Interaction of Masitinib with Organic Cation Transporters

Tyrosine kinase inhibitors (TKI) such as Masitinib were reported to be useful as therapeutic options in malignant disorders and nonmalignant diseases, like coronavirus disease 2019 (COVID-19). Most kinases must be translocated into targeted cells by the action of specific transport proteins, as they are hydrophilic and not able to cross cell membranes freely. Accordingly, the efficacy of TKI in target cells is closely dependent on the expression of their transporters. Specifically, Masitinib is an organic cation and is expected to interact with organic cation transporters (OCT and Multidrug and Toxin Extrusion proteins—MATE-). The aim of this work was to characterize the interaction of Masitinib with different OCTs. Human embryonic kidney 293 cells stably transfected with murine or human OCT were used for the experiments. The interaction of Masitinib with OCTs was investigated using quenching experiments. The intracellular accumulation of this drug was quantified using high performance liquid chromatography. Our results identified interactions of Masitinib with almost all investigated mouse (m) and human (h) OCTs and hMATE1 and indicated OCT1 and hOCT2 to be especially potent Masitinib translocators across cell membranes. Interestingly, some important differences were observed for the interaction with murine and human OCTs. In the future, investigations concerning further in vitro and in vivo properties of Masitinib and its efficacy related to transporter-related uptake mechanisms under pathophysiological conditions should be performed. Clinical trials in humans and other animals with Masitinib have already shown promising results. However, further research is necessary to understand the disease specific transport mechanisms of Masitinib to contribute to a successful and responsible therapy employment.     

Bioluminescence Production by Turnip Yellows Virus Infectious Clones: A New Way to Monitor Plant Virus Infection

We used the NanoLuc luciferase bioluminescent reporter system to detect turnip yellows virus (TuYV) in infected plants. For this, TuYV was genetically tagged by replacing the C-terminal part of the RT protein with full-length NanoLuc (TuYV-NL) or with the N-terminal domain of split NanoLuc (TuYV-N65-NL). Wild-type and recombinant viruses were agro-infiltrated in Nicotiana benthamiana, Montia perfoliata, and Arabidopsis thaliana. ELISA confirmed systemic infection and similar accumulation of the recombinant viruses in N. benthamiana and M. perfoliata but reduced systemic infection and lower accumulation in A. thaliana. RT-PCR analysis indicated that the recombinant sequences were stable in N. benthamiana and M. perfoliata but not in A. thaliana. Bioluminescence imaging detected TuYV-NL in inoculated and systemically infected leaves. For the detection of split NanoLuc, we constructed transgenic N. benthamiana plants expressing the C-terminal domain of split NanoLuc. Bioluminescence imaging of these plants after agro-infiltration with TuYV-N65-NL allowed the detection of the virus in systemically infected leaves. Taken together, our results show that NanoLuc luciferase can be used to monitor infection with TuYV.     

Diagnosing Czech Patients with Inherited Platelet Disorders

A single-center study was conducted on 120 patients with inherited disorders of primary hemostasis followed at our hematological center. These patients presented a variety of bleeding symptoms; however, they had no definitive diagnosis. Establishing a diagnosis has consequences for the investigation of probands in families and for treatment management; therefore, we aimed to improve the diagnosis rate in these patients by implementing advanced diagnostic methods. According to the accepted international guidelines at the time of study, we investigated platelet morphology, platelet function assay, light-transmission aggregometry, and flow cytometry. Using only these methods, we were unable to make a definitive diagnosis for most of our patients. However, next-generation sequencing (NGS), which was applied in 31 patients, allowed us to establish definitive diagnoses in six cases (variants in ANKRD26, ITGA2B, and F8) and helped us to identify suspected variants (NBEAL2, F2, BLOC1S6, AP3D1, GP1BB, ANO6, CD36, and ITGB3) and new suspected variants (GFI1B, FGA, GP1BA, and ITGA2B) in 11 patients. The role of NGS in patients with suspicious bleeding symptoms is growing and it changes the diagnostic algorithm. The greatest disadvantage of NGS, aside from the cost, is the occurrence of gene variants of uncertain significance.     

Sustained Increase in Serum Glial Fibrillary Acidic Protein after First ST-Elevation Myocardial Infarction

Acute ischemic cardiac injury predisposes one to cognitive impairment, dementia, and depression. Pathophysiologically, recent positron emission tomography data suggest astroglial activation after experimental myocardial infarction (MI). We analyzed peripheral surrogate markers of glial (and neuronal) damage serially within 12 months after the first ST-elevation MI (STEMI). Serum levels of glial fibrillary acidic protein (GFAP) and neurofilament light chain (NfL) were quantified using ultra-sensitive molecular immunoassays. Sufficient biomaterial was available from 45 STEMI patients (aged 28 to 78 years, median 56 years, 11% female). The median (quartiles) of GFAP was 63.8 (47.0, 89.9) pg/mL and of NfL 10.6 (7.2, 14.8) pg/mL at study entry 0–4 days after STEMI. GFAP after STEMI increased in the first 3 months, with a median change of +7.8 (0.4, 19.4) pg/mL (p = 0.007). It remained elevated without further relevant increases after 6 months (+11.7 (0.6, 23.5) pg/mL; p = 0.015), and 12 months (+10.3 (1.5, 22.7) pg/mL; p = 0.010) compared to the baseline. Larger relative infarction size was associated with a higher increase in GFAP (ρ = 0.41; p = 0.009). In contrast, NfL remained unaltered in the course of one year. Our findings support the idea of central nervous system involvement after MI, with GFAP as a potential peripheral biomarker of chronic glial damage as one pathophysiologic pathway.     

Effects of Sulforaphane-Induced Cell Death upon Repeated Passage of Either P-Glycoprotein-Negative or P-Glycoprotein-Positive L1210 Cell Variants

The expression of the membrane ABCB1 transporter in neoplastic cells is one of the most common causes of reduced sensitivity to chemotherapy. In our previous study, we investigated the effect of a single culture of ABCB1-negative (S) and ABCB1-positive variants of L1210 cells (R and T) in the presence of sulforaphane (SFN). We demonstrated that SFN induces the onset of autophagy more markedly in S cells than in R or T cells. In the current study, we focused on the effect of the repeated culture of S, R and T cells in SFN-containing media. The repeated cultures increased the onset of autophagy compared to the simple culture, mainly in S cells and to a lesser extent in R and T cells, as indicated by changes in the cellular content of 16 and 18 kDa fragments of LC3B protein or changes in the specific staining of cells with monodansylcadaverine. We conclude that SFN affects ABCB1-negative S cells more than ABCB1-positive R and T cells during repeated culturing. Changes in cell sensitivity to SFN appear to be related to the expression of genes for cell-cycle checkpoints, such as cyclins and cyclin-dependent kinases.     

Vitamin D as a Possible COVID-19 Prevention Strategy

Vitamin D is no longer considered an agent only affecting calcium phosphate metabolism. A number of studies over the past few years have demonstrated its role in immunomodulation and its influence on the development and functioning of the brain and nervous system. In the current epidemiological crisis caused by coronavirus disease 2019 (COVID-19), the immunoprotective role of vitamin D has been discussed by some authors regarding whether it contributes to protection against this serious disease or whether its use does not play a role. Non-standard approaches taken by laboratories in examining the serum levels of the vitamin D metabolite calcidiol have contributed to inconsistent results. We examined the serum of 60 volunteers in the spring and autumn of 2021 who declared whether they were taking vitamin D at the time of sampling. Furthermore, the tested participants noted whether they had experienced COVID-19. A newly developed liquid chromatography–tandem mass spectrometry (LC-MS/MS) method was used to measure calcidiol levels. The analysis of variance (ANOVA) model of Statgraphics Centurion 18 statistical software from Statgraphics Technologies was used for calculations. The results of this study showed that those who took vitamin D suffered significantly less often from COVID-19 than those who did not take vitamin D.     

Absolute characterization of high numerical aperture microscope objectives utilizing a dipole scatterer

Measuring the aberrations of optical systems is an essential step in the fabrication of high precision optical components. Such a characterization is usually ba...     

Optical Electron Spectroscopy and Electronic Properties for Multilayers ofal/Al203

Al/Al203 multilayers with nanometer scale are fabricated by thermal evaporation and natural oxidizationtechniques. The detection of X-ray and photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS) is performed, and the curve ofei (ki ) is got. The properties of the negative resistance for the multilayers are found.     

Energy-efficient operation of indirect adiabatic data center cooling systems via Newton-like phasor extremum seeking control

This paper considers the problem of optimizing the operation of Indirect Adiabatic Cooling (IAC) systems with application to data centers. Optimal operation is achieved when the required cooling demand is satisfied at the minimum energy cost. For this purpose, we design a supervisory control system, where the higher layer determines the optimal set-points for the local controllers by employing an Extremum Seeking Control (ESC) scheme. In particular, we consider a Newton-like phasor ESC, which augments the derivative estimator underlying the phasor approach to capture also the Hessian of the plant index and then it uses these estimates to steer the system along a Newton-like direction. The effectiveness of the considered approach is tested in simulation by exploiting a Matlab-based simulation environment including an IAC system and a computer room.