The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Mario Grassi - One of the best experts on this subject based on the ideXlab platform.
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guar gum borax hydrogel rheological low field nmr and release characterizations
Express Polymer Letters, 2013Co-Authors: Tommasina Coviello, Pietro Matricardi, Franco Alhaique, Rossella Farra, G Tesei, Simona Maria Fiorentino, Fioretta Asaro, Gesmi Milcovich, Mario GrassiAbstract:Guar gum (GG) and Guar gum/borax (GGb) hydrogels are studied by means of rheology, Low Field Nuclear Magnetic Resonance (LF NMR) and model drug release tests. These three approaches are used to estimate the mesh size (!) of the polymeric network. A comparison with similar Scleroglucan systems is carried out. In the case of GGb, the rheolog- ical and Low Field NMR estimations of ! lead to comparable results, while the drug release approach seems to underesti- mate !. Such discrepancy is attributed to the viscous effect of some polymeric chains that, although bound to the network to one end, can freely fluctuate among meshes. The viscous drag exerted by these chains slows down drug diffusion through the polymeric network. A proof for this hypothesis is given by the case of Scleroglucan gel, where the viscous contribution is not so significant and a good agreement between the rheological and release test approaches was found.
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Guar gum/borax hydrogel: Rheological, low field NMR and release characterizations
'Department of Polymer Engineering Scientific Society of Mechanical Engineering', 2013Co-Authors: Tommasina Coviello, Pietro Matricardi, Franco Alhaique, Rossella Farra, G Tesei, Fioretta Asaro, Gesmi Milcovich, S. Fiorentino, Mario GrassiAbstract:Guar gum (GG) and Guar gum/borax (GGb) hydrogels are studied by means of rheology, Low Field Nuclear Magnetic Resonance (LF NMR) and model drug release tests. These three approaches are used to estimate the mesh size (ξ) of the polymeric network. A comparison with similar Scleroglucan systems is carried out. In the case of GGb, the rheological and Low Field NMR estimations of ξ lead to comparable results, while the drug release approach seems to underestimate ξ. Such discrepancy is attributed to the viscous effect of some polymeric chains that, although bound to the network to one end, can freely fluctuate among meshes. The viscous drag exerted by these chains slows down drug diffusion through the polymeric network. A proof for this hypothesis is given by the case of Scleroglucan gel, where the viscous contribution is not so significant and a good agreement between the rheological and release test approaches was found. © BME-PT
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Guar gum/borax hydrogel: Rheological, low field NMR and release characterizations
Budapest University of Technology, 2013Co-Authors: Mario Grassi, Tommasina Coviello, Pietro Matricardi, Franco Alhaique, Rossella Farra, G Tesei, Fioretta Asaro, S. Fiorentino, Gesmi MilcovichAbstract:Guar gum (GG) and Guar gum/borax (GGb) hydrogels are studied by means of rheology, Low Field Nuclear Magnetic Resonance (LF NMR) and model drug release tests. These three approaches are used to estimate the mesh size (ζ) of the polymeric network. A comparison with similar Scleroglucan systems is carried out. In the case of GGb, the rheological and Low Field NMR estimations of ζ lead to comparable results, while the drug release approach seems to underestimate ζ. Such discrepancy is attributed to the viscous effect of some polymeric chains that, although bound to the network to one end, can freely fluctuate among meshes. The viscous drag exerted by these chains slows down drug diffusion through the polymeric network. A proof for this hypothesis is given by the case of Scleroglucan gel, where the viscous contribution is not so significant and a good agreement between the rheological and release test approaches was found
Tommasina Coviello - One of the best experts on this subject based on the ideXlab platform.
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guar gum borax hydrogel rheological low field nmr and release characterizations
Express Polymer Letters, 2013Co-Authors: Tommasina Coviello, Pietro Matricardi, Franco Alhaique, Rossella Farra, G Tesei, Simona Maria Fiorentino, Fioretta Asaro, Gesmi Milcovich, Mario GrassiAbstract:Guar gum (GG) and Guar gum/borax (GGb) hydrogels are studied by means of rheology, Low Field Nuclear Magnetic Resonance (LF NMR) and model drug release tests. These three approaches are used to estimate the mesh size (!) of the polymeric network. A comparison with similar Scleroglucan systems is carried out. In the case of GGb, the rheolog- ical and Low Field NMR estimations of ! lead to comparable results, while the drug release approach seems to underesti- mate !. Such discrepancy is attributed to the viscous effect of some polymeric chains that, although bound to the network to one end, can freely fluctuate among meshes. The viscous drag exerted by these chains slows down drug diffusion through the polymeric network. A proof for this hypothesis is given by the case of Scleroglucan gel, where the viscous contribution is not so significant and a good agreement between the rheological and release test approaches was found.
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Guar gum/borax hydrogel: Rheological, low field NMR and release characterizations
'Department of Polymer Engineering Scientific Society of Mechanical Engineering', 2013Co-Authors: Tommasina Coviello, Pietro Matricardi, Franco Alhaique, Rossella Farra, G Tesei, Fioretta Asaro, Gesmi Milcovich, S. Fiorentino, Mario GrassiAbstract:Guar gum (GG) and Guar gum/borax (GGb) hydrogels are studied by means of rheology, Low Field Nuclear Magnetic Resonance (LF NMR) and model drug release tests. These three approaches are used to estimate the mesh size (ξ) of the polymeric network. A comparison with similar Scleroglucan systems is carried out. In the case of GGb, the rheological and Low Field NMR estimations of ξ lead to comparable results, while the drug release approach seems to underestimate ξ. Such discrepancy is attributed to the viscous effect of some polymeric chains that, although bound to the network to one end, can freely fluctuate among meshes. The viscous drag exerted by these chains slows down drug diffusion through the polymeric network. A proof for this hypothesis is given by the case of Scleroglucan gel, where the viscous contribution is not so significant and a good agreement between the rheological and release test approaches was found. © BME-PT
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Guar gum/borax hydrogel: Rheological, low field NMR and release characterizations
Budapest University of Technology, 2013Co-Authors: Mario Grassi, Tommasina Coviello, Pietro Matricardi, Franco Alhaique, Rossella Farra, G Tesei, Fioretta Asaro, S. Fiorentino, Gesmi MilcovichAbstract:Guar gum (GG) and Guar gum/borax (GGb) hydrogels are studied by means of rheology, Low Field Nuclear Magnetic Resonance (LF NMR) and model drug release tests. These three approaches are used to estimate the mesh size (ζ) of the polymeric network. A comparison with similar Scleroglucan systems is carried out. In the case of GGb, the rheological and Low Field NMR estimations of ζ lead to comparable results, while the drug release approach seems to underestimate ζ. Such discrepancy is attributed to the viscous effect of some polymeric chains that, although bound to the network to one end, can freely fluctuate among meshes. The viscous drag exerted by these chains slows down drug diffusion through the polymeric network. A proof for this hypothesis is given by the case of Scleroglucan gel, where the viscous contribution is not so significant and a good agreement between the rheological and release test approaches was found
Gesmi Milcovich - One of the best experts on this subject based on the ideXlab platform.
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guar gum borax hydrogel rheological low field nmr and release characterizations
Express Polymer Letters, 2013Co-Authors: Tommasina Coviello, Pietro Matricardi, Franco Alhaique, Rossella Farra, G Tesei, Simona Maria Fiorentino, Fioretta Asaro, Gesmi Milcovich, Mario GrassiAbstract:Guar gum (GG) and Guar gum/borax (GGb) hydrogels are studied by means of rheology, Low Field Nuclear Magnetic Resonance (LF NMR) and model drug release tests. These three approaches are used to estimate the mesh size (!) of the polymeric network. A comparison with similar Scleroglucan systems is carried out. In the case of GGb, the rheolog- ical and Low Field NMR estimations of ! lead to comparable results, while the drug release approach seems to underesti- mate !. Such discrepancy is attributed to the viscous effect of some polymeric chains that, although bound to the network to one end, can freely fluctuate among meshes. The viscous drag exerted by these chains slows down drug diffusion through the polymeric network. A proof for this hypothesis is given by the case of Scleroglucan gel, where the viscous contribution is not so significant and a good agreement between the rheological and release test approaches was found.
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Guar gum/borax hydrogel: Rheological, low field NMR and release characterizations
'Department of Polymer Engineering Scientific Society of Mechanical Engineering', 2013Co-Authors: Tommasina Coviello, Pietro Matricardi, Franco Alhaique, Rossella Farra, G Tesei, Fioretta Asaro, Gesmi Milcovich, S. Fiorentino, Mario GrassiAbstract:Guar gum (GG) and Guar gum/borax (GGb) hydrogels are studied by means of rheology, Low Field Nuclear Magnetic Resonance (LF NMR) and model drug release tests. These three approaches are used to estimate the mesh size (ξ) of the polymeric network. A comparison with similar Scleroglucan systems is carried out. In the case of GGb, the rheological and Low Field NMR estimations of ξ lead to comparable results, while the drug release approach seems to underestimate ξ. Such discrepancy is attributed to the viscous effect of some polymeric chains that, although bound to the network to one end, can freely fluctuate among meshes. The viscous drag exerted by these chains slows down drug diffusion through the polymeric network. A proof for this hypothesis is given by the case of Scleroglucan gel, where the viscous contribution is not so significant and a good agreement between the rheological and release test approaches was found. © BME-PT
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Guar gum/borax hydrogel: Rheological, low field NMR and release characterizations
Budapest University of Technology, 2013Co-Authors: Mario Grassi, Tommasina Coviello, Pietro Matricardi, Franco Alhaique, Rossella Farra, G Tesei, Fioretta Asaro, S. Fiorentino, Gesmi MilcovichAbstract:Guar gum (GG) and Guar gum/borax (GGb) hydrogels are studied by means of rheology, Low Field Nuclear Magnetic Resonance (LF NMR) and model drug release tests. These three approaches are used to estimate the mesh size (ζ) of the polymeric network. A comparison with similar Scleroglucan systems is carried out. In the case of GGb, the rheological and Low Field NMR estimations of ζ lead to comparable results, while the drug release approach seems to underestimate ζ. Such discrepancy is attributed to the viscous effect of some polymeric chains that, although bound to the network to one end, can freely fluctuate among meshes. The viscous drag exerted by these chains slows down drug diffusion through the polymeric network. A proof for this hypothesis is given by the case of Scleroglucan gel, where the viscous contribution is not so significant and a good agreement between the rheological and release test approaches was found
Michael Schroeder - One of the best experts on this subject based on the ideXlab platform.
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drug repositioning or target repositioning a structural perspective of drug target indication relationship for available repurposed drugs
Computational and structural biotechnology journal, 2020Co-Authors: Daniele Parisi, Melissa F Adasme, Anastasia Sveshnikova, Sarah Naomi Bolz, Yves Moreau, Michael SchroederAbstract:Drug repositioning aims to find new indications for existing drugs in order to reduce drug development cost and time. Currently,there are numerous stories of successful drug repositioning that have been reported and many repurposed drugs are already available on the market. Although drug repositioning is often a product of serendipity, repositioning opportunities can be uncovered systematically. There are three systematic approaches to drug repositioning: disease-centric approach, target-centric and drug-centric. Disease-centric approaches identify close relationships between an old and a new indication. A target-centric approach links a known target and its established drug to a new indication. Lastly, a drug-centric approach connects a known drug to a new target and its associated indication. These three approaches differ in their potential and their limitations, but above all else, in the required start information and computing power. This raises the question of which approach prevails in current drug discovery and what that implies for future developments. To address this question, we systematically evaluated over 100 drugs, 200 target structures and over 300 indications from the Drug Repositioning Database. Each analyzed case was classified as one of the three repositioning approaches. For the majority of cases (more than 60%) the disease-centric definition was assigned. Almost 30% of the cases were classified as target-centric and less than 10% as drug-centric approaches. We concluded that, despite the use of umbrella term "drug" repositioning, disease- and target-centric approaches have dominated the field until now. We propose the use of drug-centric approaches while discussing reasons, such as structure-based repositioning techniques, to exploit the full potential of drug-target-disease connections.
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drug repositoning or target repositioning a structural perspective of drug target indication relationship for available repurposed drugs
bioRxiv, 2019Co-Authors: Daniele Parisi, Melissa F Adasme, Anastasia Sveshnikova, Yves Moreau, Michael SchroederAbstract:Drug repositioning aims to find new indications for existing drugs, in order to reduce drug development cost and time. Currently, numerous successful stories of drug repositioning have been reported and many drugs are already available on the market. Although many of those cases are products of serendipitous findings, repositioning opportunities can be uncovered systematically by following either a disease-centric approach, as a result of a close relation between an old and new indication, a target-centric one, which links a known target and its established drug to a new indication, or a drug-centric approach, which connects a known drug to a new target and its associated indication. The three approaches differ in their complexity, potential, and limits, and most important the necessary starting information and computational power. Which one is predominant in current drug repositioning and what does this imply for future developments? To address these questions, we systematically evaluated over 100 drugs, 200 targets structures and over 300 indications from the Drug Repositioning Database. Each of the analysed cases has been classified based on one of the three repositioning approaches, showing that the majority, more than 60%, falls within the disease-centric definition, around 30% within the target-centric, and only less than 10% within the drug-centric. We therefore concluded that so far repositioning has mainly been disease and target repositioning and not, as drug repositioning, as expected by definition. We discuss the reasons and suggest directions to exploit the full potential of techniques useful for drug-centric in order to sustain future rationale repositioning pipelines.
Ying Zhang - One of the best experts on this subject based on the ideXlab platform.
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a drug combination screen identifies drugs active against amoxicillin induced round bodies of in vitro borrelia burgdorferi persisters from an fda drug library
Frontiers in Microbiology, 2016Co-Authors: Jie Feng, Wanliang Shi, Shuo Zhang, David J Sullivan, Paul G Auwaerter, Ying ZhangAbstract:Although currently recommended antibiotics for Lyme disease such as doxycycline or amoxicillin cure the majority of the patients, about 10-20% of patients treated for Lyme disease may experience lingering symptoms including fatigue, pain, or joint and muscle aches. Under stress conditions such as starvation or antibiotic exposure, Borrelia burgdorferi can develop round body forms, which are a type of persister bacteria that are not killed by current Lyme antibiotics. To identify more effective drugs that are active against the round bodies of B. burgdorferi, we established a round body persister model induced by amoxicillin and screened the Food and Drug Administration (FDA) drug library consisting of 1581 drug compounds and also 22 drug combinations using the SYBR Green I/propidium iodide (PI) viability assay. We identified 23 drug candidates that have higher activity against the round bodies of B. burgdorferi than either amoxicillin or doxycycline. Eleven of these scored better than metronidazole and tinidazole which have been previously described to be active against round bodies. While some drug candidates such as daptomycin and clofazimine overlapped with a previous screen against stationary phase B. burgdorferi persisters, additional drug candidates active against round bodies we identified include artemisinin, ciprofloxacin, nifuroxime, fosfomycin, chlortetracycline, sulfacetamide, sulfamethoxypyridazine and sulfathiozole. Two triple drug combinations had the highest activity against round bodies and stationary phase B. burgdorferi persisters: artemisinin/cefoperazone/doxycycline and sulfachlorpyridazine/daptomycin/doxycycline. These findings confirm and extend previous findings that certain drug combinations have superior activity against B. burgdorferi persisters in vitro, even if pre-treated with amoxicillin. These findings may have implications for improved treatment of Lyme disease.
