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1.
Open Res Eur ; 1: 69, 2021.
Article in English | MEDLINE | ID: mdl-37645170

ABSTRACT

Background: The coronavirus disease 2019 (COVID-19) global pandemic required a rapid and effective response. This included ethical and legally appropriate sharing of data. The European Commission (EC) called upon the Research Data Alliance (RDA) to recruit experts worldwide to quickly develop recommendations and guidelines for COVID-related data sharing. Purpose: The purpose of the present work was to explore how the RDA succeeded in engaging the participation of its community of scientists in a rapid response to the EC request. Methods: A survey questionnaire was developed and distributed among RDA COVID-19 work group members. A mixed-methods approach was used for analysis of the survey data. Results: The three constructs of radical collaboration (inclusiveness, distributed digital practices, productive and sustainable collaboration) were found to be well supported in both the quantitative and qualitative analyses of the survey data. Other social factors, such as motivation and group identity were also found to be important to the success of this extreme collaborative effort. Conclusions: Recommendations and suggestions for future work were formulated for consideration by the RDA to strengthen effective expert collaboration and interdisciplinary efforts.

2.
Wellcome Open Res ; 5: 267, 2020.
Article in English | MEDLINE | ID: mdl-33501381

ABSTRACT

The systemic challenges of the COVID-19 pandemic require cross-disciplinary collaboration in a global and timely fashion. Such collaboration needs open research practices and the sharing of research outputs, such as data and code, thereby facilitating research and research reproducibility and timely collaboration beyond borders. The Research Data Alliance COVID-19 Working Group recently published a set of recommendations and guidelines on data sharing and related best practices for COVID-19 research. These guidelines include recommendations for clinicians, researchers, policy- and decision-makers, funders, publishers, public health experts, disaster preparedness and response experts, infrastructure providers from the perspective of different domains (Clinical Medicine, Omics, Epidemiology, Social Sciences, Community Participation, Indigenous Peoples, Research Software, Legal and Ethical Considerations), and other potential users. These guidelines include recommendations for researchers, policymakers, funders, publishers and infrastructure providers from the perspective of different domains (Clinical Medicine, Omics, Epidemiology, Social Sciences, Community Participation, Indigenous Peoples, Research Software, Legal and Ethical Considerations). Several overarching themes have emerged from this document such as the need to balance the creation of data adherent to FAIR principles (findable, accessible, interoperable and reusable), with the need for quick data release; the use of trustworthy research data repositories; the use of well-annotated data with meaningful metadata; and practices of documenting methods and software. The resulting document marks an unprecedented cross-disciplinary, cross-sectoral, and cross-jurisdictional effort authored by over 160 experts from around the globe. This letter summarises key points of the Recommendations and Guidelines, highlights the relevant findings, shines a spotlight on the process, and suggests how these developments can be leveraged by the wider scientific community.

3.
Neurochem Int ; 52(1-2): 235-40, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17655979

ABSTRACT

Human alpha1 and hyperekplexia mutant alpha1(R271L) glycine receptors (GlyRs) were transiently expressed in human embryonic kidney 293 cells for [3H]strychnine binding. Binding parameters were determined using a ternary allosteric model. The hyperekplexia mutation increased the positive cooperativity of 0.3 mM propofol and glycine binding by about six times: the cooperativity factor beta was 0.26 for alpha1 GlyRs and 0.04 for alpha1(R271L) GlyRs. Thus, propofol restored the potency of glycine impaired by the mutation. Five nortropeines, i.e. substituted benzoates of nortropine and a new compound, nortropisetron were prepared and also examined on [3H]strychnine binding. They showed nanomolar displacing potencies amplified by the hyperekplexia mutation. The affinity of nor-O-zatosetron (2.6 nM) is one of the highest reported for GlyRs. This binding test offers an in vitro method to evaluate agents against neurological disorders associated with inherited mutations of GlyRs.


Subject(s)
Allosteric Regulation , Glycine/pharmacology , Mutation , Propofol/pharmacology , Receptors, Glycine/genetics , Strychnine/metabolism , Cell Line , Humans , Models, Molecular , Protein Conformation , Radioligand Assay , Receptors, Glycine/chemistry , Tritium
4.
Bioorg Med Chem ; 16(4): 2086-92, 2008 Feb 15.
Article in English | MEDLINE | ID: mdl-18053729

ABSTRACT

(Hetero)aromatic mono- and diesters of tropine and nortropine were prepared. Modulation of [3H]strychnine binding to glycine receptors of rat spinal cord was examined with a ternary allosteric model. The esters displaced [3H]strychnine binding with nano- or micromolar potencies and strong negative cooperativity. Coplanarity and distance of the ester moieties of diesters affected the binding affinity being nanomolar for isophthaloyl-bistropane and nortropeines. Nortropisetron had the highest affinity (K(A) approximately 10 nM). Two esters displayed negative cooperativity with glycine in displacement, while three esters of low-affinity and nortropisetron exerted positive cooperativity with glycine.


Subject(s)
Allosteric Site , Receptors, Glycine/metabolism , Tropanes/pharmacology , Animals , Binding, Competitive , Esters , Protein Binding/drug effects , Rats , Spinal Cord , Strychnine/chemistry , Tropanes/chemical synthesis
5.
J Med Chem ; 48(16): 5203-14, 2005 Aug 11.
Article in English | MEDLINE | ID: mdl-16078839

ABSTRACT

The goal of this study was to develop a series of allopregnanolone analogues substituted by conformationally constrained 17beta side chains to obtain additional information about the structure-activity relationship of 5alpha-reduced steroids to modulate GABA(A) receptors. Specifically, we introduced alkynyl-substituted 17beta side chains in which the triple bond is either directly attached to the 17beta-position or to the 21-position of the steroid skeleton. Furthermore, we investigated the effects of C22 and C20 modification. The in vitro binding affinity for the GABA(A) receptor of the new analogues was measured by allosteric displacement of the specific binding of [(3)H]4'-ethynyl-4-n-propyl-bicycloorthobenzoate (EBOB) to GABA(A) receptors on synaptosomal membranes of rat cerebellum. An allosteric binding model that has been successfully applied to ionotropic glycine receptors was employed. The most active derivative is (20R)-17beta-(1-hydroxy-2,3-butadienyl)-5alpha-androstane-3-ol (20), which possesses low nanomolar potency to modulate cerebellar GABA(A) receptors and is 71 times more active than the control compound allopregnanolone. Theoretical conformational analysis was employed in an attempt to correlate the in vitro results with the active conformations of the most potent of the new analogues.


Subject(s)
Androstanols/chemical synthesis , GABA Modulators/chemical synthesis , Receptors, GABA-A/drug effects , Allosteric Site , Androstanols/chemistry , Androstanols/pharmacology , Animals , Cerebellum/drug effects , Cerebellum/metabolism , GABA Modulators/chemistry , GABA Modulators/pharmacology , In Vitro Techniques , Male , Models, Molecular , Molecular Conformation , Protein Subunits/metabolism , Rats , Rats, Wistar , Structure-Activity Relationship , Synaptosomes/drug effects , Synaptosomes/metabolism
6.
Neurosci Lett ; 383(1-2): 127-30, 2005.
Article in English | MEDLINE | ID: mdl-15936524

ABSTRACT

The ionophore function of gamma-aminobutyric acid A (GABA(A)) receptors was studied by whole-cell patch clamp electrophysiology in primary cultures of rat cerebellar cortex. Chloride currents elicited by 1 microM GABA were potentiated by allopregnanolone with a plateau of high affinity (EC(50) = 14 nM) and a peak of potentiation around 1 microM allopregnanolone. Furosemide (0.1 mM) eliminated the high affinity phase and increased the EC(50) to 685 nM. GABA(A) receptors of rat cerebellar synaptosomal membranes were labelled with [(3)H]ethynylbicycloorthobenzoate (EBOB). Allopregnanolone displaced [(3)H]EBOB binding with IC(50) = 320 nM. The displacing potency of allopregnanolone was strongly enhanced (IC(50) = 39 nM) in the presence of 400 nM GABA and 60 nM SR 95531. Nanomolar potentiation by allopregnanolone can be associated with cerebellar GABA(A) receptors containing alpha(6), beta(2-3) and delta subunits. This might be suitable for physiological modulation of tonic inhibitory neurotransmission via extrasynaptic GABA(A) receptors in cerebellar granule cells by neurosteroids.


Subject(s)
Cerebellar Cortex/cytology , Neurons/drug effects , Pregnanolone/pharmacology , Receptors, GABA-A/physiology , Analysis of Variance , Animals , Animals, Newborn , Binding, Competitive/drug effects , Bridged Bicyclo Compounds, Heterocyclic/pharmacokinetics , Cells, Cultured , Cerebellar Cortex/drug effects , Chlorides/metabolism , Dose-Response Relationship, Drug , Drug Interactions , Furosemide/pharmacology , GABA Antagonists/pharmacology , Membrane Potentials/drug effects , Membrane Potentials/physiology , Patch-Clamp Techniques/methods , Pyridazines/pharmacology , Rats , Rats, Wistar , gamma-Aminobutyric Acid/pharmacology
7.
Eur J Pharmacol ; 514(1): 17-24, 2005 May 02.
Article in English | MEDLINE | ID: mdl-15878320

ABSTRACT

[(3)H]Granisetron binding to 5-HT(3) type serotonin receptors was examined in homogenates of rat forebrain and NG 108-15 cells. We have applied an allosteric model to 5-HT(3) receptor binding for the first time. Slope factors of displacement improved the modelling. Serotonin displaced [(3)H]granisetron binding with micromolar potency in forebrain and with nanomolar potency in NG 108-15 cells. Racemic and (+)verapamil, ifenprodil and GYKI-46903 were used as representative allosteric inhibitors of 5-HT(3) receptors. They displaced [(3)H]granisetron binding with great negative cooperativity (alpha>10) and exerted great negative cooperativity with serotonin binding (beta>10). Great negative cooperativity of these agents with serotonin and [(3)H]granisetron binding cannot be distinguished from dual competitive displacement. Trichloroethanol (data from literature) had no cooperativity with [(3)H]granisetron binding (alpha~1) and exhibit positive cooperativity with serotonin (beta<1) in displacement. The allosteric model can lead to a more quantitative method in vitro to develop allosteric agents for 5-HT(3) receptors.


Subject(s)
Receptors, Serotonin, 5-HT3/chemistry , Receptors, Serotonin, 5-HT3/metabolism , Adrenergic alpha-Antagonists/pharmacology , Algorithms , Allosteric Regulation , Animals , Binding, Competitive/drug effects , Cell Line, Tumor , Dose-Response Relationship, Drug , Granisetron/metabolism , Hybrid Cells , Kinetics , Male , Mice , Models, Biological , Piperidines/pharmacology , Rats , Rats, Wistar , Serotonin/pharmacology , Serotonin Agents/pharmacology , Tritium , Verapamil/pharmacology
8.
Neuropharmacology ; 49(4): 431-8, 2005 Sep.
Article in English | MEDLINE | ID: mdl-15913670

ABSTRACT

Heterogeneous binding interactions of cerebellar GABA(A) receptors were investigated with GABA agonists and neurosteroids. GABA(A) receptors of rat cerebellum were labelled with [(3)H]ethynylbicycloorthobenzoate (EBOB), a convulsant radioligand. Saturation analysis revealed a homogenous, nanomolar population of [(3)H]EBOB binding. Both GABA and 5alpha-tetrahydrodeoxycorticosterone (5alpha-THDOC) displaced [(3)H]EBOB binding heterogeneously, with nanomolar and micromolar potencies. The nanomolar phase of displacement by GABA was selectively abolished by 100 microM furosemide. Physiological concentrations of allopregnanolone (8 nM) and 5alpha-THDOC (20 nM) increased the displacing effects of nanomolar GABA. GABA (0.3 microM ) and 5alpha-THDOC (0.3 microM ) potentiated the micromolar population of displacement by the other. Taurine inhibited [(3)H]EBOB binding also heterogeneously, with micromolar and millimolar potencies, and 0.3 microM 5alpha-THDOC potentiated this inhibition. 5beta-THDOC did not affect [(3)H]EBOB binding significantly but in 1 microM it antagonised selectively the nanomolar displacement by 5alpha-THDOC. [(3)H]EBOB binding to hippocampal GABA(A) receptors was inhibited by GABA and allopregnanolone with low (micromolar) potencies and with slope values higher than unity referring to allosteric interaction. High affinity displacement of cerebellar [(3)H]EBOB binding by GABA agonists and neurosteroids can be associated with constitutively open alpha(6)betadelta GABA(A) receptors, tonic GABAergic inhibitory neurotransmission and its modulation by physiological concentrations of neurosteroids.


Subject(s)
Bridged Bicyclo Compounds, Heterocyclic/pharmacokinetics , Cerebellum/metabolism , GABA Agonists/pharmacology , Pregnanolone/pharmacology , Receptors, GABA-A/metabolism , Animals , Anti-Anxiety Agents/pharmacology , Binding, Competitive/drug effects , Cerebellum/drug effects , Desoxycorticosterone/analogs & derivatives , Desoxycorticosterone/pharmacology , Dose-Response Relationship, Drug , Drug Interactions , Hippocampus/drug effects , Male , Protein Binding/drug effects , Radioligand Assay/methods , Rats , Rats, Wistar , gamma-Aminobutyric Acid/pharmacology
9.
J Med Chem ; 47(25): 6384-91, 2004 Dec 02.
Article in English | MEDLINE | ID: mdl-15566307

ABSTRACT

Twenty esters of 3 alpha- and 3beta-hydroxy(nor)tropanes and two amides of 3 alpha-aminotropane were prepared with substituted benzoic acids. These (nor)tropeines inhibited [(3)H]strychnine binding to glycine receptors in synaptosomal membranes of rat spinal cord. A ternary allosteric model was applied to determine the dissociation constants (K(A)) of the tropeines having strong negative cooperativities with [(3)H]strychnine binding (alpha > 10). K(A) values about 10 nM are well below those of known allosteric agents. Low concentrations (0.1K(A)) of the (nor)tropeines potentiated the displacing effects of glycine. Positive cooperativity with glycine (beta < 1) decreased with the increase in concentration and binding affinity of tropeines. Displacing potencies were also measured for [(3)H]granisetron binding to 5-HT(3) type serotonin receptors of rat cerebral cortex. Selectivities to glycine receptors versus 5-HT(3) receptors varied within 4 orders of magnitude. Nortropeines might serve as a lead to high-affinity selective allosteric modulators of glycine receptors.


Subject(s)
Amides/chemical synthesis , Receptors, Glycine/metabolism , Tropanes/chemical synthesis , Allosteric Regulation , Amides/chemistry , Amides/pharmacology , Animals , Benzoates/chemistry , Binding, Competitive , Glycine/metabolism , In Vitro Techniques , Male , Models, Molecular , Rats , Rats, Wistar , Receptors, Serotonin, 5-HT3/metabolism , Spinal Cord/drug effects , Spinal Cord/metabolism , Structure-Activity Relationship , Strychnine/metabolism , Tropanes/chemistry , Tropanes/pharmacology
10.
Neurochem Int ; 44(7): 521-7, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15209420

ABSTRACT

Allosteric modulation of [3H]strychnine binding to glycine receptors (GlyRs) was examined in synaptosomal membranes of rat spinal cord. An allosteric model enabled us to determine the cooperativity factors of the allosteric agents with [3H]strychnine and glycine bindings (alpha and beta, respectively). We modified the allosteric model with a slope factor because the slope values of the displacement curves of partial agonists (beta-alanine, taurine and gamma-aminobutyric acid) were beyond unity. The slope factor was reduced only by 100 microM propofol. Further, propofol showed positive cooperativity (beta < 1) stronger with taurine than with glycine. The extent of the positive cooperativity of propofol was nearly independent from the potencies and structures of partial agonists. The steroidal alphaxalone and minaxolone also potentiated taurine better than glycine. Alphaxalone exerted weak negative cooperativity with [3H]strychnine binding. Displacement by taurine is attenuated by granisetron and m-chlorophenylbiguanide representing negative cooperativity (beta >> 1) greater than with glycine. The results suggest a developmental role of elevated perinatal levels of taurine and neurosteroids as well as a better allosteric modulation of decreased agonist efficacies for impaired glycine receptor-ionophores.


Subject(s)
Glycine Agents/pharmacology , Receptors, Glycine/agonists , Alanine/chemistry , Alanine/pharmacology , Algorithms , Anesthetics, Intravenous , Animals , Binding, Competitive/drug effects , Drug Synergism , Glycine Agents/chemistry , In Vitro Techniques , Male , Propofol/pharmacology , Rats , Spinal Cord/drug effects , Spinal Cord/metabolism , Stereoisomerism , Strychnine/pharmacology , Taurine/chemistry , Taurine/pharmacology , Zinc/pharmacology , gamma-Aminobutyric Acid/chemistry , gamma-Aminobutyric Acid/pharmacology
11.
Eur J Pharmacol ; 483(2-3): 229-32, 2004 Jan 12.
Article in English | MEDLINE | ID: mdl-14729111

ABSTRACT

The kinetics of [3H]N-methylscopolamine binding to membranes of Chinese hamster ovary (CHO) cells expressing muscarinic M(1)-M(4) acetylcholine receptors was studied. [3H]N-methylscopolamine dissociation was used for the "single-point" analysis of allosteric modulation by vinburnine (L-eburnamonine). [3H]N-methylscopolamine dissociation was decelerated by vinburnine with EC(50) values of 29.5, 4.1, 9.5 and 15.0 microM for muscarinic M(1)-M(4) receptors, respectively. Acetylcholine doubled the EC(50) of vinburnine for muscarinic M(3) receptors. These kinetic EC(50) values correlated with equilibrium binding constants, supporting the ternary allosteric model. Vinburnine also decelerated the association of [3H]N-methylscopolamine binding, resulting in opposite cooperativity for muscarinic M(1) and M(2) receptors.


Subject(s)
N-Methylscopolamine/metabolism , Receptors, Muscarinic/metabolism , Recombinant Proteins/metabolism , Vinca Alkaloids/pharmacology , Allosteric Regulation/drug effects , Allosteric Regulation/physiology , Animals , CHO Cells , Cricetinae , Humans , N-Methylscopolamine/antagonists & inhibitors , Protein Binding/drug effects , Protein Binding/physiology , Receptor, Muscarinic M1/metabolism , Receptor, Muscarinic M2/metabolism , Receptor, Muscarinic M3/metabolism , Receptor, Muscarinic M4/metabolism , Tritium/metabolism
12.
Neuropharmacology ; 43(7): 1087-98, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12504915

ABSTRACT

Glycine receptors (GlyRs) were studied via [(3)H]strychnine binding to synaptosomal membranes of rat spinal cord. A ternary allosteric model was applied for the effects of tropeines, alcohols, minaxolone, nitrendipine, Zn(2+), muscarinic and serotonin receptor ligands. It enabled us to determine the dissociation constants of the allosteric agents (K(A)) and their cooperativity factors affecting the dissociation constants of [(3)H]strychnine (alphaK(S)) and glycine (betaK(L)). Cooperativity with [(3)H]strychnine ranged from strong negative for tropeines to weak positive for nitrendipine. Displacement curves of glycine were examined in the presence of allosteric agents. Positive cooperativities with glycine were found for submicromolar concentrations of tropisetron, bemesetron, zatosetron and nitrendipine; for tubocurarine, propofol, butanol, minaxolone, cocaine and 10 microM Zn(2+). Micromolar concentrations of tropisetron and nitrendipine showed weaker cooperativities. Other allosteric agents and 1 mM Zn(2+) displayed negative cooperativity with glycine. Binding parameters K(A) and beta correlate excellently with the activities of the allosteric agents on GlyR-ionophores. Combined inhibitory effects of the allosteric agents suggest that there are different subgroups (tropeines, alcohols and dihydropyridines) binding to distinct sites on GlyRs exerting cooperativity with glycine via a common mechanism. This is the first quantitative analysis of allosteric binding interactions for GlyRs.


Subject(s)
Receptors, Glycine/metabolism , Allosteric Regulation/physiology , Animals , Binding Sites/physiology , Dose-Response Relationship, Drug , Glycine/chemistry , Glycine/metabolism , Male , Rats , Rats, Wistar , Receptors, Glycine/antagonists & inhibitors , Spinal Cord/metabolism , Strychnine/chemistry , Strychnine/metabolism
13.
Biochem Pharmacol ; 64(2): 285-8, 2002 Jul 15.
Article in English | MEDLINE | ID: mdl-12123749

ABSTRACT

[(3)H]Strychnine binding was studied to recombinant human alpha(1) and the hyperekplexia mutant alpha(1)R271L glycine receptors (GlyRs) transiently expressed in human embryonic kidney (HEK)-293 cell cultures at 0, 18 and 37 degrees. The alpha(1)R271L mutation did not affect the linear van't Hoff plots of the exothermic binding of the antagonist [3H]strychnine while it turned taurine into an antagonist with exothermic binding. The inhibition constants of the agonist glycine showed opposite temperature dependence on alpha(1) GlyRs, corresponding to endothermic binding driven by large entropic increases. The temperature dependence of displacement by the partial agonists taurine on alpha(1) GlyRs and glycine on alpha(1)R271L GlyRs was biphasic reflecting negative heat capacity changes, dehydration changes and/or a complex binding mechanism. The thermodynamic discrimination of efficacy is valid for native rat spinal and recombinant human GlyRs. The alpha(1)R271L mutation impairs the transduction mechanism and distorts gating of GlyRs. Thereby it reduces the potency and efficacy of agonists and affects their thermodynamic parameters of binding. The hyperekplexia mutation offers a model system to demonstrate the correlation among pathophysiology, gating efficacy and binding thermodynamics of GlyRs.


Subject(s)
Glycine/metabolism , Receptors, Glycine/metabolism , Taurine/metabolism , Amino Acid Motifs , Arginine/genetics , Arginine/metabolism , Cells, Cultured , Glycine Agents/pharmacology , Humans , Leucine/genetics , Leucine/metabolism , Mutation , Receptors, Glycine/genetics , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Strychnine/pharmacology , Thermodynamics , Transfection
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