• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 54
  • 20
  • 8
  • 5
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 114
  • 42
  • 17
  • 17
  • 16
  • 14
  • 13
  • 13
  • 12
  • 12
  • 11
  • 11
  • 10
  • 10
  • 10
  • 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.
101

Metodologia analítica aplicada ao controle de qualidade do antifúngico cloridrato de butenafina na forma de creme e à avaliação da sua penetração cutânea in vitro / Analytical methodology applied to the quality control of the antifungal butenafine hydrochloride in cream formulation and to the analysis of its penetration in vitro

Barth, Aline Bergesch January 2010 (has links)
Objetivos: os objetivos gerais deste trabalho foram desenvolver, validar e comparar métodos indicativos de estabilidade para a análise do cloridrato de butenafina (BTF), matéria-prima e forma farmacêutica, bem como determinar a cinética de degradação do fármaco em condição de estresse. Adicionalmente, o trabalho visou à validação de método para avaliar e comparar a penetração/permeação cutânea da BTF de diferentes formulações. Métodos: Um método indicativo de estabilidade para análise da BTF por cromatografia líquida de alta eficiência (CLAE) foi desenvolvido e validado, conforme normas do ICH. A cinética de degradação do fármaco (matériaprima e creme) frente à luz UVC foi determinada. Testes para o desenvolvimento de método quantitativo por eletroforese capilar para a análise do fármaco isoladamente e presente na formulação foram realizados. O método analítico cromatográfico previamente desenvolvido para a formulação semi-sólida foi validado para a quantificação de BTF na pele suína. Em seguida, as penetrações/permeações cutâneas do fármaco utilizando células de Franz foram analisadas visando à comparação de duas formulações comerciais (uma delas brasileira e a outra americana). Resultados e Conclusões: O método de CLAE indicativo de estabilidade desenvolvido demonstrou ser adequado para a determinação da substância ativa na formulação mesmo na presença de produtos de degradação, bem como para a quantificação do fármaco na pele suína e no fluído receptor. Os principais fatores extrínsecos que promovem a degradação do fármaco foram estabelecidos: luz, oxidação e meio básico (este último somente na presença de excipientes). A determinação da cinética de fotodegradação como sendo de primeira ordem demonstra que o processo é dependente da concentração do fármaco, reforçando a necessidade de proteção frente à luz. Já o método por eletroforese capilar mostrou-se não específico frente à formulação placebo simulado, inviabilizando seu uso para o creme. Na avaliação da permeação cutânea das formulações brasileira e americana não foi detectada presença considerável do fármaco no fluído receptor para ambos os produtos. Já na verificação da penetração, não houve diferença significativa na retenção do fármaco na epiderme, entretanto, na derme a diferença foi estatisticamente significativa, com maior concentração retida na análise da formulação americana (α = 0,05). / Objectives: The aim of the present work was to develop, validate and compare stability indicating methods to quantify butenafine hydrochloride (BTF), raw material and commercial cream, as well as to establish the degradation kinetics of the drug in a stress condition. Also, the study had the goal of validating a method to assess and compare the cutaneous permeation/penetration of two different formulations. Methods: A stability-indicating method for the analysis of BTF by high performance liquid chromatography (HPLC) was developed and validated according to the ICH guidelines. The degradation kinetics of the drug (raw material and cream) under the UVC light was determined. Analyzes to develop and validate an analytical method by capillary electrophoresis, to quantify the drug by itself and in the cream, were performed. The chromatographic method previously developed for the semi-solid product was validated to quantify the drug in porcine skin. Then, the cutaneous permeation/penetration of BTF, through the Franz-type cell, was analyzed to compare two different commercial formulations (one of them is Brazilian and the other is American). Results and Conclusions: The developed stability-indicating method was adequate to determine the active substance in the formulation even in the presence of the degradation products, as well as to quantify the drug in porcine skin and in the receptor fluid. The main extrinsic factors that promote the drug degradation were established: light, oxidative and basic media (the last in the presence of the excipient ingredients). The photodegradation kinetics was determined as first order showing that the process is dependent on the drug concentration, reaffirming the necessity of protection against light. The method by capillary electrophoresis was not specific considering the placebo formulation, hindering its use to the cream. During the cutaneous permeation analysis, no drug was found in the receptor media of both the Brazilian and the American formulations. No difference was verified to the epidermis, although to the dermis there was a statistical distinction as the concentration of retained drug from the American formulation was higher (α = 0,05).
102

Metodologia analítica aplicada ao controle de qualidade do antifúngico cloridrato de butenafina na forma de creme e à avaliação da sua penetração cutânea in vitro / Analytical methodology applied to the quality control of the antifungal butenafine hydrochloride in cream formulation and to the analysis of its penetration in vitro

Barth, Aline Bergesch January 2010 (has links)
Objetivos: os objetivos gerais deste trabalho foram desenvolver, validar e comparar métodos indicativos de estabilidade para a análise do cloridrato de butenafina (BTF), matéria-prima e forma farmacêutica, bem como determinar a cinética de degradação do fármaco em condição de estresse. Adicionalmente, o trabalho visou à validação de método para avaliar e comparar a penetração/permeação cutânea da BTF de diferentes formulações. Métodos: Um método indicativo de estabilidade para análise da BTF por cromatografia líquida de alta eficiência (CLAE) foi desenvolvido e validado, conforme normas do ICH. A cinética de degradação do fármaco (matériaprima e creme) frente à luz UVC foi determinada. Testes para o desenvolvimento de método quantitativo por eletroforese capilar para a análise do fármaco isoladamente e presente na formulação foram realizados. O método analítico cromatográfico previamente desenvolvido para a formulação semi-sólida foi validado para a quantificação de BTF na pele suína. Em seguida, as penetrações/permeações cutâneas do fármaco utilizando células de Franz foram analisadas visando à comparação de duas formulações comerciais (uma delas brasileira e a outra americana). Resultados e Conclusões: O método de CLAE indicativo de estabilidade desenvolvido demonstrou ser adequado para a determinação da substância ativa na formulação mesmo na presença de produtos de degradação, bem como para a quantificação do fármaco na pele suína e no fluído receptor. Os principais fatores extrínsecos que promovem a degradação do fármaco foram estabelecidos: luz, oxidação e meio básico (este último somente na presença de excipientes). A determinação da cinética de fotodegradação como sendo de primeira ordem demonstra que o processo é dependente da concentração do fármaco, reforçando a necessidade de proteção frente à luz. Já o método por eletroforese capilar mostrou-se não específico frente à formulação placebo simulado, inviabilizando seu uso para o creme. Na avaliação da permeação cutânea das formulações brasileira e americana não foi detectada presença considerável do fármaco no fluído receptor para ambos os produtos. Já na verificação da penetração, não houve diferença significativa na retenção do fármaco na epiderme, entretanto, na derme a diferença foi estatisticamente significativa, com maior concentração retida na análise da formulação americana (α = 0,05). / Objectives: The aim of the present work was to develop, validate and compare stability indicating methods to quantify butenafine hydrochloride (BTF), raw material and commercial cream, as well as to establish the degradation kinetics of the drug in a stress condition. Also, the study had the goal of validating a method to assess and compare the cutaneous permeation/penetration of two different formulations. Methods: A stability-indicating method for the analysis of BTF by high performance liquid chromatography (HPLC) was developed and validated according to the ICH guidelines. The degradation kinetics of the drug (raw material and cream) under the UVC light was determined. Analyzes to develop and validate an analytical method by capillary electrophoresis, to quantify the drug by itself and in the cream, were performed. The chromatographic method previously developed for the semi-solid product was validated to quantify the drug in porcine skin. Then, the cutaneous permeation/penetration of BTF, through the Franz-type cell, was analyzed to compare two different commercial formulations (one of them is Brazilian and the other is American). Results and Conclusions: The developed stability-indicating method was adequate to determine the active substance in the formulation even in the presence of the degradation products, as well as to quantify the drug in porcine skin and in the receptor fluid. The main extrinsic factors that promote the drug degradation were established: light, oxidative and basic media (the last in the presence of the excipient ingredients). The photodegradation kinetics was determined as first order showing that the process is dependent on the drug concentration, reaffirming the necessity of protection against light. The method by capillary electrophoresis was not specific considering the placebo formulation, hindering its use to the cream. During the cutaneous permeation analysis, no drug was found in the receptor media of both the Brazilian and the American formulations. No difference was verified to the epidermis, although to the dermis there was a statistical distinction as the concentration of retained drug from the American formulation was higher (α = 0,05).
103

Metodologia analítica aplicada ao controle de qualidade do antifúngico cloridrato de butenafina na forma de creme e à avaliação da sua penetração cutânea in vitro / Analytical methodology applied to the quality control of the antifungal butenafine hydrochloride in cream formulation and to the analysis of its penetration in vitro

Barth, Aline Bergesch January 2010 (has links)
Objetivos: os objetivos gerais deste trabalho foram desenvolver, validar e comparar métodos indicativos de estabilidade para a análise do cloridrato de butenafina (BTF), matéria-prima e forma farmacêutica, bem como determinar a cinética de degradação do fármaco em condição de estresse. Adicionalmente, o trabalho visou à validação de método para avaliar e comparar a penetração/permeação cutânea da BTF de diferentes formulações. Métodos: Um método indicativo de estabilidade para análise da BTF por cromatografia líquida de alta eficiência (CLAE) foi desenvolvido e validado, conforme normas do ICH. A cinética de degradação do fármaco (matériaprima e creme) frente à luz UVC foi determinada. Testes para o desenvolvimento de método quantitativo por eletroforese capilar para a análise do fármaco isoladamente e presente na formulação foram realizados. O método analítico cromatográfico previamente desenvolvido para a formulação semi-sólida foi validado para a quantificação de BTF na pele suína. Em seguida, as penetrações/permeações cutâneas do fármaco utilizando células de Franz foram analisadas visando à comparação de duas formulações comerciais (uma delas brasileira e a outra americana). Resultados e Conclusões: O método de CLAE indicativo de estabilidade desenvolvido demonstrou ser adequado para a determinação da substância ativa na formulação mesmo na presença de produtos de degradação, bem como para a quantificação do fármaco na pele suína e no fluído receptor. Os principais fatores extrínsecos que promovem a degradação do fármaco foram estabelecidos: luz, oxidação e meio básico (este último somente na presença de excipientes). A determinação da cinética de fotodegradação como sendo de primeira ordem demonstra que o processo é dependente da concentração do fármaco, reforçando a necessidade de proteção frente à luz. Já o método por eletroforese capilar mostrou-se não específico frente à formulação placebo simulado, inviabilizando seu uso para o creme. Na avaliação da permeação cutânea das formulações brasileira e americana não foi detectada presença considerável do fármaco no fluído receptor para ambos os produtos. Já na verificação da penetração, não houve diferença significativa na retenção do fármaco na epiderme, entretanto, na derme a diferença foi estatisticamente significativa, com maior concentração retida na análise da formulação americana (α = 0,05). / Objectives: The aim of the present work was to develop, validate and compare stability indicating methods to quantify butenafine hydrochloride (BTF), raw material and commercial cream, as well as to establish the degradation kinetics of the drug in a stress condition. Also, the study had the goal of validating a method to assess and compare the cutaneous permeation/penetration of two different formulations. Methods: A stability-indicating method for the analysis of BTF by high performance liquid chromatography (HPLC) was developed and validated according to the ICH guidelines. The degradation kinetics of the drug (raw material and cream) under the UVC light was determined. Analyzes to develop and validate an analytical method by capillary electrophoresis, to quantify the drug by itself and in the cream, were performed. The chromatographic method previously developed for the semi-solid product was validated to quantify the drug in porcine skin. Then, the cutaneous permeation/penetration of BTF, through the Franz-type cell, was analyzed to compare two different commercial formulations (one of them is Brazilian and the other is American). Results and Conclusions: The developed stability-indicating method was adequate to determine the active substance in the formulation even in the presence of the degradation products, as well as to quantify the drug in porcine skin and in the receptor fluid. The main extrinsic factors that promote the drug degradation were established: light, oxidative and basic media (the last in the presence of the excipient ingredients). The photodegradation kinetics was determined as first order showing that the process is dependent on the drug concentration, reaffirming the necessity of protection against light. The method by capillary electrophoresis was not specific considering the placebo formulation, hindering its use to the cream. During the cutaneous permeation analysis, no drug was found in the receptor media of both the Brazilian and the American formulations. No difference was verified to the epidermis, although to the dermis there was a statistical distinction as the concentration of retained drug from the American formulation was higher (α = 0,05).
104

Remoção da toxicidade do fármaco propranolol e de sua mistura com cloridrato de fluoxetina em solução aquosa empregando irradiação com feixe de elétrons / Removal of toxicity the pharmaceutical propranolol and your mixture with fluoxetine hydrochloride in aqueous solution using radiation with electron beam

BOIANI, NATHALIA F. 10 March 2017 (has links)
Submitted by Maria Eneide de Souza Araujo (mearaujo@ipen.br) on 2017-03-10T16:49:56Z No. of bitstreams: 0 / Made available in DSpace on 2017-03-10T16:49:56Z (GMT). No. of bitstreams: 0 / A saúde do meio ambiente vem sendo comprometida devido ao descarte incorreto de produtos e seus subprodutos. Dentre os contaminantes emergentes encontram-se os fármacos, causadores de problemas ambientais por serem descartados no meio ambiente através dos efluentes. As técnicas convencionais de tratamento são insuficientes na remoção de diversos fármacos, por apresentarem resíduos resistentes e baixa biodegradabilidade. Sendo assim os processos oxidativos avançados vêm sendo estudados como alternativa para o tratamento de diferentes tipos de efluentes. O objetivo desse trabalho foi aplicar o processo de irradiação com feixe de elétrons para reduzir os efeitos tóxicos do propranolol, e de sua mistura com cloridrato de fluoxetina, em solução aquosa. Foram realizados ensaios ecotoxicológicos com o fármaco propranolol, e de sua mistura com o cloridrato de fluoxetina, utilizando como organismos-teste o microcrustáceo Daphnia similis, e a bactéria Vibrio fischeri. Observamos que o organismo D. similis mostrou-se mais sensível as amostras de fármacos quando comparado à bactéria V.fischeri. Após serem submetidas ao tratamento com radiação ionizante, todas as doses aplicadas para o propranolol e a mistura, mostraram significativa redução de toxicidade, tendo como organismo-teste D. similis. Para a bactéria V. fischeri apenas na dose de 5,0 kGy foi verificada a redução da toxicidade para o fármaco propranolol. Quanto à mistura dos fármacos, apenas as doses de 2,5 e 5,0 kGy apresentaram eficiência de remoção da toxicidade. A dose 5,0 kGy mostrou-se a melhor, apresentando redução de 79,94% para D. similis, e 15,64% para V. fischeri, quando expostas ao fármaco propranolol. Quanto à mistura, apresentou 81,59% e 26,93%, para D.similis e V.fischeri, respectivamente. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
105

Análise estereosseletiva do cloridrato de cis-tramadol e de suas impurezas em matéria-prima e formulação farmacêutica / Estereoselective analysis of cis-tramadol hydrocloride and its impurities in raw material and pharmaceutical formulation

Naíssa Prévide Bernardo 10 October 2008 (has links)
O cloridrato de tramadol, analgésico sintético de ação central, possui dois centros quirais: o isômero cis é ativo e o isômero trans é uma impureza de processo. Ambos os enantiômeros do cloridrato de cis-tramadol contribuem para o efeito analgésico, mas através de mecanismos diferentes, complementares e interativos farmacologicamente. Os dois isômeros do cis-tramadol apresentam efeitos terapêuticos, e a presença de impurezas, incluindo os isômeros trans - decorrentes do processo de síntese ou devido à decomposição - podem comprometer a qualidade do produto comercializado. Assim, este trabalho teve como objetivo desenvolver e validar metodologia estereosseletiva para análise do cloridrato de cis-tramadol e das possíveis impurezas quirais ou não na matéria-prima e formulações farmacêuticas. Para a separação e quantificação dos enantiômeros do cloridrato de cis-tramadol e das impurezas trans-tramadol, 1,2-olefina e 1,6-olefina, foi utilizada a coluna Chiralcel® OD-H, fase móvel constituída por hexano (60% e 100% de n-hexano, 1:1, v/v):isopropanol:dietilamina:ácido trifluoracético (99,5:0,5:0,3:0,1, v/v/v/v), na vazão de 0,7 mL min-1 e detecção em 274 nm. A coluna Chiralpak® AD fase móvel constituída por hexano (60% de n-hexano):etanol absoluto:dietilamina (95:5:0,1, v/v/v), na vazão de 1,0 mL min-1 e o comprimento de onda para detecção dos compostos foi de 228 nm foi utilizada para a separação e quantificação das impurezas O-desmetiltramadol, N-desmetiltramadol e tramadol N-óxido. Os métodos desenvolvidos foram devidamente validados através dos parâmetros seletividade, linearidade, precisão, exatidão, intervalo, limite de detecção e limite de quantificação. Os resultados obtidos na validação mostraram que os métodos são adequados para a determinação do cis-tramadol e de suas impurezas na matéria prima e na formulação farmacêutica. / Tramadol hydrochloride is a centrally acting analgesic with two chiral centers; the cis isomer is the active drug and the trans isomer is a process impurity. Both enantiomers of cis-tramadol hydrochloride contribute to the analgesic effect through different, but complementary and interactive pharmacological mechanisms. Although both isomers of cis-tramadol hydrochloride show therapeutic effects, the presence of impurities, originated from the synthesis process or due to degradation, can compromise the quality of the marketed product. The aim of this present work was the development and validation of a stereosselective methodology for the analysis of the drug cis-tramadol hydrochloride and the possible chiral or non-chiral impurities in raw materials and pharmaceutical formulations. The separation and quantitation of cis-tramadol enantiomers and the impurities trans-tramadol, 1,2-olefin and 1,6-olefin were carried out using a Chiralcel® OD-H column, mobile phase of hexane (60% and 100% of n-hexane, 1:1, v/v):2-propanol:diethylamine:trifluoroacetic acid (99,5:0,5:0,3:0,1, v/v/v/v) at a flow rate of 0,7 mL min-1 and detection at 274 nm. For the separation and quantitation of the impurities O-desmethyltramadol, N-desmethyltramadol and tramadol N-oxide, a Chiralpak® AD column was used with a mobile phase of hexane (60% of n-hexane):ethanol absolute: diethylamine (95:5:0,1, v/v/v) at a flow rate of 1,0 mL min-1 and detection at 228 nm. The methods were validated using the parameters selectivity, linearity, precision, accuracy, range, detection limit and quantitation limit. The results obtained show that the methods are suitable for the analysis of cis-tramadol and its impurities in raw material and pharmaceutical formulation.
106

Standaarde vir 'n holisties interaktiewe bestuursbenadering vir die praktyk van diagnosering van kinders met aandagtekort hiperaktiwiteitsversteuring en hul terapie met Ritalin

Van Zyl, Jacques 16 August 2012 (has links)
D.Ed. / The practice regarding the diagnosing and therapeuterising, with Ritalin, of children with ADHD (Attention Deficit Hyperactivity Disorder) is inadequate. There is in general practice little, if any, signs of holistic interactive co-operation amongst practitioners regarding diagnosing and therapeuterising, with Ritalin, exceptions excluded. The practice situation reflects a rather fragmented image, unscientific practises regarding diagnostic and therapeutic instruments and procedures, ignorance and incompleteness. The rational why this study was undertaken is because of the researcher's experience of the overwhelming inadequacy of this practice. The aim of this research was to develop, validate and describe standards for the holistic interactive management of the practice of diagnosing of the child \Vith ADHD and his/her therapy, with Ritalin. These standards can contribute towards improvement of the total practice, that is improvement of aid rendering to this child in order to optimise his/her functioning accordingly. In order to reach this aim, a research method was followed whereby an intensive literature study, multiple case studies and a questionnaire survey regarding a variety of professional practitioners and parents, was introduced in order to obtain data from the practice situation. Data was continuously qualitatively analised within the parameters of a theoretically grounded conceptual framework. These analyses eventually culminated in the description of concept standards and revised concept standards which were submitted to five domain experts for validation. The final standards which were determined through a process of a reasonable high level of consensus amongst these experts, is described in two official languages, namely Afrikaans and English. The final standards reflect the need from practice, namely holistic interactive management of the procedures of diagnosis and therapy, with Ritalin, of the child with ADHD.
107

Uticaj apigenina i natrijum-deoksiholata na biološku raspoloživost raloksifena / Influence of apigenin and sodium deoxycholate on biological availability of raloxifene

Gigov Slobodan 05 July 2017 (has links)
<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>
108

Hydrogely na bázi kladně nabitých poylelektrolytů / Hydrogels based on cationic polyelectrolytes

Jarábková, Sabína January 2016 (has links)
This diploma thesis deals with the study of physical hydrogels based on positively-charged polyelectrolyte. The study is to investigate the interaction of selected positively-charged polyelectrolytes with oppositely charged surfactants in water and in physiologicla saline solution (0.15 M NaCl). The influence of the process for preparing hydrogels. Hydrogels were prepared by dry or wet. Were tested solubilization abilities hydrogels prepared using the hydrophobic dye oil red O were also measured rheological properties of the hydrogels prepared using frequency oscillatory tests and flow tests, depending on the concentration of the polymer or surfactant. For the rheological experiments suggest that chitosan is capable of forming rigid hydrogels with better mechanical properties than the dextran in the presence of both surfactants. Selected samples were also carried out experiments using fluorescent sold prodan, nile red and -naphthol as fluorescent probes. And in selected experiments was determined by solids content in percentage depending on the concentration used polyelectrolytes or surfactants.
109

Photodegradation of selected pharmaceuticals using magnetic-carbon dot loaded on different TiO2 nanostructures.

Moshoeu, Edna Dimakatso 11 1900 (has links)
M.Tech. (Department of Chemistry, Faculty of Applied and Computer Sciences), Vaal University of Technology. / To replace the conventional wastewater treatment technology, photocatalysis has the best potential due to its utilization of visible light to photodegrade organic and inorganic contaminants. However, agglomeration of nanoparticles leads to serious decrease in photocatalytic performance when applied in slurry form, due to hindrance effect. TiO2 semiconductor photocatalyst mediated advanced oxidation process is referred to as one of the most efficient technologies to degrade organic pollutants in water. However, TiO2 semiconductor for water purification hinders large scale applicability due to poor activity under visible light and the recombination of photogenerated electron and hole pairs. The modification of TiO2 semiconductor photocatalyst with carbon dots (CDs) is of high importance due to low toxicity, aqueous stability, enhanced surface area, economic feasibility, good biocompatibility and chemical inertness of CDs. Herein, strategies are highlighted to improve the activity of TiO2 semiconductor photocatalyst by coupling it with CDs and Fe2O3. In this study, we study the morphological influence of TiO2 nanostructures on photocatalytic degradation of tetracycline hydrochloride present in industrial wastewater. TiO2 nanostructures, nanotubes, nanospheres and nanofibers were Synthesized using the hydrothermal technique. TiO2 nanotubes, nanofibers and nanospheres were prepared by the hydrothermal treatment of TiO2 nanoparticles with different NaOH concentrations (5, 10 and 12 N) at 120 and 140 ˚C; afterwards, HCl was added until it reached pH 2. Both the crystalline phase and coordination of the TiO2 nanotubes, nanofibers and nanospheres were composed principally. Likewise, the surface area, pore volume and pore size of the TiO2 nanotubes, nanofibers and nanospheres changed with the NaOH rinsing treatment. The photocatalytic activity for tetracycline degradation were strongly enhanced by the nanofibers and nanotubes in the basic and acid media, respectively, showing a relationship between their structure and the medium. TiO2 nanostructures and the composite material were characterized by scanning electron microscope\SEM), X-Ray Diffraction (XRD), transmission electron microscope (TEM) and Fourier transform infrared (FTIR). BET surface area analysis was carried out using nitrogen adsorption desorption curves. The results show that TiO2 morphology had great influence on photocatalytic degradation of tetracycline hydrochloride due to difference in specific surface area and pore volume of nanostructures. The photocatalytic degradation experiments were carried out for three hours under visible-LED light. TiO2 nanofibers show better degradation performance than nanotubes and nanospheres due to presence of large surface area for reaction, higher porosity with dispersion of active sites at different length scales of pores and presence of oxygen vacancies. Agricultural biomass pine bark serves as a carbon source and was doped into TiO2-nanofibers (TNF) to fabricate the composite material (CD-TNF). CD-TNF composite nanofibers were prepared via a facile hydrothermal method. This study revealed that the photocatalytic efficiency of tetracycline (TC) under visible light irradiation of the composite nanofiber is higher than that of pure TiO2-nanofiber. The anchored CDs can both enhance the light absorption and suppress photogenerated electron hole recombination which results in the enhancement of catalytic and antibacterial properties. The CDs can better capture and transfer photogenerated electrons through the Ti-O-C and Fe-O-C bonds. Moreover, CDs can improve the utilization of photogenerated electrons and the electrons in CDs are captured by O2 to produce O2•- radicals and the role of O2•- radicals in the photocatalytic process is significantly improved. A new efficient photocatalyst consisting of TiO2/CD/Fe2O3 composite material was Synthesized by the hydrothermal treatment and applied in the photodegradation of 5 mg/L tetracycline hydrochloride (TC) under visible-LED light. The CDs/TiO2/Fe2O3 composite showed enhanced photocatalytic performance for tetracycline photodegradation when compared with TiO2/CDs and pure TiO2 under the visible light irradiation. The mechanism of the improved photocatalytic activity over CDs/TiO2/Fe2O3 was also investigated. The influence of the interface formation between Fe2O3 and TiO2/CDs affects severely the charges separation efficiency and enhances the electron transfer to keep on the existence of Fe3+/Fe2+ moieties that take significant role in the reaction mechanism.
110

Stanovení přítomnosti inhibitorů fosfodiesterázy v komunálních odpadních vodách / Determination of the presence of phosphodiesterase inhibitors in municipal wastewater

Smutná, Michaela January 2014 (has links)
This diploma thesis is focused on the determination of phosphodiesterase 5 selective inhibitors in communal waste waters. In this study phosphodiesterase inhibitors levels in municipal waste waters from sewage treatment plants with different numbers of equivalent inhabitants were analyzed. Namely it was sewage treatment plants in Brno – Modřice, Luhačovice and Hodonín. In each of the above mentioned facilities 24 - hour cumulated samples of the influent and effluent waste water were collected. On the Brno - Modřice sewage treatment plant also weekly monitoring of the concentration of phosphodiesterase inhibitors was realized.

Page generated in 0.0613 seconds