one uses TR between 400 and 500 ms the contrast is maximized. The T1 and T2 value of lesion depends strongly on the host tissue and is always lower than the host tissue. The greater the difference in T1 value, the greater the CNR. The simulated model for predicting the CNR was proven successful. The CNR measured with T2-W FSE varies between 12 and 15 for all 5 tissues. With T2-W FSE if one uses TE between 40 and 50 ms, the contrast is maximized.

关键词： HIFU MRI Kidney Brain Liver Heart Pancreas

Simulation of the Thermal and Mechanical Effects of a Planar Rectangular High Intensity Ultrasound Transducer to Be Used for Destroying Atherosclerotic Plaque

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Engineering（科研） 2013年第10期5卷 347-351页

作者： christakis damianou C. Christofi N. Mylonas Cyprus University of Technology Limassol Cyprus MEDSONIC LTD Limassol Cyprus Frederick University Cyprus Limassol Cyprus MEDSONIC LTD Limassol Cyprus

The aim of this study is to perform a simulation study of the thermal and mechanical effects of a flat rectangular (3×10 mm2),MRI compatible transducer operating at 5 MHz for the purpose of destroying atherosclerotic plaque. The simulation study focuses on measuring the plaque destruction (due to the thermal of mechanical mode of ultrasound) as a function of power, time, frequency, duty factor and pulse duration. The main goal is to keep the artery temperature at a safe level. The simulation study shows that with the thermal mode the temperature in the artery cannot be kept at a safe level.

关键词： Ultrasound Atherosclerotic Plaque MRI

Evaluation of fast spin echo MRI sequence for an MRI guided high intensity focused ultrasound system for in vivo rabbit liver ablation

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Journal of Biomedical Science and Engineering 2010年第3期3卷 241-246页

作者： Nicos Mylonas Kleanthis Ioannides Venediktos Hadjisavvas Dimitris Iosif Panayiotis A. Kyriacou christakis damianou 不详

The effectiveness of magnetic resonance imaging (MRI) to monitor thermal lesions created by High Intensity Focused Ultrasound (HIFU) in rabbit liver in vivo is investigated. The MRI sequences of T1- weighted, and T2-weighted fast spin echo (FSE) were evaluated. The main goal in this paper was to find the range of repetition time (TR) and range of echo time (TE) which maximizes the contrast to noise ratio (CNR). An ultrasonic transducer operating at 2 MHz was used, which is navigated using a positioning device. With T1W FSE the range of TR under which CNR is maximized ranges from 400 to 900 ms. The maximum contrast measured is approximately 25. With T2W FSE the range of TE that establishes maximum contrast is between 40 ms and 80 ms, with CNR of approximately 14. T1W FSE is much better than T2W FSE in detecting thermal lesions in liver. Both T1W and T2 W FSE were proven successful to image thermal lesions created by HIFU in rabbit liver in vivo.

关键词： Ultrasound Liver MRI Lesion Ablation

MRI monitoring of lesions created at temperature below the boiling point and of lesions created above the boiling point using high intensity focused ultrasound

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Journal of Biomedical Science and Engineering 2010年第8期3卷 763-775页

作者： christakis damianou Kleanthis Ioannides Venediktos Hadjisavvas Nikos Mylonas Andreas Couppis Demetris Iosif Panayiotis A. Kyriacou 不详

Magnetic Resonance Imaging (MRI) was utilized to monitor lesions created at temperature below the boiling point and lesions created at temperature above the boiling point using High Intensity Focused Ultrasound (HIFU) in freshly excised kidney, liver and brain and in vivo rabbit kidney and brain. T2-weighted fast spin echo (FSE) was proven as an excellent MRI sequence that can detect lesions with temperature above the boiling point in kidney. This advantage is attributed to the significant difference in signal intensity between the cavity and the thermal lesion. In liver the MRI sequence of Proton Density is recommended to detect lesions above boiling. In brain T1-W FSE was the optimum pulse sequence to detect lesions of either type. In order to monitor the temperature elevation during a HIFU exposure, T1-weighted fast spoiled gradient (FSPGR) was used. The shape of the focal temperature distribution was uniform with the absence of boiling, whereas with an exposure affected by boiling, the temperature distribution could be of irregular shape, demonstrating the drastic effects taking place during boiling. In order to confirm that boiling occurred, the temperature was estimated using the widely used method of Proton Resonance Frequency (PRF) shift.

关键词： Ultrasound Kidney Brain Liver MRI Lesion

Studies on the Authenticity of Local Wines by Spectroscopic and Chemometric Analysis

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Journal of Chemistry and Chemical Engineering 2014年第2期8卷 101-107页

作者： Rebecca Kokkinofta Naso Economidou Eleni Tzioni Katerina damianou Konstantina Poulli Chara Savvidou Charalambos Louka Popi Kanari State General Laboratory Ministry of Health Nicosia 1451 Cyprus

The authenticity of 91 wines produced in Cyprus from both indigenous and other vine varieties were investigated by a holistic approach, using, advanced technology such as SNIF-NMR （site-specific natural isotopic fractionation-nuclear magnetic resonance） and 1R-MS （isotope ratio-mass spectrometry） for the determination of the stable isotopes and ICP （inductively coupled plasma spectroscopy） for some heavy metals. The spectroscopic characteristics were evaluated statistically using different chemometric methods. The dependency of the D/H （deuterium/hydrogen） ratio of the methylene site in the ethanol molecule （D/H）ll and also theδ ^18O values of the wine water, were the most useful discriminators. Isotopic results allow us to have a complete idea about the regional variability of the isotopes. Among the metals, Ni followed by Pb was the ones with the highest discrimination value. The determined concentrations of Pb, Ni, Cr and Cd that are related to the safety of wines were within the acceptable limits that have been established by the OIV （international organization of vine and wine） or comparable with the results of the wines of other European countries. The study of the correlation between the load of heavy metals and isotopes in wines showed a dependence on the grape variety but not the geographical location of the vineyard. This is probably due to the close proximity of wine regions in Cyprus.

关键词： SNIF-NMR IR-MS ICP Cypriot wines authenticity stable isotopes heavy metals chemometrics.

Phenolic Antioxidants in Cypriot Wines as a Tool for Their Varietal Discrimination： Preliminary Results

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Journal of Chemistry and Chemical Engineering 2014年第8期8卷 810-818页

作者： Rebecca Kokkinofta Eleni Tzioni Naso Economidou Katerina damianou Eleni Prokopiou Anna Krashia Myriam Frantzi Eleni Kakouri Popi Kanari State General Laboratory Ministry of Health Nicosia 1451 Cyprus

A total of 56 wines from different vintages and wine-growing regions of Cyprus were used to analyze six biologically interesting phenolic antioxidants （gallic acid, catechin, vanillic acid, epicatechin, coumaric and feroulic acid） by high performance liquid chromatography. The study includes red and white Cypriot authentic wines from local and imported varieties that were produced under the same vinification conditions at a Model Winery. Results extracted after the chemometric analysis of the measured concentrations show a strong relationship of the phenolic antioxidative capacity with the variety of the wines and gallic acid followed by vanillic acid found in the highest concentrations of the other antioxidants studied. Comparing the concentrations found with bibliographic data for wines from other countries, it was found that, the concentration levels of vanillic and ferulic acid were significantly higher for Cypriot wines.

关键词： Wine antioxidants phenolic compounds HPLC (high performance liquid chromatography) Cypriot wines chemometrics.

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Z[X]中根在单位圆内的首1整系数多项式

数学译林 2001年第4期20卷 346-349页

作者： PantelisA.damianou 王树桂等

Restless legs syndrome is contributing to fatigue and low quality of life levels in hemodialysis patients

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World Journal of Nephrology 2017年第5期6卷 236-242页

作者： Christoforos D Giannaki Michael Hadjigavriel Akis Lazarou Aristos Michael Loukas damianou Efthimios Atmatzidis Ioannis Stefanidis Georgios M Hadjigeorgiou Giorgos K Sakkas Marios Pantzaris Department of Life and Health Sciences University of NicosiaNicosia CY 1700Cyprus the Cyprus Institute of Neurology and Genetics Nicosia CY 1683Cyprus Hemodialysis Unit Larnaca General HospitalLarnaca CY 6021Cyprus Hemodialysis Unit Limassol General HospitalLimassol CY 3304Cyprus School of Medicine University of Thessaly41110 LarisaGreece Faculty of Sport and Health Sciences University of St Mark and St JohnPlymouth PL6 8BHUnited Kingdom

AIM To examine whether hemodialysis(HD) patients with restless legs syndrome(RLS) are subjects of greater fatigue and impaired quality of life(QoL) compared to HD patients without *** Eighty five stable HD patients participated in this study. According to their RLS status, the patients were dividedinto the RLS group(n = 23) and the non-RLS group(n = 62). QoL, fatigue, sleep quality, daily sleepiness and depression symptoms were assessed by using various questionnaires. Finally, biochemical parameters including iron, ferritin, hemoglobin, hematocrit and parathormone were assessed. RESULTS The HD patients with RLS scored worse in all the questionnaires used in the study(P < 0.05). The patients with RLS were more likely to receive the HD therapy on the morning shift, whilst 43.5% of the RLS patients reported to experience the RLS symptoms also during HD. The severity of RLS was correlated with fatigue, depression score and sleep quality(P < 0.05). CONCLUSION HD patients with RLS are subject to lower QoL related parameters and greater fatigue compared to HD patients without RLS. RLS should be successfully managed in order to improve the QoL of the sufferers.

关键词： Sleep quality Depression Secondary restless legs syndrome Fatigue Quality of life