To see the other types of publications on this topic, follow the link: Propionate.

Dissertations / Theses on the topic 'Propionate'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 dissertations / theses for your research on the topic 'Propionate.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.

1

Oliveira, Gabriela Bagio. "Frequência de fornecimento de narasina na nutrição de ovinos." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/10/10135/tde-03122018-113419/.

Full text
Abstract:
O consumo na dose correta e principalmente na frequência adequada são as principais dificuldades do fornecimento de ionóforos para animais em dietas com elevado teor de volumoso. O objetivo do estudo foi avaliar o efeito da frequência do fornecimento de narasina no desempenho (Exp. I), parâmetros de fermentação ruminal, digestibilidade aparente dos nutrientes e balanço de nitrogênio (Exp. II) em ovinos alimentados com dietas contendo elevado teor de volumoso. As dietas experimentais foram compostas por 95% de feno de coastcros e 5% de milho moído. Os tratamentos utilizados foram: Controle (C): fornecimento do concentrado uma vez ao dia sem ionóforo, Narasina 24 horas (N24): fornecimento diário de narasina na dosagem de 13 mg de narasina /kg de MS, Narasina 48 horas (N48): fornecimento de narasina a cada 48 horas (dias alternados), sendo no primeiro dia ofertado 26 mg de narasina/kg de MS e no segundo dia foi fornecido apenas o milho moído (média receberam 13 mg de narasina/kg de MS), Narasina 72 horas (N72): fornecimento de narasina a cada 72 horas, sendo no primeiro dia ofertado 39 mg de narasina/kg de MS, já no segundo e terceiro dia fornecido apenas o milho moído sem ionóforo. As análises estatísticas foram realizadas utilizando o procedimento MIXED do SAS (2002) e considerado efeito significativo quando P 0,05. Experimento I: Foram utilizados 44 cordeiros (33,31 ± 0,59 kg), sendo o delineamento experimental de blocos completos casualizados, com a duração de 105 dias. Não houve efeito para o CMS (P = 0,28), no entanto, a inclusão de narasina diariamente (N24) e a cada 48 horas (N48) aumentou o GMD dos animais (P = 0,03) e a EA (P = 0,02). Experimento II: Foram utilizados quatro borregos (Dorper x Santa Inês, castrados e providos de cânulas ruminais). O delineamento experimental utilizado foi o quadrado latino 4 x 4. O experimento teve duração total de 144 dias, divididos em quatro períodos de trinta e seis dias. Em cada período os doze primeiros dias foram utilizados como wash-out, do 13° ao 36° dia os animais receberam as dietas experimentais, a colheitas de dados (total de fezes, urina e de fluido ruminal) foram realizadas nos seis últimos dias de cada período. Não houve efeito na digestibilidade da MS e do FDN, os tratamentos N24 e N48 aumentaram a concentração molar de 11 propionato (P < 0,01), a concentração total de AGCC (P < 0,01) e diminuiu a relação acetato:propionato (P < 0,01). Com base nos dados obtidos é possível concluir que os tratamentos N24 e N48 aumentaram o peso final dos cordeiros, e alterou positivamente fermentação ruminal dos ovinos, por outro lado, a narasina mostrou diminuição na sua capacidade como moduladora da fermentação ruminal no intervalo de fornecimento maior que dois dias (72 horas/N72).
The intake on the correct dosage and frequency are the main difficulties of supplying ionophores for animals on high forage diets. Therefore, the aim of this study was to evaluate the frequency of supplementation of narasin over performance (Exp. I), ruminal fermentation parameters, nutrient apparent digestibility and nitrogen balance (Exp. II) on sheep fed high forage diets. The experimental diets consisted on 95% coastcross hay and 5% ground corn used as a delivery vehicle of the additive. The treatments were: Control (C): daily supply of concentrate without the ionophore; narasin 24 hours (N24): daily supply of 13 mg of narasin/kg of DM; narasin 48 hours (N48): supply of narasin every 48 hours (every other day), being provided 26 mg of Narasin/kg of DM on the first day and only the ground corn on the second day (an average of 13 mg of narasin/kg of DM); narasin 72 hours (N72): supply of narasin every 72 hours (one day receiving the additive followed by two days without receiving it), being provided 39 mg of narasin/kg of DM on the first day and only the ground corn on the second and third days. The statistical analysis was done using the MIXED procedure on SAS (2002) and the effects were considered significant when P 0.05. Experiment I: Were used 44 lambs (33.31 ± 0.59 kg) in a randomized block experimental design, the trial lasted 105 days. There was no effect for DMI (P = 0.28), the daily inclusion of narasin (N24) and every 48 hours (N48) increased the ADG (P = 0.03) and the FE (P < 0.01). Experiment II: Were used 4 male lambs (Dorper x Santa Inês, castrated and cannulated in the rumen) in a 4 x 4 Latin square experimental design. The trial lasted 144 days, divided in 4 periods of 36 days each. The first twelve days of each period were used as wash-out, from the 13th to the 36th day the animals received the experimental diets, and the data collection (feces, urine and ruminal fluid) were done on the last six days of each period. . It was not the effect on the digestibility of DM (P = 0.30) and NDF (P = 0.14). The daily inclusion of narasin (N24) and every 48 hours (N48) increased the molar concentration of propionate (P < 0.01), the total concentration of SCFA (P <0.01) and reduced the acetate to propionate (acetate:propionate ratio) ratio (P < 0.01). Based on this data it was possible to 13 conclude that the daily supply of narasin (N24) and every 48 hours (N48) affected the performance and ruminal fermentation parameters on sheep, but this effects decreased when intervals bigger than 48 hours (N72) were used.
APA, Harvard, Vancouver, ISO, and other styles
2

Ali, H. R. H., Howell G. M. Edwards, John Kendrick, and Ian J. Scowen. "Vibrational spectroscopic study of fluticasone propionate." Elsevier, 2009. http://hdl.handle.net/10454/4724.

Full text
Abstract:
No
Luticasone propionate is a synthetic glucocorticoid with potent anti-inflammatory activity that has been used effectively in the treatment of chronic asthma. The present work reports a vibrational spectroscopic study of fluticasone propionate and gives proposed molecular assignments on the basis of ab initio calculations using BLYP density functional theory with a 6-31G* basis set and vibrational frequencies predicted within the quasi-harmonic approximation. Several spectral features and band intensities are explained. This study generated a library of information that can be employed to aid the process monitoring of fluticasone propionate.
APA, Harvard, Vancouver, ISO, and other styles
3

Polizel, Daniel Montanher. "Utilização de narasina na nutrição de ovinos." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/10/10135/tde-19012018-095611/.

Full text
Abstract:
Os ionóforos possuem papel importante como manipuladores da fermentação ruminal, principalmente por melhorar a eficiência energética e proteica nos animais ruminantes. A narasina é um ionóforo capaz de fazer controle microbiológio no ambiente ruminal. Entretanto, a literatura possui poucas informações sobre a utilização de narasina na nutrição de ovinos. O presente trabalho teve como objetivos avaliar a utilização de doses de narasina em dietas de ovinos alimentados contendo elevado teor de concentrado ou volumoso. A hipotese é que a narasina tenha a capacidade de alterar os produtos finais da fermentação ruminal, melhorando a utilização dos nutrientes e o metabolismo de nitrogênio de ovinos. No Exp I os tratamentos experimentais foram definidos de acordo com a inclusão ou não de aditivos na dieta contendo elevado teor de concentrado, sendo utilizado uma dieta Controle (C), em que não houve a inclusão de ionóforo; a adição de 25 ppm de monensina sódica (M); 5 ppm (N5); 10 ppm (N10); e 15 ppm de narasina (N15). A inclusão de 5, 10 e 15 mg de narasina/kg de MS aumentou o ganho de peso e a eficiência alimentar de cordeiros alimentados durante 56 dias com dieta contendo 90% de concentrado. No Exp II foram avaliadas as mesmas dietas do exp I. A inclusão de 5, 10 e 15 mg de narasina/kg de MS reduziu o CMS e aumentou o coeficiente de digestibilidade aparente dos nutrientes da MS, MO, PB, gordura e CNF. Além disso, após o período de adaptação houve efeito quadrático para a proporção molar de acetato e a relação acetato:propionato com o aumento das doses de narasina, entretanto, não alterou o pH ruminal. As doses de narasina reduziram linearmente a concentração de amônia no fluido ruminal. A inclusão de narasina nas dietas de borregos tendeu a diminuir o consumo de nitrogênio e reduziu a eliminação de nitrogênio pelas fezes e pela urina. No Exp III os tratamentos foram definidos pela inclusão de doses de narasina em dietas contendo elevado teor de volumoso, sendo o tratamento controle (N0: sem a adição de ionóforo) e a inclusão de 8, 16, 24 e 32 mg de narasina/kg de MS. A inclusão de 0, 8, 16, 24 ou 32 mg de narasina/kg de MS em dietas de borregos alimentados com elevado teor de volumoso não afetou o consumo de matéria seca e tendeu a aumentar linearmente o coeficiente de digestibilidade da FDN. As doses de narasina não alteraram a proporção molar de AGCC, entretanto aumentou a concentração total de AGCC e diminuiu linearmente a concentração de amonia no fluido ruminal. Com base nesses dados foi possivel concluir que a narasina pode ser utilizada em dietas de ovinos aumentando o desempenho dos animais.
Ionophores play an important role as ruminant fermentation manipulators mainly for improving energy and protein efficiency in ruminant. Narasin is an ionophore capable of making microbiological control in the ruminal environment. However, the literature has little information on the use of narasin in sheep nutrition. The objectives of this study were to evaluate the use of doses of narasin in diets of sheep fed diets containing high concentrate or forage contents. The hypothesis is that narasin has the ability to alter the final products of ruminal fermentation, improving nutrient utilization and nitrogen metabolism of sheep. In the Exp I the experimental diets were defined according of the inclusion or not of additives in the diet containing high concentrate, using a control diet (C: no ionophore); the addition of 25 mg of monensin/kg of DM (M); 5 (N5), 10 (N10) or 15 mg of narasin/kg of DM. The inclusion of 5, 10 and 15 mg of narasin / kg of DM increased the average daily gain and feed efficiency of lambs fed for 56 days on a diet containing 90% concentrate. In the Exp II were evaluated the same diets used in the Exp I. The inclusion of 5, 10 and 15 mg narasin / kg DM reduced CMS and increased the apparent digestibility coefficient of DM, OM, CP, fat and NFC. In addition, after the adaptation period there was a quadratic effect for the molar proportion of acetate and the acetate: propionate ratio with increasing doses of narasin, however, did not alter the ruminal pH. The doses of narasin linearly reduced the concentration of ammonia in the ruminal fluid. The inclusion of narasin in diets of wethers tended to reduce nitrogen consumption, and reduced the elimination of nitrogen through feces and urine. In the Exp III the experimental diets were defined by the inclusion of doses of narasin in diets containing high forage contend, being the control diets (N0: no ionophore), and inclusion of 8, 16, 24 or 32 mg of narasin/kg od DM. the inclusion of 0, 8, 16, 24 or 32 mg of narasin / kg of DM in diets of lambs fed with high volume did not affect dry matter intake and tended to linearly increase the NDF digestibility coefficient. Doses of narasin did not alter the molar ratio of AGCC, however increased the total concentration of AGCC in and decreased linearly the concentration of ammonia in the ruminal fluid. Based on these data it was possible to conclude that narasin can be use in sheep diets to improve animal performance
APA, Harvard, Vancouver, ISO, and other styles
4

De, Wet Martie. "The effect of colonic propionate and the acetate : propionate ratio on risk markers for cardiovascular disease in westernised African men." Thesis, Bloemfontein : Central University of Technology, Free State, 2009. http://hdl.handle.net/11462/30.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Holland, Gail Skene. "Diversity of propionate producing bacteria from the pig gastrointestinal tract." Thesis, University of Aberdeen, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.493590.

Full text
Abstract:
Early weaning and a reduction in the use of antimicrobial growth promoters tend to increase the risk of enteric disease during a period when young pigs are particularly vulnerable, not least due to their immature gastrointestinal and immune systems. Additionally, young animals have yet to acquire a stable, mature commensal microflora. This study examined anaerobic bacterial groups and species present in the different sections of the porcine gastrointestinal tract (GIT), and attempted to identify components of the healthy microflora that might be used to reduce the risk of disease through prophylactic use as probiotics.
APA, Harvard, Vancouver, ISO, and other styles
6

Fauzee, Ayeshah Fateemah Beebee. "Development, manufacture and assessment of Clobetasol 17-propionate cream formulations." Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1013324.

Full text
Abstract:
Eczema or dermatitis is the most common dermatological condition accounting for one-third of all diagnoses in the total population surveyed in South Africa. The prevalence of seborrhoeic dermatitis, extreme photodermatitis and severe psoriasis has increased markedly over the last decade and this increase may be ascribed to the HIV epidemic, first diagnosed in South Africa in 1982. Potent innovator corticosteroids, such as clobetasol 17-propionate (CP) that are used to treat skin disorders, are expensive and there is therefore a need for the production of generic topical corticosteroid products. Formulation and manufacturing processes can be challenging aspects for formulation scientists to produce a robust product that will elicit an appropriate and desirable pharmacokinetic-pharmacodynamic profile. Laboratory scale CP creams were manufactured using different concentrations of Gelot® 64 and propylene glycol in order to establish a composition that would produce a formulation, with similar physical and chemical characteristics and in vitro release profile as an innovator product, Dermovate®. These formulations were assessed in terms of their viscosity, spreadability, pH, content uniformity and in vitro release characteristics using a Franz diffusion cell apparatus. A formulation containing 3% w/w Gelot® 64 and 46% v/v propylene glycol (CPLS-02) was found to exhibit similar viscosity and spreadability characteristics and released CP in a manner similar to Dermovate®. The mechanism of drug release was evaluated using mathematical models such as zero order, first order and Higuchi models. In addition, the in vitro release profiles were characterised by use of difference (f1) and similarity (f2 and Sd) factors. A scale-up formulation with the same % w/w composition as the laboratory scale was also investigated following manufacture using a Wintech® cream/ointment mixer. A Central Composite Design approach was used to investigate the effect of process variables on the performance of the scale-up cream formulations. The homogenisation speed, anchor speed, homogenisation time and cooling time were the process variables investigated. Thirty scale-up batches were manufactured and analysed in terms of their viscosity, spreadability, pH, % drug content and cumulative % drug released per unit area over 72 hours. Model fitting using Design-Expert® software was undertaken and revealed that a correlation between the process variables and the cream responses was most suitably described by quadratic polynomial relationships. The homogenisation speed had the most significant effect on the quality of the scale-up formulations, whereas the anchor speed had a secondary effect on the measured responses, for the formulations investigated. The qualitative interpretation and statistical analysis of the in vitro release data from the scale-up formulations using ANOVA and the f1, f2 and Sd factors revealed that one scale-up batch (CPSU-04), for which the process variables were a homogenisation speed of 1900 rpm, an anchor speed of 35 rpm, a homogenisation time of 100 minutes and a cooling time of 100 minutes, released CP at a similar rate and extent to Dermovate®. A diffusion-controlled mechanism appeared to be predominant in these formulations. A human skin blanching study, using both visual and chromameter assessments, was performed to establish whether batch CPSU-04 was bioequivalent to Dermovate®. The bioequivalence of the selected scale-up formulation to Dermovate® was confirmed, following the calculation of a 90% CI.
APA, Harvard, Vancouver, ISO, and other styles
7

Besnier, Sandrine. "Propionate de fluticasone : corticoïde inhalé dans le traitement de l'asthme." Bordeaux 2, 2000. http://www.theses.fr/2000BOR2P021.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Ohl, Jean. "Hepatotoxicite du propionate d'erythromycine : a propos de trois observations personnelles." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR1M147.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Fontana, Márcia Camponogara. "NANOPARTÍCULAS CONTENDO PROPIONATO DE CLOBETASOL: PREPARAÇÃO, CARACTERIZAÇÃO E INCORPORAÇÃO EM HIDROGÉIS." Universidade Federal de Santa Maria, 2010. http://repositorio.ufsm.br/handle/1/5911.

Full text
Abstract:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The aim of this work was the development of nanostructured formulations containing clobetasol propionate. Initially, it was validated a chromatographic method to assay clobetasol propionate in nanocapsule suspensions. Clobetasol propionate-loaded nanocapsules and nanospheres of poly(ε-caprolactone) (PCL) and nanoemulsion (0.5 mg mL-1) were prepared by the interfacial deposition of preformed polymer method, nanoprecipitation and spontaneous emulsification, respectively. Formulations were characterized by means of drug content, encapsulation efficiency, pH, mean size, polydispersity index, zeta potential, morphology analysis, and stability under storage. The PCL nanocapsules showed the highest physicochemical stability, followed by the nanoemulsions and nanospheres. In the evaluation of in vitro release of clobetasol propionate, the nanocapsules showed a better control of drug release, according to the biexponential model. The photodegradation study of clobetasol propionate against UVA light showed the importance of the polymer and the oil in the nanoparticles to protect the drug from light. From these results, the nanocapsules were chosen for the study of the influence of the polymerid material on the physicochemical stability umder storage, photostability, release profile of the drug and its release mechanism. The nanocapsules prepared with poly(lactide) (PLA) showed a higher stability in comparison to the nanocapsules prepared with poly(lactide-co-glycolide) 50:50 and 85:15, although its stability was lower than nanocapsules prepared with PCL. Photodegradation studies demonstrated the pretection of the nanoencapsulated drug, regardless of the polymeric material of the nanocapsule s wall. The in vitro release study demonstrated the controlled release of the drug according to an anomalous transport. Due to these results, the nanocapsules prepared with PCL were selected for the development and preparation of hydrogels. Similar formulations containing nanospheres and nanoemulsion were used to evaluate the influence of polymer and oil on different properties of the hydrogels. These dosage forms were evaluated for drug content, pH, spreadability, rheology and in vitro drug release. All hydrogels presented properties compatible to the topical application. The presence of the drug-loaded nanoparticles in hydrogels led a slower drug release, especially for the formulation containing nanocapsules. The drug release profile was according to the Higuchi model.
Este trabalho teve como principal objetivo o desenvolvimento de formulações nanoestruturadas contendo propionato de clobetasol. Inicialmente, foi validado um método cromatográfico para análise do propionato de clobetasol em suspensões de nanocápsulas poliméricas. As nanocápsulas e nanoesferas de poli(ε-caprolactona) (PCL) e nanoemulsões contendo propionato de clobetasol (0,5 mg/mL) foram preparadas pelo método da deposição interfacial do polímero pré-formado, nanoprecipitação e emulsificação espontânea, respectivamente. Foram avaliados teores de fármaco, eficiências de incorporação, pHs, diâmetros de partícula, índices de polidispersão, potenciais zeta, características morfológicas e estabilidade frente ao armazenamento das diferentes formulações. As nanocápsulas apresentaram maior estabilidade físico-química, seguida pelas nanoemulsões e nanoesferas. Na avaliação da liberação in vitro do propionato de clobetasol, as nanocápsulas apresentaram o maior controle na liberação do fármaco, seguindo um modelo biexponencial. O estudo da fotodegradação do propionato de clobetasol frente à luz UVA demonstrou a importância da presença do polímero e do óleo para o aumento da fotoestabilidade. Diante destes resultados, as nanocápsulas foram selecionadas para o estudo da influência do material polimérico sobre as características físico-químicas, estabilidade frente ao armazenamento, fotoestabilidade, perfil de liberação do fármaco e seu mecanismo de liberação. As nanocápsulas preparadas com poli(ácido lactídeo) (PLA) apresentaram uma maior estabilidade frente ao armazenamento em comparação com as nanocápsulas preparadas com poli(ácido lactídeo-coglicolídeo) 50:50 e 85:15, embora sua estabilidade tenha sido inferior às nanocápsulas preparadas com PCL. O estudo da fotodegradação demonstrou a proteção do fármaco quando nanoencapsulado, independente do tipo de polímero empregado na sua preparação. A liberação in vitro demonstrou a liberação controlada do fármaco com transporte anômalo. Diante de todos esses resultados, as nanocápsulas preparadas com PCL foram selecionadas para o desenvolvimento de formas farmacêuticas semissólidas (hidrogéis). Formulações similares contendo nanoesferas e a nanoemulsão foram utilizadas para se avaliar a influência do polímero e do óleo sobre diferentes propriedades dos hidrogéis. Estas formas farmacêuticas foram avaliadas quanto ao teor de fármaco, pH, espalhabilidade, reologia e liberação in vitro do fármaco. Os hidrogéis apresentaram propriedades compatíveis com a aplicação tópica. A presença do fármaco nanoencapsulado nos hidrogéis proporcionou sua liberação controlada, principalmente para as formulações contendo as nanocápsulas. O perfil de liberação do fármaco a partir dos hidrogéis seguiu o modelo de Higuchi.
APA, Harvard, Vancouver, ISO, and other styles
10

Tavassoli-Salardini, Fereshteh, of Western Sydney Nepean University, and Faculty of Science and Technology. "Inhibition of mild steel corrosion in aqueous media with sodium propionate." THESIS_FST_XXX_TavassoliSalardini_F.xml, 1996. http://handle.uws.edu.au:8081/1959.7/233.

Full text
Abstract:
The potential use of sodium propionate as a corrosion inhibitor for mild steel in aqueous media is investigated using a range of electrochemical and surface analytical techniques. The use of sodium propionate for the inhibition of mild steel corrosion is discussed, and the effective pH range of sodium propionate using various buffers is investigated. The effectiveness of sodium propionate as an inhibitor for mild steel pitting corrosion in the presence of various concentrations of CI- is studied. The effect of some oxidants, IO3-, BrO3-, NO32- on the anodic behaviour of mild steel in deaerated 0.01M carboxylate solutions of acetate, propionate, formate, succinate and salicylate is investigated. The critical temperature for effective inhibition of mild steel corrosion with sodium propionate is established, and the chemical composition of the film formed on mild steel surface in sodium propionate solution is studied using surface sensitive Fourier transform infrared spectroscopy FTIR. The efficiency of sodium propionate is compared to that of conventional inhibitors and a mechanism for the inhibition of mild steel corrosion with sodium propionate is proposed.
Doctor of Philosophy (PhD)
APA, Harvard, Vancouver, ISO, and other styles
11

Tavassoli-Salardini, Fereshteh. "Inhibition of mild steel corrosion in aqueous media with sodium propionate /." View thesis, 1996. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030901.133617/index.html.

Full text
APA, Harvard, Vancouver, ISO, and other styles
12

Mörtelmaier, Christoph [Verfasser], and J. [Akademischer Betreuer] Winter. "Propionate-Oxidizing bacteria in Anaerobic Biowaste Digesters / Christoph Mörtelmaier. Betreuer: J. Winter." Karlsruhe : KIT-Bibliothek, 2015. http://d-nb.info/1073204960/34.

Full text
APA, Harvard, Vancouver, ISO, and other styles
13

Hasegawa, Yoshinori, Kazuyoshi Imaizumi, Masashi Kondo, Mitsuo Sato, Naozumi Hashimoto, Satoru Ito, Tadakatsu Matsuno, et al. "Nongenomic Effects of Fluticasone Propionate and Budesonide on Human Airway Anion Secretion." Thesis, American thoracic society, 2012. http://hdl.handle.net/2237/18885.

Full text
APA, Harvard, Vancouver, ISO, and other styles
14

Jin, Zuwei. "Continuous extractive fermentation using hollow-fiber membrane extractors for enhanced propionate production /." The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487946103569259.

Full text
APA, Harvard, Vancouver, ISO, and other styles
15

Rouse, Jennifer. "Hyaluronic acid - Flucitasone Propionate : a novel formulation for sustained activity in the lung." Thesis, University of Strathclyde, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423861.

Full text
APA, Harvard, Vancouver, ISO, and other styles
16

Wilson, Kirkland A. Wilson. "Interrelations Between 3-Hydroxypropionate, Propionate, And ß-Alanine Metabolism: Relevance To Propionic Acidemia." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1515518969675728.

Full text
APA, Harvard, Vancouver, ISO, and other styles
17

Wa, Kasongo Kasongo. "Development and in vitro evaluation of a clobetasol 17-propionate topical cream formulation." Thesis, Rhodes University, 2007. http://hdl.handle.net/10962/d1003277.

Full text
Abstract:
One of the primary contributing factors to the escalating costs of health care is the high cost of innovator pharmaceutical products. As a consequence, health authorities in various countries and in particular in the developing world have identified generic prescribing and generic substitution as possible strategies to contain the escalating costs of health care provision. There is therefore a need for formulation scientists in developing countries to invest more time in the research and development of generic formulations. Clobetasol 17-propionate (CP) generic cream formulations containing 0.05% w/w of the drug were manufactured and characterized using in vitro testing. Formulation development studies were preceded by the development and validation of an RP-HPLC with UV detection for the quantitation and characterization of CP in innovator and generic cream formulations during formulation development and assessment studies. Furthermore the in vitro release ates of CP release from innovator and generic cream formulations were monitored using a validated in vitro release test method developed in these studies. The formulation of CP cream products was accomplished using a variety of commercially available mixed primary emulsifiers, such as Estol® 1474, Ritapro® 200, Emulcire® 61 WL and Gelot® 64. Successful formulations were selected based on their ability to remain physically stable immediately after manufacture and for 24 hours after storage at room temperature (22°C). Estol® 1474 was found to produce an unstable cream and was therefore not investigated further. The other three emulgents produced stable creams, but only the in vitro release profile of CP from a cream manufactured to contain Gelot® 64 was found to be statistically similar to that of the innovator formulation. Therefore the cream containing Gelot® 64 was selected as the most appropriate prototype generic cream formulation and was characterized in vitro in terms of CP content, viscosity, pH and in vitro release rate. Data generated from these studies were compared to those of the innovator product, Dermovate® cream, using statistical methods. The CP content, pH and in vitro release rate data of the CP formulation were similar to those of the innovator product, however the intrinsic viscosity of Dermovate® cream was almost three (3) times greater than the intrinsic viscosity of the test formulation developed using Gelot® 64. The CP cream formulation developed in these studies was stored for 4 weeks at 40 ± 2°C and 25 ± 5% RH in an incubator and the formulation was found to be stable. A formulation has been developed and assessed and found to be suitable for use as a topical semi-solid dosage form for CP.
APA, Harvard, Vancouver, ISO, and other styles
18

Cintra, Ana Carolina Suzuki Dias. "Alfa-oxidação de propionato está envolvida na redução da produção de plástico biodegradável em Burkholderia sacchari?" Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/42/42132/tde-19092008-104933/.

Full text
Abstract:
Burkholderia sacchari é uma nova espécie bacteriana do solo brasileiro que tem a capacidade de crescer em sacarose e acumular grânulos intracelulares de poliésteres pertencentes à família dos polihidroxiaIcanoatos (PHA). Quando cultivado em sacarose, o homopolímero poli-3¬hidroxibutirato é acumulado por esta bactéria, que é usado como um plástico biodegradável e biocompatível. Quando sacarose e ácido propiônico são fornecidos como fontes de carbono, as células de B. sacchari acumulam o copolímero poli-3-hidroxibutirato-co-3-hidroxivalerato (P3HB-co-3HV). Entretanto, uma pequena porcentagem do ácido propiônico fornecido é convertido a unidades 3HV devido à eficientes vias catabólicas que convertem este substrato preferencialmente a biomassa, CO2 e água, reduzindo portanto a eficiência da produção do polímero. Ao menos duas vias do catabolismo de propionato foram previamente propostas em B. sacchari: a-oxidação e ciclo do 2-metilcitrato (2MCC), sendo somente a última confilmada no nível molecular. Mutantes UV, obtidos anteriormente, foram incapazes de crescer em propionato (prp) e também apresentaram fenótipo afetado no crescimento em intermediários da a-oxidação. No presente trabalho, após uma busca em bibliotecas genômicas de B. sacchari, uma delas construída também no presente trabalho, três diferentes fragmentos de DNA presentes nos clones AI, PI e P2 foram capazes de restaurar o fenótipo prp+ aos mutantes. Experimentos quantitativos revelaram que AI somente restaurou parcialmente a conversão de propionato a unidades 3HV aos mutantes. PI foi capaz de restaurar a capacidade de crescimento em propionato, e em outros intermediários da a-oxidação, a um dos mutantes. Um DNA de 1.2 Kb, subfragmento de PI, ainda capaz de complementar mutantes prp, foi subclonado e seqüenciado, demonstrando similaridade a seqüências de DNA codificadoras de reguladores transcricionais do tipo LysR de várias bactérias, incluindo espécies de Bllrkholderia. Regiões adjacentes a LysR em diferentes genomas de Burkholderia são anotados como codificadores de acil-CoA desidrogenases, ao lado de proposta acil-CoA transferases/carnitina desidrogenases e de uma permease do facilitador maior da superfamília MFS-l. Após confirmação das mesmas regiões adjacentes em B. sacchari e também a sua específica deleção, será possível provar a presença da via do catabolismo de propionato indicada neste trabalho.
Burkholderia sacchari is a new bacterial species from brazilian soil, able to grow in sucrose, accumulating intracellular granules of polyester belonging to the polyhydroxyalkanoate family (PHA). When cultivated on sucrose, the homopolymer poly-3-hydroxybutyrate is accumulated by this bacterium, which is used as biodegradable and biocompatible plastic. When sucrose and propionic acid are supplied as carbon sources, B. sacchari cells accumulate the copolymer poly-3-hydroxybutyrate-co-3-hydroxyvalerate (P3HB-co-3HV). However, a small percentage ofthe propionic acid supplied is converted to 3HV units, because efficient catabolic pathways convert this substrate preferentially to biomass, CO2 and water, thus reducing the efficiency of polymer production. At least two propionate catabolic pathways have been previously indicated in B. sacchari: a-oxidation and the 2-methylcitric acid (2MCC), the latter confirmed at molecular leveI. UV mutants previously obtained were unable to grow in propionate (prp) and also showed the phenotype affected concerning grow on intermediates of propionate a-oxidation. In the present work, after a screening in B. sacchari genomic libraries, one ofthem constructed also in the present work, the prp + phenotype was restored to the mutants by three different DNA fragments harbored by dones A), PI and P2. Quantitative experiments revealed that AI restored only partially the quantitative conversion of propionate to 3HV units to the mutants. PI restored the ability to grow in propionate and in other intermediates of a-oxidation to one prp mutant. A DNA 1.2 Kb subfragment of PI, still able to complement prp mutants, was subcloned and sequenced, showing similarity to DNA sequences encoding to LysR-type transcriptional regulators of various bacteria, including BlIrkholderia species. Adjacent regions to LysR in different genomes of BlIrkholderia are annotated as encoding to acyl-CoA dehydrogenases, neighboring a predicted acyl-CoA transferases/carnitine dehydratase and a permease ofthe major facilitator superfamily MFS-1. After confirmation ofthe same adjacent regions in B. sacchari and also their especific deletion, it will be possible to prove the presence of the pathway indicated here in the catabolism of propionate.
APA, Harvard, Vancouver, ISO, and other styles
19

Jones, Robert Eric. "Effect of feeding calcium propionate on carcass composition, and productive performance of male broilers." Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=778.

Full text
Abstract:
Thesis (M.S.)--West Virginia University, 1999.
Title from document title page. Document formatted into pages; contains viii, 69 p. : ill. (some col.) Vita. Includes abstract. Includes bibliographical references (p. 58-62).
APA, Harvard, Vancouver, ISO, and other styles
20

Van, Bibber-Krueger Cadra. "Mineral supplementation of feedlot cattle." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/32646.

Full text
Abstract:
Doctor of Philosophy
Department of Animal Sciences and Industry
James S. Drouillard
Four studies evaluated effects of mineral supplementation on feedlot performance, carcass characteristics and ruminal fermentation of finishing cattle. Study 1 supplemented 0 or 3.3 g/d yeast combined with Cr propionate to steers separated into light and heavy groups. No treatment x weight group interactions were observed for ADG, DMI, final BW, carcass traits, or plasma glucose of lactate concentrations (P ≥ 0.06). A treatment x weight group interaction was observed for G:F (P = 0.03). In study 2, steers were supplemented 60 or 300 mg Zn/kg DM with or without zilpaterol hydrochloride (ZH). No interactions or effects of Zn or ZH were observed for IGF-1, plasma glucose, or lactate concentrations (P > 0.05). Plasma urea nitrogen (PUN) concentration decreased with ZH (P < 0.01). No interactions or effects of Zn or ZH were detected for ADG, DMI, final BW, G:F, and carcass traits were minimally affected (P ≥ 0.05). Study 3 evaluated effects of supplementing 30 or 100 mg Zn/kg DM (30 or 100Zn) with and without ractopamine hydrochloride (RH; 200 mg/d). No interactions or effects of Zn were observed for feedlot performance or PUN (P ≥ 0.07). Final BW, ADG, and HCW increased when heifers were fed RH (P ≤ 0.02). Zinc x RH interactions were observed for LM area and yield grade (P ≤ 0.01), but other carcass traits were not affected (P ≥ 0.08). In study 4, heifers were supplemented 0, 30, 60, or 90 mg Zn/kg DM. Zinc supplementation did not affect final BW, ADG, or DMI (P ≥ 0.07), but G:F increased linearly (P = 0.02). Carcass traits were not affected by Zn supplementation (P ≥ 0.07). Effects of in vitro Zn titration (0, 30, 60, 60, 90, 120, or 150 mg/kg Zn) were evaluated using ground corn and soybean meal as substrate. In vitro fermentation was not affected by added Zn (P ≥ 0.05). These studies suggest Cr and Zn supplementation minimally affected carcass traits, but Zn supplementation up to 60 mg/kg improved feed efficiency with minimal impact on ruminal fermentation. Supplementing increased Zn concentrations may alter fat and muscle deposition when fed with RH.
APA, Harvard, Vancouver, ISO, and other styles
21

Ferret, Haidy. "Obtention de motifs desoxy-polypropionate application à la synthèse de composés biologiquement actifs." Paris 6, 2009. http://www.theses.fr/2009PA066168.

Full text
Abstract:
Durant ma thèse, je me suis intéressée à la synthèse du myxovirescine A2, possédant des propriétés antibiotiques, et du (–)-doliculide, possédant des propriétés antitumorales. Le myxovirescine A2 est un macrocycle naturel à 28 chaînons produit par la bactérie Myxococcus. La synthèse des quatres fragments permettant d’accéder à ce composé a pu être réalisée en contrôlant de tous les centres stéréogènes présents dans ces fragments. . La synthèse du: fragment (C19–C28) a pu être réalisée en utilisant comme réaction clef une réaction d’alkylation de Myers suivie d’une réaction de Julia et d’une réduction, fragment (C15–C18) a été effectuée par alkylation de type Evans de l’oxazolidinone , fragment (C2–C3) a été synthétisé par nitrosation de la L-norvaline, fragment (C5–C14) a été envisagé par réarrangement énantiosélectif d’aminoalcool. Pour relier les fragments C15–C18 et C19–C28 du myxovirescine A2, une réaction de métathèse croisée a été réalisée. D’autre part, je me suis également intéressée à la synthèse formelle du fragment C1–C9 du (–)-doliculide, un dipeptide cyclique présent chez le lièvre de mer la Dolabella auricularia. Contrairement aux synthèses linéaires précédentes publiées dans la littérature, nous avons envisagé une voie convergente en réalisant aldolisation stéréosélective entre l’éthylcétone C1–C6 et l’aldéhyde C7–C9. L’aldéhyde C7–C9 a été obtenu grâce à l’utilisation d’une allylboration de type Roush. Une réaction d’alkylation Myers a permis de synthétiser l’éthylcétone et de contrôler les centres en C2 et C4. Si la condensation aldolique entre les fragment C1-C6 et C7-C9 a bien eut lieu, des problèmes de désoxygénation ont été rencontrés
APA, Harvard, Vancouver, ISO, and other styles
22

Harris, Hannah Charlotte. "An investigation into the properties of non-digestible carbohydrates that selectively promote colonic propionate production." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7623/.

Full text
Abstract:
Short chain fatty acids (SCFA), including propionate, are produced by the bacterial fermentation of carbohydrates in the colon. Propionate has many potential roles in health, including inhibiting cholesterol synthesis, de novo lipogenesis and increasing satiety. The profile of SCFA produced is determined by both the substrate available and the bacteria present and may be influenced by environmental conditions within the lumen of the colon. Whilst it may be beneficial to increase colonic propionate production, dietary strategies to achieve this are unproven. Adding propionate to food leads to poorer organoleptic properties, and oral propionate is absorbed in the small intestine. The optimum way to selectively increase colonic propionate would be to select fermentable carbohydrates that selectively promote propionate production. To date, few studies have undertaken a systematic assessment of the factors leading to increased colonic propionate production making the selection of propiogenic carbohydrates challenging. The aim of this thesis was to identify the best carbohydrates for selectively increasing propionate production, and to explore the factors which control propionate production. This work started with a systematic review of the literature for evidence of candidate carbohydrates, which led to a screen of ‘propiogenic’ substrates using in vitro batch fermentations and mechanistic analysis of the impact of pH, bond linkage and orientation using a range of sugars, polysaccharides and fibre sources. A new unit for SCFA production was developed to allow comparison of results from in vitro studies encompassing a range different methodologies found in the literature. The systematic review found that rhamnose yielded the highest rate and proportion of propionate production whereas, for polysaccharides, β-glucan ranked highest for rate and guar gum ranked highest for molar production, but this was not replicated across all studies. Thus, no single NDC was established as highly propiogenic. Some substrates appeared more propiogenic than others and when these were screened in vitro. Laminarin, and other β-glucans ranked highest for propionate production. Legume fibre and mycoprotein fibre were also propiogenic. A full complement of glucose disaccharides were tested to examine the role glycosidic bond orientation and position on propionate production. Of the glucose disaccharides tested, β(1-4) bonding was associated with increased proportion of propionate and α(1-1) and β(1-4) increased the rate and proportion of butyrate production. In conclusion, it appears that for fibre to affect satiety, high intakes of fibre are needed, and which a major mechanism is thought to occur via propionate. Within this thesis it was identified that rather than selecting specific fibres, increasing overall intakes of highly fermentable carbohydrates is as effective at increasing propionate production. Selecting carbohydrates with beta-bonding, particularly laminarin and other β(1-4) fermentable carbohydrates leads to marginal increases in propionate production. Compared with targeted delivery of propionate to the colon, fermentable carbohydrates examined in this thesis have lesser and variable effects on propionate production. A more complete understanding of the impact of bond configurations in polysaccharides, rather than disaccharides, may help selection or design of dietary carbohydrates which selectively promote colonic propionate production substrates for inclusion in functional foods. Overall this study has concluded that few substrates are selectively propiogenic and the evidence suggests that similar changes in propionate production may be achieved by modest changes in dietary fibre intake.
APA, Harvard, Vancouver, ISO, and other styles
23

Mbanya, J. N. "Effects of ruminal administration of acetate, propionate and distension on forage intake by dairy cows." Thesis, University of Leeds, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383900.

Full text
APA, Harvard, Vancouver, ISO, and other styles
24

Rinehart, Erica Marie. "The Effects of Short Chain Fatty Acids and Oxygen Levels on Listeria Monocytogenes Pathogenesis." University of Dayton / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1588239009629426.

Full text
APA, Harvard, Vancouver, ISO, and other styles
25

Burgess, Philippa. "Identification and characterisation of genes involved in the propionate and cholestrol catabolic pathways in Rhodococcus equi." Thesis, Royal Veterinary College (University of London), 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.669188.

Full text
APA, Harvard, Vancouver, ISO, and other styles
26

Hu, Dingfei. "Environmental fate and chemistry of a veterinary antibiotic-tylosin and monoterpenoid pesticides-thymol and phenethyl propionate." [Ames, Iowa : Iowa State University], 2007.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
27

Becker, Ulrike. "Smart Surfaces in Biobased Materials." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/30714.

Full text
Abstract:
The self-assembly blends of cellulose propionate (CP) and fluorine (F)-containing cellulose derivatives was examined on a model system of solvent cast films. The F-containing derivatives were either high molecular weight statistical cellulose esters with a number of F-containing substituent evenly distributed along the backbone (F-esters), or F-terminated CP-segments with exactly one F-containing endgroup. The F-esters were synthesized in a homogeneous phase and identified by 19F-NMR. Thermal analysis showed improved thermal stability of the F-esters when compared to F-free derivatives. 1-monohydroxy functionalized CP-segments were synthesized by HBr depolymerization using either a commercially available CP with residual OH-groups or a perpropionylated CP (CTP). The hydrolysis using the commercial CP yielded only segments of a minimum DP of 50 and the Mark-Houwink constant declined from 1 to 0.6. The results indicate that in the presence of free hydroxyls branches are formed by transglycosidation. The hydrolysis from perpropionylated CP resulted in segments with a minimum DP of 7, which is in accordance to previous studies. F-terminated CP segments were synthesized by coupling of the appropriate F-containing alcohol to the CP segment via toluene diisocyanate. Solutions containing F-terminated CP-segments showed typical critical micelle behavior. The critical micelle concentration depended on the molecular weight of the CP segment and the type of F-containing endgroup. The micelles are thought to consist of a core of the F-endgroups and a corona made-up of CP. Films containing the oligomers cast from micellar solution revealed a linear decrease in wetting force according to the blend composition of the oligomer, i.e. behavior according to the rule of mixing. This indicated the absence of surface segregation of the F-endgroup and it is explained with the fact that the micellar structure is retained in the solid state, suppressing surface segregation. The solid state micelles were visualized as dome-like protrusions by height image atomic force microscopy. In systems blended with CP the distance between the protrusions was found to increase with increasing CP content which was explained by a dilution process. Films containing F-esters were characterized by wetting force measurements and x-ray photoelectron spectroscopy (XPS). The wetting force decreased dramatically at low blend content of the F-ester and at the same time an F surface-concentration higher then expected from the blend composition was found by XPS. This indicated self-assembly by surface segregation of the F-containing species during film formation. The extent of surface segregation was found to depend on the type of the F-ester group as well as on the blend concentration of the F-ester. Dynamic wetting force measurements revealed hysteresis in films containing either F-esters or F-terminated CP segments. The hysteresis was found to be both kinetic (water sorption and reorganization) and thermodynamic (surface roughness and surface coverage with F-moieties) in nature. Consecutive force loops revealed an increase in the wetting force (advancing and receding) with increasing loop number, indicating the increased hydrophobicity of the surface. The force increase was determined to be due to water sorption as well as due to surface reorganization. An increase in the size of the F-groups signified a decrease in reorganization rate due to a decreased mobility of the group. The process of reorganization was fully reversible, a behavior which is congruent with the definition of smart behavior.
Ph. D.
APA, Harvard, Vancouver, ISO, and other styles
28

Malapit, Monica, and Evan Mallory. "In vitro aerodynamic analysis of co-spray dried fluticasone propionate (FP) and salmeterol xinafoate (SX) dry powder inhalation aerosols with lactose-alternative excipient." The University of Arizona, 2017. http://hdl.handle.net/10150/624206.

Full text
Abstract:
Class of 2017 Abstract
Objectives: Milk protein allergy is estimated to affect 1.2% to as much as 17% of people of all ages. Advair® Diskus® (FP/SX) utilizes lactose as an excipient which limits the utility of this product for this population. Furthermore, Advair® Diskus® is formulated as an interactive physical mixture via a micronization process. Alternatively, spray dried engineering achieves narrow particle size distribution, allowing greater deposition in the targeted respiratory bronchioles. The purpose of this dry powder inhaler (DPI) study was to conduct an in vitro comparative analysis of the aerodynamic performance of a co-spray dried lactose-free formulation of FP/SX with a mannitol excipient as a molecular mixture versus the Advair® Diskus® 250/50 (FP/SX) interactive physical mixture product. Methods: Utilizing mannitol as an excipient, a co-spray dried FP/SX powder was prepared using the Buchi Mini-Spray Dryer B-290 under closed system configuration. The resulting feed solution was spray dried at pump rates of 25%, 50%, and 100% with all other parameters remaining constant (aspiration, atomization rate, nitrogen gas rate). The primary outcome measure, aerodynamic performance, was assessed using the Copley Next-Generation Impactor (NGI). NGI data for the DPIs was used to calculate mass median aerodynamic diameter (MMAD), geometric standard deviation (GSD), and fine particle fraction (FPF) of each powder, including the Advair® Diskus®. Residual water content was quantified by Karl Fischer titration. Particle characteristics were visualized by scanning electron microscopy. Results: FPF, MMAD, and GSD were calculated from NGI data; Wolfram Alpha software was used to calculate MMAD and GSD. T-test regression was used for comparative analysis of spray-dried and Advair® Diskus® powders. MMAD for each spray dried sample was analyzed using a t-test regression against the MMAD values from the Advair® Diskus®. Using aerodynamic analysis studies triplicated for each powder, there was no significant difference between the spray dried powder and Advair® Diskus® for MMAD and GSD (p-values >0.05). The 50% and 100% pump rate samples had similar FPF to the Advair® Diskus® (p-values >0.05). However, the 25% pump rate sample had a significantly improved FPF compared to the Advair® Diskus® (p <0.01). Conclusions: A co-spray-dried lactose-free formulation of FP/SX with a mannitol excipient demonstrated similar aerodynamic performance to the Advair® Diskus® which consists of a physical mixture of two drugs with lactose. Of significance, 25% pump rate spray-dry conditions demonstrated an improved FPF compared to the Advair® Diskus®.
APA, Harvard, Vancouver, ISO, and other styles
29

Simmons, H. A. "The measurement of propionate production in the caecum and colon of the pony and its conversion to glucose." Thesis, University of Liverpool, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372704.

Full text
APA, Harvard, Vancouver, ISO, and other styles
30

Sangoi, Maximiliano da Silva. "DESENVOLVIMENTO E VALIDAÇÃO DE METODOLOGIA PARA AVALIAÇÃO DE FLUTICASONA POR CROMATOGRAFIA LÍQUIDA E ELETROFORESE CAPILAR." Universidade Federal de Santa Maria, 2009. http://repositorio.ufsm.br/handle/1/5886.

Full text
Abstract:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Fluticasone propionate (FP) is a synthetic glucocorticoid with potent anti-inflammatory activity that has been effectively used for the treatment of seasonal and allergic perennial rhinitis, minimizing systemic activity. In the present study, the methods were developed and validaded for assessment of FP in pharmaceutical products. The analysis by reversed-phase liquid chromatography were performed using Shim-pack CLC-ODS column (150 x 4.6 mm), maintained at 35 °C. The mobile phase was consisted of acetonitrile/ methanol/ 0.01M phosphate buffer pH 4 (35:35:30), run at flow rate of 1 mL/min and using photodiode array detection at 240 nm. The chromatographic separation was obtained within 8 minutes and it was linear in the concentration range of 0.05-150 μg/mL (r2 = 0,9999). The method was successfully applied for the determination of FP in creams and nasal sprays pharmaceutical formulations. The micellar electrokinetic chromatography was also developed and validaded. The analyses were performed on a fused-silica capillary (50 μm i.d.; effective length, 40 cm) and background electrolyte consisted of 25 mM borate and 25mM SDS solution at pH 9. The capillary temperature was maintained at 35 °C and the applied voltage was 20 kV. The injection was performed using the hydrodynamic mode at 50 mbar for 6 s, with detection at 238 nm. The electrophoretic separation was obtained with migration time of 5.6 and 5.1 minutes for the FP and prednisolone acetate (internal standard), respectively, and with run time of 7 minutes. The method was linear in the concentration range of 2-80 μg/mL (r2 = 0.9956). The procedures were validated evaluating parameters such as the specificity, linearity, precision, accuracy, and robustness, limit of detection and limit of quantitation, whose results have met the requirements recommended. The proposed methods were used for the analysis of pharmaceutical products, demonstrating nonsignificative difference of the results (P > 0.05). Then, the procedures contribute to improve the quality control, assuring the safety and therapeutic efficacy of pharmaceutical formulations.
O propionato de fluticasona (PF) é um glicocorticóide sintético com potente atividade antiinflamatória utilizado efetivamente no tratamento de rinites alérgicas sazonais e perenes, minimizando a atividade sistêmica. No presente trabalho foram desenvolvidos e validados métodos para avaliação de PF em produtos farmacêuticos. As análises por cromatografia líquida em fase reversa foram realizadas utilizando coluna Shim-pack CLC-ODS (150 x 4,6 mm), mantida à 35ºC. A fase móvel foi composta de acetonitrila/ metanol/ tampão fosfato 0,01M pH 4 (35:35:30), eluída na vazão de 1 mL/min e detecção no ultravioleta a 240 nm. A separação cromatográfica foi obtida no tempo de 8 minutos, sendo linear na faixa de concentração de 0,05-150 μg/mL (r2 = 0,9999). O método foi aplicado para análise de PF em cremes e sprays nasais. Paralelamente, desenvolveu-se e validou-se método por cromatografia eletrocinética micelar. Executaram-se as análises utilizando capilar de sílica (comprimento efetivo de 40 cm e diâmetro de 50 μm) e solução eletrolítica composta de borato 25 mM e SDS 25 mM, pH 9. O capilar foi mantido a temperatura de 35ºC, e aplicada voltagem de 20 kV. O tempo de injeção foi de 6 s com pressão de 50 mbar e detecção no UV a 238 nm. Realizou-se a separação eletroforética com tempo de migração de 5,6 e 5,1 minutos para o PF e acetato de prednisolona (padrão interno), respectivamente, com tempo de corrida de 7 minutos. O método foi linear na faixa de 2-80 μg/mL (r2 = 0,9956). Os procedimentos foram validados, avaliando-se os parâmetros de especificidade, linearidade, precisão, exatidão, robustez, limite de detecção e quantificação, cujos resultados cumpriram os requisitos preconizados. Os métodos propostos foram utilizados para análise de produtos farmacêuticos, demonstrando que não há diferenças significativas dos resultados (P > 0,05). Assim, os procedimentos pesquisados contribuem para aprimorar o controle da qualidade, garantindo a segurança e eficácia terapêutica das formulações farmacêuticas.
APA, Harvard, Vancouver, ISO, and other styles
31

Dantas, Patrícia Allue. "Géis superabsorventes de propionato acetato de celulose e acetato de celulose: síntese, caracterização e liberação controlada de pesticida." Universidade Federal de São Carlos, 2011. https://repositorio.ufscar.br/handle/ufscar/1166.

Full text
Abstract:
Made available in DSpace on 2016-06-02T19:19:54Z (GMT). No. of bitstreams: 1 DANTAS_Patricia_2011.pdf: 2256820 bytes, checksum: e36b1fbb6b7a53c4ba196910208d1dd3 (MD5) Previous issue date: 2011-12-16
Financiadora de Estudos e Projetos
Hydrogels derived from cellulose acetate propionate (CAP) and cellulose acetate (CA) were synthesized with the cross-linking agents PMDA (Pyromellitic Dianhydride) and BTDA (Dianhydride 3, 3 ', 4, 4' Benzophenone Tetracarboxylated) with 3:1 stoichiometry in relation to the mass of the crosslinker agent x mass of available hydroxyls in the polymer chain. The gels were obtained in the form of films and particles, the raw materials were characterized with Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), Spectroscopy in Region of Fourier Transform Infrared (FTIR) and in relation to the degree of substitution (GS). The gels synthesized were characterized using FTIR techniques in order to show the esterification, TGA and DSC to perform comparative analysis and study of thermal properties between the CAP and CA reagents and gels, and Scanning Electron Microscopy (SEM) were used for observation of the gels synthesized and the geometry of the particles obtained, the porosity of observation and observation of surface changes, was performed to determine the crosslinking density of the second theory of Flory Rehner, study the density of the gels, and degree of swelling of the study best solvent for swelling of the gels. Gels derived from CAP were tested in the adsorption studies and controlled release of the herbicide paraquat. For the phenomenon of controlled release, we studied the phenomena of transport and release curves. The release profiles were studied by using the mathematical model published by Korsmeyer-Peppas and the mainly results has showed that model was appropriated for process data analysis of controlled release in long periods.
Hidrogéis derivados de Propionato Acetato de Celulose (CAP) e Acetato de Celulose (CA) foram sintetizados com os agentes reticuladores PMDA (Dianidrido Piromelítico) e BTDA (Dianidrido 3, 3´, 4, 4´ Benzofenona Tetracarboxílico), com estequiometrias 3:1 em relação à massa do agente reticulador x massa de hidroxilas disponíveis na cadeia polimérica, com obtenção de géis em formato de filmes e particulados; as matérias-primas foram caracterizadas com Análise Termogravimétrica (TGA), Calorimetria Diferencial de Varredura (DSC), Espectroscopia na Região do Infravermelho com Transformada de Fourier (FTIR) e em relação ao Grau de Substituição (GS). Os géis sintetizados foram caracterizados utilizando as técnicas de FTIR, para evidenciação da esterificação; TGA e DSC para realização de análise comparativa e estudo das propriedades térmicas entre os reagentes CAP e CA e os géis obtidos; e Microscopia Eletrônica de Varredura (MEV), utilizada para observação dos géis sintetizados em relação à geometria das partículas obtidas, observação da porosidade e observação de alterações superficiais; foi realizada a determinação da densidade de ligações cruzadas segundo a Teoria de Flory Rehner; estudo da densidade dos géis, que variaram de 0,4 a 1,51 g/cm3; grau de inchamento que obteve variações entre os diferentes géis de 6,53 à 11,8; e o estudo do melhor solvente para intumescimento dos géis. Nos géis derivados de CAP, foram realizados ensaios de adsorção e liberação controlada do herbicida Paraquat. Para o fenômeno de liberação controlada, foram estudados os fenômenos de transporte e as curvas de liberação; os perfis de liberação foram estudados pelo modelo matemático de Korsmeyer-Peppas; e apresentaram como o gel com maior porcentagem de adsorção e melhor potencial para liberação controlada por longos períodos o gel CAP 3B1.
APA, Harvard, Vancouver, ISO, and other styles
32

Trakas, Kostas. "A cost-effectiveness assessment of fluticasone propionate, budesonide, and beclomethasone dipropionate for the treatment of moderate to severe asthma." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ29333.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
33

Toong, Samuel Y. "Modulation of Ã-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptors by a novel organic nitrate ester." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0003/MQ45556.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
34

Fauzee, Ayeshah Fateemah Beebee. "Establishing a formulation design space for a generic clobetasol 17- propionate cream using the principles of quality by design." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/5868.

Full text
Abstract:
The pharmaceutical industry is global, is highly regulated and is able to achieve reasonable product quality but at high cost with maximum effort. Numerous challenges face the pharmaceutical industry and include a shrinking research pipeline, less innovation, outsourcing, investments, increasing research and development costs, long approval times, growth of the generic industry, failure to understand or analyze manufacturing failure and wastage as high at fifty percent for some pharmaceutical products. An efficient and flexible pharmaceutical sector should be able to consistently produce high quality pharmaceutical products at a reduced cost with minimal waste. As a result, Food and Drug Administration (FDA) and other agencies such as the International Conference on Harmonization (ICH) have embraced a “Quality by Design” (QbD) paradigm and this has become the “desired state” so as to shift manufacturing from being empirical to a science, engineering, and risk based approach. QbD is a systematic approach for the development of high quality pharmaceutical dosage forms that begins with predefined objectives based on the premise that quality must be built into and not tested into a product. QbD together with the establishment of a design space for dosage forms is a fairly new concept and there is limited published data on QbD concepts that report the entire process of identifying Critical Quality Attributes (CQA), design of a formulation and manufacturing process to meet product CQA, understanding the impact of material attributes and process parameters on product CQA, identification and controlling sources of variability in materials and processes that affect the CQA of a product and finally establishing, evaluating and testing a design space using both in vitro and in vivo approaches to assure that a product of consistent quality can always be produced. The objective of these studies was to implement a QbD approach to establish a design space for the development and manufacture of a safe, effective, stable generic formulation containing 0.05% w/w clobetasol 17-propionate (CP) that had similar in vitro and in vivo characteristics to an innovator product, Dermovate® (Sekpharma® Pty Ltd, Sandton, Gauteng, RSA). Such a product would pose a minimal risk of failure when treating severe skin disorders such as seborrhoeic dermatitis, extreme photodermatitis and/or severe psoriasis in HIV/AIDS patients in Southern Africa.
APA, Harvard, Vancouver, ISO, and other styles
35

Andrade, Diego Fontana de. "Nanocápsulas de núcleo lipídico : estudos de penetração cutânea e proposição de estratégias para a avaliação da liberação in vitro." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/94616.

Full text
Abstract:
Neste trabalho foi avaliada a permeação/penetração cutânea in vitro (pele suína) de propionato de clobetasol nanoencapsulado incorporado em um semissólido, empregando células de difusão de Franz. A nanoencapsulação foi capaz de reduzir a quantidade de fármaco que penetra nas camadas da pele (estrato córneo, epiderme e derme) sem alterar a forma (distribuição percentual) como o propionato de clobetasol se distribui. A adequabilidade de diferentes membranas sintéticas (acetato de celulose, policarbonato e membrana de diálise) para a avaliação da liberação in vitro, empregando células de difusão de Franz, a partir desta formulação foi também estudada. A partir da combinação de diferentes técnicas analíticas (espalhamento de luz dinâmica, microscopias eletrônicas de transmissão e varredura) foi observado que a membrana de menor tamanho de poro (membrana de diálise, 12 kDa de cut off) é a mais adequada para a condução deste tipo de avaliação, pois é a única capaz de evitar a passagem de nanocápsulas íntegras da formulação para o meio receptor das células de difusão, em detrimento das membranas de policarbonato e acetato de celulose (0,05 μm e 0,45 μm de tamanho de poro, respectivamente). Além disso, uma nova estratégia para a avaliação da liberação in vitro de fármacos associados a nanocápsulas de núcleo lipídico, combinando fluxo contínuo de meio de liberação e sacos de diálise foi proposta neste trabalho. A técnica mostrou-se adequada para a obtenção do perfil de liberação in vitro a partir de suspensões de nanocápsulas contendo diferentes fármacos modelo (prednisolona e propionato de clobetasol), possibilitando a diferenciação destes sistemas de soluções contendo os fármacos livres, graficamente e pelos valores de fluxo calculados. Adicionalmente, esta estratégia mostrou-se apropriada para a manutenção da concentração de fármaco no meio de liberação afastada da saturação, contribuindo para o atendimento da condição sink. Ainda, classificamos o sistema como um protótipo semi-automatizado para a avaliação da liberação in vitro de fármacos, capaz de gerar resultados com maior precisão em relação à diálise convencional.
The in vitro cutaneous permeation/penetration (porcine skin) of clobetasol propionate-loaded lipid-core nanocapsules incorporated into a semisolid dosage form was evaluated, using the Franz diffusion cells technique. It was shown that the nanoencapsulation was able to reduce the drug amount penetration into skin layers (stratum corneum, epidermis and dermis) without changing the way (percentual distribution) that it was distributed. The suitability of different synthetic membranes (cellulose acetate, polycarbonate, and dialysis membrane) to assess the in vitro drug release using Franz diffusion cells from this formulation was also studied. It was ascertained by combining different analytical techniques (dynamic light scattering, scanning and transmition electron microscopy) that the membrane with smaller pore size (dialysis membrane, 12 kDa cut off) is the most appropriate for conducting this kind of study, because it is the only one able of preventing the passage of intact nanocapsules from formulation to Franz diffusion cells receptor media, instead of polycarbonate and cellulose acetate membranes (0.05 and 0.45 pore size, respectively). In addition, a new strategy to assess in vitro drug release drug-loaded lipid-core nanocapsules was proposed, associating continuous flow of release media and dialysis sac. The proposed system was adequate to assess the in vitro drug release profiles from nanocapsule suspensions containing different model drugs (prednisolone and clobetasol propionate), enabling the differentiation of these systems from drug solutions, graphically and by the calculated flux values. Furthermore, this strategy was suitable to maintain the drug concentration into release media far away from saturation, contributing to the sink condition. Also, the proposed system was described as a semi-automated prototype for in vitro drug release evaluation, able to produce results with greater accuracy than conventional dialysis technique.
APA, Harvard, Vancouver, ISO, and other styles
36

Alsugoor, Mahdi. "Regulation of induced nitric oxide synthase in vascular smooth muscle cells by glucocorticoids." Thesis, University of Hertfordshire, 2017. http://hdl.handle.net/2299/19617.

Full text
Abstract:
The upregulation of the inducible nitric oxide synthase (iNOS) and nitric oxide (NO) production have been implicated in inflammatory pathologies. Although research has revealed that glucocorticoids (GCs) such as dexamethasone and hydrocortisone inhibit iNOS expression and NO production, it remains unclear how these compounds attenuate iNOS expression and function. In response, this thesis has compared the effects of nonselective GCs (i.e., dexamethasone and hydrocortisone) with a selective GC namely, fluticasone propionate (fluticasone) to identify the precise GC actions that regulate the iNOS pathway. Additional investigations were performed to distinguish the GC and non-GC actions using receptor antagonists. Since the effects of GCs on upstream signalling pathways remain vague, further studies were conducted to investigate whether fluticasone regulates the p38 mitogen-activated protein kinases or protein kinase B (Akt) pathways, both of which have been reported to be critical for the induction of iNOS. All experiments were conducted using primary cultures of rat aortic smooth muscle cells (RASMCs). The cells were activated with bacterial LPS (100 μg/mL) and interferon-gamma (IFN-γ, 100 U/mL) to induce iNOS and NO. Nitrite levels in cellular supernatants were quantified by the Griess assay, and expressions of iNOS, phospho-p38 (P-p38), and phospho-Akt (P-Akt) were investigated by western blotting. Dexamethasone (0.1-10.0 μM) inhibited iNOS expression and NO production in a concentration dependent manner that was significant at higher concentrations (0.3-10.0 μM). Hydrocortisone (0.01-10.0 μM) also inhibited iNOS expression and NO production in a concentration dependent manner which was significant at the higher concentrations (0.1-10.0 μM). By contrast, fluticasone (0.1 nM-3.0 μM) inhibited NO production and iNOS expression only partially (~50%), and the effects were significant at 1 nM-3 μM. RU-486 (10 μM), a GC receptor (GCR) blocker, was able to reverse the inhibitions caused by dexamethasone, hydrocortisone, and fluticasone, though eplerenone (0.1-10.0 μM), the mineralocortocoid receptor blocker, had no effect. Fluticasone also inhibited the phosphorylation of p38 and Akt in activated RASMCs. The inhibitions were reversed upon incubation with RU-486 (10 μM) for 1 h prior to the addition of fluticasone. The partial inhibition of iNOS and NO by fluticasone suggests that the actions of dexamethasone and hydrocortisone were not restricted solely to GCR and that other receptors or pathways, if not both, might regulate iNOS and NO in RASMCs. In conclusion, the nonselective GCs (i.e., dexamethasone and hydrocortisone) showed a full inhibition of iNOS expression and function, whereas fluticasone only partially inhibited both processes. The inhibitions were reversed by RU-486, but not eplerenone, which strongly suggests a GC-mediated response to all three compounds investigated. Regarding fluticasone, mechanistic studies revealed that the GC can regulate key signalling pathways associated with the induction of iNOS. More specifically, fluticasone reduced the phosphorylation of p38 and Akt, thereby suggesting that its actions can be mediated by suppressing these kinase pathways, which are widely reported to critically regulate iNOS expression and function.
APA, Harvard, Vancouver, ISO, and other styles
37

Graybill, Eric R. "EXAMINATION OF MITOCHONDRIAL CIT3 IN SACCHAROMYCES CEREVISIAE AS THE GENE FOR METHYLCITRATE SYNTHASE." Miami University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=miami1157995234.

Full text
APA, Harvard, Vancouver, ISO, and other styles
38

Silva, Luis Antônio Dantas. "Penetração cutânea passiva e iontoforética de propionato de clobetasol incorporado em carreadores lipídicos nanoestruturados." Universidade Federal de Goiás, 2013. http://repositorio.bc.ufg.br/tede/handle/tde/3009.

Full text
Abstract:
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2014-09-04T17:22:48Z No. of bitstreams: 2 Luis Antonio - Dissertação mestrado - versão biblioteca.pdf: 706561 bytes, checksum: ba004353ceb320d9ea4f9c0ef0b105bd (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5)
Made available in DSpace on 2014-09-04T17:22:48Z (GMT). No. of bitstreams: 2 Luis Antonio - Dissertação mestrado - versão biblioteca.pdf: 706561 bytes, checksum: ba004353ceb320d9ea4f9c0ef0b105bd (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-03-18
Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
Clobetasol propionate is one of the most potent topical corticosteroids usually available and has been established the use in treatment of various skin pathology. However its systemic absorption may cause serious side effects. The use of lipids nanocarriers and application of iontophoretic current shown potential to further controlled release of clobetasol propionate and increase their retention in the stratum corneum, thus making its management more effective and safe. In this study an analytical method was developed and validated for quantification of clobetasol propionate in nanocarriers and pig skin, used as model membranes in vitro permeation studies. Nanostructured lipid carriers (NLC) were obtained by dilution of microemulsion and chitosan-coated NLC (NLC-Ch) by the dripping of NLC in chitosan solution. The developed nanocarriers were characterized to mean diameter, polydispersity index, zeta potential, drug loading, recovery and encapsulation efficiency. The in vitro release and permeation profile of clobetasol free and nanoencapsulated was evaluated using Franz cells. The nanocariers obtained of 125 nm and uniform size distribution, whit PdI 0,25. The increase in size of NLC-Ch and the inverting the value of zeta potential, suggest that there was a coating of the CLN by chitosan, though interaction of charges. The NLC and NLC-Ch showed recovery values greater than 80% and encapsulation efficiency than 90%. The release profile of clobetasol from the developed formulations showed a controlled release with 35% in 24 hours of study. The nanoenapsulation of clobetasol in the NLC-Ch and NLC resulted in retention increased in the stratum corneum of 9.2 an 7.8 fold, respectively, compared to free drug. The retention of the clobetasol in the stratum corneum was 4 and 2 times higher when electric current was applied to the formulation CLNQ, compared to the free drug and encapsulated in NLC, respectively. The accumulation of the drug in the stratum corneum, promoted by lipid carriers, shows that these systems are effective for potential topical delivery to minimize the permeation of the drug into the bloodstream and reduces the side effects.
O propionato de clobetasol é um dos mais potentes corticosteroides tópicos disponíveis atualmente e tem uso consagrado no tratamento de diferentes patologias cutâneas. Contudo, a sua absorção sistêmica pode causar graves efeitos adversos. O uso de nanocarreadores lipídicos e a aplicação de corrente iontoforética apresentam potencial para promover liberação controlada do propionato de clobetasol e aumentar a sua retenção no estrato córneo, tornando assim sua administração mais segura e efetiva. No presente trabalho, um método cromatográfico foi desenvolvido e validado para quantificação do propionato de clobetasol nos nanocarreadores e na pele de porco, utilizada como modelo de membrana nos estudos de permeação in vitro. Carreadores lipídicos nanoestruturados (CLN) foram obtidos pelo método da diluição de microemulsão e CLN revestidos com quitosana (CLN-Q) foram obtidos pelo gotejamento dos CLN em solução de quitosana. Os nanocarreadores desenvolvidos foram caracterizados quanto ao diâmetro médio, índice de polidispersividade, potencial zeta, carga de fármaco, recuperação e eficiência de encapsulação. O perfil de liberação e de permeação in vitro do clobetasol livre e nanoencapsulado foi avaliado utilizando células de Franz. Os CLN obtidos apresentaram tamanho de 125 nm e distribuição de tamanho uniforme, com PdI de 0,25. O aumento no tamanho médio dos CLN-Q, para 257 nm, e a inversão no valor de potencial zeta sugerem que houve revestimento dos CLN pela quitosana, por meio de interação de cargas. Os CLN e CLN-Q apresentaram valores de recuperação maiores que 80% e de eficiência de encapsulação superiores a 90%. O perfil de liberação do clobetasol a partir das formulações desenvolvidas mostrou uma liberação controlada, com cerca de 35% em 24 horas de estudo. A nanoencapsulação do clobetasol nos CLN-Q e CLN resultou em retenção aumentada do fármaco no estrato córneo de 9,2 e 7,8 vezes, respectivamente, comparado ao fármaco livre. A retenção do clobetasol no estrato córneo foi de 4 e 2 vezes maior quando corrente elétrica foi aplicada na formulação CLNQ, comparado ao fármaco livre e encapsulado nos CLN, respectivamente. O acúmulo do fármaco no estrato córneo, promovido pelos carreadores lipídicos, mostrou que esses sistemas são efetivos para entrega tópica deste fármaco com potencial para minimizar sua absorção percutânea, e dessa forma, diminuir os seus efeitos adversos.
APA, Harvard, Vancouver, ISO, and other styles
39

Majdoub, Linda. "Orientation propionique du profil fermentaire ruminal : conséquences sur le métabolisme splanchnique des nutriments énergétiques et sur la fourniture et l'utilisation du glucose par le muscle chez l'agneau recevant du fourrage vert." Rennes, ENSA, 2002. http://www.theses.fr/2002NSARB142.

Full text
APA, Harvard, Vancouver, ISO, and other styles
40

Silva, Fernando Roberto Ferreira. "Efeitos dos esteroides anab?licos androg?nicos sobre fun??es cognitivas de ratos." Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17238.

Full text
Abstract:
Made available in DSpace on 2014-12-17T15:36:43Z (GMT). No. of bitstreams: 1 FernandoRFS_TESE.pdf: 469950 bytes, checksum: a8f86cc336421fd74e299ebe8f8d1daf (MD5) Previous issue date: 2014-11-04
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
The use and the demand for substances that enhance masculinity, strength and sexual power are not novel. Over the years, this search has assisted the research directions in this area, leading to the discovery of the primary male sex hormone testosterone in 1935. Since then, numerous testosterone analogue compounds were synthesized, which are generically called Anabolic Androgenic Steroids (AAS). The AAS were produced for therapeutic purposes, but an increase in the use of these compounds for other purposes occurred over time. Initially they were used mainly to improve performance in athletes. However, recent studies have shown that the use of AAS by non-athletes with aesthetical purposes have been increasing as well. The abuse of AAS with non-clinical purposes can promote a number of physiological alterations, such as heart, liver, respiratory and psychological problems such as changes in mood, levels of anxiety and aggression. Exposure to supraphysiological doses of AAS is associated with behavioral changes, however, little is known about the effects of AAS on cognitive functions. In this work, we aimed to mimic the AAS abuse in humans with intramuscular administration of a supraphysiological dose of testosterone propionate (TP) in rats. We investigated the effects of this treatment on different aspects of cognitive function, specifically learning, memory and anxiety. Adult male Wistar rats were tested in the spontaneous alternation, novel object recognition and plus-maze discriminative avoidance tasks. The control group received intramuscular injections of vegetable oil (vehicle), and the TP group received injections of TP (10 mg/kg, i.m.). The injections were administered for 40 days, with intervals of 48 hours (chronic treatment) or in a single injection (acute treatment). In addition to the behavioral assessments, we performed biochemical analyzes as indicators of the endocrine effects of the treatment. Our results show that chronic treatment with a supraphysiological dose of TP caused memory impairments in the novel object recognition and the discriminative avoidance tasks. The spatial working memory (evaluated by spontaneous alternation task) was not affected. Also, we did not observe changes in anxiety levels. Regarding the biochemical parameters, chronic treatment increased serum levels of glutamicpyruvic transaminase, an indicator of hepatic and pancreatic lesions (as those observed after chronic use of these substances in humans). On the other hand, acute treatment with PT did not promote significant changes in any of these parameters when compared to the control group. In summary, we conclude that chronic treatment with a supraphysiological dose of testosterone propionate produces memory deficits in novel object recognition and retrieval of the discriminative avoidance task in adult male rats
A utiliza??o e a busca por subst?ncias que aumentem a masculinidade, a for?a e a pot?ncia sexual n?o ? recente. Com o tempo, essa busca auxiliou no direcionamento de pesquisas na ?rea, levando a descoberta do principal horm?nio masculino a testosterona em meados da d?cada de 30. A partir desse momento, in?meros compostos foram sintetizados com o intuito de mimetizar os efeitos deste horm?nio, aos quais hoje chamamos genericamente de Esteroides Anab?licos Androg?nicos (EAA). A princ?pio, esses EAA foram sendo produzidos com prop?sitos terap?uticos. No entanto, iniciou-se o uso crescente desses compostos com outras finalidades, principalmente para a melhoria de desempenho em atletas. Al?m disso, estudos recentes t?m demonstrado que os EAA est?o sendo cada vez mais utilizados por n?o atletas, por indiv?duos que n?o s?o atletas, mas, buscam um corpo esteticamente perfeito. Paralelamente, o crescente abuso dos EAA com finalidades n?o cl?nicas pode promover uma s?rie de altera??es fisiol?gicas nocivas, tais como problemas card?acos, hep?ticos, respirat?rios e tamb?m psicol?gicos como altera??es de humor, nos n?veis de ansiedade e na agressividade. A exposi??o a doses suprafisiol?gicas de EAA est? associada com altera??es comportamentais, contudo, pouco se sabe sobre os efeitos dos EAAs sobre as fun??es cognitivas. Neste trabalho, mimetizamos o abuso de EAA em humanos atrav?s da administra??o intramuscular de uma dose suprafisiol?gica de propionato de testosterona (PT), em ratos, com o objetivo de investigar os efeitos desse tratamento sobre diferentes aspectos das fun??es cognitivas, especialmente aprendizado, mem?ria e ansiedade. Ratos Wistar machos adultos foram submetidos aos testes de alterna??o espont?nea, reconhecimento de objetos e esquiva discriminativa em labirinto em cruz elevado. O grupo controle recebeu inje??es intramusculares de ?leo vegetal (ve?culo); e o grupo testosterona recebeu inje??es de PT (10 mg/kg, i.m.). As inje??es foram administradas por 40 dias, com intervalos de 48 horas (tratamento cr?nico) ou em uma ?nica inje??o (tratamento agudo). Al?m das avalia??es comportamentais, foram realizadas an?lises bioqu?micas como indicadores dos efeitos end?crinos do tratamento. Nossos resultados mostram que o tratamento cr?nico com uma dose suprafisiol?gica de PT acarretou preju?zos na mem?ria de reconhecimento de objetos novos e na evoca??o da tarefa da esquiva discriminativa. A mem?ria espacial operacional (avaliada pelo teste de alterna??o espont?nea) n?o foi afetada bem como n?o observamos altera??es nos n?veis de ansiedade. Em rela??o aos par?metros bioqu?micos avaliados, o tratamento cr?nico elevou os n?veis s?ricos da transaminase glut?mica pir?vica (TGP), um indicador da presen?a de les?es hep?ticas e pancre?ticas (assim como as observadas ap?s o uso cr?nico dessas subst?ncias em humanos). Por outro lado, o tratamento agudo com PT n?o promoveu altera??o significativa em nenhum dos par?metros avaliados, quando comparados ao grupo controle. Em s?ntese, podemos concluir que o tratamento cr?nico com uma dose suprafisiol?gica de testosterona produz d?ficits de mem?ria de reconhecimento de objetos bem como preju?zos na mem?ria na tarefa da esquiva discriminativa em ratos machos adultos
APA, Harvard, Vancouver, ISO, and other styles
41

Au, Wai Ling. "Investigations of the bioavailability/bioequivalence of topical corticosteroid formulations containing clobetasol propionate using the human skin blanching assay, tape stripping and microdialysis." Thesis, Rhodes University, 2010. http://hdl.handle.net/10962/d1003221.

Full text
Abstract:
Currently, clinical trials in patients are required by most regulatory authorities for the assessment of bioequivalence of topical products where the drug is not intended for systemic absorption. Hence there is a dire need for suitable methods for the assessment of bioavailability and bioequivalence of such products since clinical safety and efficacy studies are expensive, time-consuming and require very large numbers of patients. Except for topical corticosteroid products where the human skin blanching assay/vasoconstrictor assay has been approved by the US FDA for bioequivalence assessment of those products, no other method has been “officially” approved for use in those investigations. However, a few alternative methods such as tape stripping and microdialysis have been pursued and considered to have the potential for use in ioequivalence/bioavailability studies. The human skin blanching assay was used to assess the bioequivalence of commercially available topical products containing 0.05% clobetasol propionate. Both visual and chromameter data were obtained and a commercially available topical corticosteroid product, Dermovate® cream was used as both the “Test” and the “Reference” product. The results indicated that both visual and chromametric assessments were comparable to each other and that either could be used for the assessment of the bioequivalence of topical products containing clobetasol propionate. The screening procedure was optimized to identify potential “detectors” for inclusion in the bioequivalence studies. This resulted in fewer subjects being required in a bioequivalence pivotal study, still having the necessary power to confirm bioequivalence using the human skin blanching assay. Another objective of this research was to re-visit tape stripping and other possible alternative methods such as dermal microdialysis and to optimize these procedures for bioequivalence assessment of topical formulations where the drug is not intended for systemic absorption. In the past few decades, tape stripping has been used to investigate bioavailability/bioequivalence of various topical formulations. This technique involves the removal of the stratum corneum to assess drug penetration through the skin. A draft FDA guidance for tape stripping was initially published but was subsequently withdrawn due to high variability and poor reproducibility. This research project used an optimized tape stripping procedure to determine bioavailability and establish bioequivalence between three commercially available formulations containing 0.05 % m/m clobetasol propionate. Furthermore, tape stripping was validated by undertaking a study to assess the bioequivalence of a 0.05% topical cream formulation (Dermovate® cream) using the same cream as both the “Test” and “Reference” product, in which bioequivalence was confirmed. The findings highlight the potential of tape stripping as an alternative method for the assessment of bioequivalence of clobetasol propionate formulations and may possibly be extended for use in other topical products. Microdialysis is another useful technique that can assess the penetration of topically applied substances which diffuses through the stratum corneum and into the dermis. Microdialysis has previously been successfully used for in vivo bioavailability and bioequivalence assessments of topical formulations. However, the drugs which were under investigation were all hydrophilic in nature. A major problem with the use of microdialysis for the assessment of lipophilic substances is the binding/adherence of the substance to the membrane and other components of the microdialysis system. As a result, this necessitates the development of a microdialysis system which can be used to assess lipophilic drugs. Intralipid® 20% was investigated and successfully utilized as a perfusate to recover a lipophilic topical corticosteroid, clobetasol propionate, in microdialysis studies. Hence, the bioavailability of clobetasol propionate from an extemporaneous preparation was determined in healthy human volunteers using microdialysis. These findings indicate that in vivo microdialysis can be used to assess lipophilic drug penetration through the skin. A novel approach to investigate drug release from topical formulations containing 0.05% clobetasol propionate using in vitro microdialysis was also undertaken. The in vitro findings were found to be in agreement with the results obtained using tape stripping to assess bioequivalence of the same commercially available products, namely Dermovate® cream, Dovate® Cream and Dermovate® ointment. These results indicate the potential to correlate in vitro with in vivo data for bioequivalence assessment of such topical dosage forms.
APA, Harvard, Vancouver, ISO, and other styles
42

Lee, Todd Allen. "Comparison of the cost-effectiveness of triamicinolone acetonide (azmacort HFA) and fluticasone propionate (flovent) in adult asthmatics in randomized controlled equivalence trial /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/7956.

Full text
APA, Harvard, Vancouver, ISO, and other styles
43

Carter, Michael Steven. "An Investigation into Carbon Flow through the Metabolic Networks ofRhodobacter sphaeroides." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1403873922.

Full text
APA, Harvard, Vancouver, ISO, and other styles
44

Berthelot, Valérie. "Contribution du propionate a la synthese des acides gras impairs et ramifies du tissu adipeux chez l'agneau : facteurs de variation alimentaires et metaboliques." Paris, Institut national d'agronomie de Paris Grignon, 2000. http://www.theses.fr/2000INAP0022.

Full text
Abstract:
Certaines carcasses d'ovins presentent des defauts de fermete de gras. L'analyse chimique des tissus adipeux de ces carcasses indique des teneurs anormalement elevees en acides gras impaires (agimp) et/ou ramifiees (agr). L'hypothese impliquerait un flux d'entree trop eleve de propionate d'origine ruminale, lors d'apports massifs d'aliments concentres, qui excederait la capacite du foie a le metaboliser en glucose. Le propionate et le methylmalonate (mma), metabolite issu de son catabolisme, constituerait un substrat de synthese de ces agimp et agr dans les tissus adipeux sous-cutanes des ovins. Notre travail a eu pour objectif d'etudier les mecanismes d'origine alimentaire (nature de l'energie et dynamique d'entree) qui conduisent a l'augmentation des agimp et agr, et de mieux identifier le role du propionate en tant que precurseur de ces acides gras. Il montre que, dans le cas d'apports massifs de propionate, une legere baisse d'efficacite de son prelevement hepatique est observee. Mais aucune production hepatique de mma n'a ete mesuree dans nos conditions experimentales. Ainsi, lors de l'ingestion de regimes riches en concentres, plus de propionate mais pas de mma est disponible pour les tissus peripheriques. Face a cette disponibilite accrue, les tissus adipeux sous-cutanes et principalement le tissu dorsal, presentent de fortes augmentations des proportions en agimp et agr. Lorsque la proportion d'agimp depasse 4% des acides gras totaux, la part des agimp resultant de la lipogenese de novo devient predominante dans les tissus sous-cutanes. La proportion d'agr issus de la lipogenese augmente parallelement. Le probleme de tissu adipeux mou avec augmentation de la proportion en agimp et en agr serait surtout lie au tissu
APA, Harvard, Vancouver, ISO, and other styles
45

Roule-Woiry, Karine. "Biocatalyse solide-gaz : application à la synthèse d'esters à label naturel." La Rochelle, 2001. http://www.theses.fr/2001LAROS102.

Full text
Abstract:
Procédé biotechnologique, la biocatalyse solide/gaz pourrait permettre de produire des arômes à label naturel à un coût inférieur à celui des extraits naturels. Les travaux réalisés prouvent la faisabilité technique et la viabilité économique de la production d'esters naturels par ce procédé à l'échelle industrielle. La synthèse de propionates d'alkyle a été catalysée par la lipase B de Candida antarctica (Novozym 435) dans des réacteurs solide/gaz à lit fixe, au laboratoire et à l'échelle préindustrielle. Dans les deux cas, la synthèse de propionate d'éthyle a été utilisée comme modèle d'étude. D'après les essais menés au laboratoire, le comportement du réacteur solide/gaz obéit au modèle d'un réacteur à lit fixe à écoulement de type piston. L'activité catalytique du réacteur à l'équilibre thermodynamique est essentiellement due aux 2/5 du catalyseur, situé en entrée du réacteur ; la perte d'activité de ce dernier est d'ailleurs plus rapide. La pression (0,25 à 0,75 atm) ou la nature du gaz vecteur (air ou azote) n'affectent pas la stabilité du catalyseur, en revanche, certains substrats entraînent une perte d'activité catalytique accélérée. La variation d'énergie libre et les conditions de productivité optimale ont été déterminées pour la synthèse de sept esters et utilisées pour leur transfert à l'échelle pilote. Une installation pilote préindustrielle a été mise en place et validée par la production de lots-tests de 50 à 200 kg de cinq propionates d'alkyle, avec une productivité minimale de 2kg/h. Le retraitement de phases issues d'une production est également possible. Le taux de conversion des substrats reste inférieur à celui obtenu au laboratoire à cause des effets du changement d'échelle sur le tassage et le maintien du lit catalytique et d'un échauffement important de ce dernier, dû au caractère exothermique de la réaction. Ce dernier représente actuellement la principale limite aux performances du procédé
As a biotechnological process, gas/solid biocatalysis is a valuable way to produce natural aromas at a lower cost than natural extracts. Technological and economical feasibility studies related to the production of natural esters at an industrial scale have been carried out. Lipase B from Candida antarctica has been used to catalyse alkyl propionate synthesis in gas/solid fixed bed reactors, both at laboratory and industrial scales. In both cases, ethyl propionate synthesis has been chosen as a model reaction. At the laboratory scale, the gas/solid reactor has been shown to obeys a piston like model. At the thermodynamic equilibrium, more than 70% of the reactor catalytic activity is due to the 2/5th of the catalyst, located at the reactor entry. In fact, the loss of catalytic activity is faster at the reactor entry. Pression (0. 25 to 0. 75 atm) or vector gas (air or nitrogen) do not seem to affect the catalyst stability whereas some substrates do. For the synthesis of seven esters, thermodynamic results and best productivity conditions were determined at the laboratory scale and used to fix production parameters at the pilot scale. A preindustrial plant has been set up and tested through the production of five alkyl propionates. In most cases, a minimal productivity of 2 kg/h was reached. Reprocessing of a failed batch and recycling of an aqueous phase containing non transformed substrates were also shown to be possible. The conversion rate is still lower at that scale than at the laboratory one due to effects of the scale-up. In particular, the packing down of the catalyst bed and its overheating, which is a consequence of the exothermic character of the reaction, are up to now the main limits to the process performances
APA, Harvard, Vancouver, ISO, and other styles
46

Aquino-Ramos, Jorge Luis 1961. "Influence on milk protein percentage of isocaloric infusions of glucose in the rumen, or propionate and acetate in the duodenum of cows fed dry rolled sorghum." Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/282163.

Full text
Abstract:
Experiments were conducted to elucidate mechanisms of increased milk protein percentage in cows fed diets containing steam flaked (SFS) vs dry rolled (DRS) sorghum grains. In experiment 1 treatments were: DRS diet plus duodenal infusion of 30% sodium acetate (DA), or SFS diet plus duodenal water infusion (SFS). In the experiment 2 the DRS diet plus duodenal infusion of 23% sodium propionate (DP), was compared with the DRS diet plus ruminal infusion of 21% glucose (RG). Sorghum was 35% of DM in all diets and infusates were 5L/d. The SFS diet tended (P .19) to increase milk protein content and decrease ruminal pH. The DA infusion increased FCM, and tended to increase fat% and yield. The RG infusion increased milk protein percent and decreased ruminal pH, and the DP infusion tended to decrease DMI. In experiment 3 treatments were: (1) SFS, (2) DA, and (3) RG. Diets and infused amounts were similar to previous trials. No parameters was affected by treatment, but milk protein percent, yield of milk and milk protein were numerically higher SFS than DA, similar to the previous study. Milk composition and production for cows fed DRS plus RG were the same as for cows fed SFS. An in situ trial was conducted to better characterize ruminal starch degradation. The same (DRS and SFS) diets were used as in infusions trials. Treatments were divided into diets and grains as follows: (1) diet DRS, (2) diet SFS, (3) grain DRS, and (4) grain SFS. Material for incubation was ground to pass a 2 mm screen and placed in the rumen for 2, 4, 8, 12, 24 and 48h. DM degradability was not affected by treatment. Starch degradability at 4, 8 and 12h and were higher for the SFS than for DRS diets or grains. In situ data support the infusion data which of higher ruminal starch degradability with SFS than DRS. The studies suggest that increased milk protein content resulting from feeding SFS compared with DRS relates more to increased ruminal starch fermentability (as stimulated by RG) than to greater absorption of acetate or propionate.
APA, Harvard, Vancouver, ISO, and other styles
47

Rigout, Sophie. "Effet de la disponibilité du glucose sur le métabolisme mammaire et conséquences sur la production du lait chez la vache laitière." Rennes, Agrocampus Ouest, 2002. http://www.theses.fr/2002NSARB136.

Full text
APA, Harvard, Vancouver, ISO, and other styles
48

Souza, Marília Trindade de Santana. "Síntese do propionato de carvacrol e estudo de suas propriedades anti-hiperalgésica e anti-inflamatória em protocolos." Pós-Graduação em Ciências Farmacêuticas, 2014. https://ri.ufs.br/handle/riufs/3931.

Full text
Abstract:
Terpenes are naturally occurring compounds obtained from the plants secondary metabolism. Despite presenting pharmacological effects, structural changes within their skeleton may increasing their pharmacological activity and attenuate the toxicological effects. Carvacrol is a phenolic monoterpene present in essential oils from plants belonging to the Labiatae family. Studies have demonstrated that carvacrol has anti-inflammatory activity. However, sctructural changes may reduce the effective dose of this monoterpene. Thus, in this study, we conducted an extensive systematic review evaluating the antiinflammatory activity of terpenes that suffered an alteration in its structure through synthesis and semi-synthesis, synthesize the carvacrol propionate (CP) from the carvacrol and evaluate its potential antinociceptive, anti-hyperalgesic and anti-inflammatory effects. To build the revision, it was made the search in Scopus, Embase and PubMed databases, using the descriptors anti-inflammatory agents, terpenes and structure activity relationship. In the experimental part, it was used Male Swiss mice (25-35 g) with 2 to 3 months age. The animals were divided in groups and were treated with CP (25, 50 and 100 mg/kg), vehicle (saline solution 0.9% + Tween 80 0.2%) or standard drug, intraperitoneally (i.p.). The antinociceptive effect was evaluated through the formalin (1%) protocol and the hot plate test. The mechanical hyperalgesia was evaluated through the algic agents injection: carragee nan (CG; 300 µg/paw), tumor necrosis factor-a (TNF-a; 100 pg/paw), prostaglandin E2 (PGE2; 100 ng/paw) or dopamine (DA; 30 µg/paw) using a digital analgesimeter (von Frey). To assess the anti-inflammatory effect, it was used the pleurisy and paw edema induced by GC (1 %) in digital plethysmometer. The cytotoxicity of CP was evaluated by the MTT colorimetric method. The experimental protocols were approved by the UFS ethics committee (CEPA/UFS: 35/12). The results are expressed as mean ± SEM and differences between groups were analyzed by one-way or two-way ANOVA test followed by Tukey or Bonferroni tests. Values of p < 0.05 were considered statistically significant. In systematic review, 27 papers were found concerning about terpenes structural modification and the evaluation of their anti-inflammatory activity. In the experimental part, the administration of CP produced a significant decrease (p < 0.01 and 0.001) in the test formalin-induced nociceptive in both phases of the test. In the hot plate test, the reaction time increased significantly at doses 50 and 100 mg/kg (p < 0.05, 0.01 and 0.001). CP inhibited the development of mechanical hyperalgesic induced by all agents tested (p < 0.05, 0.01 and 0.001). In the evaluation of anti-inflammatory activity, the treatment with CP was able to decrease significantly the leukocyte recruitment (p < 0.001), the TNF-a (p < 0.001), the IL-1ß (p < 0.05) and protein leakage (p < 0.01). In addition, the paw edema induced by CG in mice was inhibited significantly by CP (p < 0.05, 0.01 and 0.001). Thus, it is concluded that the CP attenuates nociception, mechanical hyperalgesia and inflammation, through an inhibition of cytokines. Therefore, structural modification terpene can be an interesting alternative for obtaining molecules with pharmacological properties.
Os terpenos sao compostos naturais obtidos do metabolismo secundario das plantas. Apesar de apresentar efeitos farmacologicos, modificacoes estruturais realizadas no seu esqueleto podem levar o aumentando de suas atividades farmacologicas e atenuar os efeitos toxicologicos. Neste contexto, insere-se o carvacrol, um monoterpeno fenolico, presente em oleos essenciais de plantas pertencentes a familia Labiatae. Estudos comprovam a atividade farmacologica deste monoterpeno. No entanto, modificacoes estruturais podem diminuir a dose efetiva deste composto. Desta forma, no presente estudo realizamos uma extensa revisao sistematica que avaliou a atividade anti-inflamatoria de terpenos que sofreram modificacoes em sua estrutura, atraves de sintese. Adicionalmente, sintetizar o propionato de carvacrol (CP), a partir do carvacrol, e avaliar seus possiveis efeitos antinocicepivo, anti-hiperalgesico e anti-inflamatorio. Para construir a revisao, foi realizada a busca nas bases de dados Scopus, PubMed e Embase, utilizando os descritores agentes anti-inflamatorios, terpenos e relacao estrutura atividade. Ja para a parte experimental, foram utilizados camundongos Swiss machos (25-35 g) com 2 a 3 meses de idade. Os animais foram divididos em grupos e foram tratados com CP (25, 50 e 100 mg/kg), veiculo (solucao salina 0,9% + Tween 80 0,2%) ou droga padrao, por via intraperitoneal (i.p.). O efeito antinociceptivo foi avaliado utilizando o protocolo de formalina (1%) e o teste da placa quente. A hiperalgesia mecanica foi avaliada apos a administracao dos agentes algicos carragenina (CG; 300 Êg/pata), fator de necrose tumoral- ¿ (TNF- ¿; 100 pg/pata), prostaglandina E2 (PGE2; 100 .g/pata) ou dopamina (DA; 30 Êg/pata) utilizando o analgesimetro digital Von Frey. Na avaliacao do efeito antiinflamatorio utilizou-se o teste de pleurisia e edema de pata induzido por CG (1%) em pletismometro digital. A citotoxicidade foi avaliada atraves do metodo colorimetrico MTT. Os protocolos experimentais foram aprovados pelo comite de etica da UFS (CEPA/UFS: 35/12). Os resultados foram expressos como media } erro padrao da media e as diferencas entre os grupos foram analisadas por meio do teste de variancia ANOVA, uma via ou duas vias, seguido pelo teste de Tukey ou Bonferroni. Valores de p < 0,05 foram considerados estatisticamente significantes. Na revisao sistematica foram encontrados 27 artigos sobre modificacao estrutural de terpenos e atividade anti-inflamatoria. Na parte experimental, a administracao do CP produziu uma reducao significativa (p < 0,01 ou 0,001) no teste da nocicepcao induzida por formalina, em ambas as fases do teste. No teste da placa quente, o tempo de reacao aumentou significativamente nas doses de 50 e 100 mg/kg (p < 0,05; 0,01 ou 0,001). O CP tambem foi capaz de inibir o desenvolvimento da hiperalgesia mecanica induzida por todos os agentes testados (p < 0,05; 0,01 ou 0,001). Na avaliacao da atividade anti-inflamatoria, o tratamento com CP causou uma diminuicao significativa (p < 0,001) no numero total de leucocitos, diminuindo os niveis de TNF- ¿ (p < 0,001), IL-1 À (p < 0,05) e extravasamento de proteinas (p < 0,01). Alem disso, o edema de pata induzido por CG tambem foi inibido pelo CP (p < 0,05; 0,01 ou 0,001). Desta forma, conclui-se que o CP possui atividade antinociceptiva, anti-hiperalgesica e anti-inflamatoria, provavelmente por inibicao de citocinas. Dessa maneira, a modificacao estrutural em terpeno pode ser uma alternativa interessante para obtencao de moleculas com propriedades farmacologicas.
APA, Harvard, Vancouver, ISO, and other styles
49

Leidel, Ines. "Stabilisierung des Stoffwechsels bei Milchkühen im peripartalen Zeitraum." Doctoral thesis, Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-210059.

Full text
Abstract:
Einleitung: Bei Milchkühen häufen sich Erkrankungen in der Frühlaktation. Sie gehören zu den wichtigsten Ursachen frühzeitiger Merzung und damit der aktuell unbefriedigenden Nutzungsdauer. Ziele der Untersuchungen: Ziel dieser Arbeit war es, den Stoffwechsel von Milchkühen in der kritischen Übergangszeit vom Trockenstehen zur Laktation (Transitphase) durch drei verschiedene prophylaktische Maßnahmen zu stabilisieren: mittels Huminsäuren Belastungen aus dem Darm einschließlich Endotoxinen zu mindern, mit einem Ammoniumpropionat-Propylenglykol- Gemisch die Energieversorgung zu verbessern sowie mit Dexamethason-21-isonicotinat die Stoffwechselfunktion der Leber zu fördern sowie gleichzeitig Entzündungsprozesse infolge der Kalbung zu hemmen. Materialien und Methoden: Die Untersuchungen wurden in einem sächsischen Bestand an 312 Kühen der Rasse „Holstein Friesian“ randomisiert innerhalb eines Jahres durchgeführt. An jeweils 78 Kühe wurden 300 ml Ammoniumpropionat-Propylenglykol-Gemisch(C3) täglich vom 14. Tag ante partum (a.p.) bis zum 14. Tag post partum (p.p.) oral verabreicht; ebenfalls oral wurden 100 g Huminsäure-Fertigpräparat (HS-FP) bzw. 50 g Huminsäuren-Rohstoff (HS-RS) im selben Zeitraum appliziert, und Dexamethason-21-isonicotinat (DEXA21) wurde einmalig am 1. Tag p.p. intramuskulär in der Dosierung 0,02 mg/kg Körpermasse verabreicht. 78 unbehandelte Kühe dienten als Kontrollgruppe. Die Auswirkungen dieser Maßnahmen auf Gesundheit, Leistung und Stoffwechsel wurden durch klinische Untersuchungen, durch Blutkontrollen am 14. Tag a.p., am 3. und 28. Tag p.p. (Leukozyten, freie Fettsäuren [FFS], Bilirubin, ß-0H-Butyrat[BHB], Glucose, Cholesterol, Creatinkinase [CK], Aspartat-Amino-Transferase [ASAT], Glutamat-Dehydrogenase [GLDH], gamma-Glutaryl-Transferase [GGT], Protein, Albumin, Mg, Fe, Ca, anorganisches Phosphat [Pi], Na, K) sowie durch die Erfassung von Gesundheitsstatus, Milchleistung und Fruchtbarkeit zu bestimmten Zeitpunkten geprüft. Ergebnisse: Die verschiedenen prophylaktischen Maßnahmen hatten keinen signifikanten Einfluss auf Fruchtbarkeits- und Gesundheitsparameter. Bei den absoluten und fettkorrigierten Milchmengen konnten ebenfalls keine statistisch gesicherten Unterschiede zwischen den Versuchsgruppen und der Kontrollgruppe festgestellt werden. Der Milcheiweißgehalt von C3 28 d p.p. sowie der Milchfettgehalt von DEXA21 und C3 100 d p.p. waren signifikant erhöht. Die Ergebnisse der Blutuntersuchungen ergaben hauptsächlich am 3., aber auch am 28. Tag p.p. gesicherte Unterschiede bei wichtigen Stoffwechselparametern wie Glucose, Cholesterol, Bilirubin, Protein, Albumin, Ca, Fe und CK. Die einmalige Gabe von Dexamethason-21-isonicotinat am 1. Tag p.p. hatte den besten Einfluss auf den Leber- und Energiestoffwechsel. In dieser Gruppe waren am 3. Tag p.p. die Glucose-, Bilirubin-, Cholesterol-, Protein, Ca- und Fe-Konzentrationen sowohl gegenüber der KG wie auch gegenüber allen anderen Versuchsgruppen signifikant günstiger. Für die Albumin- und Na-Konzentrationen sowie die CK-Aktivität traf das gegenüber der Kontroll- sowie der C3-Gruppe zu. Der Einsatz der Wirkstoffe mit HS-RS, HS-FP sowie C3 führte ebenfalls zu positiven Effekten auf die Leistung und den Stoffwechsel gegenüber der Kontrollgruppe, jedoch ließen sich diese nur in wenigen Fällen statistisch sichern. Schlussfolgerungen: Die Applikation von Dexamethason-21-isonicotinat einen Tag p.p. stabilisiert signifikant den Stoffwechsel von Kühen nach dem Partus. Gleichartige Effekte auf Milch- und Fruchtbarkeitsleitung sowie die Morbidität konnten nicht gesichert nachgewiesen werden. Für Huminsäure-Rohstoff, Huminsäure-Fertigpräparat sowie Ammoniumpropionat-Propylenglykol-Gemisch waren solche Effekte tendenziell erkennbar, statistisch aber nicht zu sichern. Auch wenn besonders mit Dexamethason-21-isonicotinat der Stoffwechsel in Belastungssituationen kurzfristig stabilisiert werden kann, müssen generell Haltung und Fütterung analysiert sowie Mängel beseitigt werden
Problem: In dairy cattle diseases are common in early lactation. They are among the main causes of early culling and the current unsatisfactory productive life. Objective: The aim of this work was to stabilize metabolism of dairy cows in the critical transition period from standing dry to lactation by three different prophylactic applications: using humic acids to minimize strain from the gut including endotoxins, using ammonium propionate mixed with propylene glycol to improve energy supply and dexamethasone-21-isonicotinate to promote metabolic function of the liver and at the same time to inhibit inflammatory processes following parturition. Experimental design: The studies were performed in a Saxon dairy farm on 312 cows of the „Holstein Friesian\" breed, randomly performed within one year. 78 cows were administered orally 300 ml ammonium propionate mixed with propylene glycol (C3) daily from 14 days before parturition (a.p.) to 14 days after parturition (p.p.), another 78 cows 100 g of a humic acid drug (HS-FP) or 50 g of humic acid raw material (HS-RS) were administered orally in the same period and dexamethasone-21-isonicotinate (DEXA21) was applied intramuscularly to another 78 cows on the first day p.p. in a dose of 0.02 mg/kg body weight. 78 untreated cows were used as control group. The impact of these administrations on health, performance and metabolism has been measured by clinical examinations and blood tests on 14. day a.p., on 3. and 28. day p.p. (Leukocytes, free fatty acids [ FFS ], bilirubin, beta-0H-butyrate [BHB] , glucose, cholesterol, creatine kinase [CK], aspartate aminotransferase [AST], glutamate dehydrogenase [GLDH], gamma glutaryl transferase [GGT], protein, albumin, Mg, Fe, Ca, inorganic phosphate [Pi] , Na, K) and was verified by detection of health status, milk yield and fertility. Results: The different prophylactic administrations had no significant effect on fertility and health parameters. The absolute and fat- corrected milk yields also showed no statistically reliable differences between experimental groups and control group. Milk protein content in C3 28 days p.p. and milk fat content in DEXA21 and C3 100 days p.p. were significantly increased. Blood control results showed mainly on 3. and 28. day p.p. important differences in metabolic parameters, such as glucose, cholesterol, bilirubin, protein, albumin, Ca, Fe and CK, which are statistically secured. A single dose of dexamethasone-21- isonicotinate on first day p.p. had the best effect on liver and energy metabolism. Three days p.p. glucose, bilirubin, cholesterol, protein, Ca and Fe concentrations performed significantly better in DEXA21 group compared both to control group and all other treatment groups. For albumin and Na concentrations and CK activity that was true with respect to control and C3 group. The use of a humic acid drug, humic acid raw material and ammonium propionate mixed with propylene glycol had positive impact on performance and metabolism compared with control group too, but could be statistically secured in only a few cases. Conclusions: The application of dexamethasone-21-isonicotinate at the first day p.p. significantly stabilizes metabolism in cows after parturition. Similar effects on milk yield and fertility as well as morbidity could not be observed. For humic acid drug, humic acid raw material and ammonium propionate mixed with propylene glycol such effects tended to be recognizable, but cannot be statistically secured. Metabolism can be stabilized in short term stress situations with dexamethasone-21-isonicotinate, general care and feeding must be analyzed and deficiencies have to be eliminated
APA, Harvard, Vancouver, ISO, and other styles
50

Assunção, José Miguel Pestana. "Influence of slaughter season, muscle type and gluconeogenesis precursors on intramuscular fat quality of ruminant meats." Doctoral thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2012. http://hdl.handle.net/10400.5/4657.

Full text
Abstract:
Tese de Doutoramento em Ciências Veterinárias, especialidade de Segurança Alimentar
The aim of this study was to determine the influence of slaughter season and muscle type on nutritional quality of intramuscular fat (IMF) in Mirandesa-PDO (Protected Designation of Origin) veal, Charneca-PDO beef and organic beef, assessing to the quality and status that may contribute to market differentiation. The results suggest that the IMF content of PDO veal, PDO beef and organic beef was slightly affected by the slaughter season but markedly changed by the muscle type. The meat analysed had a high nutritional value, with favourable ratios of n-6/n-3 and contents of n-3 PUFA and α-tocopherol. Some studies indicate that increasing the stearoyl-CoA desaturase (SCD) expression and activity may significantly improve the nutritional quality of meat by decreasing the SFA content, while increasing rumenic acid content. This can be achieved by the administration of gluconeogenesis precursors, such as propylene glycol, which induces elevated propionate in the rumen and higher levels of blood insulin and glucose, resulting in the SCD activity elevation. Thus, the influence of dietary gluconeogenesis precursors (propylene glycol and calcium propionate mix; PP) and linseed oil on intramuscular fatty acid composition of lambs was assessed. Results suggest that gluconeogenesis precursors modify the biohydrogenation pathway and reduce the rumenic acid concentration. Linseed oil supplementation increased meat concentration of α-linolenic acid, as well as most of the C18 biohydrogenation intermediates, including vaccenic acid and rumenic acids. In conclusion, regarding the lipid composition of IMF, the studied PDO and organic meats have a high nutritional value, contributing to the consumer`s confidence on these products. The fatty acid profile of lamb’s IMF was slightly affected by PP, without clear effects on insulinaemia and delta-9 desaturation, demanding future research on this subject.
RESUMO - Influência da sazonalidade, do tipo de músculo e de precursores da neoglucogénese na qualidade da gordura intramuscular de carne de ruminantes - Neste trabalho estudou-se o efeito da sazonalidade do abate e do tipo de músculo na qualidade da gordura intramuscular das carnes Mirandesa-DOP (Denominação de Origem Protegida) e Charneca-DOP, e da carne biológica, de modo a avaliar a qualidade e reputação alegada como fator diferenciador no mercado. Os resultados sugerem que a composição de ácidos gordos da gordura intramuscular das carnes analisadas foi influenciada ligeiramente pela sazonalidade do abate mas fortemente pelo tipo de músculo. Apesar desta variação, todas as carnes analisadas têm um elevado valor nutricional apresentando um índice favorável n-6/n-3 e teores elevados de n-3 PUFA e α-tocoferol. Alguns estudos indicam que o aumento da atividade da Δ-9 dessaturase pode melhorar a qualidade nutricional da carne, através da diminuição dos ácidos gordos saturados e do aumento do teor de ácido ruménico. Isto pode ser possível pela administração de precursores neoglucogénicos, tais como o propilenoglicol que induz o aumento do propionato no rúmen e aumenta os níveis sanguíneos de insulina e glucose, resultando no aumento da atividade da Δ-9 dessaturase. Assim foi avaliado o efeito da suplementação da dieta com propilenoglicol e propionato de cálcio, bem como óleo de linho, na composição lipídica da gordura intramuscular da carne de borrego. Os resultados sugerem que os precursores neoglucogénicos alteram a biohidrogenação ruminal e diminui o teor de ácido ruménico. A suplementação com óleo de linho aumenta o teor de ácido α-linolénico da carne, bem como a maioria dos C18 intermediários da biohidrogenação, incluindo os ácidos vacénico e ruménico. Em conclusão, a composição lipídica da gordura intramuscular das carnes de bovino DOP estudadas e da carne biológica apresenta um elevado valor nutricional, contribuindo para confiança do consumidor sobre estes produtos O perfil dos ácidos gordos da gordura intramuscular da carne de borrego é ligeiramente influenciado pelos precursores, sem efeitos claros na insulinemia e na Δ-9 dessaturase, exigindo-se estudos futuros sobre este assunto.
FCT - SFRH/PROTEC/2009/50138 and Co-financed by the grant PTDV/CVT/2006/66114
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography