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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Effect of albendazole against different stages of Angiostrongylus cantonensis in Sprague-Dawley rats and analyses of immune response after treatment

Lai, Pang-Yueh 15 July 2005 (has links)
This study evaluates the efficiency of albendazole against different stages of Angiostrongylus cantonensis in Sprague-Dawley rats. Using a single oral dose of albendazole of 10 mg/kg at 0 or 1 or 2 or 3 weeks post-infection (PI) showed that the drug in 0 or 1 weeks PI was more effective in the larval infection. Compared to those in non-treated control, the rats treated 0 or 1 weeks PI showed significant reductions not only in the relative wet weight of heart and lungs (g/100 g body weight), but also in the mean number of adults recovered. With regard to single oral doses of 10 or 50 or 100 mg/kg at weekly intervals from 6 weeks PI, the rats treated 100 mg/kg in 2 weeks post-treatment (PT) showed significant reduction in the L1 in its feces and the amounts were lastingly few. In the rats treated 10 or 50 mg/kg, larval output reappeared from 4 weeks PT. The histomorphology of granuloma formation was also investigated in the lungs of SD rats infected with A. cantonensis¡@by paraffin section. It was observed that granulomatous fibros was strongly associated with the number of L1 in the lungs. IgG and IgE antibodies specific for antigens from L1, L5, male worms or female adults of A. cantonensis were respectively measured by an enzyme-linked immunosorbent assay (ELISA). The specific IgE response to antigens from L1 or female adults of A. cantonensis in the serum reached the maximum at 1 and 5 weeks PI. Similarly, the eosinophil response also revealed remarkable peaks at 1 and 5 weeks PI. These results might prove that the increases of IgE titer and eosinophil are related to antibody-dependent cell mediated cytotoxicity (ADCC).
2

An investigation into the effects of albendazole on human ovarian carcinoma cells

Chu, Stephanie Wai Ling, Clinical School - St George Hospital, Faculty of Medicine, UNSW January 2007 (has links)
Paclitaxel (PTX) is an effective anti-mitotic drug. It stops cancer from spreading by interfering with the microtubule dynamics which in turn leads to cell cycle arrest and eventually cell death. Despite the clinical success in treating different types of cancers, resistance to PTX remains a major hurdle for successful treatment in relapse patients. Albendazole (ABZ) is a popular anthelmintic used world-wide for the treatment of various types of helmintic infections. In helminthes, ABZ binds to ??-tubulin and inhibits microtubule polymerisation. It was subsequently found that ABZ has anti-cancer activity. This study was carried out to study the effects of ABZ on PTX sensitive and PTX resistant human ovarian carcinoma cells. Cell growth assays revealed that the anti-proliferative activity of ABZ was not only effective on the PTX-sensitive human ovarian carcinoma cell line lA9, but also on its PTX-resistant sub-line, lA9PTX22. The ICso values of ABZ in lA9 and lA9PTX22 were 205 nM and 322 nM, respectively. Confocal images demonstrated that ABZ disrupted the microtubule network and caused formation of short microtubule bundles in both cell lines. Further analysis using tubulin polymerisation assay showed that the percentage of polymerised tubulin in lA9 and lA9PTX22 was increased by 58.9 % and 20.6 % respectively. Together, these results revealed for the first time that ABZ interacts with microtubules in human cancer cells and causes their polymerisation. It was also demonstrated that ABZ increased the release of cytochrome c, an important component of the intrinsic pathway in apoptosis. It was found that the expression of Bim, a BH-3 only pro-apoptotic protein was not elevated after ABZ treatment. The results presented in this study provide some information on the effect of ABZ on the microtubule network which could relate to its apoptotic effect in human ovarian carcinoma cells.
3

Avaliação comparativa de duas formulações anti-helmínticas em caprinos naturalmente infectados

Lima, Juliana Alves [UNESP] 30 July 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-07-30Bitstream added on 2014-06-13T19:55:40Z : No. of bitstreams: 1 lima_ja_me_jabo.pdf: 145215 bytes, checksum: 050e95ab3fc21a0c75221f6fbc659e0b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Avaliou-se no presente trabalho, a eficácia de dois antiparasitários: Moxidectina 1 % e a associação de (Albendazol + Levamizole + Ivermectina) no tratamento de nematódeos gastrintestinais de caprinos naturalmente infectados, da região de JaboticaballSP. Animais diagnosticados com infecção de nematódeos gastrintestinais, por meio de contagens de ovos por grama de fezes (OPG) superior a 500, foram randomizados e distribuídos em três grupos de 8 caprinos: Grupo I: Moxidectina 1 %, (200mcg/Kg) injetável, via subcutânea, na dose 1 mU50Kg; Grupo 11: Associação (Albendazole + Hidroclorido de Levamizole + Ivermectina) via per os, 1mU4Kg e Grupo 111: Controle (Solução Fisiológica) 1mU50Kg, via subcutânea. Após sete dias os animais foram eutanasiados e necropsiados para colheita, identificação e contagem dos helmintos. As espécies encontradas foram: Haemonchus contortus, Trichostrongy/us. co/ubriformis, T. axei, Oesophagostomum co/umbianum, Trichuris ovis e Capillaria bovis, sendo o H. contortus e T. co/ubriformis os mais expressivos com 57,49% e 47,25%, respectivamente. A associação demonstrou eficácia superior a 99% sobre as seis espécies, atingindo 100%, contra quatro delas, enquanto a moxidectina, em apenas quatro, obtendo eficácia máxima apenas contra duas espécies. / The efficiency of two anti-parasitic has been assessed in the present study: Moxidectin -1 % and the association of (Albendazole + Levamizole + Ivennectine) in the treatment of gastro-intestinal nematodes in naturally infected caprines in the region of Jaboticabal/SP. Animais diagnosticated whit gastro-intestinal nematode infection, by the count of eggs per gram of stools (EPG) superior to 500, were randomized and distributed in three groups of 8 caprines: Group I: Moxidectin 1 %, (200mcg/Kg), inserted, via sub-cutaneous, administered at a dose of 1 mU50kg; Group 11: Association of (Albendazole + Hydrochloridric Levamizole + Ivennectine) via peros, 1 mU4Kg and Group 111: Control (Fisiologic Solution) 1 mU50Kg, via subcutaneous. After seven days, the animais were euthanasied and necropsied for the harvest, identification and counting of helmints. The found species were: Haemonchus contortus, Trichostrongy/us co/ubriformis, T. axei, Oesophagostomun co/umbianum, Trichuris ovis and Capillaria bovis, finding that H. contortus and T. co/ubriformis are the most expressive ones whit 57,49% and 47,25% respectively. The association showed efficacy superior to 99% over the six species, reaching 100% against four, whereas moxidectin, only four, obtaining the maximum against two species.
4

Treatment and prevention of trichuriasis : efficacy of albendazole in disadvantaged children at Rawsonville Primary School, Western Cape Province, South Africa

Arendse, Vera Jane 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: Children in socioeconomically disadvantaged communities in the Western Cape and elsewhere in South Africa are frequently infected by Trichuris trichiura. Although albendazole and mebendazole are listed as essential drugs for treatment of humans, it is well known that trichuriasis is relatively refractory to anthelmintic treatment. There are some reports that mebendazole is more effective against Trichuris and it is available as generics that are relatively cheap. On the other hand, albendazole is better for hookworm and may have some effect against Giardia duodenalis, which is common in the same communities. Moreover, albendazole is used in a deworming programme in KwaZulu-Natal, at a dose o f400 mg stat, given once or twice a year depending on the health region in that province. In terms of diagnosis, infection by intestinal helminthiasis can be determined and monitored by simple, non-invasive, sustainable and cost effective methods. The epidemiological significance of high prevalence extends far beyond the worms per se because they are an index of environmental conditions that pose a risk of several other diseases. These include infection by organisms that can cause epidemics of enteric disease. These facts pertain within a deteriorating milieu in terms of human ecology, because the informal sector of the population is burgeoning under dynamic forces that include urbanisation, migration, poverty and disease. The study reported in this thesis had three main objectives within the context and concepts of the realities described in the previous two paragraphs. The first was to review and consider all information on trichuriasis that could be detected in the literature, and to relate the result to South African needs. The second was to test efficacy of albendazole against trichuriasis in children from a community where it is the predominant worm infection, by means of a well designed and controlled study. Finally, it was necessary to consider other results associated with treatment. These included possible drug resistance and effects on growth, eosinophilia, iron status and toxicity. The literature survey established that South Africa lags behind many other developing countries in defining and addressing the problem of helminthiasis as a whole. The conventional epidemiology of trichuriasis as described in the literature is based mainly on studies in the West Indies. Surveys completed recently in the Western Cape Province of South Africa confirm some of the epidemiological concepts, with two notable exceptions. First, the age-related prevalence peaked in children who were 14 years old in a suburb of Cape Town. This is older that in West Indian children. The second difference is probably more important and was detected in children at schools serving the informal sector o f Khayelitsha. This is densely populated and the sanitation is often not effective and is sometimes totally lacking. The distribution of egg counts in 316 Khayelitsha children was not overdispersed to low counts, which is perceived as invariably the situation in the West Indies. In the Khayelitsha survey, approximately 25% of children had more than 10 000 eggs per g of faeces. The randomised controlled treatment trial tested a series of four albendazole treatments, at doses of400, 800 and 1200 mg (given as 400 mg/day), repeated at intervals of approximately four months in matched groups of children. Results indicate that mass deworming programmes in South Africa should not use albendazole at a dose o f400 mg stat for control of infection by Trichuris trichiura. The package insert of the product tested (Zentel®, SmithKline Beecham) recommends that "in heavy mixed infestation involving Trichuris, a single daily dose may be inadequate and the dose may be given for three consecutive days". This statement is not accurate because even when infection by Trichuris was not intense, as defined internationally in terms of egg counts per g of faeces, and it was the only helminth present, the cure rate achieved by repeated doses of 400 mg of albendazole was not satisfactory. Moreover, 48% (15/31) of treated children remained continuously infected, although egg counts were clearly reduced. This result demonstrates that continuous use of a dose of 400 mg which is the maximum stat dose permitted in South Africa, is likely to facilitate development of true genetic resistance to albendazole by T. trichiura. Doses of 800 and 1200 mg were more efficacious and continuous infection reduced to 21% (9/43) and 2.5% (1/39), respectively. A dose of 800 mg for routine use in mass deworming programmes, as 400 mg/day, can be recommended on the basis of sufficiently efficacious treatment, simplification of compliance, and reduction of cost. The frequency of treatment within such programmes should probably be three times per year when prevalence of severe infection exceeds 10% ("severe infection" is defined internationally as an egg count of more that 10 000 per g of faeces). When severe infection is less frequent, treatment could be less often, but more definitive research of this aspect is necessary under local conditions. There was some evidence that incidence increased seasonally during summer and autumn in the community concerned. A range of other results was recorded. The possibility of genetic resistance to albendazole by Trichuris trichiura was not excluded. There was significant reduction of eosinophiha during treatment with albendazole. This may have immunological implications for incidence, prevention and progression of other diseases. Treatment appeared to be beneficial in terms of growth and iron status, but there was not sufficient statistical power to confirm this. No evidence of toxicity at the highest dose (1200 mg given as 400 mg/day for three days) was detected. / AFRIKAANSE OPSOMMING: Kinders in sosio-ekonomiese agterblewe gemeenskappe in die Wes-Kaap en ook elders in Suid-Afrika toon gereelde infeksies met Trichuris trichiura. Albendazool en mebendazool word gelys as noodsaaklike medikasie vir menslike behandeling, maar dit is wel bekend dat Trichuris relatief moeilik is omte behandel. Daar word gerapporteer dat mebendazool meer effektief is teen Trichuris en maklik beskikbaar is as goedkoper generiese medikasie. Albendazool, aan die ander kant, is effektief teen haakwurm en kan ook ‘n effek het teen Giardia duodenalis, wat voorkom in dieselfde gemeenskappe. ‘n Dosis van 400 mg albendazool, een of twee keer per jaar, word huidelik gebruik in ‘n onwurmingsprogram in KwaZulu-Natal. Die frekwensie van behandeling word bepaal deur die gesondheids streek binne die provinsie. In terme van diagnose, kan infeksie deur intestinale helminte bepaal en gemonitor word deur eenvoudige, nie-invallende, koste effektiewe maniere. Die epidemiologiese betekenis van ‘n hoe voorkoms strek verder as net die wurms omdat hulle ‘n indeks is van omgewings besoedeling wat kan dui op die risiko van verskeie ander siektes. Dit sluit in infeksies deur organismes wat epidemies van enteriese siektes veroorsaak. Hierdie feite pas binne die agteruitgang in terme van menslike ekologie, want die informele sektor van die bevolking is onder dinamiese druk wat verstedeliking, migrasie armoede en siektes insluit. Die studie, waarvan verslag gegee word in hierdie tesis, het drie vemame objektiewe binne die konteks en konsepte van die realiteite soos beskryf in die vorige twee paragrawe. Die eerste objektief was om alle informasie aangaande trichuriase in die literatuur in oorsig te neem en dit in verband te bring met Suid-Afrikaanse behoeftes. Die tweede was om die werksaamheid van albendazool teen trichuriase te toets in kinders van ‘n gemeenskap waar wurm infeksies oorheers, deur middel van ‘n goed beplande en gekontroleerde studie. Laastens was dit nodig om ander resultate, geassosieer met behandeling, in ag te neem. Dit sluit in moontlike weerstand teen die medikasie en die effek op groei, ysterstatus en toksisiteit. Die literatuur oorsig toon dat Suid-Afrika ‘n agterstand het met baie ander ontwikkelende lande om die omslag van die probleem van helminte te bepaal en ook om dit aan te pak. Die konvensionele epidemiologie van trichuriase, soos beskryf in die literatuur, is gegrond op studies in die Wes-Indies. Opnames wat onlangs in die Wes-Kaap gedoen is, bevestig sekere epidemiologiese konsepte met twee vemame uitsonderings. Die eerste is die ouderdoms verwante voorkoms wat ‘n hoogtepunt bereik in 14 jarige kinders in ‘n voorstad van Kaapstad. Dit is ouer as in die Wes-Indiese kinders. Die tweede verskil is miskien meer belangrik en was vasgestel in skool kinders in ‘n informele sektor van Khayelitsha. Dit is ‘n dig bewoonde area met oneffektiewe of ‘n totale gebrek aan sanitasie. Die verspreiding van eier tellings in 316 Khayelitsha kinders was nie oor-versprei tot lae tellings nie, wat andersins die geval in die Wes-Indies was. In die Khayelitsha studie het ongeveer 25% van kinders meer as 10 000 epg stoelgang. Die gekontrolleerde ewekansigheidstoets soos bespreek in hierdie tesis het ‘n reeks van vier albendazool behandelings, by dosisse van 400, 800 en 1200 mg (gegee as 400 mg/dag), herhaal by pouses van ongeveer vier maande in gelyke groepe van kinders, ge-evalueer. Die resultate toon dat massa ontwurmings programme in Suid-Afrika nie die 400 mg dosis vir kontrole van Trichuris trichiura moet gebruik nie. Die pakkie insetsel van die produk wat getoets was (Zentel®, SmithKline Beecham) dui aan dat in swaar gemengde infeksies waar Trichuris betrokke is, ‘n enkele dosis onvoldoende is en dat die dosis vir drie agtereenvolgende dae gegee mag word. Hierdie stelling is onakkuraat want al is die infeksie deur Trichuris nie swaar nie, soos intemasionaal gedefinieer in terme van eier telling per gram stoelgang, en al is dit die enigste intestinale wurm teenwoordig, is die genesingsyfer wat behaal is met herhaalde dossise van 400 mg albendazool nie bevredigend nie. Inteendeel, 48% (15/31) van behandelde kinders was aanhoudend besmet, al was eier tellings duidelik verminder. Hierdie resultaat wys dat herhaaldelike gebruik van ‘n 400 mg dosis, wat die maksimim dosis toelaatbaar in Suid-Afrika is, genetiese weerstand van albendazool deur Trichuris trichiura kan fasiliteer. Die 800 mg en 1200 mg dosis was meer doeltreffend en het herhaalde infeksie verminder tot 21 % (9/43) en 2.5% (1/39) onderskeidelik. Die 800 mg dosis as 400 mg/dag word aanbeveel vir roetine gebruik in massa ontwurmings programme. Dit is meer doeltreffend, behandeling word vereenvoudig en koste word verminder. Die frekwensie van behandeling binne sulke programme moet waarskynlik drie keer per jaar wees wanneer die prevalensie van swaar infeksies meer as 10% is (“swaar infeksie” word intemasionaal gedefinieer, wanneer eier tellings meer as 10 000 eiers per g stoelgang is). As swaar infeksies minder voorkom, kan behandeling minder gereeld wees, maar meer bepaalde navorsing onder plaaslike kondisies is nodig. Daar is sekere bewysse dat insidensie seisoenaal verminder, tydens somer en herfs, in hierdie gemeenskap. ‘n Reeks van ander resultate was ook aangeteken. Die moontlikheid van genetiese weerstand van Trichuris trichiura teen albendazool word nie uitgesluit nie. Daar was ‘n aanmerklike vermindering van eosinophillia tydens behandeling met albendazool. Dit mag immunologiese implikasies vir insidensie, voorkoming en voortgang van ander siektes voorspel. Dit blyk of behandeling groei en yster status bevoordeel het, maar daar was nie genoegsame statistiese mag om dit te bevestig nie. Geen bewys van vergiftiging by die hoogste dosis (1200 mg gegee as 400 mg/dag vir drie dae) is waargeneem nie.
5

Microencapsulação do sulfóxido de albendazol: uma estratégia para otimização da terapia das parasitoses / Microencapsulation of albendazole sulphoxide: a strategy to optimize the therapy of parasitosis

Souza, Marina Claro de 04 March 2009 (has links)
As parasitoses causadas por helmintos constituem um grave problema sanitário, tanto para os seres humanos quanto para os animais, além de gerar grandes prejuízos econômicos. O sulfóxido de albendazol é um fármaco anti-helmíntico de amplo espectro, largamente utilizado na medicina veterinária, veiculado pelas vias oral e parenteral, mediante a utilização de formas farmacêuticas convencionais. Apresenta biodisponibilidade baixa e irregular em função de sua pouca solubilidade nos fluidos biológicos. Para a manutenção da concentração plasmática e completa eliminação dos parasitos, são necessárias administrações reiteradas, ocasionando transtornos decorrentes do manejo freqüente dos animais e do aumento do custo da terapia. O presente trabalho teve como objetivo desenvolver e caracterizar um sistema microparticulado para liberação sustentada de sulfóxido de albendazol, de modo que este pudesse permanecer no organismo dos animais pelo tempo suficiente para a completa eliminação dos parasitos após uma única administração. Os sistemas foram obtidos a utilizando as técnicas de spray-drying e emulsificação / evaporação de solvente, tendo sido utilizados os polímeros Eudragit RS 30 D® e Eudragit RS PO®, respectivamente. As micropartículas obtidas foram caracterizadas com relação ao tamanho, à morfologia e à eficiência de encapsulação. Através da técnica de emulsificação / evaporação de solvente, foram obtidas partículas com diâmetro médio inferior a 300nm, estreita faixa de distribuição de tamanho e eficiência de encapsulação de aproximadamente 60%. Os resultados do estudo in vitro do perfil de liberação do fármaco a partir das micropartículas obtidas mostraram que, apesar de o sistema desenvolvido não ter sido capaz de sustentar a liberação do fármaco, o mesmo promoveu um aumento significativo da solubilidade do sulfóxido de albendazol em pH 7,4, fato este que pode contribuir para o aumento da biodisponibilidade do mesmo após administração parenteral. / The helminthosis are a serious sanitary problem, as for the men than for the animals, besides the great economic lacks. Albendazole sulphoxide is an antihelminthic drug with broad spectrum of action, widely used at veterinarian medicine, throw oral and parentereal vies, in conventional pharmaceutical dosages. It has low and irregular bioavailability due its low solubility in the biological fluids. For the maintenance of the plasmatic concentration and complete elimination of the parasites, it is required several administrations, creating many troubles due the frequent handling of the animals and increase in the costs of the therapy. The present work had as objective to develop and characterize microparticles for sustained release of albendazole sulphoxide, in order that the drug could be for a longer time in the animals organisms and the parasites could be eliminated after just one administration. The referred microparticles were obtained from the spray-drying and emulsification / evaporation of solvent techniques, using the polymers Eudragit RS 30 D® and Eudragit RS PO®, respectively. The obtained systems were characterized considering size, morphology and encapsulation efficiency. Using the emulsification / evaporation of solvent technique, it was prepared microparticles with medium diameter under 300nm, narrow range of size distribution and encapsulation efficiency of about 60%. The results of the in vitro release profile study of the drug from the prepared microparticles showed that besides the developed system was not be able to sustain the drug delivery, it was able to improve significantly the solubility of albendazole sulphoxide at pH 7.4, what can be useful to improve its parenteral bioavailability.
6

Caracterização físico-química e desenvolvimento de metodologia para avaliação da dissolução intrínseca de albendazol e mebendazol / Physicochemical characterization and development of methodology for the evaluation of the intrinsic dissolution of albendazole and mebendazole

Roque Flores, Roxana Lili 03 October 2011 (has links)
O presente trabalho teve como objetivo desenvolver metodologia para avaliação da dissolução intrínseca (DI) de amostras de albendazol (ABZ) e mebendazol (MBZ), empregando-se o método de disco rotativo. Inicialmente foi realizada a caracterização físico-química dos fármacos, empregando-se os ensaios de termogravimetria (TG), calorimetria exploratória diferencial (DSC), difratometria de raios X (DRX), microscopia eletrônica de varredura (MEV), densidade verdadeira, área superficial e tamanho de partícula, para sete amostras de ABZ e oito de MBZ. Com as análises de DRX e DSC foi possível verificar a presença dos polimorfos I e II, além de outras estruturas cristalinas nas amostras de ABZ. Em relação ao MBZ foi possível identificar os polimorfos A, C e a mistura destes polimorfos. Mediante o ensaio de solubilidade, verificou-se que as amostras que possuem o polimorfo C foram as mais solúveis nos meios de HCl 0,1N e suco gástrico. Finalmente, desenvolveu-se a metodologia para a avaliação da DI de ABZ e MBZ. Para avaliar o impacto das condições de ensaio na DI, escolheu-se uma amostra de ambos fármacos, que foi submetida a diferentes ensaios conforme delineamento experimental ortogonal de Taguchi do tipo L9(34). Verificou-se que tanto para o ABZ quanto para o MBZ, a variável que apresentou maior impacto na velocidade de dissolução intrínseca (VDI) foi o meio de dissolução. Dessa maneira, selecionaram-se as condições para a realização dos ensaios comparativos entre as amostras (diferentes fornecedores). Observou-se que as amostras que apresentam o polimorfo II (ABZ) e o C (MBZ) são aquelas que mostraram maiores valores de VDI. As condições empregadas para o estudo da VDI das amostras dos fármacos permitiram evidenciar diferenças entre os polimorfos demonstrando que a técnica de dissolução intrínseca é viável na caracterização das formas polimórficas de ABZ e MBZ. / The purpose of this study was to develop a methodology for evaluating the intrinsic dissolution (ID) of samples of albendazole (ABZ) and mebendazole (MBZ), employing the rotating disk method. Initially, a physicochemical characterization of seven samples of ABZ and eight samples of MBZ was carried out through thermogravimetric tests (TG), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and scanning electron microscopy (SEM), as well as evaluations of true density, surface area and particle size. With the XRD and DSC analyses, it was possible to ascertain the presence of polymorphs I and II, as well as other crystalline structures in the ABZ samples. With regards to MBZ, it was possible to identify polymorphs A and C, as well as a mixture of these polymorphs. With the execution of a solubility test, it was ascertained that the samples with polymorph C were the most soluble in the HCl 0.1N and gastric acid media. Finally, a methodology for the evaluation of the ID of ABZ and MBZ was developed. In order to evaluate the impact of the test conditions on ID, samples of both drugs were chosen, which were then subjected to different tests, according to the L9 (34) Taguchi experimental orthogonal array. It was ascertained that for both ABZ and MBZ, the variable with the greatest impact on the intrinsic dissolution rate (IDR) was the dissolution medium. Accordingly, the conditions for the execution of comparative tests between the samples were selected (different suppliers). It was observed that the samples that presented the polymorph II (ABZ) and C (MBZ) were also those that presented the greatest IDR values. The conditions employed for the IDR study of the drug samples enabled differences between the polymorphs to be ascertained, thus demonstrating that the intrinsic dissolution technique is viable for the characterization of polymorphic forms of ABZ and MBZ.
7

Avaliação comparativa de duas formulações anti-helmínticas em caprinos naturalmente infectados /

Lima, Juliana Alves. January 2006 (has links)
Orientador: Gilson Pereira de Oliveira / Banca: Oeliton Ferreira Barbosa / Banca: Adjair Antonio do Nascimento / Resumo: Avaliou-se no presente trabalho, a eficácia de dois antiparasitários: Moxidectina 1 % e a associação de (Albendazol + Levamizole + Ivermectina) no tratamento de nematódeos gastrintestinais de caprinos naturalmente infectados, da região de JaboticaballSP. Animais diagnosticados com infecção de nematódeos gastrintestinais, por meio de contagens de ovos por grama de fezes (OPG) superior a 500, foram randomizados e distribuídos em três grupos de 8 caprinos: Grupo I: Moxidectina 1 %, (200mcg/Kg) injetável, via subcutânea, na dose 1 mU50Kg; Grupo 11: Associação (Albendazole + Hidroclorido de Levamizole + Ivermectina) via per os, 1mU4Kg e Grupo 111: Controle (Solução Fisiológica) 1mU50Kg, via subcutânea. Após sete dias os animais foram eutanasiados e necropsiados para colheita, identificação e contagem dos helmintos. As espécies encontradas foram: Haemonchus contortus, Trichostrongy/us. co/ubriformis, T. axei, Oesophagostomum co/umbianum, Trichuris ovis e Capillaria bovis, sendo o H. contortus e T. co/ubriformis os mais expressivos com 57,49% e 47,25%, respectivamente. A associação demonstrou eficácia superior a 99% sobre as seis espécies, atingindo 100%, contra quatro delas, enquanto a moxidectina, em apenas quatro, obtendo eficácia máxima apenas contra duas espécies. / Abstract: The efficiency of two anti-parasitic has been assessed in the present study: Moxidectin -1 % and the association of (Albendazole + Levamizole + Ivennectine) in the treatment of gastro-intestinal nematodes in naturally infected caprines in the region of Jaboticabal/SP. Animais diagnosticated whit gastro-intestinal nematode infection, by the count of eggs per gram of stools (EPG) superior to 500, were randomized and distributed in three groups of 8 caprines: Group I: Moxidectin 1 %, (200mcg/Kg), inserted, via sub-cutaneous, administered at a dose of 1 mU50kg; Group 11: Association of (Albendazole + Hydrochloridric Levamizole + Ivennectine) via peros, 1 mU4Kg and Group 111: Control (Fisiologic Solution) 1 mU50Kg, via subcutaneous. After seven days, the animais were euthanasied and necropsied for the harvest, identification and counting of helmints. The found species were: Haemonchus contortus, Trichostrongy/us co/ubriformis, T. axei, Oesophagostomun co/umbianum, Trichuris ovis and Capillaria bovis, finding that H. contortus and T. co/ubriformis are the most expressive ones whit 57,49% and 47,25% respectively. The association showed efficacy superior to 99% over the six species, reaching 100% against four, whereas moxidectin, only four, obtaining the maximum against two species. / Mestre
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Caracterização físico-química e desenvolvimento de metodologia para avaliação da dissolução intrínseca de albendazol e mebendazol / Physicochemical characterization and development of methodology for the evaluation of the intrinsic dissolution of albendazole and mebendazole

Roxana Lili Roque Flores 03 October 2011 (has links)
O presente trabalho teve como objetivo desenvolver metodologia para avaliação da dissolução intrínseca (DI) de amostras de albendazol (ABZ) e mebendazol (MBZ), empregando-se o método de disco rotativo. Inicialmente foi realizada a caracterização físico-química dos fármacos, empregando-se os ensaios de termogravimetria (TG), calorimetria exploratória diferencial (DSC), difratometria de raios X (DRX), microscopia eletrônica de varredura (MEV), densidade verdadeira, área superficial e tamanho de partícula, para sete amostras de ABZ e oito de MBZ. Com as análises de DRX e DSC foi possível verificar a presença dos polimorfos I e II, além de outras estruturas cristalinas nas amostras de ABZ. Em relação ao MBZ foi possível identificar os polimorfos A, C e a mistura destes polimorfos. Mediante o ensaio de solubilidade, verificou-se que as amostras que possuem o polimorfo C foram as mais solúveis nos meios de HCl 0,1N e suco gástrico. Finalmente, desenvolveu-se a metodologia para a avaliação da DI de ABZ e MBZ. Para avaliar o impacto das condições de ensaio na DI, escolheu-se uma amostra de ambos fármacos, que foi submetida a diferentes ensaios conforme delineamento experimental ortogonal de Taguchi do tipo L9(34). Verificou-se que tanto para o ABZ quanto para o MBZ, a variável que apresentou maior impacto na velocidade de dissolução intrínseca (VDI) foi o meio de dissolução. Dessa maneira, selecionaram-se as condições para a realização dos ensaios comparativos entre as amostras (diferentes fornecedores). Observou-se que as amostras que apresentam o polimorfo II (ABZ) e o C (MBZ) são aquelas que mostraram maiores valores de VDI. As condições empregadas para o estudo da VDI das amostras dos fármacos permitiram evidenciar diferenças entre os polimorfos demonstrando que a técnica de dissolução intrínseca é viável na caracterização das formas polimórficas de ABZ e MBZ. / The purpose of this study was to develop a methodology for evaluating the intrinsic dissolution (ID) of samples of albendazole (ABZ) and mebendazole (MBZ), employing the rotating disk method. Initially, a physicochemical characterization of seven samples of ABZ and eight samples of MBZ was carried out through thermogravimetric tests (TG), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and scanning electron microscopy (SEM), as well as evaluations of true density, surface area and particle size. With the XRD and DSC analyses, it was possible to ascertain the presence of polymorphs I and II, as well as other crystalline structures in the ABZ samples. With regards to MBZ, it was possible to identify polymorphs A and C, as well as a mixture of these polymorphs. With the execution of a solubility test, it was ascertained that the samples with polymorph C were the most soluble in the HCl 0.1N and gastric acid media. Finally, a methodology for the evaluation of the ID of ABZ and MBZ was developed. In order to evaluate the impact of the test conditions on ID, samples of both drugs were chosen, which were then subjected to different tests, according to the L9 (34) Taguchi experimental orthogonal array. It was ascertained that for both ABZ and MBZ, the variable with the greatest impact on the intrinsic dissolution rate (IDR) was the dissolution medium. Accordingly, the conditions for the execution of comparative tests between the samples were selected (different suppliers). It was observed that the samples that presented the polymorph II (ABZ) and C (MBZ) were also those that presented the greatest IDR values. The conditions employed for the IDR study of the drug samples enabled differences between the polymorphs to be ascertained, thus demonstrating that the intrinsic dissolution technique is viable for the characterization of polymorphic forms of ABZ and MBZ.
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Benzimidazole-resistance and associated changes in life history traits of Heligmosomoides polygyrus (Nematoda) in mice

Chehresa, Azita. January 1996 (has links)
Association between albendazole anthelmintic resistance and a panel of life history traits in Heligmosomoides polygyrus was investigated both prior to and during drug-selection. Associations prior to anthelmintic application were studied in ten independent lines isolated without drug treatment from a susceptible stock population by random genetic drift. Variation among lines was detected in several life history traits (i.e., establishment, development and survival), and, despite lack of previous exposure to albendazole, lines also varied in their tolerance to the drug. No significant correlations were detected between drug-tolerance and any of the life history traits after 11 generations of isolation. The apparent lack of fitness differential between lesser and more drug-tolerant individuals of the susceptible population is not in accordance with the assumption that the low frequency of drug tolerant individuals in the susceptible population is explained by their lower fitness, but is consistent with the neutral theory. Associations between life history traits and drug resistance were also studied using two lines selected for albendazole resistance from the stock population, and two control lines exposed to the same monthly passage procedure but not to the drug. After 10 generations of selection, drug resistance increased from an LC50 of 0.48 $ mu$M to 2.03 $ mu$M. In a primary infection, the higher establishment and higher worm numbers one-month post-infection in the resistant parasites compared to the stock parasites occurred only in the drug-selected lines. Changes in these traits were attributed to the drug selection regime. In contrast, both drug-selected lines and passaged lines showed a faster rate of development and higher early egg production compared with the stock parasites; these changes were attributed to the passage procedure that presumably acted as a selective force on early life history traits. In immunized hosts, changes in several traits that o
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Cucurbit[n]uril - a delivery host for anti-cancer drugs

Zhao, Yunjie, Physical, Environmental & Mathematical Sciences, Australian Defence Force Academy, UNSW January 2009 (has links)
No description available.

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