VILNIAUS UNIVERSITETAS GAMTOS MOKSLŲ FAKULTETAS BIOCHEMIJOS IR BIOFIZIKOS KATEDRA Olga Sevriukova Acetilcholino poveikio menturdumblių lastelių membranų elektriniams parametrams tyrimas fiksuotos įtampos metodu. Magistrinis darbas Santrauka Informacijos perdavimas augaluose, kaip ir visuose gyvuose organizmuose, yra vienas iš pagrindinių gyvybiškai svarbių procesų. Informacija apie pasikeitusias aplinkos sąlygas, gresiantį pavojų, pažaidas ir daugelį kitų veiksnių gyvose sistemose perduodama įvairių signalų pavidalu. Acetilcholinas – tai vienas iš neurotransmiterių, dalyvaujančių signalų perdavime tarp gyvūninių nervinių ląstelių. Kadangi ši medžiaga taip pat aptinkama ir augaluose, šio darbo tikslas buvo išsiaiškinti, ar acetilcholinas dalyvauja augalinių ląstelių elektrogenezėje. Vienas iš būdų ištirti ląstelės atsaką į kokį nors išorinį dirgiklį, yra registruoti jos elektrinius parametrus prieš ir po siunčiamo signalo ir vertinti jų pokyčius. Fiksuotos įtampos metodu galima tirti įvairiu medžiagų poveikį elektriniams augalinių ląstelių membranų parametrams, tokiems kaip joninių srovių amplitudė, dinamika, sužadinimo slenkstis. Darbo metu šiuo metodu buvo tiriamas acetilcholino poveikis menturdumblio Nitellopsis obtusa internodalinių ląstelių Cl- ir Ca2+ srovių stiprumui, membranos laidumui Cl- jonams, Cl- srovės aktyvacijos ir inaktyvacijos latencijai bei trukmei, sužadinimo slenksčiui ir reversijos potencialui. Pasirinktas tyrimo objektas Nitellopsis obtusa yra labai... [toliau žr. visą tekstą] / VILNIUS UNIVERSITY FACULTY OF NATURAL SCIENCES BIOCHEMISTRY AND BIOPHYSICS DEPARTMENT Olga Sevriukova The investigation of acetylcholine effect on the plant cell membrane electrical parameters applying voltage clamp method Master’s thesis Summary Information transfer in plants, like in all living beings, is one of the main vital processes. Information about the changes of environmental conditions, possible risk, disturbances and many other factors in living systems is transmitted in the form of different signals. Acetylcholine is one of the neurotransmitters, which takes part in transfer of the signals among nerve-cells of animals in the form of action potential. While this material is found also in plants, the aim of this study was to find out, whether it takes part in plants electrogenesis. One of the possible ways to study the cell response to any external stimulus is to register the electrical parameters of cell before and after the signal transmission and evaluate their differences. It is possible to investigate the influence of different materials on plant cell membrane electrical parameters, like ion currents amplitude, dynamics and the current excitation threshold, using voltage-clamp method. This method was used during this study to analyse the influence of acetylcholine on electrical parameters of internodular cells of Nitellopsis obtusa. Such object of investigation as Nitellopsis obtusa is very convenient, because its cells are large enough (up to 10 cm long) and... [to full text]

In this study, we demonstrated that membrane immunofluorescence (MIF) with canine erythrocytes is a much more sensitive diagnostic technique compared with the Coombs test to detect auto-antibodies on RBC. We also demonstrate how the evaluation of the MIF test can be made more precisely which results in a more clear interpretation. Till nowadays the Evans syndrome (combined thrombocytopenia and anemia) is not very well diagnosed in dogs. Only a few studies with low animal numbers tested auto-antibodies on RBC and thrombocytes. Here we describe the frequency of Evans syndrome based on the evaluation of a large data set with 557 dogs. The novelty of the thesis also lies in making a research of the amount of CICs in sera of AIHA/AITP patients is described as well as the cytotoxic potential of patient’s sera for canine leucocytes. These new aspects of diagnosis (AIHA) and pathogenesis (AIHA/AITP) are not only relevant for dogs but also for humans and can be used for better differential diagnosis in medicine. The new findings with respect to circulating immune complexes and cytotoxicity are also offer new therapeutic concepts. Besides, the study has resulted in the characterization of monoclonal antibodies which allow for the detection of so far undetectable canine differentiation antigens (CD molecules) on canine erythrocytes (CD235) and thrombocytes (CD42a). The identified mAbs are useful in the identification of relevant target structures for autoantibodies on these cells.