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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

The effects of cyclic guanosine 3', 5'-monophosphate analog on protein accumulation in adult rat cardiomyocytes in vitro /

Li, Ying, 1972, Mar. 31- January 2007 (has links)
No description available.
82

Mechanism-Based Peptidic and Peptidomimetic Human Sirtuin Inhibitors

Hirsch, Brett M. 21 April 2011 (has links)
No description available.
83

Coordination of Chemistry of Re(I) Carbonyl Complexes as Pharmaceutically Important Compounds and Synthesis, Characterization, and Metalation of Novel Phthalocyanine Analogs

Costa, Wijeendra M. R. S. 21 April 2011 (has links)
No description available.
84

Randy Akrofi MS Thesis

Randy Akrofi (15342217) 29 April 2023 (has links)
<p>  </p> <p>Quinolines are benzopyridine complexes present in many modern antimalarial, anticancer, anti-inflammatory, antimicrobial, and other useful pharmaceuticals and natural products.1,2 Quinolines form the scaffold for many potent anticancer drugs; this is because quinolines can undergo both nucleophilic and electrophilic substitution reactions, can be ingested and inhaled by humans without any harm, and possess a great deal of biological importance.3 My research has focused on synthesizing 3H-pyrazolo[4,3-f]quinoline analogs. The 3H-pyrazolo[4,3-f]quinoline scaffold was modified using various amine groups to obtain amide analogs as well as see how a change in the scaffold affects the anticancer activity of the synthesized complexes by screening them against kinases such as FLT3, CDK2, CDK4, and CDK9 to see if they are effective inhibitors. The synthesized complexes were then characterized using proton, carbon NMR and FTIR spectroscopy.</p>
85

Synthesis of electric networks interconnecting PZT actuators to efficiently damp mechanical vibrations

Porfiri, Maurizio 16 January 2001 (has links)
The aim of this thesis is to show that it is possible to damp mechanical vibrations in a given frame, constituted by Euler beam governed by the equations of an elastica, by means of piezoelectric actuators glued on every beam and interconnected each other via electrical networks.Since we believe that the most efficient way to damp mechanical vibrations by means of electrical networks, is to realize a strong modal coupling between the electrical and the mechanical motion, we will synthesize a distributed circuit analog to the Euler beam.We will approach this synthesis problem following the black box approach to mechanical systems, studied by many engineers and scientists during the 1940's in an attempt to design analog computers.It will be shown that it is possible to obtain a quick energy exchange between its mechanical and electrical forms, using available piezoelectric actuators.Finally we will study a numerical simulation for the damping of transverse vibrations of a beam clamped at both ends. / Master of Science
86

OXAZOLIDINONES AS A PRIVILEGED SCAFFOLD AND PRELIMINARY EVALUATION

Day, Brian M. January 2022 (has links)
Drug discovery contains many strategies, one of which is the privileged scaffold strategy. This strategy incorporates a similar molecular framework within a collection of drug-like compounds in order to target various receptors. These scaffolds are useful to drug discovery scientists since they assist in developing libraries as well as demonstrating selectivity to a target. Oxazolidinones are 5-membered heterocyclic compound containing an oxygen, a nitrogen, and a carbonyl within the ring system. In this present study, the oxazolidinone structure was utilized as a privileged scaffold to target serotonin receptor 7 (5-HT7), mutated BRAF kinase (BRAFV6000E), Bruton’s tyrosine kinase (BTK), and Cyclin-dependent protein kinase 4 and 6 (CDK4/6). Aryl piperazines and piperidines were integrated as another privileged scaffold to support the selectivity towards 5-HT7, while aminopyrimidines were employed to increase binding against the kinases. The 5-HT7 oxazolidinone series was successfully synthesized and analyzed against 5-HT7; however, the three kinase oxazolidinone series were not successfully synthesized.Candidemia is the most common bloodstream infection in the U.S. and is associated with high patient mortality rates. Due to prolonged and/or repeated clinical use of current antifungal agents, drug-resistant fungi have become an emerging problem. There is a need for new antifungals to assist in overcoming drug resistant fungi. In the second project outlined in this work, a series of ketoconazole analogs were designed and successfully synthesized. The ketoconazole analogs exhibited antifungal activity; however, no clear trends were observed in this series. Overall, the series exhibited less CYP3A4 inhibition than the parent compound, ketoconazole. / Pharmaceutical Sciences
87

Automated fabrication of cell-instructive synthetic sulfonated and sulfated hydrogels

Siedel, Anna Charlott 14 February 2024 (has links)
The extracellular matrix (ECM) is the highly hydrated, protein- and glycosaminoglycan- (GAG) based cell environment that provides cell-instructive cues like the mechanical stabilization of the cells and transmission of biochemical and physical signals. To biochemically and mechanically mimic the ECM, hydrogels with the highly negatively charged GAG heparin in interplay with a stabilizing polymer network are of high interest in biomaterial engineering. The application as cell-instructive materials allows for controlling transport processes of signaling molecules within the matrices, cell growth and differentiation behavior, and cellular fate decisions. In particular, heparin-based biomaterials enable targeted sequestration of signaling molecules on the one hand, but also sustained delivery of them with a lower necessary amount to be used, in contrast to the discontinuous application of solutes. In addition, heparin-based biomaterials can protect the loaded cargo from enzymatic degradation and conformational changes.[1]–[3] The affinity to signaling molecules as key feature provides the potential for applications in wound healing and tissue regeneration. Synthetic sulfonated polymers (SSPs) as synthetic heparin analogs can address multiple drawbacks of native heparin, such as its heterogeneous chemical structure and the potential risk of viral contamination from the animal isolation source.[4],[5] Due to a large number of molecular design opportunities in particular the degree of sulfation, sulfate volume concentration, sulfate or sulfonate nature, distance of the sulf(on)ate from the backbone, and hydrophobicity of the polymers, biochemical processes may be controlled in a targeted manner. The chemical possibilities for forming a hydrogel network based on SSPs are far more diverse with synthetic, freely designable polymers to achieve a targeted structure and chemical nature of the network. Here, the aim was to introduce a library of SSPs to replace heparin in fully synthetic hydrogels capable of modulating cell-instructive cues such as soluble factor signaling, adhesiveness, and growth behavior of integrated cells. Accordingly, a library of systematically varied SSPs differing in degree of sulfation, sulfate or sulfonate conjugation, hydrophobicity, and sulf(on)ate distance to the backbone have been synthesized from by polymer analog reaction of various sulf(on)ated amines with a polyacrylate (15 kDa, sodium salt) as the polymeric backbone. The polymers have been thoroughly characterized by proton nuclear magnetic resonance (1H-NMR), Fourier-transform infrared spectroscopy (FTIR), asymmetric flow field flow fractionation (AF4) coupled light scattering analysis, and microscale thermophoresis (MST) for their molecular composition, stability in aqueous solution, conformation, and interaction with a chosen signal molecule. The affinity of the very stable coiled polymers under physiological conditions to signaling molecules depends mainly on the degree of sulfation, sulfate or sulfonate nature, and hydrophobicity. The SSPs are crosslinked with 4-arm star-shaped poly(ethylene glycol) (starPEG) either directly to form amide-crosslinked hydrogels or by pre-functionalization via Michael-type addition to prepare cell-instructive hydrogels, each with graded mechanical properties. The affinity of these hydrogels for various signaling molecules can be quantified compared to heparin-based ones and attributed to the influence of the degree of sulfation, sulfate volume concentration, sulfate or sulfonate nature, and hydrophobicity. The potential of SSPs in functional 3D tissue cultures could be confirmed by renal morphogenesis and neural network formation in the corresponding hydrogels by collaborators. Further on, the synthesis procedure of hydrogel precursors has been transferred to fully automated procedures. Because standardized production of cell-instructive hydrogels at low compositional and batch-to-batch variation and material compliance can benefit from high-throughput synthesis and liquid handling robots. An automated multistage workflow was developed to synthesize hydrogel precursors, carry out hydrogel formation, and execute cell culture experiments with cells embedded in the hydrogels. The protocol combines two robotic liquid handling systems and a microscope for automated sample imaging and cell analysis. The customized heparin and SSP maleimidation procedures, including temperature-regulated synthesis, purification, and aliquotation, were implemented on a customized liquid-handling robot. The resulting hydrogel precursors were analyzed for their maleimide conjugation efficiency and purity by 1H-NMR and conductivity measurements and for their hydrogel formation ability. This automated synthesis can ensure the quality and production of good manufacturing practice (GMP)-compliant hydrogel materials. Automated SSP hydrogel preparation, cell culture, and analysis can further promote combinatorial approaches to biomedical applications of cell-instructive materials. References [1] Lohmann, N.; Schirmer, L.; Atallah, P.; Wandel, E.; Ferrer, R. A.; Werner, C et al. Glycosaminoglycan-Based Hydrogels Capture Inflammatory Chemokines and Rescue Defective Wound Healing in Mice. Sci. Transl. Med. 2017, 9 (386), 1–12. [2] Schirmer, L.; Atallah, P.; Werner, C.; Freudenberg, U. StarPEG-Heparin Hydrogels to Protect and Sustainably Deliver IL-4. Adv. Healthc. Mater. 2016, 5 (24), 3157–3164. [3] Liang, Y.; Kiick, K. L. Heparin-Functionalized Polymeric Biomaterials in Tissue Engineering and Drug Delivery Applications. Acta Biomater. 2014, 10 (4), 1588–1600. [4] Blossom, D. B.; Kallen, A. J.; Patel, P. R.; Elward, A.; Robinson, L.; Gao, G. et al. Outbreak of Adverse Reactions Associated with Contaminated Heparin. N. Engl. J. Med. 2008, 359 (25), 2674–2684. [5] Hirsh, J.; Dalen, J. E.; Anderson, D. R.; Poller, L.; Bussey, H.; Ansell, J. et al. Oral Anticoagulants. Chest 1998, 114 (5), 445S-469S.
88

Synthesis and Biological Evaluation of Histone Deacetylase Inhibitor Largazole and Analogs

Bhansali, Pravin 24 August 2011 (has links)
No description available.
89

Synthesis and Design of MS-153 Analogues as Potential Drugs for Treatment ofAlcohol and Methamphetamine Co-abuse

Almalki , Atiah Hassan January 2017 (has links)
No description available.
90

Unraveling Genetically Encoded Pathways Leading to Bioactive Metabolites in Group V Cyanobacteria

Bunn, Brittney Michalle 27 January 2016 (has links)
No description available.

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