Расчет параметров гидротранспорта высококонцентрированных гидросмесей в условиях предприятий Кривбасса

Для технології складування на підприємствах Кривбасу відходів збагачення, згущених до концентрації пасти, запропоновано методики розрахунків параметрів та режимів роботи/ гідротранспортних установок з урахуванням гідравлічних та реологічних характеристик.The methods of calculation of parameters and regimes of hydrotransport plants operation for technology of stocking of cleaning rejects condensed till paste concentration at Krivbas enterprises taking into account hydraulic and rheological characteristics are offered

Role of acetylcholine and polyspecific cation transporters in serotonin-induced bronchoconstriction in the mouse

BACKGROUND: It has been proposed that serotonin (5-HT)-mediated constriction of the murine trachea is largely dependent on acetylcholine (ACh) released from the epithelium. We recently demonstrated that ACh can be released from non-neuronal cells by corticosteroid-sensitive polyspecific organic cation transporters (OCTs), which are also expressed by airway epithelial cells. Hence, the hypothesis emerged that 5-HT evokes bronchoconstriction by inducing release of ACh from epithelial cells via OCTs. METHODS: We tested this hypothesis by analysing bronchoconstriction in precision-cut murine lung slices using OCT and muscarinic ACh receptor knockout mouse strains. Epithelial ACh content was measured by HPLC, and the tissue distribution of OCT isoforms was determined by immunohistochemistry. RESULTS: Epithelial ACh content was significantly higher in OCT1/2 double-knockout mice (42 ± 10 % of the content of the epithelium-denuded trachea, n = 9) than in wild-type mice (16.8 ± 3.6 %, n = 11). In wild-type mice, 5-HT (1 μM) caused a bronchoconstriction that slightly exceeded that evoked by muscarine (1 μM) in intact bronchi but amounted to only 66% of the response to muscarine after epithelium removal. 5-HT-induced bronchoconstriction was undiminished in M(2)/M(3 )muscarinic ACh receptor double-knockout mice which were entirely unresponsive to muscarine. Corticosterone (1 μM) significantly reduced 5-HT-induced bronchoconstriction in wild-type and OCT1/2 double-knockout mice, but not in OCT3 knockout mice. This effect persisted after removal of the bronchial epithelium. Immunohistochemistry localized OCT3 to the bronchial smooth muscle. CONCLUSION: The doubling of airway epithelial ACh content in OCT1/2(-/- )mice is consistent with the concept that OCT1 and/or 2 mediate ACh release from the respiratory epithelium. This effect, however, does not contribute to 5-HT-induced constriction of murine intrapulmonary bronchi. Instead, this activity involves 1) a non-cholinergic epithelium-dependent component, and 2) direct stimulation of bronchial smooth muscle cells, a response which is partly sensitive to acutely administered corticosterone acting on OCT3. These data provide new insights into the mechanisms involved in 5-HT-induced bronchoconstriction, including novel information about non-genomic, acute effects of corticosteroids on bronchoconstriction

Bioanalytical assay for the quantification of the tyrosine kinase inhibitor EAI045 and its major metabolite PIA in mouse plasma and tissue homogenates using liquid chromatography–tandem mass spectrometry

EAI045 is a tyrosine kinase inhibitor (TKI) that targets the mutant epidermal growth factor receptor (EGFR). It was developed to control resistance to available EGFR TKIs. In this study, a major metabolite of EAI045, (5-fluoro-2-hydroxyphenyl)(1-oxo-1,3-dihydro-2H-isoindol-2-yl)acetic acid (PIA), was discovered as a hydrolysis product of the parent drug. A validated assay for both analytes in mouse plasma and tissue homogenates from brain, kidney, liver, lung, spleen, and small intestine with content was set up using LC–MS/MS. Samples were prepared by protein precipitation with acetonitrile and with PLX4720 as internal standard. Separation was performed on a bridged ethylene hybrid C18 column by gradient elution with 0.1% v/v formic acid and methanol. Using positive electrospray, detection was performed in selected reaction monitoring mode. A linear calibration range of 2–2,000 ng/ml was used and validated for both analytes. Precision values ranged between 2.0 and 7.5% for EAI045 and between 2.2 and 12.1% for the metabolite, and accuracy values were between 91.1 and 107.6% for EAI045 and between 87.6 and 100.6% for the metabolite. Both analytes were sufficiently stable under the relevant analytical conditions. Finally, the assay was applied to analyze mouse plasma and tissue levels in a pharmacokinetic study in FVB/NRj wild-type female mice treated with oral EAI045

P-Glycoprotein in skin contributes to transdermal absorption of topical corticosteroids

ATP binding cassette transporters, P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP), are expressed in skin, but their involvement in transdermal absorption of clinically used drugs remains unknown. Here, we examined their role in transdermal absorption of corticosteroids. Skin and plasma concentrations of dexamethasone after dermal application were reduced in P-gp and BCRP triple-knockout (Mdr1a/1b/Bcrp−/−) mice. The skin concentration in Mdr1a/1b/Bcrp−/− mice was reduced in the dermis, but not in the epidermis, indicating that functional expression of these transporters in skin is compartmentalized. Involvement of these transporters in dermal transport of dexamethasone was also supported by the observation of a higher epidermal concentration in Mdr1a/1b/Bcrp−/− than wild-type mice during intravenous infusion. Transdermal absorption after dermal application of prednisolone, but not methylprednisolone or ethinyl estradiol, was also lower in Mdr1a/1b/Bcrp−/− than in wild-type mice. Transport studies in epithelial cell lines transfected with P-gp or BCRP showed that dexamethasone and prednisolone are substrates of P-gp, but are minimally transported by BCRP. Thus, our findings suggest that P-gp is involved in transdermal absorption of at least some corticosteroids in vivo. P-gp might be available as a target for inhibition in order to deliver topically applied drugs and cosmetics in a manner that minimizes systemic exposure. © 2017 Elsevier B.V.Embargo Period 12 month

Development and validation of an HPLC-MS/MS method to quantify the KRAS inhibitor adagrasib in mouse plasma and tissue-related matrices

We developed and validated an assay utilizing a liquid chromatography-tandem mass spectrometry technique to quantify the KRAS inhibitor adagrasib in mouse plasma and seven tissue-related matrices. The straightforward protein precipitation technique was selected to extract adagrasib and the internal standard salinomycin from the matrices. Gradient elution of acetonitrile and water modified with 0.5% (v/v) ammonium hydroxide and 0.02% (v/v) acetic acid on a C 18 column at a flow rate of 0.6 ml/min was applied to separate the analytes. Both adagrasib and salinomycin were detected with a triple quadrupole mass spectrometer with positive electrospray ionization in a selected reaction monitoring mode. A linear calibration range of 2-2,000 ng/ml of adagrasib was demonstrated during the validation. In addition, the reported precision values (intra- and inter-day) were between 3.5 and 14.9%, while the accuracy values were 85.5-111.0% for all tested levels in all investigated matrices. Adagrasib in mouse plasma was reported to have good stability at room temperature, while adagrasib in tissue-related matrices was stable on ice for up to 4 h (matrix dependent). Finally, this method was successfully applied to determine the pharmacokinetic profile and tissue distribution of adagrasib in wild-type mice

Місце Редакційних комісій у підготовці проекту Селянської реформи 19 лютого 1861 р.

В статті проаналізовано структуру Редакційних комісій та процес розробки ними правової бази для проведення Селянської реформи 1861 р.В статье рассматривается структура Редакционных комиссий и процесс разработки ими правовой базы для проведения Крестьянской реформы 1861 г.In article to the analyze structure Redactions committee and legal regulations proceedings cultivate to be realization peasant reform 1861 year

Validated LC-MS/MS method for simultaneous quantification of KRASG12C inhibitor sotorasib and its major circulating metabolite (M24) in mouse matrices and its application in a mouse pharmacokinetic study.

We have successfully developed and validated a bioanalytical assay using liquid chromatography tandem mass spectrometry to simultaneously quantify the first approved KRAS G12C inhibitor sotorasib and its major circulating metabolite (M24) in various mouse matrices. M24 was synthesized in-house via low-pH hydrolysis. We utilized a fast and efficient protein precipitation method in a 96-well plate format to extract both analytes from biological matrices. Erlotinib was selected as the internal standard in this assay. Gradient elution using methanol and 0.1 % formic acid in water (v/v) was applied on an Acquity UPLC BEH C18 column to separate all analytes. Sotorasib, M24, and erlotinib were detected with a triple quadrupole mass spectrometer in positive electrospray ionization in multiple reaction monitoring mode. During the validation and sample quantification, a linear calibration range was observed for both sotorasib and M24 in a range of 4 - 4000 nM and 1 - 1000 nM, respectively. The %bias and %CV (both intra- and inter-day) for all tested levels in all investigated matrices were lower than 15 % as required by the guidelines. Sotorasib had a rather short room temperature stability in mouse plasma for up to 8 h compared to M24 which was stable up to 16 h at room temperature. This method has been successfully applied to measure sotorasib and M24 in several mouse matrices from three different mouse strains. We can conclude that the plasma exposure of sotorasib in mice is limited via human CYP3A4- and mouse Cyp3a-mediated metabolism of sotorasib into M24