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protein precipitation method for the determination of oxcarbazepine and its major active metabolite 10-monohydroxy derivative in human plasma by liquid chromatography tandem mass spectrometry was established. analytes were extracted from human plasma samples by protein precipitation with acetonitrile. analyte separation was done using phenomenex Kinetex™ Biphenyl (2.6 µm, 100 x 2.1 mm) column using isocratic elution with a mobile phase of 5 mM ammonium bicarbonate (42.5%) and methanol (57.5%) at a flow rate of 0.3 mL/min and an injection volume of 5 µL. The detection was performed on a triple quadrupole mass spectrometer by multiple reaction monitoring mode to monitor the precursor-to-product ion transitions of m/z 253.1 → 180.0, 257.2 → 184.1 for oxcarbazepine and oxcarbazepine-D4, and 255.1 → 194.2, 259.2 → 198.2 for 10-monohydroxy derivative and 10,11-Dihydro-10-hydroxy carbamazepine-D4 in positive electrospray ionization mode, correspondingly. The method was validated over a concentration range of 20-8000 ng/mL for oxcarbazepine and 37.5-15000 ng/mL for 10-monohydroxy derivative on SCIeX Triple Quad 4500 MS System. Total run time was 4 min. Sample preparation was conducted in ice water bath because of instability of oxcarbazepine in plasma at room temperature. The method was validated in accordance with U.S Food and Drug administration and european Medicines agency guidelines. Method validation has been proved by a variety of tests for matrix effects, extraction efficiency, selectivity, linearity, sensitivity, precision, recovery and stability and can be successfully applied for the bioequivalence/pharmacokinetic studies of oxcarbazepine and its 10-monohydroxy derivative. This method has been designed for bioequivalence study for formulations containing 600 mg of oxcarbazepine. [ABSTRACT FROM AUTHOR]

In order to survive and evolve the humanity needs changes and transformation. Changes in education are of particular importance because education plays a crucial role in creating a sustainable future. Today, we are undergoing digital transformation in all areas of our life, but educational institutions are only taking the first steps to become digital. Digital transformation of education should involve not only using computers at classes but designing new methods of teaching and learning as well. Technologies should benefit education. The purpose of this work is to share the successful experience of educators of the English for engineering technologies department at Bauman University in designing a new multimedia two-year English course for undergraduates at technical universities. The course “English in the Digital Age” includes a Student’s Book in the digital format with integrated audio and video authentic materials, a Workbook with the key and mock tests, a Teacher’s Resource Book with detailed teaching notes and an online course for English grammar drilling with an answer reveal function and personalized testing with automatic assessment. The course essential feature is that an online self-study grammar course and face-to-face learning process are successfully combined and personalized. The benefit of the work is the best practice in creating a basis for digital transformation of learning and teaching English at a technical university.

Ataxia-telangiectasia mutated (ATM) gene mediates acute phase DNA damage repair pathways. Inhibition of ATM is theorized to amplify the effects of radiotherapy (RT). AZD1390 is a first-in-class, investigational ATM inhibitor. We conducted a combined phase 0/1b study to evaluate AZD1390 pharmacokinetics (PK) and pharmacodynamics (PD) in patients with newly-diagnosed glioblastoma (GBM), graduating patients to a phase 1b study evaluating a therapeutic regimen of AZD1390 with concurrent RT in O6-methylguanine methyltransferase (MGMT) unmethylated tumors exceeding a prespecified PK threshold in non-enhancing tumor. Patients with presumed newly-diagnosed GBM were enrolled in a phase 0 study receiving 3 days of AZD1390 prior to planned resection 4-6 or 23-25 hours following the final dose. Tumor tissue, cerebrospinal fluid (CSF), and plasma were collected. Total and unbound drug concentrations were measured using validated LC-MS/MS methods. ATM inhibition was assessed by quantification of pRAD50 after 5 Gy ex vivo irradiation in surgical tissue compared to non-irradiated control tissue. A PK 'trigger', 2nM unbound drug levels in Gd-non-enhancing tumor, determined eligibility for the therapeutic phase 1b expansion portion of the study. Patients with MGMT-unmethylated tumors exceeding this PK threshold were eligible for expansion phase dosing of AZD1390 with concurrent RT, 60 Gy in 30 fractions using volumetric-modulated arc therapy (VMAT). Patients with MGMT methylated tumors were not eligible for the expansion phase and proceeded with temozolomide (TMZ) plus RT followed by maintenance TMZ. Seventeen patients were enrolled onto the phase 0 portion of the study. Three patients were excluded from the PK analysis due to dosing deviation (n = 1) or non-GBM diagnosis (n = 2). For the 14 patients included in the PK analysis, the mean unbound concentration of AZD1390 in Gd-non-enhancing tumor was 12.4 and 4.4 pmol/g, for the 4-6 hours preop (n = 10), and 23-25 hours preop (n = 4) time cohorts, respectively. The suppression of pRAD50 levels after ex vivo RT was observed in AZD1390- treated patients (median 0.2% for 4-6-hours cohorts and 1.9% for 23-25 hours cohort vs 32.3% for control cohort). One non-serious adverse event of grade 3 hyperammonemia was reported and deemed potentially related to AZD1390. No serious adverse events related to AZD1390 were reported. As of November 2023, 3 patients with MGMT-unmethylated tumors have completed therapeutic dosing of AZD1390 with concurrent radiotherapy with a median clinical follow-up of 2.3 months. AZD1390 achieved pharmacologically-relevant concentrations in non-enhancing, newly- diagnosed GBM tissue and effectively inhibits ATM as measured by suppression of radiation-induced pRAD50 increases. AZD1390 with concurrent RT is well-tolerated with initial follow-up. Updated follow-up will better determine long-term safety and efficacy of this first-in-class combination. [ABSTRACT FROM AUTHOR]

Mutational signature analysis gained significant attention for providing critical insights into the underlying mutational processes for various DNA single base substitution (SBS) signatures and their associations with different cancer types. Recently, RNA single base substitution (RNA-SBS) signatures were defined and described by decomposing RNA variants found in non-small cell lung cancer. Through statistical association, they attributed Apolipoprotein B mRNA Editing Enzyme, Catalytic Polypeptide 3A (APOBEC3A) mutagenesis to the RNA-SBS2 signature. Here, we provide the first validation of an RNA-SBS mutational signature by decomposing novel exogenous and endogenous APOBEC3A RNA editing signatures into COSMICv3.4 RNA-SBS reference signatures. Additionally, we have identified novel RNA-SBS signatures for APOBEC1, APOBEC3B, and APOBEC3G., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Niraparib is a potent and orally bioavailable inhibitor of poly (ADP-ribose) polymerase (PARP) with high specificity for isoforms 1 and 2. It has been approved by the U.S. Food and Drug Administration for ovarian cancer maintenance therapy and is currently under development for various cancers, including glioblastoma. To assess central nervous system (CNS) penetration of niraparib in glioblastoma patients, a novel bioanalytical method was developed to measure total and unbound niraparib levels in human brain tumor tissue and cerebrospinal fluid (CSF). The method was validated using plasma as a surrogate matrix over the concentration range of 1-10,000 nM on an LC-MS/MS system. The MS/MS detection was conducted in positive electrospray ionization mode, while chromatography was performed using a Kinetex™ PS C18 column with a total 3.5-minute gradient elution run time. The maximum coefficient of variation for both intra- and inter-day precision was 10.6%, with accuracy ranging from 92.8% - 118.5% across all matrices. Niraparib was stable in human brain homogenate for at least 6 hours at room temperature (RT) and 32 days at -20°C, as well as in stock and working solutions for at least 21 hours (RT) and 278 days (4°C). Equilibrium dialysis experiments revealed the fractions unbound of 0.05 and 0.16 for niraparib in human brain and plasma, respectively. The validated method is currently employed to assess niraparib levels in human glioblastoma tissue, CSF, and plasma in an ongoing trial on newly diagnosed glioblastoma and recurrent IDH1/2(+) ATRX mutant glioma patients (NCT05076513). Initial results of calculated total (K p ) and unbound (K p,uu ) tumor-to-plasma partition coefficients indicate significant brain penetration ability of niraparib in glioblastoma patients., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing financial interests or personal relationships which could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

The 1st Global Summit on War and Cancer (GSWC) united leaders, medical professionals, policymakers, and advocates to address cancer issues in conflict zones featuring speakers from around 50 countries.

Histone deacetylase (HDAC) inhibitors have garnered considerable interest for the treatment of adult and pediatric malignant brain tumors. However, owing to their broad-spectrum nature and inability to effectively penetrate the blood-brain barrier, HDAC inhibitors have failed to provide substantial clinical benefit to patients with glioblastoma (GBM) to date. Moreover, global inhibition of HDACs results in widespread toxicity, highlighting the need for selective isoform targeting. Although no isoform-specific HDAC inhibitors are currently available, the second-generation hydroxamic acid-based HDAC inhibitor quisinostat possesses subnanomolar specificity for class I HDAC isoforms, particularly HDAC1 and HDAC2. It has been shown that HDAC1 is the essential HDAC in GBM. This study analyzed the neuropharmacokinetic, pharmacodynamic, and radiation-sensitizing properties of quisinostat in preclinical models of GBM. It was found that quisinostat is a well-tolerated and brain-penetrant molecule that extended survival when administered in combination with radiation in vivo. The pharmacokinetic-pharmacodynamic-efficacy relationship was established by correlating free drug concentrations and evidence of target modulation in the brain with survival benefit. Together, these data provide a strong rationale for clinical development of quisinostat as a radiosensitizer for the treatment of GBM.

Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder and warrants further study as well as timely treatment. Additionally, the mechanisms of the brain's intrinsic defense against chronic injury are not yet fully understood. Herein, we examined the response of the main neurogenic niches to amyloid exposure and the associated changes in structure and synaptic activity. Flow cytometry of Nestin-, Vimentin-, Nestin/Vimentin-, NeuN-, GFAP-, NeuN/GFAP-, NSE-, BrdU-, Wnt-, BrdU/Wnt-, VEGF-, Sox14-, VEGF/Sox14-, Sox10-, Sox2-, Sox10/Sox2-, Bax-, and Bcl-xL-positive cells was performed in the subventricular zone (SVZ), hippocampus, and cerebral cortex of rat brains on 90th day after intracerebroventricular (i.c.v.) single injection of a fraction of β-amyloid (Aβ) (1-42). The relative structural changes in these areas and disruptions to synaptic activity in the entorhinal cortex-hippocampus circuit were also evaluated. Our flow analyses revealed a reduction in the numbers of Nestin-, Vimentin-, and Nestin/Vimentin-positive cells in neurogenic niches and the olfactory bulb. These changes were accompanied by an increased number of BrdU-positive cells in the hippocampus and SVZ. The latter changes were strongly correlated with changes in the numbers of VEGF- and VEGF/Sox14-positive cells. The morphological changes were characterized by significant neural loss, a characteristic shift in entorhinal cortex-hippocampus circuit activity, and decreased spontaneous alternation in a behavioral test. We conclude that although an injection of Aβ (1-42) induced stem cell proliferation and triggered neurogenesis at a certain stage, this process was incomplete and led to neural stem cell immaturity. We propose the idea of enhancing adult neurogenesis as a promising strategy for preventing dementia at healthy elderly people andpeople at high risk for developing AD, or treating patients diagnosed with AD.

Loss-of-function parkin mutations cause oxidative stress and degeneration of dopaminergic neurons in the substantia nigra. Several consequences of parkin mutations have been described; to what degree they contribute to selective neurodegeneration remains unclear. Specific factors initiating excessive reactive oxygen species production, inefficient antioxidant capacity, or a combination are elusive. Identifying key oxidative stress contributors could inform targeted therapy. The absence of Drosophila parkin causes selective degeneration of a dopaminergic neuron cluster that is functionally homologous to the substantia nigra. By comparing observations in these to similar non-degenerating neurons, we may begin to understand mechanisms by which parkin loss of function causes selective degeneration. Using mitochondrially targeted redox-sensitive GFP2 fused with redox enzymes, we observed a sustained increased mitochondrial hydrogen peroxide levels in vulnerable dopaminergic neurons of parkin-null flies. Only transient increases in hydrogen peroxide were observed in similar but non-degenerating neurons. Glutathione redox equilibrium is preferentially dysregulated in vulnerable neuron mitochondria. To shed light on whether dysregulated glutathione redox equilibrium primarily contributes to oxidative stress, we supplemented food with folic acid, which can increase cysteine and glutathione levels. Folic acid improved survival, climbing, and transiently decreased hydrogen peroxide and glutathione redox equilibrium but did not mitigate whole-brain oxidative stress.

A sensitive and rapid liquid chromatography tandem mass spectrometry (LC-MS/MS) method was established for the quantification of total and unbound concentrations of LY3214996, an extracellular signal-regulated kinase inhibitor; abemaciclib, a cyclin-dependent kinase 4/6 inhibitor; and abemaciclib active metabolites, M2 and M20, in human plasma, brain tumor, and cerebrospinal fluid samples. The method was validated over a concentration range of 0.2-500 nM within a total run time of 3.8 min using isocratic elution on a Kinetex™ F 5 column. Detection was performed on a Sciex QTRAP 6500+ mass spectrometer employing multiple reaction monitoring mode under positive electrospray ionization. The intra- and inter-batch accuracy as well as the precision of the method for all matrices was within ±20% and ≤20% at the lower limit of quantification, and within ±15% and ≤15% for other quality control levels for all analytes. The unbound fractions of drugs and metabolites in spiked and patient samples were determined using an optimized equilibrium dialysis. The validated method was successfully applied in a phase 0/2 clinical trial to assess the central nervous system penetration of LY3214996 and abemaciclib., (© 2022 The Author(s).)

Background and Purpose: The incidences of intracranial aneurysm and aneurysmal subarachnoid hemorrhage are high in postmenopausal women. Although population-based studies suggest that hormone replacement therapy is beneficial for postmenopausal women with intracranial aneurysms, estrogen replacement may no longer be recommended for the prevention of chronic diseases given its association with adverse outcomes, such as cancer and ischemic stroke. The isoflavone daidzein and its intestinal metabolite equol are bioactive phytoestrogens and potent agonists of estrogen receptors. Given their estrogenic properties, we investigated whether the isoflavones daidzein and equol are protective against the formation and rupture of intracranial aneurysms in a mouse model of the postmenopausal state., Methods: We induced intracranial aneurysms in ovariectomized adult female mice using a combination of induced systemic hypertension and a single injection of elastase into the cerebrospinal fluid. We fed the mice with an isoflavone-free diet with/without daidzein supplementation, or in a combination of intraperitoneal equol, or oral vancomycin treatment. We also used estrogen receptor beta knockout mice., Results: Both dietary daidzein and supplementation with its metabolite, equol, were protective against aneurysm formation in ovariectomized mice. The protective effects of daidzein and equol required estrogen receptor-β. The disruption of the intestinal microbial conversion of daidzein to equol abolished daidzein’s protective effect against aneurysm formation. Mice treated with equol had lower inflammatory cytokines in the cerebral arteries, suggesting that phytoestrogens modulate inflammatory processes important to intracranial aneurysm pathogenesis., Conclusions: Our study establishes that both dietary daidzein and its metabolite, equol, protect against aneurysm formation in ovariectomized female mice through the activation of estrogen receptor-β and subsequent suppression of inflammation. Dietary daidzein’s protective effect required the intestinal conversion to equol. Our results indicate the potential therapeutic value of dietary daidzein and its metabolite, equol, for the prevention of the formation of intracranial aneurysms and related subarachnoid hemorrhage.

The aim of this study was to establish a high-throughput and sensitive LC-MS/MS method for the determination of doxepin and its major active metabolite nordoxepin in human plasma. It has been designed for bioequivalence study for formulations containing 25 mg of doxepin. Doxepin and nordoxepin were extracted from human plasma samples by protein precipitation with acetonitrile by using protein precipitation 96-well plates. The analyte was separated using a Phenomenex Kinetex Biphenyl column (100 × 2.1 mm, 2.6 μm) using isocratic elution with a mobile phase of 20 mM ammonium formate (30%) and acetonitrile:methanol 3:7 v:v (70%) at a flow rate of 0.5 mL/min and an injection volume of 10 μL. The detection was performed using a triple quadrupole mass spectrometer by multiple reaction monitoring mode to monitor the precursor-to-product ion transitions of m/z 280.4 → 107.0 and 283.4 → 235.0 for doxepin and doxepin-D3, respectively, and 266.3 → 106.9 and 269.3 → 235.0 for nordoxepin and nordoxepin-D3, respectively, in positive electrospray ionization mode. The total run time was 3.5 min. The method was validated over a concentration range of 50-10,000 pg/mL using a Triple Quad 4500 MS System (Sciex) for both analytes. The developed and validated method can be successfully used to study the bioequivalence/pharmacokinetics of doxepin and nordoxepin., (© 2020 John Wiley & Sons, Ltd.)

A protein precipitation method for the determination of clobazam (CLB) and its major active metabolite N-desmethylclobazam (N-CLB) in human plasma by liquid chromatography tandem mass spectrometry (LC-MS/MS) was established. CLB and N-CLB were extracted from human plasma samples by protein precipitation with methanol. Analyte separation was done using a Phenomenex Kinetex™ Biphenyl (50 × 2.1 mm, 1.7 μm) column using isocratic elution with a mobile phase of 5 mm ammonium formate with 0.01% ammonium hydroxide (40%) and methanol (60%) at a flow rate of 0.4 mL/min and an injection volume of 10 μL. The detection was performed on a triple quadrupole mass spectrometer in multiple reaction monitoring mode to monitor the precursor-to-product ion transitions of m/z 301.1 → 259.0, 306.0 → 263.9 for CLB and CLB-D5 and 287.0 → 245.0, 292.0 → 250.0 for N-CLB and N-CLB-D5 in positive electrospray ionization mode, respectively. The method was validated over a concentration range of 2.0-750 ng/mL for CLB and 0.7-200 ng/mL for N-CLB on SCIEX Triple Quad 4500 MS System. Total run time was 5 min. This method has been designed for bioequivalence study for formulations containing 20 mg of CLB., (© 2019 John Wiley & Sons, Ltd.)