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881.
Correlation Between Autofluorescence Intensity and Tumor Area in Mice Bearing Renal Cell Carcinoma 总被引:3,自引:2,他引:1
Bellini MH Coutinho EL Courrol LC Rodrigues de Oliveira Silva F Vieira Júnior ND Schor N 《Journal of fluorescence》2008,18(6):1163-1168
Protoporphyrin IX (PpIX) is a porphyrin derivative that is accumulated in cancerous tissue in consequence of the tumor-specific
metabolic alterations. The aim of this study was to evaluate the accumulation of PpIX in mice bearing renal cell carcinoma
by spectroscopy analysis. A total of 24 male Balb/c mice, 6 weeks old, were divided into six groups: Normal (without inoculation
of tumor cells) and 4, 8, 13, 16, and 20 days after inoculation of tumor cells. The orthotopic tumor model of renal cancer
was used. Murine renal cell carcinoma (Renca cells) were inoculated into the subcapsular space of the kidney. Normal and tumor-bearing
kidneys in different progression stages were removed and analyzed by ex-vivo spectroscopy and by microscopy, for tumor histometric
analysis. Emission spectra were obtained by exciting the samples at 405 nm. Significant differences between normal and tumor-bearing
kidneys in autofluorescence shape occurred in the 600–700 nm spectral region. A good correlation was found between emission
band intensity at 635 nm and the tumor area. 相似文献
882.
We use a simple Colour Glass Condensate/String Percolation Model argument to show the existence, due to energy conservation, of bounds to the violation of Feynman scaling and limiting fragmentation. 相似文献
883.
Dias CL Ala-Nissila T Karttunen M Vattulainen I Grant M 《Physical review letters》2008,100(11):118101
We elucidate the mechanism of cold denaturation through constant-pressure simulations for a model of hydrophobic molecules in an explicit solvent. We find that the temperature dependence of the hydrophobic effect induces, facilitates, and is the driving force for cold denaturation. The physical mechanism underlying this phenomenon is identified as the destabilization of hydrophobic contact in favor of solvent-separated configurations, the same mechanism seen in pressure-induced denaturation. A phenomenological explanation proposed for the mechanism is suggested as being responsible for cold denaturation in real proteins. 相似文献
884.
J. Roa-Rojas C. Salazar M. D. Llamosa P. A.A. Len-Vanegas D.A. Landínez Tllez P. Pureur F.T. Dias V.N. Vieira 《Journal of magnetism and magnetic materials》2008,320(14):e104-e106
We report synthesis and characterization of new Sr2TiMnO6 manganite-like material. Samples were produced by the solid state reaction method. X-ray diffraction experiments reveal the presence of peaks, which are characteristics of the complex perovskite systems. Rietveld refinement showed that Sr2TiMnO6 crystallizes in a tetragonal structure, which corresponds to the space group I/4m. From measurements of magnetization as a function of temperature, we determine the occurrence of magnetic ordering for a critical temperature TC=44.8 K and strong evidence of frustration. Curves of magnetization as a function of applied field show hysteretic behavior. Curves of polarization as a function of applied voltage exhibit the ferroelectric response of Sr2TiMnO6 material. Results reveal the occurrence of magnetoelectric response for the temperature regime T<44.8 K. 相似文献
885.
Massimo Curini Francesco Epifano MariaCarla Marcotullio Ornelio Rosati Yousheng Guan Ernest Wenkert 《Helvetica chimica acta》2000,83(4):755-759
The Kanematsu transformation was employed for the preparation of tetrahydroisobenzofuran‐4‐carboxylic acid ( 12 ), α‐methylation, subsequent conversion into the diazoethanone 14 , and, finally, treatment with dirhodium tetraacetate of which furnished the hydrindanone 1 of the steroid C‐D ring structure. 相似文献
886.
Riccardo Fontana Peggy Carla Raffaella Marconi Antonella Caputo Vasak B. Gavalyan 《Molecules (Basel, Switzerland)》2022,27(9)
Chitosan (CS) and its derivatives are receiving considerable attention for their great biocompatibility and broad-spectrum activities in many fields. In this work, we aimed to characterize the antimicrobial activity of novel chitosan Schiff bases (CSSB). CS was synthesized by double deacetylation of chitin (Cn) after its extraction from the armors of crustaceans Astacus leptodactylus, and CSSB-1 and CSSB-2 were synthesized by interaction of CS with 4-(2-chloroethyl) benzaldehyde (aldehyde-1) and 4-(bromoethyl) benzaldehyde (aldehyde-2), respectively, at room temperature. The synthesized compounds were characterized by elemental analysis, gel permeation chromatography (GPC), infrared spectroscopy (FTIR), thermogravimetry (TG), and differential scanning calorimetry (DSC). The antimicrobial activity against Gram-positive (Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa) bacteria and against yeasts (Candida albicans) was significantly increased due to their higher solubility as compared to unmodified CS opening perspectives for the use of these compounds for antimicrobial prevention in different fields as, for example, food industry, cosmetics, or restoration. 相似文献
887.
Carla Casadevall David Pascual Jordi Aragn Arnau Call Alicia Casitas Irene Casademont-Reig Julio Lloret-Fillol 《Chemical science》2022,13(15):4270
A catalytic system based on earth-abundant elements that efficiently hydrogenates aryl olefins using visible light as the driving-force and H2O as the sole hydrogen atom source is reported. The catalytic system involves a robust and well-defined aminopyridine cobalt complex and a heteroleptic Cu photoredox catalyst. The system shows the reduction of styrene in aqueous media with a remarkable selectivity (>20 000) versus water reduction (WR). Reactivity and mechanistic studies support the formation of a [Co–H] intermediate, which reacts with the olefin via a hydrogen atom transfer (HAT). Synthetically useful deuterium-labelled compounds can be straightforwardly obtained by replacing H2O with D2O. Moreover, the dual photocatalytic system and the photocatalytic conditions can be rationally designed to tune the selectivity for aryl olefin vs. aryl ketone reduction; not only by changing the structural and electronic properties of the cobalt catalysts, but also by modifying the reduction properties of the photoredox catalyst.A dual catalytic system based on earth-abundant elements reduces aryl olefins to alkanes in aqueous media under visible light. Mechanistic studies allow for rational tunning of the system for the selective reduction of aryl olefins vs ketones and vice versa. 相似文献
888.
889.
Patricia Ribeiro de Carvalho Frana Anna Carolina Pereira Lontra Patricia Dias Fernandes 《Molecules (Basel, Switzerland)》2022,27(13)
Endometriosis is a gynecological condition characterized by the growth of endometrium-like tissues inside and outside the pelvic cavity. The evolution of the disease can lead to infertility in addition to high treatment costs. Currently, available medications are only effective in treating endometriosis-related pain; however, it is not a targeted treatment. The objective of this work is to review the characteristics of the disease, the diagnostic means and treatments available, as well as to discuss new therapeutic options. 相似文献
890.
Valentina Di Iorio Stefano Boschi Cristina Cuni Manuela Monti Stefano Severi Giovanni Paganelli Carla Masini 《Molecules (Basel, Switzerland)》2022,27(13)
Since prostate cancer is the most commonly diagnosed malignancy in men, the theranostic approach has become very attractive since the discovery of urea-based PSMA inhibitors. Different molecules have been synthesized starting from the Glu-urea-Lys scaffold as the pharmacophore and then optimizing the linker and the chelate to improve functional characteristics. This article aimed to highlight the quality aspects, which could have an impact on clinical practice, describing the development of an Investigational Medicinal Product Dossier (IMPD) for clinical trials with [177Lu]Lu-PSMA-I&T in prostate cancer and other solid tumors expressing PSMA. The results highlighted some important quality issues of the final preparation: radiolabeling of PSMA-I&T with lutetium-177 needs a considerably longer time compared with the radiolabeling of the well-known [177Lu]Lu-PSMA-617. When the final product was formulated in saline, the stability of [177Lu]Lu-PSMA-I&T was reduced by radiolysis, showing a decrease in radiochemical purity (<95% in 24 h). Different formulations of the final product with increasing concentrations of ascorbic acid have been tested to counteract radiolysis and extend stability. A solution of 20 mg/mL of ascorbic acid in saline prevents radiolysis and ensures stability over 30 h. 相似文献