• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 19
  • 10
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 35
  • 10
  • 8
  • 6
  • 6
  • 6
  • 6
  • 6
  • 6
  • 6
  • 6
  • 5
  • 4
  • 4
  • 4
  • 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.
21

Antihistamininių vaistų (klemastino fumarato, loratadino, desloratadino) mišinio išskyrimas iš kraujo plazmos ir identifikavimas efektyviosios skysčių chromatografijos metodu / Antihistamines (clemastine fumarate, loratadine, desloratadine) extraction from human plasma and identification using high performance liquid chromatography

Zdanytė, Birutė 30 June 2014 (has links)
Darbo tikslas: optimizuoti metodiką, kuria būtų galima atlikti antihistamininių vaistų mišinio, sudaryto iš klemastino fumarato, loratadino ir desloratadino, ekstrakciją iš kraujo plazmos ir kokybinį nustatymą efektyviosios skysčių chromatografijos metodu. Darbo uždaviniai: Atlikti mokslinės literatūros analizę siekiant įvertinti antihistamininių vaistų savybes ir pasirinktų junginių ekstrakcijos iš kraujo plazmos ir tapatybės nusatymo metodikas. Optimizuoti ir validuoti ESC metodiką kokybiniam pasirinktų preparatų mišinio nustatymui iš kraujo plazmos. Parinkti klemastino fumarato, loratadino ir desloratadino skysčių – skysčių ekstrakcijos iš kraujo plazmos sąlygas. Apibendrinti gautus ekstrakcijos ir ESC rezultatus. Metodai: skysčių – skysčių ekstrakcija ir ESC. Tyrimo objektas: kraujo plazma, į kurią įterpti antihistamininiai vaistai klemastino fumaratas, loratadinas, desloratadinas ir jų mišinys. Rezultatai: tiriamųjų medžiagų sulaikymo laikai: desloratatadino apie – 5,9 min, loratadino – apie 11,4 min, klemastino fumarato – apie 13,2 min. Validuota ESC atlikimo metodika. Atliekant ekstrakciją su trichlormetanu neišsiekstrahavo nei vienas tiriamasis junginys, su dichlormetanu – loratadinas, su dietileteriu ir cikloheksanu – visi trys tiriamieji junginiai. Išvados: 1. Atlikta mokslinės literatūros analizė, apžvelgiant antihistamininių vaistų savybes, ekstrakcijos iš kraujo plazmos būdus bei identifikavimo metodus, didžiausią dėmesį skiriant efektyviajai skysčių... [toliau žr. visą tekstą] / Aim: to optimise a method, by which mixture of antihistamines containing clemastine fumarate, loratadine and desloratadine could be extracted from human plasma and qualitative determination using high performance liquid chromatogrophy could be made. Tasks: to carry out analysis of scientific literature and evaluate characteristics of antihistamines and methods of chosen compounds extraction from human plasma and identity determination. Optimise and validate HPLC method for qualitative determination of chosen medicines. Select conditions suitable for chosen antihistamines liquid – liquid extraction from human plasma. Carry out qualitative determination of clemastine fumarate, loratadine and desloratadine in human plasma using validated HPLC method. Summarize results of extraction and HPLC. Methods: liquid – liquid extraction and HPLC. Object: human plasma with embedded antihistamines: clemastine fumarate, loratadine, deloratadine and their mixture. Results: retention times of test substances: desloratadine – 5,9 min, loratadine – 11,4 min, clemastine fumarate – 13,2 min. HPLC method was validated. None of the compounds were extracted using trichlormethan. Only loratadine was extracted using dichlormethan. All three compounds were extracted using diethyl ether and cyclohexane. Conclusions: 1. Analysis of scientific literature was caried out, characteristics of antihistamines, methods of extraction from human plasma and identity determination of chosen compounds were overviewed... [to full text]
22

The Attempted Synthesis of some Heterocyclic Sulfones

Compton, William David 08 1900 (has links)
This thesis describes two experiments: one related to antihistamines, and the other related to antitubercular compounds.
23

Complex cognitive performance and antihistamine use

Rice, Valerie J. Berg 05 February 2007 (has links)
Research has demonstrated that the majority of antihistamines (H1 antagonists) have sedative effects and can impair psychomotor performance; however, it is claimed that astemizole (hismanal) does not possess central nervous system side effects. A two-factor, repeated measures, double-blind design was used to compare the effects of three treatments (two antihistamines and one placebo) on cognitive information processing, mood, selected physiological measures, subjective feelings of drowsiness, and subjective performance ratings in 28 healthy men. Evaluations were given at 1,3,5,7,9,11,13, and 15 hours post ingestion. Time-of-day effects were evident in following directions, unstable tracking, code substitution, serial addition/subtraction, logical reasoning, manikin, and pattern comparison tasks. A general trend of improved scores through the day was observed and a temporal pattern of a low performance was suggested in the afternoon (2:00 pm and 4:00 pm). Temporal effects were noted for physiological measures. Benadryl produced performance decrements at one hour post ingestion on the following directions task, at one and a half hours on the unstable tracking task, and at three hours on the serial addition/subtraction task. No decrements in performance were found post ingestion of hismanal and, in fact, the hismanal group performed the serial addition/subtraction task more quickly than either the placebo or benadryl groups at five hours post ingestion. At three and a half hours post ingestion, the performance of the benadryl group remained poorer than the hismanal group on unstable tracking, but was not different from the placebo group. A higher level of tension, greater fatigue, and lower level of activity was experienced post benadryl. Lower vigor-activity and higher confusion-bewilderment post hismanal and benadryl were noted one hour post ingestion; however, confusion was lower and activity was higher for hismanal than benadryl. Low vigor-activity, high confusion, increased sleepiness, and low perceived performance post benadryl persisted for three hours, while fatigue-inertia persisted for seven hours. Subjects were able to determine receipt of a placebo versus an antihistamine following ingestion of either a placebo or benadryl. Results suggest that hismanal is superior to benadryl for avoidance of subjective effects and performance of information processing tasks. / Ph. D.
24

Evaluation of antihistamines for in vitro antimalarial activity against Plasmodium falciparum

Aneesa, Shaik January 2010 (has links)
Magister Pharmaceuticae - MPharm / The declining efficacy of antimalarial drugs against resistant Plasmodium falciparum strains in several endemic regions has amplified the world’s burden of neglected diseases. This has highlighted the need for alternate strategies for chemotherapy and chemoprophylaxis. Since malaria is prevalent primarily in third world countries, it is critical for novel therapies to be affordable. Previous research has found that some antihistamines possess inherent antimalarial activity and cause a marked reversal of chloroquine resistance in vitro and in vivo. Promising results have been demonstrated when chlorpheniramine was combined with chloroquine to reverse chloroquine resistance in two African studies (Sowunmi et al, 1997; Abok., 1997).Recently, astemizole and its principle human metabolite desmethylastemizole were identified as potent inhibitors of Plasmodium falciparum at sub-micromolar concentrations in both chloroquine sensitive and chloroquine resistant parasites, showing efficacy in vitro and in two mouse models. The promising results observed with these studies warrant a more comprehensive understanding of how antihistamines interact with the malaria parasite. Additionally, analysing the different structural and mechanistic characteristics of antihistamines may lead to the design and development of effective and affordable antimalarial agents or chloroquine resistance modulators.This thesis describes the antimalarial activity of mainly off-patent (generic) antihistamines by comparing the efficacy of a total of 24 antihistamines, representing histamine1, histamine2, and histamine3 receptor antagonists, against chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum. Cyproheptadine, ketotifen, loratadine, desloratadine, 3-(1HImidazol-4-yl) propyldi (p-fluorophenyl) methyl ether hydrochloride and ciproxifan display IC50 values less than 4μg/ml. There was no significant difference in the sensitivity to antihistamines among the chloroquine sensitive and resistant parasites tested. A tricyclic nucleus appears to be an important structural scaffold for antihistamines which exhibit low IC50 values. Synergistic studies indicate that enhancement of the antimalarial effect of chloroquine on P.falciparum was observed with the ethanolamines against the chloroquine sensitive parasites.Cyproheptadine, ketotifen and desloratadine exerted a marked synergistic action with chloroquine against chloroquine sensitive and resistant parasites. Chlorpheniramine exhibited synergism with chloroquine against resistant parasites only.Microscopic studies illustrate the effect of antihistamines on parasite morphology when compared to control. Using immunofluorescence microscopy, it was seen that ketotifen decreases haemoglobin localization while cyproheptadine increases haemoglobin localization in the parasite’s food vacuole. Western blots have confirmed these results, in addition to indicating that chlorpheniramine decreases the haemoglobin content in the parasite. The results confirm that certain antihistamines do indeed cause a reduction in the growth of malaria parasites. Furthermore, the histamine1 and histamine3 receptor antagonists are most active while histamine2 receptor antagonists have no antimalarial activity. Microscopic studies suggest that antihistamines do not exert their antimalarial effect via a single mechanism of action.I wish to express my sincere appreciation to the following people and institutions whose supervision and assistance made the presentation of this thesis possible:My supervisor, Prof. Henry Leng. Thank for always believing in me. Your encouragement, kindness and calm temperament has given me the strength to complete this thesis even when times were tough. Your wisdom and understanding will always be remembered.My co-supervisor, Prof. Pete Smith. I sincerely thank you for allowing me the opportunity to work in your laboratory and for welcoming me into the department. Your kindness and welcoming attitude will forever be appreciated. Thank you for always being patient and understanding.Dr. Uschi Wiehart. Thank you for all the help in the laboratory and always being there for me. I truly value and appreciate your contribution to this thesis. Your friendship has added so much positive energy to my life. Thank you for your wisdom, inspirational advice and unfaltering encouragement Sumaya and Ntokosi, your help, advice and company in tissue culture, are truly appreciated.The UCT, Pharmacology students. Thank for all your assistance.My dearest Pharmaceutical Chemistry colleagues, Jaques Joubert, for your friendship and support and for always listening and Prof. Peter Eagles, your kindness, support and wise advice has given me strength when I needed it most. To my other School of Pharmacy colleagues. Prof. Sarel Malan and team, for your support and motivation.To my family for all your support and wisdom and to my baby brothers; Omar and Uzair for all the joy that you bring to my life.And finally to my dearest husband, Zaheer for all your love and support throughout my studies and for taking me to UCT to culture parasites every weekend
25

Effects of Spantide on Guinea Pig Coronary Resistance Vessels

Hoover, Donald B. 01 January 1991 (has links)
Effects of spantide ([D-Arg1,D-Trp7,9,Leu11]substance P) on coronary resistance vessels were studied in isolated guinea pig hearts perfused at constant rate with isotonic buffer containing 20 or 40 mM KCl. Spantide (1 μM) caused a 20-fold rightward shift of the substance P (SP) dose-response curve for vasodilation with no change in maximum (KB=5.3×10-8 M). Bolus injections of 0.25 to 250 pmol spantide had no effect, but higher doses caused a brief vasodilation followed by a larger, more prolonged vasoconstriction. Histamine produced similar changes in perfusion pressure. Antihistamines (H1 and H2) reduced or blocked responses to spantide and histamine. These findings indicate spantide is a competitive antagonist to SP in guinea pig coronary resistance vessels. In addition, high doses of spantide can cause prominent vascular effects which are mediated by histamine.
26

Planejamento e sintese de compostos potencialmente ligantes dos receptores 5-HT2C e H4 / Design and synthesis of compounds potentially ligands of 5-HT2C e H4

Fernandes, João Paulo dos Santos 30 November 2012 (has links)
A serotonina e a histamina são duas das mais importantes aminas biogênicas do organismo. Regulam série de funções fisiológicas, como fluxo sanguíneo, temperatura corpórea, sono, fome, liberação de hormônios, comportamento afetivo e humor, entre outras. Assim, há grande interesse no planejamento e desenvolvimento de fármacos que interferem na transmissão serotoninérgica e histaminérgica, para futura aplicação como antidepressivos, antipsicóticos, ansiolíticos e anorexígenos, além de perifericamente, apresentarem possíveis ações antiinflamatórias. O objetivo deste trabalho é apresentar a síntese de compostos contendo os núcleos pirrolquinolínico, benzoindólico e benzodiidrofurânico com potencial atividade ligante nos receptores 5-HT2C e H4, assim como avaliar a seletividade desses compostos em comparação aos receptores 5-HT2A/B e H3. Sintetizou-se série de compostos utilizando reações de alilação, adição à carbonila, termociclização, rearranjo de Claisen, iodociclização e substituição nucleofílica para a obtenção dos compostos finais. Estudos de otimização de síntese por metodologia de superfície de resposta também são apresentados, assim como estudos de relações quantitativas entre estrutura química e atividade biológica de compostos ligantes dos receptores 5-HT2C e H4. / Serotonin and histamine are two major biogenic amines in the body. They regulate several physiological functions such as blood flow, body temperature, sleep, hunger, hormone release, emotional behavior and mood, among others. Thus, there is great interest in the design and development of drugs that interfere with serotoninergic and histaminergic transmission, for future use as antidepressants, antipsychotics, anxiolytics and anorectic, and peripherally, possible anti-inflammatory actions. The aim of this work is to present the synthesis of compounds containing the pyrroloquinoline, benzoindole and benzodihydrofurane nucleus with potential binding activity to 5-HT2C and H4 receptors, as well as to evaluate the selectivity of these compounds in comparison to 5-HT2A/B and H3. Series of compounds were synthesized using allylation, carbonyl addition, thermal cyclization, Claisen rearrangement, iodocyclization and nucleophilic substitution reactions. Optimization studies for the synthesis using response surface methodology are also presented, as well as quantitative structure-activity relationships studies of ligands of 5-HT2C and H4 receptors.
27

Desenvolvimento de métodos analíticos por cromatografia líquida de alta eficiência e eletroforese capilar para medicamentos anti-histamínicos / Development of analytical methods by high performance liquid chromatography and capillary electrophoresis for antihistamines drugs.

Mothé, Cintia Maria Alves 02 October 2013 (has links)
Loratadina, desloratadina, rupatadina e ebastina são anti-histamínicos H1 de segunda geração, pertencentes ao grupo piperidínico, utilizados em casos clínicos de afecções alérgicas devido a sua ação sobre a histamina, que é o principal mediador da alergia e, também, pela sua ação anti-inflamatória ocorrida pelo bloqueio do fator de ativação plaquetária (PAF). Esses fármacos são denominados agonistas inversos dos receptores H1 não-sedativos. No presente estudo, foram desenvolvidos e validados métodos para a quantificação de loratadina, desloratadina, rupatadina e da ebastina em produtos farmacêuticos utilizando as técnicas de cromatografia líquida de alta eficiência (CLAE) e eletroforese capilar (CE). As análises por CLAE foram realizadas utilizando coluna LiChroCART® 100 RP- CN, 5 µm, (125 x 4 mm), fase móvel constituída MEOH:Tampão Fosfato de Sódio 20 mmol/L pH 3,0, (65:35 v/v), vazão de 1,0 mL/min; volume de injeção 20 µL, temperatura de 25°C ± 1ºC, detecção CLAE-UV λmáx: 254 nm. Paralelamente, foram desenvolvidos e validados métodos por CE, utilizando modo de separação por CZE com capilar de sílica fundida de 40,5 cm efetivos e 50 cm totais, 75 µm de diâmetro interno e 375 µm de diâmetro externo, eletrólito: ácido bórico 35 mmol/L, pH 2,5, tensão aplicada de 20 kV para, loratadina, desloratadina e rupatadina, e de 24 kV para ebastina, injeção hidrodinâmica de 0,5 psi por 3 segundos, temperatura de 25ºC ± 1ºC. Detecção CE-UV λmáx:205 nm. Os procedimentos foram validados, avaliando-se os parâmetros de especificidade, linearidade, precisão, exatidão, limite de detecção e quantificação e robustez, cujos resultados cumpriram os requisitos preconizados pela RE nº 899 da ANVISA. Os métodos propostos foram aplicados na análise de produtos farmacêuticos. Deste modo, os procedimentos estabelecidos podem ser aplicados para o aprimoramento do controle de qualidade de medicamentos, bem como garantir a segurança e a eficácia do uso terapêutico. / Loratadine, desloratadine, rupatadine and ebastine are second generation H1 antihistamines belonging to the group piperidine. They are often used in the clinical cases of allergic diseases due to their action on histamine, which is the main mediator of allergy and also by their anti-inflammatory action mediated through platelet activating factor (PAF) blocking activity. These drugs are called inverse agonists of non-sedating H1 receptor. In present study a high performance liquid chromatographic (HPLC) and capillary electrophoresis (CE) methods were developed and validated for quantitative determination of loratadine, desloratadine, ebastine rupatadine in pharmaceutical drug products. The HPLC method was developed using LiChroCART ® RP-100 CN 5 microns (125 x 4 mm) column, mobile phase composed of MeOH: sodium phosphate buffer 20 mmol/L, pH 3.0 (65:35 v/v ) at a flow rate 1.0 mL/min, injection volume 20µL. The temperature was maintained at 25 ± 1 °C and UV detection was made at 254 nm. In parallel, a CE method was developed and validated using CZE mode using a fused silica capillary of 40.5 cm effective length and 50 cm total length with inner and outer diameter of 75 µm and 375µm, respectively. The background electrolyte was composed of 35 mmol/L boric acid, pH 2.5, applied voltage of 20 kV for loratadine, desloratadine and rupatadine and 24 kV for ebastine, hydrodynamic injection at 0.5 psi for 3 seconds. All analyses were made at 25 ± 1 °C and UV detection was made at 205 nm. The CE method was validated and following parameters were evaluated; specificity, linearity, precision, accuracy, limit of detection and quantification and robustness. The results met the requirements recommended by RE No. 899 of ANVISA. The proposed methods were applied in the analysis of referred pharmaceuticals. Thus, the proposed methods can be applied to improve the quality control of pharmaceuticals and consequently ensure the safety and efficacy of these products in therapeutic use.
28

Desenvolvimento de métodos analíticos por cromatografia líquida de alta eficiência e eletroforese capilar para medicamentos anti-histamínicos / Development of analytical methods by high performance liquid chromatography and capillary electrophoresis for antihistamines drugs.

Cintia Maria Alves Mothé 02 October 2013 (has links)
Loratadina, desloratadina, rupatadina e ebastina são anti-histamínicos H1 de segunda geração, pertencentes ao grupo piperidínico, utilizados em casos clínicos de afecções alérgicas devido a sua ação sobre a histamina, que é o principal mediador da alergia e, também, pela sua ação anti-inflamatória ocorrida pelo bloqueio do fator de ativação plaquetária (PAF). Esses fármacos são denominados agonistas inversos dos receptores H1 não-sedativos. No presente estudo, foram desenvolvidos e validados métodos para a quantificação de loratadina, desloratadina, rupatadina e da ebastina em produtos farmacêuticos utilizando as técnicas de cromatografia líquida de alta eficiência (CLAE) e eletroforese capilar (CE). As análises por CLAE foram realizadas utilizando coluna LiChroCART® 100 RP- CN, 5 µm, (125 x 4 mm), fase móvel constituída MEOH:Tampão Fosfato de Sódio 20 mmol/L pH 3,0, (65:35 v/v), vazão de 1,0 mL/min; volume de injeção 20 µL, temperatura de 25°C ± 1ºC, detecção CLAE-UV λmáx: 254 nm. Paralelamente, foram desenvolvidos e validados métodos por CE, utilizando modo de separação por CZE com capilar de sílica fundida de 40,5 cm efetivos e 50 cm totais, 75 µm de diâmetro interno e 375 µm de diâmetro externo, eletrólito: ácido bórico 35 mmol/L, pH 2,5, tensão aplicada de 20 kV para, loratadina, desloratadina e rupatadina, e de 24 kV para ebastina, injeção hidrodinâmica de 0,5 psi por 3 segundos, temperatura de 25ºC ± 1ºC. Detecção CE-UV λmáx:205 nm. Os procedimentos foram validados, avaliando-se os parâmetros de especificidade, linearidade, precisão, exatidão, limite de detecção e quantificação e robustez, cujos resultados cumpriram os requisitos preconizados pela RE nº 899 da ANVISA. Os métodos propostos foram aplicados na análise de produtos farmacêuticos. Deste modo, os procedimentos estabelecidos podem ser aplicados para o aprimoramento do controle de qualidade de medicamentos, bem como garantir a segurança e a eficácia do uso terapêutico. / Loratadine, desloratadine, rupatadine and ebastine are second generation H1 antihistamines belonging to the group piperidine. They are often used in the clinical cases of allergic diseases due to their action on histamine, which is the main mediator of allergy and also by their anti-inflammatory action mediated through platelet activating factor (PAF) blocking activity. These drugs are called inverse agonists of non-sedating H1 receptor. In present study a high performance liquid chromatographic (HPLC) and capillary electrophoresis (CE) methods were developed and validated for quantitative determination of loratadine, desloratadine, ebastine rupatadine in pharmaceutical drug products. The HPLC method was developed using LiChroCART ® RP-100 CN 5 microns (125 x 4 mm) column, mobile phase composed of MeOH: sodium phosphate buffer 20 mmol/L, pH 3.0 (65:35 v/v ) at a flow rate 1.0 mL/min, injection volume 20µL. The temperature was maintained at 25 ± 1 °C and UV detection was made at 254 nm. In parallel, a CE method was developed and validated using CZE mode using a fused silica capillary of 40.5 cm effective length and 50 cm total length with inner and outer diameter of 75 µm and 375µm, respectively. The background electrolyte was composed of 35 mmol/L boric acid, pH 2.5, applied voltage of 20 kV for loratadine, desloratadine and rupatadine and 24 kV for ebastine, hydrodynamic injection at 0.5 psi for 3 seconds. All analyses were made at 25 ± 1 °C and UV detection was made at 205 nm. The CE method was validated and following parameters were evaluated; specificity, linearity, precision, accuracy, limit of detection and quantification and robustness. The results met the requirements recommended by RE No. 899 of ANVISA. The proposed methods were applied in the analysis of referred pharmaceuticals. Thus, the proposed methods can be applied to improve the quality control of pharmaceuticals and consequently ensure the safety and efficacy of these products in therapeutic use.
29

Planejamento e sintese de compostos potencialmente ligantes dos receptores 5-HT2C e H4 / Design and synthesis of compounds potentially ligands of 5-HT2C e H4

João Paulo dos Santos Fernandes 30 November 2012 (has links)
A serotonina e a histamina são duas das mais importantes aminas biogênicas do organismo. Regulam série de funções fisiológicas, como fluxo sanguíneo, temperatura corpórea, sono, fome, liberação de hormônios, comportamento afetivo e humor, entre outras. Assim, há grande interesse no planejamento e desenvolvimento de fármacos que interferem na transmissão serotoninérgica e histaminérgica, para futura aplicação como antidepressivos, antipsicóticos, ansiolíticos e anorexígenos, além de perifericamente, apresentarem possíveis ações antiinflamatórias. O objetivo deste trabalho é apresentar a síntese de compostos contendo os núcleos pirrolquinolínico, benzoindólico e benzodiidrofurânico com potencial atividade ligante nos receptores 5-HT2C e H4, assim como avaliar a seletividade desses compostos em comparação aos receptores 5-HT2A/B e H3. Sintetizou-se série de compostos utilizando reações de alilação, adição à carbonila, termociclização, rearranjo de Claisen, iodociclização e substituição nucleofílica para a obtenção dos compostos finais. Estudos de otimização de síntese por metodologia de superfície de resposta também são apresentados, assim como estudos de relações quantitativas entre estrutura química e atividade biológica de compostos ligantes dos receptores 5-HT2C e H4. / Serotonin and histamine are two major biogenic amines in the body. They regulate several physiological functions such as blood flow, body temperature, sleep, hunger, hormone release, emotional behavior and mood, among others. Thus, there is great interest in the design and development of drugs that interfere with serotoninergic and histaminergic transmission, for future use as antidepressants, antipsychotics, anxiolytics and anorectic, and peripherally, possible anti-inflammatory actions. The aim of this work is to present the synthesis of compounds containing the pyrroloquinoline, benzoindole and benzodihydrofurane nucleus with potential binding activity to 5-HT2C and H4 receptors, as well as to evaluate the selectivity of these compounds in comparison to 5-HT2A/B and H3. Series of compounds were synthesized using allylation, carbonyl addition, thermal cyclization, Claisen rearrangement, iodocyclization and nucleophilic substitution reactions. Optimization studies for the synthesis using response surface methodology are also presented, as well as quantitative structure-activity relationships studies of ligands of 5-HT2C and H4 receptors.
30

Estudo farmacognóstico comparativo de Passiflora alata Curtis e Passiflora nítida Kunth (Passifloraceae). Avaliação das atividades antiúlcera e antioxidante dos seus extratos / Comparative pharmacognostic study of Passiflora alata Curtis and P. nitida Kunth (Passifloraceae). Evaluation of antiulcer and antioxidant activities of its extracts

Wasicky, André 15 October 2007 (has links)
Passiflora alata Curtis e P. nitida Kunth, espécies brasileiras, foram submetidas ao estudo farmacognóstico comparativo. P. alata tem sido utilizada há tempos na medicina tradicional e em preparações farmacêuticas. No estudo farmacobotânico, as folhas das duas espécies apresentaram semelhança na forma, no tamanho e na ausência de indumento. Diferem quanto ao número de glândulas peciolares. P. alata apresenta geralmente dois pares de glândulas e P. nitida, um par. Anatomicamente, as duas espécies mostraram características comuns ao gênero Passiflora: mesofilo dorsiventral; drusas no mesofilo, na nervura mediana, na região cortical, medular e floemática do caule; feixes vasculares colaterais. Embora as duas espécies apresentem nervura mediana biconvexa, a de P. alata evidencia as carenas pronunciadamente salientes, principalmente na face abaxial. Outro aspecto diferencial observa-se na forma do caule: em P. alata é quadrangular e, em P. nitida, arredondada. A seqüência de tecidos assemelha-se, com exceção do maior desenvolvimento de colênquima nas arestas de P. alata. A triagem fitoquímica evidenciou a presença de flavonóides nas duas espécies e a ausência de alcalóides em ambas, tanto na droga vegetal quanto nos extratos. Formação de espuma persistente foi observada com a droga vegetal preparada com P. alata. A hemólise foi observada com a droga e o extrato desta espécie. Os flavonóides foram quantificados como 0,42% ± 0,01 em P. alata e 0,10% ± 0,01 em P. nitida. No ensaio da atividade antioxidante, a EC50 de P. alata foi de 1061,2 ± 8,5 µg/mL e a de nitida 128,0 ± 0,9 µg/mL, no ensaio do DPPH, e de 1076 ± 85 µµmol de Trolox/g de extrato e de 1985 ± 104 µmol de Trolox/g de extrato no ensaio de ORAC, respectivamente. No ensaio de atividade antiúlcera aguda P. alata exibiu, na área total de lesão (ATL), proteção contra as lesões gástricas de 100%, P. nitida de 84% e lansoprazol, o controle positivo, de 76%. Quanto à área relativa de lesão (ARL), alata exibiu proteção contra as lesões de 99,45%; P. nitida, de 82,27% lansoprazol, de 81,44%, no ensaio de lesão gástrica induzida por etanol/HCI com 300 mmol/L de HCI e extratos na dose de 400 mg/kg. As doses de 100,200 e 400 mg/kg dos extratos foram testadas nas mesmas condições com 150 mmol/L de HCI. P. alata apresentou, na ATL, 100% de proteção contra as lesões gástricas nas três concentrações e lansoprazol, de 75%. Na ARL, P. alata exibiu 100% de proteção lansoprazol, de 76,92%. P. nitida apresentou, na ATL, proteção contra as lesões gástricas de 25%, 74% e 94% nas três concentrações, respectivamente e, lansoprazol, de 80%. Na ARL, P. nitida exibiu 27,40%, 74,00% e 91,78% de proteção, respectivamente e lansoprazol, de 78,08%. Baseando-se neste estudo possível distinguir as duas espécies através de características morfoanatômicas das folhas e dos caules e, através do perfil cromatográfico. Ambas as espécies apresentaram atividade antiúlcera promissora. / Passiflora alata Curtis and P. nitida Kunth, Brazilian species, were selected for the comparative pharmacognostic study. P. alata has been used for a long time folk medicine and pharmaceutical preparations. In the pharmacobotanic study, leaves from both species showed similarities in shape, size and in the absence indumenta. They differ by the number of petiolar glands. P. alata presents generally two pairs of glands and P. nitida, one pair. Anatomically, both species showed common characteristics to the Passiflora genera: dorsiventral mesophyll; druses the mesophyll, midrib, cortex, medulla and phloem; collateral vascular bundles. Both species\' midrib presented a biconvex shape, but P. alata\'s was prominently shaped, notably in the abaxial surface. Another differential aspect was observed the stem shape: P. alata was quadrangular and P. nitida was rounded. The tissues sequence presented similarity, with exception to larger collenchyma development in P. alata\'s edges. The phytochemical screening showed presence of flavonoids and absence of alkaloids in both species, in the crude drug and extracts. Formation persistent foam was observed with the crude drug of P. alata. Hemolisis was observed with the crude drug and extract of this species. Flavonoids were quantified as 0.42% ± 0.01 in P. alata and 0.10% ± 0.01 in P. nitida. In the antioxidant activity assay, the EC50 of P. alata was 1061.2 ± 8.5 µg/mL and of P. nitida , 128.0 ± 0.9 µg/mL, in the DPPH assay, and 1076 ± 85 µmol Trolox/g extract and 1985 ± 104 µmol Trolox/g extract in the ORAC assay, respectively. In the antiulcer activity assay P. alata showed, in total lesion area (TLA), protection against gastric lesions 100%, P. nitida 84% and lansoprazole, the positive control, 76%. In relative lesion area (RLA), P. alata showed protection against lesions of 99.45%, P. nitida82.27% and lansoprazole 81.44%, in the HCl/ethanol-induced gastric lesion assay, with HCI 300 mmol/L and extracts at doses of 400 mg/kg. Doses of 100, 200 e 400 mg/kg extracts were tested in the same conditions with HCl 150 mmol/L. P. alata showed, TLA, protection against gastric lesions of 100% in the three concentrations and lansoprazole 75%. In RLA, P. alata showed 100% of protection and lansoprazole 76.92%. P. nitida showed, in TLA, protection against gastric lesions of 25%,74% and 94% in the three concentrations, respectively and lansoprazole 80%. In RLA, nitida showed 27.40%, 74.00% and 91.78% of protection, respectively and lansoprazole 78.08%. Based upon this study it is possible to distinguish both species by leaf and stem morphoanatomic characters and by chromatographic profile. Both species presented promising antiulcer activity.

Page generated in 0.3134 seconds