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Role of the Nitric Oxide (NO) in the Regulation of Steroidogenesis in Placenta During Physiological Pregnancy and Preeclampsia (Experimental Study) 一氧化氮(NO)在生理性妊娠及子痫前期胎盘甾体生成调控中的作用(实验研究)
Current Topics in Biophysics Pub Date : 2019-12-01 DOI: 10.2478/ctb-2019-0003
T. Sanikidze, Levan A. Cheishvili, N. Kipiani, E. Shekiladze, N. Kipiani, G. Sharashenidze, E. Chikvaidze
{"title":"Role of the Nitric Oxide (NO) in the Regulation of Steroidogenesis in Placenta During Physiological Pregnancy and Preeclampsia (Experimental Study)","authors":"T. Sanikidze, Levan A. Cheishvili, N. Kipiani, E. Shekiladze, N. Kipiani, G. Sharashenidze, E. Chikvaidze","doi":"10.2478/ctb-2019-0003","DOIUrl":"https://doi.org/10.2478/ctb-2019-0003","url":null,"abstract":"Abstract The aim of the study was to establish the role of nitric oxide (NO) in the regulation of steroidogenesis in the placenta during physiological pregnancy and experimental preeclampsia (PE) in rats. EPR centers of the placenta, free NO and its metabolites were determined by the Electron Paramagnetic Resonance (EPR) method. At the last stage of pregnancy in the EPR spectra of the rats’ placenta with PE alterations of the signals intensity of mitochondrial steroidogenic electron transport proteins were detected: the FeS-centers of adrenodoxin decreased, the ferricytochrome P-450 increased, the free NO content decreased, and the complexes of NO with heme (HbNO) and non-heme iron (FeSNO) were detected. These data indicate the violation of placental steroidogenesis, which is confirmed by a decrease in the level of progesterone in blood. Therefore, the nitrosylation of mitochondrial proteins is an important redox-dependent mechanism of regulation of the intensity of steroidogenesis.","PeriodicalId":333495,"journal":{"name":"Current Topics in Biophysics","volume":"125 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132461028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Note on Appearance of Zigzak Type Self Similarity in Flying Bird Flocks Performing Directional Collective Motions in Mild-Weather Conditions 关于在温和天气条件下鸟群进行定向集体运动时Zigzak型自相似性出现的注释
Current Topics in Biophysics Pub Date : 2018-12-01 DOI: 10.2478/ctb-2018-0001
A. Gadomski, Janusz Cyran
{"title":"Note on Appearance of Zigzak Type Self Similarity in Flying Bird Flocks Performing Directional Collective Motions in Mild-Weather Conditions","authors":"A. Gadomski, Janusz Cyran","doi":"10.2478/ctb-2018-0001","DOIUrl":"https://doi.org/10.2478/ctb-2018-0001","url":null,"abstract":"Abstract It is argued here that very regular and coordinated patterns of bird flocks in motion, in quiescent weather conditions, can be expected to first emerge upon minimal configurational entropy production for the flock(s) vs. air mass couple. This is immediately to accept if certain ultralow friction conditions apply, with the air-bird flock friction coefficient f approaching minimal values. Then, quite geometrically coordinated, apparently self-similar zigzak type patterns show up during the flock’s motion. Otherwise, the coherence of the flying patterns is lost, the flocks become disorganized, characteristic of fairly large configurational-space (individual positions involving) entropy, and their average acceleration supposedly gets on appreciable nonzero values. The oversimplified analysis performed in this study does not assume really far-from-equilibrium (thermo)dynamic conditions to occur.","PeriodicalId":333495,"journal":{"name":"Current Topics in Biophysics","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114328810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Advances in EPR Dosimetry in Terms of Retrospective Determination of Absorbed Dose in Radiation Accidents EPR剂量学在辐射事故吸收剂量回顾性测定中的研究进展
Current Topics in Biophysics Pub Date : 2018-12-01 DOI: 10.2478/ctb-2018-0002
T. Kubiak
{"title":"Advances in EPR Dosimetry in Terms of Retrospective Determination of Absorbed Dose in Radiation Accidents","authors":"T. Kubiak","doi":"10.2478/ctb-2018-0002","DOIUrl":"https://doi.org/10.2478/ctb-2018-0002","url":null,"abstract":"Abstract The electron paramagnetic resonance measurements of dosimetric signals originating from radicals generated under the influence of ionizing radiation allow to determine the dose absorbed by the casualties of radiation accidents. The study material can consist of victim’s teeth, bones or nails. Also human hair and mineral glass from personal electronic devices, that people had in the moment of accident, are considered to be useful in dosimetry. Although X-band (9.4 GHz) spectrometers predominate, Q-band devices (34 GHz) enable to increase the sensitivity of measurements and reduce the size of specimens, whereas L-band machines (1.1 GHz) are suitable for in vivo dosimetry. The EPR tooth enamel dosimetry has been used many times to assess the cumulative radiation dose and health risk in people living in areas contaminated due to the radiation accidents and to determine the unknown absorbed doses in patients after the overexposures during radiotherapy treatment.","PeriodicalId":333495,"journal":{"name":"Current Topics in Biophysics","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127094499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 7
Comparison of the Overall Motion Correlation Times of Several Mammalian Serum Albumins in Dilute Solutions Determined on the Basis of Maxwell Effect and the Debye-Stokes-Einstein Equation. 基于麦克斯韦效应和德拜-斯托克斯-爱因斯坦方程的几种哺乳动物血清白蛋白在稀溶液中整体运动相关时间的比较
Current Topics in Biophysics Pub Date : 2017-12-01 DOI: 10.1515/ctb-2017-0001
K. Monkos
{"title":"Comparison of the Overall Motion Correlation Times of Several Mammalian Serum Albumins in Dilute Solutions Determined on the Basis of Maxwell Effect and the Debye-Stokes-Einstein Equation.","authors":"K. Monkos","doi":"10.1515/ctb-2017-0001","DOIUrl":"https://doi.org/10.1515/ctb-2017-0001","url":null,"abstract":"Abstract One of the rarely used ways of determining the overall motion correlation time of proteins is method based on the Maxwell effect. This effect consists in the appearance of a stimulated birefringence in liquids or solutions and induced by the mechanical force like shear stress in a streamline flow. To determine the overall motion correlation time for protein in dilute solution is sufficient to know the molecular mass and the ratio of the principal axes of protein, and an intrinsic viscosity. The intrinsic viscosity has been measured using an Ubbelohde-type capillary microviscometer immersed in a water-bath controlled thermostatically in the range from 5°C to 45°C for six mammalian albumins. To check the influence of solution pH on the overall motion correlation time the intrinsic viscosity value of the human serum albumin in solutions at the isoelectric point and beyond of it was measured. The thus obtained correlation times were compared with the times determined on the basis of the Debye-Stokes-Einstein equation.","PeriodicalId":333495,"journal":{"name":"Current Topics in Biophysics","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122050754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Sodium chloride-induced conformational change in tRNA as measured by circular dichroism 通过圆二色性测量，氯化钠诱导tRNA的构象变化
Current Topics in Biophysics Pub Date : 2015-12-01 DOI: 10.1515/ctb-2015-0001
Szymon Sarbak, Melania Kujawa, Hanna Jurga-Nowak, A. Dobek
{"title":"Sodium chloride-induced conformational change in tRNA as measured by circular dichroism","authors":"Szymon Sarbak, Melania Kujawa, Hanna Jurga-Nowak, A. Dobek","doi":"10.1515/ctb-2015-0001","DOIUrl":"https://doi.org/10.1515/ctb-2015-0001","url":null,"abstract":"Abstract The effect of 0.01-1 M sodium ions on the conformation of the folded brewer’s yeast tRNAPhe was examined by circular dichroism method in the region 200-350 nm. The minimum peak at about 210 nm for tRNA solution with 50 mM sodium chloride showed a decrease in magnitude by 26-30% in comparison to that recorded for the solution of higher NaCl content. The depths of the peaks at 225 nm and 233 nm for two solutions with the lowest sodium chloride concentrations (cNaCl = 10mM, cNaCl = 50mM) were changed by 3-10% relative to the those in the spectra of other samples, for the 260 nm maximum peak a decrease in height was 21-25%. In the region 300-350 nm no significant difference was observed. The results point to a strong relationship between concentration of sodium ions and stabilization process of secondary and tertiary tRNA structure, which indicates the influence of sodium ions on stacking and base-pairing interactions.","PeriodicalId":333495,"journal":{"name":"Current Topics in Biophysics","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129622630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Nanoparticle Tracking Analysis of Latex Standardized Beads 乳胶标准化微珠的纳米颗粒跟踪分析
Current Topics in Biophysics Pub Date : 2015-01-01 DOI: 10.2478/CTB-2014-0074
T. Śliwa, M. Jarzębski, K. Szutkowski
{"title":"Nanoparticle Tracking Analysis of Latex Standardized Beads","authors":"T. Śliwa, M. Jarzębski, K. Szutkowski","doi":"10.2478/CTB-2014-0074","DOIUrl":"https://doi.org/10.2478/CTB-2014-0074","url":null,"abstract":"Abstract The most popular technique for particle size characterization is the dynamic light scattering (DLS). In recent years new advanced method based on counting each single particle movement was introduced giving perspective for measurement of each component of mixture. This study presents some advantages of nanoparticle tracking analysis (NTA) method in comparison to DLS. For tests standard polystyrene beds were chosen vary diameter of 22, 61 and 150 nm and its mixtures. Experiments showed that the particles size resolution allows to distinguish each population in two population suspension opposed to DLS. The NTA method permits to eliminate the negative effects i.e. dust or aggregates in sample during post processing, that permits to use it in a variety of studies.","PeriodicalId":333495,"journal":{"name":"Current Topics in Biophysics","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128683062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 4
Pulse Wave Shape Analysis of the Cardiovascular System Using High Signal Resolution 基于高信号分辨率的心血管系统脉冲波形分析
Current Topics in Biophysics Pub Date : 2015-01-01 DOI: 10.2478/CTB-2014-0075
A. Szymił, R. Krzyminiewski, B. Dobosz, A. Pajak, A. Szyszka, M. Ładzińska
{"title":"Pulse Wave Shape Analysis of the Cardiovascular System Using High Signal Resolution","authors":"A. Szymił, R. Krzyminiewski, B. Dobosz, A. Pajak, A. Szyszka, M. Ładzińska","doi":"10.2478/CTB-2014-0075","DOIUrl":"https://doi.org/10.2478/CTB-2014-0075","url":null,"abstract":"Abstract The aim of this study was to carry out the FMD (flow - mediated dilatation) and NID (nitroglycerin-induced dilatation) tests in the case of patients with hypertension by using new measurement method - High Signal Resolution Pulse Wave (HSR PW). The paper presents new diagnostic method HSR PW which was used to evaluate the pulse wave in patients with arterial hypertension. HSR-PW is a method based on increasing the resolution of the pulse wave signal, recorded during a standard test using the Fourier Transform. The study involved twenty-four patients with hypertension and fifteen healthy people as a control group. The analysis showed that changes of the shape of the pulse wave in HSR PW took place in both groups conducting the FMD and NID tests. The HSR PW method proved to be more sensitive to changes in the body then the standard pulse oximeter and therefore may increase clinical practicability.","PeriodicalId":333495,"journal":{"name":"Current Topics in Biophysics","volume":"433 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121172840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Testing Sorption Properties of Halloysite by Means of the Laser Interferometry Method 激光干涉法测试高岭土的吸收特性
Current Topics in Biophysics Pub Date : 2015-01-01 DOI: 10.2478/CTB-2014-0073
S. Wąsik, M. Arabski, Karolina Maciejec, G. Suchanek, A. Świercz
{"title":"Testing Sorption Properties of Halloysite by Means of the Laser Interferometry Method","authors":"S. Wąsik, M. Arabski, Karolina Maciejec, G. Suchanek, A. Świercz","doi":"10.2478/CTB-2014-0073","DOIUrl":"https://doi.org/10.2478/CTB-2014-0073","url":null,"abstract":"Abstract The objective of the present study has been to test the laser interferometry method in terms of its usability for investigating sorption properties of minerals. This method was used to test the absorption capacity of halloysite with reference to glucose, which is often found in industrial wastewater and whose excess can disturb the environmental eco-balance. The sorption capacity of halloysite was thus determined indirectly, basing on the comparison of concentration profiles as well as time characteristics of glucose quantities released from the control solution and from the solution incubated with a halloysite adsorbent. An analysis of glucose diffusion was conducted in a two-chamber membrane system. On the basis of the obtained concentration profiles, the evolution of the concentration field was determined; so were the removal efficiency (%) and the amount of glucose adsorbed at equilibrium (qe, mg/g). The obtained results confirm good sorption properties of halloysite with respect to the investigated substance as well as usability of the method for this kind of investigations. The presented tests suggest that the measurement set-up can be optimised in such as way that visual rendering and testing the kinetics of the adsorbed substance direct release from the studied material become possible.","PeriodicalId":333495,"journal":{"name":"Current Topics in Biophysics","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114170004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
On the Possibility of Indirect Determination of the Glass Transition Temperature of Proteins from Viscosity Measurements and Avramov's Model 粘度测量和Avramov模型间接测定蛋白质玻璃化转变温度的可能性
Current Topics in Biophysics Pub Date : 2015-01-01 DOI: 10.2478/CTB-2014-0076
K. Monkos
{"title":"On the Possibility of Indirect Determination of the Glass Transition Temperature of Proteins from Viscosity Measurements and Avramov's Model","authors":"K. Monkos","doi":"10.2478/CTB-2014-0076","DOIUrl":"https://doi.org/10.2478/CTB-2014-0076","url":null,"abstract":"Abstract The paper presents the results of viscosity determinations on aqueous solutions of hen egg-white lysozyme, bovine ß-lactoglobulin, human and porcine immunoglobulin IgG at a wide range of concentrations and at temperatures ranging from 5oC to 55oC. Viscosity-temperature dependence of the proteins solutions is analyzed based on a formula resulting from the Avramov's model. One of the parameters in the Avramov's equation is the glass transition temperature Tg. It turns out that for all studied proteins, the Tg of the solution increases with increasing concentration. To determine the glass transition temperature of the dry protein Tg,p, a modified form of the Gordon-Taylor equation is used. This equation gives the relationship between Tg and the concentration of the solution, and Tg,p and a parameter dependent on the strength of protein-solvent interaction are fitting parameters. Thus determined the glass transition temperature for the studied dry proteins is in the range from 227.3 K (for bovine ß-lactoglobulin) to 260.6 K (for hen egg-white lysozyme).","PeriodicalId":333495,"journal":{"name":"Current Topics in Biophysics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127004150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Fabrication of Size-Tunable Silica Particles During Seed-Growth Process 在种子生长过程中制备尺寸可调的二氧化硅颗粒
Current Topics in Biophysics Pub Date : 2015-01-01 DOI: 10.2478/CTB-2014-0072
M. Jarzębski, T. Śliwa, Małgorzata Jarzębska, K. Szutkowski
{"title":"Fabrication of Size-Tunable Silica Particles During Seed-Growth Process","authors":"M. Jarzębski, T. Śliwa, Małgorzata Jarzębska, K. Szutkowski","doi":"10.2478/CTB-2014-0072","DOIUrl":"https://doi.org/10.2478/CTB-2014-0072","url":null,"abstract":"Abstract The size control is one of the most important factors during seed-growth process. Although precise determination of ingredients concentrations is easily controllable during the growth process, there is still a possibility to synthesize oversized particles. Nanosized fluorescent silica particles were synthetized using Stöber process and verified using three complementary methods of particle size determination, namely Dynamic Light Scattering (DLS), Particle Tracking (PT) as well as by Transmission Electron Microscopy (TEM) and Confocal Microscopy. The final diameter was verified by DLS and estimated to 494 nm. Parameters necessary to control the size were derived.","PeriodicalId":333495,"journal":{"name":"Current Topics in Biophysics","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125163321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
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