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Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2012. / Chirality is very important to the pharmaceutical industry as enantiomers have the same macroproperties except for their optical and pharmacological activity. Industrial research has thus focused to find the most effective resolution technique. However, our aim was to obtain more information regarding the discrimination process. In this project the structures of the hydrates of diquininium L-malate, (2QUIN+)(L-MA2-)·2H20 and the di-quininium O-malate, (2QUIN+)(D-MA2-)·2H20 have been investigated. (-)-Quinine (QUIN) did not show selectivity between the 0 and L malic acid and the structure of (2QUIN+)(DL-MA2-)·2H20 was obtained. Effect of solvents was demonstrated in the study and the structure of (QUIN+)(D-MA-)·H20) was reported. The relationship between C-O bonds of the carboxylate and carboxylic moieties and L'lpKa was explored in salt and co-crystal formation. Kinetics of absorption was conducted for the reaction of (+)-deoxycholic acid (DCA) with npropylamine and DCA with racemic sec-butylamine. The rate constants of the reactions were determined. Kinetics of desolvation was performed on the powder samples of mixtures of DCA and sec-butylamine and DCA with di-n-butylamine. Non-isothermal methods were used where a series of TG analyses was carried out at different heating rates (2, 4, 10, 32 K rnin'). The structures of DCA with n-propylamine and di-n-butylamine were elucidated. The selectivity of DCA was investigated. The host compound was found to be able to successfully resolve racemic sec-butylamine (2-BUAM) and 2-amino-3-methylbutane (MeBUAM). The structures of DCA with enantiomers of these guests are reported in the study. The structures of RBUAM and S-BUAM were solved in different space groups while R-MeBUAM and S-MeBUAM crystallized in the same space group.

Resumo: Não disponível / Abstract: Upper aero digestive tract (UADT) cancer is an important cause of morbidity and mortality worldwide. Chronic alcohol intake and dietary deficiency zinc, tobacco smoking, and gastroesophageal reflux disease are the major risk factors to the UADT cancer. In the present study, we utilized a diet that mimic inadequate zinc intake (Zn-) diet and supplemented it with unconjugated bile deoxycholic acid (DCA), a component associated with gastroesophageal reflux disease and high fat diets. The aim of this study was to assess the additional influence of exposure to cigarette smoke and ethanol intake on the epithelial alterations of the esophagus and tongue induced by Zn-+DCA diet. Male C57BL/6 mice animals were allocated into six groups: Groups 1 to 3 were fed modified diet (Zn-+ 0.2% DCA) and groups 4 to 6 were fed control diet. After 5-weeks, groups 2 and 5 intake ethanol 10% ad libitum and groups 3 and 6 were exposed to cigarette smoke for 15 weeks. All animals were euthanized at the end of week 20 and tongue and esophagus were collected for histological analysis and immunohistochemical analysis of cell proliferation using Ki- 67 marker and cyclooxygenase 2 expression (COX-2). The Zn-+DCA diet treatment trend to increased cell proliferation indexes and the incidence of hyperkeratosis in the tongue and esophagus but not in COX-2 expression. No additional effect of 15-week treatment with ethanol or cigarette smoke was observed. These findings indicate that dietary zinc deficiency supplemented with deoxycolic acid appears to be an important factor of epithelial aggression and that deleterious effect of ethanol and cigarette smoke could be detected in a long-term exposure. / Orientador: Luis Fernando Barbisan / Coorientador: Maria Aparecida Marchesan Rodrigues / Banca: Noeme Souza Rocha / Banca: Luis Antonio Justulin Junior / Mestre

Made available in DSpace on 2014-06-11T19:27:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-25Bitstream added on 2014-06-13T19:36:16Z : No. of bitstreams: 1 zapaterini_jr_me_botfm.pdf: 761331 bytes, checksum: 08585432398fc143a257f8a9980a9d56 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Upper aero digestive tract (UADT) cancer is an important cause of morbidity and mortality worldwide. Chronic alcohol intake and dietary deficiency zinc, tobacco smoking, and gastroesophageal reflux disease are the major risk factors to the UADT cancer. In the present study, we utilized a diet that mimic inadequate zinc intake (Zn-) diet and supplemented it with unconjugated bile deoxycholic acid (DCA), a component associated with gastroesophageal reflux disease and high fat diets. The aim of this study was to assess the additional influence of exposure to cigarette smoke and ethanol intake on the epithelial alterations of the esophagus and tongue induced by Zn-+DCA diet. Male C57BL/6 mice animals were allocated into six groups: Groups 1 to 3 were fed modified diet (Zn-+ 0.2% DCA) and groups 4 to 6 were fed control diet. After 5-weeks, groups 2 and 5 intake ethanol 10% ad libitum and groups 3 and 6 were exposed to cigarette smoke for 15 weeks. All animals were euthanized at the end of week 20 and tongue and esophagus were collected for histological analysis and immunohistochemical analysis of cell proliferation using Ki- 67 marker and cyclooxygenase 2 expression (COX-2). The Zn-+DCA diet treatment trend to increased cell proliferation indexes and the incidence of hyperkeratosis in the tongue and esophagus but not in COX-2 expression. No additional effect of 15-week treatment with ethanol or cigarette smoke was observed. These findings indicate that dietary zinc deficiency supplemented with deoxycolic acid appears to be an important factor of epithelial aggression and that deleterious effect of ethanol and cigarette smoke could be detected in a long-term exposure.

Thesis submitted in fulfilment of the requirements for the degree Magister Technologiae: Chemistry in the Faculty of Applied Science at the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY 2012 / Chirality is very important to the pharmaceutical industry as enantiomers have the same macroproperties except for their optical and pharmacological activity. Industrial research has thus focused to find the most effective resolution technique. However, our aim was to obtain more information regarding the discrimination process. In this project the structures of the hydrates of di-quininium L-malate, (2QUIN+)(L-MA2-)•2H2O and the di-quininium D-malate, (2QUIN+)(D-MA2-)•2H2O have been investigated. (-)-Quinine (QUIN) did not show selectivity between the D and L malic acid and the structure of (2QUIN+)(DL-MA2-)•2H2O was obtained. Effect of solvents was demonstrated in the study and the structure of (QUIN+)(D-MA-)•H2O) was reported. The relationship between C-O bonds of the carboxylate and carboxylic moieties and ÄpKa was explored in salt and co-crystal formation. Kinetics of absorption was conducted for the reaction of (+)-deoxycholic acid (DCA) with n-propylamine and DCA with racemic sec-butylamine. The rate constants of the reactions were determined. Kinetics of desolvation was performed on the powder samples of mixtures of DCA and sec-butylamine and DCA with di-n-butylamine. Non-isothermal methods were used where a series of TG analyses was carried out at different heating rates (2, 4, 10, 32 K min-1). The structures of DCA with n-propylamine and di-n-butylamine were elucidated. The selectivity of DCA was investigated. The host compound was found to be able to successfully resolve racemic sec-butylamine (2-BUAM) and 2-amino-3-methylbutane (MeBUAM). The structures of DCA with enantiomers of these guests are reported in the study. The structures of R-BUAM and S-BUAM were solved in different space groups while R-MeBUAM and S-MeBUAM crystallized in the same space group.

Targeted drug delivery to the brain is difficult to achieve using conventional techniques, largely due to the blood-brain barrier’s (BBB) impediment to drug diffusion into the brain parenchyma. In response, development of convection-enhanced delivery (CED) offers the ability to circumvent the BBB and target specific areas of the brain. Predictability of infusate movement in pathological brain states during CED will maximize the effectiveness of this treatment, and therefore modeling of infusate movement must be characterized. Previous work from our lab effectively modeled CED in rats using the middle carotid artery occlusion model of cytotoxic edema. However, previous models examined for vasogenic edema study did not show pure vasogenic edema. The purpose of this study was to develop a model of pure vasogenic edema in the rat brain. In this study, we show that stereotactic 9 µL infusion of 1.0 mM DCA over 45 minutes into the rat corpus callosum reproducibly creates pure vasogenic edema, as observed in the peritumoral white matter surrounding gliomas.

Deoxycholic acid (DCA) is a secondary bile acid postulated to be involved in the etiology and the progression of colorectal cancer, but its specific mechanisms are not fully understood. DCA has been shown to induce apoptosis allowing selection for apoptosis-resistant cells, which highlights the importance of understanding the mechanisms of action of DCA. Previously, it has been demonstrated that DCA perturbs the plasma membrane, leading to the activation of receptor tyrosine kinases. Because the insulin-like growth factor-1 receptor (IGF-IR), a receptor tyrosine kinase, is demonstrated to play a significant role in protecting colorectal cancer cells from apoptosis, we hypothesized that DCA modulates IGF-IR functions in colorectal cancer cells. We demonstrated that DCA induced the dynamin-dependent endocytosis of IGF-IR through both clathrin-mediated and caveolin-1-dependent mechanisms. Endocytosis of IGF-IR sensitized cells to DCA-induced apoptosis, which demonstrated that IGF-IR played a role in protecting cells against DCA-induced apoptosis. Since DCA-induced endocytosis of IGF-IR was determined to be a caveolin-1 dependent process, caveolin-1 knockdown in HCT116 (HCT116-Cav1-AS) prevented the DCA-mediated endocytosis of IGF-IR. However, we observed an increased sensitivity of DCA-induced apoptosis in the Cav1-AS cells. This suggested that caveolin-1 knockdown altered the plasma membrane dynamics such that although IGF-IR was maintained at the plasma membrane, it facilitated a pro-apoptotic signal. We demonstrated that DCA induced the activation of the pro-apoptotic p38 signaling pathway in HCT116-Cav1-AS, but not in HCT116-Mock, via IGF-IR. Inhibition of both the IGF-IR and p38 independently in HCT116-Cav1-AS significantly decreased their sensitivity to DCA-induced apoptosis. These observations demonstrated that, in a caveolin-1 dependent manner, IGF-IR played a dynamic role in the DCA-mediated apoptosis. Finally, we provided preliminary evidence demonstrating that autophagy played a central role in protecting DCA-resistant cells from DCA-induced apoptosis.Since resistance to DCA also confers apoptosis-resistance, understanding the mechanisms that lead to or prevent DCA-induced cell death is significant, since they can lead to the development of novel therapeutic strategies to sensitize apoptosis-resistant colorectal cancer cells to undergo cell death.

<p>Mnogi lekovi registrovani za razne druge indikacije mogu da deluju selektivno na tumorske receptore, signalne puteve, metaboličke procese, bioenergetske faktore, enzime, proteine, gene koji reguli&scaron;u proliferaciju, apoptozu i neoangiogenezu tumora ne pogađajući ove procese kod zdravih ćelija. Uvođenje novih lekova je izrazito dug, složen i skup proces istraživanja. Kori&scaron;ćenjem principa otkrivanja antikancerskog efekta kod već registrovanih lekova za druge indikacije, direktno se utiče na skraćivanje vremena i tro&scaron;kova istraživanja. Eksperimentalno je ispitana efikasnost antitumorskog delovanja mebendazola, metformina, itrakonazola, diklofenaka, nitroglicerina i deoksiholne kiseline na fibrosarkom hrčka izazvan BHK21/C13 tumorskom ćelijskom linijom praćenjem veličine i histologije lečenih tumora. Eksperimentalno je ispitana mogućnost primene deoksiholne kiseline, nitroglicerina, kofeina i itrakonazola kao adjuvansa u kombinaciji sa pojedinim ispitivanim lekovima (metformin, itrakonazol, diklofenak) za lečenje fibrosarkoma hrčka. Kako je ispitivanje vr&scaron;eno na mladuncima imladim hrčkovima i kako su sarkomi najče&scaron;ći u dečijem uzrastu, definisanje potencijalne antikancerske uloge ispitivanih lekova se odnosi prvenstveno na njihovu primenu u pedijatriji. Pokazano je da metformin, kombinacije metformina sa kofeinom, metformina sa itrakonazolom i metformina sa nitroglicerinom deluju u pogledu svih ispitivanih parametara tumora antitumorski na fibrosarkom hrčka. Kofein, itrakonazol i nitroglicerin pojačavaju antitumorsko dejstvo metformina na fibrosarkom hrčka. Tokom svih eksperimenata realizovanih u okviru ove disertacije, pokazalo se da nije bilo delotvornog tretmana, koji ne sadrži metformin.</p> / <p>Many drugs registered for various other indications can act selectively to tumor receptors, signaling pathways, metabolic processes, bioenergetic factors, enzymes, proteins, genes that regulate proliferation, apoptosis, and neoangiogenesis of the tumor without affecting these processes in the healthy cells. The introduction of new drugs is a very long, complex and expensive process of research. Using the principle of detecting the anticancer effect in already registered drugs for other indications, directly affects the reduction of time and cost of research. The efficacy of mebendazole, metformin, itraconazole, diclofenac, nitroglycerin and deoxycholic acid antitumor activity on hamster fibrosarcinoma induced experimentally by the BHK21/C13 tumor cell line was tested by monitoring the size and histology of the treated tumors. The possibility of using deoxycholic acid, nitroglycerin, caffeine and itraconazole as an adjuvant in combination with investigated drugs (metformin, itraconazole, diclofenac) for the treatment of hamster fibrosarcoma has been experimentally tested. As the examination was carried out on young cubs and young hamsters and that sarcomas are the most common in childhood, defining the potential anti-cancer role of the investigated drugs relates primarily to their application in pediatrics. Metformin, combinations of metformin with caffeine, metformin with itraconazole and metformin with nitroglycerin have shown antitumor action on the hamster fibrosarcoma in terms of all tested tumor parameters. Caffeine, itraconazole and nitroglycerin increase the antitumor effect of metformin on the hamster fibrosarcoma. During all the experiments carried out within this dissertation, there has been no effective treatment, which does not contain metformin.</p>

<p>Raloksifen je predstavnik selektivnih modulatora estrogenih receptora koji se koristi u terapiji osteoporoze i invazivnog oblika raka dojke u postmenopauzi. Raloksifen se relativno dobro resorbuje iz gastrointestinalnog trakta, ali pri prvom prolasku kroz jetru podleže biotransformaciji u značajnom procentu, &scaron;to je uzrok njegove niske biolo&scaron;ke raspoloživosti. Bioraspoloživost kod ljudi iznosi 2%, a kod Wistar pacova 39%. Različite supstance se koriste da bi se pobolj&scaron;ala bioraspoloživost lekova. Žučne kiseline, kao &scaron;to je deoksiholna kiselina, omogućavaju bolji prolazak kroz biolo&scaron;ke membrane drugim supstancama, te mogu povećati bioraspoloživost lekova. Apigenin je &scaron;iroko rasprostranjeni flavonoid koji inhibi&scaron;e različite metaboličke puteve i na taj način može usporiti metabolizam i eliminaciju i povećati koncentraciju lekova u krvi. Ciljevi ovog istraživanja su bili da se ispita da li apigenin i natrijum-deoksiholat mogu povećati bioraspoloživost raloksifena, njihov uticaj na biohemijske parametre i parametre hemostaze, kao i da se ispita antioksidativni potencijal apigenina. Ispitan je i uticaj apigenina na akutno o&scaron;tećenje jetre usled primene toksične doze paracetamola. U istraživanju su kori&scaron;ćeni zdravi, beli pacovi mu&scaron;kog roda, soja Wistar. U ogledu su ukupno kori&scaron;ćene 84 eksperimentalne životinje. Sva ispitivanja na životinjama je odobrila Etička komisija Univerziteta u Novom Sadu. Raloksifen je primenjen intravenski i per os, dok su natrijum-deoksiholat i apigenin aplikovani peroralno. Uzorci krvi, urina i fecesa su kori&scaron;ćeni za određivanje farmakokinetskih parametara, dok su za određivanje biohemijskih, hemostatskih i parametara oksidativnog stresa kori&scaron;ćeni serum i uzorci jetre laboratorijskih životinja. Pretretman natrijum-deoksiholatom je doveo do smanjenja koncentracije raloksifena u krvi zbog olak&scaron;anog i brzog prodora raloksifena u periferne kompartmane. Time je značajno produženo poluvreme eliminacije i srednje vreme zadržavanja raloksifena i značajno je povećan volumen distribucije raloksifena. Apigenin je doveo do manjeg pada koncentracije raloksifena u prvim satima nakon intravenske primene raloksifena, dok su koncentracije raloksifena bile značajno vi&scaron;e nakon osmog časa od primene leka. Uticaj raloksifena na biohemijske parametre je bio značajno veći nakon intravenske nego nakon peroralne primene. Nakon intravenske primene raloksifena je značajno povećana aktivnost enzima jetre, ALP, ALT, AST i GGT, dok su pokazatelji funkcije bubrega, urea, mokraćna kiselina i kreatinin bili sniženi. U grupama koje su pretretirane natrijum-deoksiholatom i apigeninom vrednosti ovih parametara bile su niže u odnosu na grupu tretiranu samo raloksifenom. Statistički najznačajniji uticaj je imala primena trojne kombinacije, raloksifena, natrijum-deosiholata i apigenina, koja je dovela do značajnog pada aktivnosti enzima jetre, i u odnosu na grupu tretiranu raloksifenom i u odnosu na kontrolnu grupu. Kod životinja tretiranih kombinacijom apigenina i paracetamola pokazatelji toksičnosti su bili značajno niži, naročito vrednosti ALT i ALP, u odnosu na grupu koja je dobijala samo paracetamol. Hepatotoksičnost izazvana toksičnom dozom paracetamola je potvrđena i histopatolo&scaron;kim promenama na jetri, koje nisu primećene u grupi životinja tretiranih kombinacijom apigenina i paracetamola. Ispitivanjem je utvrđeno da apigenin može da spreči paracetamolom indukovano povećanje nivoa MDA, &scaron;to ukazuje da apigenin pozitivno utiče na očuvanje integriteta ćelije. Aktivnost enzima CAT i GR u homogenatima jetre je bila značajno povećana nakon primene toksične doze paracetamola u odnosu na kontrolnu grupu. Aktivnost enzima CAT i GR u grupi tretiranoj kombinacijom apigenina i paracetamola je bila približna vrednostima u kontrolnoj grupi. Na osnovu rezultata istraživanja može se zaključiti da natrijum-deoksiholat i apigenin značajno utiču na farmakokinetiku raloksifena. Primena natrijum-deoksiholata dovela je do pada koncentracije raloksifena u krvi, značajnog prelaska raloksifena iz krvi u periferne kompartmane i povećanja njegovog volumena distribucije, dok je apigenin značajno usporio metabolizam i eliminaciju raloksifena i doveo do njegovog produženog zadržavanja u krvi. Natrijum-deoksiholat i apigenin su pokazali pozitivan uticaj na biohemijske parametre, parametre hemostaze i smanjenje nivoa oksidativnog stresa. Kombinacija natrijum-deoksiholata i apigenina je pokazala sinergistički uticaj na navedene parametre, odnosno dovela je do značajnih promena u odnosu na pojedinačnu primenu ovih supstanci. Rezultati ispitivanja ukazuju na to da apigenin smanjuje stepen lipidne peroksidacije i da dovodi do značajnog povećanja enzimskih antioksidantnih mehanizama odbrane kod pacova kod kojih je hepatotoksičnost indukovana paracetamolom.</p> / <p>Raloxifene is selective estrogen receptor modulator used in treatment of osteoporosis and invasive breast cancer in postmenopausal women. Raloxifene is well absorbed from the gastrointestinal tract, but undergoes extensive first-pass metabolism, which results in very low bioavailability of raloxifene, 2% in humans, and 39% in Wistar rats. Various supstances are used for increasing bioavailability of other drugs. Bile acids, such as deoxycholic acid, promote transport of other supstances through biological membranes, and consequently, may increase their bioavailability. Apigenin is a widespread flavonoid, which inhibits different metabolic pathways. Thus, apigenin can slow down metabolism and elimination of drugs, and raise drug concentration in blood. Aims of this study were to investigate if apigenin and sodium deoxycholate could increase bioavailability of raloxifene, their influence on biochemical and hemostasis parameters, and to investigate antioxidative potential of apigenin. Furthermore, influence of apigenin on acute liver damage after toxic dose of paracetamol was examined. In vivo experiments were performed on 84 laboratory healthy male Wistar rats. All experiments were approved by Ethics Committee of University of Novi Sad. Raloxifene was applied intravenously and per os, while sodium deoxycholate and apigenin were given perorally. Blood, urine and feces samples were used for pharmacokinetic parameters measurement, whereas serum and liver samples were used for evaluation of biochemical, hemostasis and oxidative stress parameters. Pretreatment of sodium deoxycholate led to raloxifene blood concentration decrease due to easier penetration of raloxifene in peripher compartments. As a result, raloxifene half-life and mean residence time were significantly longer and volume of distribution was increased. Apigenin caused lower decrease in raloxifene concentration in first few hours after raloxifene intravenous application, while raloxifene concentrations after apigenin pretreatment were significantlny higher 8 hours after raloxifene application. Influence of raloxifene on biochemical parameters was more significant after intravenous than after per os application. Intravenous application of raloxifene led to increased activity of liver enzymes, ALP, ALT, AST and GGT, while parameters of kidney function, urea, uric acid and creatinine were decreased in comparison to the control group. In experimental groups pretreated with sodium deoxycholate and apigenin these parameters were lower than in the group treated only with raloxifene. Statistically the most significant effects were in the group treated with combination of raloxifene, sodium deoxycholate and apigenin, which caused significant decrease in activity of liver enzymes compared both with raloxifene and control group of animals. In experimental animals treated with combination of apigenin and paracetamol bioindicators of paracetamol toxicity were significantly lower, especially activity of ALT and ALP, in comparison to the group treated only with paracetamol. Hepatotoxicity induced by toxic dose of paracetamol was also confirmed by histopathological alterations in liver, which were not observed in the experimental group treated with combination of apigenin and paracetamol. In this study it was confirmed that apigenin could prevent paracetamol-induced MDA level increase, which suggests that apigenin have positive effects on cell integrity. Activity of CAT and GR in liver homogenates was significantly increased after toxic dose of paracetamol in comparison to the control group, while activity of these enzymes in the group treated with apigenin and paracetamol was similar to values in the control group. Results of this study showed that sodium deoxycholate and apigenin can significantly change pharmacokinetic parameters of raloxifene. Sodium deoxycholate caused signicant decrease in raloxifene blood concentration, extensive distribution from blood to peripheral compartments and increase of raloxifene volume of distribution. Apigenin inhibited metabolism and elimination of raloxifene and thus prolonged half-life and mean residence time of raloxifene. Sodium deoxycholate and apigenin showed positive effects on biochemical and hemostasis parameters and decreased the level oxidative stress. Combination of sodium deoxycholate and apigenin showed synergistic effects on these parameters in comparison to effects of separate application of sodium deoxycholate and apigenin. The result of our study indicates that apigenin inhibits the level of lipid peroxidation and significantly increase the enzyme antioxidant defence mehanisms in paracetamol induced hepatotoxicity in rats.</p>