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991.
Paulina Czaplewska Aleksandra E. Bogucka Natalia Musia Dmitry Tretiakow Andrzej Skorek Dominik Stodulski 《Molecules (Basel, Switzerland)》2021,26(21)
Our studies aimed to explore the protein components of the matrix of human submandibular gland sialoliths. A qualitative analysis was carried out based on the filter aided sample preparation (FASP) methodology. In the protein extraction process, we evaluated the applicability of the standard demineralization step and the use of a lysis buffer containing sodium dodecyl sulfate (SDS) and dithiothreitol (DTT). The analysis of fragmentation spectra based on the human database allowed for the identification of 254 human proteins present in the deposits. In addition, the use of multi-round search in the PEAKS Studio program against the bacterial base allowed for the identification of 393 proteins of bacterial origin present in the extract obtained from sialolith, which so far has not been carried out for this biological material. Furthermore, we successfully applied the SWATH methodology, allowing for a relative quantitative analysis of human proteins present in deposits. The obtained results correlate with the classification of sialoliths proposed by Tretiakow. The performed functional analysis allowed for the first time the selection of proteins, the levels of which differ between the tested samples, which may suggest the role of these proteins in the calcification process in different types of sialoliths. These are preliminary studies, and drawing specific conclusions requires research on a larger group, but it provides us the basis for the continuation of the work that has already begun. 相似文献
992.
Summary: N-isopropylacrylamide (NIPAAm)/butylacrylate (BAc) copolymer was synthesized by emulsion polymerization in order to use it as a cell culture surface for corneal epithelium biosubstitutes. Results showed that the obtained polymers were thermosensitive hydrogels. The copolymer was characterized by Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and swelling degree. 3T3 Swiss cells were used as feeder layers and they were used to test the cytotoxic effect of the hydrogels. The conditions to isolate, cultivate, expand and cryo-preserve human oral mucosal cells were established and analysis of several morphological and immuno-histochemical characteristics of the cultivated oral mucous were made. 相似文献
993.
Barbara W. Chwirot Ma gorzata Kowalska Natalia Sypniewska Zbigniew Michniewicz Marcin Gra dziel 《Journal of photochemistry and photobiology. B, Biology》1999,50(2-3):174-183
Native fluorescence (autofluorescence) of human tissues can be a valuable source of diagnostic information for detecting premalignant and malignant lesions in the human body. Digital imaging of autofluorescence may be useful for localization of such lesions during endoscopic examinations. Tissue fluorescence of 31 adenomatous polyps obtained from 16 patients has been excited in vitro using the 325 nm line of a He-Cd laser. Digital images of the autofluorescence are recorded in six spectral bands. This study provides new data about the spatial distributions of autofluorescence intensities emitted in different spectral bands by colonic adenomatous lesions and normal colonic mucosa. Areas characterized by autofluorescence intensity lower than in normal mucosa are found for a majority of the polyps under study. The observed patterns of spatial distribution differ for the different spectral bands and for different polypoid lesions. No inverse correlation is found between the emission intensity and the thickness of colonic mucosa. The results indicate the spectral bands most useful for diagnostic applications and demonstrate the complexity of the optical processes involved in shaping both the spectra and intensities of the autofluorescence. 相似文献
994.
The methods for the determination of some heavy PAH in different objects by HPLC method with fluorescence detection have been developed. The following conditions for the separation of PAH have been chosen:The column 150 mm length, internal diameter 2.1 mm filled by reversible-phase sorbent Zorbax ODS (5 μ),mobile phase acetonutrile/water (80:20), the injected volume of sample concentrate 10 μ L, the velocity of mobile phase 200 μ L.min. The excitation region is 290-300 nm, the emission one is 350-420 nm. Under condition chosen the limit of detection are 5 pg for benz(a)pyrene,10 pg for pyrene and chrysene3 pg for benz(k)fluoranthene, and 20 pg for anthracene. The dynamic range is 3 order of magnitude. The reproducibility of peak highs is better than 5%. 相似文献
995.
Alexander Arest-Yakubovich Boris Nakhmanovich Irina Zolotareva Alexander Yakimansky Natalia Pakuro 《Macromolecular Symposia》2004,215(1):281-294
Organomagnesium compounds are well known initiators of anionic polymerization of polar monomers. However, we have found recently that in the presence of compounds with labile halogen atoms, e.g., benzyl chloride, they are also active initiators of cationic polymerization of isobutylene and styrene in hydrocarbon media. The tentative scheme of cationic initiation is suggested assuming the formation of benzyl cation connected with Mg2Cl5− counter-ion. The scheme is confirmed by quantum-chemical calculations and 1H NMR analysis of polyisobutylene. On addition of a polar monomer, N,N-dimethylacrylamide or 2-vinylpyridine, to Bu2Mg-BzCl-isobutylene polymerizing mixture, the former readily polymerizes. The mixture of homopolymers rather than block copolymers is formed in this case, however, this fact proves the co-existence of anionic and cationic centers in the system. 相似文献
996.
Maxim N. Sokolov Rita Hernndez‐Molina Danil N. Dybtsev Elena V. Chubarova Sergei F. Solodovnikov Natalia V. Pervukhina Cristian Vicent Rosa Llusar Vladimir Fedin 《无机化学与普通化学杂志》2002,628(11):2335-2339
Reaction of heterometal cuboidal clusters [Mo3(MCl)S4(H2O)9]3+ (M = Ni, Pd) with PhSO2Na in aqueous HCl leads to the substitution at Ni or Pd to give the [Mo3(M(PhSO2))(H2O)9—xClx](3—x)+species, isolated as supramolecular adducts with cucurbituril (Cuc) [Mo3(Ni(PhSO2))S4Cl1.17(H2O)7.83][Mo3(Ni(PhSO2))S4Cl2.22(H2O)6.78]Cl2.61 · Cuc · 15H2O ( 1 ) and [Mo3(Pd(PhSO2))S4Cl1.12(H2O)7.88][Mo3(Pd(PhSO2))S4Cl2.29(H2O)6.71]Cl2.59 · Cuc · 11H2O ( 2 ), respectively. Crystal structure of 1 and 2 was determined, revealing that the PhSO2 is coordinated via its sulfur atom (Ni — S 2.182 Å, Pd — S 2.305 Å). The structure of these isostructural compounds is built from triple aggregates {(cluster)(Cuc)(cluster)} united into zigzag chains via hydrogen bonds between coordinated PhSO2 and H2O ligands. 相似文献
997.
Romy Ettlinger Natalia Moreno Natalia Ziółkowska Aladin Ullrich Hans-Albrecht Krug von Nidda Daniel Jirák Kornelius Kerl Hana Bunzen 《Particle & Particle Systems Characterization》2020,37(12):2000185
Theragnostics represent a combination of therapy and diagnosis within one system. Herein, Fe3O4-ZIF-8 core–shell nanoparticles are developed and suggested as candidates for theragnostic applications in cancer treatment. A drug loaded metal–organic framework ZIF-8 (zeolitic imidazolate framework-8) represents the therapeutic tool, while the Fe3O4 core is included to enable the material visualization by magnetic resonance imaging (MRI). A reliable synthesis of Fe3O4-ZIF-8 core–shell nanoparticles of an average size below 100 nm is reported. The nanoparticles are characterized by FT-IR, TGA, XRPD, TEM, STEM-EDS, DLS, ICP-OES, CHN-elemental analysis, SQUID measurements, and MRI. Moreover, their chemical stability and in vitro cytotoxicity against fibroblast and selected cancer cell lines are evaluated. As a model drug, arsenic trioxide—a promising anticancer drug—is used. The drug release can be triggered by a pH change from 7.4 to 6.0 and the nanoparticles can be visualized by MRI in vitro, thus a potential theragnostic agent for cancer treatment is developed. 相似文献
998.
Natalia Afanasieva Edward Brame Alexander Korigodsky Tatiana Tupikova 《Macromolecular Symposia》1991,52(1):191-198
The results of systematic spectral studies of polymers in ophthalmology are presented. The spectral criteria of selection of intraocular lens (IOL; implants of long service in an organism have been defined for poly(methylphenylsiloxane). Non-inflammatory implantation of IOL, when the manufacturing of lenses is performed under spectral control at several stages, has been realized. New siloxane–polyurethane block copolymers promising for ophthalmology have been studied and passivated surfaces have been obtained. 相似文献
999.
1000.
Andrea Ciccioli Alessandro Latini Alessio Luongo Natalia N. Smirnova Alexey V. Markin Stefano Vecchio Ciprioti 《Entropy (Basel, Switzerland)》2022,24(2)
In the present study, the molar heat capacity of solid formamidinium lead iodide (CH5N2PbI3) was measured over the temperature range from 5 to 357 K using a precise automated adiabatic calorimeter. In the above temperature interval, three distinct phase transitions were found in ranges from 49 to 56 K, from 110 to 178 K, and from 264 to 277 K. The standard thermodynamic functions of the studied perovskite, namely the heat capacity C°p(T), enthalpy [H0(T) − H0(0)], entropy S0(T), and [G°(T) − H°(0)]/T, were calculated for the temperature range from 0 to 345 K based on the experimental data. Herein, the results are discussed and compared with those available in the literature as measured by nonclassical methods. 相似文献