Jagiellonian University

About: Jagiellonian University is a education organization based out in Krakow, Poland. It is known for research contribution in the topics: Population & Catalysis. The organization has 17438 authors who have published 44092 publications receiving 862633 citations. The organization is also known as: Academia Cracoviensis & Akademia Krakowska.

Regulation of ATP supply during muscle contraction: theoretical studies.

Abstract: The dynamic computer model of oxidative phosphorylation developed previously and successfully tested for large-scale changes in fluxes and metabolite concentrations was used to study the question of how the rate of ATP production by oxidative phosphorylation is adjusted to meet the energy demand during muscle contraction, which causes a great increase in ATP consumption in relation to the resting state. The changes in the respiration rate and ATP/ADP ratio after the onset of maximal work measured experimentally were compared with simulated changes in the respiration rate and ATP/ADP in several different cases, assuming direct activation of different steps by an external effector. On the basis of the computer simulations performed, it was possible to conclude which enzymes/metabolic blocks should be directly activated to cause the experimentally observable changes in fluxes and metabolite concentrations. The theoretical results obtained suggest that the parallel direct activation of actinomyosin-ATP-ase and oxidative phosphorylation by an external effector (for example calcium ions) is the main mechanism responsible for fitting of ATP production to ATP consumption, while the negative feedback via an increase in ADP concentration (decrease in ATP/ADP), which indirectly activates the ATP supply, plays only a minor role. Additionally, the conclusion is drawn that most of the oxidative phosphorylation steps should be directly activated in order to explain the observed changes in the respiration rate and ATP/ADP ratio (and also in other parameters) during muscle contraction. It is suggested that there should exist a universal external activator/regulatory mechanism which causes a parallel stimulation of different enzymes/processes. A possible nature of such an activator is shortly discussed.

Middle triassic evolution of the northern peri-tethys area as influenced by early opening of the tethys ocean

Abstract: Ewolucja środkowotriasowa polnocnej Paratetydy i jej związki z rozwojem Oceanu Tetydy During Middle Triassic times, the Germanic or northern Peri-Tethys Basin pertained to the western Tethys Ocean. The basin was closed from the north and open toward the Tethys by tectonically controlled depressions (gates). The gates were opened in different times. The marine incursions broke first (as early as in late Scythian time) through the eastern gates and from the Polish Basin advanced gradually to the west. Semiclosed disposition of the basin resulted in its distinctive environmental diversification. Open marine environments developed along the southeastern margins which should be regarded as an integrate part of the Tethys Ocean rather than the epicontinental sea. Northward and westward from the Silesian and Carpathian domains the environments became more restricted. This resulted in significant facies diachronity between the western and eastern parts of the basin. As indicated by the faunal diversity, facies variability and geochemical properties of the sediments, during almost entire Anisian time the open marine sedimentation dominated in the eastern part while the western part displayed restricted circulation, typical for the semi-closed, evaporitic basin. The circulation reversed in Ladinian time when the westward shift of the tethyan spreading center gave rise to opening of the western gate. Meanwhile, the eastern and northern parts of the basin were uplifted and underwent emersion by the end of the Ladinian. Evolution of the southern parts of the Germanic Basin (Silesia, Holy Cross Mts., SW Germany) has been directly influenced by the Tethys rifts. The crustal motion was transmitted from the Tethys rift onto its northern periphery by reactivated Hercynian master faults. The Northern Germany and the North Sea basins were controlled by the North Atlantic-Arctic rift system. The central part of the basin was dominated by thermal subsidence. Despite of the intense synsedimentary tectonism affecting the basin, the distinguished 3ld order depositional sequences resulted from eustatic controls. The concordance between the tethyan and peritethyan sequence stratigraphy argues for the overregional, eustatic nature of the sequences. Faunal migration from the Tethys into its northern periphery followed generally the rift-controlled opening of the seaways within the Tethys. The first tethyan faunas which appeared in the south-eastern part of the Polish Basin as early as in Induan time came from the eastern branch of the Tethys Ocean (Paleo-Tethys). The next migration waves proceeded by western branches of the spreading ocean (Neo-Tethys) and entered the Germanic Basin through the Silesian-Moravian Gate (in Anisian time) and through the Western Gate from Ladinian time onward. W czasie środkowego triasu basen germanski nalezal do polnocnego obrzezenia Oceanu Tetydy nazywanego polnocną Perytetydą. Taka pozycja paleogeograficzna wskazuje ze basen germanski nalezy traktowac raczej jako integralną cześc zachodniej Tetydy niz jako typowy basen epikontynentalny. Bezpośrednie polączenie miedzy obszarem germanskim a Tetydą utrzymywane bylo przez system tektonicznie generowanych obnizen (bram) rozwinietych w obrebie speneplenizowanego lądu windelicko-bohemskiego stanowiącego strukturalną bariere miedzy otwartym oceanem i jego strefą peryferyjną. Przez wiekszą cześc środkowego triasu basen germanski wykazywal cechy basenu polzamknietego o ograniczonej i jednokierunkowej cyrkulacji. Taki uklad hydrologiczny powodowal ewaporacyjny wzrost zasolenia wod basenu w miare oddalania sie od strefy doplywu wod oceanicznych. Znajduje to potwierdzenie w wyraźnym ubozeniu zespolow fauny zasiedlającej zbiornik jak i w zapisie izotopow stabilnych wegla i tlenu. Otwieranie bram mialo charakter diachroniczny i postepowalo ze wschodu na zachod. Najwcześniej, bo juz w środkowej cześci wczesnego triasu otwarta byla tzw. Brama Wschodniokarpacka. W anizyku glownym polączeniem byla Brama Morawsko-Sląska a w ladynie Brama Zachodnia. Diachronizm w otwieraniu bram byl pochodną migracji glownej strefy spreadingu tetydzkiego, ktora przemieszczala sie ze wschodu na zachod. Wyroznione dla basenu germanskiego sekwencje depozycyjne trzeciego rzedu wykazują dobrą korelacje z sekwencjami z basenow alpejskich co pozwala stwierdzic, ze cykle transgresywno-regresywne w basenie germanskim kontrolowane byly glownie przez wahania eustatyczne. Subtropikalna pozycja paleogeograficzna polnocnej Perytetydy warunkowala jej gorący i polsuchy klimat. Okresowe zwilgotnienia w poźnym ladynie i w karniku byly pochodną przebudowy tektonicznej i intensywnej dzialalności wulkanicznej w obrebie Tetydy.

An Expert Opinion From the European Society of Hypertension-European Union Geriatric Medicine Society Working Group on the Management of Hypertension in Very Old, Frail Subjects.

Abstract: Two years after the publication of the 2013 guidelines for the management of arterial hypertension of the European Society of Hypertension (ESH) and the European Society of Cardiology (ESC),1 the ESH and the European Union Geriatric Medicine Society have created a common working group to examine the management of hypertensive subjects aged >80 years. The general term hypertension in the elderly is not sufficiently accurate because it mixes younger old patients (60–70 years) with the oldest old. Our group believes that the management of hypertension in individuals aged ≥80 years should be specifically addressed. Although arbitrary, this cutoff value identifies a population that is expanding faster than any other age group with a 50% increase of life expectancy during the past 50 years2,3; furthermore, the incidence and prevalence of comorbidities, frailty, and loss of autonomy greatly increases after the age of 80 years4; finally, although there is limited evidence on the management of hypertension in this age group, the latest clinical studies indicate that in these patients, treatment may not be the same as in patients in the lower age strata. The aim of this Working Group was to discuss more in-depth treatment aspects of hypertensive patients aged ≥80 years or older, with special focus on the difficulties and uncertainties posed by very old frail individuals. We focused, in particular, on the following points of the 2013 ESH/ESC guidelines: The 2013 ESH/ESC guidelines1 reported the results of the Hypertension in the Very Elderly Double Blind Trial (HYVET). This showed that in hypertensive patients aged ≥80 years, the administration of the thiazide-like diuretic indapamide supplemented, if necessary, by the angiotensin-converting enzyme inhibitor perindopril led to a significant reduction in the …