Objective: The problem of devising an education quality assessment system at a medical higher educational institution has been analyzed in the article. The authors compare the views on the ...interpretation of the concept of “quality of education”, as well as examine the principles and criteria for the quality of education. A new approach to the internal system for assessing the quality of education at a medical higher education is offered in the article on the basis of the integration of all the components of the pedagogical system. The following components of the internal system of education quality assessment are considered: the conceptual component (forecasting, planning the strategic areas of the educational process development to achieve the quality of education, the mission and objectives), the procedural content component (monitoring at the initial and final stages of the education quality assessment), the self-analysis component (the analysis of students, teachers, department chairs’ activity); the analytical component (visualization of information obtained on the basis of transparency, informational openness of learning and upbringing results, the analysis and elimination of identified shortcomings, the introduction of advanced pedagogical experience into the educational process). Method: The study was conducted at the FSAEI HE I.M. Sechenov First Moscow State Medical University of the Ministry of Healthcare of the Russian Federation (Sechenov University) in the period from February 2011 to March 2017. The sample group size was determined with the use of a special formula. Based on the sample size, 450 respondents were included in the study, and the number of people who would drop out was determined in the sample (n = 429), so the sample was representative in terms of quality and quantity. The students from 1 to 6 years were involved in the study in five training programs of the university who were randomly selected. An original questionnaire was devised. The questionnaire contained some standard questions and special questions on the research topic. Results: The main contingent of students is satisfied with the quality of education at Sechenov University and the level assessment of the quality of education is higher in comparison to other universities, but among the final-year students the assessment of the quality of education compared with other universities does not differ significantly. To attract applicants to FSAEI HE I.M. Sechenov First Moscow State Medical University the significant factors were: preserving a good reputation of the university (64.7%), prestige (53%) and the quality of education (50.7%). The most popular competencies among students of all the faculties and courses were the following: willingness to work with modern medical equipment (45% ± 2,3%), knowledge of innovative medical technologies (31,9% ± 2,2%). Almost every second student (55% ± 2.3%) believes that the quality of education at Sechenov University corresponds to the requirements of the current labor market. Conclusion: The conclusion has been drawn on the basis of the conducted research, that the internal system of assessing the quality of education is directed to increasing prestige of Russian higher medical education, its integration into the international educational space.
The dependence of single channel conductance formed by α-latroinsectotoxin (α-LIT) from black widow spider venom in the planar phospholipid membrane on the hydrodynamic radii of different ...nonelectrolytes allowed to determine the geometry of α-LIT water lumen. It was found that the cis- and trans-entrances of α-LIT channel had the same effective radii of 0.55–0.58 nm. Relatively small conductance of α-LIT channel (23.5
+
3.7 pS) in a symmetrical membrane bathing solution of 100 mM KCl (pH 7.4) may result from the constriction inside the channel with apparent radius of 0.37 nm located 32.5% of channel length away from the cis-entrance.
Pure α-latrotoxin is very inefficient at forming channels/pores in artificial lipid bilayers or in the plasma membrane of non-secretory cells. However, the toxin induces pores efficiently in COS-7 ...cells transfected with the heptahelical receptor latrophilin or the monotopic receptor neurexin. Signaling-deficient (truncated) mutants of latrophilin and latrophilin-neurexin hybrids also facilitate pore induction, which correlates with toxin binding irrespective of receptor structure. This rules out the involvement of signaling in pore formation. With any receptor, the α-latrotoxin pores are permeable to Ca2+ and small molecules including fluorescein isothiocyanate and norepinephrine. Bound α-latrotoxin remains on the cell surface without penetrating completely into the cytosol. Higher temperatures facilitate insertion of the toxin into the plasma membrane, where it co-localizes with latrophilin (under all conditions) and with neurexin (in the presence of Ca2+). Interestingly, on subsequent removal of Ca2+, α-latrotoxin dissociates from neurexin but remains in the membrane and continues to form pores. These receptor-independent pores are inhibited by anti-α-latrotoxin antibodies. Our results indicate that (i) α-latrotoxin is a pore-forming toxin, (ii) receptors that bind α-latrotoxin facilitate its insertion into the membrane, (iii) the receptors are not physically involved in the pore structure, (iv) α-latrotoxin pores may be independent of the receptors, and (v) pore formation does not require α-latrotoxin interaction with other neuronal proteins.
The venom of the black widow spider (BWSV) (Latrodectus mactans tredecimguttatus) contains several potent, high molecular mass (110 kDa) neurotoxins that cause neurotransmitter release in a ...phylum-specific manner. The molecular mechanism of action of these proteins is poorly understood because their structures are largely unknown, and they have not been functionally expressed. This study reports on the primary structure of delta-latroinsectotoxin (delta-LIT), a novel insect-specific toxin from BWSV, that contains 1214 amino acids. delta-LIT comprises four structural domains: a signal peptide followed by an N-terminal domain that exhibits the highest degree of identity with other latrotoxins, a central region composed of 15 ankyrin-like repeats, and a C-terminal domain. The domain organization of delta-LIT is similar to that of other latrotoxins, suggesting that these toxins are a family of related proteins. The predicted molecular mass and apparent mobility of the protein (approximately 130 kDa) encoded in the delta-LIT gene differs from that of native delta-LIT purified from BWSV (approximately 110 kDa), suggesting that the toxin is produced by proteolytic processing of a precursor. MALDI-MS of purified native delta-LIT revealed a molecular ion with m/z+ of 110916 +/- 100, indicating that the native delta-LIT is 991 amino acids in length. When the full-length delta-LIT cDNA was expressed in bacteria the protein product was inactive, but expression of a C-terminally truncated protein containing 991 residues produced a protein that caused massive neurotransmitter release at the locust neuromuscular junction at nanomolar concentrations. Channels formed in locust muscle membrane and artificial lipid bilayers by the native delta-LIT have a high Ca2+ permeability, whereas those formed by truncated, recombinant protein do not
A cDNA encoding a 100-kDa subunit (XenNR1) of the N-methyl-D-aspartate (NMDA) glutamate receptor type has been cloned from Xenopus central nervous system. When XenNR1 is coexpressed in a mammalian ...cell line with a recently cloned 51-kDa non-NMDA receptor subunit (XenU1), also from Xenopus, it forms a functional unitary receptor exhibiting the pharmacological properties characteristic of both NMDA and non-NMDA receptors. Firstly, XenU1 can replace NR2 subunits, in complementing XenNR1 to introduce the ligand binding properties of a complete NMDA receptor. Second, responses to both NMDA and non-NMDA receptor agonists and antagonists were obtained in patch-clamp recordings from the cotransfected cells, but no significant responses were recorded when the cells were singly transfected. Third, from solubilized cell membranes from the cotransfected cells, an antibody to the NR1 subunit coprecipitated the binding sites of the non-NMDA receptor subunit. The unitary glutamate receptor has a unique set of properties that denote intersubunit interaction, including a glycine requirement for the responses to non-NMDA as well as to NMDA receptor agonists and voltage-dependent block by Mg2+ of the non-NMDA agonist responses.
1
The pharmacological properties of the ATP‐activated conductance in isolated sensory neurones of the rat were investigated by use of voltage clamp and concentration clamp techniques.
2
Adenosine ...5′‐triphosphate (ATP), adenosine 5′‐diphosphate (ADP), cytidine 5′‐triphosphate (CTP), cytidine 5′‐diphosphate (CDP) and some derivatives activate these receptors, whereas adenosine 5′‐monophosphate (AMP), cytidine 5′‐monophosphate (CMP) and other naturally‐occurring nucleotides are competitive blockers.
3
In the sequence of substances, adenosine 5′‐(β,γ‐methylene)‐triphosphonate (APPCP), adenosine 5′‐(β,γ‐difluoromethylene)− triphosphonate (APPCF2P), adenosine 5′‐(β,γ‐dichloromethylene)‐triphosphonate (APPCC12P) and adenosine 5′‐(β,γ‐dibromomethylene)triphosphonate (APPCBr2P), the properties of ligands depend on the radius of the atom linked to the carbon of the diphosphonate group. Thus, APPCP is an agonist, APPCF2P is a partial agonist, while dichloromethylene and dibromomethylene analogues of adenosine 5′‐(β,γ‐methylene)triphosphonate demonstrate features of competitive blockers. APPCC12P is the most effective blocker of ATP‐receptors (inhibition constant Ki = 21 ± 4μm). An adenosyl or adenylyl radical, when connected to the terminal phosphate of ATP, converts the agonist into a partial agonist.
4
Two especially important parts of the ATP molecule are crucial for the interactions with receptors. They are: (1) the vicinity of C6 of the purine ring and (2) the polyphosphate chain. Some modifications in these regions of the molecule result in the transformation of an agonist into an antagonist.
The vitamin B
1 (thiamine) structural analogue 3-decyloxycarbonylmethyl-4-methyl-5-(β-hydroxyethyl) thiazole chloride (DMHT) (0.1 mM) reversibly reduced transmembrane currents in CaCl
2 and KCl ...solutions via ionic channels produced by latrotoxins (α-latrotoxin (α-LT) and α-latroinsectotoxin (α-LIT)) from black widow spider venom and sea anemone toxin (RTX) in the bilayer lipid membranes (BLMs). Introduction of DMHT from the cis-side of BLM bathed in 10 mM CaCl
2 inhibited transmembrane current by 31.6
±
3% and by 61.8
±
3% from the trans-side of BLM for α-LT channels. Application of DMHT in the solution of 10 mM CaCl
2 to the cis-side of BLM decreased the current through the α-LIT and RTX channels by 52
±
4% and 50
±
5%, respectively. Addition of Cd
2+ (1 mM) to the cis- or trans-side of the membrane after the DMHT-induced depression of Ca
2+-current across the α-LT channels caused its further decrease by 85
±
5% that coincides favorably with the intensity of Cd
2+ blocking in control experiments without DMHT. These data suggest that DMHT inhibiting is not specific for latrotoxin channels only and DMHT may exert its action on α-LT channels without considerable influence on the ionogenic groups of Ca
2+-selective site inside the channel cavity. The binding kinetics of DMHT with the α-LT channel shows no cooperativity and allows to expect that the DMHT binding site of the toxin is formed by one ionogenic group as the slopes of inhibition rate determined in log–log coordinates are 1.25 on the trans-side and 0.68 on the cis-side. Similar pK of binding (5.4 on the trans-side and 5.7 on the cis-side) also suggest that DMHT may interact with the same high affinity site of α-LT channel on either side of the BLM. The comparative analysis of effective radii measured for α-LT, α-LIT and RTX channels on the cis-side (0.9 nm, 0.53 nm and 0.55 nm, correspondingly) and for α-LT channel on the trans-side (0.28
±
0.18 nm) with the intensity of DMHT inhibitory action obtained on these channels allowed to conclude that the potency of DMHT inhibition increased on toxin pores of smaller lumen.
We examined the effect of argiopine and argiopinine 3, low molecular weight polyamine venom components of the spider Argiope lobata, on rat cortical excitatory amino acid (EAA) receptors expressed in ...Xenopus oocytes. Responses to 100 microM N-methyl-D-aspartate (NMDA) with 10 microM glycine were blocked by both of the polyamine toxins in a dose-dependent manner. Both compounds had similar potencies against 100 microM kainate or 50 microM (S)-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (L-AMPA). Oscillatory responses to 2 microM quisqualate were unaffected by either polyamine toxin. Increasing concentrations of either NMDA, kainate or AMPA were unable to overcome the antagonism by either spider toxin. We were able to demonstrate a use-dependent phenomenon similar to that of phencyclidine; neither polyamine toxin affected the NMDA, kainate or AMPA response without the presence of the respective agonist.
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