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Modeling: The New Prospects of Studying Biological Systems as Illustrated by the Human Stomach

Authors:
  • Tananaev Institute of Chemistry - Subdivision of the Federal Research Centre “Kola Science Centre of the Russian Academy of Sciences”

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Thermodynamic modeling was undertaken of the interactions between gastric juice and the mineral water sampled from the Marcial water well and spring in the vicinity of the city of Apatity. The study results make it possible to determine the migration forms of elements in the natural water—gastric juice system in a low and high acidity environment and the deposition conditions of the mineral phases that can be transported from the stomach to other organs and tissues. The physicochemical parameters (Eh and pH) of the studied gastric juice model were examined under normal conditions as well as deficient and excessive HCl. Important factors affecting the change in the gastric juice parameters are temperature and the intake of different mineral water varieties containing different concentrations of the individual elements. It was shown that, in stomach disorders, the transition of iron from the solution to the solid phase occurs, which may explain the anemic condition. A successful treatment of this condition requires restoring the acid-base parameters of the system. The study results complement the existing knowledge and open up new prospects of applying thermodynamic modeling methods to biological systems. An attempt was made to apply the thermodynamic modeling method to study the processes occurring in the human stomach.
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... Рассмотрим возможные формы миграции элементов, полученных в физико-химической модели [25], в результате взаимодействия природных вод (проба 5) с желудочным соком в зависимости от концентрации (С) в желудке соляной кислоты: 1) рН 2.02, Eh = +0.044 В, С(НCl) = 2872.3 ...
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Объективной оценкой состояния окружающей среды являются показатели здоровья человека. В Мурманской области по заболеваниям костно-мышечной системы и мочекаменной болезни выделяются города Кировск и Апатиты, а также Ловозерский район, население которых используют воду, формирующуюся в пределах гигантских щелочных массивов - Хибинского и Ловозерского, содержащих оксиды стронция, тория, бария и редкоземельных металлов. Путем физико-химического моделирования с использованием программного комплекса “Селектор” исследована система “раствор - кристаллическое вещество” с учетом условий окружающей среды и физиологических показателей организма человека. В качестве раствора использованы природные питьевые воды, желудочный сок, смесь питьевых вод и желудочного сока, в качестве кристаллического вещества - новообразованные фазы, равновесные с раствором. Исследованы химические формы миграции элементов, в том числе урана, и определены условия выпадения минеральных фаз в системе “природные воды - желудочный сок” в условиях пониженной и повышенной кислотности. Показано, что формы миграции элементов (Ni2+, Ba2+, Pb2+, Sr2+) остаются канцерогенными или токсичными при температурах и параметрах среды желудка. Предложенный подход открывает новые возможности в экологических и медико-экологических исследованиях. Objective evaluation of the state of the environment may be made on the basis of the parameters of human health. The cities of Kirovsk, Apatity, and the Lovozersky district stand out among the cities and districts of the Murmansk Region for the diseases of the musculoskeletal system and urolithiasis. The population of these areas uses water formed within the giant alkaline massifs - Khibiny and Lovozero, containing the oxides of strontium, thorium, barium and rare earths. The solution – crystalline substance system was studied with the help of physicochemical modeling using the Selector software package. Environmental conditions and physiological parameters of the human organism were taken into account. Natural drinking water, gastric juice, a mixture of drinking waters and gastric juice were considered as the solution, while the newly formed phases in equilibrium with solution were considered as the crystalline substance. The chemical forms of the migration of elements including uranium were studied, and the conditions of mineral phase precipitation in the system natural waters – gastric juice under the conditions of reduced and increased acidity were investigated. It was demonstrated that the forms of element migration (Ni2+, Ba2+, Pb2+, Sr2+) remain carcinogenic or toxic at the temperature and parameters existing in the stomach. The proposed approach opens new outlooks in environmental and medical-ecological studies.
... The consequences of the stability in the digestive tract have impact on the bioavailability of the nutrients in the body [52]. The human stomach secretes up to 2 L of gastric juice per day [53]. The natural sources such as shepherd's purse (Capsella bursa-pastoris), celery (Apium graveolens) and common sage (Salvia plebeia R.Br.) are rich sources of apigetrin containing about 7 mg, 7.5 mg and 144.4 mg per 100 g in dry weight, respectively [54]. ...
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