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Hana Stepankova,1,2 Marcin Swiatkowski,3 Rafal Kruszynski,3 Pavel Svec,1 Hana Michalkova,1 Vendula Smolikova,1,2 Andrea Ridoskova,1,4 Zbynek Splichal,1,2 Petr Michalek,1,2 Lukas Richtera,1,2 Pavel Kopel,5 Vojtech Adam,1,2 Zbynek Heger,1,2 Simona Rex1,2 1Department of Chemistry and Biochemistry, Mendel University in Brno, Brno, Czechia; 2Central European Institute of Technology, Brno University of Technology, Brno, Czechia; 3Institute of General and Ecological Chemistry, Lodz University of Technology, Lodz, Poland; 4Central European Institute of Technology, Mendel University in Brno, Brno, Czechia; 5Department of Inorganic Chemistry, Faculty of Science, Palacky University, Olomouc, CzechiaCorrespondence: Simona RexDepartment of Chemistry and Biochemistry, Mendel University in Brno, Brno, CzechiaTel +420-5-4513-3350Fax +425-5-4521-2044Email simona.rex@mendelu.czPurpose: The present study deals with the in vitro evaluation of the potential use of coordination compound-based zinc oxide (ZnO) nanoparticles (NPs) for the treatment of triple negative breast cancer cells (TNBrCa). As BrCa is one of the most prevalent cancer types and TNBrCa treatment is difficult due to poor prognosis and a high metastasis rate, finding a more reliable treatment option should be of the utmost interest.Methods: Prepared by reacting zinc carboxylates (formate, acetate, propionate, butyrate, isobutyrate, valerate) and hexamethylenetetramine, 4 distinct coordination compounds were further subjected to two modes of conversion into ZnO NPs – ultrasonication with oleic acid or heating of pure precursors in an air atmosphere. After detailed characterization, the resulting ZnO NPs were subjected to in vitro testing of cytotoxicity toward TNBrCa and normal breast epithelial cells. Further, their biocompatibility was evaluated.Results: The resulting ZnO NPs provide distinct morphological features, size, biocompatibility, and selective cytotoxicity toward TNBrCa cells. They internalize into two types of TNBrCa cells and imbalance their redox homeostasis, influencing their metabolism, morphology, and ultimately leading to their death via apoptosis or necrosis.Conclusion: The crucial properties of ZnO NPs seem to be their morphology, size, and zinc content. The ZnO NPs with the most preferential values of all three properties show great promise for a future potential use in the therapy of TNBrCa.Keywords: carboxylate, hexamethylenetetramine, nanoparticles, redox homeostasis imbalance, triple negative breast cancer, zinc oxide coordination compounds

Scanning probe microscopy (SPM) since its invention in the 80’s became very popular in examination of many different sample parameters, both in university and industry. This was the effect of bringing this technology closer to the operator. Although the ease of use opened a possibility for measurements without high labour requirement, a quantitative analysis is still a limitation in Scanning ProbeMicroscopes available on the market. Based on experience of Nano-metrology Group, SPM still can be considered as a tool for quantitative examination of thermal, electrical and mechanical surface parameters. In this work we present an ARMScope platform as a versatile SPM controller that is proved to be useful in a variety of applications: fromatomic-resolution STM (Scanning TunnellingMicroscopy) toMulti-resonance KPFM (Kelvin Probe force microscopy) to commercial SEMs (Scanning electron microscopes).

This paper describes the method of homogenization of material properties applied to windings used in power transformers. Exemplary results of natural modes of vibrations obtained by means of finite elements method are also included.

In this work the construction of experimental setup for MEMS/NEMS deflection measurements is presented. The system is based on intensity fibre optic detector for linear displacement sensing. Furthermore the electronic devices: current source for driving the light source and photodetector with wide-band preamplifier are presented.

Two compounds, benzyl-2-(amino(pyrazin-2-yl)methylene)-1-methylhydrazine-1-carbodithioate (L) and its copper(ii) complex Cu(L) were synthesized and studied in terms of their physicochemical properties, including single crystal, spectroscopic and magnetic properties; in silico simulations, including DFT calculations and pharmacokinetic profile analysis; and in vitro biological activity. The Cu(L) compound was found to exhibit good anticancer activity against A375, PANC-1, MKN-74, T-47D, HeLa, and NCI-H1563 cells, with the IC 50 value against the HeLa cell line reaching 17.50 μM, significantly surpassing the activity of the organic ligand. Moreover, at the same time, the Cu(L) complex did not exhibit significant toxicity towards healthy cells. Mechanism of action studies revealed that its activity is connected with the oxidative stress and redox imbalance caused by the upregulation of genes encoding superoxide dismutase (SOD2) and catalase (CAT) antioxidant enzymes. The reported results further underscore the anticancer potential of pyrazine-based copper(ii) complexes., Competing Interests: The Authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

In this study, eighteen new ligands (B1-B18) containing a thiosemicarbazide core were synthesized and characterized in terms of physicochemical properties, molecular docking and in vitro biological activity. The structures of eleven ligands were investigated using X-Ray diffraction and Hirschfeld Surface analysis. To study the structure-activity relationship, the organic ligands contained pyridin-2-ylmethyl, pyridin-3-ylmethyl or pyridin-4-ylmethyl moieties and various substituents. Their pharmakokinetic profiles and molecular docking results suggest high potential as new drug candidates. The complexing ability of the selected organic ligands was also evaluated, yielding five new Cu(II) complexes (Cu(B1)Cl 2 , Cu(B4)Cl 2 , Cu(B10)Cl 2 , Cu(B17)Cl 2 , Cu(B18)Cl 2 ). The obtained results suggest the formation of the polymeric structures. All organic ligands and Cu(II) complexes were tested for anticancer activity against prostate and melanoma cancer cells (PC-3, DU-145, LNCaP, A375, G-361, SK-MEL-28) and normal fibroblasts (BJ), as well as antimicrobial activity against six selected bateria strains. Among B1-B18 compounds, B3, B5, B9, B10, B12 and B14 exhibited cytotoxic activity. The studied Cu(II) complexes were in general more active, with Cu(B1)Cl 2 exhibiting antincancer activity agains all three prostate cancer cells and Cu(B10)Cl 2 reaching the IC 50 value equal to 88 μM against G-361 melanoma cells. Several compounds also exhibited antimicrobial activity against gram-positive and gram-negative bacteria. It was found that the type of specific substituents, especially the presence of -chloro and -dichloro substituents had a greated impact on the cytotoxicity than the position of the nitrogen atom in the pyridylacetyl moiety., (Copyright © 2024. Published by Elsevier Inc.)

Antimicrobial resistance (AMR) is a major public health threat, reducing treatment options for infected patients. AMR is promoted by a lack of access to rapid antibiotic susceptibility tests (ASTs). Accelerated ASTs can identify effective antibiotics for treatment in a timely and informed manner. We describe a rapid growth-independent phenotypic AST that uses a nanomotion technology platform to measure bacterial vibrations. Machine learning techniques are applied to analyze a large dataset encompassing 2762 individual nanomotion recordings from 1180 spiked positive blood culture samples covering 364 Escherichia coli and Klebsiella pneumoniae isolates exposed to cephalosporins and fluoroquinolones. The training performances of the different classification models achieve between 90.5 and 100% accuracy. Independent testing of the AST on 223 strains, including in clinical setting, correctly predict susceptibility and resistance with accuracies between 89.5% and 98.9%. The study shows the potential of this nanomotion platform for future bacterial phenotype delineation., (© 2024. The Author(s).)

Nanomotion technology is a growth-independent approach that can be used to detect and record the vibrations of bacteria attached to cantilevers. We have developed a nanomotion-based antibiotic susceptibility test (AST) protocol for Mycobacterium tuberculosis (MTB). The protocol was used to predict strain phenotype towards isoniazid (INH) and rifampicin (RIF) using a leave-one-out cross-validation (LOOCV) and machine learning techniques. This MTB-nanomotion protocol takes 21 h, including cell suspension preparation, optimized bacterial attachment to functionalized cantilever, and nanomotion recording before and after antibiotic exposure. We applied this protocol to MTB isolates (n = 40) and were able to discriminate between susceptible and resistant strains for INH and RIF with a maximum sensitivity of 97.4% and 100%, respectively, and a maximum specificity of 100% for both antibiotics when considering each nanomotion recording to be a distinct experiment. Grouping recordings as triplicates based on source isolate improved sensitivity and specificity to 100% for both antibiotics. Nanomotion technology can potentially reduce time-to-result significantly compared to the days and weeks currently needed for current phenotypic ASTs for MTB. It can further be extended to other anti-TB drugs to help guide more effective TB treatment., (Copyright © 2023. Published by Elsevier Masson SAS.)

As a result of the synthesis, three new solids, cobalt (II) coordination compounds with benzimidazole derivatives, and chlorides were obtained. The ligands that were used in the synthesis were specially synthesized and were commercially unavailable. During the synthesis, a single crystal of the complex with the L1 ligand was obtained and the crystal structure was refined. All coordination compounds were characterized by elemental analysis, infrared spectroscopy, and thermogravimetric analysis. All the obtained data allowed one to determine the formulas of the new compounds, as well as to determine the method of metal-ligand coordination. Thermal analysis allowed to know the temperature stability of the compounds, solids intermediate and final products of pyrolysis. Additionally, volatile decomposition and fragmentation products have been identified. The toxicity of the compounds and their bioavailability were determined using in silico methods. By predicting activity on cell lines, the potential use of compounds as chemotherapeutic agents has been specified. The blood-brain barrier crossing and the gastrointestinal absorption were defined. Pharmaceutical biodistribution was also simulated.

Investigating novel, biologically-active coordination compounds that may be useful in the design of breast anticancer, antifungal, and antimicrobial agents is still the main challenge for chemists. In order to get closer to solving this problem, three new copper coordination compounds containing thiazole-based derivatives were synthesized. The structures of the synthesized compounds and their physicochemical characterization were evaluated based on elemental analysis, 1 H and l3 C nuclear magnetic resonance (NMR), flame atomic absorption spectroscopy (F-AAS), single-crystal X-ray diffraction, thermogravimetric analysis (TGA), and Fourier-transform infrared spectroscopy (FTIR). The pharmacokinetics were studied using SwissADME. The results obtained from the computational studies supported the results obtained from the MTT analysis, and the antimicrobial activity was expressed as the minimum inhibitory concentration (MIC).

Four complexes of Cd(II) with benzimidazole derivatives were synthesized and named C1, C2, C3, and C4. All coordination compounds were characterized through elemental analysis (EA), flame atomic absorption spectrometry (FAAS), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis coupled with mass spectrometry) (TG-MS), a cytotoxicity assay (MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide)), and computational chemical analysis for absorption, distribution, metabolism, and excretion (ADME). All of the obtained results are compatible and are consistent with the respective structures of the obtained compounds and their properties. The various techniques used allowed the determination of the composition, proposed structure of the compounds, their thermal stability and thermal properties, and the method of coordination between the metal (II) ion and the ligand. The ADME technique was also used to estimate the physicochemical and biological properties. The antitumor activity of the compounds was determined with an MTT assay on the glioblastoma (T98G), neuroblastoma (SK-N-AS), and lung adenocarcinoma (A549) cell lines, as well as normal human skin fibroblasts (CCD-1059Sk). Compound C2 was found to have potential antitumor properties and to be effective in inhibiting the growth of neuroblastoma cells. The antimicrobial activity of Cd complexes, free ligands, and reference drugs was tested against six strains of Gram-positive bacteria, five strains of Gram-negative rods, and three strains of yeasts. Compound C3 significantly increased activity against Gram-positive bacteria in comparison to the ligand.

Developing new, smart drugs with the anticancer activity is crucial, especially for cancers, which cause the highest mortality in humans. In this paper we describe a series of coordination compounds with the element of health, zinc, and bioactive ligands, benzimidazole derivatives. By way of synthesis we have obtained four compounds named C1 , C2 , C4 and C4. Analytical analyses (elemental analysis (EA), flame atomic absorption spectrometry (FAAS)), spectroscopic (Fourier transform infrared spectroscopy (FT-IR), mass spectrometry (MS)) and thermogravimetric (TG) methods and the definition of crystal structures were used to explore the nature of bonding and to elucidate the chemical structures. The collected analytical data allowed the determination of the stoichiometry in coordination compounds, thermal stability, crystal structure and way of bonding. The cytotoxicity effect of the new compounds as a potential antitumor agent on the glioblastoma (T98G), neuroblastoma (SK-N-AS) and lung adenocarcinoma (A549) cell lines and human normal skin fibroblasts (CCD-1059Sk) was also determined. Cell viability was determined by the MTT assay. The results obtained confirmed that conversion of ligands into the respective metal complexes significantly improved their anticancer properties. The complexes were screened for antibacterial and antifungal activities. The ADME technique was used to determine the physicochemical and biological properties.

New derivatives obtained by the combination of unique 1,2,4,5-tetrazine and 4 H -1,2,4-triazole rings have great application potential in many fields. Therefore, two synthetic few-step methodologies, which make use of commercially available 4-cyanobenzoic acid (method A) and ethyl diazoacetate (method B), were applied to produce two groups of the aforementioned heterocyclic conjugates. In both cases, the target compounds were obtained in various combinations, by introducing electron-donating or electron-withdrawing substituents into the terminal rings, together with aromatic or aliphatic substituents on the triazole nitrogen atom. Synthesis of such designed systems made it possible to analyze the influence of individual elements of the structure on the reaction course, as well as the absorption and emission properties. The structure of all products was confirmed by conventional spectroscopic methods, and their luminescent properties were also determined.

A series of new symmetrical s -tetrazine derivatives, coupled via a 1,4-phenylene linkage with a 4 H -1,2,4-triazole ring, were obtained. The combination of these two rings in an extensively coupled system has significant potential applications, mainly in optoelectronics. The methodology used turned out to be useful regardless of the type of five-membered ring or the nature of the individual substituents. All the products were identified by spectroscopic methods, and the target compounds were tested for luminescent properties. This study showed that all the synthesized highly-conjugated triazoles exhibited luminescence; in particular, one derivative, 3,6-bis(4-(5-(4-methoxyphenyl)-4-phenyl-4 H -1,2,4-triazol-3-yl)phenyl)-1,2,4,5-tetrazine ( 13b ), showed strong fluorescence emission and ahigh quantum yield close to 1.

In this paper, we present the first experimental evidence of the piezoelectric nature of struvite (MgNH 4 PO 4 ·6H 2 O). Using a single diffusion gel growth technique, we have grown struvite crystals in the form of plane parallel plates. For struvite crystals of this shape, we measured the piezoelectric coefficients d 33 and d 32 . We have found that at room temperature the value of piezoelectric coefficient d 33 is 3.5 pm/V, while that of d 32 is 4.7 pm/V. These values are comparable with the values for other minerals. Struvite shows stable piezoelectric properties up to the temperature slightly above 350 K, for the heating rate of 0.4 K/min. For this heating rate, and above this temperature, the thermal decomposition of struvite begins, which, consequently, leads to its transformation into dittmarite with the same non-centrosymmetric symmetry as in case of struvite. The struvite-dittmarite transformation temperature is dependent on the heating rate. The higher the heating rate, the higher the temperature of this transformation. We have also shown that dittmarite, like struvite exhibits piezoelectric properties., (© 2021. The Author(s).)

Three new copper coordination compounds derived from 2,2-bis(hydroxymethyl)propionic acid (dmpa) and hexamethylenetetramine (hmta) were obtained and their crystal structures were determined. The stoichiometry of the reagents applied in the syntheses reflects the metal to ligand molar ratio in the formed solid products. Due to the multiple coordination modes of the used ligands, wide structural diversity was achieved among synthesized compounds, i.e., mononuclear [Cu(dmp) 2 (hmta) 2 (H 2 O)] (1), dinuclear [Cu 2 (dmp) 4 (hmta) 2 ] (2), and 1D coordination polymer [Cu 2 (dmp) 4 (hmta)] n (3). Their supramolecular structures are governed by O-H•••O and O-H•••N hydrogen bonds. The compounds were characterized in terms of absorption (UV-Vis and IR) and thermal properties. The relationships between structural features and properties were discussed in detail. Owing to discrepancies in the coordination mode of a dmp ligand, bidentate chelating in 1, and bidentate bridging in 2 and 3, there is a noticeable change in the position of the bands corresponding to the stretching vibrations of the carboxylate group in the IR spectra. The differences in the structures of the compounds are also reflected in the nature and position of the UV-Vis absorption maxima, which are located at lower wavelengths for 1.

Four new ligands and four new copper (II) coordination compounds were prepared and characterized by chemical, elemental analysis, cytotoxicity, and FTIR spectroscopy (Fourier transform infrared spectroscopy). The nature of metal-ligand coordination was investigated. The thermal properties of complexes in the solid state were studied using TG-MS techniques (thermogravimetric analysis coupled with mass spectrometry) under dynamic flowing air atmosphere to analyze the principal volatile thermal decomposition and fragmentation products that evolved during thermolysis. The intermediate and final solid thermolysis products were also determined. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide) assay was used to evaluate active metabolic cells as an IC 50 (half maximal inhibitory concentration). The relationship between antitumor activity and the position of nitrogen atoms in the organic ligand has been shown.

The first coordination compound of copper and tiglic acid named tetrakis(μ-tiglato)bis(tiglic acid)dicopper(II) was synthesized and crystallized from water solution. Its structure was determined and analyzed based on X-ray diffraction measurement. The paddle-wheel coordination system of the investigated compound was compared with other similar copper structures known in the literature. The Hirshfeld analysis was used for the detailed analysis of intermolecular interaction. The new compound was also characterized in terms of infrared absorption, thermal, and magnetic properties. The antiferromagnetic coupling of copper ions was found.

This paper examines the influence of the morphology of zinc oxide nanoparticles (n-ZnO) on the activation energy, vulcanization parameters, crosslink density, crosslink structure, and mechanical properties in the extension of the sulfur vulcanizates of styrene-butadiene rubber (SBR). Scanning electron microscopy was used to determine the particle size distribution and morphology, whereas the specific surface area (SSA) and squalene wettability of the n-ZnO nanoparticles were adequately evaluated using the Brunauer-Emmet-Teller (BET) equation and tensiometry. The n-ZnO were then added to the SBR in conventional (CV) or efficient (EV) vulcanization systems. The vulcametric curves were plotted, from which the cure rate index (CRI) rate of the vulcanization and the activation energy were calculated. The influence on the mechanical properties of the SBR vulcanizates was stronger in the case of the EV curing system than when the CV curing system was used. Of the vulcanizates produced in the EV curing system, the best performance was detected for n-ZnO particles with a hybrid morphology (flat-ended rod-like particles on a "cauliflower" base) and high SSA. Vulcanizates produced using the CV curing system showed slightly better mechanical properties after the addition of nanoparticles with a "cauliflower" morphology than when the rod-like type were used, irrespective of their SSA. In general, nanoparticles with a rod-like structure reduced the activation energy and increased the speed of vulcanization, whereas the cauliflower type slowed the rate of the process and the vulcanizates required a higher activation energy, especially when using the EV system. The crosslink structures were also more clearly modified, as manifested by a reduction in the polysulfidic crosslink content, especially when n-ZnO activators with a rod-like morphology were applied.

A new linear polymeric polyiodide, catena-poly[tris(1,10-phenanthrolin-1-ium)tris(1,10-phenanthroline)heptaiodide], was prepared by one-step synthesis. Its formation is driven by hydrogen-bond assisted supramolecular assembly in the presence of chromium(iii) acetate. Its structure has been characterized by the means of single-crystal X-ray diffraction. To date, this is only one of the few examples of organized linear infinite polyiodides with a known structure. The interplay between the interactions within the hypervalent iodine chain and its supramolecular environment is elucidated. The electrical, thermal, and spectroscopic properties of the studied compound were investigated and associated with the structural features. The infinite character of the polyiodide chain and its similarity to the blue starch-iodine complex has been additionally confirmed by Raman spectroscopy. Despite the apparent structural and spectroscopic similarities with the previously reported 1D polymeric polyiodide, its physical properties, i.e. electrical conductivity and thermal stability, differ significantly. This can be rationalized by the differences in the orbital overlap within the iodine chain, as well as the distinct interactions with the cation.

An alternative approach to the Suzuki cross-coupling reaction is used to synthesize a series of new luminophores based on 4-alkyl-4 H -1,2,4-triazole cores conjugated via 1,4-phenylene linker to fused-bicyclic and tricyclic aromatic, or heteroaromatic arrangements. The described methodology allows one to conduct the coupling reaction with the use of commercially available boronic acids in the presence of conventional solvents or ionic liquids and produced excellent yields. It was found that the use of ultrasounds or microwaves significantly accelerates the reaction. The obtained compounds exhibited high luminescent properties and a large quantum yield of emitted photons. The X-ray molecular structures of three highly conjugated 4 H -1,2,4-triazole representatives are also presented.

Two different coordination compounds of copper were synthesized from the same building blocks (1,10-phenanthroline, bromoacetate anions, and copper cations). The synthesis parameters were carefully designed and evaluated to allow the change of the resulting compounds molecular structure, i.e., formation of mononuclear (bromoacetato- O , O ')(bromoacetato- O )aqua(1,10-phenanthroline- N , N ')copper(II) and dinuclear (μ-bromido-1:2κ 2 )bis(μ-bromoacetato-1κ O ,2κ O' )bis(1,10-phenanthroline- N , N ')dicopper(II) bromoacetate bromoacetic acid solvate. The crystal, molecular and supramolecular structures of the studied compounds were determined and evaluated in Hirshfeld analysis. The UV-Vis-IR absorption and thermal properties were studied and discussed. For the explicit determination of the influence of compounds structure on radiation absorption in UV-Vis range, density functional theory and time-dependent density functional theory calculations were performed.

Decreased exercise capacity (EC) is an established predictor of cardiac and all-cause mortality in patients with chronic heart failure (HF). No correlation has been found between EC and left ventricular (LV) ejection fraction. Moreover, data about the effect of right ventricular (RV) function on EC in HF with severe LV dysfunction are limited and contradictory. In this study, we aimed to investigate the relationship between EC and myocardial mechanics in patients with HF with reduced ejection fraction.Consecutive patients with symptomatic HF and LV ejection fraction ≤35% were prospectively assessed. All patients were evaluated with enhanced echocardiography. A symptom-limited treadmill cardiopulmonary exercise test (CPX) was performed within 24-hour interval. Patients were stratified into 4 groups according to their EC defined by Weber's classification. Prognosis of EC, expressed as oxygen uptake at peak exercise (peak VO2), was evaluated in multivariate linear regression analysis model.Sixty-seven patients with New York Heart Association classes II to III and a mean LV ejection fraction of 26 ± 7% were enrolled. A wide range of peak VO2 was observed in CPX with patient exercise performance distributed to all classes according to Weber's classification. Significant differences were found in RV systolic and diastolic functions between groups with different classes of EC: RV peak systolic myocardial velocity (S') (P < .001), tricuspid annular plane systolic excursion (TAPSE) (P = .003), RV E' (P = .003). In patients with functional decline, systolic pulmonary artery pressure (PASP) was higher (P = .029) and TAPSE/PASP ratio was lower (P = .006). No significant differences were found in LV diameter, systolic and diastolic function, and degree of mitral regurgitation. Thirty three patients with RV systolic dysfunction showed lower peak VO2 and oxygen uptake at anaerobic threshold (P = .008, P = .006, respectively), shorter exercise time (P = .003), and lower systolic blood pressure (P = .01) than in patients with normal RV systolic function. Logistic multivariate linear regression analysis with stepwise inclusion and exclusion revealed that gender, RV S', and RV free wall strain were independent predictors of peak VO2.RV function, assessed as S' and free wall strain, was independently related to EC, measured using CPX, in patients with HF and severe LV systolic dysfunction.

In the present paper, we describe a high sensitivity intensity fibre-optic displacement sensor with tens of picometre resolution combined with a sub-picometre resolution interferometric calibration system. Both integrated components form the so-called "2 in one ferrule" system 2iOF. The design and construction of the presented device depend on integrating two sensors' systems within one fibre-optic measuring head, which allows performing in situ calibration process with no additional time-consuming adjustment procedure. The resolution of the 2iOF system is 31 pm/Hz 1/2 obtained with an interferometric Fabry-Perot based calibration system-providing accuracy better than tens of fm/Hz 1/2 within 1 MHz bandwidth in the measurement range of up to 100 μm. The direct response from the intensity sensor is then the 2iOF output one. It is faster and more convenient to analyze in comparison, with much better resolution (3 orders of magnitude higher) but on the other hand also more time consuming and dependent on the absolute sample position interferometer. The proposed system is flexible and open to various applications. We will present the results of the piezoelectrical actuator displacement measurements, which were performed using the developed system.

We report on the design, properties, and applications of a high-resolution and wide-bandwidth light intensity fiber optic displacement sensor for microelectromechanical system (MEMS) metrology. There are two types of structures that the system is dedicated to: vibrating with both high and low frequencies. In order to ensure high-frequency and high-resolution measurements, frequency down mixing and selective signal processing were applied. The obtained effective measuring bandwidth ranges from single hertz to 1 megahertz. The achieved resolution presented here is 116  pm/Hz 1/2 and 138  pm/Hz 1/2 for low-frequency and high-frequency operation modes, respectively, whereas the measurement of static displacement is 100 μm.

Background: Anaesthetic drugs and internal electrical shock may alter the haemodynamic status of patients undergoing implantable cardioverter-defibrillator (ICD) testing. Comparative data on the mechanisms of etomidate and propofol-induced changes in haemodynamic parameters are inconsistent. Also the effects of ICD shock on haemodynamics have not been extensively studied., Aim: To compare the haemodynamic effects of etomidate and propofol as well as electrical shock during ICD testing in a prospective, randomised trial., Methods: The study group consisted of 63 consecutive patients (mean age 66 ± 10 years, 51 males) who underwent ICD testing. Haemodynamic parameters were measured using impedance cardiography (Task Force Monitor Systems, CNSystems, Austria) before and after injection of etomidate (n = 30) or propofol (n = 33) as well as immediately after internal defibrillation of ventricular fibrillation (VF). Parameters measured included heart rate, systolic (sBP), diastolic (dBP) and mean (mBP) blood pressure, stroke volume (SV), cardiac output (CO) and total peripheral resistance (TPR)., Results: Propofol significantly decreased the values of all measured parameters (sBP: 123.4 ± 17.1 vs. 106.3 ± 18 mm Hg, p < 0.0001; dBP: 83.7 ± 12.2 vs. 74.1 ± 13.8 mm Hg, p < 0.0001; mBP: 93.9 ± 13.1 vs. 81.1 ± 16.1 mm Hg, p < 0.0001; SV: 61.1 ± 19.3 vs. 56.4 ± 15.7 mL, p < 0.003; CO: 4.51 ± 1.07 vs. 4.17 ± 0.73 L/min, p < 0.003; and TPR: 1,735.8 ± 532.6 vs. 1,573.9 ± 390.5 dyn×s/cm⁵), whereas the only significant change following etomidate infusion was a decrease in SV (60.6 ± 11 vs. 56.8 ± 10 mL, p < 0.022). The propofol-induced changes were similar in patients with reduced (< 40%) vs. preserved (≥ 40%) left ventricular ejection fraction (LVEF) and in patients in heart failure NYHA class 0-II vs. class III-IV. Induction of VF and internal electrical shock did not cause major haemodynamic changes apart from significant, albeit very modest, drops in dBP and mBP (77 ± 2 vs. 72.9 ± 18 mm Hg, p < 0.002, and 85.2 ± 17 vs. 81.8 ± 20 mm Hg, p < 0.017, respectively). There were no complications during ICD testing., Conclusions: Propofol significantly decreased BP probably by both reducing CO and causing vasodilatation, whereas etomidate only slightly decreased dBP and mBP without affecting other parameters. Propofol-induced changes were independent of LVEF or NYHA class. Induction of VF and internal defibrillation did not cause clinically significant changes apart from very modest drops in dBP and mBP values.