Co-crystalization and in vitro biological characterization of 5-Aryl-4-(5-substituted-2-4-dihydroxyphenyl)-1,2,3-thiadiazole Hsp90 inhibitors

A potential therapeutic strategy for targeting cancer that has gained much interest is the inhibition of the ATP binding and ATPase activity of the molecular chaperone Hsp90. We have determined the structure of the human Hsp90α N-terminal domain in complex with a series of 5-aryl-4-(5-substituted-2-4-dihydroxyphenyl)-1,2,3-thiadiazoles. The structures provide the molecular details for the activity of these inhibitors. One of these inhibitors, ICPD 34, causes a structural change that affects a mobile loop, which adopts a conformation similar to that seen in complexes with ADP, rather than the conformation generally seen with the pyrazole/isoxazole-resorcinol class of inhibitors. Competitive binding to the Hsp90 N-terminal domain was observed in a biochemical assay, and these compounds showed antiproliferative activity and induced apoptosis in the HCT116 human colon cancer cell line. These inhibitors also caused induction of the heat shock response with the upregulation of Hsp72 and Hsp27 protein expression and the depletion of Hsp90 clients, CRAF, ERBB2 and CDK4, thus confirming that antiproliferative activity was through the inhibition of Hsp90. The presence of increased levels of the cleavage product of PARP indicated apoptosis in response to Hsp90 inhibitors. This work provides a framework for the further optimization of thiadiazole inhibitors of Hsp90. Importantly, we demonstrate that the thiadiazole inhibitors display a more limited core set of interactions relative to the clinical trial candidate NVP-AUY922, and consequently may be less susceptible to resistance derived through mutations in Hsp9

Effect of variable rate seeding on winter wheat seedbed and germination parameters using soil apparent electrical conductivity

Due to the variability of soil characteristics in the field and the rising prices of high-quality seeds, farmers are increasingly interested in applying a system of precision variable rate seeding (VRS), which makes it easier to manage risks in crop production and allows to ensure the profitability of the farm. Most modern seed drills are equipped with a hydraulic or electric drive and a terminal in the tractor cabin, allowing farmers to apply VRS. The aim of this study was to determine the most appropriate seeding rate of winter wheat according to the measured apparent soil electrical conductivity (ECa) in the field, to investigate the uniformity of seed placement by layers in the soil and to evaluate the germination dynamics of winter wheat. Precision seeding was performed using a VRS map, generated from soil ECa data obtained by field surface scanning using the ECa device EM-38 MK2. Winter wheat seeding was implemented with a direct seed drill. The research was carried out by measuring the parameters of winter wheat seedbed and germinated plants, including the number and distribution of seeds in soil layers of different depths, germination, tillering. Field research was performed with 3 treatments and 4 repetitions (1 - uniform rate seeding; 2 - VRS; 3 - VRS + variable rate fertilisation (VRF)). The results of the research showed a direct relationship between the soil ECa and the depth of seed placement. Most seeds were inserted at medium depths (15-30 mm), except in the soil management zone, where ECa was highest (28.8 mS center dot m(-1)). In this area, most seeds (50.7%) were inserted shallowly up to 15 mm. The experimental results of seeding studies showed that using the VRS and VRS + VRF methods in all soil zones the germination of winter wheat was similar, while seeding at the uniform rate yielded significant differences between individual soil zones

Thermodynamics of Aryl-Dihydroxyphenyl-Thiadiazole Binding to Human Hsp90

The design of specific inhibitors against the Hsp90 chaperone and other enzyme relies on the detailed and correct understanding of both the thermodynamics of inhibitor binding and the structural features of the protein-inhibitor complex. Here we present a detailed thermodynamic study of binding of aryl-dihydroxyphenyl-thiadiazole inhibitor series to recombinant human Hsp90 alpha isozyme. The inhibitors are highly potent, with the intrinsic Kd approximately equal to 1 nM as determined by isothermal titration calorimetry (ITC) and thermal shift assay (TSA). Dissection of protonation contributions yielded the intrinsic thermodynamic parameters of binding, such as enthalpy, entropy, Gibbs free energy, and the heat capacity. The differences in binding thermodynamic parameters between the series of inhibitors revealed contributions of the functional groups, thus providing insight into molecular reasons for improved or diminished binding efficiency. The inhibitor binding to Hsp90 alpha primarily depended on a large favorable enthalpic contribution combined with the smaller favorable entropic contribution, thus suggesting that their binding was both enthalpically and entropically optimized. The enthalpy-entropy compensation phenomenon was highly evident when comparing the inhibitor binding enthalpies and entropies. This study illustrates how detailed thermodynamic analysis helps to understand energetic reasons for the binding efficiency and develop more potent inhibitors that could be applied for therapeutic use as Hsp90 inhibitors

Thermodynamics of aryl-dihydroxyphenyl-thiadiazole binding to recombinant human HSP90

Chaperone Hsp90, being essential to the main cancerogenesis pathways, is an attractive target for development of anticancer drugs. A series of potential Hsp90 inhibitors, aryl-dihydroxyphenyl-thiadiazoles, has been synthesised at Vilnius University. The goal of this study was to explore the structure-thermodynamics relationship for aryl-dihydroxyphenyl-thiadiazoles to human Hsp90. We employed isothermal titration calorimetry in conjunction with protein denaturation profile analysis techniques in order to dissect the thermodynamic mechanism of the protein–ligand binding event. In this work we provide a detailed thermodynamic characterisation of these inhibitors binding to recombinant human Hsp90, both α and β isoforms. We show for the first time that protonation of hydroxyl residue in resorcinol-based Hsp90 inhibitors is essential for binding. Comparison of thermodynamic and structural data signified the ability of chlorine to form interactions of non-hydrophobic nature. As generally enthalpic contribution to the ligand affinity is more difficult to improve than the entropic contribution, the mostly enthalpy-driven binding of three of our compounds makes them excellent candidates for further lead development

Aril-dihidroksilfenil-tiadiazolų jungimosi su rekombinantiniu žmogaus Hsp90 baltymu termodinamika

Chaperone Hsp90, being essential to the main cancerogenesis pathways, is an attractive target for development of anticancer drugs. A series of potential Hsp90 inhibitors, aryl-dihydroxyphenyl-thiadiazoles, has been synthesised at Vilnius University. The goal of this study was to explore the structure-thermodynamics relationship for aryl-dihydroxyphenyl-thiadiazoles to human Hsp90. We employed isothermal titration calorimetry in conjunction with protein denaturation profile analysis techniques in order to dissect the thermodynamic mechanism of the protein–ligand binding event. In this work we provide a detailed thermodynamic characterisation of these inhibitors binding to recombinant human Hsp90, both α and β isoforms. We show for the first time that protonation of hydroxyl residue in resorcinol-based Hsp90 inhibitors is essential for binding. Comparison of thermodynamic and structural data signified the ability of chlorine to form interactions of non-hydrophobic nature. As generally enthalpic contribution to the ligand affinity is more difficult to improve than the entropic contribution, the mostly enthalpy-driven binding of three of our compounds makes them excellent candidates for further lead development

Testing on noise level prevailing at motor vehicle parking lots and numeral simulation of its dispersion

In Vilnius and in other bigger towns the noise generated by mobile sources accounts for up to 90 % of the total noise level in a town. A high noise level is detected at motor vehicle parking lots. To measure this noise level, testing was carried out at guarded parking lots which were divided into certain types. One lot of each type was chosen for testing. The number of measuring spots was conditioned by the size of a lot. The data obtained during testing reveal that the highest noise level is generated not at a parking lot but on a nearby street. Such conclusions are proved by the results of testing carried out at a parking lot on È. Sugihara street. Although this lot parks over 100 vehicles, the equivalent noise level is 47 dBA. Basing on the testing data, the numeral simulation of the noise dispersion in areas in the vicinity of parking lots has been run with the help of the numeral simulation software IMMI. Triukšmo automobilių stovėjimo aikštelės tyrimai ir jo sklidimo skaitinis modeliavimas Santrauka Vilniuje ir kituose didesniuose miestuose mobiliųjų šaltinių skleidžiamas triukšmas sudaro iki 90 % viso miesto triukšmo lygio. Aukštas triukšmo lygis esti automobilių stovėjimo aikštelėse. Siekiant jį įvertinti atlikti tyrimai. Saugomas automobilių stovėjimo aikšteles suskirsčius pagal pobūdį, pasirinkta po vieną skirtingo tipo aikštelę. Matavimo taškų skaičių lėmė aikštelės dydis. Gauti tyrimų duomenys rodo, kad didžiausias triukšmas sklinda ne iš pačios automobilių stovėjimo aikštelės, o iš šalia esančios gatvės. Tokią išvadą įrodo triukšmo lygio automobilių stovėjimo aikštelėje Č. Sugiharos gatvėje tyrimo rezultatai. Nors šioje aikštelėje saugoma per 100 automobilių, tačiau nustatyta, kad joje ekvivalentusis triukšmo lygis ‐ 47 dBA. Remiantis tyrimų duomenimis, atliktas triukšmo sklidimo į šalia automobilių stovėjimo aikštelių esančią teritoriją skaitinis modeliavimas. Modeliavimui naudojama skaitinio modeliavimo programa IMMI. Reikšminiai žodžiai: transportas, triukšmas, automobilių aikštelės, modeliavimas, skaitinis First Published Online: 14 Oct 201

Comparative analysis of energy and GHG emissions using fixed and variable fertilization rates

Reducing the overuse of mineral fertilizers in crop production is a key factor related to healthier soil, healthier food, and more economical, efficient, and cleaner agricultural production. The aim of this study was to investigate and to compare the effects of fixed and variable rate fertilization with fertilizer consumption, energy consumption, and environmental impact. A 4-year experimental field study using crop rotation of four plants (spring barley, winter oilseed rape, winter wheat, and faba bean) was performed. Fertilization with phosphorus and potassium at a variable rate were performed and applied based on the soil properties analyzed before the start of the research and completion of the fertilization maps. Nitrogen fertilization was performed by additional fertilization using a proximal N-sensor, which gives the accurate nitrogen uptake in plants in real-time. This was followed by a comparative evaluation analysis of variables and conventional fixed-rate fertilization methods to assess fertilizer consumption, energy consumption, environmental impact, and economic efficiency. The results of the study showed that an application of a variable fertilization rate can reduce the total amount of nitrogen, phosphorus, and potassium fertilizers by 24.9%, energy consumption by 3463.1 kg ha1, and emissions of greenhouse gases (GHG) by 341.5 kg CO2eq ha1 compared to fixed fertilization rate. The method of fertilization with a variable application rate reduced the costs of fertilization, and at the same time, the costs of the total plant production by  168.0 ha1, on averageVytauto Didžiojo universitetasŽemės ūkio akademij

Application of art education in the management and reduction of signs of fatigue in women with MS diagnosis

Reikšminiai žodžiai: Išsėtinė sklerozė; Meninis ugdymas; Menu grįstos veiklos; Nuovargio požymių valdymas ir sumažinimas; Nuovargis; Pacientai su išsėtine skleroze; Art based activities; Art education; Atigue; Fatigue; Management and reduction of signs offatigue; Multiple sclerosis; Patients with M

Effects of Soil Electrical Conductivity and Physical Properties on Seeding Depth Maintenance and Winter Wheat Germination, Development and Productivity

Crop seeding depth is an important parameter in agrotechnologies, but how can seeding depth automatically be maintained in on-farm soil conditions with different textures, granulometric compositions, structural contents and penetration resistances? For this reason, an on-farm field experiment was conducted in the Panevėžys district (Lithuania) during 2020–2022. The field was divided into five zones (EZ1–EZ5) according to soil electrical conductivity. In addition, uniform and variable seeding depths were compared. The results of the investigations showed that soil electrical conductivity was highly correlated with sand (r = −0.867; p ≤ 0.010 > 0.001) and silt (r = 0.871; p ≤ 0.010 > 0.001) contents. The seeding method mainly did not have a significant effect on soil physical properties and winter wheat germination, development and productivity. Higher differences were observed among field zones. The winter wheat seeding depth varied from 27.74 to 33.12 mm between the two most different soil electrical conductivity zones. In zones with variable seeding depths, winter wheat seeds sprouted the most abundantly, and germination reached 99% (in EZ3 and EZ4). In EZ1, EZ2 and EZ4, the yields of grain were the highest and were significantly higher than that in the loamy sand of EZ5. The 1000-grain mass was not affected by any of the tested factors. The results suggest the need for further research in fields with a wider range of soil electrical conductivity. This can increase the variation in seeding depth and reveal interactions among the factors in more detail