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排序方式: 共有633条查询结果,搜索用时 15 毫秒
1.
Daniel B. Moore Prof. Matt Beekman Dr. Sabrina Disch Dr. David C. Johnson 《Angewandte Chemie (International ed. in English)》2014,53(22):5672-5675
Telluride misfit layer compounds are reported for the first time. These compounds were synthesized using a novel approach of structurally designing a precursor that would form the desired product upon low‐temperature annealing, which allows the synthesis of kinetically stable products that do not appear on the equilibrium phase diagram. Four new compounds of the [(PbTe)1.17]m(TiTe2)n family are reported, and their structures were examined by a variety of X‐ray diffraction techniques. 相似文献
2.
Cover Picture: Absolute Configuration from Different Multifragmentation Pathways in Light‐Induced Coulomb Explosion Imaging (ChemPhysChem 16/2016) 下载免费PDF全文
Dr. Martin Pitzer Gregor Kastirke Dr. Maksim Kunitski Dr. Till Jahnke Dr. Tobias Bauer Christoph Goihl Florian Trinter Carl Schober Kevin Henrichs Jasper Becht Stefan Zeller Helena Gassert Markus Waitz Andreas Kuhlins Hendrik Sann Felix Sturm Florian Wiegandt Dr. Robert Wallauer Dr. Lothar Ph. H. Schmidt Allan S. Johnson Manuel Mazenauer Benjamin Spenger Sabrina Marquardt Sebastian Marquardt Prof. Dr. Horst Schmidt‐Böcking Prof. Dr. Jürgen Stohner Prof. Dr. Reinhard Dörner Dr. Markus Schöffler Prof. Dr. Robert Berger 《Chemphyschem》2016,17(16):2448-2448
3.
Christman KL Requa MV Enriquez-Rios VD Ward SC Bradley KA Turner KL Maynard HD 《Langmuir : the ACS journal of surfaces and colloids》2006,22(17):7444-7450
Micron and submicron-scale features of aldehyde functionality were fabricated in polymer films by photolithography to develop a platform for protein immobilization and assembly at a biologically relevant scale. Films containing the pH-reactive polymer poly(3,3'-diethoxypropyl methacrylate) and a photoacid generator (PAG) were patterned from 500 nm to 40 mum by exposure to 365 nm (i-line) light. Upon PAG activation and hydrolysis of acetals, aldehyde groups formed. After the films were incubated with a biotinylated aldehyde reactive probe, the X-ray photoelectron spectroscopy results were consistent with biotin being attached to the surface. The background was subsequently passivated by flood exposure and incubation with an aminooxy-terminated poly(ethylene glycol), resulting in a 98% reduction in nonspecific protein adsorption. Protein patterning and assembly was demonstrated using streptavidin, biotinylated anthrax toxin receptor-1, and the protective antigen moiety of anthrax toxin and confirmed by fluorescence microscopy and atomic force microscopy (AFM). AFM demonstrated that 500 nm protein features were achieved. Because of the abundance of biotinylated proteins, this methodology provides a platform for protein immobilization and assembly for various applications in biotechnology. 相似文献
4.
Lukas Fritz Dr. Sebastian Wienhold Sabrina Hackl Prof. Dr. Thorsten Bach 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(3):e202104064
A synthetic route to the pulvomycin class of natural products is presented, which culminated in the first synthesis of a pulvomycin, pulvomycin D. Key elements of the strategy include a pivotal aldol reaction which led to bond formation between the C24-C40 and the C8-C23 fragment. The remaining C1-C7 fragment was attached by a Yamaguchi esterification completing the assembly of the 40 carbon atoms within the main skeleton. Ring closure to the 22-membered lactone ring was achieved in the final stages of the synthesis by a Heck reaction. The completion of the synthesis required the removal of six silyl protecting groups in combination with olefin formation at C26-C27 by a Peterson elimination. 相似文献
5.
Sabrina Elkhanoufi Rachele Stefania Diego Alberti Simona Baroni Silvio Aime Prof. Simonetta Geninatti Crich 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(17):e202104563
The assessment of unregulated level of enzyme activity is a crucial parameter for early diagnoses in a wide range of pathologies. In this study, we propose the use of electron paramagnetic resonance (EPR) as an easy method to probe carboxylesterase (CE) enzymatic activity in vitro. For this application, were synthesized two amphiphilic, nitroxide containing esters, namely Tempo-C12 (T-C12) and Tempo-2-C12 (T-2-C12). They exhibit low solubility in water and form stable micelles in which the radicals are EPR almost silent, but the hydrolysis of the ester bond yields narrows and intense EPR signals. The intensity of the EPR signals is proportional to the enzymatic activity. CEs1, CEs2 and esterase from porcine liver (PLE) were investigated. The obtained results show that T-C12 and T-2-C12-containing systems display a much higher selectivity toward the CEs2, with a Limit of Detection of the same order of those ones obtained with optical methods. 相似文献
6.
Ribeiro Sabrina Dias Meneguin Andria Bagliotti Barud Hernane da Silva Silva Jhonatan Miguel Oliveira Rafael L. Asuno Rosana Maria Nascimento de Tormin Thiago Faria Muoz Rodrigo Alejandro Abarza Filho Guimes Rodrigues Ribeiro Clovis Augusto 《Journal of Thermal Analysis and Calorimetry》2022,147(13):7265-7275
Journal of Thermal Analysis and Calorimetry - Cellophane film production generates cellulosic residues from scraps, edges, and low-quality films. In this work, cellophane was used as a raw material... 相似文献
7.
Poor aqueous solubility of active compounds is a major issue in today’s drug delivery. In this study the smartFilm-technology was exploited to improve the dermal penetration efficacy of a poorly soluble active compound (curcumin). Results were compared to the dermal penetration efficacy of curcumin from curcumin bulk suspensions and nanocrystals, respectively. The smartFilms enabled an effective dermal and transdermal penetration of curcumin, whereas curcumin bulk- and nanosuspensions were less efficient when the curcumin content was similar to the curcumin content in the smartFilms. Interestingly, it was found that increasing numbers of curcumin particles within the suspensions increased the passive dermal penetration of curcumin. The effect is caused by an aqueous meniscus that is created between particle and skin if the dispersion medium evaporates. The connecting liquid meniscus causes a local swelling of the stratum corneum and maintains a high local concentration gradient between drug particles and skin. Thus, leading to a high local passive dermal penetration of curcumin. The findings suggest a new dermal penetration mechanism for active compounds from nano-particulate drug delivery systems, which can be the base for the development of topical drug products with improved penetration efficacy in the future. 相似文献
8.
Giustino Orlando Annalisa Chiavaroli Sabrina Adorisio Domenico V. Delfino Luigi Brunetti Lucia Recinella Sheila Leone Gokhan Zengin Alessandra Acquaviva Paola Angelini Giancarlo Angeles Flores Roberto Venanzoni Simonetta Cristina Di Simone Francesca Di Corpo Andrei Mocan Luigi Menghini Claudio Ferrante 《Molecules (Basel, Switzerland)》2021,26(15)
Prunus mahaleb L. fruit has long been used in the production of traditional liqueurs. The fruit also displayed scavenging and reducing activity, in vitro. The present study focused on unravelling peripheral and central protective effects, antimicrobial but also anti-COVID-19 properties exerted by the water extract of P. mahaleb. Anti-inflammatory effects were studied in isolated mouse colons exposed to lipopolysaccharide. Neuroprotection, measured as a blunting effect on hydrogen-peroxide-induced dopamine turnover, was investigated in hypothalamic HypoE22 cells. Antimicrobial effects were tested against different Gram+ and Gram- bacterial strains. Whereas anti-COVID-19 activity was studied in lung adenocarcinoma H1299 cells, where the gene expression of ACE2 and TMPRSS2 was measured after extract treatment. The bacteriostatic effects induced on Gram+ and Gram- strains, together with the inhibition of COX-2, TNFα, HIF1α, and VEGFA in the colon, suggest the potential of P. mahaleb water extract in contrasting the clinical symptoms related to ulcerative colitis. The inhibition of the hydrogen peroxide-induced DOPAC/DA ratio indicates promising neuroprotective effects. Finally, the downregulation of the gene expression of ACE2 and TMPRSS2 in H1299 cells, suggests the potential to inhibit SARS-CoV-2 virus entry in the human host. Overall, the results support the valorization of the local cultivation of P. mahaleb. 相似文献
9.
Fabio Ferrini Daniele Fraternale Sabrina Donati Zeppa Giancarlo Verardo Andrea Gorassini Vittoria Carrabs Maria Cristina Albertini Piero Sestili 《Molecules (Basel, Switzerland)》2021,26(16)
Cannabis sativa L. has been used for a long time to obtain food, fiber, and as a medicinal and psychoactive plant. Today, the nutraceutical potential of C. sativa is being increasingly reappraised; however, C. sativa roots remain poorly studied, despite citations in the scientific literature. In this direction, we identified and quantified the presence of valuable bioactives (namely, β-sitosterol, stigmasterol, campesterol, friedelin, and epi-friedelanol) in the root extracts of C. sativa, a finding which might pave the way to the exploitation of the therapeutic potential of all parts of the C. sativa plant. To facilitate root harvesting and processing, aeroponic (AP) and aeroponic-elicited cultures (AEP) were established and compared to soil-cultivated plants (SP). Interestingly, considerably increased plant growth—particularly of the roots—and a significant increase (up to 20-fold in the case of β-sitosterol) in the total content of the aforementioned roots’ bioactive molecules were observed in AP and AEP. In conclusion, aeroponics, an easy, standardized, contaminant-free cultivation technique, facilitates the harvesting/processing of roots along with a greater production of their secondary bioactive metabolites, which could be utilized in the formulation of health-promoting and health-care products. 相似文献
10.
Nicola Zerbinati Sabrina Sommatis Cristina Maccario Serena Di Francesco Maria Chiara Capillo Giulia Grimaldi Raffaele Rauso Martha Herrera Pier Luca Bencini Roberto Mocchi 《Molecules (Basel, Switzerland)》2021,26(24)
(1) Background: Cosmeceuticals are topical products applied to human skin to prevent skin ageing and maintain a healthy skin appearance. Their effectiveness is closely linked to the compounds present in a final formulation. In this article, we propose a panel of in vitro tests to support the efficacy assessment of an anti-ageing cream enriched with functional compounds. (2) Methods: biocompatibility and the irritant effect were evaluated on reconstructed human epidermis (RHE) and corneal epithelium (HCE) 3D models. After a preliminary MTT assay, normal human dermal fibroblasts (NHDF) and keratinocytes (HaCaT) were used to evaluate the extracellular matrix (ECM) protein synthesis, and interleukin-6 (IL-6) and metalloproteinase-1 (MMP-1) production. (3) Results: data collected showed good biocompatibility and demonstrated the absence of the irritant effect in both 3D models. Therefore, we demonstrated a statistical increase in collagen and elastin productions in NHDF cells. In HaCaT cells, we highlighted an anti-inflammatory effect through a reduction in IL-6 levels in inflammatory stimulated conditions. Moreover, the reduction of MMP-1 production after UV-B radiation was demonstrated, showing significant photo-protection. (4) Conclusion: a multiple in vitro assays approach is proposed for the valid and practical assessment of the anti-ageing protection, anti-inflammatory and biocompatible claims that can be assigned to a cosmetic product containing functional compounds. 相似文献