51 research outputs found

    Nuclear Receptor-Like Structure and Interaction of Congenital Heart Disease-Associated Factors GATA4 and NKX2-5

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    Aims Transcription factor GATA4 is a dosage sensitive regulator of heart development and alterations in its level or activity lead to congenital heart disease (CHD). GATA4 has also been implicated in cardiac regeneration and repair. GATA4 action involves combinatorial interaction with other cofactors such as NKX2-5, another critical cardiac regulator whose mutations also cause CHD. Despite its critical importance to the heart and its evolutionary conservation across species, the structural basis of the GATA4-NKX2-5 interaction remains incompletely understood. Methods and Results A homology model was constructed and used to identify surface amino acids important for the interaction of GATA4 and NKX2-5. These residues were subjected to site-directed mutagenesis, and the mutant proteins were characterized for their ability to bind DNA and to physically and functionally interact with NKX2-5. The studies identify 5 highly conserved amino acids in the second zinc finger (N272, R283, Q274, K299) and its C-terminal extension (R319) that are critical for physical and functional interaction with the third alpha helix of NKX2-5 homeodomain. Integration of the experimental data with computational modeling suggests that the structural arrangement of the zinc finger-homeodomain resembles the architecture of the conserved DNA binding domain of nuclear receptors. Conclusions The results provide novel insight into the structural basis for protein-protein interactions between two important classes of transcription factors. The model proposed will help to elucidate the molecular basis for disease causing mutations in GATA4 and NKX2-5 and may be relevant to other members of the GATA and NK classes of transcription factors.Peer reviewe

    Discovery and Characterization of ORM‐11372, a Novel Inhibitor of the Sodium‐Calcium Exchanger with Positive Inotropic Activity

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    Background and purpose The lack of selective sodium‐calcium exchanger (NCX) inhibitors has hampered the exploration of physiological and pathophysiological roles of cardiac NCX 1.1. We aimed to discover more potent and selective drug like NCX 1.1. inhibitor. Experimental approach A flavan series‐based pharmacophore model was constructed. Virtual screening helped us identify a novel scaffold for NCX inhibition. A distinctively different NCX 1.1 inhibitor, ORM‐11372, was discovered after lead optimization. Its potency against human and rat NCX 1.1 and selectivity against other ion channels was assessed. The cardiovascular effects of ORM‐11372 were studied in normal and infarcted rats, and rabbits. Human cardiac safety was studied ex‐vivo using human ventricular trabeculae. Key results ORM‐11372 inhibited human NCX 1.1 reverse and forward currents; IC50 values were 5 and 6 nM, respectively. ORM‐11372 inhibited human cardiac sodium 1.5 (INa) and hERG KV11.1 currents (IhERG) in a concentration‐dependent manner; IC50 values were 23.2 and 10.0 μM. ORM‐11372 caused no changes in action potential duration; short term variability and triangulation were observed for concentrations of upto 10 μM. ORM‐11372 induced positive inotropic effects in 18 ± 6% and 35 ± 8% anesthetized rats with myocardial infarctions and rabbits, respectively; no other haemodynamic effects were observed, except improved relaxation at the lowest dose. Conclusion and implications ORM‐11372, a unique, novel, and potent inhibitor of human and rat NCX 1.1, is a positive inotropic compound. NCX inhibition can induce clinically relevant improvements in left ventricular contractions without affecting relaxation, heart rate, or blood pressure, without pro‐arrhythmic risk

    Discovery and characterization of ORM-11372, a novel inhibitor of the sodium-calcium exchanger with positive inotropic activity

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    BACKGROUND AND PURPOSE: The lack of selective sodium-calcium exchanger (NCX) inhibitors has hampered the exploration of physiological and pathophysiological roles of cardiac NCX 1.1. We aimed to discover more potent and selective drug like NCX 1.1 inhibitor. EXPERIMENTAL APPROACH: A flavan series-based pharmacophore model was constructed. Virtual screening helped us identify a novel scaffold for NCX inhibition. A distinctively different NCX 1.1 inhibitor, ORM-11372, was discovered after lead optimization. Its potency against human and rat NCX 1.1 and selectivity against other ion channels was assessed. The cardiovascular effects of ORM-11372 were studied in normal and infarcted rats and rabbits. Human cardiac safety was studied ex vivo using human ventricular trabeculae. KEY RESULTS: ORM-11372 inhibited human NCX 1.1 reverse and forward currents; IC(50) values were 5 and 6 nM respectively. ORM-11372 inhibited human cardiac sodium 1.5 (I(Na) ) and hERG K(V) 11.1 currents (I(hERG) ) in a concentration-dependent manner; IC(50) values were 23.2 and 10.0 μM. ORM-11372 caused no changes in action potential duration; short-term variability and triangulation were observed for concentrations of up to 10 μM. ORM-11372 induced positive inotropic effects of 18 ± 6% and 35 ± 8% in anaesthetized rats with myocardial infarctions and in healthy rabbits respectively; no other haemodynamic effects were observed, except improved relaxation at the lowest dose. CONCLUSION AND IMPLICATIONS: ORM-11372, a unique, novel, and potent inhibitor of human and rat NCX 1.1, is a positive inotropic compound. NCX inhibition can induce clinically relevant improvements in left ventricular contractions without affecting relaxation, heart rate, or BP, without pro-arrhythmic risk.Peer reviewe

    Discovery and development of ODM-204: A Novel nonsteroidal compound for the treatment of castration-resistant prostate cancer by blocking the androgen receptor and inhibiting CYP17A1

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    We report the discovery of a novel nonsteroidal dual-action compound, ODM-204, that holds promise for treating patients with castration-resistant prostate cancer (CRPC), an advanced form of prostate cancer characterised by high androgen receptor (AR) expression and persistent activation of the AR signaling axis by residual tissue androgens. For ODM-204, has a dual mechanism of action. The compound is anticipated to efficiently dampen androgenic stimuli in the body by inhibiting CYP17A1, the prerequisite enzyme for the formation of dihydrotestosterone (DHT) and testosterone (T), and by blocking AR with high affinity and specificity. In our study, ODM-204 inhibited the proliferation of androgen-dependent VCaP and LNCaP cells in vitro and reduced significantly tumour growth in a murine VCaP xenograft model in vivo. Intriguingly, after a single oral dose of 10-30 mg/kg, ODM-204 dose-dependently inhibited adrenal and testicular steroid production in sexually mature male cynomolgus monkeys. Similar results were obtained in human chorionic gonadotropin-treated male rats. In rats, leuprolide acetate-mediated (LHRH agonist) suppression of the circulating testosterone levels and decrease in weights of androgen-sensitive organs was significantly and dose-dependently potentiated by the co-administration of ODM-204. ODM-204 was well tolerated in both rodents and primates. Based on our data, ODM-204 could provide an effective therapeutic option for men with CRPC.</p

    The Coordination of Leaf Photosynthesis Links C and N Fluxes in C3 Plant Species

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    Photosynthetic capacity is one of the most sensitive parameters in vegetation models and its relationship to leaf nitrogen content links the carbon and nitrogen cycles. Process understanding for reliably predicting photosynthetic capacity is still missing. To advance this understanding we have tested across C3 plant species the coordination hypothesis, which assumes nitrogen allocation to photosynthetic processes such that photosynthesis tends to be co-limited by ribulose-1,5-bisphosphate (RuBP) carboxylation and regeneration. The coordination hypothesis yields an analytical solution to predict photosynthetic capacity and calculate area-based leaf nitrogen content (Na). The resulting model linking leaf photosynthesis, stomata conductance and nitrogen investment provides testable hypotheses about the physiological regulation of these processes. Based on a dataset of 293 observations for 31 species grown under a range of environmental conditions, we confirm the coordination hypothesis: under mean environmental conditions experienced by leaves during the preceding month, RuBP carboxylation equals RuBP regeneration. We identify three key parameters for photosynthetic coordination: specific leaf area and two photosynthetic traits (k3, which modulates N investment and is the ratio of RuBP carboxylation/oxygenation capacity () to leaf photosynthetic N content (Npa); and Jfac, which modulates photosynthesis for a given k3 and is the ratio of RuBP regeneration capacity (Jmax) to). With species-specific parameter values of SLA, k3 and Jfac, our leaf photosynthesis coordination model accounts for 93% of the total variance in Na across species and environmental conditions. A calibration by plant functional type of k3 and Jfac still leads to accurate model prediction of Na, while SLA calibration is essentially required at species level. Observed variations in k3 and Jfac are partly explained by environmental and phylogenetic constraints, while SLA variation is partly explained by phylogeny. These results open a new avenue for predicting photosynthetic capacity and leaf nitrogen content in vegetation models

    Predictive proteochemometric models for kinases derived from 3D protein field-based descriptors

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    Proteochemometrics, a method that simultaneously uses protein and ligand description, was used to model the target-ligand interaction space of 95 kinases and 1572 inhibitors. To build models, we applied 3-dimensional field-based description of the receptors, which allows the visualization of receptor and ligand features relevant for activity within the spatial framework of the binding sites. Receptor fields were derived from knowledge-based potentials and Schrodinger's WaterMaps, while ligands were described by different 1D, 2D and 3D descriptors. Besides good interpretability, which is important for inhibitor design, the obtained proteochemometric models also predicted external test sets with active and inactive ligands or additional protein targets for ligands with more than 80% accuracy and AUCs above 0.8.Peer reviewe

    Eigenenergie-LAM: Übergabestation für Packstücke, Behälter, Kartonagen, Ladungsträger und Paletten (Europaletten und in Erweiterung auch für Industrie-, Düsseldorfer und Chemiepaletten)

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    Die Erfindung bezieht sich auf eine Transporteinrichtung mit einem Übergabeelement (1, 1'), das eine erste Transportgutaufnahme (7, 8) für ein Transportgut (15) aufweist, und mit einem Transportmittel (14, 14'), das eine zweite Aufnahmeeinrichtung (17, 18) für ein Transportgut (15) aufweist, wobei das Übergabeelement und das Transportmittel relativ zueinander bewegbar sind, wobei das Übergabeelement und das Transportmittel derart eingerichtet sind, dass beim gegenseitigen Passieren des Übergabeelementes und des Transportmittels ein Element des Transportmittels oder des mit ihm transportierten Transportgutes an einem Element des Übergabeelementes anstößt oder umgekehrt, derart, dass ein Impuls zwischen dem Transportmittel und dem Übergabeelement übertragen wird, wobei der übertragene Impuls in dem Transportmittel und/oder dem Übergabeelement derart umgelenkt wird, dass eine Transportgutaufnahme (7, 8, 17, 18) des Transportmittels und/oder des Übergabeelementes quer zu der relativen Bewegungsrichtung (13) von Übergabeelement und Transportmittel bewegt wird derart, dass ein Transportgut durch eine der Transportgutaufnahmen von der jeweils anderen Transportgutaufnahme abgehoben oder auf dieser abgesetzt wird. Ein Transportgut kann damit praktisch schlupffrei und damit auch schonend, auch ohne Zufuhr externer Energie übergeben werden
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