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Federico Zappaterra Stefania Costa Daniela Summa Valerio Bertolasi Bruno Semeraro Paola Pedrini Raissa Buzzi Silvia Vertuani 《Molecules (Basel, Switzerland)》2021,26(5)
Cortisone is a steroid widely used as an anti-inflammatory drug able to suppress the immune system, thus reducing inflammation and attendant pain and swelling at the site of an injury. Due to its numerous side effects, especially in prolonged and high-dose therapies, the development of the pharmaceutical industry is currently aimed at finding new compounds with similar activities but with minor or no side effects. Biotransformations are an important methodology towards more sustainable industrial processes, according to the principles of “green chemistry”. In this work, the biotransformation of cortisone with Rhodococcus rhodnii DSM 43960 to give two new steroids, i.e., 1,9β,17,21-tetrahydoxy-4-methyl-19-nor-9β-pregna-1,3,5(10)-trien-11,20-dione and 1,9β,17,20β,21-pentahydoxy-4-methyl-19-nor-9β-pregna-1,3,5(10)-trien-11-one, is reported. These new steroids have been fully characterized. 相似文献
375.
Andrew J. Warner James R. Lawson Valerio Fasano Michael J. Ingleson 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(38):11397-11401
BCl3 is an inexpensive electrophile which induces the borylative cyclization of a wide range of substituted alkynes to regioselectively form polycycles containing synthetically versatile C(sp2) boronate esters. It proceeds rapidly, with good yields and is compatible with a range of functional groups and substitution patterns. Intermolecular 1,2‐carboboration of alkynes is also achieved using BCl3 to generate trisubstituted vinyl boronate esters. 相似文献
376.
Hamdi Joda Valerio Beni Noora Alakulppi Jukka Partanen Kristina Lind Linda Strömbom Daniel Latta Julian Höth Ioanis Katakis Ciara K. O’Sullivan 《Analytical and bioanalytical chemistry》2014,406(12):2757-2769
Coeliac disease is a small intestinal disorder, induced by ingestion of gluten in genetically predisposed individuals. Coeliac disease has been strongly linked to human leukocyte antigens (HLA) located on chromosome 6, with almost 100 % of coeliac disease sufferers carrying either a HLA-DQ2 or HLA-DQ8 heterodimer, with the majority carrying HLA-DQ2 encoded by the DQA1*05:01/05:05, DQB1*02:01/02:02 alleles, whereas the remaining carry the HLA-DQ8 encoded by the DQA1*03:01, DQB1*03:02 alleles. In this work, we present the development of a multiplex electrochemical genosensor array of 36 electrodes, housed within a dedicated microfluidic platform and using a total of 10 sequence-specific probes for rapid medium-high resolution HLA-DQ2/DQ8 genotyping. An evaluation of the selectivity of the designed probes was carried out with the target sequences and 44 potentially interfering alleles, including single base mismatch differentiations; good selectivity was demonstrated. The performance of the electrochemical genosensor array was validated, analyzing real human samples for the presence of HLA-DQ2/DQ8 alleles, and compared with those obtained using laboratory-based HLA typing, and an excellent correlation was obtained. Figure
Electrode array and schematic of the proposed detection approach for the medium to high resolution electrochemical genotyping of alleles associated to Coeliac disease 相似文献
377.
Stefan Sulmann Dr. Daniele Dell'Orco Valerio Marino Dr. Petra Behnen Prof. Dr. Karl‐Wilhelm Koch 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(22):6756-6762
Fundamental components of signaling pathways are switch modes in key proteins that control start, duration, and ending of diverse signal transduction events. A large group of switch proteins are Ca2+ sensors, which undergo conformational changes in response to oscillating intracellular Ca2+ concentrations. Here we use dynamic light scattering and a recently developed approach based on surface plasmon resonance to compare the protein dynamics of a diverse set of prototypical Ca2+‐binding proteins including calmodulin, troponin C, recoverin, and guanylate cyclase‐activating protein. Surface plasmon resonance biosensor technology allows monitoring conformational changes under molecular crowding conditions, yielding for each Ca2+‐sensor protein a fingerprint profile that reflects different hydrodynamic properties under changing Ca2+ conditions and is extremely sensitive to even fine alterations induced by point mutations. We see, for example, a correlation between surface plasmon resonance, dynamic light scattering, and size‐exclusion chromatography data. Thus, changes in protein conformation correlate not only with the hydrodynamic size, but also with a rearrangement of the protein hydration shell and a change of the dielectric constant of water or of the protein–water interface. Our study provides insight into how rather small signaling proteins that have very similar three‐dimensional folding patterns differ in their Ca2+‐occupied functional state under crowding conditions. 相似文献
378.
Guido Crisponi Annalisa Dean Valerio Di Marco Joanna I. Lachowicz Valeria M. Nurchi Maurizio Remelli Andrea Tapparo 《Analytical and bioanalytical chemistry》2013,405(2-3):585-601
Our objective is to illustrate the activity of the groups operating in Italy involved in identification and study of new chelating agents, mainly intended for treatment of human pathology correlated with metal overload. The objective of “chelation therapy” is removal of toxic metal ions from the human body or attenuation of their toxicity by transforming them into less toxic compounds or by dislocating them from the site at which they exert a toxic action. Because most of this research activity is related to chelating agents for iron and aluminium, diseases related to these two metal ions are briefly treated. Iron overload is the most common metal toxicity disease worldwide. The toxicity of aluminium in dialysis patients was a serious problem for haemodialysis units in the seventies and eighties of the last century. In particular, this review focuses on research performed by the group at Cagliari and Ferrara, and by that at Padova. The former is studying, above all, bisphosphonate and kojic acid derivatives, and the latter is investigating 3,4-hydroxypyridinecarboxylic acids with differently substituted pyridinic rings. Figure
Aim of this paper is to illustrate the research on different classes of ligands, which are intended as possible chelating agents for the treatment of human pathologies correlated to iron and aluminium overload. 相似文献
379.
In this work we are investigating dopant environments in LiYF 4 -LiREF 4 (RE=rare-earth cations) solid solutions, via EXAFS. The main aims are to identify the local environmental symmetry and the average lattice distortion as a function of the concentration and the type of the RE ion. LiY 1 m x RE x F 4 (RE=Gd or Lu) (0< x <1) single crystals were grown by the Czochralski technique under argon or CF 4 atmosphere, crystal-pulling rates were 0.6-1 v mm/h for <100>-oriented boules, with 8-25 v rpm rotation rates. Most of the crystals were also codoped with 2.7 v mol% of neodymium in the melt. EXAFS measurements were performed in transmission and fluorescence modes in the synchrotron XAS line of the LNLS, Campinas, Brazil, in and above the L III absorption edges of the RE ions. The samples were prepared as powder films, for the transmission mode measurements, and as powder or single crystals for fluorescence mode measurements. The WINXAS program was used for data reduction and fitting, and the FEFF6 package was used for the simulations of the spectra. The EXAFS oscillation curves were obtained by standard procedure. 相似文献
380.
Abstract The computer modelling technique was used in the present work to study the intrinsic defects and the migration processes in KY3F10. The main intrinsic disorder was found to be F Frenkel pairs but at higher temperatures it is possible that KF pseudo-Schottky defects could also be present in the material. The ionic conduction process is mainly due to the fluorine ions migrating via both vacancy and interstitialcy mechanisms. 相似文献