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81.
Kristel Kegler Ilka Imbschweiler Reiner Ulrich Peter Kovermann Christoph Fahlke Ulrich Deschl Arno Kalkuhl Wolfgang Baumgärnter Konstantin Wewetzer 《Journal of neural transmission (Vienna, Austria : 1996)》2014,121(6):569-581
Central nervous system (CNS) injury triggers production of myelinating Schwann cells from endogenous oligodendrocyte precursors (OLPs). These CNS Schwann cells may be attractive candidates for novel therapeutic strategies aiming to promote endogenous CNS repair. However, CNS Schwann cells have been so far mainly characterized in situ regarding morphology and marker expression, and it has remained enigmatic whether they display functional properties distinct from peripheral nervous system (PNS) Schwann cells. Potassium channels (K+) have been implicated in progenitor and glial cell proliferation after injury and may, therefore, represent a suitable pharmacological target. In the present study, we focused on the function and expression of voltage-gated K+ channels Kv1–12 and accessory β-subunits in purified adult canine CNS and PNS Schwann cell cultures using electrophysiology and microarray analysis and characterized their antigenic phenotype. We show here that K+ channels differed significantly in both cell types. While CNS Schwann cells displayed prominent K D-mediated K+ currents, PNS Schwann cells elicited K D- and KA-type K+ currents. Inhibition of K+ currents by TEA and Ba2+ was more effective in CNS Schwann cells. These functional differences were not paralleled by differential mRNA expression of Kv1–12 and accessory β-subunits. However, O4/A2B5 and GFAP expressions were significantly higher and lower, respectively, in CNS than in PNS Schwann cells. Taken together, this is the first evidence that CNS Schwann cells display specific properties not shared by their peripheral counterpart. Both Kv currents and increased O4/A2B5 expression were reminiscent of OLPs suggesting that CNS Schwann cells retain OLP features during maturation. 相似文献
82.
Sergey V. Cheresiz Andrey D. Volgin Alexandra Kokorina Evsyukova Alim A.O. Bashirzade Konstantin A. Demin 《Journal of neurogenetics》2020,34(2):203-215
AbstractDue to its fully sequenced genome, high genetic homology to humans, external fertilization, fast development, transparency of embryos, low cost and active reproduction, the zebrafish (Danio rerio) has become a novel promising model organism in biomedicine. Zebrafish are a useful tool in genetic and neuroscience research, including linking various genetic mutations to brain mechanisms using forward and reverse genetics. These approaches have produced novel models of rare genetic CNS disorders and common brain illnesses, such as addiction, aggression, anxiety and depression. Genetically modified zebrafish also foster neuroanatomical studies, manipulating neural circuits and linking them to different behaviors. Here, we discuss recent advances in neurogenetics of zebrafish, and evaluate their unique strengths, inherent limitations and the rapidly growing potential for elucidating the conserved roles of genes in neuropsychiatric disorders. 相似文献
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85.
Natalia L. Varich Galina K. Sadykova Alexei G. Prilipov Konstantin S. Kochergin-Nikitsky Robert G. Webster Nikolai V. Kaverin 《Archives of virology》2014,159(6):1493-1497
Amino acid positions recognized by monoclonal antibodies (MAbs) in the influenza A virus nucleoprotein (NP) have been reported. As these residues were scattered in the three-dimensional (3D) structure of NP, no patterns of the architecture of antibody-binding sites could be inferred. Here, we used site-specific mutagenesis and ELISA to screen the amino acids surrounding position 470 recognized by the MAb 3/1 as a linear epitope. Ten amino acid residues involved in the reaction of NP with the MAb 3/1 and the MAb 469/6 were identified. Our data are the first to outline a compact site recognized by MAbs in the 3D structure of the influenza virus NP. 相似文献
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87.
Konstantin Andryushin Svetlana Dudkina Sushrisangita Sahoo Lidiya Shilkina Vladimir Alyoshin Ekaterina Triger Inna Andryushina Iliya Verbenko Daniil Rudskiy Angela Rudskaya Larisa Reznichenko 《Materials》2022,15(6)
Ferro-piezoceramic materials (FPCM) with different degrees of ferrohardness were fabricated by double solid-phase synthesis followed by the sintering technique using hot pressing method. The X-ray studies carried out in a wide temperature range showed that with increasing temperature, each of the studied FPCM undergoes a series of phase transformations, accompanied by a change in the symmetry of the unit cell. In this case, near the phase transition to the nonpolar cubic phase, in each of the FPCM, the formation of a fuzzy symmetry region is observed, which is characterized by weak distortions and temperature–time instability of the crystal structure. The study of the piezoelectric modulus d33 in the quasi-static regime as a function of temperature made it possible to reveal the different nature of its behavior in materials of various degrees of ferrohardness. It was shown that the conservation of the state in ferrosoft materials above the Curie temperature is associated with the relaxation nature of the change in their properties, the existence of a region of fuzzy symmetry (noncubic phase) in them above the Curie temperature, and increased inertia of the system. The expediency of taking into account the presented results in the development of electromechanical converters based on FPCM of various degrees of ferrohardness, operated under temperature effects, including cyclic ones, was shown. 相似文献
88.
BACKGROUND: In order to successfully perform aggressive cytoreductive surgery for patients with recurrent epithelial ovarian cancer, resection of retroperitoneal disease in close proximity to major vessels is often required. CASE: We describe a case of a 44-year-old female patient with a history of Stage IV carcinoma of the ovary, who underwent a successful secondary debulking procedure. To remove the left para-aortic tumor implant she required complete mobilization of the left kidney, with skeletonization of the left renal artery and vein. Postoperatively, the patient developed left renal artery thrombosis necessitating a unilateral nephrectomy. CONCLUSION: This is, to our knowledge, the first reported case of renal artery thrombosis following a debulking procedure. Gynecologic oncologists should be aware of this possibility and be familiar with the diagnosis and management of this condition. 相似文献
89.
Marine E. Bozdaganyan Konstantin V. Shaitan Mikhail P. Kirpichnikov Olga S. Sokolova Philipp S. Orekhov 《Viruses》2022,14(2)
Currently, SARS-CoV-2 causing coronavirus disease 2019 (COVID-19) is responsible for one of the most deleterious pandemics of our time. The interaction between the ACE2 receptors at the surface of human cells and the viral Spike (S) protein triggers the infection, making the receptor-binding domain (RBD) of the SARS-CoV-2 S-protein a focal target for the neutralizing antibodies (Abs). Despite the recent progress in the development and deployment of vaccines, the emergence of novel variants of SARS-CoV-2 insensitive to Abs produced in response to the vaccine administration and/or monoclonal ones represent a potential danger. Here, we analyzed the diversity of neutralizing Ab epitopes and assessed the possible effects of single and multiple mutations in the RBD of SARS-CoV-2 S-protein on its binding affinity to various antibodies and the human ACE2 receptor using bioinformatics approaches. The RBD-Ab complexes with experimentally resolved structures were grouped into four clusters with distinct features at sequence and structure level. The performed computational analysis indicates that while single amino acid replacements in RBD may only cause partial impairment of the Abs binding, moreover, limited to specific epitopes, the variants of SARS-CoV-2 with multiple mutations, including some which were already detected in the population, may potentially result in a much broader antigenic escape. Further analysis of the existing RBD variants pointed to the trade-off between ACE2 binding and antigenic escape as a key limiting factor for the emergence of novel SAR-CoV-2 strains, as the naturally occurring mutations in RBD tend to reduce its binding affinity to Abs but not to ACE2. The results provide guidelines for further experimental studies aiming to identify high-risk RBD mutations that allow for an antigenic escape. 相似文献
90.
Teresa Thim Konstantin Johannes Scholz Karl-Anton Hiller Wolfgang Buchalla Christian Kirschneck Jonathan Fleiner Johan Peter Woelber Fabian Cieplik 《Nutrients》2022,14(4)
The influence of patient-specific factors such as medical conditions, low-density lipoprotein cholesterol (LDL-C) or levels of 25-hydroxyvitamin D (25OHD) on periodontal diseases is frequently discussed in the literature. Therefore, the aim of this retrospective cross-sectional study was to evaluate potential associations between radiographic bone loss (RBL) and patient-specific risk factors, particularly LDL-C and 25OHD levels. Patients from a dental practice, who received full-mouth cone beam CTs (CBCTs) and blood-sampling in the course of implant treatment planning, were included in this study. RBL was determined at six sites per tooth from CBCT data. LDL-C and 25OHD levels were measured from venous blood samples. Other patient-specific risk factors were assessed based on anamnesis and dental charts. Statistical analysis was performed applying non-parametric procedures (Mann–Whitney U tests, error rates method). Data from 163 patients could be included in the analysis. RBL was significantly higher in male patients, older age groups, smokers, patients with high DMFT (decayed/missing/filled teeth) score, lower number of teeth, and high LDL-C levels (≥160 mg/dL). Furthermore, patients with high 25OHD levels (≥40 ng/mL) exhibited significantly less RBL. In summary, RBL was found to be associated with known patient-specific markers, particularly with age and high LDL-C levels. 相似文献