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931.
932.
Irina A. Paun Bogdan S. Calin Cosmin C. Mustaciosu Eugenia Tanasa Antoniu Moldovan Agata Niemczyk Maria Dinescu 《International journal of molecular sciences》2021,22(11)
We report the design and fabrication by laser direct writing via two photons polymerization of innovative hierarchical structures with cell-repellency capability. The structures were designed in the shape of “mushrooms”, consisting of an underside (mushroom’s leg) acting as a support structure and a top side (mushroom’s hat) decorated with micro- and nanostructures. A ripple-like pattern was created on top of the mushrooms, over length scales ranging from several µm (microstructured mushroom-like pillars, MMP) to tens of nm (nanostructured mushroom-like pillars, NMP). The MMP and NMP structures were hydrophobic, with contact angles of (127 ± 2)° and (128 ± 4)°, respectively, whereas flat polymer surfaces were hydrophilic, with a contact angle of (43 ± 1)°. The cell attachment on NMP structures was reduced by 55% as compared to the controls, whereas for the MMP, a reduction of only 21% was observed. Moreover, the MMP structures preserved the native spindle-like with phyllopodia cellular shape, whereas the cells from NMP structures showed a round shape and absence of phyllopodia. Overall, the NMP structures were more effective in impeding the cellular attachment and affected the cell shape to a greater extent than the MMP structures. The influence of the wettability on cell adhesion and shape was less important, the cellular behavior being mainly governed by structures’ topography. 相似文献
933.
Fedorova Irina; Alvheim Anita R.; Hussein Nahed; Salem Norman Jr. 《Canadian Metallurgical Quarterly》2009,123(6):1218
Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) may be biosynthesized from a precursor α-linolenic acid (LNA) or obtained preformed in the diet. Dams were fed four diets with different levels of the various n-3 fatty acids during pregnancy and lactation, and their offspring were weaned to the same diets: “n-3 Deficient,” containing (as % total fatty acids) 0.07% of LNA; “Low LNA” (0.4%); “High LNA” (4.8%); and a “DHA + EPA” diet, containing 0.4% of LNA, 2% DHA, and 2% EPA. Sensorimotor gating was measured by prepulse inhibition (PPI) of the acoustic startle response in C57Bl6 mice. The n-3 Deficient and Low LNA diets caused a substantial deficit in PPI compared to the DHA + EPA diet, whereas the High LNA diet induced a less pronounced, but significant reduction of PPI. These are the first data that demonstrate a deficit in sensorimotor gating in rodents caused by an inadequate amount of the n-3 fatty acids in the diet. Our results differentiate the effects of a High LNA diet from one with added EPA and DHA even though the difference in brain DHA content is only 12% between these dietary groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
934.
Sonja Ellen Lobo Francisco Henrique Lanna Wykrota Ana Carolina Marques Barbosa Oliveira Irina Kerkis Germán Bohorquez Mahecha Humberto José Alves 《Journal of materials science. Materials in medicine》2009,20(5):1137-1147
Biphasic bioceramics have been widely indicated for bone reconstruction; however, the real gain in bone mass due to the presence
of such biomaterials has not been established yet nor the advantages of its association with platelet concentrate. This study
aims at quantifying the volume of bone matrix, osteoblasts, osteocytes, blood vessels and adipose tissue after the application
of a biphasic bioceramics composed of 65% hydroxyapatite and 35% β-tricalcium phosphate. Critical-size bone defects were produced
in rabbit femora and reconstructed with bioceramics only, with bioceramics combined with platelet concentrate, with platelet
concentrate alone, and with no treatment (blood clot). The quantitative evaluation was performed on histological sections
using histomorphometry. Our data provide original evidence that consolidates the indication of bioceramics for clinical bone
loss reconstruction. The application of biphasic bioceramics alone led to major bone mass gain and was followed by its association
with platelet concentrate. On the other hand, platelet concentrate can contribute to the augmentation and maintenance of the
adipose tissue, representing a new field for future applications in plastic surgery. 相似文献
935.
Alexander V. Fonin Sergey A. Silonov Olesya G. Shpironok Iuliia A. Antifeeva Alexey V. Petukhov Anna E. Romanovich Irina M. Kuznetsova Vladimir N. Uversky Konstantin K. Turoverov 《International journal of molecular sciences》2021,22(11)
In this work, we put forward a hypothesis about the decisive role of multivalent nonspecific interactions in the early stages of PML body formation. Our analysis of the PML isoform sequences showed that some of the PML isoforms, primarily PML-II, are prone to phase separation due to their polyampholytic properties and the disordered structure of their C-terminal domains. The similarity of the charge properties of the C-terminal domains of PML-II and PML-VI isoforms made it possible for the first time to detect migration of PML-VI from PML bodies to the periphery of the cell nucleus, similar to the migration of PML-II isoforms. We found a population of “small” (area less than 1 µm2) spherical PML bodies with high dynamics of PML isoforms exchange with nucleoplasm and a low fraction of immobilized proteins, which indicates their liquid state properties. Such structures can act as “seeds” of functionally active PML bodies, providing the necessary concentration of PML isoforms for the formation of intermolecular disulfide bonds between PML monomers. FRAP analysis of larger bodies of toroidal topology showed the existence of an insoluble scaffold in their structure. The hypothesis about the role of nonspecific multiple weak interactions in the formation of PML bodies is further supported by the change in the composition of the scaffold proteins of PML bodies, but not their solidification, under conditions of induction of dimerization of PML isoforms under oxidative stress. Using the colocalization of ALT-associated PML bodies (APBs) with TRF1, we identified APBs and showed the difference in the dynamic properties of APBs and canonical PML bodies. 相似文献
936.
Ivanova Irina I. Pomakhina Elena B. Rebrov Alexander I. Derouane Eric G. 《Topics in Catalysis》1998,6(1-4):49-59
13C MAS NMR study of the early stages of propane 2-13C activation was performed over H-ZSM-5 catalysts with various content of protonic and aprotonic sites. The reaction mechanism was tested by addition of various probe-molecules (C3H6, C6H6, H2, H2O and CO). The results on tracing the fate of 13C label during this experiments conclude to a monofunctional mechanism involving propane protonation on the strong Brønsted sites of H-ZSM-5 and the formation of carbonium ion type transition states, which further evolve in four different ways leading to 13C scrambling in propane, cracking, dehydrogenation and disproportionation. 相似文献
937.
A new approach for design of organic electrochromic devices with inter-digitated electrode structure
Galit Bar Galit Strum Raz Gvishi Nina Larina Vladimir Lokshin Vladimir Khodorkovsky Larissa Grinis Arie Zaban Irina Kiryuschev 《Solar Energy Materials & Solar Cells》2009,93(12):2118-8
We present a new approach for design of organic electrochromic devices (ECD) with inter-digitated electrode (IDE) structure and three-electrode dynamic operation. The advantages of the IDE design include the ability to produce fast and homogenous color change over large areas. In addition, it enables fabrication of multi-color devices. Our method involves photolithographic etching of ITO followed by electrophoretic deposition (EPD) and mechanical compression of porous titania to produce finely patterned electrodes with high surface area. The titania layer is chemically modified by new stable and reversible electrochromic viologen derivatives involving phenylphosphonic acid anchoring moiety. The new device demonstrates reversible and strong color change from colorless to deep blue and yellow. 相似文献
938.
Kataeva Irina A.; Blum David L.; Li Xin-Liang; Ljungdahl Lars G. 《Protein engineering, design & selection : PEDS》2001,14(3):167-172
Cellulolytic and hemicellulolytic enzymes usually have a domaincomposition. The mutual influence of a cellulose-binding domainand a catalytic domain was investigated with cellobiohydrolaseCelK and xylanase XynZ from Clostridium thermocellum. CelK iscomposed of an N-terminal family IV cellulose-binding domain(CBDIVCelK), a family 9 glycosyl hydrolase domain (Gh9CelK)and a dockerin domain (DD). CelK without the DD, (CBDIVGh9)CelKand CBDIVCelK bound cellulose. The thermostability of (CBDIVGh9)CelKwas significantly higher than that of CBDIVCelK and Gh9CelK.The temperature optima of (CBDIVGh9)CelK and Gh9CelKwere 65 and 45°C, respectively. XynZ consists of an N-terminalferuloyl esterase domain (FAEXynZ), a linker (L), a family VICBD (CBDVIXynZ), a DD and a xylanase domain. FAEXynZ and (FAELCBDVI)XynZ,used in the present study did not bind cellulose, but both werehighly thermostable. Replacement of CBDVIXynZ with CBDIVCelKresulted in chimeras with feruloyl esterase activity and theability to bind cellulose. CBDIVCelKFAEXynZ bound cellulosewith parameters similar to that of (CBDIVGh9)CelK. (FAEL)XynZCBDIVCelKand FAEXynZCBDIVCelK had lower relative affinities andbinding capacities than those of (CBDIVGh9)CelK. Thethree chimeras were much less thermostable than FAEXynZ and(FAELCBDVI)XynZ. The results indicate that domainsof glycosyl hydrolases are not randomly combined and that domaininteractions affect properties of these domain-structured enzymes. 相似文献
939.
Irina Shiyanovskaya Seth Green Asad Khan Greg Magyar Oleg Pishnyak J. William Doane 《Journal of the Society for Information Display》2008,16(1):113-115
Abstract— This paper demonstrates the first substrate‐free cholesteric liquid‐crystal displays. The encapsulated cholesteric displays are ultra‐thin (with a total thickness around 20 μm) and ultra‐lightweight (0.002 g/cm2). The displays exhibit unprecedented conformability, flexibility, and drapability while maintaining electro‐optical performance and mechanical integrity. All functional display layers are sequentially coated on a preparation substrate and then lifted‐off from the preparation substrate to form a free‐standing display. The display fabrication process, electro‐optical performance, and display flexibility are discussed. 相似文献
940.
Nutritional depletion in n‐3 PUFA in apoE knock‐out mice: A new model of endothelial dysfunction associated with fatty liver disease 下载免费PDF全文