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21.
Synthetic prodiginine obatoclax shows promise as a potential anticancer drug. This compound promotes apoptosis of cancer cells, although the mechanism of action is unclear. To date, only the inhibition of BCL-2 proteins has been proposed as a mechanism of action. To gain insight into other possible modes of action, we have studied the anion-binding properties of obatoclax and related analogues in solution, in the solid state, and by means of density functional theory calculations. These compounds are well suited to interact with anions such as chloride and bicarbonate. The anion-transport properties of the compounds synthesized were assayed in model phospholipid liposomes by using a chloride-selective-electrode technique and (13)C NMR spectroscopy. The results demonstrated that these compounds are efficient anion exchangers that promote chloride, bicarbonate, and nitrate transport through lipid bilayers at very low concentrations. In vitro studies on small-cell lung carcinoma cell line GLC4 showed that active ionophores are able to discharge pH gradients in living cells and the cytotoxicity of these compounds correlates well with ionophoric activity.  相似文献   
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Interlaboratory comparisons are essential to bringing emerging technologies into biopharmaceutical industry practice and regulatory acceptance. As a result, an international team including 12 laboratories from 10 independent biopharmaceutical companies in the United States and Switzerland was formed to evaluate the precision and robustness of capillary isoelectric focusing (CIEF) to assess the charge heterogeneity of monoclonal antibodies. The different laboratories determined the apparent pI and the relative distribution of the charge isoforms of a representative monoclonal antibody (rMAb) sample using the same CIEF method. Statistical evaluation of the data was performed to determine within and between-laboratory consistencies and outlying information. The apparent pI data generated for each charge variant peak showed very good precision between laboratories with percentage of RSD values of ??0.5%. Similarly, the percentage of RSD for the rMAb charge variants percent peak area values are ??4.4% across different laboratories with different analysts using different lots of ampholytes and multiple instruments. Taken together, these results validate the appropriate use of CIEF in the biopharmaceutical industry in support of regulatory submissions.  相似文献   
23.
The electrochemical behaviour of Nodularin (NOD), a hepatotoxic cyclic pentapeptide, was studied at a glassy carbon electrode. NOD electrochemical oxidation is an irreversible, pH‐independent process, involving the transfer of one electron. Upon incubation in different pH electrolytes, chemical degradation of NOD was electrochemically detected by the appearance of a new oxidation peak. The chemically degraded NOD (cdNOD), undergoes an irreversible, pH‐dependent oxidation, and its redox products are reversibly oxidised. The charge transfer properties of cdNOD as well as of its redox metabolites were investigated. Mechanisms for NOD oxidation, NOD chemical degradation and oxidation of cdNOD and its metabolites were proposed.  相似文献   
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Journal of Thermal Analysis and Calorimetry - Acid–base multicomponent systems based on active pharmaceutical ingredients 2-chloro-5-nitrobenzoic acid (2Cl5NBH) and monoethanolamine were...  相似文献   
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The interaction between the single hexarepeat unit of chicken prion protein [ChPrP(54-59)] and Cu(II) was investigated by NMR, finding different coordination modes for the trans/trans and cis/trans isomers.  相似文献   
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Metal-organic cages (MOCs) are popular host architectures assembled from ligands and metal ions/nodes. Assembling structurally complex, low-symmetry MOCs with anisotropic cavities can be limited by the formation of statistical isomer libraries. We set out to investigate the use of primary coordination-sphere engineering (CSE) to bias isomer selectivity within homo- and heteroleptic PdnL2n cages. Unexpected differences in selectivities between alternative donor groups led us to recognise the significant impact of the second coordination sphere on isomer stabilities. From this, molecular-level insight into the origins of selectivity between cis and trans diastereoisomers was gained, highlighting the importance of both host–guest and host-solvent interactions, in addition to ligand design. This detailed understanding allows precision engineering of low-symmetry MOC assemblies without wholesale redesign of the ligand framework, and fundamentally provides a theoretical scaffold for the development of stimuli-responsive, shape-shifting MOCs.  相似文献   
29.
The accumulation of amyloid plaques, or misfolded fragments of proteins, leads to the development of a condition known as amyloidosis, which is clinically recognized as a systemic disease. Amyloidosis plays a special role in the pathogenesis of neurodegenerative diseases such as Alzheimer’s disease (AD), Parkinson’s disease, and rheumatoid arthritis (RA). The occurrence of amyloidosis correlates with the aging process of the organism, and since nowadays, old age is determined by the comfort of functioning and the elimination of unpleasant disease symptoms in the elderly, exposure to this subject is justified. In Alzheimer’s disease, amyloid plaques negatively affect glutaminergic and cholinergic transmission and loss of sympathetic protein, while in RA, amyloids stimulated by the activity of the immune system affect the degradation of the osteoarticular bond. The following monograph draws attention to the over-reactivity of the immune system in AD and RA, describes the functionality of the blood–brain barrier as an intermediary medium between RA and AD, and indicates the direction of research to date, focusing on determining the relationship and the cause–effect link between these disorders. The paper presents possible directions for the treatment of amyloidosis, with particular emphasis on innovative therapies.  相似文献   
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S. A. Koldobskiy  O. Adriani  G. A. Bazilevskaya  G. C. Barbarino  R. Bellotti  E. A. Bogomolov  M. Boezio  V. Bonvicini  M. Bongi  S. Bottai  A. Bruno  A. Vacchi  E. Vannuccini  G. I. Vasilyev  S. A. Voronov  A. M. Galper  C. De Santis  V. Di Felice  G. Zampa  N. Zampa  M. Casolino  D. Campana  A. V. Karelin  P. Carlson  G. Castellini  F. Cafagna  A. A. Kvashnin  A. N. Kvashnin  S. V. Koldashov  S. Y. Krutkov  A. A. Leonov  A. G. Mayorov  V. V. Malakhov  M. Martucci  L. Marcelli  W. Menn  M. Merge  V. V. Mikhailov  E. Mocchiutti  A. Monaco  N. Mori  R. Munini  G. Osteria  B. Panico  P. Papini  P. Picozza  M. Pearce  M. Ricci  S. B. Ricciarini  M. F. Runtso  M. Simon  R. Sparvoli  P. Spillantini  Y. I. Stozhkov  Y. T. Yurkin 《Bulletin of the Russian Academy of Sciences: Physics》2017,81(2):151-153
The preliminary results from measurements of deuteron fluxes in galactic cosmic rays (GCR) in the vicinity of the Earth in 2006–2009 are presented. The results are obtained by analyzing data from the PAMELA experiment aboard the Resurs DK-1 satellite. High-precision detection instruments provided an opportunity to identify GCR deuterons and measure their spectrum in the energy interval of 90–650MeV/nucleon. Spectra averaged over six-month intervals from the summer of 2006 to the summer of 2009 (the solar activity minimum) are presented. The influence of solar modulation on the observed spectrum is clearly seen in the results.  相似文献   
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