Articoli di riviste: "DDAI"

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Ragazzone, Pasqualina. "L'approccio ericksoniano nel trattamento del DDAI". IPNOSI, n. 2 (maggio 2012): 39–54. http://dx.doi.org/10.3280/ipn2011-002003.

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Questo articolo intende evidenziare il complesso meccanismo di strutturazione del disturbo da deficit di attenzione/iperattivitŕ, noto con l'acronimo italiano DDAI, e come fronteggiarlo. Durante la sua esperienza ad un Centro di Neuropsichiatria Infantile l'autrice conosce S., un bambino di nove anni con diagnosi di DDAI. S. sembra non trovare un modo per trattenersi dal reagire in modo impulsivo e aggressivo, č un bambino che tutti allontanano perché scappa, corre, non riesce a stare seduto, č assediato dagli sguardi di dissenso degli insegnanti e dei genitori e dai commenti dei compagni di classe. Non riesce a controllare la rabbia, fino al punto di sentirsi come una bomba pronta ad esplodere da un momento all'altro. Come aiutare un bambino con queste problematiche? La risposta che l'autrice ha trovato a questo interrogativo viene dalla sua formazione, da ciň che la teoria di Milton Erickson ha insegnato: guardare le risorse del paziente, e non i suoi limiti, utilizzare tutto ciň che il paziente porta, stabilire con lui una buona alleanza terapeutica. In questo articolo vengo- no dapprima analizzate le caratteristiche primarie e secondarie del disturbo, l'eziologia e l'epidemiologia e successivamente vengono presentati i diversi tipi di approccio terapeutico al DDAI. Infine sono riportati la storia clinica del piccolo S. e i colloqui effettuati con lui.

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Russo, Federica, Emiliana Stendardo e Carlo Buonanno. "L'impulsività nel disturbo da deficit di attenzione e iperattività (DDAI) e nel disturbo da uso di sostanze (DUS)". QUADERNI DI PSICOTERAPIA COGNITIVA, n. 41 (dicembre 2017): 35–51. http://dx.doi.org/10.3280/qpc2017-041003.

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Galambos, Jörg, Claudia Meuli-Simmen, Regula Schmid, Lisa S. Steinmann e Werner Kempf. "Diffuse Dermal Angiomatosis of the Breast: A Distinct Entity in the Spectrum of Cutaneous Reactive Angiomatoses – Clinicopathologic Study of Two Cases and Comprehensive Review of the Literature". Case Reports in Dermatology 9, n. 3 (13 ottobre 2017): 194–205. http://dx.doi.org/10.1159/000480721.

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Diffuse dermal angiomatosis (DDA) is a rare reactive angioproliferation in the skin and considered to be a subtype in the group of cutaneous reactive angiomatoses. DDA is clinically characterized by livedoid patches and plaques with tender ulceration. Its histologic features are a reactive diffuse proliferation of bland endothelial cells and pericytes within the dermis, forming small capillary vessels. Previously described cases of DDA most commonly involved the limbs and were associated with a wide spectrum of predisposing comorbidities, especially advanced atherosclerotic vascular disease and arteriovenous fistula. However, several cases of DDA of the breast (DDAB) have been reported in recent years. In this study we present 2 additional patients with DDAB and review all 36 cases of DDAB published in the literature. We describe the clinical and histopathologic characteristics, hypothesized pathogenetic mechanisms, and predisposing conditions of this rare skin disorder and discuss treatment options. The breast is a more commonly involved site of DDA than previously believed. DDAB typically occurs in middle-aged women and is associated with macromastia, overweight or obesity, and probably smoking. Predisposing comorbid conditions differ from those of DDA involving other parts of the body, making DDAB a unique clinicopathologic entity in the spectrum of cutaneous reactive angiomatoses. Currently there is no consensus on the best therapeutic approach. Isotretinoin and other medical therapies have been used with limited success. Breast reduction surgery appears to be a viable treatment option for DDAB in women with macromastia and might provide definitive healing.

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Jensen, Jannik, e Dan Kristiansen. "DDI 3 Development at DDA". IASSIST Quarterly 33, n. 1 (11 novembre 2010): 31. http://dx.doi.org/10.29173/iq648.

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Lai, Po-Ting, Wei-Liang Lu, Ting-Rung Kuo, Chia-Ru Chung, Jen-Chieh Han, Richard Tzong-Han Tsai e Jorng-Tzong Horng. "Using a Large Margin Context-Aware Convolutional Neural Network to Automatically Extract Disease-Disease Association from Literature: Comparative Analytic Study". JMIR Medical Informatics 7, n. 4 (26 novembre 2019): e14502. http://dx.doi.org/10.2196/14502.

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Background Research on disease-disease association (DDA), like comorbidity and complication, provides important insights into disease treatment and drug discovery, and a large body of the literature has been published in the field. However, using current search tools, it is not easy for researchers to retrieve information on the latest DDA findings. First, comorbidity and complication keywords pull up large numbers of PubMed studies. Second, disease is not highlighted in search results. Finally, DDA is not identified, as currently no disease-disease association extraction (DDAE) dataset or tools are available. Objective As there are no available DDAE datasets or tools, this study aimed to develop (1) a DDAE dataset and (2) a neural network model for extracting DDA from the literature. Methods In this study, we formulated DDAE as a supervised machine learning classification problem. To develop the system, we first built a DDAE dataset. We then employed two machine learning models, support vector machine and convolutional neural network, to extract DDA. Furthermore, we evaluated the effect of using the output layer as features of the support vector machine-based model. Finally, we implemented large margin context-aware convolutional neural network architecture to integrate context features and convolutional neural networks through the large margin function. Results Our DDAE dataset consisted of 521 PubMed abstracts. Experiment results showed that the support vector machine-based approach achieved an F1 measure of 80.32%, which is higher than the convolutional neural network-based approach (73.32%). Using the output layer of convolutional neural network as a feature for the support vector machine does not further improve the performance of support vector machine. However, our large margin context-aware-convolutional neural network achieved the highest F1 measure of 84.18% and demonstrated that combining the hinge loss function of support vector machine with a convolutional neural network into a single neural network architecture outperforms other approaches. Conclusions To facilitate the development of text-mining research for DDAE, we developed the first publicly available DDAE dataset consisting of disease mentions, Medical Subject Heading IDs, and relation annotations. We developed different conventional machine learning models and neural network architectures and evaluated their effects on our DDAE dataset. To further improve DDAE performance, we propose an large margin context-aware-convolutional neural network model for DDAE that outperforms other approaches.

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Stukel, M. R., V. J. Coles, M. T. Brooks e R. R. Hood. "Top-down, bottom-up and physical controls on diatom-diazotroph assemblage growth in the Amazon River plume". Biogeosciences 11, n. 12 (19 giugno 2014): 3259–78. http://dx.doi.org/10.5194/bg-11-3259-2014.

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Abstract. The nutrient-rich waters of the Amazon River plume (ARP) support dense blooms of diatom-diazotroph assemblages (DDAs) that introduce large quantities of new nitrogen to the planktonic ecosystem and, unlike other nitrogen-fixers, are likely to directly fuel vertical carbon flux. To investigate the factors controlling DDA blooms, we develop a five phytoplankton (cyanobacteria, diatoms, unicellular microbial diazotrophs, DDAs, and Trichodesmium), two zooplankton model and embed it within a 1/6° resolution physical model of the tropical and subtropical Atlantic. The model generates realistic DDA blooms in the ARP and also exhibits basin-wide primary production, nitrogen fixation, and grazing rates consistent with observed values. By following ARP water parcels with synthetic Lagrangian drifters released at the river mouth we are able to assess the relative impacts of grazing, nutrient supply, and physical forcing on DDA bloom formation. DDA bloom formation is stimulated in the nitrogen-poor and silica-rich water of the ARP by decreases in grazing pressure when mesozooplankton (which co-occur in high densities with coastal diatom blooms) concentrations decrease. Bloom termination is driven primarily by silica limitation of the DDAs. In agreement with in situ data, this net growth niche for DDAs exists in a salinity range from ∼20–34 PSU, although this co-occurrence is coincidental rather than causative. Because net growth rates are relatively modest, bloom formation in ARP water parcels depends critically on the time spent in this ideal habitat, with high DDA biomass only occurring when water parcels spent >23 days in the optimal habitat niche.

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Le Saint, Cecile, Raphael Terreux, Daniele Duval, Jacques Durant, Helene Ettesse, Pierre Dellamonica, Roger Guedj, Jean Pierre Vincent e Anny Cupo. "Determination of ddATP Levels in Human Immunodeficiency Virus-Infected Patients Treated with Dideoxyinosine". Antimicrobial Agents and Chemotherapy 48, n. 2 (febbraio 2004): 589–95. http://dx.doi.org/10.1128/aac.48.2.589-595.2004.

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ABSTRACT Clinical failures of the highly active antiretroviral therapy could result from inefficient intracellular concentrations of antiviral drugs. The determination of drug contents in target cells of each patient would be useful in clinical investigations and trials. The purpose of this work was to quantify the intracellular concentration of ddATP, the active metabolite of dideoxyinosine (ddI), in peripheral blood mononuclear cells (PBMCs) of human immunodeficiency virus (HIV)-infected patients treated with ddI. We have raised antibodies against ddA-citrate, a stable isostere of ddATP selected on the basis of its structural and electronic analogies with ddATP. The anti-ddA-citrate antibodies recognized ddATP and ddA with nanomolar affinities and cross-reacted neither with any of the nucleotide reverse transcriptase inhibitors used in HIV therapy nor with their phosphorylated metabolites. The three phosphorylated metabolites of ddI (ddAMP, ddADP, and ddATP) were purified by anion exchange chromatography and the amount of each metabolite was determined by radioimmunoassay with or without prior phosphatase treatment. The intracellular levels of the three ddI metabolites were measured both in an in vitro model and in PBMCs of HIV-infected patients under ddI treatment. The possibility to measure intracellular levels of ddATP from small blood samples of HIV-infected patients treated with ddI could be exploited to develop individual therapeutic monitoring.

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Bahar, Muh Akbar, Pauline Lanting, Jens H. J. Bos, Rolf H. Sijmons, Eelko Hak e Bob Wilffert. "Impact of Drug-Gene-Interaction, Drug-Drug-Interaction, and Drug-Drug-Gene-Interaction on (es)Citalopram Therapy: The PharmLines Initiative". Journal of Personalized Medicine 10, n. 4 (28 novembre 2020): 256. http://dx.doi.org/10.3390/jpm10040256.

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We explored the association between CYP2C19/3A4 mediated drug-gene-interaction (DGI), drug-drug-interaction (DDI) and drug-drug-gene-interaction (DDGI) and (es)citalopram dispensing course. A cohort study was conducted among adult Caucasians from the Lifelines cohort (167,729 participants) and linked dispensing data from the IADB.nl database as part of the PharmLines Initiative. Exposure groups were categorized into (es)citalopram starters with DGI, DDI and DDGI. The primary outcome was drug switching and/or dose adjustment, and the secondary was early discontinuation after the start of (es)citalopram. Logistic regression modeling was applied to estimate adjusted odd ratios with their confidence interval. We identified 316 (es)citalopram starters with complete CYP2C19/3A4 genetic information. The CYP2C19 IM/PM and CYP3A4 NM combination increased risks of switching and/or dose reduction (OR: 2.75, 95% CI: 1.03–7.29). The higher effect size was achieved by the CYP2C19 IM/PM and CYP3A4 IM combination (OR: 4.38, 95% CI: 1.22–15.69). CYP2C19/3A4 mediated DDIs and DDGIs showed trends towards increased risks of switching and/or dose reduction. In conclusion, a DGI involving predicted decreased CYP2C19 function increases the need for (es)citalopram switching and/or dose reduction which might be enhanced by co-presence of predicted decreased CYP3A4 function. For DDI and DDGI, no conclusions can be drawn from the results.

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Wojciak-Stothard, Beata, Belen Torondel, Lan Zhao, Thomas Renné e James M. Leiper. "Modulation of Rac1 Activity by ADMA/DDAH Regulates Pulmonary Endothelial Barrier Function". Molecular Biology of the Cell 20, n. 1 (gennaio 2009): 33–42. http://dx.doi.org/10.1091/mbc.e08-04-0395.

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Endogenously produced nitric oxide synthase inhibitor, asymmetric methylarginine (ADMA) is associated with vascular dysfunction and endothelial leakage. We studied the role of ADMA, and the enzymes metabolizing it, dimethylarginine dimethylaminohydrolases (DDAH) in the regulation of endothelial barrier function in pulmonary macrovascular and microvascular cells in vitro and in lungs of genetically modified heterozygous DDAHI knockout mice in vivo. We show that ADMA increases pulmonary endothelial permeability in vitro and in in vivo and that this effect is mediated by nitric oxide (NO) acting via protein kinase G (PKG) and independent of reactive oxygen species formation. ADMA-induced remodeling of actin cytoskeleton and intercellular adherens junctions results from a decrease in PKG-mediated phosphorylation of vasodilator-stimulated phosphoprotein (VASP) and a subsequent down-regulation of Rac1 activity. The effects of ADMA on endothelial permeability, Rac1 activation and VASP phosphorylation are prevented by overexpression of active DDAHI and DDAHII, whereas inactive DDAH mutants have no effect. These findings demonstrate for the first time that ADMA metabolism critically determines pulmonary endothelial barrier function by modulating Rac1-mediated remodeling of the actin cytoskeleton and intercellular junctions.

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Pruvost, Alain, Eugènia Negredo, Henri Benech, Frédéric Theodoro, Jordi Puig, Eulàlia Grau, Elisabet García, José Moltó, Jacques Grassi e Bonaventura Clotet. "Measurement of Intracellular Didanosine and Tenofovir Phosphorylated Metabolites and Possible Interaction of the Two Drugs in Human Immunodeficiency Virus-Infected Patients". Antimicrobial Agents and Chemotherapy 49, n. 5 (maggio 2005): 1907–14. http://dx.doi.org/10.1128/aac.49.5.1907-1914.2005.

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ABSTRACT Recent work has demonstrated the existence of a systemic interaction between didanosine (ddI) and tenofovir disoproxyl fumarate (TDF) that leads to a significant increase in plasma ddI levels when coadministered with TDF (40 to 50% increase). These two drugs are, respectively, nucleoside and nucleotide analogues of adenosine and efficiently inhibit the human immunodeficiency virus (HIV) reverse transcriptase when transformed to their triphosphate moieties in the intracellular (IC) medium (ddA-TP and TFV-DP, respectively). Since ddI and TDF partly share the same IC metabolic pathway leading to the active triphosphates, we investigated a putative IC interaction. We used high-performance liquid chromatography-tandem mass spectrometry techniques to determine ddA-TP and TFV-DP IC levels in HIV-infected patients cotreated with both drugs, in comparison with patients treated with just one of the two drugs. These measurements revealed no significant differences in IC levels of the corresponding triphosphates when ddI (250 mg, once a day [QD]) was coadministered with TDF (300 mg, QD) compared to ddI 400 mg (QD) administered without TDF, thus supporting the dose adaptation proposed for this combination. However, we observed that both ddA-TP and TFV-DP have very long IC half-lives, resulting in unusual IC pharmacokinetic profiles with no significant changes in triphosphate concentrations between two dosings. In the case of TFV-DP, this t 1/2 of elimination was roughly estimated to be 180 h (7.5 days). This characteristic is certainly interesting in terms of efficacy but could have some drawbacks in terms of virus resistance for patients discontinuing these drugs.

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Suratanee, Apichat, e Kitiporn Plaimas. "DDA: A Novel Network-Based Scoring Method to Identify Disease-Disease Associations". Bioinformatics and Biology Insights 9 (gennaio 2015): BBI.S35237. http://dx.doi.org/10.4137/bbi.s35237.

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Categorizing human diseases provides higher efficiency and accuracy for disease diagnosis, prognosis, and treatment. Disease-disease association (DDA) is a precious information that indicates the large-scale structure of complex relationships of diseases. However, the number of known and reliable associations is very small. Therefore, identification of DDAs is a challenging task in systems biology and medicine. Here, we developed a novel network-based scoring algorithm called DDA to identify the relationships between diseases in a large-scale study. Our method is developed based on a random walk prioritization in a protein-protein interaction network. This approach considers not only whether two diseases directly share associated genes but also the statistical relationships between two different diseases using known disease-related genes. Predicted associations were validated by known DDAs from a database and literature supports. The method yielded a good performance with an area under the curve of 71% and outperformed other standard association indices. Furthermore, novel DDAs and relationships among diseases from the clusters analysis were reported. This method is efficient to identify disease-disease relationships on an interaction network and can also be generalized to other association studies to further enhance knowledge in medical studies.

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Konopelchenko, B. G. "On the Deformation Theory of Structure Constants for Associative Algebras". Advances in Mathematical Physics 2010 (2010): 1–21. http://dx.doi.org/10.1155/2010/389091.

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An algebraic scheme for constructing deformations of structure constants for associative algebras generated by deformation driving algebras (DDAs) is discussed. An ideal of left divisors of zero plays a central role in this construction. Deformations of associative three-dimensional algebras with the DDA being a three-dimensional Lie algebra and their connection with integrable systems are studied.

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Zhang, Min, Chong-sheng Peng e Xiao-bo Li. "In VivoandIn VitroMetabolites from the Main Diester and Monoester Diterpenoid Alkaloids in a Traditional Chinese Herb, theAconitumSpecies". Evidence-Based Complementary and Alternative Medicine 2015 (2015): 1–23. http://dx.doi.org/10.1155/2015/252434.

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Diester diterpenoid alkaloids (DDAs), such as aconitine (AC), mesaconitine (MA), and hypaconitine (HA), are both pharmacologically active compounds and toxic ingredients in a traditional Chinese herb, theAconitumspecies. Many DDA metabolism studies have been performed to explore mechanisms for reducing toxicity in these compounds and inAconitumspecies extracts for safe clinical administration. In this review, we summarize recent progress on the metabolism of toxic AC, MA, and HA and corresponding monoester diterpenoid alkaloids (MDAs) in the gastrointestinal tract and liver in different animal species and humansin vivoand/orin vitro, where these alkaloids are primarily metabolized by cytochrome P450 enzymes, carboxylesterases, and intestinal bacteria, which produces phase I metabolites, ester hydrolysed products, and lipoalkaloids. Furthermore, we classify metabolites detected in the blood and urine, where the aforementioned metabolites are absorbed and excreted. Less toxic MDAs and nontoxic alcohol amines are the primary DDA metabolites detected in the blood. Most other DDAs metabolites produced in the intestine and liver detected in the urine have not been reported in the blood. We propose an explanation for this nonconformity. Finally, taking AC, for instance, we generalize a process of toxicity reduction in the body after oral AC administration for the first time.

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Psathas, Emmanouil D., Athanasios Katsargyris, Stella Lioudaki, Demetrios N. Moris, Mikes Doulaptsis e Chris Klonaris. "Treatment paradigms for ductus arteriosus aneurysms in adults". Vascular 22, n. 4 (2 luglio 2013): 297–301. http://dx.doi.org/10.1177/1708538113495680.

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We report two symptomatic cases of ductus arteriosus aneurysm (DDA) in adults treated in our department over a 5-years period. One patient underwent an open off-pump surgical procedure, while the second one was treated with partial aortic arch debranching and endovascular stent-grafting. DDA in adults is an uncommon condition and can present with rupture, hoarseness or symptoms of airway obstruction. Although indications for intervention are not clearly established, most authors advocate that DDAs should be treated regardless of their size, to avoid the risk of rupture, while others reserve intervention for symptomatic patients. We report on the management of these patients and provide an updated review of the current literature.

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Marok, Fatima Zahra, Laura Maria Fuhr, Nina Hanke, Dominik Selzer e Thorsten Lehr. "Physiologically Based Pharmacokinetic Modeling of Bupropion and Its Metabolites in a CYP2B6 Drug-Drug-Gene Interaction Network". Pharmaceutics 13, n. 3 (4 marzo 2021): 331. http://dx.doi.org/10.3390/pharmaceutics13030331.

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The noradrenaline and dopamine reuptake inhibitor bupropion is metabolized by CYP2B6 and recommended by the FDA as the only sensitive substrate for clinical CYP2B6 drug–drug interaction (DDI) studies. The aim of this study was to build a whole-body physiologically based pharmacokinetic (PBPK) model of bupropion including its DDI-relevant metabolites, and to qualify the model using clinical drug–gene interaction (DGI) and DDI data. The model was built in PK-Sim® applying clinical data of 67 studies. It incorporates CYP2B6-mediated hydroxylation of bupropion, metabolism via CYP2C19 and 11β-HSD, as well as binding to pharmacological targets. The impact of CYP2B6 polymorphisms is described for normal, poor, intermediate, and rapid metabolizers, with various allele combinations of the genetic variants CYP2B6*1, *4, *5 and *6. DDI model performance was evaluated by prediction of clinical studies with rifampicin (CYP2B6 and CYP2C19 inducer), fluvoxamine (CYP2C19 inhibitor) and voriconazole (CYP2B6 and CYP2C19 inhibitor). Model performance quantification showed 20/20 DGI ratios of hydroxybupropion to bupropion AUC ratios (DGI AUCHBup/Bup ratios), 12/13 DDI AUCHBup/Bup ratios, and 7/7 DDGI AUCHBup/Bup ratios within 2-fold of observed values. The developed model is freely available in the Open Systems Pharmacology model repository.

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Poruchynsky, Marianne S., Edina Komlodi-Pasztor, Shana Trostel, Julia Wilkerson, Marie Regairaz, Yves Pommier, Xu Zhang et al. "Microtubule-targeting agents augment the toxicity of DNA-damaging agents by disrupting intracellular trafficking of DNA repair proteins". Proceedings of the National Academy of Sciences 112, n. 5 (20 gennaio 2015): 1571–76. http://dx.doi.org/10.1073/pnas.1416418112.

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The paradigm that microtubule-targeting agents (MTAs) cause cell death via mitotic arrest applies to rapidly dividing cells but cannot explain MTA activity in slowly growing human cancers. Many preferred cancer regimens combine a MTA with a DNA-damaging agent (DDA). We hypothesized that MTAs synergize with DDAs by interfering with trafficking of DNA repair proteins on interphase microtubules. We investigated nine proteins involved in DNA repair: ATM, ATR, DNA-PK, Rad50, Mre11, p95/NBS1, p53, 53BP1, and p63. The proteins were sequestered in the cytoplasm by vincristine and paclitaxel but not by an aurora kinase inhibitor, colocalized with tubulin by confocal microscopy and coimmunoprecipitated with the microtubule motor dynein. Furthermore, adding MTAs to radiation, doxorubicin, or etoposide led to more sustained γ-H2AX levels. We conclude DNA damage-repair proteins traffic on microtubules and addition of MTAs sequesters them in the cytoplasm, explaining why MTA/DDA combinations are common anticancer regimens.

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Hollenhorst, Marie A., Jon Clardy e Christopher T. Walsh. "The ATP-Dependent Amide Ligases DdaG and DdaF Assemble the Fumaramoyl-Dipeptide Scaffold of the Dapdiamide Antibiotics". Biochemistry 48, n. 43 (3 novembre 2009): 10467–72. http://dx.doi.org/10.1021/bi9013165.

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Hollenhorst, Marie A., Jon Clardy e Christopher T. Walsh. "The ATP-Dependent Amide Ligases DdaG and DdaF Assemble the Fumaramoyl-Dipeptide Scaffold of the Dapdiamide Antibiotics". Biochemistry 49, n. 29 (27 luglio 2010): 6296. http://dx.doi.org/10.1021/bi101016e.

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Türk, Denise, Nina Hanke e Thorsten Lehr. "A Physiologically-Based Pharmacokinetic Model of Trimethoprim for MATE1, OCT1, OCT2, and CYP2C8 Drug–Drug–Gene Interaction Predictions". Pharmaceutics 12, n. 11 (10 novembre 2020): 1074. http://dx.doi.org/10.3390/pharmaceutics12111074.

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Trimethoprim is a frequently-prescribed antibiotic and therefore likely to be co-administered with other medications, but it is also a potent inhibitor of multidrug and toxin extrusion protein (MATE) and a weak inhibitor of cytochrome P450 (CYP) 2C8. The aim of this work was to develop a physiologically-based pharmacokinetic (PBPK) model of trimethoprim to investigate and predict its drug–drug interactions (DDIs). The model was developed in PK-Sim®, using a large number of clinical studies (66 plasma concentration–time profiles with 36 corresponding fractions excreted in urine) to describe the trimethoprim pharmacokinetics over the entire published dosing range (40 to 960 mg). The key features of the model include intestinal efflux via P-glycoprotein (P-gp), metabolism by CYP3A4, an unspecific hepatic clearance process, and a renal clearance consisting of glomerular filtration and tubular secretion. The DDI performance of this new model was demonstrated by prediction of DDIs and drug–drug–gene interactions (DDGIs) of trimethoprim with metformin, repaglinide, pioglitazone, and rifampicin, with all predicted DDI and DDGI AUClast and Cmax ratios within 1.5-fold of the clinically-observed values. The model will be freely available in the Open Systems Pharmacology model repository, to support DDI studies during drug development.

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Jabir, T., V. Dhanya, Y. Jesmi, M. P. Prabhakaran, N. Saravanane, G. V. M. Gupta e A. A. M. Hatha. "Occurrence and Distribution of a Diatom-Diazotrophic Cyanobacteria Association during a Trichodesmium Bloom in the Southeastern Arabian Sea". International Journal of Oceanography 2013 (6 agosto 2013): 1–6. http://dx.doi.org/10.1155/2013/350594.

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Symbiotic diatom-diazotrophic cyanobacteria association (DDA) of Rhizosolenia hebetata and Rhizosolenia formosa with endosymbiotic cyanobacteria Richelia intracellularis was noticed and documented for the first time during a bloom of the cyanobacterium Trichodesmium erythraeum in the oligotrophic shelf waters along Kochi and Mangalore transects, southeastern Arabian Sea (SEAS), during spring intermonsoon (April 2012). Although the host is frequently seen, the symbiont is rarely reported in the Indian EEZ. The presence of nitrogen-fixing symbiotic association of Rhizosolenia-Richelia along with Trichodesmium erythraeum highlights the significance of DDAs on the nutrient and energy budgets of phytoplankton in the oligotrophic environments of the Arabian Sea during spring intermonsoon.

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Bale, Nicole J., Tracy A. Villareal, Ellen C. Hopmans, Corina P. D. Brussaard, Marc Besseling, Denise Dorhout, Jaap S. Sinninghe Damsté e Stefan Schouten. "C<sub>5</sub> glycolipids of heterocystous cyanobacteria track symbiont abundance in the diatom <i>Hemiaulus hauckii</i> across the tropical North Atlantic". Biogeosciences 15, n. 4 (1 marzo 2018): 1229–41. http://dx.doi.org/10.5194/bg-15-1229-2018.

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Abstract. Diatom–diazotroph associations (DDAs) include marine heterocystous cyanobacteria found as exosymbionts and endosymbionts in multiple diatom species. Heterocysts are the site of N2 fixation and have thickened cell walls containing unique heterocyst glycolipids which maintain a low oxygen environment within the heterocyst. The endosymbiotic cyanobacterium Richelia intracellularis found in species of the diatom genus Hemiaulus and Rhizosolenia makes heterocyst glycolipids (HGs) which are composed of C30 and C32 diols and triols with pentose (C5) moieties that are distinct from limnetic cyanobacterial HGs with predominantly hexose (C6) moieties. Here we applied a method for analysis of intact polar lipids to the study of HGs in suspended particulate matter (SPM) and surface sediment from across the tropical North Atlantic. The study focused on the Amazon plume region, where DDAs are documented to form extensive surface blooms, in order to examine the utility of C5 HGs as markers for DDAs as well as their transportation to underlying sediments. C30 and C32 triols with C5 pentose moieties were detected in both marine SPM and surface sediments. We found a significant correlation between the water column concentration of these long-chain C5 HGs and DDA symbiont counts. In particular, the concentrations of both the C5 HGs (1-(O-ribose)-3,27,29-triacontanetriol (C5 HG30 triol) and 1-(O-ribose)-3,29,31-dotriacontanetriol (C5 HG32 triol)) in SPM exhibited a significant correlation with the number of Hemiaulus hauckii symbionts. This result strengthens the idea that long-chain C5 HGs can be applied as biomarkers for marine endosymbiotic heterocystous cyanobacteria. The presence of the same C5 HGs in surface sediment provides evidence that they are effectively transported to the sediment and hence have potential as biomarkers for studies of the contribution of DDAs to the paleo-marine N cycle.

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Uchiyama, Saburo, Kazumasa Isobe e Shin-Ichi Nagai. "Isozymes of ribonuclease and the changes in their relative levels during development in the cellular slime mould Dictyostelium discoideum". Biochemistry and Cell Biology 69, n. 1 (1 gennaio 1991): 84–87. http://dx.doi.org/10.1139/o91-012.

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The isozymes of ribonuclease were analyzed in cell-free, crude extracts of Dictyostelium discoideum by activity staining of polyacrylamide gels after electrophoresis. The relative levels of three isozymes were then examined during the growth and during the first stages of multicellular development. We observed the replacement of two of these three isozymes by two other isozymes at the pseudoplasmodial stage. These isozymes were different from ribonuclease T1 in terms of their mobility in polyacrylamide gels during electrophoresis. The mobilities of two of the isozymes, DdI and DdII, were 59 and 42% of that of ribonuclease T1. The changes in the relative levels of the isozymes during development are discussed.Key words: ribonuclease, isozyme, cellular slime mould, development, Dictyostelium discoideum.

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23

Potvin, Corey K., e Louis J. Wicker. "Comparison between Dual-Doppler and EnKF Storm-Scale Wind Analyses: Observing System Simulation Experiments with a Supercell Thunderstorm". Monthly Weather Review 140, n. 12 (1 dicembre 2012): 3972–91. http://dx.doi.org/10.1175/mwr-d-12-00044.1.

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Abstract Kinematical analyses of mobile radar observations are critical to advancing the understanding of supercell thunderstorms. Maximizing the accuracy of these and subsequent dynamical analyses, and appropriately characterizing the uncertainty in ensuing conclusions about storm structure and processes, requires thorough knowledge of the typical errors obtained using different retrieval techniques. This study adopts an observing system simulation experiment (OSSE) framework to explore the errors obtained from ensemble Kalman filter (EnKF) assimilation versus dual-Doppler analysis (DDA) of storm-scale mobile radar data. The radar characteristics and EnKF model errors are varied to explore a range of plausible scenarios. When dual-radar data are assimilated, the EnKF produces substantially better wind retrievals at higher altitudes, where DDAs are more sensitive to unaccounted flow evolution, and in data-sparse regions such as the storm inflow sector. Near the ground, however, the EnKF analyses are comparable to the DDAs when the radar cross-beam angles (CBAs) are poor, and slightly worse than the DDAs when the CBAs are optimal. In the single-radar case, the wind analyses benefit substantially from using finer grid spacing than in the dual-radar case for the objective analysis of radar observations. The analyses generally degrade when only single-radar data are assimilated, particularly when microphysical parameterization or low-level environmental wind errors are introduced. In some instances, this leads to large errors in low-level vorticity stretching and Lagrangian circulation calculations. Nevertheless, the results show that while multiradar observations of supercells are always preferable, judicious use of single-radar EnKF assimilation can yield useful analyses.

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24

Hollenhorst, Marie A., Jon Clardy e Christopher T. Walsh. "Correction to The ATP-Dependent Amide Ligases DdaG and DdaF Assemble the Fumaramoyl-Dipeptide Scaffold of the Dapdiamide Antibiotics". Biochemistry 49, n. 8 (2 marzo 2010): 1808. http://dx.doi.org/10.1021/bi100095k.

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25

Dantoni, Patrícia, Ana Clara B. Rodrigues, Margareth Mie N. Matsuda e Nina Coichev. "Effect of some surfactants on the chemiluminescent reactions of bis(2,4,6-trichlorophenyl)oxalate and bis(2-nitrophenyl)oxalate with hydrogen peroxide". Canadian Journal of Chemistry 90, n. 6 (giugno 2012): 534–41. http://dx.doi.org/10.1139/v2012-025.

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The chemiluminescent reactions of bis(2,4,6-trichlorophenyl)oxalate (TCPO) and bis(2-nitrophenyl)oxalate (2-NPO) with hydrogen peroxide in acetonitrile/water micellar systems (anionic, cationic, and non-ionic) and γ-cyclodextrin were studied in the presence of fluoranthene or 9,10-diphenylanthracene, imidazole, and two buffer solutions, HTRIS+/TRIS and H2PO4–/HPO42–. The relative chemiluminenscence (CL) intensity is higher in the presence of the cationic (DDAB, CTAC, DODAC, and OTAC), anionic (SDS), and non-ionic (Tween 80) surfactants. In the presence of some non-ionic surfactants (Brij 35, Brij 76, and Tween 20), the CL intensity was partially quenched compared with the reaction with no surfactant. The sensitivity for hydrogen peroxide determination in the range 0.01 × 10−4 to 1.0 × 10−4 mol L–1, considering the slope of the calibration curves (maximum peak height of CL vs. concentration), improved with the introduction of DDAH, CTAB, and SDS in HTRIS+/TRIS buffer.

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26

Secrist, John A., Robert M. Riggs, Robert N. Comber e John A. Montgomery. "Syntheses of Phosphonate Analogues of Dideoxyadenosine (DDA)-, Dideoxycytidine (DDC)-, Dideoxyinosine (DDI)-, and Deoxythymidine (DDT)-5′-Monophosphates". Nucleosides and Nucleotides 11, n. 2-4 (febbraio 1992): 947–56. http://dx.doi.org/10.1080/07328319208021749.

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27

Fu, Xiaodan, Lin Zhu, Li Li, Tan Zhang, Meng Li e Haijin Mou. "Eco-friendly preparation of chitooligosaccharides with different degrees of deacetylation from shrimp shell waste and their effects on the germination of wheat seeds". Marine Life Science & Technology 1, n. 1 (novembre 2019): 95–103. http://dx.doi.org/10.1007/s42995-019-00012-3.

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Abstract Production of chitosan and its derivatives by traditional methods involves the excessive use of a reaction solution comprised of sodium hydroxide and hydrochloric acid. Waste water resulting from this process has limited the application of chitosan as a fertilizer as the process causes serious environmental pollution. Specifically, the resulting waste water contains high levels of dissolved nitrogen and minerals from shrimp shells. In this study, an eco-friendly method was established to produce chitooligosaccharides (COS) with different degrees of deacetylation (DDAs) from shrimp shell waste. At a solid-to-solvent ratio of 1:6, the degree of demineralization was above 90% with the treatment of 30 g·L−1 H3PO4, and the degree of deproteinization was above 80% when treated with 30 g·L−1 KOH at 70 °C. Chitosans with different DDAs were obtained by microwave-assisted KOH metathesis and the COS with Mw approximately 1500 Da were then prepared by oxidative degradation. In summary, 33.73 kg H3PO4, 12.77 kg, and 241.31 kg KOH were supplied during the processes of demineralization, deproteinization, and deacetylation of 100 kg shrimp shell waste, respectively. The process water was totally recycled, demonstrating that the shrimp shell could be wholly transformed into fertilizer. The entire process created a product with the fractions of N:P2O5:K2O:COS = 7.94:24.44:10.72:18.27. The test on the germination promotion of wheat seeds revealed that the COS with 72.12% DDA significantly promoted germination. This work demonstrated the use of an eco-friendly preparation method of COS with a specific degree of deacetylation that can be applied as a fertilizer.

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28

LEIPER, James M., Joanne SANTA MARIA, Ann CHUBB, Raymond J. MACALLISTER, Ian G. CHARLES, Guy St J. WHITLEY e Patrick VALLANCE. "Identification of two human dimethylarginine dimethylaminohydrolases with distinct tissue distributions and homology with microbial arginine deiminases". Biochemical Journal 343, n. 1 (24 settembre 1999): 209–14. http://dx.doi.org/10.1042/bj3430209.

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Methylarginines inhibit nitric oxide synthases (NOS). Cellular concentrations of methylarginines are determined in part by the activity of dimethylarginine dimethylaminohydrolase (DDAH; EC 3.5.3.18). We have cloned human DDAH and identified and expressed a second novel DDAH isoform (DDAH I and II respectively). DDAH I predominates in tissues that express neuronal NOS. DDAH II predominates in tissues expressing endothelial NOS. These results strengthen the hypothesis that methylarginine concentration is actively regulated and identify molecular targets for the tissue and cell-specific regulation of methylarginine concentration.

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29

Chen, YingJie, Yunfang Li, Ping Zhang, Jay H. Traverse, Mingxiao Hou, Xin Xu, Masumi Kimoto e Robert J. Bache. "Dimethylarginine dimethylaminohydrolase and endothelial dysfunction in failing hearts". American Journal of Physiology-Heart and Circulatory Physiology 289, n. 5 (novembre 2005): H2212—H2219. http://dx.doi.org/10.1152/ajpheart.00224.2005.

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Congestive heart failure (CHF) is associated with impaired endothelium-dependent nitric oxide (NO)-mediated vasodilation (endothelial dysfunction). We hypothesized that coronary endothelial dysfunction in CHF may be due in part to decreased dimethylarginine dimethylaminohydrolase (DDAH), the enzyme that degrades endogenous inhibitors of NO synthase (NOS), including asymmetric dimethylarginine. Coronary blood flow and the endothelium-dependent vasodilator response to acetylcholine were studied in dogs in which CHF was produced by rapid ventricular pacing for 4 wk. Coronary flow and myocardial O2 consumption at rest and during treadmill exercise were decreased after development of CHF, and the vasodilator response to intracoronary acetylcholine (75 μg/min) was decreased by 39 ± 5%. DDAH activity and DDAH isoform 2 (DDAH-2) protein content were decreased by 53 ± 13% and 58 ± 14%, respectively, in hearts with CHF, whereas endothelial NOS and DDAH isoform 1 (DDAH-1) were increased. Caveolin-1 and protein arginine N-methyltransferase 1, the enzyme that produces asymmetric dimethylarginine, were unchanged. Immunohistochemical staining showed DDAH-1 strongly expressed in coronary endothelium and smooth muscle and in the sarcolemma of cardiac myocytes. In cultured human endothelial cells, DDAH-1 was uniformly distributed in the cytosol and nucleus, whereas DDAH-2 was found only in the cytosol. Decreased DDAH activity and DDAH-2 protein expression may cause accumulation of endogenous inhibitors of endothelial NOS, thereby contributing to endothelial dysfunction in the failing heart.

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30

Lin, Heng-Huei, Tzong-Shyuan Lee, Shing-Jong Lin, Yi-Chen Yeh, Tse-Min Lu e Chiao-Po Hsu. "DDAH-2 alleviates contrast medium iopromide-induced acute kidney injury through nitric oxide synthase". Clinical Science 133, n. 23 (dicembre 2019): 2361–78. http://dx.doi.org/10.1042/cs20190455.

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Abstract Background: Contrast medium-induced acute kidney injury (CI-AKI) is one of the most common causes of hospital-acquired acute renal failure. However, the pathogenesis of CI-AKI remains unclear. Asymmetric dimethylarginine (ADMA) is an endogenous nitric oxide synthase (NOS) inhibitor that is largely metabolised by dimethylarginine dimethylaminohydroxylase (DDAH) in humans. Two isoforms of DDAH exist, namely, DDAH-1 and DDAH-2. In the present study, we examined whether the DDAH-2/ADMA/NOS pathway is involved in the pathogenesis of CI-AKI. Methods and Results: Exposure to the contrast medium iopromide led to increase in creatinine and blood urea nitrogen (BUN) levels, accumulation of ADMA, increase in reactive oxygen species (ROS) generation, and an inflammatory response in mice kidney tissue. The injection of adenovirus-harbouring DDAH-2 lowered renal ADMA levels and had a reno-protective effect against contrast-medium injury by decreasing cell apoptosis, ROS, and fibrosis. By contrast, contrast medium-induced renal injury was exacerbated in heterozygous DDAH-2 knockout mice. In the in vitro study, overexpression of DDAH-2 increased the levels of nitrite and intracellular cGMP, while the DDAH-2 knockdown induced the opposite effect. These findings were also observed in the in vivo sample. Conclusions: Our findings provide the first evidence that the DDAH-2/ADMA/NOS pathway is involved in the pathogenesis of CI-AKI and that the protective effect of DDAH-2 probably arises from the modulation of NOS activity, oxidative stress, and the inflammatory process.

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31

Palm, Fredrik, Maristela L. Onozato, Zaiming Luo e Christopher S. Wilcox. "Dimethylarginine dimethylaminohydrolase (DDAH): expression, regulation, and function in the cardiovascular and renal systems". American Journal of Physiology-Heart and Circulatory Physiology 293, n. 6 (dicembre 2007): H3227—H3245. http://dx.doi.org/10.1152/ajpheart.00998.2007.

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Abstract (sommario):

Asymmetric ( NG, NG)-dimethylarginine (ADMA) inhibits nitric oxide (NO) synthases (NOS). ADMA is a risk factor for endothelial dysfunction, cardiovascular mortality, and progression of chronic kidney disease. Two isoforms of dimethylarginine dimethylaminohydrolase (DDAH) metabolize ADMA. DDAH-1 is the predominant isoform in the proximal tubules of the kidney and in the liver. These organs extract ADMA from the circulation. DDAH-2 is the predominant isoform in the vasculature, where it is found in endothelial cells adjacent to the cell membrane and in intracellular vesicles and in vascular smooth muscle cells among the myofibrils and the nuclear envelope. In vivo gene silencing of DDAH-1 in the rat and DDAH +/− mice both have increased circulating ADMA, whereas gene silencing of DDAH-2 reduces vascular NO generation and endothelium-derived relaxation factor responses. DDAH-2 also is expressed in the kidney in the macula densa and distal nephron. Angiotensin type 1 receptor activation in kidneys reduces the expression of DDAH-1 but increases the expression of DDAH-2. This rapidly evolving evidence of isoform-specific distribution and regulation of DDAH expression in the kidney and blood vessels provides potential mechanisms for nephron site-specific regulation of NO production. In this review, the recent advances in the regulation and function of DDAH enzymes, their roles in the regulation of NO generation, and their possible contribution to endothelial dysfunction in patients with cardiovascular and kidney diseases are discussed.

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32

Wetzel, Michael D., Ting Gao, Kristen Stanley, Timothy K. Cooper, Sidney M. Morris e Alaa S. Awad. "Enhancing kidney DDAH-1 expression by adenovirus delivery reduces ADMA and ameliorates diabetic nephropathy". American Journal of Physiology-Renal Physiology 318, n. 2 (1 febbraio 2020): F509—F517. http://dx.doi.org/10.1152/ajprenal.00518.2019.

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Abstract (sommario):

Endothelial dysfunction, characterized by reduced bioavailability of nitric oxide and increased oxidative stress, is a hallmark characteristic in diabetes and diabetic nephropathy (DN). High levels of asymmetric dimethylarginine (ADMA) are observed in several diseases including DN and are a strong prognostic marker for cardiovascular events in patients with diabetes and end-stage renal disease. ADMA, an endogenous endothelial nitric oxide synthase (NOS3) inhibitor, is selectively metabolized by dimethylarginine dimethylaminohydrolase (DDAH). Low DDAH levels have been associated with cardiac and renal dysfunction, but its effects on DN are unknown. We hypothesized that enhanced renal DDAH-1 expression would improve DN by reducing ADMA and restoring NOS3 levels. DBA/2J mice injected with multiple low doses of vehicle or streptozotocin were subsequently injected intrarenally with adenovirus expressing DDAH-1 (Ad-h-DDAH-1) or vector control [Ad-green fluorescent protein (GFP)], and mice were followed for 6 wk. Diabetes was associated with increased kidney ADMA and reduced kidney DDAH activity and DDAH-1 expression but had no effect on kidney DDAH-2 expression. Ad-GFP-treated diabetic mice showed significant increases in albuminuria, histological changes, glomerular macrophage recruitment, inflammatory cytokine and fibrotic markers, kidney ADMA levels, and urinary thiobarbituric acid reactive substances excretion as an indicator of oxidative stress, along with a significant reduction in kidney DDAH activity and kidney NOS3 mRNA compared with normal mice. In contrast, Ad-h-DDAH-1 treatment of diabetic mice reversed these effects. These data indicate, for the first time, that DDAH-1 mediates renal tissue protection in DN via the ADMA-NOS3-interaction. Enhanced renal DDAH-1 activity could be a novel therapeutic tool for treating patients with diabetes.

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33

Tezel, U., S. G. Pavlostathis e J. A. Pierson. "Effect of didecyl dimethyl ammonium chloride on nitrate reduction in a mixed methanogenic culture". Water Science and Technology 57, n. 4 (1 marzo 2008): 541–46. http://dx.doi.org/10.2166/wst.2008.068.

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Abstract (sommario):

The effect of the quaternary ammonium compound, didecyl dimethyl ammonium chloride (DDAC), on nitrate reduction was investigated at concentrations up to 100 mg/L in a batch assay using a mixed, mesophilic (35°C) methanogenic culture. Glucose was used as the carbon and energy source and the initial nitrate concentration was 70 mg N/L. Dissimilatory nitrate reduction to ammonia (DNRA) and to dinitrogen (denitrification) were observed at DDAC concentrations up to 25 mg/L. At and above 50 mg DDAC/L, DNRA was inhibited and denitrification was incomplete resulting in accumulation of nitrous oxide. At DDAC concentrations above 10 mg/L, production of nitrous oxide, even transiently, resulted in complete, long-term inhibition of methanogenesis and accumulation of volatile fatty acids. Fermentation was inhibited at and above 75 mg DDAC/L. DDAC suppressed microbial growth and caused cell lysis at a concentration 50 mg/L or higher. Most of the added DDAC was adsorbed on the biomass. Over 96% of the added DDAC was recovered from all cultures at the end of the 100-days incubation period, indicating that DDAC did not degrade in the mixed methanogenic culture under the conditions of this study.

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34

Hollenhorst, Marie A., Stefanie B. Bumpus, Megan L. Matthews, J. Martin Bollinger, Neil L. Kelleher e Christopher T. Walsh. "The Nonribosomal Peptide Synthetase Enzyme DdaD TethersNβ-Fumaramoyl-l-2,3-diaminopropionate for Fe(II)/α-Ketoglutarate-Dependent Epoxidation by DdaC during Dapdiamide Antibiotic Biosynthesis". Journal of the American Chemical Society 132, n. 44 (10 novembre 2010): 15773–81. http://dx.doi.org/10.1021/ja1072367.

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35

Hollenhorst, Marie A., Stefanie B. Bumpus, Megan L. Matthews, J. Martin Bollinger, Neil L. Kelleher e Christopher T. Walsh. "The Nonribosomal Peptide Synthetase Enzyme DdaD TethersNβ-Fumaramoyl-l-2,3-diaminopropionate for Fe(II)/α-Ketoglutarate-Dependent Epoxidation by DdaC during Dapdiamide Antibiotic Biosynthesis". Journal of the American Chemical Society 133, n. 5 (9 febbraio 2011): 1609. http://dx.doi.org/10.1021/ja1110128.

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36

Drmić, Z., M. Čačija, H. Virić Gašparić, D. Lemić e R. Bažok. "Phenology of the sugar beet weevil, Bothynoderes punctiventris Germar (Coleoptera: Curculionidae), in Croatia". Bulletin of Entomological Research 109, n. 4 (27 novembre 2018): 518–27. http://dx.doi.org/10.1017/s000748531800086x.

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Abstract (sommario):

AbstractThe sugar beet weevil (SBW), Bothynoderes punctiventris Germar, 1824, is a significant pest in most of Eastern Europe. Here, the SBW is described and its seasonal activity characterized, in terms of its different developmental stages in relation to Julian days (JDs), degree-day accumulations (DDAs), and precipitation, as a key to improving monitoring and forecasting of the pest. The phenology and population characteristics of SBW were investigated in sugar beet fields in eastern Croatia over a 4-year period (2012–2015). By using the degree-day model (lower development threshold of 5°C, no upper development threshold, biofix 1 January), the first emergence of overwintering adults was determined as becoming established when the DDA reached 20. The adult emergence was completed when the DDA reached 428. SBW males emerged first, following which the females dominated the adult population. Overwintering adults were present in the field until early July. In August, adults of the offspring generation began to appear. The eggs laid by the overwintering generation required, on average, 10–15 days to develop into larvae; however, eggs were found in soil samples over a period of 102 days (between JDs 112 and 214). Larvae were present in the soil samples over a period of a maximum of 143 days (the first larvae were established on JD 122 and the last one on JD 265), and pupae were established in the soil over a period of 102 days (between JDs 143 and 245). This study provides important data for understanding SBW population dynamics and developing potential population dynamic models for pest forecasting on a regional scale.

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37

Yang, Jeong-Sun, Sung-Bong Choi, Sang-Yong Park e Sung-Bae Lee. "Analysis of didecydimethylammonium chloride (DDAC) aerosol in inhalation chamber". Analytical Science and Technology 25, n. 5 (25 ottobre 2012): 307–12. http://dx.doi.org/10.5806/ast.2012.25.5.307.

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38

Zhang, Jing, Sa Ma, Wenchang Wang e Zhidong Chen. "Electrochemical Sensing of Bisphenol A by a Didodecyldimethylammonium Bromide-Modified Expanded Graphite Paste Electrode". Journal of AOAC INTERNATIONAL 99, n. 4 (1 luglio 2016): 1066–72. http://dx.doi.org/10.5740/jaoacint.16-0072.

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Abstract (sommario):

Abstract An electrochemical and sensitive sensing of 2,2-bis(4-hydroxyphenyl) propane [bisphenol A (BPA)] was developed based on a didodecyldimethylammonium bromide-modified expanded graphite paste electrode (DDAB-EGPE). The DDAB-EGPE was prepared by suspending an EGPE in a DDAB aqueous solution, and allowing the DDAB to form a hydrophobic film on the expanded graphite surface. Compared with the EGPE, the DDAB-EGPE showed improved electrochemical response of BPA because of the preconcentration of BPA in DDAB via hydrophobic interaction. Due to the electrocatalytic activity of BPA, a sensor for BPA was constructed based on the DDAB-EGPE. The DDAB-EGPE exhibited a wide linear response to BPA ranging from 6.0 × 10−8 to 2.0 × 10−5 mol/L with a detection limit of 7.1 nmol/L at S/N = 3. The designed sensor showed good reproducibility and stability. The proposed sensor was successfully applied to the determination of BPA in three types of real plastic product samples. This sensor presented a simple, rapid, and sensitive platform for the determination of BPA and could become a versatile and powerful tool for food safety.

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39

Eller, Fred J., Mark E. Mankowski, Grant T. Kirker e Gordon W. Selling. "Effects of loblolly pine extract, primary and quaternary alkyl ammonium chlorides combined with burgundy oil from eastern red cedar against subterranean termites and wood-decay fungi". BioResources 16, n. 1 (11 dicembre 2020): 893–910. http://dx.doi.org/10.15376/biores.16.1.893-910.

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Abstract (sommario):

Burgundy oil (BO) from Eastern red cedar provides resistance against termites and wood-decay fungi and is enhanced when combined with an amylose inclusion complex (AIC) containing hexadecylammonium chloride (HAC). Indirect evidence also indicated that a methanol Loblolly pine extract (LPE) was inhibitory against termites. This study compared the effects of HAC and didecyldimethylammonium chloride (DDAC) combined with LPE and BO on termites and wood-decay fungi. Southern pine was treated by vacuum/pressure impregnation and resistance evaluated after exposure to termites and decay fungi. The combination of BO and either HAC/AIC or DDAC/AIC reduced wood mass losses by termites, increased termite mortality, and inhibited all wood-decay fungi. The HAC/AIC and DDAC/AIC resulted in equivalent mass losses by termites and termite mortalities. The DDAC was slightly more inhibitory than the HAC against wood-decay fungi. Given the slight advantage of DDAC over HAC and because DDAC is currently used to preserve wood, DDAC might be preferred over HAC. The LPE had a very minor effect on mass loss by termites, termite mortality, and only a slight inhibitory effect on G. trabeum and T. versicolor, while R. placenta and I. lacteus were unaffected. Higher concentrations of DDAC and/or LPE might improve protection against termites and wood-decay fungi.

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40

Raihan, Raihan. "IMPLEMENTASI PEMIKIRAN DAKWAH MOHAMMAD NATSIR DI DEWAN DAKWAH ISLAMIYAH INDONESIA PROVINSI ACEH". Jurnal Ilmiah Islam Futura 15, n. 1 (1 agosto 2015): 67. http://dx.doi.org/10.22373/jiif.v15i1.559.

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Abstract (sommario):

Mohammad Natsir was one of the da’wa figure where his thoughts covered various fields. He was the founder DDII (Dewan Da'wah Islamiyah Indonesia) who was assessed consistently carried out the Islamic da’wa until the end of his life. As the result of his struggle, related to the vision and mission of the center of DDII, DDII Aceh should not be much different from that set by the center. But in reality, when it is seen through the aspect of the activities being carried out have not been fully applied by Aceh DDII. The result of this study shows that the struggle of Mohammad Natsir as well as the extension of the center management is related to the vision and the mission developed by the Aceh Provincial DDII is not different from that being set by the center. Similarly, the majority of programs are set by Aceh DDII has much in common with the da’wa activities that had been carried out by Mohammad Natsir when leading DDII, namely to conducted promoting and routine qur’anic recitation, building mosques, hampering the effort to silt the creed as well as other programs aimed at improving the Islamic da’wa quality. However, the performance of Aceh DDII is still seemed less productive due to the involvement of management which some still focus on less da’wa activities. In addition, the Aceh DDII is lack of operational funds in carrying out various activities which bring about some programs have been delayed, or even failure in its implementation.

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41

Volti, Giovanni Li, Valeria Sorrenti, Rosaria Acquaviva, Paolo Murabito, Antonino Gullo, Maria Luisa Barcellona, Fabio Galvano et al. "Effect of Ischemia–Reperfusion on Renal Expression and Activity of N G-N G-Dimethylarginine Dimethylaminohydrolases". Anesthesiology 109, n. 6 (1 dicembre 2008): 1054–62. http://dx.doi.org/10.1097/aln.0b013e31818d8a77.

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Abstract (sommario):

Background Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase. It is degraded by the enzyme dimethylarginine dimethylaminohydrolase (DDAH). Methods Rats (n = 50) underwent to 45 min of renal ischemia followed by 30 min, 1 h, and 3 h of reperfusion. Expression of endothelial nitric oxide synthase, inducible nitric oxide synthase, DDAH-1, DDAH-2, renal DDAH activity, plasma NO2(-)/NO3(-), and ADMA levels were evaluated. Results Inducible nitric oxide synthase expression increased, as confirmed by both plasma (11.89 +/- 1.02, 15.56 +/- 0.93, 11.82 +/- 0.86, 35.05 +/- 1.28, and 43.89 +/- 1.63 nmol/ml in the control, ischemic, 30-min, 1-h, and 3-h groups, respectively) and renal (4.81 +/- 0.4, 4.85 +/- 1, 9.42 +/- 0.7, 15.42 +/- 0.85, and 22.03 +/- 1.11 nmol/mg protein) formations of NO2(-)/NO3(-). DDAH-1 expression decreased after reperfusion, whereas DDAH-2 increased after 30 min, returning to basal levels after 3 h. Total DDAH activity was reduced during all times of reperfusion. Both plasma (0.41 +/- 0.03, 0.43 +/- 0.05, 0.62 +/- 0.02, 0.71 +/- 0.02, and 0.41 +/- 0.01 nmol/ml in the control, ischemic, 30-min, 1-h, and 3-h groups, respectively) and renal (1.51 +/- 0.01, 1.5 +/- 0.01, 1.53 +/- 0.01, 2.52 +/- 0.04, and 4.48 +/- 0.03 nmol/mg protein in the control, ischemic, 30-min, 1-h, and 3-h groups, respectively) concentrations of ADMA increased. Conclusions Results suggest that ischemia-reperfusion injury leads to reduced DDAH activity and modification of different DDAH isoform expression, thus leading to increased ADMA levels, which may lead to increased cardiovascular risk.

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42

Uematsu, Keiji, Fumihiko Okumura, Syunsuke Tonogai, Akiko Joo-Okumura, Dawit Hailu Alemayehu, Akihiko Nishikimi, Yoshinori Fukui, Kunio Nakatsukasa e Takumi Kamura. "ASB7 regulates spindle dynamics and genome integrity by targeting DDA3 for proteasomal degradation". Journal of Cell Biology 215, n. 1 (3 ottobre 2016): 95–106. http://dx.doi.org/10.1083/jcb.201603062.

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Abstract (sommario):

Proper dynamic regulation of the spindle is essential for successful cell division. However, the molecular mechanisms that regulate spindle dynamics in mitosis are not fully understood. In this study, we show that Cullin 5–interacting suppressor of cytokine signaling box protein ASB7 ubiquitinates DDA3, a regulator of spindle dynamics, thereby targeting it for proteasomal degradation. The presence of microtubules (MTs) prevented the ASB7–DDA3 interaction, thus stabilizing DDA3. Knockdown of ASB7 decreased MT polymerization and increased the proportion of cells with unaligned chromosomes, and this phenotype was rescued by deletion of DDA3. Collectively, these data indicate that ASB7 plays a crucial role in regulating spindle dynamics and genome integrity by controlling the expression of DDA3.

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Jang, Chang-Young, Jim Wong, Judith A. Coppinger, Akiko Seki, John R. Yates e Guowei Fang. "DDA3 recruits microtubule depolymerase Kif2a to spindle poles and controls spindle dynamics and mitotic chromosome movement". Journal of Cell Biology 181, n. 2 (14 aprile 2008): 255–67. http://dx.doi.org/10.1083/jcb.200711032.

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Dynamic turnover of the spindle is a driving force for chromosome congression and segregation in mitosis. Through a functional genomic analysis, we identify DDA3 as a previously unknown regulator of spindle dynamics that is essential for mitotic progression. DDA3 depletion results in a high frequency of unaligned chromosomes, a substantial reduction in tension across sister kinetochores at metaphase, and a decrease in the velocity of chromosome segregation at anaphase. DDA3 associates with the mitotic spindle and controls microtubule (MT) dynamics. Mechanistically, DDA3 interacts with the MT depolymerase Kif2a in an MT-dependent manner and recruits Kif2a to the mitotic spindle and spindle poles. Depletion of DDA3 increases the steady-state levels of spindle MTs by reducing the turnover rate of the mitotic spindle and by increasing the rate of MT polymerization, which phenocopies the effects of partial knockdown of Kif2a. Thus, DDA3 represents a new class of MT-destabilizing protein that controls spindle dynamics and mitotic progression by regulating MT depolymerases.

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Vardigan, Mary. "DDI Timeline". IASSIST Quarterly 37, n. 1-4 (26 maggio 2014): 51. http://dx.doi.org/10.29173/iq502.

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45

Lai, Yun-Chien, Chi-Jung Tai, Mohamed El-Shazly, Yu-Che Chuang, Shu-Tuan Chiang, Yi-Hong Tsai, Dezső Csupor, Judith Hohmann, Yang-Chang Wu e Fang-Rong Chang. "Quantification and Simplified Detoxification Investigation on Fuzi, Root of Aconitum carmichaelii". Natural Product Communications 14, n. 10 (ottobre 2019): 1934578X1988154. http://dx.doi.org/10.1177/1934578x19881548.

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Fuzi (lateral root of Aconitum carmichaelii) has been used for millennia in Traditional Chinese Medicine (TCM) and Ayurveda to treat cancer and cardiovascular diseases. Fuzi must be processed before use to decrease the concentration of its toxic alkaloids. Detoxification during processing occurs through the transformation of diester-diterpenoid alkaloids (DDAs) to monoester-diterpenoid alkaloids (MDAs). However, traditional detoxification methods are time-consuming and expensive on large-scale production. To develop efficient detoxification protocols to reduce unnecessary processing procedure and keep the maximum functional contents from raw Fuzi, we replicated the traditional procedure and quantified the DDAs and MDAs by UPLC-MS/MS and UPLC-PDA during different steps and conditions of processing. With due consideration of obtained data, we concluded that soaking in Danba solution and the washing steps were inefficient traditional processing methods. The detoxification effect of steaming (56.3 ± 0.27 μg/g DDAs, lowest after steaming) was weaker and slower than boiling (5.8 ± 0.33 μg/g DDAs, lowest after boiling). Moreover, roasting at 105℃ showed better effect in lowering the DDAs (5.8 ± 0.33 μg/g DDAs) and increasing the MDAs (729.1 ± 1.22 μg/g MDAs, highest) than roasting at 60℃ (17.3 ± 0.65 μg/g DDAs; 504.0 ± 0.99 μg/g MDAs). With these highly reliable analytic data, we established an efficient and referenceable detoxification protocol for Fuzi TCM products, in which DDAs and MDAs should legitimately follow the safe and specific ranges stipulated in pharmacopeias.

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ZHAO, TIEJUN, HEZHONG CHEN, LIXIN YANG, HAI JIN, ZHIGANG LI, LIN HAN, FANGLIN LU e ZHIYUN XU. "DDAB-MODIFIED TPGS-b-(PCL-ran-PGA) NANOPARTICLES AS ORAL ANTICANCER DRUG CARRIER FOR LUNG CANCER CHEMOTHERAPY". Nano 08, n. 02 (aprile 2013): 1350014. http://dx.doi.org/10.1142/s1793292013500148.

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Oral chemotherapy is a great way to cancer treatment because it is less stressful being that the patient will have less hospital visits and can still maintain a close relationship with health care professionals. In this research, three types of nanoparticle formulation from commercial PCL and self-synthesized TPGS-b-(PCL-ran-PGA) diblock copolymer were fabricated for oral delivery of antitumor agents, including DDAB-modified PCL nanoparticles, unmodified TPGS-b-(PCL-ran-PGA) nanoparticles and DDAB-modified TPGS-b-(PCL-ran-PGA) nanoparticles. Firstly, the TPGS-b-(PCL-ran-PGA) diblock copolymer was synthesized and characterized. DDAB was adopted to increase retention time at the cell surface, thus increasing the chances of nanoparticle uptake by the gastrointestinal mucosa and improving drug absorption. The TPGS-b-(PCL-ran-PGA) nanoparticles were found by FESEM of spherical shape and around 200 nm in diameter. The surface charge of TPGS-b-(PCL-ran-PGA) nanoparticles was reversed from anionic to cationic after DDAB modification. The DDAB-modified TPGS-b-(PCL-ran-PGA) nanoparticles have significantly higher level of the cell uptake than that of DDAB-modified PCL nanoparticles and unmodified TPGS-b-(PCL-ran-PGA) nanoparticles. In vitro cell viability studies showed advantages of the DDAB-modified TPGS-b-(PCL-ran-PGA) nanoparticles over Taxotere® in terms of cytotoxicity against A549 cells. In conclusion, oral chemotherapy by DDAB-modified TPGS-b-(PCL-ran-PGA) nanoparticle formulation may provide a promising outcome for lung cancer patients.

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J, Rix,, e Tinz, M. "Monitoring of transport infrastructure with Copernicus (DDGI Traffic) Verkehrsinfrastrukturmonitoring mit Copernicus (DDGI Verkehr)". GIS Business 12, n. 3 (20 giugno 2019): 42–53. http://dx.doi.org/10.26643/gis.v12i3.5183.

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48

Ferrigno, Andrea, Vittoria Rizzo, Alberto Bianchi, Laura G. Di Pasqua, Clarissa Berardo, Plinio Richelmi e Mariapia Vairetti. "Changes in ADMA/DDAH Pathway after Hepatic Ischemia/Reperfusion Injury in Rats: The Role of Bile". BioMed Research International 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/627434.

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We investigated the effects of hepatic ischemia/reperfusion (I/R) injury on asymmetric dimethylarginine (ADMA, a nitric oxide synthase inhibitor), protein methyltransferase (PRMT) and dimethylarginine dimethylaminohydrolase (DDAH) (involved, resp., in ADMA synthesis and degradation), and the cationic transporter (CAT). Male Wistar rats were subjected to 30 or 60 min hepatic ischemia followed by 60 min reperfusion. ADMA levels in serum and bile were determined. Tissue ADMA, DDAH activity, DDAH-1 and CAT-2 protein, DDAH-1 and PRMT-1 mRNA expression, GSH/GSSG, ROS production, and lipid peroxidation were detected. ADMA was found in bile. I/R increased serum and bile ADMA levels while an intracellular decrease was detected after 60 min ischemia. Decreased DDAH activity, mRNA, and protein expression were observed at the end of reperfusion. No significant difference was observed in GSH/GSSG, ROS, lipid peroxidation, and CAT-2; a decrease in PRMT-1 mRNA expression was found after I/R. Liver is responsible for the biliary excretion of ADMA, as documented here for the first time, and I/R injury is associated with an oxidative stress-independent alteration in DDAH activity. These data are a step forward in the understanding of the pathways that regulate serum, tissue, and biliary levels of ADMA in which DDAH enzyme plays a crucial role.

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Yang, Mengbi, Xiaoyu Ji e Zhong Zuo. "Relationships between the Toxicities of Radix Aconiti Lateralis Preparata (Fuzi) and the Toxicokinetics of Its Main Diester-Diterpenoid Alkaloids". Toxins 10, n. 10 (26 settembre 2018): 391. http://dx.doi.org/10.3390/toxins10100391.

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The processed lateral root of Aconitum carmichaelii Deb (Aconiti Radix lateralis praeparata or Fuzi) is a potent traditional herbal medicine extensively used in treatment of cardiovascular diseases, rheumatism arthritis, and bronchitis in many Asian countries. Although Fuzi has promising therapeutic effects, its toxicities are frequently observed. Three main C19-diester-diterpenoid alkaloids (DDAs) are believed to be the principal toxins of the herb. Although toxicokinetic profiles of the toxic DDAs have already been examined in several studies, they have seldom been correlated with the toxicities of Fuzi. The current article aimed to investigate the relationship between the up-to-date toxicokinetic data of the toxic DDAs and the existing evidence of the toxic effects of Fuzi. Relationships between the cardiac toxicity and the plasma and heart concentration of DDAs in mice and rats were established. Based on our findings, clinical monitoring of the plasma concentrations of DDAs of Fuzi is recommended to prevent potential cardiac toxicities. Additionally, caution with respect to potential hepatic and renal toxicity induced by Fuzi should be exercised. In addition, further analyses focusing on the preclinical tissue distribution profile of DDAs and on the long-term toxicokinetic-toxicity correlation of DDAs are warranted for a better understanding of the toxic mechanisms and safer use of Fuzi.

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Zheng, Fei, Xiao-Yu Yang, Peng-Qing Bi, Meng-Si Niu, Cheng-Kun Lv, Lin Feng, Xiao-Tao Hao e Kenneth P. Ghiggino. "Improved compatibility of DDAB-functionalized graphene oxide with a conjugated polymer by isocyanate treatment". RSC Advances 7, n. 29 (2017): 17633–39. http://dx.doi.org/10.1039/c6ra28652f.

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