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Trusov P.V.,Perm State University | Zaitseva N.V.,Federal scientific center for medical and preventive health risk management technologies | Kamaltdinov M.R.,Perm State University
Mathematical Biology and Bioinformatics | Year: 2015

A submodel of the digestive system is developed within the framework of multilevel model predicting the evolution of human functional disorders under environment influence. The article is dedicated to some problems associated with the submodel of food flow in the stomach. Materials in details is devoted to the reconstruction algorithm of 3D form andtroduodenal part of the digestive tract, based on ultrasonography results, and to the algorithm of the mesh node displacement caused by the antral contraction wave propagation and the pyloric sphincter motor activity. 3D form obtained and mesh configuration changing algorithm translated to program code are used for the flow calculation in antroduodenal part of the tract. Flow characteristics of one/two phased medium with opened/closed pyloric sphincter are analyzed considering functional disorders of the stomach motility; results are compared with 2D case. Further development ways of the stomach submodel and the digestive system model are noted: considering functional disorders of the pyloric sphincter, periodicity disorders of the antral contraction wave propagation in the stomach, processes of the digestive juice secretion, absorption of substances into the circulatory system. © 2015. Source


Romanyuk A.V.,Georgia Institute of Technology | Zvezdin V.N.,Federal scientific center for medical and preventive health risk management technologies | Samant P.,Georgia Institute of Technology | Grenader M.I.,Georgia Institute of Technology | And 2 more authors.
Analytical Chemistry | Year: 2014

Clinical medicine and public health would benefit from simplified acquisition of biological samples from patients that can be easily obtained at point of care, in the field, and by patients themselves. Microneedle patches are designed to serve this need by collecting dermal interstitial fluid containing biomarkers without the dangers, pain, or expertise needed to collect blood. This study presents novel methods to collect biomarker analytes from microneedle patches for analysis by integration into conventional analytical laboratory microtubes and microplates. Microneedle patches were made out of cross-linked hydrogel composed of poly(methyl vinyl ether-alt-maleic acid) and poly(ethylene glycol) prepared by micromolding. Microneedle patches were shown to swell with water up to 50-fold in volume, depending on degree of polymer cross-linking, and to collect interstitial fluid from the skin of rats. To collect analytes from microneedle patches, the patches were mounted within the cap of microcentrifuge tubes or formed the top of V-bottom multiwell microplates, and fluid was collected in the bottom of the tubes under gentle centrifugation. In another method, microneedle patches were attached to form the bottom of multiwell microplates, thereby enabling in situ analysis. The simplicity of biological sample acquisition using microneedle patches coupled with the simplicity of analyte collection from microneedles patches integrated into conventional analytical equipment could broaden the reach of future screening, diagnosis, and monitoring of biomarkers in healthcare and environmental/workplace settings. © 2014 American Chemical Society. Source


Trusov P.V.,Perm National Research Polytechnic Institute | Zaitseva N.V.,Federal scientific center for medical and preventive health risk management technologies | Kamaltdinov M.R.,Perm National Research Polytechnic Institute
Computational and Mathematical Methods in Medicine | Year: 2016

A group of authors has developed a multilevel mathematical model that focuses on functional disorders in a human body associated with various chemical, physical, social, and other factors. At this point, the researchers have come up with structure, basic definitions and concepts of a mathematical model at the "macrolevel" that allow describing processes in a human body as a whole. Currently we are working at the "mesolevel" of organs and systems. Due to complexity of the tasks, this paper deals with only one meso-fragment of a digestive system model. It describes some aspects related to modeling multiphase flow in the antroduodenal portion of the gastrointestinal tract. Biochemical reactions, dissolution of food particles, and motor, secretory, and absorbing functions of the tract are taken into consideration. The paper outlines some results concerning influence of secretory function disorders on food dissolution rate and tract contents acidity. The effect which food density has on inflow of food masses from a stomach to a bowel is analyzed. We assume that the future development of the model will include digestive enzymes and related reactions of lipolysis, proteolysis, and carbohydrates breakdown. © 2016 P. V. Trusov et al. Source


Zaytseva N.V.,Federal scientific center for medical and preventive health risk management technologies | Zemlyanova M.A.,Federal scientific center for medical and preventive health risk management technologies | Zvezdin V.N.,Federal scientific center for medical and preventive health risk management technologies | Dovbysh A.A.,Federal scientific center for medical and preventive health risk management technologies | And 4 more authors.
Voprosy Pitaniia | Year: 2014

Nanostructured amorphous silica (SiO2) is one of the priorities of nanomaterials, exposing human to the ever-increasing scale as a component of food additives, drugs and cosmetic products. According to numerous publications SiO2 nanoparticles (NPs) possess deleterious effects on animal and human cells in vitro and also exhibit inhalation toxicity. However, the biological effects in vivo of silica NPs taken orally are studied insufficiently. This article represents the first section of this study which aim is identification of silica preparation as nanomaterial and estimating of acute toxicity after oral administration in the form of aqueous suspension. Studies of size and shape of the particles in aqueous suspension of silica used in the study by electron and atomic force microscopy, spectroaqustic analysis and dynamic laser light scattering showed that the test substance is a nanomaterial. Estimation of acute toxicity of an aqueous suspension of nanostructured silica with a single intragastric gavage to male BALB/C mice allowed to conclude that the test material has LD50by the oral route greater than 10 000 mg/kg and consequently belongs to class IV (low danger agents). Pathological changes in jejunum and colon of mice in the acute experiment (at a dose of 10 000 mg/kg) haven't been identified. Thus SiO 2 NPs possess low toxicity when administered in the gastrointestinal tract. The available data, however, do not exclude possible presence of adverse effects under their long-term administration by oral way. Source


Zaitseva N.V.,Federal scientific center for medical and preventive health risk management technologies | Zemlyanova M.A.,Federal scientific center for medical and preventive health risk management technologies | Zvezdin V.N.,Federal scientific center for medical and preventive health risk management technologies | Akafieva T.I.,Perm State University | Saenko E.V.,RAS Institute of Technical Chemistry
Nanotechnologies in Russia | Year: 2015

Manganese oxides have been synthesized by the interaction of Mn2+ and Mn in the presence of nanoreactors: cetyltrimethylammonium bromide micelles that were not present in the final product composition. The synthesized substance is investigated using scanning electron microscopy, X-ray diffraction analysis, dynamic light scattering, the Brunauer-Emmett-Teller method, and the method of Barrett-Joyner-Halenda. It is determined that the substance under examination is a filamentous nanometer-scale material with a cross-section size up to 100 nm. The acute inhalation toxicity study is performed according to the interstate standard using the method of acute-toxicity class determination (ATC method) (OECD, Test no. 436:2008, IDT). The ATC method allows us to see that synthesized nanosized manganese oxide has an acute toxicity property when inhaled as an aerosol. Upon 4-h exposure to Wistar rats weighing 190 ± 10g, CL50 is 0.12 mg/L. The clinical picture of acute intoxication is characterized by irritation, neurotoxic effects, and respiratory depression. According to CL50 (>0.05–0.5), mg/L criterion, synthesized nanosized manganese oxide belongs to hazard class 2 in accordance with Globally Harmonized System of Classification and Labelling of Chemicals (GHS). © 2015, Pleiades Publishing, Ltd. Source

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