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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.
41

Höherkoordinierte Komplexverbindungen des Siliciums, Germaniums und Zinns mit chiralen O,N,O´-Liganden

Fels, Sabine 01 November 2016 (has links) (PDF)
Aufgrund ihrer Eigenschaften und möglicher Anwendungen werden Siliciumkomplexe mit O,N,O´-Ligandsystemen in der Literatur beschrieben. Jedoch fehlen bisher Untersuchungen zur Strukturaufklärung. Im Rahmen dieser Arbeit wurden zahlreiche Silicium-, Germanium- und Zinnkomplexe mit chiralen O,N,O´-Liganden synthetisiert und strukturanalytisch charakterisiert. Dazu wurden die Liganden durch Kondensationsreaktionen von enantiomerenreinen Aminosäuren mit aromatischen ortho-Hydroxyaldehyden bzw. Acetylaceton hergestellt. Die weitere Umsetzung der Liganden mit Elementhalogeniden der Gruppe 14 führte zu den angestrebten Komplexverbindungen. Alle hergestellten Verbindungen wurden umfassend charakterisiert (NMR-, UV/Vis-, IR-Spektroskopie, Elementaranalyse, Einkristallstrukturanalyse, Drehwert). Quantenchemische Berechnungen an einfachen Modellverbindungen sowie an hergestellten Silicium- und Zinnkomplexen führten zu einem grundlegenden Verständnis der Festkörper-NMR-Parameter dieser Verbindungsklasse.
42

Polymerization and oligomerization reactions mediated by metallodendrimers of zinc and palladium

Mugo, Jane Ngima 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Please refer to full text for abstract / AFRIKAANSE OPSOMMING: Sien volteks vir opsomming
43

Tuning ultrafast chemical reaction dynamics in photoactive proteins

Bassolino, Giovanni January 2015 (has links)
This dissertation investigates the origins of tunable and efficient photochemistry in three different photoactive proteins, bacteriorhodopsin (BR), rhodopsin (RHO) and green fluorescent protein (GFP). In all cases, significant differences exist between the photoreactivity of model chromophores in solution and in the protein environment, in terms of excited state lifetime and efficiency of the primary photochemical process (opsin proteins) or the type of reaction (excited state proton transfer versus C=C double bond photoisomerisation for GFP). The work presented here investigates for each case to what extent the protein environment is necessary to alter the photochemistry of model chromophores in solution. For GFP and BR steric and electrostatic interactions between the protein pocket and the chromophore are shown to be likely responsible for shaping the excited state surface along which the photoreactions take place. For RHO it is suggested, contrary to current belief, that selection of a reactive ground state conformer might be the main effect generating the observed differences between solution and protein environment. The solution photochemistry of structurally modified retinal protonated Schiff bases, taken as model chromophores for the opsin proteins, is studied with continuous wave irradiation experiments and ultrafast transient spectroscopies. Surprisingly large differences are observed for the isomerisation reaction depending on the starting configuration (trans or cis) of the photoactive double bond. The current model for BR based on the tuning of the excited state barrier encountered along the isomerisation coordinate is expanded to include the changes in selectivity, speed and efficiency observed for a series of all-trans derivatives. For 11-cis, the photoisomerisation in solution is proposed to take place along a barrierless isomerisation coordinate, in contrast with the models currently available in literature. It is suggested that the protein might be discriminating between ground state conformers rather than significantly changing the topography of the reaction coordinate. For GFP, excited state Raman spectra are recorded for the wild-type protein, two mutants and a model chromophore in solution. It is suggested that the high frequency vibrational modes observed in the excited state spectra of the proteins but not of the model chromophore in DMSO are a sign of a tighter chromophore environment that inhibits the photoisomerisation reaction occurring in solution.
44

Design and synthesis of new metallo-organic complexes and their evaluation as anti-cancer agents : synthesis, characterisation and biological evaluation of novel, late first row transition metal Schiff base complexes, as anti-cancer metallopharmaceuticals

Lidster, Jon January 2011 (has links)
This work is concerned with the design and synthesis of the cheap, late first row transition metal complexes of Schiff base ligand systems. The prepared complexes readily afford systematic variation in order to probe potency and understand the role of metal, chelating ligands and anionic ligands when carrying out their cytotoxic effect. This study has lead to a better understanding of the action of these classes of complex and will be used to direct the design of new anti-cancer metallopharmaceuticals going forward. This thesis details the synthesis of a library of Schiff base macroacyclic ligands and their novel late first row transition metal complexes with varying anionic counterparts. The creation of a library with several degrees of variability provides a wide array of parameters to afford subtle variation in structure and chemistry e.g. denticity, co-ordination mode, chelate hole size, metal centred redox potentials, hydrolysis rates, co-ordinative saturation, lipophilicity, solubility and more. Complexation of the ligands was carried out by the free ligand and a novel macroacyclic metal template approach using the cheap late first row transition metal salts of Cobalt (II), Nickel (II), Copper (II) and Zinc (II) plus one Ru (III) complex. Structural studies of the 80 generated complexes was carried out by vibrational spectroscopy, elemental analysis, mass spectrometry, magnetic susceptibility and NMR. Single crystal X-ray structures have been determined with 20 reported in this thesis. All ligands act as tridentate ligands in all except one case to form monomeric distorted trigonal-bipyramidal, square-pyramidal or octahedral structures. In the case of zinc nitrate, the ligand L2PhMe acts as a tetradentate ligand to give a distorted octahedral structure. Paramagnetic NMR and solution magnetic susceptibility of paramagnetic complexes was achieved by the Evans NMR method and analysis of the solution NMR showed that L2R and L3R ligands display 2-fold symmetry and are likely either tetradentate in solution or a fast exchange between imine N-donar sites is occurring even down to -65°C. The majority of the resulting complexes of L1R were screened against a panel of three cancer cell lines. Several categories of complex were able to afford structure activity relationships. It was discovered that the ligand is indeed essential for activity of the metal salts against the panel of cell lines and it was largely discovered that the variation in 'tail group' and anionic coordinating ligands played little role in providing a dramatic variation in activity of the metal salt. In general all L1R complexes displayed moderate cytotoxicity showing a trend in activity with respect to the metal in the order RuIII≈CoII>CuII≈ZnII>NiII, over a 6 day exposure to the three cell panel RuIII was shown to be the most potent metal of the L1R series providing IC50 values of 4.6 (0.7) and 7.5 (1.2) μM against the DLD-1 and H460 cell lines respectively, which is Ca. 4.6 and 15 times less potent than cisplatin to the same cell panel respectively. RuIII was also discovered to be the only metal to provide an IC50 value from a 1 hour exposure to the DLD-1 cell panel. The value of 20.4 (3.5) μM is a moderate figure but again Ca. 10 fold less potent than cisplatin for the same test. The L2R and L3R complexes could not be screened by the same comprehension due to their low solubilities. However the lone screen that was possible from the very sparingly soluble complex [CuCl2(L3Bui)] gave the most exciting result and most potent complex of this thesis. After a 6 day exposure, [CuCl2(L3Bui)] gave IC50 values of 4.3 (0.1) and 2.9 (0.1) μM against the DLD-1 and H460 cell lines respectively. These values are merely 4 and 6 fold more than Cisplatin to the same cell lines respectively and demonstrates the potential of this class of complex as cytostatic agents. Further studies utilising a semi-quantitative DNA damaging assay, demonstrated that all first row complexes can damage DNA when in the presence of hydrogen peroxide, with the exception of ZnII complexes. CoII appeared to afford the greatest DNA damage with the most intsense bands for double strand breaks and the CuII complex of the ligand L3Bui also demonstrated a greater DNA damage as opposed to its L1Bui analogue.
45

Síntese, caracterização e estudo da atividade biológica de bases de Schiff biopoliméricas, preparadas a partir de quitosanas e salicilaldeídos e seus complexos de Zn(II), Pd(II) e Pt(II) / Synthesis, characterization and study of the biological activity of biopolymeric Schiff bases prepared of chitosan and salicylaldehydes and their complexes of Zn(II), Pd(II) and Pt(II)

Barbosa, Hellen Franciane Gonçalves 27 April 2018 (has links)
Este trabalho teve como objetivo a síntese e a caracterização de bases de Schiff biopoliméricas e alguns de seus complexos metálicos formados a partir do biopolímero quitosana. Na primeira etapa do trabalho foram utilizados o salicilaldeído e seus derivados, 5-metóxisalicilaldeído e 5-nitrosalicilaldeído para produzir as bases de Schiff biopoliméricas com a quitosana (GD = 90,4 %, Mw =223 kDa), as quais foram utilizadas para a síntese dos complexos de Zn(II), Pd(II) e Pt(II). Na segunda etapa, bases de Schiff biopoliméricas anfifílicas foram sintetizadas utilizando as quitosanas (GD = 90,4 e 89%, Mw = 223 e 64 kDa), e o grupo hidrofóbico salicilaldeído bem como o grupo hidrofílico 2,3-epóxi-1-propanol (glicidol). E esses ligantes também foram utilizados para complexar os metais Zn(II), Pd(II) e Pt(II). As bases de Schiff biopoliméricas anfifílicas foram sintetizadas a fim de se avaliar o efeito da presença do grupo hidrofílico glicidol e também o da variação dos valores de Mw nas propriedades físico-químicas e biológicas. Todos os compostos sintetizados foram caracterizados por espectroscopia (1H-RMN, FTIR, DRX, UV-Vis), análise térmica (TG/DTG-DTA) e microscopia (MEV-EDX). Afim de se avaliar a atividade biológica das bases de Schiff biopoliméricas e seus complexos foram utilizados dois agentes patógenos de plantas: a bactéria Gram-negativa Pseudomonas syringae pv. tomato e o fungo de cerais Fusarium graminearum. Os resultados obtidos demostraram que tanto as bases de Schiff biopoliméricas quanto seus complexos exibiram atividade antibacteriana significante.  Entretanto, o potencial antifúngico das bases de Schiff foi melhor que para alguns complexos, devido a diferença morfológica relacionada a constituição da membrana celular externa e da parede celular dos microrganismos testados. Portanto, foi observado que a morfologia é um fator diretamente relacionado aos mecanismos de ação. A avaliação da citotoxicidade foi realizada in vitro contra células de carcinoma de mama MCF-7 por ensaio de MTT. Os resultados de citotoxicidade obtidos demonstraram que todos os compostos apresentaram uma diminuição na percentagem da viabilidade celular, em função da concentração. Observou-se para as bases de Schiff biopoliméricas uma atividade antitumoral mais efetiva que para as quitosanas sem modificação. Em baixas concentrações dos complexos, observou-se uma baixa inibição celular, especialmente para os complexos de zinco. Porém, em concentrações mais elevadas, foi verificado um aumento significativo da toxicidade. Portanto, a principal contribuição esperada deste trabalho foi a síntese, caracterização e estudo desses novos compostos de bases de Schiff biopoliméricas e dos biocomplexos, com potencial para atuar em aplicações biológicas. / Biopolymeric Schiff bases prepared from chitosan and some of their complexes were synthesized, characterized and evaluated regarding their biological activity. In a first step, salicylaldehyde, 5-methoxysalicylaldehyde and 5-nitrosalicylaldehyde were used to synthesize biopolymeric Schiff bases with chitosan (GD = 90.4 %, Mw =223 kDa), as well as their Zn(II), Pd(II) and Pt(II) complexes. In a second stage, amphiphilic biopolymeric Schiff bases were prepared from two different chitosans (GD = 90.4 and 89%, Mw = 223 e 64 kDa), but introducing the salicylaldehyde hydrophobic group and also 2,3-epoxy-1-propanol (glycidol) hydrophilic group. Zn(II), Pd(II) and Pt(II) complexes where prepared from such amphiphilic biopolimeric ligands. All these ligands and respective complexes were obtained in order to evaluate the effect of increased solubility caused by glycidol the hydrophilic group and as well as the different Mw values in physical chemical and biological properties. Thus different spectroscopic (1H-NMR, FTIR, XRD, UV-Vis), thermal analytical (TG/DTG-DTA) and microscopy (MEV-EDX) techniques were used to characterize all the compounds. The biological activity was evaluated against two economically important plant pathogens, Gram-negative bacteria Pseudomonas syringae pv. tomato and Fusarium graminearum cereal fungus. In general, the results demonstrated that biopolymer Schiff bases and their complexes exhibited significant antibacterial activity. However, the antifungal potential of the Schiff bases was better than for some complexes, due to the morphological difference related to the constitution of the cell membrane and cell wall of the tested microorganisms. Therefore, it was observed that morphology is a factor directly related to the mechanisms of action. Cytotoxicity was evaluated in vitro against breast cancer cells (MCF-7) using MTT. The results of cytotoxicity against MCF-7 cells demonstrated a decrease in the cell viability as a function of the concentration, for all the samples tested, being the biopolymeric Schiff bases were more effective antitumor agent than chitosan itself. In lower concentration, the complexes did not show effective decrease on cells viability, especially for zinc complexes. However, at high concentrations a significant increase of cytotoxicity was observed. Therefore, the main contribution expected these work was the synthesis, characterization and biological activity evaluation of these new biopolymeric Schiff bases and complexes, aiming to evaluate the antimicrobial and antitumor activity.
46

Ion/Ion Reaction Facilitated Mass Spectrometry and Front-End Method Development

Nan Wang (6565601) 10 June 2019 (has links)
Mass spectrometry is a versatile analytical tool for chemical and biomolecule identification, quantitation, and structural analysis. Tandem mass spectrometry further expands the applications of mass spectrometry, making it more than a mere detector. With tandem mass spectrometry, the mass spectrometer is capable of probing reaction mechanisms, monitoring reaction processes, and performing fast analysis on complex samples. In tandem mass spectrometry, after activation the precursor ions fragment into small fragment ions through one or more pathways, which are affected by the ion’s inherit property, the ion type, and the activation method. To obtain complementary information, one can alter the fragmentation pathway by changing the ion via ion charge manipulation and covalent modification to the ion. Gas-phase ion/ion reactions provide an easy approach to changing ion type and facile modification to the analyte ions. It has been extensively used for spectrum simplification and analyte structural studies. In this dissertation, ion/ion reaction facilitated mass spectrometry methods are studied, and explorations into the method development involving front-end mass spectrometer are discussed.<br>The first work demonstrates a special rearrangement reaction for gas-phase Schiff-base-modified peptides. Gas-phase Schiff-base modification of peptides has been applied to facilitate the primary structural characterization via tandem mass spectrometry. A major or minor fragment pathway related to the novel rearrangement reaction was observed upon in-trap collisional activation of the gas-phase Schiff-base-modified peptides. The rearrangement reaction involves the imine of the Schiff base and a nucleophile present in the polypeptide. The occurrence of the rearrangement reaction is affected by several factors, such as ion polarity, identity of the nucleophile in the peptide (e.g., side chains of lysine, histidine, and arginine), and the position of the nucleophile relative to the imine. The rearrangement reaction does not affect the amount of structural information that can be obtained by collisional activation of the Schiff-base-modified peptide, but when the rearrangement reaction is dominant, it can siphon away signal from the structurally diagnostic processes.<br>Efforts have also been put into the method development of peptide and protein aggregation detection via electrospray ionization mass spectrometry (ESI-MS). People have studied peptide and protein aggregation processes to understand the mechanism of amyloid-related diseases and to control the quality of the peptide and protein pharmaceuticals. ESI-MS is suitable for solution aggregation studies because of its compatibility with solution samples and the straightforward result of the analyte’s oligomeric state on the mass spectrum. However, peak overlap issue and nonspecific aggregation in the ESI process can obscure the result. Here, the application of proton transfer ion/ion reaction to the analyte has been found useful to reduce or eliminate the peak overlap issue. A statistical model based on Poisson statistics has been proposed to deal with the ESI-induced nonspecific aggregation in the droplet and to differentiate the solution-phase aggregation from the droplet-induced aggregation. Factors that affect the accuracy of the statistical model have been discussed with MATLAB simulations.<br>In the era of biological system studies, sample complexity is a challenge every analytical chemist has to face. The analysis of complex sample can be facilitated by the combination of separation techniques outside the mass spectrometer (such as differential mobility spectrometry (DMS)) and ion structure probing techniques inside the mass spectrometer (such as tandem mass spectrometry and gas-phase ion/ion reactions). Here the coupling method between DMS and ion/ion reaction is developed and tested with model peptide systems to demonstrate its possible application in complex sample characterization such as isomer identification.<br>
47

Koordinationsverbindungen von Schiff-Basen des 3-Aminopropyltriethoxysilans und 3-(2-Aminoethylamino)-propyl-trimethoxysilans mit α-Hydroxybenzocarbonyl-Verbindungen

Efendi, Jon 31 July 2009 (has links) (PDF)
Die vorliegende Arbeit befasst sich mit Untersuchungen zur Komplexbildung von Cu2+, Zn2+, sowie Sn2+ und B(OMe)3 mit den Schiff-Basen aus 3-Aminopropyl-triethoxysilan (APTES) und 3-(2-Aminoethyl-amino)-propyl-trimethoxysilan (AEPTMS) mit α-Hydroxybenzocarbonylverbindungen. Die Liganden und die Komplexe wurden mit IR-, UV/VIS- und NMR-Spektroskopie charakterisiert. IR-Untersuchungen zeigen die charakteristischen C=N- und C=O-Valenzschwingungen. Sie werden durch die Komplexbildung deutlich verschoben. Die 1H- und 13C-NMR-Messungen indizieren die Komplexbildung mit einer signifikanten Verschiebung in den Signallagen der H- und C-Nachbaratome der Donatoratome. 29Si-NMR-Messungen indizieren keine Hydrolyse- und Kondensationsreaktionen im Verlauf der Synthese. Bei der Komplex-Synthese mit wasserhaltigen Übergangsmetallsalzen wurden Produkte von Sol-Gel-Prozessen gefunden. UV/VIS-spektroskopische Untersuchungen an den Mischungen der Übergangsmetallsalze mit APTES bzw. AEPTMS zeigen die Bildung typischer Aminkomplexe.
48

3-amino-2-tiokso-tizolidin-4-ono darinių sintezė ir jų antimikrobinio poveikio įvertinimas / Synthesis of 3-amino-2-thioxo-thiazolidin-4-one derivatives and evaluation of antimicrobial activity

Smetanin, Vadim 18 June 2014 (has links)
Darbo tikslas: susintetinti 3-amino rodanino pagrindą turinčius junginius ir nustatyti jų antimikrobinį aktyvumą. Uždaviniai: 1) Sintezuoti 3-amiono-2-tiokso-4-tiazolidinono darinius; 2) Įvertinti gautų junginių antimikrobinį aktyvumą, naudojant in silico PASS online. 3) Įvertinti gautų junginių antimikrobinį aktyvumą in vitro standžioje terpėje; 4) Susieti junginių struktūrą su antimikrobiniu aktyvumu. Tyrimo metodai: sintetintų junginių antimikrobinis poveikis buvo prognozuojamas „PASS online“ programos pagalba. Antimikrobinis aktyvumas tirtas in vitro, naudojant Miulerio – Hintono agarą. Atlikti ESC tyrimai junginių grynumui nustatyti ir FT-IR tyrimai junginių struktūrai patvirtinti. Tyrimo rezultatai: 3-aminorodanino pagrindu buvo sintetinti 7 junginiai, turintys Šifo bazės struktūrą ir 1 turintis azetidino funkcinę grupę. Atlikti junginių lydymosi temperatūros nustatymo tyrimai, grynumas nustatytas naudojant ESC, junginių struktūra patvirtinta naudojant FTIR metodiką. PASS online programos pagalba buvo nustatyta, kad dauguma junginių turį potencialų antimikrobinį poveikį. Antimikrobinio poveikio in vitro tyrimo metu buvo nustatyta, kad plačiausią poveikį turi junginys VS-3, turintis p-chlorbenzaldehido pakaitą, ir VS-2, turintis p-brombenzaldehido pakaitą. Taip pat nustatyta, kad ribotu antimikrobiniu aktyvumu pasižymėjo junginiai VS-6, VS-7, VS-8. Įterpus azetidino struktūrą į VS-1 junginį, aktyvumas padidėjo Candida grybelių atžvilgiu. Išvados: iš sintetintų junginių... [toliau žr. visą tekstą] / The aim of the research: Synthesis of 3-aminorhodanine derivatives, antimicrobial evaluation. Methods: Antimicrobial activity of synthesized 3-aminorhodanine derivatives was predicted with the help of PASS online program. Factual antimicrobial activity of compounds was determined using in vitro agar method. The purity and structure of compounds was analyzed with ESC and FT-IR methods accordingly. Results: 7 Schiff base derivatives and one azetidine compound were synthesized on the base of 3-aminorhodonine. The melting points were identified, the purity of compounds were determined using ESC, the compound structure was identified using FTIR. Analyzing the compounds with PASS online showed that most of the compounds possess the potential of antimicrobial activity. In vitro antimicrobial studies showed that the widest spectrum of activity was possessed by compound VS-3, which had the 4-chlorbenzaldehyde moiety, and VS-2 with 4-bromobenzaldehyde moiety. Compounds VS-6, VS-7 and VS-8 showed limited antimicrobial activity. Modifying VS-1 structure by adding an azotidine moiety increased the drugs effect on Candida fungi family. Conclusion: amongst all the synthesized compounds 3-(4-chlorophenyl)methyleneamino]-2-thioxo-thiazolidin-4-one and 3-(4-bromphenyl)methyleneamino]-2-thioxo-thiazolidin-4-one showed most antimicrobial promise.
49

Efeitos dos complexos de níquel e platina derivados de base de Schiff no câncer de bexiga urinária não-músculo invasivo / Effects of nickel and platinum complexes derived from Schiff base on non–muscle invasive urinary bladder cancer

Matsumoto, Mirian Yoshiko 30 May 2017 (has links)
Submitted by Mirian Yoshiko Matsumoto (mirian_matsumoto@hotmail.com) on 2018-09-13T03:42:01Z No. of bitstreams: 1 Tese de Doutorado BGA Mirian Matsumoto.pdf: 5590776 bytes, checksum: 35a18a86dcfd4a42e7e9c40dbce00a94 (MD5) / Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2018-09-14T16:51:20Z (GMT) No. of bitstreams: 1 matsumoto_my_dr_bot.pdf: 5590776 bytes, checksum: 35a18a86dcfd4a42e7e9c40dbce00a94 (MD5) / Made available in DSpace on 2018-09-14T16:51:20Z (GMT). No. of bitstreams: 1 matsumoto_my_dr_bot.pdf: 5590776 bytes, checksum: 35a18a86dcfd4a42e7e9c40dbce00a94 (MD5) Previous issue date: 2017-05-30 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O câncer de bexiga (CB) é a segunda malignidade geniturinária mais comum. A maioria (75%) dos CBs são primeiramente diagnosticados como não-músculo invasivos (CBNMIs) nos estádios Ta, T1, e carcinoma in situ (CIS). Atualmente, o tratamento mais utilizado contra CBNMIs envolve a imunoterapia com Bacillus Calmette-Guérin (BCG) associada à ressecção transuretral (RTU). No entanto, a utilização de BCG pode causar graves efeitos colaterais e está associada com uma elevada taxa de recorrência após o tratamento. Por conseguinte, várias abordagens têm sido investigadas, incluindo o desenvolvimento de novas moléculas, assim como a melhoria da terapia com medicamentos convencionalmente utilizados no tratamento de tumores e a incorporação de sistemas de carreamento de fármacos. Considerando o uso de novas moléculas, complexos metálicos derivados de bases de Schiff (BSs) são compostos versáteis que apresentam atividade antitumoral, fornecendo assim novas perspectivas para a terapia do CBNMI. Em relação ao carreamento de fármacos, ao longo dos últimos anos, carreadores lipídicos nanoestruturados (CLNs) têm atraído considerável interesse como veículos alternativos para produtos farmacêuticos antitumorais. Assim, com o intuito de adquirir maior conhecimento a respeito da química dos complexos derivados da BS N-Salicilideno anilina (Salan) e também seus efeitos na progressão do CBNMI, esta tese descreve a síntese e caracterização de complexos N-Salicilideno anilina(níquel) [Salan(Ni)] e N-Salicilideno anilina(platina) [Salan(Pt)]. A estrutura proposta desses compostos foi estabelecida por análise elementar (CHN), FTIR, TG, RMN de 1H e 13C. As atividades citotóxicas dos compostos sintetizados [Salan, NiCl2 e Salan(Ni)] foram avaliadas por ensaio MTT e os dados obtidos indicaram que Salan(Ni) demonstrou atividade citotóxica significativa contra linhagens celulares de leucemia e câncer de fígado. Além disso, neste estudo os efeitos histopatológicos e moleculares dos compostos sintetizados [Salan, Salan(Ni) e Salan(Pt)] foram caracterizados e comparados com o tratamento com BCG em um modelo animal de CBNMI. Os resultados obtidos indicaram que o grupo Salan(Ni): apresentou melhor recuperação histopatológica quando comparado ao grupo Câncer; aumentou os níveis da proteína UPIII; aumentou a expressão dos genes supressores de tumor PTEN e p53; causou inibição da angiogênese devido aos níveis proteicos elevados de endostatina e níveis mais baixos da proteína VEGF. No entanto, durante a instilação dos tratamentos, observou-se a precipitação dos compostos. Então, testes utilizando 2% de DMSO em óleo de milho como veículo para complexos do tipo Salan [Salan(Ni) e Salan(Pt)] foram realizados. Adicionalmente, o complexo Salan(Pt) foi incorporado a um carreador lipídico nanoestruturado (CLN) derivado de murumuru. O CLN carregado com Salan(Pt) [Salan(Pt)-CLN] foi preparado através do sistema de agitação mecânica e apresentou diâmetro médio de 165,4 nm e potencial zeta -34,4 mV. Por fim, os compostos obtidos [Salan(Ni), Salan(Pt), CLN livre, Salan(Pt)-CLN] foram administrados in vivo para avaliar seus efeitos contra CBNMI. A análise histológica revelou que o grupo Salan(Ni) apresentou melhor recuperação histopatológica. Análises de Western blotting (WB) indicaram que os tratamentos com Salan(Ni), Salan(Pt) e Salan(Pt)-CLN provavelmente ativam a via p53 diminuindo os níveis proteicos de Akt e PI3K. Em conclusão, os resultados indicaram que o complexo Salan(Ni) apresentou melhores efeitos na redução da agressividade do CBNMI comparado aos demais complexos e BCG. / Bladder cancer (BC) is the second most common genitourinary malignancy. Most (75%) BCs are non–muscle invasive (NMIBC) at first diagnosis [Ta, T1, and carcinoma in situ (CIS)]. Currently, the most used treatment against NMIBC involves the immunotherapy with BCG (Bacillus Calmette-Guérin) associated with the transurethral resection. However, the use of BCG can cause severe side effects and it is associated with high recurrence rate after treatment. Therefore, several approaches have been investigated, including the development of new molecules and also the improvement of the therapy with drugs conventionally used to treat cancers by using drug delivery systems. Considering the use of new molecules, metal complexes derived from Schiff bases (SBs) are versatile molecules with anticancer activity, providing new perspectives for the therapy of NMIBC. Regarding the drug delivery, over the past few years, nanostructured lipid carriers (NLCs) have been attracting considerable interest as alternative carriers for anticancer pharmaceuticals. Thus, in order to acquire more information about the chemistry of the complexes derived from the SB of N-Salicylidene aniline (Salan), as well as its effects on the progression of NIMBC, the present thesis describes the synthesis and characterization of N-Salicylidene aniline(nickel) [Salan(Ni)] and N-Salicylidene aniline(platinum) [Salan(Pt)] complexes. The proposed structure of these compounds was established by elemental analysis (CHN), FTIR, TG, 1H and 13C NMR. Cytotoxic activities of the synthesized compounds [Salan, NiCl2 and Salan(Ni)] were evaluated by the MTT assay and the obtained data indicated that Salan(Ni) showed significant cytotoxic activity against leukemia and liver cancer cells lines. Furthermore, in this study the histopathological and molecular effects of the synthesized compounds [Salan, Salan(Ni) and Salan(Pt)] were characterized and compared with BCG treatment in an animal model of NMIBC. Our results demonstrated that the Salan(Ni) group: improved histopathological recovery when compared with Cancer group; increased UPIII protein levels; increased expression of tumor suppressors genes PTEN and p53; inhibited of angiogenesis assigned to elevated levels of endostatin and lower levels of VEGF. However, during the instillation of treatments, compounds precipitation were observed. Then, tests using 2% DMSO in corn oil as vehicle for Salan-type complexes [Salan(Ni) and Salan(Pt)] were performed. Additionally, Salan(Pt) complex was incorporated into nanostructured lipid carrier (NLC) derived from murumuru. The NLC loaded with Salan(Pt) [Salan(Pt)-NLC] was prepared by using mechanical agitation method and had an average diameter of 165,4 nm as well as zeta potential of -34,4 mV. Ultimately, the obtained compounds [Salan(Ni), Salan(Pt), free NLC, Salan(Pt)-NLC] were administered in vivo to evaluete their effects against NMIBC. The histological analysis revealed that Salan(Ni) group Abstract MATSUMOTO, M. Y. Tese de Doutorado em Biologia Geral e Aplicada – UNESP – Botucatu showed bestter histopathological recovery. Western blotting (WB) analysis indicated that Salan(Ni), Salan(Pt) and Salan(Pt)-NLC treatments probably activate the p53 pathway by decreasing the protein levels of Akt and PI3K. In conclusion, the results showed the Salan(Ni) has better effects in reduction of NMIBC aggressiveness compared to the other complexes and BCG / 2013/04708-8
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Efeitos dos complexos de níquel e platina derivados de base de Schiff no câncer de bexiga urinária não-músculo invasivo

Matsumoto, Mirian Yoshiko January 2017 (has links)
Orientador: Wagner José Fávaro / Resumo: O câncer de bexiga (CB) é a segunda malignidade geniturinária mais comum. A maioria (75%) dos CBs são primeiramente diagnosticados como não-músculo invasivos (CBNMIs) nos estádios Ta, T1, e carcinoma in situ (CIS). Atualmente, o tratamento mais utilizado contra CBNMIs envolve a imunoterapia com Bacillus Calmette-Guérin (BCG) associada à ressecção transuretral (RTU). No entanto, a utilização de BCG pode causar graves efeitos colaterais e está associada com uma elevada taxa de recorrência após o tratamento. Por conseguinte, várias abordagens têm sido investigadas, incluindo o desenvolvimento de novas moléculas, assim como a melhoria da terapia com medicamentos convencionalmente utilizados no tratamento de tumores e a incorporação de sistemas de carreamento de fármacos. Considerando o uso de novas moléculas, complexos metálicos derivados de bases de Schiff (BSs) são compostos versáteis que apresentam atividade antitumoral, fornecendo assim novas perspectivas para a terapia do CBNMI. Em relação ao carreamento de fármacos, ao longo dos últimos anos, carreadores lipídicos nanoestruturados (CLNs) têm atraído considerável interesse como veículos alternativos para produtos farmacêuticos antitumorais. Assim, com o intuito de adquirir maior conhecimento a respeito da química dos complexos derivados da BS N-Salicilideno anilina (Salan) e também seus efeitos na progressão do CBNMI, esta tese descreve a síntese e caracterização de complexos N-Salicilideno anilina(níquel) [Salan(Ni)] e N-Sa... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Bladder cancer (BC) is the second most common genitourinary malignancy. Most (75%) BCs are non–muscle invasive (NMIBC) at first diagnosis [Ta, T1, and carcinoma in situ (CIS)]. Currently, the most used treatment against NMIBC involves the immunotherapy with BCG (Bacillus Calmette-Guérin) associated with the transurethral resection. However, the use of BCG can cause severe side effects and it is associated with high recurrence rate after treatment. Therefore, several approaches have been investigated, including the development of new molecules and also the improvement of the therapy with drugs conventionally used to treat cancers by using drug delivery systems. Considering the use of new molecules, metal complexes derived from Schiff bases (SBs) are versatile molecules with anticancer activity, providing new perspectives for the therapy of NMIBC. Regarding the drug delivery, over the past few years, nanostructured lipid carriers (NLCs) have been attracting considerable interest as alternative carriers for anticancer pharmaceuticals. Thus, in order to acquire more information about the chemistry of the complexes derived from the SB of N-Salicylidene aniline (Salan), as well as its effects on the progression of NIMBC, the present thesis describes the synthesis and characterization of N-Salicylidene aniline(nickel) [Salan(Ni)] and N-Salicylidene aniline(platinum) [Salan(Pt)] complexes. The proposed structure of these compounds was established by elemental analysis (CHN), FTIR, TG... (Complete abstract click electronic access below) / Doutor

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