Effect of mechanical activation on the composition if mineral components in humic acids isolated from carbons

It is shown that the mechanical activation of oxidized and brown coals is accompanied by an increase in the yield of humic acids and in their content of functional groups. It was demonstrated by atomic-emission spectroscopy that, under a high-intensity mechanical treatment, mineral elements are redistributed in the coal substance and incorporated into the structure of humic acids

СРАВНЕНИЕ ТОЧНОСТИ МЕТОДА АБСОЛЮТНОЙ ГРАДУИРОВКИ И МОДИФИЦИРОВАННОГО МЕТОДА ПОСЛЕДОВАТЕЛЬНЫХ СТАНДАРТНЫХ ДОБАВОК НА ПРИМЕРЕ ОПРЕДЕЛЕНИЯ 3-(2,2,2-ТРИ¬МЕТИЛ¬ГИДРАЗИНИЙ)¬ПРОПИОНОВОЙ КИСЛОТЫ В МОЧЕ В УСЛОВИЯХ НЕЛИНЕЙНОСТИ ДЕТЕКТИРОВАНИЯ (ЭЛ

Contemporary determining of pharmaceuticals in biological liquids for the pur­poses of phar­maco­kine­tic studies and therapeutic drug monitoring implies the use of high-per­formance liquid chromatography coupled with mass spectrometry (LC-MS) with electrospray as a method of ionization. However, this techni­que is cha­rac­terized by a rather narrow linear detection range. It causes the restric­tions in quan­titation of analytes by method of absolute calibration.On the example of the determination of 3-(2,2,2-trimethylhydrazinium) propio­nate (THP) in urine it is shown that the method of successive standard additi­ons provides more precise results comparing with those obtained with non-linear absolu­te calib­ration at the same levels of analyte concentrations. Its principal fea­ture is the need to extrapolate the results to an infinite value of ad­dition.Keywords: 3-(2,2,2-trimethylhydrazinium) propionate, LC-MS, detection non­­­linearity, successive standard addition, non-linear absolute calibration(Russian)DOI: http://dx.doi.org/10.15826/analitika.2013.17.2.008Тatiana Е. Morozova1, Georgy V. Karakashev1, Pavel N. Sorokoumov1,Elena I. Savelieva1, Igor G. Zenkevich2 1Research Institute of Hygiene, Occupational Pathology and Human Ecology, Russian Federation, Leningrad Region., Vsevolozhsk district, town Kuzmolovsky, Art. Kapitolovo2St. Petersburg State University, Russian Federation, Saint-Petersburg На примере ВЭЖХ-МС определения 3-(2,2,2-триметилгидразиний)про­пионовой кис­лоты (THP) в моче (способ ионизации электроспрей) показано, что применение модифицированного метода последовательных стан­дарт­ных до­бавок, включающего экстраполяцию результатов на бесконечно большую ве­личину добавки, позволяет получать результаты, характеризующиеся большей точнос­тью, чем при использовании нелинейной абсолютной градуиров­ки.Ключевые слова: 3-(2,2,2-триметилгидразиний)пропионовая кислота, ВЭЖХ-МС ана­лиз, нелинейность детектирования, метод последовательных стандартных доба­вок, нелинейная абсолютная градуировкаDOI: http://dx.doi.org/10.15826/analitika.2013.17.2.00

Structure-Dependent Mechanism of Organophosphate Release from Albumin and Butyrylcholinesterase Adducts When Exposed to Fluoride Ion: A Comprehensive In Silico Study

The most favorable targets for retrospectively determining human exposure to organophosphorus pesticides, insecticides, retardants, and other industrial organophosphates (OPs) are adducts of OPs with blood plasma butyrylcholinesterase (BChE) and human serum albumin (HSA). One of the methods for determining OP exposure is the reactivation of modified BChE using a concentrated solution of KF in an acidic medium. It is known that under the action of fluoride ion, OPs or their fluoroanhydrides can be released not only from BChE adducts but also from the adducts with albumin; however, the contribution of albumin to the total pool of released OPs after plasma treatment with KF has not yet been studied. The efficiency of OP release can be affected by many factors associated with the experimental technique, but first, the structure of the adduct must be taken into account. We report a comparative analysis of the structure and conformation of organophosphorus adducts on HSA and BChE using molecular modeling methods and the mechanism of OP release after fluoride ion exposure. The conformational analysis of the organophosphorus adducts on HSA and BChE was performed, and the interaction of fluoride ions with modified proteins was studied by molecular dynamics simulation. The geometric and energy characteristics of the studied adducts and their complexes with fluoride ion were calculated using molecular mechanics and semiempirical approaches. The structural features of modified HSA and BChE that can affect the efficiency of OP release after fluoride ion exposure were revealed. Using the proposed approach, the expediency of using KF for establishing exposure to different OPs, depending on their structure, can be assessed

Development of Composition and Technology of Combination Drug with Neurally Mediated Action «Memofit»

Aim. The aim of this work is to develop composition of combination drug in the form of hard-gelatin capsules «Memofit», determine technological and microbiological parameters of intermediate products and ready medicinal product and develop of manufacturing process for capsules «Memofit».Methods of the research. Investigations presented in the article were performed in accordance with the procedures described by the State Pharmacopoeia of Ukraine (SPh Ukraine).The results of the research. Necessity of the development of dietary supplement to provide special dietary properties for the purpose of regulation of functions and systems of the organism within the physiologically normal states under the nervous system dysfunction was substantiated. Results of the study of pharmaco-technological and microbiological parameters of dry extracts that are included as a compound of hard-gelatin capsules «Memofit» were presented. Optimal technological parameters for manufacturing process of capsules «Memofit» were proposed. Results of mass balance for a batch of capsules «Memofit» proved rationality of selected manufacturing process were given. Technology of manufacturing process of capsules «Memofit» was introduced into the production on the TOV “DZ “GNCLS”.Conclusions. Possibility of the development of solid formulations in the form of capsules was established based on the obtained experimental findings of the determination of pharmaco-technological and microbiological parameters of dry extracts. It was shown that capsules «Memofit» are used in dietary food ration as additional source of biologically active substances for promoting normalization of brain function and sleep, improvement of attentiveness. This preparation has general tonic properties and improves mental and physical efficiency. Manufacturing process and process flow chart for this medication was substantiate

Heterogeneity of circulating tumor cells in neoadjuvant chemotherapy of breast cancer

The biological properties of circulating tumor cells (CTCs), and their dynamics during neoadjuvant chemotherapy are important, both for disease progression prediction and therapeutic target determination, with the aim of preventing disease progression. The aim of our study was to estimate of different CTC subsets in breast cancer during the NACT (neoadjuvant chemotherapy). The prospective study includes 27 patients with invasive breast cancer, T2-4N0-3M0, aged 32 to 60 years. Venous heparinized blood samples, taken before and after biopsy, after each courses of chemotherapy (on days 3-7), and before surgical intervention, served as the material for this study. Different subsets of circulating tumor cells were determined on the basis of the expression of EpCAM, CD45, CD44, CD24, and N-Cadherin using flow cytometry. As the result of this study, it has been observed that significant changes in the quantity of the different subsets of circulating tumor cells in patients' blood were observed after carrying out the 3rd course of NACT. NACT causes significant changes in the quantity of six CTC subsets, with various combinations of stemness and epithelial-mesenchymal transition (EMT) properties

Effect of mechanical activation on the composition if mineral components in humic acids isolated from carbons

It is shown that the mechanical activation of oxidized and brown coals is accompanied by an increase in the yield of humic acids and in their content of functional groups. It was demonstrated by atomic-emission spectroscopy that, under a high-intensity mechanical treatment, mineral elements are redistributed in the coal substance and incorporated into the structure of humic acids

Optical Spectral Approach to Breast Tissue Oxygen Saturation Analysis for Mastectomy Perioperative Control

The purpose of our research is to study the ability of the developed method of hemoglobin detection, based on the fiber-optic spectral analysis in visible region, to determine the level of blood supply to breast tissues before surgical treatment, intraoperatively and during observation of the patient in the postoperative period, when breast tissue is healing. The significant effect of subcutaneous adipose tissue on the shape of diffuse reflectance spectra due to scattering leads to a decrease in the accuracy of determining hemoglobin oxygen saturation and hemoglobin concentration from them. The variability of the subcutaneous adipose tissue layer is quite high, which also leads to a high variability of the spectra within a class of tissues that are in the same physiological state, which implies that the intraclass variability due to this factor should be assessed for a specific problem, not considering it random. For this purpose, in our work, we constructed optical phantoms simulating various thicknesses of the subcutaneous adipose tissue in order to determine the effect of its light scattering on the diffuse reflectance spectrum and to select the optimal configuration of optical fibers

Optical Spectral Approach to Breast Tissue Oxygen Saturation Analysis for Mastectomy Perioperative Control

The purpose of our research is to study the ability of the developed method of hemoglobin detection, based on the fiber-optic spectral analysis in visible region, to determine the level of blood supply to breast tissues before surgical treatment, intraoperatively and during observation of the patient in the postoperative period, when breast tissue is healing. The significant effect of subcutaneous adipose tissue on the shape of diffuse reflectance spectra due to scattering leads to a decrease in the accuracy of determining hemoglobin oxygen saturation and hemoglobin concentration from them. The variability of the subcutaneous adipose tissue layer is quite high, which also leads to a high variability of the spectra within a class of tissues that are in the same physiological state, which implies that the intraclass variability due to this factor should be assessed for a specific problem, not considering it random. For this purpose, in our work, we constructed optical phantoms simulating various thicknesses of the subcutaneous adipose tissue in order to determine the effect of its light scattering on the diffuse reflectance spectrum and to select the optimal configuration of optical fibers