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排序方式: 共有583条查询结果,搜索用时 15 毫秒
161.
Hana Sehadova Radka Zavodska Lenka Rouhova Michal Zurovec Ivo Sauman 《International journal of molecular sciences》2021,22(24)
Filippi’s glands (FGs), formerly also called Lyonet’s glands, are accessory secretory structures of the labial (silk) glands of lepidopteran caterpillars, which were implicated to play an important role in the maturation of the silk material and the construction of the cocoon. In our previous study, we have identified several species of giant silk moths that completely lack the FGs. Interestingly, the absence of FGs in these species correlates with the construction of a loose cocoon architecture. We investigated the functions of FGs by their surgical extirpation in the last instar larvae of the silkworm, Bombyx mori. We found that the absence of FGs altered the structure of the resulting cocoon, in which the different layers of silk were separated. In further experiments, we found no effects of the absence of FGs on larval cocoon formation behavior or on changes in cocoon mass or lipid content. Differential proteomic analysis revealed no significant contribution of structural proteins from FGs to silk cocoon material, but we identified several low abundance proteins that may play a role in posttranslational modifications of some silk proteins. Proteomic analysis also revealed a difference in phosphorylation of the N-terminal sequence of fibroin-heavy chain molecule. Thus, FGs appear to affect silk stickiness during spinning by regulating posttranslational modifications. This could also explain the link that exists between the absence of these glands and the formation of loose cocoons in some giant silk moth species. 相似文献
162.
Dispersing agents are used during the manufacture of disperse dyes to ensure standard dyeing properties. Polymeric dispersing agents have advantages over classical dispersants in that they are are colourless and easily degraded and do not have to be present in such large quantities. Redispersibility is a potential problem and we have therefore investigated the redispersibility of CI Disperse Red 60 (pure colorant) achieved with classical and polymeric dispersants. We have developed a calculation procedure that will provide some basis characteristics of the studied system and make it possible to choose the composition of mixture of components used for preparation of disperse dye at which the relative coefficient of redispersibility (Kr) is optimised. We found that the Krof dye prepared with classical dispersants was 10–40 while that of dye prepared with polymeric dispersant was 0.05–7.0. 相似文献
163.
Marian Rupert Anirban Bhattacharya Vendula Tvrdonova Stillerova Marie Jindrichova Audrey Mokdad Eric Bou-Grabot Hana Zemkova 《International journal of molecular sciences》2020,21(22)
Activation of the P2X7 receptor results in the opening of a large pore that plays a role in immune responses, apoptosis, and many other physiological and pathological processes. Here, we investigated the role of conserved and unique residues in the extracellular vestibule connecting the agonist-binding domain with the transmembrane domain of rat P2X7 receptor. We found that all residues that are conserved among the P2X receptor subtypes respond to alanine mutagenesis with an inhibition (Y51, Q52, and G323) or a significant decrease (K49, G326, K327, and F328) of 2′,3′-O-(benzoyl-4-benzoyl)-ATP (BzATP)-induced current and permeability to ethidium bromide, while the nonconserved residue (F322), which is also present in P2X4 receptor, responds with a 10-fold higher sensitivity to BzATP, much slower deactivation kinetics, and a higher propensity to form the large dye-permeable pore. We examined the membrane expression of conserved mutants and found that Y51, Q52, G323, and F328 play a role in the trafficking of the receptor to the plasma membrane, while K49 controls receptor responsiveness to agonists. Finally, we studied the importance of the physicochemical properties of these residues and observed that the K49R, F322Y, F322W, and F322L mutants significantly reversed the receptor function, indicating that positively charged and large hydrophobic residues are important at positions 49 and 322, respectively. These results show that clusters of conserved residues above the transmembrane domain 1 (K49–Y51–Q52) and transmembrane domain 2 (G326–K327–F328) are important for receptor structure, membrane expression, and channel gating and that the nonconserved residue (F322) at the top of the extracellular vestibule is involved in hydrophobic inter-subunit interaction which stabilizes the closed state of the P2X7 receptor channel. 相似文献
164.
Neamul H. Khansur Udo Eckstein Matej Sadl Hana Ursic Kyle G. Webber 《Journal of the American Ceramic Society》2020,103(1):43-47
A novel technique for the rapid room-temperature deposition of porous ceramic, glass, or metal thick films using the aerosol deposition (AD) method is presented. The process is based on the co-deposition of the desired film material and a second water-soluble constituent, resulting in a ceramic-ceramic composite. Following the subsequent removal of water-soluble end member, a network of pores is retained. To demonstrate the process, porous BaTiO3 thick films were fabricated through co-deposition with NaCl. Microstructural images show the clear development of a porous structure, which was found to enhance the dielectric properties over dense thick films, possibly related to the lower extent of internal residual stress. This simple but highly effective porous structure fabrication can be applied to any film and substrate material stable in water and is promising for the application of AD-processed films in gas sensors, solid oxide fuel cells, and humidity sensors. 相似文献
165.
Hana Lee Donghyun Hwang Minjoo Lee Jinho Lee Seungkwan Cho Tack-Joong Kim Han Sung Kim 《International journal of molecular sciences》2022,23(5)
Acne is a common inflammatory disorder of the human skin and a multifactorial disease caused by the sebaceous gland and Propionibacterium acnes (P. acnes). This study aimed to evaluate the anti-inflammatory effect of micro-current stimulation (MC) on peptidoglycan (PGN)-treated raw 264.7 macrophages and P. acnes-induced skin inflammation. To specify the intensity with anti-inflammatory effects, nitric oxide (NO) production was compared according to various levels of MC. As the lowest NO production was shown at an intensity of 50 μA, subsequent experiments used this intensity. The changes of expression of the proteins related to TLR2/NF-κB signaling were examined by immunoblotting. Also, immunofluorescence analysis was performed for observing NF-κB p65 localization. All of the expression levels of proteins regarding TLR2/NF-κB signaling were decreased by the application of MC. Moreover, the application of MC to PGN-treated raw 264.7 cells showed a significant decrease in the amount of nuclear p65-protein. In the case of animal models with P. acnes-induced skin inflammation, various pro-inflammatory cytokines and mediators significantly decreased in MC-applied mice. In particular, the concentration of IL-1β in serum decreased, and the area of acne lesions, decreased from the histological analysis. We suggest for the first time that MC can be a novel treatment for acne. 相似文献
166.
S. Souentie A. Hammad S. Brosda G. Foti C. G. Vayenas 《Journal of Applied Electrochemistry》2008,38(8):1159-1170
The reduction of NO by C2H4 in high excess of O2 and temperatures 200−300 °C was investigated using a monolithic electropromoted reactor (MEPR) with twenty-two Rh/YSZ/Pt
parallel plate elements. It was found that at 220–240 °C and 10% O2 the selective catalytic reduction (SCR) of NO can be electropromoted by 450% with near 100% selectivity to N2 and ΛNO values up to 2.4. The corresponding rate enhancement ratio of complete C2H4 oxidation is up to 900% with Faradaic efficiency,
, values up to 350. The system appears promising for practical applications. 相似文献
167.
Hana Mtnkov Gilles Mailhot Jaromír Jirkovský Josef Krýsa Michle Bolte 《Applied catalysis. B, Environmental》2005,57(4):257-265
Kinetics of oxidative photodegradation of Monuron (3-(4-chlorophenyl)-1,1-dimethylurea) in different photocatalytic systems (iron, TiO2 and combined system iron + TiO2) were investigated and compared. The influence of iron addition on TiO2 photocatalyst and of TiO2 on the photocatalytic cycle Fe(III)/Fe(II) were carefully studied. A very positive effect of iron addition was observed. This phenomenon was more and more pronounced when TiO2 concentration was lower. In a suspension of TiO2 (24 mg L−1) with addition of Fe(III) (3 × 10−4 mol L−1) the measured rate constant was similar to that obtained in a suspension of TiO2 with a concentration more than 20 times higher (500 mg L−1). The mechanistic approach carried out in this study allows us to identify the main reactions governing the combined system and a photochemical cycle was proposed. The optimisation of the photocatalytic systems was obtained when each photocatalyst plays a specific role: Fe(III) as a main OH radicals source and TiO2 as an oxidizing agent of Fe(II). 相似文献
168.
Tomas Strharsky Dominika Pindjakova Jiri Kos Lucia Vrablova Hana Michnova Jan Hosek Nicol Strakova Veronika Lelakova Lenka Leva Lenka Kavanova Michal Oravec Alois Cizek Josef Jampilek 《International journal of molecular sciences》2022,23(6)
A series of eighteen 4-chlorocinnamanilides and eighteen 3,4-dichlorocinnamanilides were designed, prepared and characterized. All compounds were evaluated for their activity against gram-positive bacteria and against two mycobacterial strains. Viability on both cancer and primary mammalian cell lines was also assessed. The lipophilicity of the compounds was experimentally determined and correlated together with other physicochemical properties of the prepared derivatives with biological activity. 3,4-Dichlorocinnamanilides showed a broader spectrum of action and higher antibacterial efficacy than 4-chlorocinnamanilides; however, all compounds were more effective or comparable to clinically used drugs (ampicillin, isoniazid, rifampicin). Of the thirty-six compounds, six derivatives showed submicromolar activity against Staphylococcus aureus and clinical isolates of methicillin-resistant S. aureus (MRSA). (2E)-N-[3,5-bis(trifluoromethyl)phenyl]- 3-(4-chlorophenyl)prop-2-enamide was the most potent in series 1. (2E)-N-[3,5-bis(Trifluoromethyl)phenyl]-3-(3,4-dichlorophenyl)prop-2-enamide, (2E)-3-(3,4-dichlorophenyl)-N-[3-(trifluoromethyl)phenyl]prop-2-enamide, (2E)-3-(3,4-dichloro- phenyl)-N-[4-(trifluoromethyl)phenyl]prop-2-enamide and (2E)-3-(3,4-dichlorophenyl)- N-[4-(trifluoromethoxy)phenyl]prop-2-enamide were the most active in series 2 and in addition to activity against S. aureus and MRSA were highly active against Enterococcus faecalis and vancomycin-resistant E. faecalis isolates and against fast-growing Mycobacterium smegmatis and against slow-growing M. marinum, M. tuberculosis non-hazardous test models. In addition, the last three compounds of the above-mentioned showed insignificant cytotoxicity to primary porcine monocyte-derived macrophages. 相似文献
169.
Chunlu Liu Amin Hammad & Yoshito Itoh 《Computer-Aided Civil and Infrastructure Engineering》1997,12(6):431-443
The solution methods of multiobjective optimization have undergone constant development over the past three decades. However, the methods available to date are not particularly robust. Because of the complicated relationship between the rehabilitation cost and deterioration degree of infrastructure systems, it is difficult to find a near‐optimal solution using common optimization methods. Since genetic algorithms work with a population of points, they can capture a number of solutions simultaneously and easily incorporate the concept of Pareto optimality. In this paper a simple genetic algorithm with two additional techniques, Pareto optimality ranking and fitness sharing, is implemented for the deck rehabilitation plan of network‐level bridges, aiming to minimize the total rehabilitation cost and deterioration degree. This approach is illustrated by a simple example and then applied to a practical bridge system with a large number of bridges. 相似文献
170.
In this work we present a verification methodology for real-time distributed systems, based on their modular decomposition into processes. Given a distributed system, each of its components is reduced by abstracting away from details that are irrelevant for the required specification. The abstract components are then composed to form an abstract system to which a model checking procedure is applied. The abstraction relation and the specification language guarantee that if the abstract system satisfies a specification, then the original system satisfies it as well.The specification languageRTL is a branching-time version of the real-time temporal logicTPTL presented in Alur and Henzinger [1]. Its model checking is linear in the size of the system and exponential in the size of the formula. Two notions of abstraction for real-time systems are introduced, each preserving a sublanguage ofRTL. 相似文献