Biomedical Photonics (BMP - E-Journal)
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РАЗРАБОТКА И ЭКСПЕРИМЕНТАЛЬНЫЕ ИССЛЕДОВАНИЯ НЕЙРОПОРТА ДЛЯ ТЕРАПИИ ГЛИОМЫ ГОЛОВНОГО МОЗГА
Get PDFCurrent paper presents the results of the system development for intracranial implantation aimed on therapy and prevention of brain gliomas relapse. The main property of the system, in prospective, will be to direct the growth of glioma cells localized in the region adjacent to the site of the removed tumor along the fi bers towards the proximal part of the fiber-optic scaffold (neuroport). Such approach will allow carrying out cells diagnostics by the photoluminescence signal and provide subsequent destruction of malignant cells by photodynamic action. Besides, this system could be used for monitoring the processes occurring in the probed area in order to control the possible relapses. The localization of cells along the fi ber structures covered with gelatin compound, which is the source of amino acids during cultivation, was shown during the glioma cells growth dynamics study. Moreover, four different designs of intracranial scaffold models, serving as ports for diagnostic and therapeutic laser radiation delivery, were developed and successfully tested in the framework of the research. The results obtained on the rats brain with induced tumors (glioma C6) after neuroport implantation demonstrate sufficiently intense fluorescence in the tumor bed after intravenous injection of the nonmetallic sulfonated phthalocyanine based photosensitizer, and a pronounced photodynamic effect leading to total destruction of the tumor. In this way, the results of this study open the prospects of creating the neuroport with an internal fi ber structure that focuses the glioma cells growth
КЛИНИЧЕСКИЕ ЗАДАЧИ ПРЯМОЙ ДОЗИМЕТРИИ (IN VIVO) ПРИ КОНТАКТНОЙ ЛУЧЕВОЙ ТЕРАПИИ
Get PDFThe use of multicomponent methods of special treatment (surgery, polychemotherapy, radiation therapy, laser photodynamic therapy) in oncology requires the control of doses in the tumor and healthy organs with high accuracy. A method of direct dosimetry using fiber-optic scintillation dosimeter MCD-4 is proposed. The dosimeter is fixed on endostats and is visualized on CT/MRI. The coordinates are entered into the anatomical units and dosimetry calculations, the data are mapped, the doses are adjusted on medical grounds. The developed technique of direct dosimetry allows monitoring of the contact radiation therapy (CRT) procedure in real time and making the necessary changes and corrections during the treatment. The refinement of the absorbed dose values using calculations and direct dosimetry minimizes the risk of complications and ensures the possibility of effective use of other treatment methods, including photodynamic therapy, after CRT
ПРЕСС-РЕЛИЗ VI ВСЕРОССИЙСКОЙ КОНФЕРЕНЦИИ С МЕЖДУНАРОДНЫМ УЧАСТИЕМ «ФОТОДИНАМИЧЕСКАЯ ТЕРАПИЯ И ФОТОДИАГНОСТИКА»
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ФОТОДИНАМИЧЕСКАЯ ИНАКТИВАЦИЯ ПАТОГЕННЫХ БАКТЕРИЙ В БИОПЛЕНКАХ С ИСПОЛЬЗОВАНИЕМ НОВЫХ СИНТЕТИЧЕСКИХ ПРОИЗВОДНЫХ БАКТЕРИОХЛОРИНА
Get PDFBacteriochlorins as the antimicrobial photosensitizers have a promising future in the face of the unrelenting increase in antimicrobial resistance. The goal of this study was to investigate the infl uence of lipophilicity and number of positively charged substituents in these molecules on the photodynamic inactivation (PDI) of biofi lm bacteria in vitro. Testing how bacteriochlorin derivatives with different properties affect microbes will allow to determine the optimal ratio of these parameters within a single molecule. We have investigated 4 bacteriochlorin derivatives, all of which were synthesized in Organic Intermediates and Dyes Institute. These were: hydrophobic neutral meso-tetra(3-pyridyl) bacteriochlorin (ВС1), amphyphilic tetracationic meso-tetra(1- undecyl-3-pyridyl)bacteriochlorin tetrabromide (ВС2), hydrophilic tetracationic meso-tetra[1-(4'-bromobutyl)-3-pyridyl]bacteriochlorin tetrabromide (ВС3) and octacationic meso-tetra[1-(4'-pyridiniobutyl) -3-pyridyl]bacteriochlorin octabromide (ВС4) . The water-soluble cationic bacteriochlorin derivatives showed the most effective PDI of bacteria in biofi lms. While tetracationic BC3 caused total inactivation of S. aureus 15, octacationic BC4 was bactericidal for P. aeruginosa 32 to the same degree (>99.999%). Interestingly, increasing the number of cationic substituents from 4 to 8 in bacteriochlorin molecules enhances bactericidal action against gram-negative bacteria in biofi lms. The lack of charge-carrying groups and high degree of lipophilicity of PS have negative impact on PDI of biofi lm bacteria. Bacterial membrane damage as a result of PDI can be one of the causes of cell death
НЕИНВАЗИВНАЯ ОЦЕНКА ЛОКАЛЬНОЙ ТЕМПЕРАТУРЫ НАГРЕВА БИОТКАНЕЙ ПОД ДЕЙСТВИЕМ ЛАЗЕРНОГО ИЗЛУЧЕНИЯ ПО СПЕКТРАМ ЛЮМИНЕСЦЕНЦИИ ИОНОВ Nd3+
Get PDFLaser hyperthermia is one of the promising methods for treatment of oncological diseases. For routine clinical use of hyperthermia, it is necessary to control the uniformity and localization of heat within the tumor. Local heating can be achieved by using special thermal agents, such as nanoparticles doped with rare-earth ions. Measurement of the temperature of the thermal agents will allow timely regulation of the applied laser radiation excitation power and optimization of the hyperthermia process.The paper presents the results of a study on the non-invasive determination of the YPO4 nanoparticles doped with Nd3+ temperature with sensitivity of 0.2% °С-1 in 30-60°С temperature range. The temperature of the nanoparticles was calculated from the Nd3+ luminescence spectra in the 800-1000 nm range under excitation into 4F5/2 energy state by 805 nm laser. A calibration procedure for recalculating the ratio of the luminescence intensities from the Stark sublevels of the 4F3/2 Nd3+ state into the values of the real NP temperature in accordance with the Boltzmann distribution is given. An algorithm for calculating luminescence intensities for individual Stark components is proposed. After calculating the intensities corresponding to each individual Stark component, all the intensities related to the transition from the upper and lower Stark sublevels of the 4F3/2 state are summed, and then their ratio is calculated. The resulting ratio is normalized to the value of the ratio at room temperature and, in accordance with the calibration dependence, is recalculated into the NP heating temperature. It was demonstrated that the investigated 1%Nd3+:YPO4 nanoparticles can be used as "primary” thermometers that do not require additional recalibration to evaluate the temperature in the range used for hyperthermia
ФОТОДИНАМИЧЕСКАЯ ТЕРАПИЯ ЛЕЙКОПЛАКИИ ГОЛОВКИ ПОЛОВОГО ЧЛЕНА (КЛИНИЧЕСКОЕ НАБЛЮДЕНИЕ)
Get PDFIn the publication, the authors present a clinical case of successful application of photodynamic therapy with photolon – a chlorin series photosensitizer, in a young patient with leukoplakia of the glans penis. Photolon was administered in a dose of 2 mg/kg 2.5 hours before photodynamic therapy (light dose 50 J/cm2) The treatment included 3 sessions of photoirradiation with 1 month interval. The authors note complete regression of pathological foci and long-term clinical remission (more than 6 months).В публикации авторы представили клинический случай успешного применения фотодинамической терапии с фотолоном – фотосенсибилизатором хлоринового ряда, у пациента с лейкоплакией головки полового члена. Фотолон вводили в дозе 2 мг/кг за 2,5 ч до проведения облучения (световая доза 50 Дж/см2). Проведенное лечение включало 3 курса фотодинамической терапии с интервалом в 1 мес. В результате проведенного лечения получена полная регрессия патологических очагов и длительная клиническая ремиссия (более 6 мес)
Математическая модель обнаружения внутриэритроцитарных инфекций с помощью оптоакустического метода
Get PDFMalaria causes a serious health problem in the tropical and subtropical regions of the globe. In many cases, the consequences of this disease are fatal. Therefore, a simple, fast, accurate and affordable diagnostic system for the early detection of this disease is necessary for the timely administration of antimalarial drugs.The malarial parasite, during its intra-erythrocyte development, processes a significant amount of hemoglobin, which in this case turns into a hem form called hemozoin. Hemozoin and hemoglobin have different molar extinction coefficients at certain optical wavelengths, hence, light absorption and an optoacoustic signal (OAS) from the infected cell will be different from that of a healthy cell. The paper describes the developed theoretical model intended for studying the influence of intra-erythrocyte malarial parasite development on optoacoustic signals. The OAS were calculated based on the models of healthy and infected blood modeled on the basis of a 3D model.The simulated OAS were analyzed in the temporal and frequency domains to obtain signs of infection at various stages. The calculated OAS spectra have different amplitude levels, which indicates that the optoacoustic method can be useful for differentiating various intraerythrocyte stages of the malarial parasite. The carried out modeling and the results obtained allow us to continue working on the creation of an optoacoustic flow cytometer
ПРИМЕНЕНИЕ МЕТОДОВ ЛАЗЕРНОЙ ФОТОНИКИ В ОРТОПЕДИЧЕСКОЙ СТОМАТОЛОГИИ ДЛЯ НЕИНВАЗИВНОГО БЕСКОНТАКТНОГО ИССЛЕДОВАНИЯ ОБЪЕМНЫХ МИКРОДЕФОРМАЦИЙ КОСТНЫХ ТКАНЕЙ
Get PDFModern methods of laser photonics, which make it possible to measure the dynamics of micro-deformations of volumetric objects without contact and with high sensitivity, find increasing application in a wide variety of fields. Particularly attractive is the use of such a delicate, non-perturbing technique in medicine. The article reports on experiments using laser photonics methods in dental implantology, which allowed to give practical medical recommendations. In the work, a study was made of the possibilities of holographic and speckle interferometry methods for measuring the deformation of the jaw bone tissue with a step-by-step installation of cylindrical and conical mini implants. The possibility of determining the relaxation time of deformations after the installation of mini implants was demonstrated. The purpose of this work is to justify the possibility and feasibility of using laser photonics to solve this medical problem.Современные методы лазерной фотоники, позволяющие бесконтактно с высокой чувствительностью измерять динамику микроде- формаций объемных объектов, находят все более широкое применение в самых разнообразных областях. Особенно привлекательно применение такой деликатной, не возмущающей объект методики в медицине. Цель настоящей работы – обосновать возможность и целесообразность применения лазерной фотоники в ортопедической стоматологии для неинвазивного бесконтактного исследования объемных микродеформаций костной ткани. В статье приведены результаты экспериментов с использованием методов лазерной фотоники в стоматологической имплантологии, позволивших дать практические медицинские рекомендации. В частности, в работе проведено исследование возможностей методов голографической и спекл-интерферометрии для измерения деформирования костной ткани челюсти при пошаговой установке мини-имплантов цилиндрической и конической формы. Продемонстрирована возможность определения времени релаксации деформаций после установки мини-импланто
ОПЕРАТИВНЫЙ АНАЛИЗ СЛОЖНЫХ МЕДИЦИНСКИХ СОСТОЯНИЙ МЕТОДАМИ ФОТОНИКИ
Get PDFIn this paper we analyze the possibility of using special methods and equipment of coherent photonics when working with multi-parameter information. Inverse two-phase coding and operational analysis of multi-parameter data can realize a number of probabilistic algorithms. The possibility and expediency of realization of not only the correlation algorithm underlying the holographic image recognition but also universal statistical algorithms using photonics methods is substantiated. A comparative analysis of photonic medical diagnostic systems running on a wide range of algorithms: search for precedent, correspondence diagnostics, deterministic diagnostics, Bayes algorithm. The results of experimental studies of medical diagnosis and the prediction of complex conditions is presented. Such an analysis is carried out by the means of vector-matrix multiplication using laser photonics methods. It is significant that with the widening of the range of probability algorithms, it is possible to preserve certain advantages of the holographic method: multidimensionality, efficiency, high information capacity and speed, visibility and flexibility of the result presentation. The methods described are of particular relevance in connection with the first photonic processors