Articoli di riviste: "Complexe EDA"

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Shih, Ming-Kuei, You-Lin Tain, Chiu-Min Cheng, Chien-Ning Hsu, Yu-Wei Chen, Hung-Tse Huang, Chi-I. Chang e Chih-Yao Hou. "Separation and Identification of Resveratrol Butyrate Ester Complexes and Their Bioactivity in HepG2 Cell Models". International Journal of Molecular Sciences 22, n. 24 (17 dicembre 2021): 13539. http://dx.doi.org/10.3390/ijms222413539.

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Resveratrol butyrate ester (RBE) complexes have demonstrated higher antioxidant capacity and anti-fat accumulation activity in previous studies. In this study, silica gel, high-performance liquid chromatography, and 1H nuclear magnetic resonance were used for separation and identification of RBE complex components. With the exception of resveratrol, five different structures of ester derivatives were separated from silica gel: 3,4′-di-O-butanoylresveratrol (ED2, 18.8%), 3-O-butanoylresveratrol (ED4, 35.7%), 4′-O-butanoylresveratrol (ED5, 4.4%), 3,5,4′-tri-O-butanoylresveratrol (ED6, 1.5%), and 3,5-di-O-butanoylresveratrol (ED7, 0.7%). Among the ester derivatives obtained, ED2 and ED4 were the main ester derivatives in the RBE complex. Thus, the cellular antioxidant activities of the RBE mixture, ED2, and ED4 were evaluated. Results showed that the antioxidant capacity of ED2 and ED4 was higher than that of the RBE mixture, demonstrating that the number and position of butyrate esterification sites are related to cell survival rate and antioxidant capacity. This study is the first to report the successful isolation, structural identification, and cellular biological antioxidant activity of RBE complex derivatives, which are key characteristics for the potential practical application of RBE complexes.

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Adaileh, Fedaa. "Crosslinking of Water-Soluble Cyclodextrin with Hyaluronic Acid for Targeted Drug Delivery". Jordan Journal of Pharmaceutical Sciences 16, n. 2 (24 luglio 2023): 558. http://dx.doi.org/10.35516/jjps.v16i2.1497.

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Introduction: Most of the cytotoxic anticancer drugs belong to substances with both low solubility in aqueous fluids and poor cellular uptake, which lead to lack of specific therapy with apparent side effects. Therefore, there is a need to develop a novel drug delivery that can remotely and selectively release their payload. Curcumin(CUR) is an antibiotic, also a powerful inhibitor of the proliferation of several tumor cells. Aims: The aim of the present work is to highlight and discussed hyaluronic acid (HA ) to be grafted with Mono-6-deoxyl-6-ethylenediamino-γ-cyclodextrin (ɣ-CD-EDA) to shape a hydrogel that ought to structure inclusion complexes with curcumin, bettering its water-solubility and serving as a model drug delivery system Methods: Distinct copolymers had been organized HA grafted with ɣ-cyclodextrin (ɣ-CD-EDA) to form a hydrogel with various HA: ɣ-CD-EDA ratios and characterized, by means of 1H-NMR spectroscopy, zeta potential, Thermogravimetry analysis) TGA) Differential scanning calorimetry (DSC), and transmission electron microscopy (TEM). Furthermore, drug loading Encapsulation efficiency (EE%), and release kinetics, and stability. Also, cytotoxicity and uptake were assessed by flow cytometry, MTT assay and confocal laser microscopy. Wound healing activity was once improved using three cell MDA-MB-231, MCF-7, and fibroblast. Measuring the effect of HA-γ-CD-EDA1-CUR, γ-CD-EDA1-CUR, and CUR free on the Production and Secretion of inflammatory cytokines Result: CUR loading potential used to be at once correlated with extended HA-ɣ-CD-EDA composition and morphological adjustments have been discovered upon CUR binding. The host substances and their CUR inclusion complexes are no longer cytotoxic, and consequently beneficial for CUR and drug delivery. Moreover, HA-γ-CD-EDA1-CUR, γ-CD-EDA1-CUR, and CUR wound healing activity was once improved, and human promonocytic THP-1 cells produce inflammatory mediators such as IL-1β, IL10,IL8, TNF-α,IRAKI and IL6 results showed that the combination HA-γ-CD-EDA1-CUR could be suitable to reduce inflammation and the complex promoted the anti-inflammatory effect by the inhibition of inflammatory mediators. Conclusion: HA grafted with ɣ-cyclodextrin (ɣ-CD-EDA) to form a hydrogel was designed, formulated, and full characterized. Nanoparticles were stable at physiological pH and have released payload. Encapsulation of CUR into polymer increased its selectivity, distribution, and accumulation into the cancer cells. HA-CD-EDA1conjugated curcumin if incorporated in suitable matrix has a potential utility for treatment of wound, and down regulation in THP-1 cells.

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Yang, Zhonglie, Yutong Liu, Kun Cao, Xiaobin Zhang, Hezhong Jiang e Jiahong Li. "Synthetic reactions driven by electron-donor–acceptor (EDA) complexes". Beilstein Journal of Organic Chemistry 17 (6 aprile 2021): 771–99. http://dx.doi.org/10.3762/bjoc.17.67.

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The reversible, weak ground-state aggregate formed by dipole–dipole interactions between an electron donor and an electron acceptor is referred to as an electron-donor–acceptor (EDA) complex. Generally, upon light irradiation, the EDA complex turns into the excited state, causing an electron transfer to give radicals and to initiate subsequent reactions. Besides light as an external energy source, reactions involving the participation of EDA complexes are mild, obviating transition metal catalysts or photosensitizers in the majority of cases and are in line with the theme of green chemistry. This review discusses the synthetic reactions concerned with EDA complexes as well as the mechanisms that have been shown over the past five years.

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Gromowski, Gregory D., Nicholas D. Barrett e Alan D. T. Barrett. "Characterization of Dengue Virus Complex-Specific Neutralizing Epitopes on Envelope Protein Domain III of Dengue 2 Virus". Journal of Virology 82, n. 17 (18 giugno 2008): 8828–37. http://dx.doi.org/10.1128/jvi.00606-08.

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ABSTRACT The surface of the mature dengue virus (DENV) particle is covered with 180 envelope (E) proteins arranged as homodimers that lie relatively flat on the virion surface. Each monomer consists of three domains (ED1, ED2, and ED3), of which ED3 contains the critical neutralization determinant(s). In this study, a large panel of DENV-2 recombinant ED3 mutant proteins was used to physically and biologically map the epitopes of five DENV complex-specific monoclonal antibodies (MAbs). All five MAbs recognized a single antigenic site that includes residues K310, I312, P332, L389, and W391. The DENV complex antigenic site was located on an upper lateral surface of ED3 that was distinct but overlapped with a previously described DENV-2 type-specific antigenic site on ED3. The DENV complex-specific MAbs required significantly higher occupancy levels of available ED3 binding sites on the virion, compared to DENV-2 type-specific MAbs, in order to neutralize virus infectivity. Additionally, there was a great deal of variability in the neutralization efficacy of the DENV complex-specific MAbs with representative strains of the four DENVs. Overall, the differences in physical binding and potency of neutralization observed between DENV complex- and type-specific MAbs in this study demonstrate the critical role of the DENV type-specific antibodies in the neutralization of virus infectivity.

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Rodriguez-Parada, Jose M., e Virgil Percec. "Interchain EDA complexes: A model for LCST?" Journal of Polymer Science Part A: Polymer Chemistry 24, n. 3 (marzo 1986): 579–87. http://dx.doi.org/10.1002/pola.1986.080240316.

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Lin, Li, Zhonglie Yang, Jianchen Liu, Jingxia Wang, Jiale Zheng, Jun-Long Li, Xiaobin Zhang, Xiang-Wei Liu, Hezhong Jiang e Jiahong Li. "Visible-light-induced surfactant-promoted sulfonylation of alkenes and alkynes with sulfonyl chloride by the formation of an EDA-complex with NaI in water at room temperature". Green Chemistry 23, n. 15 (2021): 5467–73. http://dx.doi.org/10.1039/d1gc00956g.

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We report an efficient visible-light-induced iodosulfonyl reaction of alkenes in water using an EDA complex strategy at room temperature. The addition of a cationic surfactant allows for the easy formation of colored EDA complexes in water.

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Kwiecień, Anna, Jana Ruda-Kucerova, Kamil Kamiński, Zuzana Babinska, Iwona Popiołek, Krzysztof Szczubiałka, Maria Nowakowska e Maria Walczak. "Improved Pharmacokinetics and Tissue Uptake of Complexed Daidzein in Rats". Pharmaceutics 12, n. 2 (16 febbraio 2020): 162. http://dx.doi.org/10.3390/pharmaceutics12020162.

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The pharmacokinetic profile and tissue uptake of daidzein (DAI) was determined in rat serum and tissues (lungs, eyes, brain, heart, spleen, fat, liver, kidney, and testes) after intravenous and intraperitoneal administration of DAI in suspension or complexed with ethylenediamine-modified γ-cyclodextrin (GCD-EDA/DAI). The absolute and relative bioavailability of DAI suspended (20 mg/kg i.v. vs. 50 mg/kg i.p.) and complexed (0.54 mg/kg i.v. vs. 1.35 mg/kg i.p.) was determined. After i.p. administration, absorption of DAI complexed with GCD-EDA was more rapid (tmax = 15 min) than that of DAI in suspension (tmax = 45 min) with a ca. 3.6 times higher maximum concentration (Cmax = 615 vs. 173 ng/mL). The i.v. half-life of DAI was longer in GCD-EDA/DAI complex compared with DAI in suspension (t0.5 = 380 min vs. 230 min). The volume of distribution of DAI given i.v. in GCD-EDA/DAI complex was ca. 6 times larger than DAI in suspension (38.6 L/kg vs. 6.2 L/kg). Our data support the concept that the pharmacokinetics of DAI suspended in high doses are nonlinear. Increasing the intravenous dose 34 times resulted in a 5-fold increase in AUC. In turn, increasing the intraperitoneal dose 37 times resulted in a ca. 2-fold increase in AUC. The results of this study suggested that GCD-EDA complex may improve DAI bioavailability after i.p. administration. The absolute bioavailability of DAI in GCD-EDA inclusion complex was ca. 3 times greater (F = 82.4% vs. 28.2%), and the relative bioavailability was ca. 21 times higher than that of DAI in suspension, indicating the need to study DAI bioavailability after administration by routes other than intraperitoneal, e.g., orally, subcutaneously, or intramuscularly. The concentration of DAI released from GCD-EDA/DAI inclusion complex to all the rat tissues studied was higher than after administration of DAI in suspension. The concentration of DAI in brain and lungs was found to be almost 90 and 45 times higher, respectively, when administered in complex compared to the suspended DAI. Given the nonlinear relationship between DAI bioavailability and the dose released from the GCD-EDA complex, complexation of DAI may thus offer an effective approach to improve DAI delivery for treatment purposes, for example in mucopolysaccharidosis (MPS), allowing the reduction of ingested DAI doses.

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Jeliński, Tomasz, Maciej Przybyłek, Magdalena Mianowana, Kinga Misiak e Piotr Cysewski. "Deep Eutectic Solvents as Agents for Improving the Solubility of Edaravone: Experimental and Theoretical Considerations". Molecules 29, n. 6 (12 marzo 2024): 1261. http://dx.doi.org/10.3390/molecules29061261.

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In this study, both practical and theoretical aspects of the solubility of edaravone (EDA) in Deep Eutectic Solvents (DESs) were considered. The solubility of edaravone in some media, including water, can be limited, which creates the need for new efficient and environmentally safe solvents. The solubility of EDA was measured spectrophotometrically and the complex intermolecular interactions within the systems were studied with the COSMO-RS framework. Of the four studied DES systems, three outperformed the most efficient classical organic solvent, namely dichloromethane, with the DES comprising choline chloride and triethylene glycol, acting as hydrogen bond donor (HBD), in a 1:2 molar proportion yielding the highest solubility of EDA. Interestingly, the addition of a specific amount of water further increased EDA solubility. Theoretical analysis revealed that in pure water or solutions with high water content, EDA stacking is responsible for self-aggregation and lower solubility. On the other hand, the presence of HBDs leads to the formation of intermolecular clusters with EDA, reducing self-aggregation. However, in the presence of a stoichiometric amount of water, a three-molecular EDA–HBD–water complex is formed, which explains why water can also act as a co-solvent. The high probability of formation of this type of complexes is related to the high affinity of the components, which exceeds all other possible complexes.

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Edulji, S. K., e S. T. Nguyen. "Substrate scope in the olefin cyclopropanation reaction catalyzed by m-oxo-bis[(salen)iron(III)] complexes". Pure and Applied Chemistry 76, n. 3 (1 gennaio 2004): 645–49. http://dx.doi.org/10.1351/pac200476030645.

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The cyclopropanation of various alkenes with different diazoester compounds was investigated using two different μ-oxo-bis[(salen)iron(III)] complexes, [Fe(3,3',5,5'-tBu4salen)]2O and [Fe(salen)]2O. Ethyl diazoacetate (EDA), tert-butyl diazoacetate (tBDA), and ethyl diazoacetoacetate (EDAA) were used with mono- and disubstituted terminal olefins (styrene and 1,1-diphenyl ethylene, respectively), internal olefin (trans-β-methyl styrene), and an electron-rich alkene (n-butyl vinyl ether). Moderate-to-good cyclopropanation yields were obtained for most substrates.

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Singh, Joaquín O., Jorge D. Anunziata e Juana J. Silber. "n–π Electron donor–acceptor complexes. II. Aliphatic amines with dinitrobenzenes". Canadian Journal of Chemistry 63, n. 4 (1 aprile 1985): 903–7. http://dx.doi.org/10.1139/v85-150.

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The interaction of several aliphatic amines as n-donors and dinitrobenzenes (DNB) as π-acceptors has been studied in n-hexane. The formation of electron donor – acceptor (EDA) complexes is proposed to explain the spectroscopic behaviour of the mixtures. The stability constants (Ks) for these complexes have been calculated by an iterative procedure. For a given acceptor, the donor strength of RNH2 > R2NH > R3N was found. This order is explained by considering the role that steric effect may play in the EDA complex formation. On the other hand, the fact that for a given donor Ks follows the order 1,2-DNB > 1,3-DNB > 1,4-DNB, and that 1,2-DNB reacts with primary amines, led to the proposal of orientational complexes. These EDA complexes may be considered intermediates in aromatic nucleophilic substitution reactions.

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Tkachev, V. A., E. I. Mal’tsev, A. V. Vannikov, A. Yu Kryukov, H. H. Hörhold e J. Klee. "Laser photolysis of polymer EDA complexes including 4,4′-diaminodiphenylmethane derivatives". Research on Chemical Intermediates 13, n. 1 (gennaio 1990): 7–16. http://dx.doi.org/10.1163/156856790x00021.

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Biasutti, M. A., e Juana J. Silber. "Interaction between tetracyanoethylene and naphthalene in reverse micelles of AOT in n-hexane. The electron-donor properties of AOT". Canadian Journal of Chemistry 74, n. 9 (1 settembre 1996): 1603–8. http://dx.doi.org/10.1139/v96-177.

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The electron donor–acceptor (EDA) interaction between TCNE and naphthalene (Naph) in n-hexane and reverse micelles of AOT in n-hexane was studied by UV–visible spectroscopy with the aim of determining the influence of the micellar media on the EDA interaction. The spectra of the mixtures of TCNE–Naph in n-hexane show two typical maxima at 418 and 534 nm, assigned to the formation of a π–π EDA complex. In the micellar media a new band is observed at 398 nm. When the spectra of TCNE in n-hexane are studied in the presence of AOT two new bands at 398 and 418 nm are detected. These bands are consistent with an EDA interaction between TCNE and AOT as n-donor. The stability constants of this interaction were calculated for AOT concentrations below the CMC and in the micellar media at different W(W = [H2O]/[AOT]). The results give evidence of the tendency of AOT to interact very strongly with electron acceptors. Moreover, in the system TCNE–Naph in the micellar media it is shown that Naph and AOT compete to form a complex with TCNE. The formation constants of the complexes of AOT–Naph in the micelle system were determined at W = 0 and 5. Despite the competition of AOT for TCNE the stability constant for the complex TCNE–Naph is higher than in homogeneous media, probably due to the high local concentration of the acceptor in the micelle. Key words: reverse micelles, aerosol-OT, tetracyanoethylene, naphthalene, electron donor–acceptor complexes.

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Zon, M. A., H. Fernandez, L. Sereno e J. J. Silber. "The kinetics of formation of electron donor–acceptor complexes. A temperature-jump study". Canadian Journal of Chemistry 68, n. 2 (1 febbraio 1990): 278–81. http://dx.doi.org/10.1139/v90-038.

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The kinetics of the Electron Donor–Acceptor (EDA) complex between N,N,N′,N′-tetramethyl-p-phenylenediamine and m-dinitrobenzene in acetonitrile has been studied by the temperature-jump technique. The magnitude of the rate constants of association and dissociation, although relatively large, is well below the diffusion control values. The calculated rates closely coincide with those obtained by chronoamperometry. An entropy control is suggested for this reaction. The results obtained in this work are useful to demonstrate that the concept about EDA complexes being formed by diffusion-controlled reactions should not be generalized. Keywords: electron donor–acceptor complexes, m-dinitrobenzene, N,N,N′,N′-tetramethyl-p-phenylenediamine, T-jump, kinetics.

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Pereira, Juscélia C., Luciana M. Lima, Rita C. Alfenas, Ana P. M. Guttierres, Manuel Sillero-Quintana, Hamilton H. T. Teis e João C. B. Marins. "Consumption of energy drinks on cardiovascular and metabolic response and performance. Is there an effect?" Archivos de Medicina del Deporte 39, n. 4 (29 settembre 2022): 222–28. http://dx.doi.org/10.18176/archmeddeporte.00094.

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Over the years, the search for nutritional strategies that promote improved sports performance has increased. Among the available options, energy drinks appear as potential nutritional resources for this purpose, because they offer, in addition to caffeine, substances that act synergistically to improve performance, such as taurine, carbohydrates, amino acids, vitamins and minerals, promoting improved performance for both amateur and professional athletes. The aim of the study was to verify the effects of ingesting energy drinks with (ED1) and without carbohydrates (ED0) containing 2 mg·kg-1 of caffeine, and a decaffeinated placebo (PL) on cardiovascular, metabolic and performance parameters during cycling. Twelve male cyclists (age = 24.4 ± 6.6 years old) volunteered to participate in this study. The protocol consisted of three experimental sessions of 60 min of continuous cycling (65-75% of VO2maxE) followed by time-trial 6 km. The subjects ingested ED1, ED0 or a placebo drink (PL) 40 min before beginning the exercise. The heart rate (HR), blood pressure (BP), plasma glucose and lactate concentrations, and the time taken to complete the 6 km time-trial were evaluated. The time taken to complete the time-trial was significantly higher (p < 0.05) in the PL group than in the groups ED1 and ED0. This time significantly decreased after the ED1 consumption relative to that for the ED0 consumption. Heart rate, systolic and diastolic arterial pressure and in the plasma glucose and lactate concentrations were similar in all the considered groups. These results demonstrate that ED1 consumption appears to be more effective at maximizing performance during the last 6 km.

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Sima, Jian, Zhijiang Yan, Yaohui Chen, Elin Lehrmann, Yongqing Zhang, Ramaiah Nagaraja, Weidong Wang, Zhong Wang e David Schlessinger. "Eda-activated RelB recruits an SWI/SNF (BAF) chromatin-remodeling complex and initiates gene transcription in skin appendage formation". Proceedings of the National Academy of Sciences 115, n. 32 (23 luglio 2018): 8173–78. http://dx.doi.org/10.1073/pnas.1800930115.

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Ectodysplasin A (Eda) signaling activates NF-κB during skin appendage formation, but how Eda controls specific gene transcription remains unclear. Here, we find that Eda triggers the formation of an NF-κB–associated SWI/SNF (BAF) complex in which p50/RelB recruits a linker protein, Tfg, that interacts with BAF45d in the BAF complex. We further reveal that Tfg is initially induced by Eda-mediated RelB activation and then bridges RelB and BAF for subsequent gene regulation. The BAF component BAF250a is particularly up-regulated in skin appendages, and epidermal knockout of BAF250a impairs skin appendage development, resulting in phenotypes similar to those of Eda-deficient mouse models. Transcription profiling identifies several target genes regulated by Eda, RelB, and BAF. Notably, RelB and the BAF complex are indispensable for transcription of Eda target genes, and both BAF complex and Eda signaling are required to open chromatin of Eda targets. Our studies thus suggest that Eda initiates a signaling cascade and recruits a BAF complex to specific gene loci to facilitate transcription during organogenesis.

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Neelgund, Gururaj M., Abhay S. Kulkarni e M. L. Budni. "EDA Complexes of 2,3-Dichloro-1,4-naphthoquinone with Some Substituted Anilines". Monatshefte f�r Chemie / Chemical Monthly 135, n. 4 (1 aprile 2004): 343–55. http://dx.doi.org/10.1007/s00706-003-0128-8.

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Jamróz, M. H., J. Cz Dobrowolski, K. Bajdor e M. A. Borowiak. "Ab initio study of the ν(CO2) mode in EDA complexes". Journal of Molecular Structure 349 (aprile 1995): 9–12. http://dx.doi.org/10.1016/0022-2860(95)08696-s.

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Dolenc, Darko, e Barbara Modec. "EDA Complexes of N-halosaccharins with N- and O-donor ligands". New Journal of Chemistry 33, n. 11 (2009): 2344. http://dx.doi.org/10.1039/b9nj00263d.

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Shivji, M. K., e N. B. La Thangue. "Multicomponent differentiation-regulated transcription factors in F9 embryonal carcinoma stem cells". Molecular and Cellular Biology 11, n. 3 (marzo 1991): 1686–95. http://dx.doi.org/10.1128/mcb.11.3.1686-1695.1991.

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Murine F9 embryonal carcinoma (F9 EC) stem cells have an E1a-like transcription activity that is down-regulated as these cells differentiate to parietal endoderm. For the adenovirus E2A promoter, this activity requires at least two sequence-specific transcription factors, one that binds the cyclic AMP-responsive element (CRE) and the other, DRTF1, the DNA-binding activity of which is down-regulated as F9 EC cells differentiate. Here we report the characterization of several binding activities in F9 EC cell extracts, referred to as DRTF 1a, 1b and 1c, that recognize the DRTF1 cis-regulatory sequence (-70 to -50 region). These activities can be chromatographically separated but are not distinguishable by DNA sequence specificity. Activity 1a is a detergent-sensitive complex in which DNA binding is regulated by phosphorylation. In contrast, activities 1b and 1c are unaffected by these treatments but exist as multicomponent protein complexes even before DNA binding. Two sets of DNA-binding polypeptides, p50DR and p30DR, affinity purified from F9 EC cell extracts produce complexes 1b and 1c. Both polypeptides appear to be present in the same DNA-bound protein complex and both directly contact DNA. These affinity-purified polypeptides activate transcription in vitro in a binding-site-dependent manner. These data indicate the in F9 EC stem cells, multicomponent differentiation-regulated transcription factors contribute to the cellular E1a-like activity.

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Shivji, M. K., e N. B. La Thangue. "Multicomponent differentiation-regulated transcription factors in F9 embryonal carcinoma stem cells." Molecular and Cellular Biology 11, n. 3 (marzo 1991): 1686–95. http://dx.doi.org/10.1128/mcb.11.3.1686.

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Murine F9 embryonal carcinoma (F9 EC) stem cells have an E1a-like transcription activity that is down-regulated as these cells differentiate to parietal endoderm. For the adenovirus E2A promoter, this activity requires at least two sequence-specific transcription factors, one that binds the cyclic AMP-responsive element (CRE) and the other, DRTF1, the DNA-binding activity of which is down-regulated as F9 EC cells differentiate. Here we report the characterization of several binding activities in F9 EC cell extracts, referred to as DRTF 1a, 1b and 1c, that recognize the DRTF1 cis-regulatory sequence (-70 to -50 region). These activities can be chromatographically separated but are not distinguishable by DNA sequence specificity. Activity 1a is a detergent-sensitive complex in which DNA binding is regulated by phosphorylation. In contrast, activities 1b and 1c are unaffected by these treatments but exist as multicomponent protein complexes even before DNA binding. Two sets of DNA-binding polypeptides, p50DR and p30DR, affinity purified from F9 EC cell extracts produce complexes 1b and 1c. Both polypeptides appear to be present in the same DNA-bound protein complex and both directly contact DNA. These affinity-purified polypeptides activate transcription in vitro in a binding-site-dependent manner. These data indicate the in F9 EC stem cells, multicomponent differentiation-regulated transcription factors contribute to the cellular E1a-like activity.

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Mao, Yuezhi, Matthias Loipersberger, Paul R. Horn, Akshaya Das, Omar Demerdash, Daniel S. Levine, Srimukh Prasad Veccham, Teresa Head-Gordon e Martin Head-Gordon. "From Intermolecular Interaction Energies and Observable Shifts to Component Contributions and Back Again: A Tale of Variational Energy Decomposition Analysis". Annual Review of Physical Chemistry 72, n. 1 (20 aprile 2021): 641–66. http://dx.doi.org/10.1146/annurev-physchem-090419-115149.

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Quantum chemistry in the form of density functional theory (DFT) calculations is a powerful numerical experiment for predicting intermolecular interaction energies. However, no chemical insight is gained in this way beyond predictions of observables. Energy decomposition analysis (EDA) can quantitatively bridge this gap by providing values for the chemical drivers of the interactions, such as permanent electrostatics, Pauli repulsion, dispersion, and charge transfer. These energetic contributions are identified by performing DFT calculations with constraints that disable components of the interaction. This review describes the second-generation version of the absolutely localized molecular orbital EDA (ALMO-EDA-II). The effects of different physical contributions on changes in observables such as structure and vibrational frequencies upon complex formation are characterized via the adiabatic EDA. Example applications include red- versus blue-shifting hydrogen bonds; the bonding and frequency shifts of CO, N2, and BF bound to a [Ru(II)(NH3)5]2 + moiety; and the nature of the strongly bound complexes between pyridine and the benzene and naphthalene radical cations. Additionally, the use of ALMO-EDA-II to benchmark and guide the development of advanced force fields for molecular simulation is illustrated with the recent, very promising, MB-UCB potential.

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Moubayed, Abdallah. "A Complete EDA and DL Pipeline for Softwarized 5G Network Intrusion Detection". Future Internet 16, n. 9 (10 settembre 2024): 331. http://dx.doi.org/10.3390/fi16090331.

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The rise of 5G networks is driven by increasing deployments of IoT devices and expanding mobile and fixed broadband subscriptions. Concurrently, the deployment of 5G networks has led to a surge in network-related attacks, due to expanded attack surfaces. Machine learning (ML), particularly deep learning (DL), has emerged as a promising tool for addressing these security challenges in 5G networks. To that end, this work proposed an exploratory data analysis (EDA) and DL-based framework designed for 5G network intrusion detection. The approach aimed to better understand dataset characteristics, implement a DL-based detection pipeline, and evaluate its performance against existing methodologies. Experimental results using the 5G-NIDD dataset showed that the proposed DL-based models had extremely high intrusion detection and attack identification capabilities (above 99.5% and outperforming other models from the literature), while having a reasonable prediction time. This highlights their effectiveness and efficiency for such tasks in softwarized 5G environments.

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Muro, Andrés F., Massimo Caputi, Rajalakshmi Pariyarath, Franco Pagani, Emanuele Buratti e Francisco E. Baralle. "Regulation of Fibronectin EDA Exon Alternative Splicing: Possible Role of RNA Secondary Structure for Enhancer Display". Molecular and Cellular Biology 19, n. 4 (1 aprile 1999): 2657–71. http://dx.doi.org/10.1128/mcb.19.4.2657.

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ABSTRACT The fibronectin primary transcript undergoes alternative splicing in three noncoordinated sites: the cassette-type EDA and EDB exons and the more complex IIICS region. We have shown previously that an 81-nucleotide region within the EDA exon is necessary for exon recognition and that this region contains at least two splicing-regulatory elements: a polypurinic enhancer (exonic splicing enhancer [ESE]) and a nearby silencer element (exonic splicing silencer [ESS]). Here, we have analyzed the function of both elements in different cell types. We have mapped the ESS to the nucleotide level, showing that a single base change is sufficient to abolish its function. Testing of the ESE and ESS elements in heterologous exons, individually or as part of the complete EDA regulatory region, showed that only the ESE element is active in different contexts. Functional studies coupled to secondary-structure enzymatic analysis of the EDA exon sequence variants suggest that the role of the ESS element may be exclusively to ensure the proper RNA conformation and raise the possibility that the display of the ESE element in a loop position may represent a significant feature of the exon splicing-regulatory region.

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24

Hamity, M., e R. H. Lema. "The photochemistry of electron donor–acceptor (EDA) complexes in micellar solutions. I. The stilbene–methylviologen system". Canadian Journal of Chemistry 66, n. 7 (1 luglio 1988): 1552–57. http://dx.doi.org/10.1139/v88-252.

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Abstract (sommario):

The association constants for the electron donor–acceptor (EDA) complexes formed between both cis-stilbene (cS) and trans-stilbene (tS) as donors and methylviologen (MV+2) as acceptor were determined in ethanol and micellar sodium dodecyl sulfate (SDS) solutions in the range of SDS concentration 0.05–0.1 M. The values obtained in micellar solutions were much higher than those in ethanol and were heavily dependent upon SDS concentration. This effect is due to an increase in the local concentration of the reactants in the micellar pseudophase. The tS fluorescence quenching by MV+2 was also studied in the same solvent media. In ethanol, the Stern–Volmer plot was found to be linear, with quenching constant (KSV) similar to the association constant determined by the absorption method. In micellar solutions, although upward curvature of the Stern–Volmer plots was observed, a reaction scheme based on static quenching via ground state EDA complex is proposed, which explains the experimental results. Irradiation in the absorption band of the EDA complexes formed by tS or cS and MV+2 was carried out in ethanol and SDS solutions, in the absence of oxygen. Only cis–trans isomerization of cS in SDS solution was observed, with a quantum yield value of Φcis = 0.012.

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25

Ciarrocchi, Carlo, Guido Colucci, Massimo Boiocchi, Donatella Sacchi, Maduka L. Weththimuni, Alessio Orbelli Biroli e Maurizio Licchelli. "Interligand Charge-Transfer Processes in Zinc Complexes". Chemistry 4, n. 3 (21 luglio 2022): 717–34. http://dx.doi.org/10.3390/chemistry4030051.

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Abstract (sommario):

Electron donor–acceptor (EDA) complexes are characterized by charge-transfer (CT) processes between electron-rich and electron-poor counterparts, typically resulting in a new absorption band at a higher wavelength. In this paper, we report a series of novel 2,6-di(imino)pyridine ligands with different electron-rich aromatic substituents and their 1:2 (metal/ligand) complexes with zinc(II) in which the formation of a CT species is promoted by the metal ion coordination. The absorption properties of these complexes were studied, showing the presence of a CT absorption band only in the case of aromatic substituents with donor groups. The nature of EDA interaction was confirmed by crystallographic studies, which disclose the electron-poor and electron-rich moieties involved in the CT process. These moieties mutually belong to both the ligands and are forced into a favorable spatial arrangement by the coordinative preferences of the metal ion.

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26

Leuranguer, Valérie, Robert T. Dirksen e Kurt G. Beam. "Potentiated L-type Ca2+ Channels Rectify". Journal of General Physiology 121, n. 6 (12 maggio 2003): 541–50. http://dx.doi.org/10.1085/jgp.200308833.

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Abstract (sommario):

Strong depolarization and dihydropyridine agonists potentiate inward currents through native L-type Ca2+ channels, but the effect on outward currents is less clear due to the small size of these currents. Here, we examined potentiation of wild-type α1C and two constructs bearing mutations in conserved glutamates in the pore regions of repeats II and IV (E2A/E4A-α1C) or repeat III (E3K-α1C). With 10 mM Ca2+ in the bath and 110 mM Cs+ in the pipette, these mutated channels, expressed in dysgenic myotubes, produced both inward and outward currents of substantial amplitude. For both the wild-type and mutated channels, we observed strong inward rectification of potentiation: strong depolarization had little effect on outward tail currents but caused the inward tail currents to be larger and to decay more slowly. Similarly, exposure to DHP agonist increased the amplitude of inward currents and decreased the amplitude of outward currents through both E2A/E4A-α1C and E3K-α1C. As in the absence of drug, strong depolarization in the presence of dihydropyridine agonist had little effect on outward tail currents but increased the amplitude and slowed the decay of inward tail currents. We tested whether cytoplasmic Mg2+ functions as the blocking particle responsible for the rectification of potentiated L-type Ca2+ channels. However, even after complete removal of cytoplasmic Mg2+, (−)BayK 8644 still potentiated inward current and partially blocked outward current via E2A/E4A-α1C. Although zero Mg2+ did not reveal potentiation of outward current by DHP agonist, it did have two striking effects, (a) a strong suppression of decay of both inward and outward currents via E2A/E4A-α1C and (b) a nearly complete elimination of depolarization-induced potentiation of inward tail currents. These results can be explained by postulating that potentiation exposes a binding site in the pore to which an intracellular blocking particle can bind and produce inward rectification of the potentiated channels.

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27

Asaad, Adel N., e Gunnar Aksnes. "Kinetics and Mechanism of the 2+ 2 Cycloaddition of Tetracyanoethylene to 2,5-Dimethyl-2,4-Hexadiene". Zeitschrift für Naturforschung A 43, n. 5 (1 maggio 1988): 435–41. http://dx.doi.org/10.1515/zna-1988-0507.

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The kinetics of the 2 + 2 cycloaddition reaction between tetracyanoethylene and 2,5-dimethyl- 2,4-hexadiene in different solvents has been studied by following the disappearance of the intermediate EDA-complex spectrophotometrically. It is concluded that the EDA-complex is transformed through a concerted cyclicpolar transition state to give the vinyl cyclobutane derivative (III). The effects of various solvents on the reaction rates have been analysed using a multiparameter approach. The thermodynamic parameters (ΔH0 and ΔS0), of EDA-complex formation and the activation parameters (ΔH# and ΔS#) of the cycloaddition have been discussed.

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28

Lee, Kwanyoung Y., e Jay K. Kochi. "Charge-transfer structures of aromatic EDA complexes with N-heteroatom-substituted pyridinium cations". Journal of the Chemical Society, Perkin Transactions 2, n. 7 (1992): 1011. http://dx.doi.org/10.1039/p29920001011.

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29

Takemura, Hiroyuki, Saori Nakata, Akiko Inoue e Ayaka Mishima. "Synthesis of a hexacationic cyclophane and formation of EDA-type host–guest complexes". Journal of Inclusion Phenomena and Macrocyclic Chemistry 77, n. 1-4 (18 aprile 2013): 483–87. http://dx.doi.org/10.1007/s10847-013-0321-2.

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30

Spange, Stefan, Annett Fährmann, Anett Reuter, Ralph Walther e Yvonne Zimmermann. "Solvatochromism of carbenium-arene EDA (electrondonor-acceptor) complexes and their behaviour on silica". Journal of Physical Organic Chemistry 14, n. 5 (12 marzo 2001): 271–83. http://dx.doi.org/10.1002/poc.360.

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31

An, Xiao-De, Hui-Yun Wang, Long-Xue Wang, Wen-Tao Jiang, Jia-Jun Xu, Qing-Quan Sheng, Qixue Qin e Ying Fu. "Visible-light-induced hydrosulfonylation of alkynes driven by electron-donor–acceptor (EDA) complexes". Tetrahedron Letters 153 (dicembre 2024): 155368. http://dx.doi.org/10.1016/j.tetlet.2024.155368.

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32

Ikeda, M. A., e J. R. Nevins. "Identification of distinct roles for separate E1A domains in disruption of E2F complexes". Molecular and Cellular Biology 13, n. 11 (novembre 1993): 7029–35. http://dx.doi.org/10.1128/mcb.13.11.7029-7035.1993.

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Abstract (sommario):

The adenovirus E1A protein can disrupt protein complexes containing the E2F transcription factor in association with cellular regulatory proteins such as the retinoblastoma gene product (Rb) and the Rb-related p107 protein. Previous experiments have shown that the CR1 and CR2 domains of E1A are required for this activity. We now demonstrate that the CR2 domain is essential for allowing E1A to interact with the E2F-Rb or the E2F-p107-cyclin A-cdk2 complex. Multimeric complexes containing E1A can be detected when the CR1 domain has been rendered inactive by mutation. In addition, the E1A CR1 domain, but not the CR2 domain, is sufficient to prevent the interaction of E2F with Rb or p107. On the basis of these results, we suggest a model whereby the CR2 domain brings E1A to the E2F complexes and then, upon a normal equilibrium dissociation of Rb or p107 from E2F, the E1A CR1 domain is able to block the site of interaction on Rb or p107, thereby preventing the re-formation of the complexes.

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33

Ikeda, M. A., e J. R. Nevins. "Identification of distinct roles for separate E1A domains in disruption of E2F complexes." Molecular and Cellular Biology 13, n. 11 (novembre 1993): 7029–35. http://dx.doi.org/10.1128/mcb.13.11.7029.

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Abstract (sommario):

The adenovirus E1A protein can disrupt protein complexes containing the E2F transcription factor in association with cellular regulatory proteins such as the retinoblastoma gene product (Rb) and the Rb-related p107 protein. Previous experiments have shown that the CR1 and CR2 domains of E1A are required for this activity. We now demonstrate that the CR2 domain is essential for allowing E1A to interact with the E2F-Rb or the E2F-p107-cyclin A-cdk2 complex. Multimeric complexes containing E1A can be detected when the CR1 domain has been rendered inactive by mutation. In addition, the E1A CR1 domain, but not the CR2 domain, is sufficient to prevent the interaction of E2F with Rb or p107. On the basis of these results, we suggest a model whereby the CR2 domain brings E1A to the E2F complexes and then, upon a normal equilibrium dissociation of Rb or p107 from E2F, the E1A CR1 domain is able to block the site of interaction on Rb or p107, thereby preventing the re-formation of the complexes.

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34

Theuerkauf, Martin, e John Couwenberg. "The extended downscaling approach: A new R-tool for pollen-based reconstruction of vegetation patterns". Holocene 27, n. 8 (1 dicembre 2016): 1252–58. http://dx.doi.org/10.1177/0959683616683256.

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Abstract (sommario):

The extended downscaling approach (EDA) is a quantitative method in palynology that aims to detect past vegetation patterns and communities in the landscape. The EDA uses iterative forward modelling to fit vegetation composition to robust landscape patterns by comparing simulated with actually observed pollen deposition. The approach employs a set of pollen records, preferably from medium sized to large lakes or peatlands, as well as maps of robust landscape patterns, such as soils and relief. So far, the EDA has been applied in simple settings with only few taxa. To be able to apply the model also in more complex situations, we have implemented the EDA in the R environment for statistical computing. We here test the performance of the EDAinR function in five synthetic scenarios of increasing complexity. In all cases, the EDA is well able to reconstruct vegetation composition, also on rare landscape units. If uncertainty is added both to the pollen data and pollen productivity estimates, the EDA still correctly reconstructs species composition on more than 90% of the total landscape in all scenarios, underlining that the EDA performs well also in complex settings. The EDAinR function will be available within the R package DISQOVER.

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35

Abdel-Hamid, Refat, Ahmed A. El-Samahy, Abdel-Hafiz El-Taher e Hussein El-Sagher. "Spectral studies on the interaction of iodine with thiazoles". Canadian Journal of Chemistry 65, n. 3 (1 marzo 1987): 468–72. http://dx.doi.org/10.1139/v87-081.

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Abstract (sommario):

The electron donor–acceptor molecular complexes between thiazole and some of its derivatives and iodine in several solvents have been investigated spectrophotometrically at different temperatures. Spectral characteristics, equilibrium constants, K, extinction coefficients, ε, and thermodynamic functions of formation, ΔH0, ΔG0, and ΔS0 have been determined. It was found that the data fit satisfactorily the 1:1 stoichiometric equilibrium: D + I2 = DI2 "outer complex". The EDA complexes obtained are of "n–σ*" type in which the nitrogen atom of thiazole is the donor center. Moreover, the effect of solvents on the K values is discussed in terms of the solute–solute and solute–solvent competing equilibria.

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36

Muro, Andrés F., Anil K. Chauhan, Srecko Gajovic, Alessandra Iaconcig, Fabiola Porro, Giorgio Stanta e Francisco E. Baralle. "Regulated splicing of the fibronectin EDA exon is essential for proper skin wound healing and normal lifespan". Journal of Cell Biology 162, n. 1 (7 luglio 2003): 149–60. http://dx.doi.org/10.1083/jcb.200212079.

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Abstract (sommario):

Fibronectins (FNs) are multifunctional high molecular weight glycoproteins present in the blood plasma and in the ECMs of tissues. The FN primary transcript undergoes alternative splicing in three regions generating up to 20 main different variants in humans. However, the precise role of the FN isoforms is poorly understood. One of the alternatively spliced exons is the extra domain A (EDA) or extra type III homology that is regulated spatially and temporally during development and aging. To study its in vivo function, we generated mice devoid of EDA exon-regulated splicing. Constitutive exon inclusion was obtained by optimizing the splice sites, whereas complete exclusion was obtained after in vivo CRE-loxP–mediated deletion of the exon. Homozygous mouse strains with complete exclusion or inclusion of the EDA exon were viable and developed normally, indicating that the alternative splicing at the EDA exon is not necessary during embryonic development. Conversely, mice without the EDA exon in the FN protein displayed abnormal skin wound healing, whereas mice having constitutive inclusion of the EDA exon showed a major decrease in the FN levels in all tissues. Moreover, both mutant mouse strains have a significantly shorter lifespan than the control mice, suggesting that EDA splicing regulation is necessary for efficient long-term maintenance of biological functions.

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37

Gholamreza Ghane Shalmani, Reza Ghiasi e Azam Marjani. "EDA, CDA and QTAIM Investigations in the (para-C5H4X) Ir(PH3)3 Iridabenzene Complexes". Russian Journal of Physical Chemistry B 15, S1 (agosto 2021): S6—S13. http://dx.doi.org/10.1134/s1990793121090141.

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38

Lima, Carolina G. S., Thiago de M. Lima, Marcelo Duarte, Igor D. Jurberg e Márcio W. Paixão. "Organic Synthesis Enabled by Light-Irradiation of EDA Complexes: Theoretical Background and Synthetic Applications". ACS Catalysis 6, n. 3 (28 gennaio 2016): 1389–407. http://dx.doi.org/10.1021/acscatal.5b02386.

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39

Weissflog, W., G. Pelzi e D. Demus. "EDA Complexes in Liquid Crystalline Mixed Phases of Novel Compounds with Lateral Dicyanoethenyl Substituents". Crystal Research and Technology 21, n. 1 (gennaio 1986): 117–21. http://dx.doi.org/10.1002/crat.2170210128.

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40

Lochhead, Marina R., Alexandra D. Brown, Alyssa C. Kirlin, Seth Chitayat, Kim Munro, Jane E. Findlay, George S. Baillie, David P. LeBrun, David N. Langelaan e Steven P. Smith. "Structural insights into TAZ2 domain–mediated CBP/p300 recruitment by transactivation domain 1 of the lymphopoietic transcription factor E2A". Journal of Biological Chemistry 295, n. 13 (25 febbraio 2020): 4303–15. http://dx.doi.org/10.1074/jbc.ra119.011078.

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Abstract (sommario):

The E-protein transcription factors guide immune cell differentiation, with E12 and E47 (hereafter called E2A) being essential for B-cell specification and maturation. E2A and the oncogenic chimera E2A-PBX1 contain three transactivation domains (ADs), with AD1 and AD2 having redundant, independent, and cooperative functions in a cell-dependent manner. AD1 and AD2 both mediate their functions by binding to the KIX domain of the histone acetyltransferase paralogues CREB-binding protein (CBP) and E1A-binding protein P300 (p300). This interaction is necessary for B-cell maturation and oncogenesis by E2A-PBX1 and occurs through conserved ΦXXΦΦ motifs (with Φ denoting a hydrophobic amino acid) in AD1 and AD2. However, disruption of this interaction via mutation of the KIX domain in CBP/p300 does not completely abrogate binding of E2A and E2A-PBX1. Here, we determined that E2A-AD1 and E2A-AD2 also interact with the TAZ2 domain of CBP/p300. Characterization of the TAZ2:E2A-AD1(1–37) complex indicated that E2A-AD1 adopts an α-helical structure and uses its ΦXXΦΦ motif to bind TAZ2. Whereas this region overlapped with the KIX recognition region, key KIX-interacting E2A-AD1 residues were exposed, suggesting that E2A-AD1 could simultaneously bind both the KIX and TAZ2 domains. However, we did not detect a ternary complex involving E2A-AD1, KIX, and TAZ2 and found that E2A containing both intact AD1 and AD2 is required to bind to CBP/p300. Our findings highlight the structural plasticity and promiscuity of E2A-AD1 and suggest that E2A binds both the TAZ2 and KIX domains of CBP/p300 through AD1 and AD2.

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41

Yang, Hong-qiang. "Application of EDA technology in intelligent communication electronic circuit". Journal of Electronic Research and Application 7, n. 5 (27 settembre 2023): 10–15. http://dx.doi.org/10.26689/jera.v7i5.5308.

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Abstract (sommario):

Abstract: Electronic design automation (EDA) technology is the product of the computer age and finds its foundation in CAD, CAM, CAT, and CAE. EDA is a kind of auxiliary tool in the design process, which requires the designer to carry out the file design work using hardware language as the foundation. Subsequently, the computer system automatically compiles and integrates the file to achieve simulation goals, and can complete the programming download of the target chip. At present, this technology is widely used in the communication of electronic circuits. This paper summarizes EDA technology and analyzes its specific application in communication electronic circuits, aiming at promoting the application of CDA technology and promoting the further development of the communication field.

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42

Anunziata, Jorge D., Norma S. Galaverna, Joaquín O. Singh e Juana J. Silber. "n-π Electron donor–acceptor complexes. III. Aliphatic amines with dicyanobenzenes. Electric and steric effects of the N-substituents on complex formation". Canadian Journal of Chemistry 64, n. 8 (1 agosto 1986): 1491–95. http://dx.doi.org/10.1139/v86-245.

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Abstract (sommario):

The interaction of several aliphatic amines as n-donors with 1,2-, 1,3-, and 1,4-dicyanobenzenes as π acceptors in n-hexane has been studied. The spectroscopic behaviour of the mixtures leads us to propose that Electron Donor – Acceptor (EDA) complexes are formed. Correlations of the experimental data with the amine structure were performed for the amine–1,4-dicyanobenzene complexes. By means of free energy related substituents and regression analysis, the electronic and steric effects of three N-substituents were quantitatively separated. Thus, with K representing the stability constants of the complexes, the values of log K are correlated with Taft's polar substituent constants, σ*, and Hancock's corrected steric substituent constants, [Formula: see text] The results allowed the proposal of a probable structure of the complex, at least with respect to the donor orientation.

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43

Werner, Bert, e Bernhard Neumüller. "[(TM EDA)2Li4Cl4(H2O)2]·2 TMEDA: stabförmige vierkernige Li-Komplexe verknüpft durch TMEDA / [(TM EDA)2Li4Cl4(H2O)2]·2 TMEDA: Stick-Like Tetranuclear Li Complexes Connected by TMEDA". Zeitschrift für Naturforschung B 50, n. 9 (1 settembre 1995): 1348–52. http://dx.doi.org/10.1515/znb-1995-0909.

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Abstract (sommario):

AbstractThe title compound 1 was synthesized by the reaction of LiCl with TM EDA (N,N,N′,N′- tetramethylethylendiamine) and water at 120 °C in boiling TM EDA. 1 was crystallized at - 30 °C as colorless crystals and characterized by NMR and IR spectroscopy as well as by an X-ray structure determination. 1 is a polymer in the solid state, built up by an alternating arrangement of stick-like tetranuclear Li complexes and two TMEDA molecules. The complexes and the TMEDA molecules are connected by hydrogen bridges in infinite chains.

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44

Visnovcova, Zuzana, Lucia Bona Olexova, Nikola Sekaninova, Igor Ondrejka, Igor Hrtanek, Dana Cesnekova, Simona Kelcikova, Ivan Farsky e Ingrid Tonhajzerova. "Spectral and Nonlinear Analysis of Electrodermal Activity in Adolescent Anorexia Nervosa". Applied Sciences 10, n. 13 (29 giugno 2020): 4514. http://dx.doi.org/10.3390/app10134514.

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Abstract (sommario):

Anorexia nervosa (AN) is an eating disorder with increasing prevalence in childhood and adolescence. Sympathetic dysregulation is supposed to be the underlying mechanism of increased cardiovascular risk in AN. Thus, we assess the electrodermal activity (EDA) as a non-invasive index of sympathetic cholinergic activity using linear and nonlinear analysis in adolescent AN with the aim of detecting potential biomarkers for AN-linked cardiovascular risk. We examined 25 adolescent girls with AN and 25 age-matched controls. EDA was continuously recorded during a 5-min resting phase. Evaluated parameters were: time-domain (skin conductance level, non-specific skin conductance responses), frequency-domain (EDA in very low, low, sympathetic, high and very high frequency bands) and nonlinear (approximate, sample, symbolic information entropies, detrended fluctuation analysis (DFA)) parameters of EDA and peripheral skin temperature. Our findings revealed lower EDA values indicating a decrease in the sympathetic nervous activity in female adolescents with the acute phase of AN. Further, we found higher nonlinear index DFA in AN vs. controls. We assumed that nonlinear index DFA could provide novel and independent information on the complex sympathetic regulatory network. We conclude that the parameters of complex EDA analysis could be used as sensitive biomarkers for the assessment of sympathetic cholinergic dysregulation as a risk factor for AN-linked cardiovascular morbidity.

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45

Tian, Zeyu. "Introduction to machine leaning in electronic design automation (EDA)". Applied and Computational Engineering 6, n. 1 (14 giugno 2023): 520–26. http://dx.doi.org/10.54254/2755-2721/6/20230849.

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Abstract (sommario):

The rapid growth of the intergraded circuit industry as predicted by Moores law has significantly increased the importance of efficient design processes. In addition, due to physical constraint, we will soon reach the limit of how small the size of the transistor can become, and the design processes will become more complex than ever. In order to cope with those challenges and introduce the product to the market within the time to market, the industry has been developing ways to apply machine learning to concurrent EDA tools. This paper will aim to introduce how machine learning is applied to varies processes of electronic design and how they improve the current EDA tools. We will also show the limitations and opportunities of ML based EDA tools and provide a rough idea of the potential future to those who are looking into this area.

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46

Fattaey, A. R., E. Harlow e K. Helin. "Independent regions of adenovirus E1A are required for binding to and dissociation of E2F-protein complexes". Molecular and Cellular Biology 13, n. 12 (dicembre 1993): 7267–77. http://dx.doi.org/10.1128/mcb.13.12.7267-7277.1993.

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Abstract (sommario):

The transcription factor E2F is present in independent complexes with the product of the retinoblastoma susceptibility gene, pRB, and a related gene product, p107, in association with the cyclin A-cdk2 or the cyclin E-cdk2 kinase complex. pRB and p107 can negatively regulate E2F activity, since overexpression of pRB or p107 in cells lacking a functional pRB leads to the repression of E2F activity. The products of the adenovirus E1A gene can disrupt E2F complexes and result in free and presumably active E2F transcription factor. The regions of E1A required for this function are also essential for binding to a number of cellular proteins, including pRB and p107. Through the use of a number of glutathione S-transferase fusion proteins representing different regions of E1A, as well as in vivo expression of E1A proteins containing deletions of either conserved region 1 (CR1) or CR2, we find that CR2 of E1A can form stable complexes with E2F. E1A proteins containing both CR1 and CR2 also associate with E2F, although the presence of these proteins results in the release of free E2F from its complexes. In vitro reconstitution experiments indicate that E1A-E2F interactions are not direct and that pRB can serve to facilitate these interactions. Complexes containing E1A, p107, cyclin A, and E2F were identified in vivo, which indicates that E1A may associate with E2F through either p107 or pRB. Peptide competition experiments demonstrate that the pRB-binding domain of the human E2F-1 protein can compete with the CR1 but not CR2 domain of E1A for binding to pRB. These results indicate that E1A CR1 and E2F-1 may bind to the same or overlapping sites on pRB and that E1A CR2 binds to an independent region. On the basis of our results, we propose a two-step model for the release of E2F from pRB and p107 cellular proteins.

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47

Fattaey, A. R., E. Harlow e K. Helin. "Independent regions of adenovirus E1A are required for binding to and dissociation of E2F-protein complexes." Molecular and Cellular Biology 13, n. 12 (dicembre 1993): 7267–77. http://dx.doi.org/10.1128/mcb.13.12.7267.

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Abstract (sommario):

The transcription factor E2F is present in independent complexes with the product of the retinoblastoma susceptibility gene, pRB, and a related gene product, p107, in association with the cyclin A-cdk2 or the cyclin E-cdk2 kinase complex. pRB and p107 can negatively regulate E2F activity, since overexpression of pRB or p107 in cells lacking a functional pRB leads to the repression of E2F activity. The products of the adenovirus E1A gene can disrupt E2F complexes and result in free and presumably active E2F transcription factor. The regions of E1A required for this function are also essential for binding to a number of cellular proteins, including pRB and p107. Through the use of a number of glutathione S-transferase fusion proteins representing different regions of E1A, as well as in vivo expression of E1A proteins containing deletions of either conserved region 1 (CR1) or CR2, we find that CR2 of E1A can form stable complexes with E2F. E1A proteins containing both CR1 and CR2 also associate with E2F, although the presence of these proteins results in the release of free E2F from its complexes. In vitro reconstitution experiments indicate that E1A-E2F interactions are not direct and that pRB can serve to facilitate these interactions. Complexes containing E1A, p107, cyclin A, and E2F were identified in vivo, which indicates that E1A may associate with E2F through either p107 or pRB. Peptide competition experiments demonstrate that the pRB-binding domain of the human E2F-1 protein can compete with the CR1 but not CR2 domain of E1A for binding to pRB. These results indicate that E1A CR1 and E2F-1 may bind to the same or overlapping sites on pRB and that E1A CR2 binds to an independent region. On the basis of our results, we propose a two-step model for the release of E2F from pRB and p107 cellular proteins.

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48

Murray, Elizabeth L., e Tyrrell Conway. "Multiple Regulators Control Expression of the Entner-Doudoroff Aldolase (Eda) of Escherichia coli". Journal of Bacteriology 187, n. 3 (1 febbraio 2005): 991–1000. http://dx.doi.org/10.1128/jb.187.3.991-1000.2005.

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ABSTRACT The Escherichia coli eda gene, which encodes the Entner-Doudoroff aldolase, is central to the catabolism of several sugar acids. Here, we show that Eda synthesis is induced by growth on gluconate, glucuronate, or methyl-β-d-glucuronide; phosphate limitation; and carbon starvation. Transcription of eda initiates from three promoters, designated P1, P2, and P4, each of which is responsible for induction under different growth conditions. P1 controls eda induction on gluconate and is regulated by GntR. P2 controls eda induction on glucuronate and galacturonate and is regulated by KdgR. P4 is active under conditions of phosphate starvation and is directly controlled by PhoB. In addition, CsrA activates Eda synthesis, apparently by an indirect mechanism that may be involved in the modest changes in expression level that are associated with carbon starvation. The complex regulation of eda is discussed with respect to its several physiological roles, which apparently accommodate not only sugar acid catabolism but also detoxification of metabolites that could accumulate during starvation-induced stress.

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Musselman, Bradley W., e Nicolai Lehnert. "Bridging and axial carbene binding modes in cobalt corrole complexes: effect on carbene transfer". Chemical Communications 56, n. 94 (2020): 14881–84. http://dx.doi.org/10.1039/d0cc07073d.

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50

Lee, Cherylyn, e H. K. Hall. "Photocopolymerizations of electron-rich olefins with electron-poor olefins by irradiation of their EDA complexes". Macromolecules 22, n. 1 (gennaio 1989): 21–25. http://dx.doi.org/10.1021/ma00191a004.

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