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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.
221

Explaining and predicting the single channel versus multi-channel consumer : the case of an embarrassing product

Londono, Juan Carlos January 2013 (has links)
The fundamental purpose of this thesis was to determine how effective is the theory of planned behaviour (TPB) to predict and explain shopping for embarrassing products in single and multi-channel. This is important because multi-channel consumers buy more, the question is why (Neslin, Grewal et al. 2006). The question was answered by comparing consumer behaviour in three different channels: drugstore, internet and multi-channel. The Theory of Planned Behaviour (TPB) has been successful to predict intentions for a wide variety of products and behaviours. However, little is known about how effective it is when the behaviour under study is influenced by the emotion of embarrassment. Similarly, the TPB is parsimonious and has a good predictive power; nevertheless, this thesis identified that the TPB could be more effective if it considered: (1) the role of positive and negative emotions (2) other determinants of choice like personality and demographics (3) variables that are useful to make marketing decisions like the synergistic effect of brands, retailers and channels (4) variables that explain consumer response like approach and avoidance. To provide a comprehensive theoretical framework that is able to understand single and multi-channel, this thesis integrated the TPB within the Stimulus-Organism-Response (S-O-R) framework. To evaluate the proposed model, the study used a context and target product that resonated with the theory: the purchase of Regaine (a hair loss product that is embarrassing to buy) in Boots (a well-known UK. multi-channel drugstore). The embarrassing nature of Regaine created differences in the importance that variables play in each channel. The results were analysed using partial least squares structural equation modelling (PLS-SEM) and the three shopping environments were compared using multi-group analysis (MGA). The effectiveness of the TPB was improved. The variance explained (R² to intention) was 73 percent for the drugstore, 67 percent for the internet and 54 percent for multi-channel. However, subjective norm (SN) was the only factor that achieved significance for the three shopping environments. Personality and demographic factors had a low but significant moderating effect on intention. This thesis built on a series of contributions in different areas, such as the TPB, attitudes, subjective norm, perceived behavioural control, embarrassing products, multi-channel, marketing, emotions, personality and demographics. Future research should expand this thesis to other embarrassing products, industries and social media settings.
222

Farmakološki efekti sirupa i tinkture timijana / Pharmacological effects of thyme syrup and tincture

Kvrgić Maja 21 September 2016 (has links)
<p>Poslednjih godina je prisutan trend povratka prirodi i upotrebi biljnih lekova, kako u prevenciji tako i u lecenju razlicitih bolesti. Timijan (Thymus vulgaris L.) se u narodnoj medicini koristio u lecenju respiratornih oboljenja kao &scaron;to su ka&scaron;alj, bronhitis i astma. Rezultati novijih istraživanja pokazuju da timijan poseduje i druga potencijalno korisna farmakolo&scaron;ka svojstva (antimikrobna, antiinflamatorna, antioksidativna, spazmoliticka, antidijabetesna i anksioliticka). Ciljevi ovog istraživanja su bili da se ispitaju farmakodinamske osobine preparata timijana, njihove interakcije sa lekovima koji deluju na centralni nervni sistem, uticaj na funkciju jetre i parametrem oksidativnog stresa kod životinja izloženih ugljentetrahloridu, kao sadržaj karvakrola i timola u sirupu timijna, pri razlicitim uslovima cuvanja. U farmakodinamskim ispitivanjima kao eksperimentalne životinje kori&scaron;ceni su mi&scaron;evi soja NMRI, a u svim drugim ispitivanjima pacovi soja Wistar. Tinktura timijana je primenjena u dozi od 0,4mk/kg, a sirup u dozi od 12,08 ml/kg, na mi&scaron;evima. Primenjene doze na pacovima su bile 0,18 ml/kg za tinkturu i 5,6 ml/kg za sirup timijana. Za ispitivanje analgetickog dejstva kori&scaron;ceni su metod vrele ploce i test sircetne kiseline. Za procenu motorne koordinacije kori&scaron;cen je test rotirajuceg &scaron;tapa, a za procenu hipnotickog delovanja mereno je vreme spavanja. Prilikom ispitivanja uticaja preparata timijana na farmakokinetiku paracetamola, odre_ivana je koncentracija ovog leka HPLC metodom, a nakon toga su odreeni farmakokinetski parametri paracetamola. Antioksidantna aktivnost preparata timijana odre_ivana je pomocu in vitro i in vivo testova. Nakon žrtvovanja životinja ra_ena je histopatolo&scaron;ka analiza jetrenog tkiva, a u serumu su odre_ivani biohemijski parametri, kao i pokazatelji bubrežene i jetrene funkcije. Sadržaj timola i karvakrola i sirupu timijana odre_en je GC/MS metodom. Sirup i tinktura timijana su pokazali analgeticki efekat u testu vrele ploce, kao i smanjenje broja grceva izazvano primenom sircetne kiseline. Sedmodnevna primena preparata timijana smanjila je analgeticko dejstvo kodeina, a pojacala analgeticki efekat paracetamola. Sirup timijana je potencirao diazepamom izazvan poremecaj motorne koordinacije. Ispitivanjem uticaja preparata timijana na hipnoticko delovanje pentobarbitala, postignuti su razliciti rezultati u zavisnosti od dužine trajanja pretremana. Sedmodnevna primena timijana je produžila vreme trajanja spavanja, dok je jednokratna primena timijana skratila vreme trajanja spavanja. Nakon i intravenske i peroralne primene paracetamola, grupe životinja koje su bile pretretirane preparatima timijana imale su krace poluvreme eliminacije i vecu konstantu eliminacije. Upotreba samo preparata timijana nije imala uticaj na biohemijske i histolo&scaron;ke promene jetrene funkcije. S druge strane, upotreba tincture timijana u kombinaciji sa ugljen-tetrahloridom dovela je do porasta vrednosti AST i ALT enzima u serumu, dok je sirup timijana u kombinaciji sa ugljentetrahloridom smanjio aktivnost aminotransferaza. Najvece odstupanje u koncentracijama aktivnih komponenti timola i karavkrola, pokazali su sirupi cuvani na sobnoj temperaturi (20&deg;C), u sekundarnoj ambalaži i na svetlom mestu. Rezultati dobijeni u toku ovog istraživanja ukazuju da preparati timijana uticu na farmakodinamske osobine kodeina, paracetamola, diazepama i pentobarbitala, kao i na farmakokinetiku paracetamola. Upotreba preparata timijana ispoljila je analgeticki efekat i umanjila posledice izloženosti oksidativnom stresu. Uslovi cuvanja sirupa timijana uticali su na njegovu stabilnost.</p> / <p>In recent years is present trend of return to nature and the use of herbal medicines in prevention and treatment of different diseases. Thyme (Thymus vulgaris L.) was used in folk medicine in the treatment of respiratory diseases such as cough, bronchitis and asthma. The new research results have demonstrated that thyme has many others potentially useful pharmacological properties (antimicrobial, antiinflammatory, antioxidant, antispasmodic, antidiabetic and anxiolytic). The aims of this research were to determine the pharmacodynamic properties of thyme preparations and their interactions with central nervous system drugs, influence on liver function and oxidative stress parameters of animals exposed to carbon tetrachloride, as well as concentration of thymol and carvacrol in thyme syrup, at different storage conditions. In pharmacodynamics examination as experimental animals were used NMRI mice, while in all other test were used Wistar rats. Applied dose of thyme tincture was 0.4 ml/kg and of syrup 12.08 ml/kg, for mice. For rats, applied doses of tincture and syrup were 0.18 ml/kg and 5.6 ml/kg, respectively. The analgesic activity was examined by the hot plate test and acetic acid test. The Rotarod test was used to evaluate the motor coordination and to evaluate hypnotic activity sleeping time was mesaured. In order to examine the influence of thyme preparations on pharmacokinetics of paracetamol, the concentracion of this drug was measured by HPLC metods, and after that pharmocokinetic parameters of paracetamol were determined.The antioxidant acivity of thyme preparations was determined by using in vitro and in vivo tests. After animals sacrificing, histopathological analysis of liver tissue were peroformed, in serum were determined biochemical parameters and renal and hepatic function parameters. Quantification of thymol and carvacrol in syrup was carried out by GC/MS method. Thyme syrup and thyme tincture exhibited analgesic activity in hot plate test and reduced the number of writhes induced by acetic acid. Seven-day pretreatment with thyme preparations reduced analgesic activity of codeine and increased analgesic effect of paracetamol. Thyme syrup potentiated diazepam induced motor coordination impairment. Examining the impact of thyme preparations on hypnotic effect induced by pentobarbital, different results were achieved depending on the duration of pretreatment. Seven-day pretreatment with thyme had prolonged the sleeping time, while after single dose of thyme the sleeping time was decreased. After intravenous and after oral administration of paracetamol, groups pretreated with thyme preparations had decreased elimination half-life and increased elimination constant rate. Administration of thyme preparations alone did not change biochemical nor histological markers of hepatic function. On the other hand, co-administration of thyme tincture and carbon tetrachloride resulted in exacerbation of AST and ALT values in serum, while thyme syrup in coadministration with carbon tetrachloride managed to reduce activities of aminotransferases. The concentration of major active compounds, thymol and carvacrol, was mostly changed when syrups were stored at room temperature (20&deg;C), in secondary containers and in light place. Results obtained in this study demonstrated that thyme preparations do affect pharmacodynamic properties of codeine, paracetamol, diazepam and pentobarbital and pharmacokinetics of paracetamol. Administration of thyme preparations exhibited analgesic activity and reduced the effects of exposure to oxidative stress. Storage conditions of thyme syrup did affect its stability.</p>
223

Internetový výukový atlas zaměřený na půdní členovce / Internet Educational Atlas Focusing on Soil Arthropods

Dvořáková, Jana January 2013 (has links)
The main objective of this thesis was to create an educational website aimed at soil arthropods. It can be used primarily by teachers of biology and ecology, lecturers of extracurricular science education or by the students who are interested in this issue. This photographic atlas of soil arthropods consists of my own micro images obtained by the use of light and scanning electron microscope. The micro images are accompanied by text to each group of soil arthropods, which is divided into sections containing information about the systematic classification, anatomy and morphology, biology and importance, eventually representatives of the group. The atlas is accompanied by other materials usable in the classroom, such as didactic test, didactic game and proposals for group work, worksheet, field and laboratory work or educational presentations focused on soil arthropods. These materials can be downloaded from the website, along with the entire atlas of soil arthropods. The atlas is available on the following address: https://sites.google.com/site/pudniclenovci/. The review of the literature deals with the importance of arthropods in the soil and their mutual interactions. Then I describe the methods of study of arthropods (sampling, sample preparation for light and scanning electron microscopy and...
224

Design, Synthesis and Biological Evaluation of Novel Compounds with CNS-Activity Targeting Cannabinoid and Biogenic Amine Receptors

Sherwood, Alexander M 16 May 2014 (has links)
This work seeks to contribute to the discipline of neuropharmacology by way of structure activity relationship from the standpoint of an organic chemist. More specifically, we sought to develop robust synthetic methodology able to efficiently produce an array of compounds for the purpose of systematic evaluation of their interaction with specific sights within the central nervous system (CNS) in order to better understand the mind and to develop drugs that may have beneficial effects on neurological function. The focus of these studies has been toward the development of novel molecules, using a structure-activity relationship approach, that exhibit binding affinity at specific targets within the CNS. The merit of such studies is twofold: primarily, new compounds are produced that provide valuable scientific insight about their physiological targets, and secondarily, new synthetic methodologies that may arise in order to produce these compounds, thereby contributing to the whole of organic chemistry. As a result of the research described herein, the development of one high affinity and several moderate affinity compounds at the cannabinoid receptor subtype 1 (CB1) has been accomplished. The research demonstrates that a diaryl ether molecular scaffold represents a successful motif in the cannabinoid pharmacophore. The production of the compounds in the SAR studies also introduced a novel general synthetic methodology for the synthesis of diaryl ethers around a phloroglucinol core. A second project was initiated in order to explore the synthetic methods required to develop a general process for the synthesis of rigid aminobenzocyclobutane analogs of known phenethylamines with activity at monoaminergic neurotransmitter sites. Using the synthetic approach devised here, four novel aminobenzocyclobutane isomeric analogs of a known pharmacologically active phenethylamine, (RS)-phenylpropan-amine were synthesized and are currently being evaluated for pharmacological potential.
225

Avaliação da limpeza das paredes em canais radiculares instrumentados pelas técnicas rotatória e self-adjusting file (SAF) associadas ao uso de diferentes quelantes / Evaluation of the cleanness of root canals walls instrumented with rotary and the self-adjusting file (SAF) techniques associated with different chelators

Ferraz, José Antonio Brufato 27 April 2012 (has links)
O presente trabalho avaliou, por microscopia eletrônica de varredura (MEV), a limpeza das paredes dos canais radiculares instrumentados pelas técnicas rotatória e Self-adjusting file (SAF®) com uso do NaOCl a 1% como solução irrigadora e o uso do EDTA a 15% e da Quitosana 0,20% como soluções quelantes, e quantificou os íons cálcio removidos pelas diferentes soluções irrigadoras por meio de espectrometria de absorção atômica. Trinta dentes caninos inferiores humanos foram divididos em dois grupos (n=15), de acordo com a técnica de instrumentação utilizada: A - instrumentos FlexMaster® usados na técnica Free Tip Preparation, assegurado alargamento mínimo de 200, até o instrumento # 60.02, irrigados com 1 mL de NaOCl 1% em cada troca de instrumento e B - sistema SAF®, com prévio alargamento manual até o instrumento K #20, aplicação da SAF® por 4 minutos, com fluxo de irrigação pelo sistema VATEA de 5mL/min. Os dentes foram divididos em três subgrupos conforme a irrigação final: G1-NaOCl 1%, G2- EDTA 15% e G3 Quitosana 0,20%. Utilizou-se 5mL de cada solução à 1mL/min. A solução extravasada pelo forame foi coletada e submetida à análise espectrométrica. O EDTA 15% apresentou maior capacidade de remoção de íons cálcio do que a Quitosana a 0,20% (p<0,05) e o NaOCl 1% não removeu íons. Os espécimes foram analisados em MEV. As fotomicrografias obtidas foram avaliadas qualitativamente em relação à remoção da camada de smear observada. Não houve diferença entre as instrumentações rotatória e SAF® nos terços dos canais avaliados. Analisadas as interações entre as técnicas utilizadas e aos terços do canal, o EDTA 15% apresentou melhores resultados que a Quitosana 0,20% (p<0,05), sendo ambas as soluções melhores que o NaOCl 1%. Conclui-se que as soluções quelantes testadas foram capazes de remover íons cálcio das paredes dos canais radiculares - com superioridade do EDTA 15% sobre a Quitosana 0,20%, e o NaOCl a 1% não apresentou essa capacidade - e removeram a camada de smear das paredes dos canais radiculares com superioridade do EDTA 15%, sem interferência das técnicas de instrumentação avaliadas rotatória e SAF®. / The present study evaluated, by scanning electron microscopy (SEM), the cleanness of the root canal walls instrumented by rotary and the self-adjusting file (SAF®) techniques using 1% NaOCl as an irrigating solution and 15% EDTA, 0.20% Chitosan as chelator solutions, and quantified the calcium ions removed by the different irrigants with atomic absorption spectrometry. Thirty human mandibular canine teeth were divided into 2 groups (n=15) according to the instrumentation technique used: A- FlexMaster® instruments used with the Free tip Preparation, assuring a minimal enlargement of 200m, up to a #60 .02 instrument, irrigated with 1mL of 1% NaOCl between each instrument; and B- SAF® system, with previous enlargement to a type K #20 manual instrument, application of SAF during 4 minutes, with VATEA irrigation system at a flow of 5mL/min. The teeth were divided into three subgroups according to the final irrigation protocol: G1- 1% NaOCl, G2- 15% EDTA and G3- 0.20 % Chitosan. Five mL of solution were used at 1mL/min. The solution extruded thru the foramen was collected and submitted to spectrometric analysis. 15% EDTA showed higher calcium ion removal capacity then 0.20% Chitosan (p<0.05) and the 1% NaOCl did not remove ions. The specimens were evaluated by means of SEM. The photomicrographs obtained were qualitatively evaluated in terms of smear layer removal. There was no significant difference between the rotary and SAF® instrumentation systems in the evaluated canal thirds. The interaction techniques used and canals thirds showed that the 15% EDTA revealed better results than the 0.02% Chitosan (p<0.05), and both were better than 1% NaOCl. It can be concluded that the tested chelating solutions removed calcium ions from the root canals walls with better results for 15% EDTA than 0.20% Chitosan; 1% NaOCl did not present this capacity - and removed the smear layer form the root canal walls with better results for 15% EDTA, with no difference between the evaluated techniques rotary and SAF®.
226

Validação dos sistemas computadorizados empregados na determinação dos enantiômeros do nadolol e dos homólogos da ivermectina e da abamectina / Validation of the computer systems used in the determination of nadolol enantiomers and homologous of ivermectin and abamectin.

Alexandre, Grazielle Prado 24 November 2016 (has links)
O nadolol é um agente bloqueador de receptores &#946;-adrenérgicos empregado principalmente, na \"angina pectoris\", hipertensão, certas arritmias cardíacas e no tratamento do glaucoma (SING, 2006). A ivermectina e a abamectina são fármacos que apresentam ação antiparasitária (SHOOP, 1995). Na presente pesquisa, a cromatografia em fase líquida de alta eficiência foi uma das técnicas estudadas para a quantificação dos enantiômeros do nadolol e dos homólogos presentes na abamectina e ivermectina. A versatilidade desta técnica reside no grande número de fases estacionárias existentes, as quais possibilitam análises, separações e determinações quantitativas de uma ampla gama de compostos com alta eficiência (Aquino Neto e Nunes, 2003). Para identificação dos enantiômeros do nadolol foi utilizado o dicroísmo circular que permite a determinação da configuração absoluta de enantiômeros (LIMA, 1997). Para os enantiômeros do nadolol e dos homólogos presentes na abamectina e na ivermectina também foram realizados testes para desenvolvimento de uma metodologia de quantificação por meio de uma técnica relativamente recente chamada de eletroforese capilar (EC), a qual tem alcançado desde sua introdução um rápido desenvolvimento e ampla aplicação na análise de fármacos em medicamentos (SANTORO, 2000). Para a comprovação da qualidade e segurança dos sistemas computadorizados dos equipamentos de cromatografia em fase líquida de alta eficiência (CLAE) e de eletroforese capilar (EC) foram efetuadas, neste trabalho, as respectivas validações. Após esta validação, pode-se confirmar o correto funcionamento de um software, e suas interações com o hardware, onde devem ser levados em consideração, dentre outros, os aspectos relacionados à infra-estrutura, segurança e manutenção de dados (AGÊNCIA NACIONAL DE VIGILÂNIA SANITÁRIA, 2010). As metodologias analíticas desenvolvidas a para quantificação do nadolol, abamectina e ivermectina por cromatografia em fase líquida de alta eficiência foram validadas. A validação analítica deve garantir, por meio de estudos experimentais, que o método atenda às exigências das aplicações analíticas, assegurando a confiabilidade dos resultados. Para tanto, o método deve apresentar especificidade, linearidade, intervalo, precisão, sensibilidade, limite de quantificação e detecção, exatidão, adequados à análise (AGÊNCIA NACIONAL DE VIGILÂNIA SANITÁRIA, 2003). Portanto, o objetivo proposto nesta pesquisa é primeiramente a validação dos sistemas computadorizados dos equipamentos de cromatografia em fase líquida de alta eficiência (CLAE) e de eletroforese capilar (EC). Para isto, serão desenvolvidos e validados os métodos analíticos de separação, identificação e quantificação dos enantiômeros do nadolol e dos homólogos presentes na abamectina e na ivermectina, em medicamentos, empregando as técnicas analíticas selecionadas. / Nadolol is a blocking agent with activity in the &#946; -adrenergic receptors. It is mainly used in angina, hypertension, certain heart arrhythmias and in the treatment of glaucoma (SING, 2006). Ivermectin and abamectin are drugs with antiparasitic activity (SHOOP, 1995). In the present research, high performance liquid chromatography is one of the techniques used in the quantification of the enantiomers of nadolol and homologues present in abamectin and ivermectin. The versatility of this technique and the large number of existing stationary phases, enables the separation and quantitative determination of a wide range of compounds with high efficiency (Aquino Neto e Nunes, 2003). For identification of the nadolol enantiomers, circular dichroism was used which allows the determination of the absolute configuration of the enantiomers (LIMA, 1997). Nadolol enantiomers and the homologues present in abamectin and ivermectin will be also quantified by capillary zone electrophoresis (CE), a separation technique relatively recent, which has achieved, since its introduction, a wide application in the analysis of drugs in pharmaceutical preparations (SANTORO, 2000). In order to assure the quality of the analytical results, the computer systems of the liquid chromatograph and capillary electrophoresis equipments, must be validated prior to the analytical methods validation. Computer systems validation is used to verify and confirm the proper operation of softwares, and their interactions with the hardwares, besides the infrastructure, safety and storage of data (AGÊNCIA NACIONAL DE VIGILÂNIA SANITÁRIA, 2010). The analytical methodologies developed for quantification of nadolol, abamectin, ivermectin by using high efficiency liquid chromatography and capillary electrophoresis were validated. The analytical methods validation should ensure, through experimental studies, that the method meets the requirements for analytical applications, ensuring the reliability of the results. Parameters like, specificity, linearity, range, accuracy, sensitivity, limits of detection and quantification and accuracy, must be determined (AGÊNCIA NACIONAL DE VIGILÂNIA SANITÁRIA, 2003). The objective of this study is to validate the computer systems of the high performance liquid chromatograph and capillary electrophoresis equipments and then to develop and validate analytical methods for separation, identification and quantification of nadolol enantiomers and the homologues of abamectin and ivermectin.
227

DESENVOLVIMENTO DE UM ADESIVO PARA PRÓTESES REMOVÍVEIS CONTENDO MICROPARTÍCULAS POLIMÉRICAS DE NITRATO DE MICONAZOL: SÍNTESE E CARACTERIZAÇÃO / DEVELOPMENT OF REMOVABLE DENTURE ADHESIVE CONTAINING MICONAZOLE NITRATE-POLYMERIC MICROPARTICLES: SYNTHESIS AND CHARACTERIZATION

Molina, Andrés Felipe Cartagena 05 February 2016 (has links)
Made available in DSpace on 2017-07-24T19:21:59Z (GMT). No. of bitstreams: 1 Andres Felipe.pdf: 3893759 bytes, checksum: fd56d743b750b678334823fb1406f10a (MD5) Previous issue date: 2016-02-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The combination of well-fitting dentures with topical antifungals is appropriate therapeutic approach for denture stomatitis (EP). It was developed and evaluated an adhesive for removable dentures containing miconazole nitrate (NM) incorporated into mucoadhesive and/or pH dependent polymer microparticles aiming at increasing bioavailability. Initially, microparticles have been developed containing 10% and 20% of NM, spray-drying, using Gantrez MS-955 polymer (G10, G20), Eudragit L-100 (E10, E20) or both (EG10, EG20). An analytical method by high-performance liquid chromatography (HPLC) to quantify NM of the microparticles was validated. Microparticles were characterized by scanning electron microscopy (SEM), x-ray diffraction, Fourier-transformed infrared spectrometry (FTIR), differential scanning calorimetry (DSC), in-vitro release studies (percentage of dissolution / time, and release profiles) and antifungal activity. An experimental denture adhesive formulation (ACT) was developed containing 10% by weight of the microparticles (AE1, AG1, AEG1, AE2, AG2, AEG2) or 2% of pure drug (ANM). For all adhesives it was determined: minimum inhibitory concentration (MIC) for Candida albicans (microdilution and agar dilution); adhesive force (FA among acrylic surfaces after 0.5, 1, 3, or 6 h immersion in water); and toxicity to brine shrimp (24 h and 48 h) by calculating lethal concentration 50 (LC50). The HPLC method was proven specific, linear (r = 0.9992), precise, accurate and robust in the range 5-90 μg.mL-1, with running and retention times of 10.0 and 5.58 minutes, respectively. All microparticles showed acceptable performance (37.22% - 55.36%) and encapsulation (over 89%) values. E10 and E20 microparticles showed spherical and smooth surface, while EG20 had similar shape, but rough surface. G10, G20 and EG20 had depressed craters and morphology. The diameters of the microparticles ranged from 1.9 to 4.3 micrometers. No chemical bond was observed between the MN and the polymers through the FTIR spectra. Microencapsulation contributed to the drug amorphization, according to thermal analysis and X-ray diffraction, reducing the release time. NM and the G10, G20 and EG20 microparticles fitted the biexponential release kinetic model and the microparticles E10, E20 and EG10 fitted to mono-exponential model. The microparticles showed antifungal efficiency similar to pure drug. Extracts of the adhesives containing the microparticles and ANM showed MIC of 1.25 to 5 μg.mL-1 (comparable to Daktarin®, 2.5 μg.mL-1). Significant differences in AF for adhesive formulations evaluated as a function of immersion time in water were observed (p <0.001), with an upward trend between 1 h and 3 h, followed by reduction or stabilization up to 6 h. The incorporation of NM and polymeric microparticles did not affect the FA of the experimental adhesive and AEG20 showed the best results, with high initial values, and holding them for 6 h. All adhesive formulations showed low or no toxicity (LC50 349.53 to 931.00 μg.mL-1). The proposed denture adhesive formulation was proven compatible with the incorporation of polymeric microparticles containing NM. / A associação de próteses bem adaptadas com a presença tópica de antifúngicos é adequada abordagem terapêutica para estomatite protética (EP). Foi desenvolvido e avaliado um adesivo para prótese removível contendo nitrato de miconazol (NM) incorporado a micropartículas poliméricas muco-adesivas e/ou pH dependentes visando aumento de biodisponibilidade. Inicialmente, foram desenvolvidas micropartículas contendo 10% e 20% de NM, por spray-drying, utilizando os polímeros Gantrez MS-955 (G10, G20), Eudragit L-100 (E10, E20) ou ambos (EG10, EG20). Foi validado um método analítico por cromatografia líquida de alta eficiência (CLAE) para se quantificar NM das micropartículas. Estas foram caracterizadas por microscopia eletrônica de varredura (MEV), difração de raios x, espectrometria de infravermelho por transformada em Fourier (FTIR), calorimetria exploratória diferencial (CED), estudos de liberação in-vitro (porcentagem de dissolução/tempo e perfis de liberação) e atividade antifúngica. A seguir foram desenvolvidas formulações de um adesivo experimental para prótese (ACT) acrescido de 10% em peso das micropartículas (AE1, AG1, AEG1, AE2, AG2, AEG2) ou 2% do fármaco puro (AMN). Para todos adesivos determinou-se: concentração inibitória mínima (CMI) em Candida albicans (microdiluição em caldo e diluição em ágar); força adesiva (FA, entre superfícies acrílicas após 0,5, 1, 3, ou 6 h de imersão em água); e toxicidade em Artemia salina (24 h e 48 h), calculando-se concentração letal 50 (CL50). O método de CLAE apresentou-se específico, linear (r = 0,9992), preciso, exato e robusto na faixa de 5 a 90 μg.mL-1, com tempos de corrida e de retenção de 10,0 e 5,58 minutos, respectivamente. Todas as micropartículas mostraram aceitáveis valores de rendimento (37,22% – 55,36%) e de encapsulação (superiores a 89%). As micropartículas E10 e E20 apresentaram forma esférica e superfície lisa, enquanto EG20 possuíam a mesma forma, porém superfície rugosa. As micropartículas G10, G20 e EG20 apresentaram morfologia deprimida e crateras. Os diâmetros das micropartículas variaram entre 1,9 a 4,3 μm. Nenhuma ligação química foi observada entre o NM e os polímeros, através dos espectros de FTIR. A microencapsulação contribuiu para amorfizar o fármaco, segundo as análises térmicas e difração de raios X, reduzindo seu tempo de liberação. Ajustaram-se ao modelo cinético de liberação biexponencial o NM e as micropartículas G10, G20 e EG20, e ao modelo monoexponencial, as micropartículas E10, E20 e EG10. As micropartículas apresentaram eficiência antifúngica similar ao fármaco puro. Extratos dos adesivos contendo micropartículas e a formulação AMN apresentaram CMI entre 1,25 a 5 μg.mL-1 (comparável a Daktarin®, 2,5 μg.mL-1). Foram verificadas diferenças significativas na FA para as formulações de adesivos avaliadas em função do tempo de imersão na água (p<0,001), com tendência de aumento entre 1 h e 3 h, seguido de decréscimo ou estabilização até 6 h. A incorporação do NM e de micropartículas poliméricas não prejudicou a FA do adesivo experimental e AEG20 exibiu os melhores resultados, apresentando elevados valores iniciais, e mantendo-os por 6 h. Todas as formulações de adesivos apresentaram baixa ou nenhuma toxicidade (CL50 de 349,53 a 931,00 μg.mL-1). A formulação de adesivo para prótese removível proposta foi compatível com a incorporação de micropartículas poliméricas contendo NM.
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Validação dos sistemas computadorizados empregados na determinação dos enantiômeros do nadolol e dos homólogos da ivermectina e da abamectina / Validation of the computer systems used in the determination of nadolol enantiomers and homologous of ivermectin and abamectin.

Grazielle Prado Alexandre 24 November 2016 (has links)
O nadolol é um agente bloqueador de receptores &#946;-adrenérgicos empregado principalmente, na \"angina pectoris\", hipertensão, certas arritmias cardíacas e no tratamento do glaucoma (SING, 2006). A ivermectina e a abamectina são fármacos que apresentam ação antiparasitária (SHOOP, 1995). Na presente pesquisa, a cromatografia em fase líquida de alta eficiência foi uma das técnicas estudadas para a quantificação dos enantiômeros do nadolol e dos homólogos presentes na abamectina e ivermectina. A versatilidade desta técnica reside no grande número de fases estacionárias existentes, as quais possibilitam análises, separações e determinações quantitativas de uma ampla gama de compostos com alta eficiência (Aquino Neto e Nunes, 2003). Para identificação dos enantiômeros do nadolol foi utilizado o dicroísmo circular que permite a determinação da configuração absoluta de enantiômeros (LIMA, 1997). Para os enantiômeros do nadolol e dos homólogos presentes na abamectina e na ivermectina também foram realizados testes para desenvolvimento de uma metodologia de quantificação por meio de uma técnica relativamente recente chamada de eletroforese capilar (EC), a qual tem alcançado desde sua introdução um rápido desenvolvimento e ampla aplicação na análise de fármacos em medicamentos (SANTORO, 2000). Para a comprovação da qualidade e segurança dos sistemas computadorizados dos equipamentos de cromatografia em fase líquida de alta eficiência (CLAE) e de eletroforese capilar (EC) foram efetuadas, neste trabalho, as respectivas validações. Após esta validação, pode-se confirmar o correto funcionamento de um software, e suas interações com o hardware, onde devem ser levados em consideração, dentre outros, os aspectos relacionados à infra-estrutura, segurança e manutenção de dados (AGÊNCIA NACIONAL DE VIGILÂNIA SANITÁRIA, 2010). As metodologias analíticas desenvolvidas a para quantificação do nadolol, abamectina e ivermectina por cromatografia em fase líquida de alta eficiência foram validadas. A validação analítica deve garantir, por meio de estudos experimentais, que o método atenda às exigências das aplicações analíticas, assegurando a confiabilidade dos resultados. Para tanto, o método deve apresentar especificidade, linearidade, intervalo, precisão, sensibilidade, limite de quantificação e detecção, exatidão, adequados à análise (AGÊNCIA NACIONAL DE VIGILÂNIA SANITÁRIA, 2003). Portanto, o objetivo proposto nesta pesquisa é primeiramente a validação dos sistemas computadorizados dos equipamentos de cromatografia em fase líquida de alta eficiência (CLAE) e de eletroforese capilar (EC). Para isto, serão desenvolvidos e validados os métodos analíticos de separação, identificação e quantificação dos enantiômeros do nadolol e dos homólogos presentes na abamectina e na ivermectina, em medicamentos, empregando as técnicas analíticas selecionadas. / Nadolol is a blocking agent with activity in the &#946; -adrenergic receptors. It is mainly used in angina, hypertension, certain heart arrhythmias and in the treatment of glaucoma (SING, 2006). Ivermectin and abamectin are drugs with antiparasitic activity (SHOOP, 1995). In the present research, high performance liquid chromatography is one of the techniques used in the quantification of the enantiomers of nadolol and homologues present in abamectin and ivermectin. The versatility of this technique and the large number of existing stationary phases, enables the separation and quantitative determination of a wide range of compounds with high efficiency (Aquino Neto e Nunes, 2003). For identification of the nadolol enantiomers, circular dichroism was used which allows the determination of the absolute configuration of the enantiomers (LIMA, 1997). Nadolol enantiomers and the homologues present in abamectin and ivermectin will be also quantified by capillary zone electrophoresis (CE), a separation technique relatively recent, which has achieved, since its introduction, a wide application in the analysis of drugs in pharmaceutical preparations (SANTORO, 2000). In order to assure the quality of the analytical results, the computer systems of the liquid chromatograph and capillary electrophoresis equipments, must be validated prior to the analytical methods validation. Computer systems validation is used to verify and confirm the proper operation of softwares, and their interactions with the hardwares, besides the infrastructure, safety and storage of data (AGÊNCIA NACIONAL DE VIGILÂNIA SANITÁRIA, 2010). The analytical methodologies developed for quantification of nadolol, abamectin, ivermectin by using high efficiency liquid chromatography and capillary electrophoresis were validated. The analytical methods validation should ensure, through experimental studies, that the method meets the requirements for analytical applications, ensuring the reliability of the results. Parameters like, specificity, linearity, range, accuracy, sensitivity, limits of detection and quantification and accuracy, must be determined (AGÊNCIA NACIONAL DE VIGILÂNIA SANITÁRIA, 2003). The objective of this study is to validate the computer systems of the high performance liquid chromatograph and capillary electrophoresis equipments and then to develop and validate analytical methods for separation, identification and quantification of nadolol enantiomers and the homologues of abamectin and ivermectin.
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Avaliação da limpeza das paredes em canais radiculares instrumentados pelas técnicas rotatória e self-adjusting file (SAF) associadas ao uso de diferentes quelantes / Evaluation of the cleanness of root canals walls instrumented with rotary and the self-adjusting file (SAF) techniques associated with different chelators

José Antonio Brufato Ferraz 27 April 2012 (has links)
O presente trabalho avaliou, por microscopia eletrônica de varredura (MEV), a limpeza das paredes dos canais radiculares instrumentados pelas técnicas rotatória e Self-adjusting file (SAF®) com uso do NaOCl a 1% como solução irrigadora e o uso do EDTA a 15% e da Quitosana 0,20% como soluções quelantes, e quantificou os íons cálcio removidos pelas diferentes soluções irrigadoras por meio de espectrometria de absorção atômica. Trinta dentes caninos inferiores humanos foram divididos em dois grupos (n=15), de acordo com a técnica de instrumentação utilizada: A - instrumentos FlexMaster® usados na técnica Free Tip Preparation, assegurado alargamento mínimo de 200, até o instrumento # 60.02, irrigados com 1 mL de NaOCl 1% em cada troca de instrumento e B - sistema SAF®, com prévio alargamento manual até o instrumento K #20, aplicação da SAF® por 4 minutos, com fluxo de irrigação pelo sistema VATEA de 5mL/min. Os dentes foram divididos em três subgrupos conforme a irrigação final: G1-NaOCl 1%, G2- EDTA 15% e G3 Quitosana 0,20%. Utilizou-se 5mL de cada solução à 1mL/min. A solução extravasada pelo forame foi coletada e submetida à análise espectrométrica. O EDTA 15% apresentou maior capacidade de remoção de íons cálcio do que a Quitosana a 0,20% (p<0,05) e o NaOCl 1% não removeu íons. Os espécimes foram analisados em MEV. As fotomicrografias obtidas foram avaliadas qualitativamente em relação à remoção da camada de smear observada. Não houve diferença entre as instrumentações rotatória e SAF® nos terços dos canais avaliados. Analisadas as interações entre as técnicas utilizadas e aos terços do canal, o EDTA 15% apresentou melhores resultados que a Quitosana 0,20% (p<0,05), sendo ambas as soluções melhores que o NaOCl 1%. Conclui-se que as soluções quelantes testadas foram capazes de remover íons cálcio das paredes dos canais radiculares - com superioridade do EDTA 15% sobre a Quitosana 0,20%, e o NaOCl a 1% não apresentou essa capacidade - e removeram a camada de smear das paredes dos canais radiculares com superioridade do EDTA 15%, sem interferência das técnicas de instrumentação avaliadas rotatória e SAF®. / The present study evaluated, by scanning electron microscopy (SEM), the cleanness of the root canal walls instrumented by rotary and the self-adjusting file (SAF®) techniques using 1% NaOCl as an irrigating solution and 15% EDTA, 0.20% Chitosan as chelator solutions, and quantified the calcium ions removed by the different irrigants with atomic absorption spectrometry. Thirty human mandibular canine teeth were divided into 2 groups (n=15) according to the instrumentation technique used: A- FlexMaster® instruments used with the Free tip Preparation, assuring a minimal enlargement of 200m, up to a #60 .02 instrument, irrigated with 1mL of 1% NaOCl between each instrument; and B- SAF® system, with previous enlargement to a type K #20 manual instrument, application of SAF during 4 minutes, with VATEA irrigation system at a flow of 5mL/min. The teeth were divided into three subgroups according to the final irrigation protocol: G1- 1% NaOCl, G2- 15% EDTA and G3- 0.20 % Chitosan. Five mL of solution were used at 1mL/min. The solution extruded thru the foramen was collected and submitted to spectrometric analysis. 15% EDTA showed higher calcium ion removal capacity then 0.20% Chitosan (p<0.05) and the 1% NaOCl did not remove ions. The specimens were evaluated by means of SEM. The photomicrographs obtained were qualitatively evaluated in terms of smear layer removal. There was no significant difference between the rotary and SAF® instrumentation systems in the evaluated canal thirds. The interaction techniques used and canals thirds showed that the 15% EDTA revealed better results than the 0.02% Chitosan (p<0.05), and both were better than 1% NaOCl. It can be concluded that the tested chelating solutions removed calcium ions from the root canals walls with better results for 15% EDTA than 0.20% Chitosan; 1% NaOCl did not present this capacity - and removed the smear layer form the root canal walls with better results for 15% EDTA, with no difference between the evaluated techniques rotary and SAF®.
230

GLYCOSAMINOGLYCAN LYASES IN THE PREPARATION OF OLIGOSACCHARIDES

Alabbas, Alhumaidi B 01 January 2018 (has links)
Glycosaminoglycans are heterogeneous polysaccharides that mediate important biological functions. There has been considerable interest in deciphering the precise GAG sequences that are responsible for protein interactions. In fact, several GAG oligosaccharides have been discovered to date as targeting proteins with higher level of specificity. Yet, it has been difficult to develop GAG oligosaccharides as drugs. One of the key reasons for this state of art is that GAG synthesis is extremely challenging and is highly structure-specific. Thus, much of the biology and pharmacology of GAG remains unknown and unexploited to date. An alternative approach is to prepare GAG oligosaccharides using enzymatic depolymerization of polymeric GAGs. GAG lyases, including heparinases and chondritinases represent powerful tools that can theoretically generate multiple oligosaccharides in parallel. However, it is difficult to implement such procedures with high consistency. Moreover, GAG lyases can digest GAGs down to disaccharides. A priori, non-polymeric GAGs, or alternatively GAG oligosaccharides containing 4 to 10 residues, would be expected to function better as therapeutic agents because they would be more homogeneous and less non-specific than their polymeric precursors. Thus, we reasoned that immobilization of these enzymes may engineer altered biopolymer processing, which may afford longer oligosaccharides in higher proportions and greater consistency. Heparinase-I and chondroitinase ABC were immobilized on CNBr-activated Sepharose and compared with the free form of the enzyme. Immobilized GAG lyases retained high efficiency of depolymerization over a wide range of pH, temperature and reusability. Most importantly, the immobilized enzyme was found to produce larger proportions of oligosaccharides longer than di- and tetra-saccharides as compared to lyases in the free form. A two dimensional separation involves size exclusion chromatography followed by reversed phase ion-pairing ultra performance liquid chromatography coupled to electrospray ionization mass spectrometry was employed to separate and characterize oligosaccharide structures. We have identified 40 heparin oligosaccharides, including regular and rare structures ranging from dp4 to dp10 and 39 chondroitin sulfate oligosaccharides in high homogeneity and significant yields. Overall, this technology is likely to offer a simple and cost effective route to preparation of larger amounts of sequences that can be expected to bind and modulate protein function.

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