Structural transformations during swelling of polycomplex matrices based on countercharged (meth)acrylate copolymers (Eudragit® EPO/Eudragit® L 100-55)

With a view to the application in oral controlled drug delivery systems (DDS), the design of new interpolyelectrolyte complexes (IPECs) between countercharged types of Eudragit® EPO (EPO) and Eudragit® L 100-55 (L100-55) was investigated. The formation and composition of four new IPECs between EPO and L100-55 were established by elementary analysis. The structure of the synthesized IPEC was investigated using FTIR spectroscopy and modulated-temperature differential scanning calorimetry. The binding ratio of a unit molecule of EPO with L100-55 was found to range between 1:2.75 (Z = 0.36) and 1:0.55 (Z = 1.81) while increasing the pH value from 5.5 to 7.0. As a result of electrostatic interaction between the copolymer chains, the glass transition temperature of the IPEC increased significantly. A large pH-sensitive swelling behavior was observed for different structures of the IPECs. The outcome of swelling and diclofenac sodium release from the polycomplex matrices confirm that they have great potential to be used as a controlled DDS in specified regions of gastrointestinal tract. © 2010 Wiley-Liss, Inc. and the American Pharmacists Association

Structural and energetic approach in controlling the surface strength of materials during friction

From the standpoint of the structural-energetic theory of friction and wear, general principles of managing the surface strength of materials during friction are proposed. The fundamental principles of tribology and the conditions for the formation of dissipative self-organizing secondary structures are considered. The role of the kinetic phase transition in the energy balance of processes in the zone of frictional contact is determine

Уточнение гемодинамической значимости стенотического поражения экстракраниальных отделов каротидных артерий по данным ультразвукового исследования внутренней яремной вены

Aim. To study changes in the size and linear velocities of the blood flow of internal jugular veins in patients with high degree stenosis of the extracranial carotid artery.Methods. The study included 28 patients: 14 patients with high degree stenoses of the internal carotid arteries (70% and more by NASCET criteria) constituted group 1, 14 patients with “small” stenoses of the ICA (less than 30%) – group 2. The state of blood flow in the extracranial sections of the main arteries of the head were evaluated using ultrasound.Results. When studying the features of venous blood flow, the following was found: in the group with unilateral hemodynamically significant stenosis, in contrast to the group of patients with “small” stenoses, the venous pressure measured on the arm was statistically significantly lower, and therefore the calculated central venous pressure, while the linear velocities of the peaks S and T were statistically significantly higher by 1 the group on the side of hemodynamically significant stenosis. On the side of contralateral stenosis in group 1, there was statistically significantly less area of VAV, and the ratio S1/S2, than in patients of group 2. Intra-group analysis revealed a statistically significant difference in almost all indicators in patients with hemodynamically significant stenosis compared with the contralateral side: the diameters of the vein and its area were larger, and the linear rates of the A, S and T peaks were higher. Whereas there were no statistically significant differences in the group of “small” stenoses.Conclusion. Changes in venous blood flow in the jugular veins are interrelated with the development of high degree carotid stenosis and have diagnostic significance, can be used as an additional sign of the hemodynamic significance of carotid stenosis.Цель исследования: изучение изменений размеров и линейных скоростей кровотока внутренних яремных вен (ВЯВ) у пациентов со стенозом “высокой” степени экстракраниальных отделов внутренних сонных артерий (ВСА).Материал и методы. В исследование было включено 28 пациентов: 14 пациентов со стенозами “высокой” степени ВСА (более 70% по критериям NASCET) составили 1-ю (основную) группу, 14 пациентов с “малыми” стенозами ВСА (менее 30%) – 2-ю (контрольную) группу. Состояние кровотока в экстракраниальных отделах магистральных артерий головы оценивали с использованием ультразвукового исследования.Результаты. При изучении особенностей венозного кровотока было установлено следующее: в группе со стенозами “высокой” степени в отличие от группы пациентов с “малыми” стенозами статистически значимо было ниже венозное давление, измеренное на руке, а следовательно, и расчетное центральное венозное давление, тогда как линейные скорости пиков S и T были статистически значимо выше в 1-й группе на стороне гемодинамически значимого стеноза. На стороне, контралатеральной стенозу, в 1-й группе статистически значимо были меньше площадь ВЯВ и отношение S1/S2, чем у пациентов 2-й группы. При внутригрупповом анализе у пациентов с гемодинамически значимым стенозом выявлена статистически значимая разница практически всех показателей по сравнению с контралатеральной стороной: диаметры вены и ее площадь были больше, а линейные показатели скоростей пиков A, S и T выше, тогда как в группе “малых” стенозов статистически значимых различий не получено.Заключение. Изменения размеров и венозного кровотока ВЯВ взаимосвязаны с развитием стенозов ВСА “высокой” степени, обладают важными диагностическими особенностями и могут быть использованы в качестве дополнительного признака гемодинамической значимости каротидного стеноза

МАГНИТНО-РЕЗОНАНСНАЯ ТОМОГРАФИЯ С КОНТРАСТНЫМ УСИЛЕНИЕМ КАК МЕТОД ВИЗУАЛИЗАЦИИ АТЕРОСКЛЕРОТИЧЕСКОГО ПОРАЖЕНИЯ СТЕНКИ АОРТЫ

The article describes patterns of paramagnetic contrast enhanced MR tomographic imaging of atherosclerotic lesions of aorta in patients with extensive atherosclerosis and previous acute myocardial infarction.The purpose. We have analyzed MR tomographic imaging features of atherosclerotic lesions of the aorta, with a paramagnetic contrast enhancement, in patients with extensive atherosclerosis and old acute myocardial infarction (AMI).Materials and methods. The patients population comprised 24 patients with multiple atherosclerosis and old transmural AMI of the left ventricle. As control group eight patients with tumor pathology of the thorax were employed, without evidence of clinically significant atherosclerosis, of the same age range. All patients underwent contrast-enhanced study (paramagnetic in standard dose of 0,1 mmol / kg BW) and index of enhancement (IE) of T1-weighted images was calculated as the ratio of intensities over the aortic wall on contrast and initial MRI studies.Results and discussion. In patients with extensive atherosclerosis and old AMI IE of the atherosclerotic lesions in the aortic wall in all cases was over 1,14 (mean 1,19±0,06), far more than increasing of intensity in the control group. Types of accumulation of contrast paramagnetic was assigned as a local or diffuse accumulation syndrome, depending on the length and circularity of the lesions. In the control group no significant accumulation of contrast paramagnetic material in the aortic wall was observed, IE did not exceed 1.04 (mean 1,01±0,02).Conclusion. Contrast-enhanced MRI allows to visually and quantitatively assess pathology of aortic wall in atherosclerosis.В статье представлена картина МР-томографической визуализации атеросклеротических изменений аорты у пациентов с распространенным атеросклерозом и перенесенным острым инфарктом миокарда при контрастировании парамагнетиком.Цель. Изучить картину МР-томографической визуализации атеросклеротических поражений аорты при парамагнитном контрастировании у пациентов с распространенным атеросклерозом и перенесенным острым инфарктом миокарда (ОИМ).Материалы и методы. В исследование были включены 24 пациента с распространенным атеросклерозом и перенесенным трансмуральным ОИМ левого желудочка. В качестве контрольных обследованных в исследование включены восемь пациентов с опухолевой патологией органов грудной клетки (ОГК) без признаков клинически значимого атеросклероза того же возрастного диапазона. Всем пациентам проведено контрастированое исследование с введением парамагнетика в стандартной дозе 0,1 ммоль/1 кг массы тела и рассчитан индекс усиления Т1-взв. изображения как отношение интенсивности области стенки аорты на контрастированном и исходном МРТ-исследовании.Результаты. У пациентов с распространенным атеросклерозом и перенесенным ОИМ наблюдалось достоверно превосходящее показатели контрольных лиц усиление интенсивности сигнала в атеросклеротически измененной стенке аорты при введении контраста-парамагнетика, значение ИУ во всех случаях было больше 1,14 (среднее значение – 1,19±0,06). Характер накопления контраста-парамагнетика в зависимости от протяженности и циркулярности поражения визуализируется как локально-очаговый либо диффузно-распространенный тип аккумуляции. В контрольной группе было отмечено отсутствие значимого накопления контраста парамагнетика в стенке аорты, ИУ не превышал 1,04 (среднее значение – 1,01±0,02).Заключение. Контрастированная МРТ позволяет визуально и количественно оценить патологическое поражение аортальной стенки при атеросклерозе

[FEATURES OF CHANGES IN CEREBRAL BLOOD CIRCULATION IN CHILDREN WITH CEREBRAL PALSY FOR THE IMPACT OF BOBATH THERAPY]

Among the existing innovative and effective methods of physical rehabilitation, Bobaththerapy is noted. However, scientifically substantiated results, which could indicate its impact on the state of children with Central Nervous System deficiency is very few. A total Bobath-therapy course was conducted of 72 procedures, 35 children (4.3 ± 1.0 years old) patients with Cerebral Palsy undergo a half-year were treated with Bobath-therapy. At the beginning and at the end of the physical rehabilitation course, all children underwent a comprehensive examination, which included diagnostics of physical development, psychophysical state, motor function, and cerebral blood flow using the method of transcranial dopplerography (TCDG). According to the assessment of children physical development, there was a significant increase in body length (p <0.05), body length sitting (p <0.01), body weight (p <0.01) and chest coverage (p <0.05), but the mobility of the chest has not increased. According to the scale of motor function assessment, the increase was more than doubled, the number of children who were able to sit on the floor, to sit down and to walk without additional means of transport has changed from 22.9% to 48.6%. At the same time, children with total limitation of motor function and the inability to move independently, at the end of the course, have not been observed at all. According to the Munich Diagnostics, the positive trend has been related to the greater degree of motor abilities of the child, namely, the aperture and small motility, however, according to the parameters of "speech comprehension" and "psychological age", the inconsistency with age norms increased insignificantly. According to the data of the TCDG of the brain vessels, it has shown that the usage of the Bobat method in the course of physical rehabilitation of children with Cerebral Palsy significantly has improves cerebrovascular circulation, which is reflected in the normalization of blood flow parameters in the basins of the external and internal carotid arteries, the anterior, middle and posterior cerebral arteries, extracranial and intracranial segments the vertebral artery, which reaches the normative values in 62.7-97.1% of children. In this case, the growth of normative variants varies from 8.6% for the right internal carotid artery to 20.0% in cases for the extracranial spine of the left arterial region. At the end of the rehabilitation course there is a disappearance of circulatory in the segments of the vertebral artery, as well as excessive blood flow disorders in the direct venous sinus

A COMPARATIVE STUDY OF DRUG RELEASE FROM POLYCOMPLEX MATRICES IN STANDARD AND BIORELEVANT MEDIA USING USP III AND USP IV APPARATUS

The results of Indomethacin release from the oral drug delivery systems based on interpolymer complexes with Eudragit® copolymers are presented. The release assessment was performed by two methods - flow-through cell (USP IV Apparatus) and the reciprocating cylinder (USP III Apparatus) in standard buffer solutions and biorelevant media. The release of indomethacin can be described as "intestinal" type. According to the results Indomethacin was released faster using USP III Apparatus due to stress-effect on the erosion type matrices

THE FEATURES OF THE PREDICTIVE DISSOLUTION TESTING (REVIEW)

Dissolution test plays an important role at different levels of the development and manufacturing drugs as one of the major quality control tools and an integral part of In vitro tests in the study of drug release from the developed dosage forms. Article describes the basic parameters that should be considered in predictive dissolution tests, such as the selection criteria and the composition of biorelevant dissolution media, fluid dynamics, volume and transfer of the dissolution media

Optimization of apple juice dosage in the recipe of bakery products

Research on the development of bakery products of high nutritional value are conducted in FSBEI HE «Saratov State Agrarian University named after N.I. Vavilov». Improving the nutritional and biological value of bakery products remains an urgent task. One way to solve it is to use natural food fortifiers. Apple juice is one of the most affordable for the residents of Russia due to its low price and popularity of apples. It has a great advantage over others, as it contains a rich set of minerals and vitamins, enzymes, organic acids. The quality, structural, mechanical and rheological properties of bakery products depend on the amount of the additive. In the presented work the effect of the dosage of apple juice of the «Simirenko» apple variety on the quality of wheat semi-finished products and finished products has been studied. To determine the optimal dosage of apple juice, semi-finished products and finished products have been analyzed according to the following indicators: effective dough viscosity, humidity, porosity, hardness, color of finished bakery products. For the integrated assessment of the capabilities of the compared indicators, a mathematical apparatus has been used based on the basis of generalized desirability function of Harrington, which allows to obtain a relatively accurate assessment of the effectiveness in the form of a specific number that can be used in further analysis of technological processes. It’s been found that the optimal dosage for baked goods with the addition of apple juice is 30% apple juice to the weight of the liquid

Bread production technology modelling using hop starter in ovens of various types

The article studies the processes of structure formation of baked dough pieces using wheat and hop starters and changes in the properties of finished products and semi-finished products depending on the baking methods. A whole complex of physical, chemical and biochemical processes takes place in the dough piece during baking under the influence of heat and moisture, which causes considerable changes in the bread dough. These processes cause changes in the baked dough piece, that cause turning the dough into bread. Duration and intensity of the processes occurring on the surface and in the inner layers of the dough piece during baking depend on the temperature. Therefore, creation of optimal modes of heating the baked dough piece at various stages allows you to get products of the required quality. To simulate the processes of crumb formation, changes in temperature inside the dough piece of baking, and specific volume over time with different methods of dough and baking, regression models were used, that take into account the influence of qualitative factors. Each qualitative factor having two grades was replaced by one binary variable. The solution of a multicriteria optimization problem showed that the studied indicators reach the optimal values when baking in an air-o-steam and preparing a dough using hop starter