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1.
This review is devoted to the structure, assembly and function of cuticle. The topics are discussed from the mechanical perspective and whenever the data are available a special attention is paid to the cuticle of perianth organs, i.e., sepals, petals or tepals. The cuticle covering these organs is special in both its structure and function and some of these peculiarities are related to the cuticle mechanics. In particular, strengthening of the perianth surface is often provided by a folded cuticle that functionally resembles profiled plates, while on the surface of the petal epidermis of some plants, the cuticle is the only integral continuous layer. The perianth cuticle is distinguished also by those aspects of its mechanics and development that need further studies. In particular, more investigations are needed to explain the formation and maintenance of cuticle folding, which is typical for the perianth epidermis, and also to elucidate the mechanical properties and behavior of the perianth cuticle in situ. Gaps in our knowledge are partly due to technical problems caused by very small thicknesses of the perianth cuticle but modern tools may help to overcome these obstacles.  相似文献   
2.
Psoriasis is a chronic, immune-mediated inflammatory disease that affects around 125 million people worldwide. Several studies concerning the gut microbiota composition and its role in disease pathogenesis recently demonstrated significant alterations among psoriatic patients. Certain parameters such as Firmicutes/Bacteroidetes ratio or Psoriasis Microbiome Index were developed in order to distinguish between psoriatic and healthy individuals. The “leaky gut syndrome” and bacterial translocation is considered by some authors as a triggering factor for the onset of the disease, as it promotes chronic systemic inflammation. The alterations were also found to resemble those in inflammatory bowel diseases, obesity and certain cardiovascular diseases. Microbiota dysbiosis, depletion in SCFAs production, increased amount of produced TMAO, dysregulation of the pathways affecting the balance between lymphocytes populations seem to be the most significant findings concerning gut physiology in psoriatic patients. The gut microbiota may serve as a potential response-to-treatment biomarker in certain cases of biological treatment. Oral probiotics administration as well as fecal microbial transplantation were most reported in bringing health benefits to psoriatic patients. However, the issue of psoriatic bacterial gut composition, its role and healing potential needs further investigation. Here we reviewed the literature on the current state of the relationship between psoriasis and gut microbiome.  相似文献   
3.
Numerous studies have confirmed the coexistence of oxidative stress and inflammatory processes. Long-term inflammation and oxidative stress may significantly affect the initiation of the neoplastic transformation process. Here, we describe the synthesis of a new series of Mannich base-type hybrid compounds containing an arylpiperazine residue, 1,3,4-oxadiazole ring, and pyridothiazine-1,1-dioxide core. The synthesis was carried out with the hope that the hybridization of different pharmacophoric molecules would result in a synergistic effect on their anti-inflammatory activity, especially the ability to inhibit cyclooxygenase. The obtained compounds were investigated in terms of their potencies to inhibit cyclooxygenase COX-1 and COX-2 enzymes with the use of the colorimetric inhibitor screening assay. Their antioxidant and cytotoxic effect on normal human dermal fibroblasts (NHDF) was also studied. Strong COX-2 inhibitory activity was observed after the use of TG6 and, especially, TG4. The TG11 compound, as well as reference meloxicam, turned out to be a preferential COX-2 inhibitor. TG12 was, in turn, a non-selective COX inhibitor. A molecular docking study was performed to understand the binding interaction of compounds at the active site of cyclooxygenases.  相似文献   
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5.
The objective of this study was to determine the effect of complexation of oxidised starch with mineral elements on its physicochemical properties. Corn starch was oxidised with sodium hypochlorite and, afterwards, modified with ions of potassium, magnesium and iron. Thus, native and modified starches were analysed for: contents of mineral elements, colour parameters (L*a*b*), water binding capacity and solubility in water at temperature of 60 and 80 °C. Thermodynamic characteristics of gelatinisation by DSC, molecular weight distribution by GPC, intrinsic viscosity and pasting properties by RVA were studied. The efficiency of incorporation of metal ions into oxidised corn starch was about 30%, 20% and 20% for potassium, magnesium and iron ions, respectively. The complexation with potassium ions caused the greatest changes in the molecular weight distribution and the intrinsic viscosity of starches and viscosity of starch pastes. Only modification of starch with iron ions affected the colour parameters of the starch. Incorporation of metal ions into starch resulted also in changes in its water binding capacity and solubility in water.  相似文献   
6.
Listeria monocytogenes is a pathogen responsible for severe cases of food poisoning. Listeria spp. strains occurring in soil and water environments may serve as a reservoir of resistance determinants for pathogenic L. monocytogenes strains. A large collection of Listeria spp. strains (155) isolated from natural, agricultural, and urban areas was screened for resistance to heavy metals and metalloids, and the presence of resistance determinants and extrachromosomal replicons. Of the tested strains, 35% were resistant to cadmium and 17% to arsenic. Sequence analysis of resistance plasmids isolated from strains of Listeria seeligeri and Listeria ivanovii, and the chromosome of L. seeligeri strain Sr73, identified a novel variant of the cadAC cadmium resistance efflux system, cadA6, that was functional in L. monocytogenes cells. The cadA6 cassette was detected in four Listeria species, including strains of L. monocytogenes, isolated from various countries and sources—environmental, food-associated, and clinical samples. This resistance cassette is harbored by four novel composite or non-composite transposons, which increases its potential for horizontal transmission. Since some cadAC cassettes may influence virulence and biofilm formation, it is important to monitor their presence in Listeria spp. strains inhabiting different environments.  相似文献   
7.
Microbiological denitrification of red beet juice   总被引:1,自引:0,他引:1  
The purpose of study was the determination of optimal conditions for red beet juice denitrification by Paracoccus denitrificans bacteria as well as the evaluation of the usefulness of microbiologically treated juice for the production of a natural colouring preparation for foods. Total reduction of nitrates was found during bacterial culturing at 25 and 30 °C, at an initial pH of 7.0-8.0 and juice osmotic pressure of 900-1100 mOsm/kg. Microbiological denitrification procedure affected colour, taste and aroma of the juice. However, the use of juice as food colouring and component was made feasible by acidification and partial evaporation of water together with volatile substances.  相似文献   
8.
Electrochemical impedance spectroscopy was used for the study of two-component lipid membranes. Phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were to be investigated, because of their presence in biological membranes. Capacitance values of pure components are 0.62 and 0.32 μF cm−2, respectively. The 1:1 complex was formed during formation of the PC-PE lipid membrane. Formation of the complex can explain the deviation from the additivity rule. This equilibrium was described by mathematical equations and was further verified experimentally. Adequate equations let us calculate such parameters as: capacitance of the complex molecule, area occupied by the complex molecule as well as the stability constant of the complex.  相似文献   
9.
An adsorption process of magnetite nanoparticles functionalized with aminated chitosan (Fe3O4-AChit) showing application potential in nanomedicine into cell membrane models was studied. The cell membrane models were formed using a Langmuir technique from three selected phospholipids with different polar head-groups as well as length and carbon saturation of alkyl chains. The research presented in this work reveals the existence of membrane model composition-dependent regulation of phospholipid-nanoparticle interactions. The influence of the positively charged Fe3O4-AChit nanoparticles on a Langmuir film stability, phase state, and textures is much greater in the case of these formed by negatively charged 1,2-dipalmitoyl-sn-glycero-3-phospho-rac-(1-glycerol) (DPPG) than those created by zwitterionic 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and 2-oleoyl-1-palmitoyl-sn-glycero-3-phosphocholine (POPC). The adsorption kinetics recorded during penetration experiments show that this effect is caused by the strongest adsorption of the investigated nanoparticles into the DPPG monolayer driven very likely by the electrostatic attraction. The differences in the adsorption strength of the Fe3O4-AChit nanoparticles into the Langmuir films formed by the phosphatidylcholines were also observed. The nanoparticles adsorbed more easily into more loosely packed POPC monolayer.  相似文献   
10.
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