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1.
The sodium-activated potassium channel Slack (KNa1.1, Slo2.2, or Kcnt1) is highly expressed in populations of sensory neurons, where it mediates the sodium-activated potassium current (IKNa) and modulates neuronal activity. Previous studies suggest that Slack is involved in the processing of neuropathic pain. However, mechanisms underlying the regulation of Slack activity in this context are poorly understood. Using whole-cell patch-clamp recordings we found that Slack-mediated IKNa in sensory neurons of mice is reduced after peripheral nerve injury, thereby contributing to neuropathic pain hypersensitivity. Interestingly, Slack is closely associated with ATP-sensitive P2X3 receptors in a population of sensory neurons. In vitro experiments revealed that Slack-mediated IKNa may be bidirectionally modulated in response to P2X3 activation. Moreover, mice lacking Slack show altered nocifensive responses to P2X3 stimulation. Our study identifies P2X3/Slack signaling as a mechanism contributing to hypersensitivity after peripheral nerve injury and proposes a potential novel strategy for treatment of neuropathic pain.  相似文献   
2.
In this paper, we report the design, synthesis and biological investigation of a series of peptidyl vinyl ketones obtained by modifying the P2 fragment of previously reported highly potent inhibitors of rhodesain, the main cysteine protease of Trypanosoma brucei rhodesiense. Investigation of the structure–activity relationship led us to identify new rhodesain inhibitors endowed with an improved selectivity profile (a selectivity index of up to 22 000 towards the target enzyme), and/or an improved antitrypanosomal activity in the sub-micromolar range.  相似文献   
3.
Radionuclide imaging of HER2 expression in tumours may enable stratification of patients with breast, ovarian, and gastroesophageal cancers for HER2-targeting therapies. A first-generation HER2-binding affibody molecule [99mTc]Tc-ZHER2:V2 demonstrated favorable imaging properties in preclinical studies. Thereafter, the affibody scaffold has been extensively modified, which increased its melting point, improved storage stability, and increased hydrophilicity of the surface. In this study, a second-generation affibody molecule (designated ZHER2:41071) with a new improved scaffold has been prepared and characterized. HER2-binding, biodistribution, and tumour-targeting properties of [99mTc]Tc-labelled ZHER2:41071 were investigated. These properties were compared with properties of the first-generation affibody molecules, [99mTc]Tc-ZHER2:V2 and [99mTc]Tc-ZHER2:2395. [99mTc]Tc-ZHER2:41071 bound specifically to HER2 expressing cells with an affinity of 58 ± 2 pM. The renal uptake for [99mTc]Tc-ZHER2:41071 and [99mTc]Tc-ZHER2:V2 was 25–30 fold lower when compared with [99mTc]Tc-ZHER2:2395. The uptake in tumour and kidney for [99mTc]Tc-ZHER2:41071 and [99mTc]Tc-ZHER2:V2 in SKOV-3 xenografts was similar. In conclusion, an extensive re-engineering of the scaffold did not compromise imaging properties of the affibody molecule labelled with 99mTc using a GGGC chelator. The new probe, [99mTc]Tc-ZHER2:41071 provided the best tumour-to-blood ratio compared to HER2-imaging probes for single photon emission computed tomography (SPECT) described in the literature so far. [99mTc]Tc-ZHER2:41071 is a promising candidate for further clinical translation studies.  相似文献   
4.
Medication packaging is essential to provide patients with guidance and correct use of their medicines for effective treatment. This research aims to increase knowledge about the medication packaging innovation process and its uptake towards patient‐centered packaging design. The study applied a qualitative research approach based on data from 25 in‐depth interviews with stakeholders involved in medication packaging design. The empirical data analysis revealed four themes that can improve and advance user‐centered packaging design: medication packaging innovation process, medication packaging functions and features, medication packaging design constraints, and patient‐centered medication packaging design. The findings suggest that medication packaging design is strongly affected by an emphasis on protective and safety packaging functions rather than on patients' needs. Packaging innovation usually is constrained by rigid incremental development processes, where compliance with regulations, extensive documentation, avoidance of manufacturing complexity, and considerations on cost prevail. These findings are discussed in relation to the three most evident trade‐offs for patient‐centered design: protection versus openability, utility versus cost, and complexity of manufacturability versus complexity of use. This research contributes with valuable input and additional evidence about the necessary shift to a user‐centered approach in a field that has not been design driven. This input complements previous research and provides an opportunity for industry decision makers and policy makers to lead patient‐centered packaging design that can benefit patients and relieve overloaded health care systems.  相似文献   
5.
There is growing interest in using photoinitiator-free systems in coating applications such as inkjet-printing, because residual photoinitiator can alter the properties of the resulting polymer. Bismaleimides (BMI) offer the opportunity to polymerize acrylates without the addition of photoinitiators, as this class of molecules can serve both as polymerizable monomer and as photoinitiator together with electron donor systems, like vinyl ether monomers or acrylates. The UV-induced copolymerization of a low-molecular-weight BMI with various acrylate monomers and oligomers without any photoinitiator was characterized. The BMI-acrylate systems show comparable polymerization speeds to widely used acrylic systems with photoinitiator. Superior thermal stability as well as thermomechanical properties are achieved by enhancing acrylics with BMI. Such photoinitiator-free systems lend themselves to be used for low-migration coatings as well as for high-temperature applications. Here, a characterization of selected BMI-acrylate mixtures regarding their photocuring kinetics and their application as inks for inkjet printing is shown. © 2019 The Authors. Journal of Applied Polymer Science published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47789.  相似文献   
6.
Accessing aldehydes from carboxylate moieties is often a challenging task. In this regard, carboxylate reductases (CARs) are promising catalysts provided by nature that are able to accomplish this task in just one step, avoiding over-reduction to the alcohol product. However, the heterologous expression of CARs can be quite difficult due to the excessive formation of insoluble protein, thus hindering further characterization and application of the enzyme. Here, the heterologous production of the carboxylate reductase from Nocardia otitidiscaviarum (NoCAR) was optimized by a combination of i) optimized cultivation conditions, ii) post-translational modification with a phosphopantetheinyl transferase and iii) selection of an appropriate expression strain. Especially, the selection of Escherichia coli tuner cells as host had a strong effect on the final 110-fold increase in the specific activity of NoCAR. This highly active NoCAR was used to reduce sodium benzoate to benzaldehyde, and it was successfully assembled with an in vitro regeneration of ATP and NADPH, being capable of reducing about 30 mM sodium benzoate with high selectivity in only 2 h of reaction.  相似文献   
7.
8.
The enzymatic conversion of lignins, possibly in combination with electrochemical oxidation, makes aromatics such as syringol, guaiacol, vanillin and catechol available in the qualities required by the fragrance industry. The lignins were obtained by soda digestion from wheat straw and Miscanthus, characterized and then converted with laccases. The overall yield amounted up to 9 wt % with a product spectrum confined to four substances. Catechol was the major product, with a fraction of ≈75 %. It can easily be isolated by extraction with acetone.  相似文献   
9.
The crystal structures of proton‐conducting BaZr1?xYxO3?x/2 (BZY05–BZY20) and BaCe0.8Y0.2O2.9 (BCY20) during hydration/dehydration has been studied by in situ high‐temperature X‐ray diffraction and thermal analysis. A contraction/expansion of the crystal lattice associated with dehydration/hydration was observed for all materials at elevated temperatures and the polymorphic phase transition temperatures of BaCe0.8Y0.2O2.9 were depressed by lowering the vapor pressure of water. A thermodynamic formalism is introduced to describe the chemical expansion associated with the hydration of oxygen vacancies in acceptor‐doped oxides. A conventional point defect model was applied to describe the lattice strain associated with the hydration. The chemical expansion is discussed with respect to the available volumetric data on the hydration of proton‐conducting oxide materials and its likely impact on ceramic fuel cells/hydrogen separation membranes utilizing a proton‐conducting electrolyte.  相似文献   
10.
PDZ (PSD‐95, Dlg, ZO‐1) domains are ubiquitous interaction modules that are involved in many cellular signal transduction pathways. Interference with PDZ‐mediated protein–protein interactions has important implications in disease‐related signaling processes. For this reason, PDZ domains have gained attention as potential targets for inhibitor design and, in the long run, drug development. Herein we report the development of small molecules to probe the function of the PDZ domain from human AF6 (ALL1‐fused gene from chromosome 6), which is an essential component of cell–cell junctions. These compounds bind to AF6 PDZ with substantially higher affinity than the peptide (Ile‐Gln‐Ser‐Val‐Glu‐Val) derived from its natural ligand, EphB2. In intact cells, the compounds inhibit the AF6–Bcr interaction and interfere with epidermal growth factor (EGF)‐dependent signaling.  相似文献   
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