240 research outputs found
In vitro evaluation of marketed antimalarial chloroquine phosphate tablets
Background & objectives: The aim of the present study is to investigate the physicochemicalequivalence of seven brands of tablets containing chloroquine phosphate, an antimalarial purchasedfrom different retail pharmacy outlets.Methods: The quality and physicochemical equivalence of seven different brands of chloroquinephosphate tablets were assessed. The assessment included the evaluation of uniformity of weight,friability, crushing strength, disintegration and dissolution tests as well as chemical assay of thetablets.Results: All the seven brands of the tablets passed the British Pharmacopoeia (BP) standards foruniformity of weight, disintegration and crushing strength. One of seven brands failed the friabilitytest. One of the brands did not comply with the standard assay of content of active ingredients.Dissolution test passes the pharmacopoeial standards for chloroquine phosphate tablets. There wereno significant differences in the amounts of chloroquine phosphate released from the different brands.Interpretation & conclusion: Out of the seven brands of anti-malarial chloroquine phosphate tabletsonly one brand fails to meet BP quality specifications which shows constant market monitoring ofnew products to ascertain their equivalency to pharmacopoeial standards
К решению неоднородных уравнений в частных производных с правой частью, заданной на сетке
An algorithm is proposed for obtaining solutions of partial differential equations with right-hand side defined on the grid {xµ1 , xµ2 , . . ., xµn}, (µ = 1, 2, . . ., N): fµ = f (xµ1 , xµ2 , . . ., xµn). Here n is the number of independent variables in the original partial differential equation, N is the number of rows in the grid for the right-hand side, f = f (x1, x2, . . ., xn) is the right-hand of the original equation. The algorithm implements a reduction of the original equation to a system of ordinary differential equations (ODE system) with initial conditions at each grid point and includes the following sequence of actions. We seek a solution to the original equation, depending on one independent variable. The original equation is associated with a certain system of relations containing arbitrary functions and including the partial differential equation of the first order. For an equation of the first order, an extended system of equations of characteristics is written. Adding to it the remaining relations containing arbitrary functions, and demanding that these relations be the first integrals of the extended system of equations of characteristics, we arrive at the desired ODE system, completing the reduction. The proposed algorithm allows at each grid point to find a solution of the original partial differential equation that satisfies the given initial and boundary conditions. The algorithm is used to obtain solutions of the Poisson equation and the equation of unsteady axisymmetric filtering at the points of the grid on which the right-hand sides of the corresponding equations are given. © 2021 Udmurt State University. All rights reserved
On one approach to solving nonhomogeneous partial differential equations
An approach to obtaining exact solutions for nonhomogeneous partial differential equations (PDEs) is suggested. It is shown that if the right-hand side of the equation specifies the level surface of a solution of the equation, then, in this approach, the search of solutions of considered nonhomogeneous differential equations is reduced to solving ordinary differential equation (ODE). Otherwise, searching for solutions of the equation leads to solving the system of ODEs. Obtaining a system of ODEs relies on the presence of the first derivatives of the sought function in the equation under consideration. For PDEs, which do not explicitly contain first derivatives of the sought function, substitution providing such terms in the equation is proposed. In order to reduce the original equation containing the first derivative of the sought function to the system of ODEs, the associated system of two PDEs is considered. The first equation of the system contains in the left-hand side only first order partial derivatives, selected from the original equation, and in the right-hand side it contains an arbitrary function, the argument of which is the sought unknown function. The second equation contains terms of the original equation that are not included in the first equation of the system and the right-hand side of the first equation in the system created. Solving the original equation is reduced to finding the solutions of the first equation of the resulting system of equations, which turns the second equation of the system into identity. It has been possible to find such solution using extended system of equations for characteristics of the first equation and the arbitrariness in the choice of function from the right-hand side of the equation. The described approach is applied to obtain some exact solutions of the Poisson equation, Monge-Ampere equation and convection-diffusion equation
T-Cadherin Stimulates Melanoma Cell Proliferation and Mesenchymal Stromal Cell Recruitment, but Inhibits Angiogenesis in a Mouse Melanoma Model
Cholinergic stimulation blocks endothelial cell activation and leukocyte recruitment during inflammation
Endothelial cell activation plays a critical role in regulating leukocyte recruitment during inflammation and infection. Based on recent studies showing that acetylcholine and other cholinergic mediators suppress the production of proinflammatory cytokines via the α7 nicotinic acetylcholine receptor (α7 nAChR) expressed by macrophages and our observations that human microvascular endothelial cells express the α7 nAChR, we examined the effect of cholinergic stimulation on endothelial cell activation in vitro and in vivo. Using the Shwartzman reaction, we observed that nicotine (2 mg/kg) and the novel cholinergic agent CAP55 (12 mg/kg) inhibit endothelial cell adhesion molecule expression. Using endothelial cell cultures, we observed the direct inhibitory effects of acetylcholine and cholinergic agents on tumor necrosis factor (TNF)-induced endothelial cell activation. Mecamylamine, an nAChR antagonist, reversed the inhibition of endothelial cell activation by both cholinergic agonists, confirming the antiinflammatory role of the nAChR cholinergic pathway. In vitro mechanistic studies revealed that nicotine blocked TNF-induced nuclear factor–κB nuclear entry in an inhibitor κB (IκB)α- and IκBɛ-dependent manner. Finally, with the carrageenan air pouch model, both vagus nerve stimulation and cholinergic agonists significantly blocked leukocyte migration in vivo. These findings identify the endothelium, a key regulator of leukocyte trafficking during inflammation, as a target of anti-inflammatory cholinergic mediators
Adipose-Derived Stem Cells Stimulate Regeneration of Peripheral Nerves: BDNF Secreted by These Cells Promotes Nerve Healing and Axon Growth De Novo
Transplantation of adipose-derived mesenchymal stem cells (ASCs) induces tissue regeneration by accelerating the growth of blood vessels and nerve. However, mechanisms by which they accelerate the growth of nerve fibers are only partially understood. We used transplantation of ASCs with subcutaneous matrigel implants (well-known in vivo model of angiogenesis) and model of mice limb reinnervation to check the influence of ASC on nerve growth. Here we show that ASCs stimulate the regeneration of nerves in innervated mice's limbs and induce axon growth in subcutaneous matrigel implants. To investigate the mechanism of this action we analyzed different properties of these cells and showed that they express numerous genes of neurotrophins and extracellular matrix proteins required for the nerve growth and myelination. Induction of neural differentiation of ASCs enhances production of brain-derived neurotrophic factor (BDNF) as well as ability of these cells to induce nerve fiber growth. BDNF neutralizing antibodies abrogated the stimulatory effects of ASCs on the growth of nerve sprouts. These data suggest that ASCs induce nerve repair and growth via BDNF production. This stimulatory effect can be further enhanced by culturing the cells in neural differentiation medium prior to transplantation
Assessment of the risks of changes in brachiocephalic vessels according to ultrasound examination of patients with obstructive sleep apnea
Introduction. In the medical literature, there is not enough work on the impact of obstructive sleep apnea (OSA) on the development of atherosclerosis of the brachiocephalic arteries and venous dysgemenia. For the purpose of early diagnosis of vascular complications, further study of extracranial vessels in patients with OSA is necessary.Aim. To study the chances of changes in brachiocephalic vessels by ultrasound examination in patients with obstructive sleep apnea.Materials and methods. A survey was carried out of 88 patients. The results of anthropompetry, polysomnography and ultrasound examination of brachiocephalic vessels were evaluated.Results and discussion. New data were obtained on the severity of macroangiopathy, an increase in the peak systolic blood flow velocity in the internal jugular veins, and an increase in the diameters of the vertebral veins in patients with sleep apnea. It was also found that in patients with OSA, the chances of having a wide diameter of the common carotid artery (CCA) on both sides and the internal carotid artery on the left are more than 3 times higher, the probability of thickening of the intima-media complex in the area of the CCA and its bifurcation is more than on the left 3.5 times and the chances of macroangiopathy are 3 times higher in comparison with the examined patients without apnea.Conclusion. Timely assessment of the entire spectrum of pathological changes in the brachiocephalic vessels in patients with OSA will make it possible to diagnose early signs of atherosclerotic lesions of the arteries, venous dysfunction at the extracranial level
Human Capital of the Far East of Russia: Problems and Prospects
The article presents the problems and trends in the development of the Far Eastern territories of the Russian Federation associated with a high level of migration and loss of human capital in the region. Human capital is the basis for the development of the economy and industry in any region. For the Far East of Russia, issues related to human capital are of particular importance, since the region faces the task of industrial competition with the nearest Asian economies (China, Japan, South Korea), and the transition from resource trade to an innovative economy requires highly qualified personnel, which must be attracted and consolidated in the region. The article deals with special legislative acts and programs (in particular, the intermediate results of the program "Far Eastern hectare") aimed at the development of the Far East. It is shown that the constantly continuing outflow of the local population, consisting mainly of the qualified part of the labor potential of the district in active working age, jeopardizes the implementation of the planned programs. The article analyzes the results of the author's study aimed at identifying the opinions and assessments of experts on the demographic situation and the causes of migration outflow of the population in the Far Eastern Federal district (Primorsky Krai). The data obtained show that, according to experts, the reasons for not decreasing migration from the region are: the high cost of housing, extremely low infrastructure, relatively low wages, high prices for goods and products compared to the European part of the country; most of the specialists surveyed believe that first of all the main measure of securing people in the region can be the provision of housing (housing in employment, preferential types of mortgages, assistance in housing construction). It is emphasized that the state policy in the region should be aimed at the development, attraction and preservation of human capital of the regional community.В статье представлены проблемы и тенденции развития дальневосточных территорий Российской Федерации, связанные с высоким уровнем миграции населения и потерей регионом человеческого капитала. Человеческий капитал составляет основу для развития экономики и промышленности любого региона. Для Дальнего Востока России вопросы, связанные с человеческим капиталом приобретают особую важность, поскольку перед регионом стоит задача промышленной конкуренции с ближайшими азиатскими экономиками (Китай, Япония, Южная Корея), а для перехода от торговли ресурсами к инновационной экономике требуются высококвалифицированные кадры, которые необходимо привлечь и закрепить в регионе. В статье рассматриваются специальные законодательные акты и программы (в частности, промежуточные результаты реализации программы «Дальневосточный гектар»), ориентированные на развитие Дальнего Востока. Показано, что постоянно сохраняющийся отток местного населения, состоящий в основном из квалифицированной части трудового потенциала округа в активном трудовом возрасте, ставит под угрозу реализацию намеченных программ. Анализируются результаты авторского исследования, направленного на выявление мнений и оценок экспертов о демографической ситуации и причинах миграционного оттока населения в ДФО (на примере Приморского края). Полученные данные показывают, что, по мнению экспертов, причинами, не снижающейся миграции из региона, выступают: высокая стоимость жилья, крайне низко развитая инфраструктура, относительно низкий уровень заработной платы, высокие цены на товары и продукты по сравнению с европейской частью страны; большинство опрошенных специалистов, считают, что в первую очередь главной мерой закрепления людей в регионе может стать обеспечение населения жильем (предоставление жилья при трудоустройстве, льготные виды ипотеки, помощь в строительстве жилья). Подчеркивается, что государственная политика в регионе должна быть направлена на развитие, привлечение и сохранение человеческого капитала регионального сообщества.Исследование выполнено при финансовой поддержке РФФИ в рамках научного проекта № 19-011-00768
Comparison study of preferential oxidation of CO over nanocrystalline Cu/CeO2 catalysts synthesized by different preparation methods
121-126Preferential oxidation of carbon monoxide in presence of excess hydrogen is a promising alternative to restrict the CO
deposition in the Pt-anode in the practical polymer electrolyte membrane fuel cell application. In the present work,
nanocrystalline copper-ceria catalysts have been synthesized by hydrothermal method, wet impregnation method and urea
nitrate combustion method. Their characterizations have been carried out by using X-ray diffraction, transmission electron
microscopy, X . ray photoelectron spectroscopy- It has been found that Cu2+ replaced Ce4+ in cerium oxide, creating oxygen
vacancy. The formation of more nano-sized CeO2 leads to more oxygen vacancies in CeO2 through the formation of
interfacial Cu1+ ions, which also enhances the CO oxidation activity. Among the synthesized Cu-CeO2 catalysts, the catalyst
prepared by hydrothermal method have shown both CO conversion andC O2 selectivity as 100% towards CO oxidation at
373 K in the presence of excess H2 making this catalyst viable for practical fuel cell application.
Multiparametric determination of genes and their point mutations for identification of beta-lactamases
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