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121.
Flavonoid compounds are known for their antibacterial, anti-inflammatory, and anticancer properties. Therefore, they can influence membrane properties that interest us, modifying both their structure and functions. We used kaempferol (K) and myricetin (M) as representatives of this group. We investigated the influence of the abovementioned compounds on model cell membranes’ properties (i.e., Langmuir monolayers and liposomes). The basic research methods used in these studies were the Langmuir method with Brewster angle microscopy and microelectrophoresis. The π–A isotherms were registered for the pure components and mixtures of these compounds with phosphatidylcholine (PC) in appropriate volume ratios. Using mathematical equations, we established that kaempferol, myricetin, and the lipids formed complexes at 1:1 ratios. We derived the parameters characterizing the formed complexes, i.e., the surfaces occupied by the complexes and the stability constants of the formed complexes. Using the microelectrophoretic method, we determined the dependence of the lipid membranes’ surface charge density as a function of the pH (in the range of 2 to 10) of the electrolyte solution. The presented results indicate that the PC membrane’s modification with kaempferol or myricetin affected changes in the surface charge density and isoelectric point values.  相似文献   
122.
Nutritional value and physical and sensory quality characteristics of medium-grounded model canned meat products containing barley fibre preparation Vitacel BG300 (0.0%, 3.0% and 6.0%) were assessed. The results showed that regardless of the type of thermal treatment (pasteurisation and sterilisation), the addition of barley fibre did not significantly (P > 0.05) alter the content of the main nutrients (protein, fat and chlorides) in the block of canned meat product. Increasing the dose of barley fibre from 3.0% to 6.0% significantly increased (P < 0.05) the thermal loss in both pasteurised and sterilised canned meat products. The colour of the blocks of both pasteurised and sterilised canned meat products with barley fibre was significantly (P < 0.05) darker, and the instrumental hardness differed from the corresponding control products. Despite the beneficial nutritional effect of the Vitacel BG300 barley fibre preparation, its use significantly deteriorated the sensory quality of canned meat products.  相似文献   
123.
Heart failure (HF) is one of the major causes of morbidity and mortality worldwide and represents an escalating problem for healthcare systems. The identification of asymptomatic patients with underlying cardiac subclinical disease would create an opportunity for early intervention and prevention of symptomatic HF. Traditional biomarkers are very useful as diagnostic and prognostic tools in the cardiovascular field; however, their application is usually limited to overt cardiac disease. On the other hand, a growing number of studies is investigating the diagnostic and prognostic potential of new biomarkers, such as micro-RNAs (miRNA), long non-coding RNAs, and exosome cargo, because of their involvement in the early phases of cardiac dysfunction. Unfortunately, their use in asymptomatic phases remains a distant goal. The aim of this review is to gather the current knowledge of old and novel biomarkers in the early diagnosis of cardiac dysfunction in asymptomatic individuals.  相似文献   
124.
Novel bone substitutes such as highly porous ceramic scaffolds can serve as platforms for delivering active molecules. A common problem is to control the release of the drug, therefore, it is beneficial to use a drug-functionalized polymer coating. In this study, β-tricalcium phosphate-based porous scaffolds were obtained and coated with diclofenac-functionalized biopolymer – poly(3-hydroxyoctanoate) – P(3HO). To the best of our knowledge, studies using P(3HO) as a component in ceramic-polymer based drug delivery system for bone tissue regeneration have not yet been reported. Presented materials were comprehensively investigated by various techniques such as powder X-ray diffraction, scanning electron microscopy with energy dispersive spectroscopy, hydrostatic weighing and compression tests, pH and ionic conductivity measurements, high-performance liquid chromatography and in vitro cytotoxicity studies. The obtained diclofenac-loaded composite was not only characterised by controlled and sustained drug release, but also possessed improved mechanical properties. Moreover, the precipitation of apatite-like forms on its surface was observed after incubation in simulated body fluid, which indicates its bioactive potential. After 24 hours no cytotoxic effect on MC3T3-E1 mouse preosteoblastic cells was confirmed using indirect cytotoxicity studies. Thus, this promising multifunctional composite scaffold can be a promising candidate as an anti-inflammatory drug-delivery system in bone tissue engineering.  相似文献   
125.
The treatment of memory impairments associated with the central nervous system diseases remains an unmet medical need with social and economic implications. Here we show, that a multi-target ligand of aminergic G protein-coupled receptors with antipsychotic activity in vivo (D2AAK1) stimulates neuron growth and survival and promotes neuron integrity. We focused on the multilevel evaluation of the D2AAK1-related effects on neurons in terms of behavioral, cellular, molecular, and biochemical features in vivo and in vitro, such as memory-related responses, locomotor activity, tissue sections analysis, metabolic activity, proliferation level, neurons morphology, and proteins level involved in intracellular signaling pathways. In silico studies indicate that activation of calcium/calmodulin-dependent protein kinase I (CaMKI) may underline some of the observed activities of the compound. Furthermore, the compound increases hippocampal neuron proliferation via the activation of neurotrophic factors and cooperating signals responsible for cell growth and proliferation. D2AAK1 improves memory and learning processes in mice after both acute and chronic administration. D2AAK1 also causes an increase in the number of hippocampal pyramidal neurons after chronic administration. Because of its neuroprotective properties and pro-cognitive activity in behavioral studies D2AAK1 has the potential for the treatment of memory disturbances in neurodegenerative and mental diseases.  相似文献   
126.
Circular Economy (CE) is one of the approaches which are intensively developed and tested in different areas of industry and services. The aim of this solution is to use many kinds of resources in a closed flow and to achieve as a small amount of waste as it is possible.

One of the potential areas of using CE is Radio Frequency Identification (RFID). In RFID systems tags are utilized in various forms. This paper addresses investigation of a recycling process of RFID tags. Different attachment methods of these tags were tested and then, a recycling procedure was prepared based on the obtained results in which adhesives are recommended to be used as an attaching material between a tag and an identified object. The mentioned procedure was evaluated with using paper-face RFID tags. It was confirmed applicability of the proposed solution. Moreover, the conducted research revealed that an adhesion force of the adhesive layers in the prepared RFID tags decreased in the most extent during the first recycling cycle. It was found that in order to preserve a high adhesion force of these layers it is suggested to place the tags on a clean surface.  相似文献   

127.
In this study, the polyphenols content, α-amylase, α-glucosidase and cholinesterase-inhibiting activities of cloudy peach (Prunus persica) juices, were measured immediately after thermal treatment and after storage (6 months at 4 and 30 °C). The study showed that some cultivars were more useable for industry than others. Due to the high content of polyphenols and a high ability to inhibit enzymes linked to type 2 diabetes and Alzheimer's disease, noteworthy are the juices obtained from ‘Redheaven early’ and ‘Redheaven’ cultivars. The content of total phenolics ranged from 1109.7 to 390.7 mg/L of juice, and the dominant fraction was polymeric procyanidins. Following 6 months of storage a significant change was observed in the content of polyphenols, especially flavonols and anthocyanins. The data compiled from the conducted study indicate that peach juice could be useful for the juice industry as a promising source of bioactive compounds.  相似文献   
128.
The effect of the sodium alginate and methylcellulose modifiers on hydrolysis, setting reaction, microstructure, mechanical and in vitro properties of α-TCP based materials was investigated. It was found that the presence of sodium alginate impeded α-TCP hydrolysis to hydroxyapatite, which may have a significant influence on resorbability, biodegradation and biological behavior of biomaterials. There were several reasons for these phenomena, such as: (I) the gelation of sodium alginate in the presence of Ca2+, (II) the creation of an organic layer which impedes the diffusion of water molecules to α-TCP and (III) the uptake of water molecules by sodium alginate. The inhibitory effect was not observed for methylcellulose and it was diminished in simulated body fluid. Additionally, it was demonstrated that the examined cements varied in their microstructure, setting times and compressive strengths, depending on the applied kind of a polymer additive. The cement containing sodium alginate had a higher compressive strength (20 ± 8 MPa) than the one with methylcellulose (17 ± 4 MPa) and the one lacking polymer (14 ± 4 MPa). All the developed materials exhibited high bioactivity in vitro.  相似文献   
129.
The O-H...N and O-H...O hydrogen bonds were investigated in 10-hydroxybenzo[h]quinoline (HBQ) and benzo[h]quinoline-2-methylresorcinol complex in vacuo, solvent and crystalline phases. The chosen systems contain analogous donor and acceptor moieties but differently coupled (intra- versus intermolecularly). Car–Parrinello molecular dynamics (CPMD) was employed to shed light onto principle components of interactions responsible for the self-assembly. It was applied to study the dynamics of the hydrogen bonds and vibrational features as well as to provide initial geometries for incorporation of quantum effects and electronic structure studies. The vibrational features were revealed using Fourier transformation of the autocorrelation function of atomic velocity and by inclusion of nuclear quantum effects on the O-H stretching solving vibrational Schrödinger equation a posteriori. The potential of mean force (Pmf) was computed for the whole trajectory to derive the probability density distribution and for the O-H stretching mode from the proton vibrational eigenfunctions and eigenvalues incorporating statistical sampling and nuclear quantum effects. The electronic structure changes of the benzo[h]quinoline-2-methylresorcinol dimer and trimers were studied based on Constrained Density Functional Theory (CDFT) whereas the Electron Localization Function (ELF) method was applied for all systems. It was found that the bridged proton is localized on the donor side in both investigated systems in vacuo. The crystalline phase simulations indicated bridged proton-sharing and transfer events in HBQ. These effects are even more pronounced when nuclear quantization is taken into account, and the quantized Pmf allows the proton to sample the acceptor area more efficiently. The CDFT indicated the charge depletion at the bridged proton for the analyzed dimer and trimers in solvent. The ELF analysis showed the presence of the isolated proton (a signature of the strongest hydrogen bonds) only in some parts of the HBQ crystal simulation. The collected data underline the importance of the intramolecular coupling between the donor and acceptor moieties.  相似文献   
130.
Effect of rosemary (Rosmarinus officinalis L.) preparations in baked, vacuum-packed meatballs from chicken meat during 14 days of storage at +4 °C was assessed. The meatballs were divided into the following groups: RD−with 1.0% of dried spice, REE40 and REE70−with 2.0% of ethanol extracts: 40% (v/v) and 70% (v/v), respectively, and REO−with 0.1% of essential oil. The CONTROL product did not contain added rosemary. In chicken meatballs, the antioxidant stability was determined, microbiological analyses as well as sensory evaluation were performed. After 14 days of storage, the strongest antioxidant activity in the chicken meatballs exhibited rosemary ethanol extracts. Compared with the CONTROL, the REE70 and REO had the best microbiological quality at the end of the storage period. All products with rosemary were sensory acceptable; however, the highest scores in the evaluation of all sensory attributes were obtained by the RD treatment.  相似文献   
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