The production of recombinant peptides is critical in biotechnology and medicine for treating a variety of diseases. Thus, there is an urgent need for the development of quick, scalable, and cost-effective recombinant protein expression strategies. This study optimizes induction conditions for an insulin precursor, an analog GLP-1 precursor, and a peptide for COVID-19 therapy expression in E. coli using the response surface method. Factors such as pH, temperature, induction time, isopropyl-β-D-thiogalactopyranoside concentration, and optical density significantly influence peptide productivity. Experimental validation supports the effectiveness of these models in predicting peptide yields under optimal conditions. The optimal induction conditions were determined as follows: temperature at 37 °C, pH of the medium 7.0-8.0, induction at the early logarithmic phase of growth, isopropyl-β-D-thiogalactopyranoside concentration of 0.05 mM, and induction time of 6 h. After model validation, the productivity of each peptide producer exceeded 3 g/L. The optimal conditions achieved peptide titers significantly higher than those previously reported, suggesting that this technique is a versatile cultivation technology for the efficient production of different recombinant peptides. In conclusion, our research enhances the understanding of how tailored cultivation conditions can optimize recombinant peptide production efficiency.

• Klíčová slova
• GLP- 1, Inclusion body, Insulin, Recombinant peptide, Response surface method, Soluble protein expression,
• Publikační typ
• časopisecké články MeSH

The paper introduces the concept of the rational design of a deployable humeral intramedullary nail plug based on a honeycomb structure used for the surgical treatment of humeral shaft fractures. The concept serves for to restore the axial alignment of bone fragments and to maintain stability via bone-nail friction and locking screws. The design nail plug was gained by optimisation process the Latin Hypercube Sampling Design algorithm and Multi-Objective Genetic Algorithm. It was shown that we can use statistical shape function combined by 3 D printing for designing of a new rationally designed implants.

• Klíčová slova
• Expandable implant, adaptive response surface method, additively-manufactured, intramedullary humerus nail,
• MeSH
• fraktury humeru * chirurgie   MeSH
• humerus chirurgie   MeSH
• intramedulární fixace fraktury * MeSH
• kostní hřeby MeSH
• lidé MeSH
• studie proveditelnosti MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Nowadays, titanium and its alloys are the most commonly used implantable materials. The surface topography and chemistry of titanium-based implants are responsible for osseointegration. One of the methods to improve biocompatibility of Ti implants is a modification with sodium hydroxide (NaOH) or 3-aminopropyltriethoxysilane (APTES). In the present study, anodic titanium dioxide (ATO) layers were electrochemically fabricated, and then immersed in a NaOH solution or in NaOH and APTES solutions. The functionalized samples were characterized by using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). All samples were examined as drug delivery systems and scaffolds for cell culturing. Based on the parameters of the fitted desorption-desorption-diffusion (DDD) model parameters, it was concluded that the modification with NaOH increased the amount of released ibuprofen and inhibited the release process. Osteoblast-like cell line (SAOS-2) was used to investigate the cell response on the non-modified and modified ATO samples. The MTS test and immunofluorescent staining were carried out to examine cell adhesion and proliferation. The data showed that the modification of nanoporous TiO2 layers with small molecules such as APTES enhanced metabolic activity of adhered cells compared with the non-modified and NaOH-modified TiO2 layers. In addition, the cells had a polygonal-like morphology with distinct projecting actin filaments and were well dispersed over the whole analyzed surface.

• Klíčová slova
• (3-Aminopropyl)triethoxysilane, Cell response, Drug delivery system, Surface modification, Titanium dioxide,
• MeSH
• buněčná adheze účinky léků   MeSH
• buněčné linie MeSH
• elektrochemické techniky MeSH
• elektrody MeSH
• hydroxid sodný chemie   MeSH
• lékové transportní systémy * MeSH
• lidé MeSH
• osteoblasty cytologie   účinky léků   MeSH
• poréznost MeSH
• povrchové vlastnosti MeSH
• proliferace buněk účinky léků   MeSH
• propylaminy chemie   MeSH
• silany chemie   MeSH
• titan chemie   MeSH
• velikost částic MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• amino-propyl-triethoxysilane MeSH Prohlížeč
• hydroxid sodný MeSH
• propylaminy MeSH
• silany MeSH
• titan MeSH
• titanium dioxide MeSH Prohlížeč

The main purpose of this research is to design a high-fatigue performance hoop wrapped compressed natural gas (CNG) composite cylinder. To this end, an optimization algorithm was presented as a combination of finite element simulation (FES) and response surface analysis (RSA). The geometrical model was prepared as a variable wall-thickness following the experimental measurements. Next, transient dynamic analysis was performed subjected to the refueling process, including the minimum and maximum internal pressures of 20 and 200 bar, respectively. The time histories of stress tensor components were extracted in the critical region. Furthermore, RSA was utilized to investigate the interaction effects of various polymer composite shell manufacturing process parameters (thickness and fiber angle) on the fatigue life of polymer composite CNG pressure tank (type-4). In the optimization procedure, four parameters including wall-thickness of the composite shell in three different sections of the CNG tank and fiber angle were considered as input variables. In addition, the maximum principal stress of the component was considered as the objective function. Eventually, the fatigue life of the polymer composite tank was calculated using stress-based failure criterion. The results indicated that the proposed new design (applying optimal parameters) leads to improve the fatigue life of the polymer composite tank with polyethylene liner about 2.4 times in comparison with the initial design.

• Klíčová slova
• fatigue life, finite element simulation, gas tanks for vehicles, optimization, polymer composite tank, response surface analysis, type-4 CNG tank,
• Publikační typ
• časopisecké články MeSH

L-asparaginase is an essential enzyme used in cancer treatment, but its production faces challenges like low yield, high cost, and immunogenicity. Recombinant production is a promising method to overcome these limitations. In this study, response surface methodology (RSM) was used to optimize the production of L-asparaginase 1 from Saccharomyces cerevisiae in Escherichia coli K-12 BW25113. The Box-Behnken design (BBD) was utilized for the RSM modeling, and a total of 29 experiments were conducted. These experiments aimed to examine the impact of different factors, including the concentration of isopropyl-b-LD-thiogalactopyranoside (IPTG), the cell density prior to induction, the duration of induction, and the temperature, on the expression level of L-asparaginase 1. The results revealed that while the post-induction temperature, cell density at induction time, and post-induction time all had a significant influence on the response, the post-induction time exhibited the greatest effect. The optimized conditions (induction at cell density 0.8 with 0.7 mM IPTG for 4 h at 30 °C) resulted in a significant amount of L-asparaginase with a titer of 93.52 μg/mL, which was consistent with the model-based prediction. The study concluded that RSM optimization effectively increased the production of L-asparaginase 1 in E. coli, which could have the potential for large-scale fermentation. Further research can explore using other host cells, optimizing the fermentation process, and examining the effect of other variables to increase production.

• Klíčová slova
• Escherichia coli, Saccharomyces cerevisiae, Cancer treatment, L-asparaginase, Recombinant production, Response surface methodology (RSM),
• MeSH
• asparaginasa * genetika   biosyntéza   metabolismus   MeSH
• Escherichia coli K12 genetika   enzymologie   MeSH
• Escherichia coli genetika   metabolismus   MeSH
• fermentace MeSH
• isopropylthiogalaktosid farmakologie   MeSH
• rekombinantní proteiny * genetika   metabolismus   MeSH
• Saccharomyces cerevisiae * genetika   metabolismus   MeSH
• teplota MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• asparaginasa * MeSH
• isopropylthiogalaktosid MeSH
• rekombinantní proteiny * MeSH

Response surface methodology was used to evaluate the effect of main variables such as concentration of galactose, yeast extract and wheat bran on alpha-galactosidase production from Aspergillus parasiticus MTCC-2796 under submerged fermentation conditions. A full factorial Central Composite Design was applied to study these main factors that affected alpha-galactosidase production. The experimental results showed that the optimum concentration of galactose, yeast extract and wheat bran were 1.5 %, 0.06 % and 1.5 %, respectively. This method was efficient as only 20 experiments were necessary to asses these conditions, and model adequacy was very satisfactory as the coefficient of determination was 0.9921.

• MeSH
• alfa-galaktosidasa biosyntéza   MeSH
• Aspergillus enzymologie   MeSH
• bioreaktory * MeSH
• fermentace fyziologie   MeSH
• kultivační média chemie   MeSH
• povrchové vlastnosti MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• Názvy látek
• alfa-galaktosidasa MeSH
• kultivační média MeSH

This review aims to describe a novel method in the field of electromyography (EMG), established and improved upon in the last three decades that is able to observe specific parameters of muscle units (MUs). This concept is called the decomposition method, based on its ability to decompose a surface EMG signal to describe muscle activity on the level of individual muscle units in contrast to the level of the whole muscle, as is customary for regular surface electromyography. We provide a brief overview of its history, constituent parts regarding both hardware and software and possible applications. We also acknowledge the state of the research, regarding the background of the decomposition algorithm, the main software component responsible for identifying individual motor units and their parameters. As a result of the ability to describe the behavior of individual motor units during muscle contractions, key concepts in neuromuscular physiology have been put forward, pertaining to the hierarchy of MUs during their recruitment. Together with the recent application for cyclic contractions and gait, the decomposition method is beginning to open up wider possibilities of enquiry.

• MeSH
• algoritmy MeSH
• elektromyografie * metody   MeSH
• kosterní svaly * fyziologie   MeSH
• lidé MeSH
• motorické neurony fyziologie   MeSH
• počítačové zpracování signálu MeSH
• recruitment (neurofyziologie) * fyziologie   MeSH
• svalová kontrakce * fyziologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

We analyzed the influence of parameters of deep levels in the bulk and conditions on the surface on transient charge responses of semi-insulating samples (CdTe and GaAs). We studied the dependence on the applied bias step used for the experimental evaluation of resistivity in contactless measurement setups. We used simulations based on simultaneous solutions of 1D drift diffusion and Poisson's equations as the main investigation tool. We found out that the resistivity can be reliably determined by the transient contactless method in materials with a large density of deep levels in the bulk (e.g., semi-insulating GaAs) when the response curve is described by a single exponential. In contrast, the materials with the low deep-level density, like semiconductor radiation detector materials (e.g., CdTe, CdZnTe, etc.), usually exhibit a complex response to applied bias, depending on the surface conditions. We show that a single exponential fit does not represent the true relaxation time and resistivity, in this case. A two-exponential fit can be used for a rough estimate of bulk material resistivity only in a limit of low-applied bias, when the response curve approaches a single-exponential shape. A decreasing of the bias leads to a substantially improved agreement between the evaluated and true relaxation time, which is also consistent with the approaching of the relaxation curve to the single-exponential shape.

• Klíčová slova
• CdTe, contactless resistivity, nonexponential response, surface defects,
• Publikační typ
• dopisy MeSH

Living organisms interact with various chemical compounds via receptors, which is described by the receptor theory. The affinity of the biologically active compounds toward receptors and their ability to trigger a biological or toxic signal vary substantially. In this work, we describe a new insight into understanding of the mode of action of receptor partial agonists and the receptor theory using a Full Logistic Model (FLM) of mixture toxicology. We describe the hypothesis that the effect of a partial agonist can be mathematically described via separation of agonistic and antagonistic behavior of the partial agonist where the antagonistic effect is described as an action of the compound producing zero effect. In this way, a competitive antagonist can be considered as an agonist with zero effect. This idea is also placed into a context with classical concepts, e.g., Gaddum's equation. Using the assumption that competitive antagonists are agonists with no effect, equations describing the microscopic and macroscopic equilibrium constants have been derived. Accordingly, we show that the constants could be calculated from the measured partial agonistic dose-response curve. As a consequence, we provide a simple mathematical tool for comparison of dose-response curves of drugs according to their affinities and efficacies.

• Klíčová slova
• Drug potency, Efficacy, Equilibrium dissociation constant, Mixture toxicology, Partial agonist, Receptor theory,
• MeSH
• biologické modely * MeSH
• lékové interakce * MeSH
• logistické modely * MeSH
• receptory buněčného povrchu metabolismus   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• receptory buněčného povrchu MeSH

In this work we discuss how sample surface topography can significantly influence the laser ablation (LA) process and, in turn, the analytical response of the LA Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) method. Six different surface topographies were prepared on a certified aluminium alloy sample BAM 311 and SRM NIST 610 to investigate the phenomenon. All the samples were repetitively measured by LA-ICP-MS using a spot by spot analysis. The effect of laser fluence in the range of 1-13 J/cm2 was studied. For majority of measured isotopes, the ICP-MS signal was amplified with roughening of the sample surface. A stronger effect was observed on the Al alloy sample, where the more than sixty-time enhancement was achieved in comparison to the polished surface of the sample. Since the effect of surface topography is different for each analyte, it can be stated that surface properties affect not only the ICP-MS response, but also elemental fractionation in LA. The presented results show that different surface topographies may lead to misleading data interpretation because even when applying ablation preshots, the signal of individual elements changes. The utmost care must be taken when preparing the surface for single shot analysis or chemical mapping. On the other hand, by roughening the sample surface, it is possible to significantly increase the sensitivity of the method for individual analytes and supress a matrix effect.

• Klíčová slova
• Fractionation, LA-ICP-MS, Laser ablation, Surface analysis, Surface topography,
• Publikační typ
• časopisecké články MeSH