Doped Barium Titanate at Intermediate Stages of Synthesis of ВТО

This paper presents the results of synthesis and characterization of calcium 0doped nanocrystalline barium titanate powder with different concentration of doped elements ((Ba1-xCax) TiO3, were x 0; 0.02; 0.06; 0.1; 0.16; 0.2), produced by oxalate route. Calcium additives were added on the surface the samples of semidecomposed barium titanil oxalate. For synthesis were used simultaneously decomposition of unstable barium, titanium compositions and calcium salts. The semidecomposed barium titanil oxalate and doped barium titanate characterization carried out by specific surface area measurements, TEM, X-Ray. It is experimentally shown that Са2+ introduction reduces lattice parameter for samples that related with replacement of barium by calcium. Solubility of calcium in barium titanate nanopowders increase from 10 at % up to 16 at %. The second phase appears at 20 at %. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3547

The differences between Cis-and Trans-Gene inactivation caused by heterochromatin in Drosophila

Position-effect variegation (PEV) is the epigenetic disruption of gene expression near the de novo-formed euchromatin-heterochromatin border. Heterochromatic cis-inactivation may be accompanied by the trans-inactivation of genes on a normal homologous chromosome in trans-heterozygous combination with a PEV-inducing rearrangement. We characterize a new genetic system, inversion In(2)A4, demonstrating cis-acting PEV as well as trans-inactivation of the reporter transgenes on the homologous nonrearranged chromosome. The cis-effect of heterochromatin in the inversion results not only in repression but also in activation of genes, and it varies at different developmental stages. While cis-actions affect only a few juxtaposed genes, trans-inactivation is observed in a 500-kb region and demonstrates а nonuniform pattern of repression with intermingled regions where no transgene repression occurs. There is no repression around the histone gene cluster and in some other euchromatic sites. trans-Inactivation is accompanied by dragging of euchromatic regions into the heterochromatic compartment, but the histone gene cluster, located in the middle of the trans-inactivated region, was shown to be evicted from the heterochromatin. We demonstrate that trans-inactivation is followed by de novo HP1a accumulation in the affected transgene; trans-inactivation is specifically favored by the chromatin remodeler SAYP and prevented by Argonaute AGO2

Experimental study of VEGF immune expression dynamics in the retina using photoinduced BRVO model

Aim. To describe the dynamics of vascular endothelial growth factor (VEGF) immune expression in the retina using the model of photoinduced branch retinal vein occlusion (BRVO) and to establish the terms of neovascularization appearance.Materials and methods. BRVO was modelled on 21 chinchilla rabbits (21 eyes) weighing 1.5‑2 kg (fellow eyes served as controls). Photosensitizer «Fotoditazin» (2.5 mg / kg) was injected intravenously. 15 min later, transpupillary laser irradiation of branch retinal vein near the optic nerve head was performed. Irradiation energy density was 200 J / cm2. Histological analysis and immunohistochemistry of the retina was performed following 30 min, at days 1, 2, 3, 7, 14 and 30.Results. Maximum VEGF accumulation in photoinduced BRVO model was observed on day 2. From day 3, direct neovascularization was confirmed. VEGF levels were stably high throughout the follow-up to the day 30 inclusive.Conclusion. VEGF immune expression in the retina using the model of BRVO induced by photodynamic exposure was explored for the first time. These data can serve as the basis for future studies in order to define optimal anti-VEGF agent, its dosage and terms to manage this condition

Essential functions of RNA helicase Vasa in maintaining germline stem cells and piRNA-guided Stellate silencing in Drosophila spermatogenesis

DEAD-box RNA helicase Vasa is required for gonad development and fertility in multiple animals. Vasa is implicated in many crucial aspects of Drosophila oogenesis, including translation regulation, primordial germ cell specification, piRNA silencing of transposable elements, and maintenance of germline stem cells (GSCs). However, data about Vasa functions in Drosophila spermatogenesis remain controversial. Here we showed that loss-of-function vasa mutations led to failures of GSC maintenance in the testes, a severe loss of total germ cell content, and a cessation of male fertility over time. Defects in GSC maintenance in vasa mutant testes were not associated with an increasing frequency of programmed cell death, indicating that a premature loss of GSCs occurred via entering differentiation. We found that Vasa is implicated in the positive regulation of rhino expression both in the testes and ovaries. The introduction of a transgene copy of rhino, encoding a nuclear component of piRNA pathway machinery, in vasa mutant background allowed us to restore premeiotic stages of spermatogenesis, including the maintenance of GSCs and the development of spermatogonia and spermatocytes. However, piRNA-guided repression of Stellate genes in spermatocytes of vasa mutant testes with additional rhino copy was not restored, and male fertility was disrupted. Our study uncovered a novel mechanistic link involving Vasa and Rhino in a regulatory network that mediates GSC maintenance but is dispensable for the perfect biogenesis of Su(Ste) piRNAs in testes. Thus, we have shown that Vasa functions in spermatogenesis are essential at two distinct developmental stages: in GSCs for their maintenance and in spermatocytes for piRNA-mediated silencing of Stellate genes

AS RELAÇÕES DE GÊNERO NOS CARGOS DE GESTÃO DA FACULDADE CEARENSE (FAC)

A inserção da mulher no mundo do trabalho e as recorrentes lutas por direitos iguais (tais como voto, o acesso ao ensino superior, a produção acadêmica e a profissionalização), trouxeram à tona a discussão acerca das desigualdades entre homens e mulheres. A pesquisa se propôs a responder a seguinte pergunta: Quais são as relações de gênero presentes na gestão feminina e masculina? O presente trabalho teve como objetivo analisar as relações de gênero presentes nos cargos de coordenação da Faculdade Cearense (FAC). Dessa forma, têm-se como objetivos específicos: identificar o perfil dos/as gestores/as da faculdade; verificar a percepção dos coordenadores acerca das relações de gênero; identificar se existem diferenças entre a gestão feminina e a gestão masculina; compreender as relações de gênero existentes no âmbito organizacional. Através de entrevistas realizadas aos gestores e gestoras, como também por meio da análise do referencial teórico, apreendeu-se que as relações de gênero se manifestam no espaço organizacional das mais variadas formas, seja: na atuação dos/as gestores, no preconceito e discriminação enfrentados pelas mulheres, pelos papeis e atribuições diferenciados associados para cada sexo no espaço de trabalho, pela dificuldade das mulheres em conciliar a vida pessoal com a profissional, dentre outras

Macro-microscopic study of posterior vitreous detachment variants in an ex vivo experiment

Purpose. The key to understanding the development of any vitreoretinal pathology is a presence of a clear conception to possible variants of changes in the anatomical and topographic relationships of the posterior cortical layers of the vitreous body and the retinal internal limiting membrane (ILM) in a formation of posterior vitreous detachment (PVD).An original method of macro-microscopic examinations of anatomical objects proposed by professor V.P. Vorobyov, which includes investigations of morphological objects whose dimensions lie in the boundary area between macroscopic parameters studied by anatomists and microstructures studied by histologists, discover a new boundary area for the study of anatom ical structures.However, it has not been practically used in ophthalmology until now. The study of a process for changes in the vitreoretinal interface during the PVD occurrence is difficult due to a complexity of simulation, a possibility of visualization, and an absence of approved protocols for macro-microscopic research.Purpose. To study variants of anatomical and topographical changes in the vitreoretinal interface during the formation of induced PVD in ex vivo experiments using the method of macro-microscopic examination.Material and methods. The study was performed in 24 eyeballs of cadaver donors. To assess changes in the vitreoretinal interface in the process of PVD induction, an original method of dissection was used, that allows to isolate layer-by-layer the cortical layers of the vitreous body and the retinal ILM, with a possibility of further evaluation of changes in the vitreoretinal interface by the macro-microscopic examination. Salt barium sulfate suspension Video-contrast was used with the purpose to contrast vitreous fibers. Macroscopic investigation was carried out using the Topcon OMS-800 operating microscope with an indication from x8 to x21 magnification, microscopic changes were evaluated by the light microscopy method with x50, x100, x200, x400 x630 magnification using the Leica DM LB2 microscope with the subsequent photo r egistration.Results. During the macro-microscopic study, three variants of possible changes in the vitreoretinal interface during the development of induced PVD were revealed, which were interpreted as the normal (true) PVD and abnormal PVD, which occurred both with the formation (the variant A) of vitreoschisis zones (exfoliation of the cortical layers of the vitreous body) and with the zones of retinal ILM exfoliation (the variant B).Conclusion. The proposed method of macro-microscopic investigation of the vitreoretinal interface allows to dissect isolated sequentially layerby- layer the cortical layers of the vitreous body and the retinal ILM with subsequent fixation on a special substrate according to the original method and the possibility to carry out a histological section and its evaluation by the light m icroscopy method. The application of the developed method allows to accurately assess changes in the vitreoretinal interface on any isolated site of the vitreoretinal surface. The presented work demonstrates possibilities for the application of the method to detect variants of changes in the vitreoretinal interface within the formation of i nduced PVD

Дифференциальный подход к лечению пациентов с первичной открытоугольной глаукомой

PURPOSE: To evaluate Prolatan effectiveness in groups of patients with risk of glaucoma progression. METHODS: We used Moriscos-Green/Blank clinical and psychological tests-scales of compliance to assess 190 patients with primary open-angle glaucoma (POAG). We revealed 57 out of 190 POAG patients (30%) to be insufficiently committed to their treatment. Among them were 22 (38%) women and 35 (62%) men with mean age 64.4±2.5 years. 18 (32%) patients were diagnosed with glaucoma within the last month before admission, while 39 (68%) patients had progressive glaucoma. All patients underwent standard ophthalmic examination and additional Humphrey standard automated perimetry (threshold 30-2 strategy) at baseline and after 3 months. RESULTS: Statistically significant non-compliance factors were the following: age over 60, male gender, POAG duration from 3 to 10 years, comorbid pathology, regimens comprising a large number of drugs, mild glaucoma, cognitive impairment and financial difficulties, hindering the purchase of medicinal products. On the average, Prolatan decreased IOP level by 33%. By the end of the 3rd month our study revealed retinal light sensitivity increase in all sectors of the visual field from 0 to 30 degrees due to IOP stabilization. CONCLUSION: Prolatan increases adherence to treatment by the end of the 3rd month of follow-up, which is associated with a reduction in the number of instillations, no side effects after instillation, patients’ good health during the treatment course, reduction of treatment material costs. ЦЕЛЬ. Оценить эффективность препарата Пролатан в группах риска прогрессирования глаукомы. МЕТОДЫ. С помощью клинико-психологической тестовой методики — шкалы комплаентности Мориски – Грин проведена оценка комплаентности 190 пациентов с первичной открытоугольной глаукомой (ПОУГ). Из 190 обследованных пациентов с ПОУГ недостаточно приверженными лечению были 57 (30%) пациентов. Среди них было 22 (38%) женщины и 35 (62%) мужчин, средний возраст составил 64,4±2,5 года. Впервые выявленная глаукома в течение 1 месяца была у 18 (32%) пациентов, некомпенсированная глаукома — у 39 (68%) больных. Проводили стандартное офтальмологическое исследование, дополнительно — статическую компьютерную периметрию на компьютерном периметре Humphrey по пороговой стратегии 30-2 исходно и через 3 месяца. РЕЗУЛЬТАТЫ. Достоверными факторами нон-комплаенса у обследованных больных были: возраст старше 60 лет, мужской пол, длительность ПОУГ от 3 до 10 лет, наличие коморбидной патологии и большое количество лекарственных средств, которые вынужден применять пациент, начальная стадия глаукомы, наличие когнитивных нарушений, финансовые затруднения пациентов при приобретении лекарственных средств. Снижение внутриглазного давления (ВГД) в результате применения препарата Пролатан составило 33%. На фоне стабилизации ВГД к концу 3-го месяца выявлено увеличение показателей светочувствительности сетчатки по всем секторам поля зрения от 0 до 30°. ЗАКЛЮЧЕНИЕ. На фоне лечения препаратом Пролатан увеличивается приверженность лечению к концу 3-го месяца наблюдения, что связано со снижением количества инстилляций, отсутствием побочных эффектов после закапывания, хорошим самочувствием пациентов во время лечения, снижением материальных затрат на лечение.

Разработка техники трансплантации 3D-клетонных сфероидов ретинального пигментного эпителия в опыте на животных

Aim. This research is aimed to devise the technique for transplantation of 3D spheroids retinal pigment epithelium (RPE) in the experimental animal’s eyes (rabbits).Materials and methods. 3D spheroids of RPE for subsequent transplantation were created using agarose tablets (3D Petri Dishes, Microtissue, USA). The phenotype of the obtained cell cultures was studied by immunocytochemical tests (laser scanning confocal microscope “Fluo View FV10i”, Olympus, Japan). Vitrectomy - 2500 cuts per minute, vacuum 600 mm Hg (Alcon, Accurus, USA) was performed on all rabbits (n = 10). Then, we made retinotomy and injected spheroids in subretinal space (MicroDose injection kit 1 ml, Med One, USA). The following methods of control: ultrasound B-scan (Ultrasonic UD-6000, Tomey, Japan) and optical coherence tomography (OCT), (Askin Spectralis, Heidelberg engineering, Germany). Eyes were enucleated for histological examination on 7, 10, 14 and 20 days.Results. Immunocytochemical tests revealed preservation of the RPE epithelial phenotype in 3D spheroids. Clinical map was similar in all experimental animals - during the first 7 days after surgery we saw cystic edema and flat retinal detachment in the surgery area. As we observed, the retina was adjoining and retinal edema was decreasing. Also, on day 3, 7 and 10 on OCT we saw subretinal round conglomerates with a diameter of 60 to 80 µm - presumably RPE 3D spheroids. According to histological findings, there was observed adhesion of the RPE spheroids to the choroid with subsequent spreading and formation of new cell layer with the increase of observation periods.Conclusion. The proposed technology of cultivation of rabbit RPE with subsequent construction of 3D spheroids allows to preserve the epithelial phenotype of cells. The developed surgical technique of RPE transplantation is acceptable and can be used for further experimental studies to be implemented in clinical practice.Цель исследования. Разработка техники трансплантации SD-клеточных сфероидов ретинального пигментного эпителия (РПЭ) на глазах экспериментальных животных (кролики).Материалы и методы. SD-сфероиды РПЭ для последующей трансплантации создавали с использованием агарозных планшетов (3D Petri Dishes, Microtissue, США). Фенотип полученных клеточных культур исследовали с помощью иммуноцитохимического анализа (лазерный сканирующий конфокальный микроскоп «Fluo View FV10i», Olympus, Япония). Всем экспериментальным животным (кролики породы шиншилла, n = 10) выполняли витрэктомию - 2500 резов в минуту, вакуум 600 мм рт. ст. (Alcon, Accurus, США), ретинотомию и субретинально вводили сфероиды РПЭ (MicroDose injection kit 1 ml, Med One, США). Методы послеоперационного контроля: ультразвуковое В-сканирование глаза (Ultrasonic UD-6000, Tomey, Япония) и оптическая когерентная томография - ОКТ (Askin Spectralis, Heidelberg engineering, Германия). Глазные яблоки энуклеировали на 7, 10, 14, 20-е сутки для последующего гистологического исследования.Результаты. Иммуноцитохимическое окрашивание выявило сохранение фенотипа РПЭ в форме 3D-сфе-роидов. В послеоперационном периоде у всех экспериментальных животных по данным ультразвукового В-сканирования и ОКТ отмечалась схожая клиническая картина: отек и плоская отслойка сетчатки в зоне оперативного вмешательства. По мере наблюдения сетчатка прилегала и отек сетчатки уменьшался. Также, по данным ОКТ, субретинально обнаруживались округлые конгломераты диаметром от 60 до 80 мкм - предположительно 3D-сфероиды РПЭ. По данным гистологического исследования отмечалась адгезия сфероидов РПЭ к сосудистой оболочке с последующим распластыванием и образованием нового клеточного слоя по мере увеличения сроков наблюдения.Заключение. Предложенная технология культивирования кроличьего РПЭ с последующим конструированием 3D-сфероидов позволяет сохранить эпителиальный фенотип клеток. Разработанная хирургическая техника трансплантации РПЭ является приемлемой и может использоваться для дальнейших экспериментальных исследований с целью внедрения в клиническую практику

Trans-inactivation: Repression in a wrong place

Trans-inactivation is the repression of genes on a normal chromosome under the influence of a rearranged homologous chromosome demonstrating the position effect variegation (PEV). This phenomenon was studied in detail on the example of brownDominant allele causing the repression of wild-type brown gene on the opposite chromosome. We have investigated another trans-inactivation-inducing chromosome rearrangement, In(2)A4 inversion. In both cases, brownDominant and In(2)A4, the repression seems to be the result of dragging of the euchromatic region of the normal chromosome into the heterochromatic environment. It was found that cis-inactivation (classical PEV) and trans-inactivation show different patterns of distribution along the chromosome and respond differently to PEV modifying genes. It appears that the causative mechanism of trans-inactivation is de novo heterochromatin assembly on euchromatic sequences dragged into the heterochromatic nuclear compartment. Trans-inactivation turns out to be the result of a combination of heterochromatin-induced position effect and the somatic interphase chromosome pairing that is widespread in Diptera