An electro‐active copolymer of methyl methacrylate and 2‐((4‐acroylpiperazine‐1‐yl)methyl)‐9H‐thioxanthene‐9‐one (poly(MMA‐co‐ThS)) was synthesized by radical polymerization. The copolymer has good ...solubility in most organic solvents, thermal stability up to 282 °C and excellent ability to form thin films on silicon wafers. Poly(MMA‐co‐ThS) films exhibited an electrochemical and electrochromic activity resulting in the formation of long‐lived radical anion states of pendant thioxanthone groups inside the film. These states exhibit optical transitions in the visible region as a broad optical absorption band, 500 < l < 900 nm (1.38<Wopt(ThS)<2.48 eV) with a maximum at lmax = 675 nm (1.84 eV). Using temperature measurements of the current‐voltage characteristics of p‐Si(100)/poly(MMA‐co‐ThS)/Al devices, it was shown that the charge transport in the film occurs by a multiphonon mechanism, which is quantitatively described by the Nasyrov‐Gritsenko model of phonon‐assisted tunneling between traps. The value of the optical transition energy of the trap, determined by the Nasyrov‐Gritsenko model, Wopt = 1.8 eV, is in a good agreement with Wopt(ThS), confirming the nature of the traps as 9H‐thioxanthen‐9‐one structures. The n++Si(100)/poly(MMA‐co‐ThS)/Al memory device exhibited a memristive effect (reversible ON/OFF switching of the device) with an initial “forming” cycle followed by repetitive memory cycles characterized by bipolar switching.
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A sample of natural thaumasite Ca
3.0
Si(OH)
6
(CO
3
)
0.9
(SO
4
)
1.1
·12.3H
2
O (N’Chwaning mine, Kalahari manganese ore field, South Africa) was studied by powder X-ray diffraction, infrared ...absorption and Raman spectroscopy, thermal analysis, and microcalorimetry. The process of thermal transformation of thaumasite was studied using the results of FTIR and Raman spectroscopy. The enthalpy of formation from elements Δ
f
H
0
(298.15 K) = −8816 ± 30 kJ/mol was determined by high-temperature melt solution calorimetry. The value of the absolute entropy was estimated, and the enthalpy and Gibbs energy of formation of thaumasite of theoretical composition were calculated: 945.4 ± 1.8 J/(mol K), −8699 ± 30 kJ/mol, −7577 ± 30 kJ/mol, respectively.
The connection between estrogenic and PI3K/AKT/mTOR signaling pathways is frequently associated with poor outcome in ER-positive breast tumors. To characterize this connection, we performed a ...phosphoproteome analysis of ER-positive MCF7 cells. DEPTOR was identified as an estrogen-regulated mTORC1 target. DEPTOR is an mTORC1/2 inhibitory protein that is degraded in response to mitogen-induced and mTOR-mediated phosphorylation. We demonstrated that estrogen-ERα transcriptionally upregulate DEPTOR expression. Thus, despite decreased stability, increased DEPTOR levels act to modulate estrogen-induced activation of mTORC1 and mTORC2.
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Highlights
•Phosphoproteome analysis identified estrogen-regulated mTORC1 targets in MCF7 cells.#x2022;Estrogen-bound ERα transcriptionally upregulates DEPTOR expression.#x2022;Elevated levels of DEPTOR modulate estrogen-induced activation of mTORC1 and mTORC2.
ER-positive breast tumors represent ∼70#x0025; of all breast cancer cases. Although their treatment with endocrine therapies is effective in the adjuvant or recurrent settings, the development of resistance compromises their effectiveness. The binding of estrogen to ERα, a transcription factor, triggers the regulation of the target genes (genomic pathway). Additionally, a cytoplasmic fraction of estrogen-bound ERα activates oncogenic signaling pathways such as PI3K/AKT/mTOR (nongenomic pathway). The upregulation of the estrogenic and the PI3K/AKT/mTOR signaling pathways are frequently associated with a poor outcome. To better characterize the connection between these two pathways, we performed a phosphoproteome analysis of ER-positive MCF7 breast cancer cells treated with estrogen or estrogen and the mTORC1 inhibitor rapamycin. Many proteins were identified as estrogen-regulated mTORC1 targets and among them, DEPTOR was selected for further characterization. DEPTOR binds to mTOR and inhibits the kinase activity of both mTOR complexes mTORC1 and mTORC2, but mitogen-activated mTOR promotes phosphorylation-mediated DEPTOR degradation. Although estrogen enhances the phosphorylation of DEPTOR by mTORC1, DEPTOR levels increase in estrogen-stimulated cells. We demonstrated that DEPTOR accumulation is the result of estrogen-ERα-mediated transcriptional upregulation of DEPTOR expression. Consequently, the elevated levels of DEPTOR partially counterbalance the estrogen-induced activation of mTORC1 and mTORC2. These results underscore the critical role of estrogen-ERα as a modulator of the PI3K/AKT/mTOR signaling pathway in ER-positive breast cancer cells. Additionally, these studies provide evidence supporting the use of dual PI3K/mTOR or dual mTORC1/2 inhibitors in combination with endocrine therapies as a first-line treatment option for the patients with ER-positive advanced breast cancer.
The changes of P300 parameters (lower amplitude and increased latency) are thought to be the most prominent phenomena of schizophrenia. A role of gene polymorphism in P300 generation was supported by ...several associative studies in psychiatrically well subjects and patients with mental disorders. We studied P300 parameters and the following polymorphisms: T102C for the serotonin receptor type 2A (5-HTR2A) gene, the 5-HTTLPR for the serotonin transporter gene, -809G/A, -616G/C N -52C/T SNPs in the promoter region of the dopamine D4 receptor (DRD4) gene and the Val158Met polymorphism of the catechol-O-methyltransferase (COMT) in 74 patients with schizophrenia and spectrum disorders and 71 their first-degree relatives. No association was found between serotonergic system genes and P300. The -809G/A DRD4 gene polymorphism was related to amplitude in all frontal leads (p=0,01) in patients. In relatives, an association was observed between -521C/T DRD4 variants and latency (p=0,005) as well as between the COMT gene polymorphism and P300 amplitude (p=0,004) at the central lead. Thus, the genes involved in dopaminergic system play a role in P300 generation both in patients with schizophrenia and spectrum disorders and their relatives.
The synaptosomal-associated protein (SNAP-25) plays an integral role in synaptic transmission and in memory consolidation in the hippocampus. Recently an association between SNAP-25 gene polymorphism ...and cognitive ability has been reported in two independent studies of healthy people and patients with schizophrenia. Authors carried out an association study of MnlI SNAP-25 polymorphism and performance on neurocognitive tests measuring verbal memory, attention/executive functions in 66 patients with major psychosis, 75 their relatives and 136 controls. MANCOVA revealed a significant effect of group (small er, Cyrillic=0,00001) and genotype (small er, Cyrillic=0,012) as well as an interaction effect between group and genotype (small er, Cyrillic=0,02) on the performance on neurocognitive tests. Carriers of the TT genotype performed worse on the most tasks compared to other genotypes. The similar character of the MnlI SNAP-25 polymorphism effect on the variability of neurocognitive traits in all groups suggests the relationship between this gene and general cognitive ability.
THe memristor is a key memory element for neuromorphic electronics and new generation flash memories. One of the most promising materials for memristor technology is silicon oxide SiOx, which is ...compatible with silicon-based technology. In this paper, the electronic structure and charge transport mechanism in a forming-free SiOx-based memristor fabricated with the plasma enhanced chemical vapor deposition method is investigated. The experimental current-voltage characteristics measured at different temperatures in high-resistance, low-resistance and intermediate states are compared with various charge transport theories. The charge transport in all states is limited by the space charge-limited current model. The trap parameters, responsible for the charge transport in a SiOx-based memristor in different states, are determined.
Current proteomic approaches include both broad discovery measurements and quantitative targeted analyses. In many cases, discovery measurements are initially used to identify potentially important ...proteins (e.g. candidate biomarkers) and then targeted studies are employed to quantify a limited number of selected proteins. Both approaches, however, suffer from limitations. Discovery measurements aim to sample the whole proteome but have lower sensitivity, accuracy, and quantitation precision than targeted approaches, whereas targeted measurements are significantly more sensitive but only sample a limited portion of the proteome. Herein, we describe a new approach that performs both discovery and targeted monitoring (DTM) in a single analysis by combining liquid chromatography, ion mobility spectrometry and mass spectrometry (LC-IMS-MS). In DTM, heavy labeled target peptides are spiked into tryptic digests and both the labeled and unlabeled peptides are detected using LC-IMS-MS instrumentation. Compared with the broad LC-MS discovery measurements, DTM yields greater peptide/protein coverage and detects lower abundance species. DTM also achieved detection limits similar to selected reaction monitoring (SRM) indicating its potential for combined high quality discovery and targeted analyses, which is a significant step toward the convergence of discovery and targeted approaches.
The coefficient of reflection and transversal Kerr effect are studied for a series of 2D magnetoplasmonic crystals based on silver, Ni
80
Fe
20
permalloy, and Si
3
N
4
silicon nitride. It is shown ...that the filling factor of the samples has a nonlinear effect on their optical and magneto-optical properties. The maximum value of the Kerr effect is 0.88% with a filling factor of 0.77.
The natural basic aqueous aluminum and iron sulfate, aluminocopiapite (Al
0.60
)
SO
4
6.03
(OH)
1.95
⋅ 19.54H
2
O (Blyava, South Urals, Russia), was studied using powder X‑ray diffraction, infrared ...and Mössbauer spectroscopy, and thermal analysis. The enthalpy of formation from the elements
(298.15 K) = −11 826 ± 58 kJ/mol was determined by high-temperature melt solution calorimetry on a Tian-Calvet high-temperature heat-flux microcalorimeter “Setaram” (France). Standard entropies and Gibbs energies of formation were estimated for the studied aluminocopiapite and other copiapite-group minerals.
The oxidation state of Mn is determined for the first time by iodine titrimetry, and the Mn
4+
/Mn
3+
ratio (54/46%) is identified for Mn-sturmanite from the N’Chwaning 2 Mine (Kalahari manganese ...field, South Africa). The Mössbauer spectrum of sturmanite, which contains a single asymmetric Lorentz doublet with parameters
RT
IS
α-Fe
= 0.31(1) mm/s,
RT
QS = 0.18(1) mm/s, FWHM
L
= 0.55 mm/s, and FWHM
R
= 0.33 mm/s, confirms the presence of Fe
3+
only in the composition of the mineral. The process of its thermal transformation is studied using thermal analysis and IR spectroscopy: dehydration and decomposition of Ca polyhedra, dehydroxylation, decarbonatization, and complete decomposition of structure with the formation of anhydrite, hematite, and Ca borates occur up to 200, 600, 750, and 1000°C, respectively. The chemical formula of the studied sturmanite, which is calculated on the basis of our studies per eight cations, is as follows: Ca
5.94
Al
0.03
Si
0.02
B(OH)
4
1.00
B(OH)
3
0.11
SO
4
2.32
СО
3
0.49
(OH)
12
⋅22.7H
2
O. The unit cell parameters of the mineral are determined using X-ray powder diffraction:
a
= 11.148(3) Å,
c
= 21.830(9) Å, and
V
= 2349(2) Å
3
. The unit cell parameters of minerals of the sturmanite–jouravskite series linearly decrease with an increasing mole amount of the jouravskite endmember. It is suggested that the studied mineral can be an intermediate member of the sturmanite–jouravskite series with heterovalent isomorphic substitution according to following schemes: Mn
3+
and Mn
4+
→ Fe
3+
in the cation octahedral site and CO
3
2–
→ B(OH)
4
–
and SO
4
2–
in the anion site.
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