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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.
31

Production and Evaluation of a Bombesin Analogue Conjugated to the Albumin-Binding Domain and DOTA for Prostate Cancer Radiotherapy / Produktion och utvärdering av en bombesinanalog konjugerad till en albuminbindande domän och DOTA för radioterapi i prostatacancer

Landmark, Fredrika January 2021 (has links)
Prostate cancer is one of the most common types of cancer worldwide and claims hundreds of thousands of lives annually. Currently the most common treatment for prostate cancer is external beam radiotherapy, however, this treatment comes with serious side effects since it lacks selectivity for the cancer cells. Therefore, less harmful treatments are needed and sought for, such as targeted treatments that are intended to only affect cancer cells and thereby reduce the side effects. Targeted treatments require a target that differentiates the cancer cells from healthy cells. A promising target candidate that has gained attention in recent years is gastrin releasing peptide receptor (GRPR), a protein commonly overexpressed in prostate cancer cells. Furthermore, a targeting molecule intended to bind to the target is also required. For this purpose, the bombesin analogue RM26, a high affinity GRPR binder, shows promise. Previous studies have led to the development of RM26-conjugates for the purpose of targeted prostate cancer radiotherapy. In these conjugates RM26 has been linked to a DOTA-chelator for radiolabeling, and an albumin binding domain (ABD) to prolong the conjugate’s half-life in vivo by binding to human serum albumin (HSA). The idea is that the RM26-conjugate will bind to both HSA in the blood and to GRPR on the prostate cancer cells and eliminate the cancer cells with the radiation from the radionuclide attached to the DOTA-chelator. Although these earlier studied conjugates have been very promising some improvements of certain aspects need to be achieved, mainly to improve the biodistribution with retained GRPR binding affinity. Therefor the purpose of this project was to produce three new versions of previous RM26- conjugates and evaluate if they are suitable for further prostate cancer therapy studies. The three RM26-conjugates were developed with primarily recombinant expression in E. coli cells and solid phase peptide synthesis (SPPS). The characterization phase in this project was carried out with mainly five different methods: matrix-assisted laser desorption ionization time- of-flight mass spectrometry (MALDI-TOF-MS), electrospray ionization- mass spectrometry (ESI-MS), circular dichroism (CD), surface plasmon resonance (SPR) and flow cytometry. The results showed that all three new RM26-conjugates were possible to produce and yielded final products corresponding to the expected molecular weights. Furthermore, the results indicate that all three RM26-conjuagtes are stable and maintain their structural properties under in vivo- temperatures and that they have high binding affinity for HSA. Further studies need to be conducted before drawing any certain conclusions regarding GRPR binding affinity. / Prostatacancer är en av de mest vanligt förekommande cancertyperna världen över och skördar hundratusentals liv årligen. I nuläget är extern strålbehandling det vanligaste terapialternativet mot prostatacancer, men denna behandling kommer med allvarliga biverkningar på grund av att den saknar selektivitet för cancerceller. Därför finns ett stort behov av mindre skadliga behandlingsformer, såsom riktade behandlingar som endast är avsedda att påverka cancerceller och därigenom minska biverkningarna. Riktade behandlingar kräver ett mål som skiljer cancercellerna från friska celler. En lovande målkandidat som har uppmärksammats de senaste åren är gastrinfrisättande peptidreceptor (GRPR), ett protein som vanligtvis överuttrycks i prostatacancerceller. I tillägg så krävs också en målsökande molekyl avsedd att binda till målet. För detta ändamål visar bombesinanalogen RM26, en GRPR-bindare med hög affinitet, sig vara lovande. Tidigare studier har utvecklat RM26-konjugat för målinriktad strålbehandling av prostatacancer. Dessa konjugat består av en RM26-peptid bunden till en DOTA-kelator för radioinmärkning och en albuminbindande domän (ABD) för att förlänga konjugatens halveringstid in vivo genom att binda till humant serumalbumin (HSA). Syftet med RM26- konjugaten är att de ska binda till både HSA i blodet och GRPR på prostatacancercellerna, och därmed eliminera cancercellerna med strålning från den radioinmärkta DOTA-kelatorn. Även om de tidigare RM26-konjugaten har varit mycket lovande krävs det att vissa förbättringar av några aspekter uppnås, främst affiniteten för GRPR. Syftet med detta projekt var därför att producera tre nya versioner av tidigare RM26-konjugat och utvärdera ifall de uppvisar tillfredsställande egenskaper. De tre RM26-konjugaten utvecklades primärt rekombinant i E. coli-celler och fastfas- peptidsyntes (SPPS). Karaktäriseringsfasen i detta projekt genomfördes med huvudsakligen fem olika metoder: MALDI-TOF-MS, elektrosprejjonisering-masspektrometri (ESI-MS), cirkulär dikroism (CD), ytplasmonresonans (SPR) och flödescytometri. Resultaten visade att alla tre nya RM26-konjugat var möjliga att producera och gav slutprodukter motsvarande de förväntade molekylvikterna. Vidare indikerar resultaten att alla tre RM26-konjugat är stabila och bibehåller sina strukturella egenskaper under in vivo-temperaturer och att de har hög affinitet för HSA. Ytterligare studier bör utföras innan säkrare slutsatser kan dras angående GRPR-bindningsaffinitet.
32

Optimization of immunotherapeutic relevant ABD-derived affinity proteins for prolonged serum half-life

Bergström, Ebba January 2022 (has links)
Marknaden för proteinbaserade läkemedel, de så kallade biologiska läkemedlen, är idag en industri som omsätter miljarder. Ett vanligt sätt att utveckla dessa läkemedel på är med hjälp av monoklonala antikroppar då de kan binda till sitt mål med hög specificitet. Däremot begränsas denna teknik av en lång och dyr produktion som dessutom kräver däggdjursbaserade uttrycksystem. En alternativ teknik till de monoklonala antikropparna är att använda små proteiner som enkelt kan produceras i bakterier till en låg kostnad. Dock begränsas denna metod av de små proteinernas korta cirkuleringstid i blodet. I ett tidigare projekt, har ett litet protein vid namnet ABDderived affinity ProTein (ADAPT) på cirka 7 kDa, utvecklats för att kunna binda till både humant serumalbumin (HSA) för att förlänga cirkulationstiden i blodet och Interleukin 17c (IL17c) som är ett pro-inflammatorisk cytokin. Studien visade dock att ADAPT proteinet inte samtidigt kunde binda till de båda molekylerna tillräckligt effektivt. Syftet med denna uppsats är därför att undersöka om det nämnda proteinet kan optimeras genom så kallad multimering och/eller manipulering av bindningssätet för HSA i syfte att åstadkomma en effektiv och mer långvarig cirkulationstid i blodet samtidigt som det binder sig till sitt mål, IL17c. Tio nya versioner av ADAPT proteinet har utvecklats genom att klona och transformera proteiner till en högt producerande Escherichia coli (E. coli) stam. Proteinerna har sedan producerats och renats fram. Det kunde observeras att proteinerna hade den önskade renheten för att kunna karaktäriseras. Vidare var det möjligt att se att proteinerna hade sin önskade molekylvikt och erhöll sin förväntade struktur som en alfahelix. Proteinernas smältpunkter hade förbättrats eller var liknande jämfört med det ursprungliga proteinet. Dessutom kunde alla proteiner återgå till sin ursprungliga struktur efter upphettning. Utvärderingen av proteinernas bindningskapacitet, med original proteinet som referens, visade på en ökad affinitet till sitt mål, IL17c, för två dimerer och trimeren samt en jämförbar affinitet för två av monomererna med ett manipulerat bindingssäte till HSA. Interaktion till HSA var jämförbar med den ursprungliga ADAPT molekylen för alla nya varianter förutom monomererna med ett manipulerat bindingssäte och dimeren med två manipulerat bindingssäten till HSA. Evaluering av de nya proteinernas kapacitet att binda samtidigt till HSA och IL17c visade att det var gynnsamt med en dimereiserad molekyl då det skapade en distans mellan molekylerna och dess bindningssäten. Vidare kunde det också visas att ordningen som molekylerna interagerade med varandra påverkade proteinernas simultana bindning. / The market for protein-based drugs, or the so-called biopharmaceuticals, is a multibillion-dollar industry today. In the development of protein-based drugs it is common to use monoclonal antibodies (mAbs) due to their ability to bind to its target with high specificity. However, therapeutical development of mAbs is limited by its long and expensive production in mammalian expression system. An alternative to mAbs are the so-called alternative scaffolds which are small proteins that can be produced in bacteria at lower costs. Although a drawback with the latter proteins is their short serum half-life. A small scaffold protein, ABD-Derived Affinity ProTein (ADAPT) of approximate 7 kDa was earlier engineered to obtain bispecific affinity, to Human Serum Albumin (HSA), to extend its half-life, as well as to the pro-inflammatory cytokine, Interleukin 17c (IL17c). Unfortunately, it was shown that the simultaneous binding was not efficient enough for its desired purpose. The aim with this project was therefore to investigate if the previous mentioned binder could be optimized by multimerization and/or manipulation of the HSA binding site for an efficient half-life extension. By generating ten new designs of the ADAPT variants, it was observed that the new variants had stable alpha helical structures and an improved or similar melting temperature as the original variant. The evaluation of the target binding displayed an improved affinity to the target, IL17c, for two of the dimeric versions as well as for the trimer and a comparable affinity for two of the monomers with a manipulated HAS binding site. The interaction to HSA was comparable to the original ADAPT for all binders except from the monomers with impaired HSA binding and the dimer with two impaired HSA binding sites. The evaluation of the simultaneous binding showed that it was favored by dimerization when a distance between the two molecule and their binding surfaces was added. Moreover, it could also be seen that the order of binding events had an impact on the simultaneous binding.
33

Effets dynamiques et conformationnels sur le rôle de transport des albumines sériques / Dynamics and conformational effects on the transport role of serum albumins

Paris, Guillaume 05 June 2014 (has links)
L’albumine sérique humaine (HSA) est une protéine connue pour ses propriétés de transport exceptionnelles et son contenu élevé en ponts disulfure. L’étude de sa dynamique conformationnelle représente un défi important dans la compréhension de ses fonctions physiologiques. Le but de notre travail a été d’étudier cette dynamique conformationnelle et de comprendre le rôle des ponts disulfure dans le maintien de la structure native de la protéine. Notre analyse est basée sur des simulations de dynamique moléculaire couplées à des analyses par composantes principales. Outre la validation de la méthode de simulation les résultats fournissent de nouveaux éclairages sur les principaux effets de la réduction des ponts disulfure dans les albumines sériques. Les processus de dépliement/repliement protéique ont été détaillés. La prédiction de la structure réduite d’équilibre a également fait l’objet d’une attention particulière. Une étude détaillée de la dynamique conformationnelle globale de la protéine ainsi que celle des deux sites principaux de complexation a été effectuée. D’éventuels effets allostériques entre ces deux sites ont été recherchés. Les résultats théoriques obtenus ont été discutés avec les données expérimentales disponibles / Human serum albumin (HSA) is a protein known for its exceptional transport properties and its high content of disulfide bridges. The study of the conformational dynamics represents a major challenge in the comprehension of its physiological functions. The aim of our work was to study the conformational dynamics and to understand the roleof disulfide bonds in the stability of the native protein structure. Our analysis is based on simulations of molecular dynamics coupled with principal component analysis. Beyond the validation of the simulation method, the results provide new insights on the main effects of the disulfide bonds reduction in serum albumins. Protein unfolding/refolding processes were detailed. A special attention is paid to the prediction of the reduced structure at the equilibrium. A detailed study of the global protein conformational dynamics as well as the two main binding sites were performed. Possible allosteric effects between these two sites were researched. The theoretical results have been discussed with the available experimental data
34

Bioanalytical Applications of Intramolecular H-Complexes of Near Infrared Bis(Heptamethine Cyanine) Dyes

Kim, Junseok 15 July 2008 (has links)
This dissertation describes the advantages and feasibility of newly synthesized near-infrared (NIR) bis-heptamethine cyanine (BHmC) dyes for non-covalent labeling schemes. The NIR BHmCs were synthesized for biomolecule assay. The advantages of NIR BHmCs for biomolecule labeling and the instrumental advantages of the near-infrared region are also demonstrated. Chapter 1 introduces the theory and applications of dye chemistry. For bioanalysis, this chapter presents covalent and non-covalent labeling. The covalent labeling depends on the functionality of amino acids and the non-covalent labeling relies on the binding site of a protein. Due to the complicated binding process in non-covalent labeling, this chapter also discusses the binding equilibria in spectroscopic and chromatographic analyses. Chapter 2 and 3 evaluate the novel BHmCs for non-covalent labeling with human serum albumin (HSA) and report the influence of micro-environment on BHmCs. The interesting character of BHmCs in aqueous solutions is that the dyes exhibit non- or low-fluorescence compared to their monomer counterpart, RK780. It is due to their H-type closed clam-shell form in the solutions. The addition of HSA or organic solvents opens up the clam-shell form and enhances fluorescence. The binding equilibria are also examed. Chapter 4 provides a brief introduction that summaries the use of capillary electrophoresis (CE), and offers a detailed instrumentation that discusses the importance and advantage of a detector in NIR region for CE separation. Chapter 5 focuses on the use of NIR cyanine dyes with capillary electrcophoresis with near-infrared laser induce fluorescence (CE-NIR-LIF) detection. The NIR dyes with different functional groups show that RK780 is a suitable NIR dye for HSA labeling. The use of BHmCs with CE-NIR-LIF reduces signal noises that are commonly caused by the interaction between NIR cyanine dyes and negatively charged capillary wall. In addition, bovine carbonic anhydrase II (BCA II) is applied to study the influence of hydrophobicity on non-covalent labeling. Finally, chapter 6 presents the conformational dependency of BHmCs on the mobility in capillary and evaluates the further possibility of BHmCs for small molecule detection. Acridine orange (AO) is used as a sample and it breaks up the aggregate and enhances fluorescence. The inserted AO into BHmC changes the mobility in capillary, owing to the conformational changes by AO.
35

Estudo de interação dos flavonóides Isovitexina e 2-Fenilcromona com a Albumina do Soro Humano: abordagem experimental e computacional / Interaction study of flavonoids Isovitexin and 2-Phenylcromone with Human Serum Albumin: experimental and computational approach

Caruso, Ícaro Putinhon [UNESP] 26 August 2016 (has links)
Submitted by ÍCARO PUTINHON CARUSO null (ykrocaruso@hotmail.com) on 2016-09-19T16:20:38Z No. of bitstreams: 1 tese_doutorado_icaro_vf.pdf: 17027642 bytes, checksum: 71d2f869670d044aace5f2ab6326b657 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-09-22T14:26:36Z (GMT) No. of bitstreams: 1 caruso_ip_dr_sjrp.pdf: 17027642 bytes, checksum: 71d2f869670d044aace5f2ab6326b657 (MD5) / Made available in DSpace on 2016-09-22T14:26:36Z (GMT). No. of bitstreams: 1 caruso_ip_dr_sjrp.pdf: 17027642 bytes, checksum: 71d2f869670d044aace5f2ab6326b657 (MD5) Previous issue date: 2016-08-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os flavonóides fazem parte de uma ampla classe de compostos polifenólicos os quais ocorrem naturalmente nas plantas e podem ser encontrados nas sementes, caules, folhas, flores e/ou frutos. Estudos recentes indicam que esses compostos polifenólicos podem apresentar uma variedade significativa de atividades biológicas benéficas para a saúde humana, como por exemplo: antioxidante, anti-inflamatória, antibacteriana, antiviral e anticancerígena. A Albumina do Soro Humano (HSA) é a principal proteína extracelular presente no plasma sanguíneo. A função central dessa proteína é transportar e distribuir ligantes endógenos e exógenos para diferentes alvos moleculares no corpo humano. Por tais aspectos, torna-se importante o desenvolvimento de estudos que caracterizam a interação dos flavonóides com a proteína transportadora HSA. Este trabalho investiga a interação dos flavonóides Isovitexina (ISO) e 2-Fenilcromona (2PHE) com a HSA, utilizando técnicas experimentais de espectroscopia de fluorescência, absorbância UV-Vis, dicroísmo circular (CD) e infravermelho com transformada de Fourier (FT-IR); juntamente com ferramentas computacionais de cálculo {\it{ab initio}}, dinâmica molecular e modelagem molecular. A integração dessas abordagens experimentais e computacionais possibilita caracterizar a formação dos complexos HSA-flavonóides, determinando aspectos físico-químicos como: constantes de afinidade, parâmetros termodinâmicos, número de sítios de ligação, perfil de cooperatividade e resíduos de aminoácidos responsáveis pelas interações proteína-flavonóides (hidrofóbicas e eletrostáticas). / Flavonoids belong to a large class of polyphenolic compounds which occur naturally in plants and can be found seeds, stems, leaves, flowers and/or fruits. Recent studies indicate that these polyphenolic compounds can present a significant variety of beneficial biological activities on human health, such as: antioxidant, anti-inflammatory, antibacterial, antiviral, and anticancer. Human Serum Ambumin (HSA) is the main extracellular protein presents in blood plasma. The core function of this protein is to carry and distribute endogenous and exogenous ligands to different molecular targets in the human body. For these aspects, it is important to develop studies that characterize the interaction of the flavonoids with the carrier protein HSA. This work investigates the interaction of the flavonoids Isovitexin (ISO) and 2-Phenylchromone (2PHE) with the HSA, using experimental techniques of fluorescence, UV-Vis absorbance, circular dichroism (CD), and Fourier transform infrared (FT-IR) spectroscopy; along with computational tools of ab initio calculation, molecular dynamics, and molecular modeling. The integration of these experimental and computational approaches allows to characterize the formation of the HSA-flavonoids complexes, determining physicochemical aspects, sucha as: affinity constants, thermodynamic parameters, number of binding sites, cooperativity profile and aminoacid residues responsable for the protein-flavonoids interactions (hydrophobic and electrostatic).
36

Estudo in silico da intera??o da albumina de soro humano com o ibuprofeno

Dantas, Diego de Sousa 28 February 2013 (has links)
Made available in DSpace on 2014-12-17T14:10:28Z (GMT). No. of bitstreams: 1 DiegoSD_DISSERT.pdf: 4467915 bytes, checksum: 1bb0defec90e5ed329ebefbf24ac108a (MD5) Previous issue date: 2013-02-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Currently, computational methods have been increasingly used to aid in the characterization of molecular biological systems, especially when they relevant to human health. Ibuprofen is a nonsteroidal antiinflammatory or broadband use in the clinic. Once in the bloodstream, most of ibuprofen is linked to human serum albumin, the major protein of blood plasma, decreasing its bioavailability and requiring larger doses to produce its antiinflamatory action. This study aimes to characterize, through the interaction energy, how is the binding of ibuprofen to albumin and to establish what are the main amino acids and molecular interactions involved in the process. For this purpouse, it was conducted an in silico study, by using quantum mechanical calculations based on Density Functional Theory (DFT), with Generalized Gradient approximation (GGA) to describe the effects of exchange and correlation. The interaction energy of each amino acid belonging to the binding site to the ligand was calculated the using the method of molecular fragmentation with conjugated caps (MFCC). Besides energy, we calculated the distances, types of molecular interactions and atomic groups involved. The theoretical models used were satisfactory and show a more accurate description when the dielectric constant ε = 40 was used. The findings corroborate the literature in which the Sudlow site I (I-FA3) is the primary binding site and the site I-FA6 as secondary site. However, it differs in identifying the most important amino acids, which by interaction energy, in order of decreasing energy, are: Arg410, Lys414, Ser 489, Leu453 and Tyr411 to the I-Site FA3 and Leu481, Ser480, Lys351, Val482 and Arg209 to the site I-FA6. The quantification of interaction energy and description of the most important amino acids opens new avenues for studies aiming at manipulating the structure of ibuprofen, in order to decrease its interaction with albumin, and consequently increase its distribution / Na atualidade, os m?todos computacionais v?m sendo cada vez mais utilizados para auxiliar a biologia molecular na caracteriza??o de sistemas biol?gicos, principalmente quando esses possuem relev?ncia para a sa?de humana. O ibuprofeno ? um antiinflamat?rio n?o-esteroidal de larga utiliza??o na cl?nica. Uma vez na corrente sangu?nea, boa parte do ibuprofeno fica ligada a albumina de soro humano, a principal prote?na do plasma sangu?neo, diminuindo a sua biodisponibilidade e necessitando de maiores doses para a produ??o de seu efeito antiinflamat?rio. Este estudo teve por objetivo caracterizar, atrav?s da energia de intera??o, como ocorre a liga??o do ibuprofeno ? albumina e estabelecer quais os principais amino?cidos e intera??es moleculares envolvidas no processo. Para tal desenvolveu-se um estudo in silico, com utiliza??o de c?lculos de mec?nica qu?ntica, baseada na Teoria do Funcional da Densidade (DFT), com aproxima??es do Gradiente Generalizado (GGA) para descri??o dos efeitos de correla??o e troca. A energia de intera??o de cada amino?cido do s?tio de liga??o, com o ligante foi calculada com base no m?todo de fragmenta??o molecular com capas conjugadas (MFCC). Al?m da energia, foram calculadas as dist?ncias, tipos de intera??es moleculares e grupos at?micos envolvidos. Os modelos te?ricos utilizados foram satisfat?rios e demonstraram uma descri??o mais precisa com a utiliza??o da constante diel?trica ε=40. Os achados corroboram com a literatura colocando o s?tio Sudlow I (I-FA3) como o principal s?tio de liga??o e o s?tio I-FA6 como s?tio secund?rio. Contudo, difere quanto ? identifica??o dos amino?cidos mais importantes, que por meio da energia de intera??o, em ordem decrescente de energia, s?o: Arg410, Lys414, Ser 489, Leu453 e Tyr411 para o S?tio I-FA3 e Leu481, Ser480, Lys351, Val482 e Arg209 para o s?tio I-FA6. A quantifica??o da energia de intera??o e a descri??o dos amino?cidos mais importantes abre caminhos para novos estudos que visem a manipula??o da estrutura do ibuprofeno, no sentido de diminuir a intera??o desse com a albumina, e consequentemente aumentar a sua distribui??o
37

Design of New Up-conversion Systems for Anticancer Therapies

Anaya González, Cristina 19 July 2021 (has links)
[ES] El cáncer es una de las principales causas de muerte a nivel mundial. Los tratamientos anticancerígenos generalmente usados tienen diversos efectos secundarios producidos por su baja especificidad. Esta es una de las razones por las que se sigue en continua búsqueda de nuevos tratamientos. Dentro de estas nuevas investigaciones se encuentra el extenso campo de la nanomedicina, es decir, el estudio de nuevos materiales a escala nanométrica. Esta permite reducir dichos efectos secundarios aumentando la selectividad y especificidad de los tratamientos. Dentro de los nanomateriales se encuentran las nanopartículas de upconversion que son capaces de absorber luz en el infrarrojo cercano y emitirla en la región ultravioleta-visible. Por otro lado, desde el principio de la historia de la medicina la luz se ha empleado como forma de tratamiento teniendo un rol muy importante. Un inconveniente para dichos tratamientos suele ser la necesidad de emplear luz de la región ultravioleta-visible, pues las biomoléculas son capaces de absorber y produce daño celular. En este contexto, la presente Tesis Doctoral se centra en el estudio de nuevas formas de tratamiento anticancerígeno combinando nanomedicina y luz. Para ello se han desarrollado nuevos fármacos fototóxicos y nuevos materiales capaces de ser activados mediante luz infrarroja cercana. En primer lugar, se sintetizaron nuevas fluoroquinolonas para explorar sus propiedades fototóxicas para su uso en fotoquimioterapia (Capítulo 3 de la Tesis). Se estudiaron las características fotofísicas y fotoquímicas de los nuevos compuestos, además de su capacidad para producir mayor fototoxicidad en las células en comparación con las fluoroquinolonas como la lomefloxacina mediante la aplicación de luz ultravioleta. En base a los resultados obtenidos se realizó un estudio para determinar las diferencias entre las interacciones de algunas fluoroquinolonas dihalogenadas, incluidas las comentadas anteriormente, y biomoléculas como ADN y proteínas. La reactividad de sus intermedios fotogenerados también se estudió en el Capítulo 4. Tras conocer en profundidad la capacidad fototóxica de los nuevos fármacos, en el Capítulo 5 se llevó a cabo el diseño de un nanosistema compuesto por fluoroquinolonas y nanopartículas de conversión ascendente. Se demostró la alta capacidad fototóxica de este nuevo nanosistema. De esta manera, se generó actividad fototóxica a partir de una fluoroquinolona sin el uso de luz ultravioleta Por otro lado, la formación de profármacos abre la puerta a la administración selectiva de fármacos contra el cáncer. Los profármacos consisten en la unión fotolábil de una molécula capaz de ser activada por la luz y el fármaco de interés. Sin embargo, un conocimiento profundo de las propiedades fotofísicas y fotoquímicas del fotodisparador y de los potenciales redox de ambos miembros de la diada puede ser crucial para obtener la fotoliberación deseada. Así, en el Capítulo 6, se destacó la relevancia de estos datos utilizando un profármaco formado por un derivado de cumarina como molécula fotoactivable y colchicina como fármaco. Finalmente, en el Capítulo 7 se exploró la síntesis de un nuevo nanosistema que contiene un profármaco formado por un derivado de cumarina unido al fármaco contra el cáncer clorambucilo y nanopartículas biocomatibles de conversión ascendente. La adición de albúmina de suero humano como recubrimiento de las nanopartículas cumple la doble función de obtener nanopartículas biocompatibles y ser el lugar de carga del profármaco. / [CA] El càncer és una de les principals causes de mort a nivell mundial. Els tractaments anticancerígens generalment usats tenen diversos efectes secundaris produïts per la seva baixa especificitat. Aquesta és una de les raons per les que se segueix en contínua recerca de nous tractaments. Dins d'aquestes noves investigacions es troba l'extens camp de la nanomedicina, és a dir, l'estudi de nous materials a escala nanomètrica. Aquesta permet reduir aquests efectes secundaris augmentant la selectivitat i especificitat dels tractaments. Dins dels nanomaterials es troben les nanopartícules de upconversion que són capaços d'absorbir llum en l'infraroig proper i emetre-la en la regió ultraviolada-visible. D'altra banda, des del principi de la història de la medicina la llum s'ha emprat com a forma de tractament tenint un paper molt important. Un inconvenient per aquests tractaments sol ser la necessitat d'emprar llum de la regió ultraviolada-visible, ja que les biomolècules són capaços d'absorbir-la i produïr dany cel·lular. En aquest context, la present Tesi Doctoral es centra en l'estudi de noves formes de tractament anticancerigen combinant nanomedicina i llum. Per això s'han desenvolupat nous fàrmacs fototòxics i nous materials capaços de ser activats mitjançant llum infraroja propera. En primer lloc, es van sintetitzar noves fluoroquinolones per explorar les seves propietats fototòxiques per al seu ús en fotoquimioteràpia (Capítol 3 de la Tesi). Es van estudiar les característiques fotofísiques i fotoquímiques dels nous compostos, a més de la seva capacitat per produir major fototoxicitat en les cèl·lules en comparació amb les fluoroquinolones com la lomefloxacina mitjançant l'aplicació de llum ultraviolada. En base als resultats obtinguts es va realitzar un estudi per determinar les diferències entre les interaccions d'algunes fluoroquinolones dihalogenades, incloses les comentades anteriorment, i biomolècules com ADN i proteïnes. La reactivitat de les seves intermedis fotogenerats també es va estudiar en el Capítol 4. Després de conèixer en profunditat la capacitat fototòxica dels nous fàrmacs, en el Capítol 5 es va dur a terme el disseny d'un nanosistema compost per fluoroquinolones i nanopartícules de upconversion. Es va demostrar l'alta capacitat fototòxica d'aquest nou nanosistema. D'aquesta manera, es va generar activitat fototòxica a partir d'una fluoroquinolona sense l'ús de llum ultraviolada D'altra banda, la formació de profàrmacs obre la porta a l'administració selectiva de fàrmacs contra el càncer. Els profàrmacs consisteixen en la unió fotolábil d'una molècula capaç de ser activada per la llum i el fàrmac d'interès. No obstant això, un coneixement profund de les propietats fotofísiques i fotoquímiques del fotodisparador i dels potencials redox de tots dos membres de la diada pot ser crucial per obtenir el fotoalliberament desitjada. Així, en el Capítol 6, es va destacar la rellevància d'aquestes dades utilitzant un profàrmac format per un derivat de cumarina com a molècula fotoactivable i colquicina com a fàrmac. Finalment, en el Capítol 7 es va explorar la síntesi d'un nou nanosistema que conté un profàrmac format per un derivat de cumarina unit a l'fàrmac contra el càncer clorambucilo i nanopartícules biocomatibles de upconversion. L'addició d'albúmina de sèrum humà com a recobriment de les nanopartícules compleix la doble funció d'obtenir nanopartícules biocompatibles i ser el lloc de càrrega del profàrmac. / [EN] Cancer is one of the leading causes of death worldwide. Generally used anticancer treatments have various side effects produced by their low specificity. This is one of the reasons why the search for new treatments continues. Within these new investigations is the extensive field of nanomedicine, which can be explained as the study of new materials on a nanometric scale. It can be translated in the reduction of these side effects by increasing the selectivity and specificity of the treatments. Among the nanomaterials are upconversion nanoparticles that are capable of absorbing light in the near infrared and emit it in the ultraviolet-visible region. On the other hand, since the beginning of the history of medicine, light has been used as a form of treatment, having a very important role. A drawback for such treatments is sometimes the need to use light from the ultraviolet-visible region since biomolecules are capable of absorbing and causing cell damage. In this context, this Doctoral Thesis focuses on the study of new forms of anticancer treatment combining nanomedicine and light. For this, new phototoxic drugs and new materials capable of being activated by near infrared light have been developed. First, new fluoroquinolones were synthesized to explore their phototoxic properties for using in photochemotherapy (Chapter 3 of the Thesis). The photophysical and photochemical characteristics of the new compounds were studied, in addition to their ability to produce greater phototoxicity in cells than fluoroquinolones such as lomefloxacin by applying ultraviolet light. Based on the results obtained, a study was carried out to determine the differences between the interactions of some dihalogenated fluoroquinolones including the above commented, and biomolecules such as DNA and proteins. The reactivity of their photo-generated intermediates was also studied in Chapter 4. After a deep knowledge of the phototoxic capacity of the new drugs, design of a nanosystem composed of fluoroquinolones and upconversion nanoparticles was carried out in Chapter 5. The high phototoxic capacity of this new nanosystem was demonstrated. In this way phototoxic activity was generated from a fluoroquinolone without the use of ultraviolet light. On the other hand, the formation of prodrugs opens a door to the selective administration of anticancer drugs. Prodrugs consist of the photolabile binding of a molecule capable of being activated by light and the drug of interest. However, a knowledge of the photophysical and photochemical properties of the phototrigger as well as the redox potentials of both members of the dyad can be crucial to obtain the desired photorelease. Thus, in Chapter 6, the relevance of these data was highlighted using a prodrug formed by a coumarin derivative as a photoactivatable molecule and colchicine as a drug. Finally, in Chapter 7 the synthesis of a new nanosystem containing a prodrug formed by a derivative of coumarin linked to the anticancer drug chlorambucil, and upconversion biocompatible nanoparticles was explored. The addition of human serum albumin as a coating for the nanoparticles fulfills the dual function of obtaining biocompatible nanoparticles and being the loading site for the prodrug. / Anaya González, C. (2021). Design of New Up-conversion Systems for Anticancer Therapies [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/172665 / TESIS
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In Vitro Adsorption of Heavy Metals Using Metal-Organic Frameworks

Ngule, Chrispus M., Jr 17 August 2020 (has links)
No description available.
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Synthesis, Biological Functionalization, and Integration ofCarbon Nanotubes for Bio-Sensing Textiles

Olszewski, Amy L. 03 June 2013 (has links)
No description available.
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Über die Bedeutung der Zugabe von humanem Serum-Albumin zu exogenen GLP-1-Infusionen am Beispiel der Antagonisierbarkeit des GLP-1 [7-36-Amid]-Einflusses auf die erste Phase der Insulin-Sekretion nach intravenöser Glukosegabe durch den GLP-1-Rezeptor-Antagonisten Exendin [9-39] bei gesunden Menschen / About the importance of the addition of human serum albumin to exogenous GLP-1 infusion on the example of Antagonized the GLP-1 [7-36 amide] influence on the first phase insulin secretion after intravenous administration of glucose by the GLP-1 receptor antagonist Exendin [9-39] in healthy humans

Köthe, Lars Dietrich 11 October 2011 (has links)
No description available.

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