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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

SCF - Engineered powders for delivery of budesonide from passive DPI devices

York, Peter, Lobo, J.M., Palakodaty, S., Schiavone, H., Clark, A., Tzannis, S.T. January 2005 (has links)
No / The objective of this study was to develop SEDS-engineered budesonide particles suitable for dry powder inhalation delivery and to evaluate their aerosol performance across a range of passive dry powder inhalers (DPI). SEDS budesonide powders were manufactured in Nektar's SCF manufacturing plant and compared to the micronized drug and commercial powder (Pulmicort Turbuhaler, AstraZeneca). Aerosol performance was evaluated by determining emitted dose (ED) by a variation of the USP method and fine particle fraction (FPF) using Andersen cascade impaction. The SCF powder dispersed best in the Turbospin and Eclipse devices, exhibiting high EDs (70%-80%) and relatively low variability (RSD 8%-13%). Regardless of the device, the SEDS material outperformed both the micronized drug and the commercial powder, while exhibiting good batch-to-batch reproducibility (RSD <5%). All powders exhibited flow rate-dependent ED, albeit for the SEDS material it was minimized at reduced fill weights. This was attributed to inadequate and variable powder clearance from the capsules at low inspiratory flow rates, which was more pronounced in the Eclipse and Cyclohaler. The results demonstrate that SEDS is an attractive particle-engineering process that may enhance pulmonary performance of budesonide and possibly facilitate development of other small molecule pulmonary products in passive DPI.
22

In-Vitro In-Vivo Correlation (IVIVC) of Inhaled Products Using Twin Stage Impinger

Al Ayoub, Y., Buzgeia, Asma, Almousawi, Ghadeer, Mazhar, H.R.A., Alzouebi, B., Gopalan, Rajendran C., Assi, Khaled H. 08 December 2021 (has links)
Yes / In vitro dissolution testing as a form of quality control has become a necessity in the pharmaceutical industry. As such, the need to establish a method that investigates the in vitro dissolution profile of inhaled products should be taken into account. The prime focus in this study was to examine the in-vitro in-vivo correlation utilising a modified version of the Twin Stage Impinger and to promote an in vitro dissolution model by enhancing the Fine Particle Dose (FPD) collection method for dry powder inhalers. The Twin Impinger was modified by inserting a stainless steel membrane holder disk in the base of the lower chamber. The design, with optimum drug deposition, was adopted for the dissolution study of budesonide and salbutamol. Afterwards, the membrane holder system was placed in the bottom of the dissolution vessel. Phosphate buffer saline (PBS), simulated lung fluid (SLF, Gamble solution) and Phosphate buffer (PB) were used in the study. The paddle dissolution apparatus, containing 300 mL of the medium, was operated at 75 rpm paddle speed. Samples were collected at defined time intervals and analysed using a validated HPLC method. The largest proportion of the budesonide dose was dissolved in PBS compared to PB and SLF. This was due to the presence of surfactant (0.2% w/v polysorbate), which enhances the wettability and the solubility of the poorly soluble drug (budesonide). The similarity factors for PBS and PB were 47.6 and 69.7, respectively, using SLF as a reference, whereas the similarity factor for salbutamol dissolution between PB and SLF was 81.3, suggesting PB is a suitable substitute. Comparison using both the predicted and actual in vivo pharmacokinetics (PK) values of the two drugs, as well as the pattern of their Concentration-Time (c-t) profiles, showed good similarity, which gave an indication of the validity of this in vitro dissolution method.
23

Performance of two different types of inhalers : influence of flow and spacer on emitted dose and aerodynamic characterisation

Almeziny, Mohammed Abdullah N. January 2009 (has links)
This thesis is based around examination of three mainstream inhaled drugs Formoterol, Budesonide and Beclomethasone for treatment of asthma and COPD. The areas investigated are these which have been raised in reports and studies, where there are concern, for drug use and assessment of their use. In reporting this work the literature study sets out a brief summary of the background and anatomy and physiology of the respiratory system and then discuses the mechanism of drug deposition in the lung, as well as the methods of studying deposition and pulmonary delivery devices. This section includes the basis of asthma and COPD and its treatment. In addition, a short section is presented on the role of the pharmacist in improving asthma and COPD patient's care. Therefore the thesis is divided into 3 parts based around formoterol, budesonide and beclomethasone. In the first case the research determines the in-vitro performance of formoterol and budesonide in combination therapy. In the initial stage a new rapid, robust and sensitive HPLC method was developed and validated for the simultaneous assay of formoterol and the two epimers of budesonide which are pharmacologically active. In the second section, the purpose was to evaluate the aerodynamic characteristics for a combination of formoterol and the two epimers of budesonide at inhalation flow rates of 28.3 and 60 L/min. The aerodynamic characteristics of the emitted dose were measured by an Anderson cascade impactor (ACI) and the next generation cascade impactor (NGI). In all aerodynamic characterisations, the differences between flow rates 28.3 and 60 were statistically significant in formoterol, budesonide R and budesonide S, while the differences between ACI and NGI at 60 were not statistically significant. Spacers are commonly used especially for paediatric and elderly patients. However, there is considerable discussion about their use and operation. In addition, the introduction of the HFAs propellants has led to many changes in the drug formulation characteristics. The purpose of the last section is to examine t h e performance of different types of spacers with different beclomethasone pMDIs. Also, it was to examine the hypothesis of whether the result of a specific spacer with a given drug/ brand name can be extrapolated to other pMDIs or brand names for the same drug. The results show that there are different effects on aerodynamic characterisation and there are significant differences in the amount of drug available for inhalation when different spacers are used as inhalation aids. Thus, the study shows that the result from experiments with a combination of a spacer and a device cannot be extrapolated to other combination.
24

Performance of two different types of inhalers. Influence of flow and spacer on emitted dose and aerodynamic characterisation.

Almeziny, Mohammed A.N. January 2009 (has links)
This thesis is based around examination of three mainstream inhaled drugs Formoterol, Budesonide and Beclomethasone for treatment of asthma and COPD. The areas investigated are these which have been raised in reports and studies, where there are concern, for drug use and assessment of their use. In reporting this work the literature study sets out a brief summary of the background and anatomy and physiology of the respiratory system and then discuses the mechanism of drug deposition in the lung, as well as the methods of studying deposition and pulmonary delivery devices. This section includes the basis of asthma and COPD and its treatment. In addition, a short section is presented on the role of the pharmacist in improving asthma and COPD patient¿s care. Therefore the thesis is divided into 3 parts based around formoterol, budesonide and beclomethasone. In the first case the research determines the in-vitro performance of formoterol and budesonide in combination therapy. In the initial stage a new rapid, robust and sensitive HPLC method was developed and validated for the simultaneous assay of formoterol and the two epimers of budesonide which are pharmacologically active. In the second section, the purpose was to evaluate the aerodynamic characteristics for a combination of formoterol and the two epimers of budesonide at inhalation flow rates of 28.3 and 60 L/min. The aerodynamic characteristics of the emitted dose were measured by an Anderson cascade impactor (ACI) and the next generation cascade impactor (NGI). In all aerodynamic characterisations, the differences between flow rates 28.3 and 60 were statistically significant in formoterol, budesonide R and budesonide S, while the differences between ACI and NGI at 60 were not statistically significant. Spacers are commonly used especially for paediatric and elderly patients. However, there is considerable discussion about their use and operation. In addition, the introduction of the HFAs propellants has led to many changes in the drug formulation characteristics. The purpose of the last section is to examine t h e performance of different types of spacers with different beclomethasone pMDIs. Also, it was to examine the hypothesis of whether the result of a specific spacer with a given drug/ brand name can be extrapolated to other pMDIs or brand names for the same drug. The results show that there are different effects on aerodynamic characterisation and there are significant differences in the amount of drug available for inhalation when different spacers are used as inhalation aids. Thus, the study shows that the result from experiments with a combination of a spacer and a device cannot be extrapolated to other combination.
25

IgA Nephropathy – Mucosal Immunity and Treatment Options

Smerud, Hilde Kloster January 2012 (has links)
In the present studies we have explored the link between food hypersensitivity and IgA nephropathy (IgAN) and evaluated treatment options in primary and recurrent disease. Approximately one third of our IgAN patients had a rectal mucosal sensitivity to gluten, as demonstrated by increased local mucosal nitric oxide production and/or myeloperoxidase release after gluten challenge. The gluten sensitivity seemed to be an innate immune reaction unrelated to the pathogenesis of celiac disease. Approximately half of the patients had a rectal mucosal sensitivity to soy or cow’s milk (CM). The levels of IgG antibodies to alfa-lactalbumin, beta-lactoglobulin and casein were significantly higher in CM sensitive as compared with non-sensitive IgAN patients, indicating that an adaptive immune response might be involved in addition to the innate immune reaction observed. With the knowledge of gastrointestinal reactivity enteric treatment was considered as a potential new treatment approach of IgAN. A 6-month prospective trial demonstrated proof-of-concept for the use of enteric budesonide targeted to the ileocaecal region of IgAN patients. We observed a modest, but significant reduction in urine albumin, a minor reduction of serum creatinine and a modest increase of eGFR calculated by the MDRD equation. eGFR calculated from the Cockcroft-Gault formula and cystatin C was not changed. In a retrospective study recurrence of IgAN and graft loss was evaluated in Norwegian and Swedish patients having received a primary renal transplant due to IgAN. Adjusting for relevant covariates, a multiple Cox-regression analysis on time to IgAN recurrence showed that use of statins was associated with reduced risk of recurrence and reduced risk of graft loss. The time lag from diagnosis to first transplantation and female gender were also associated with lower risk of recurrence. Improved graft survival was associated with related donor, low donor age and no or low number of acute rejection episodes.
26

Ventilation-perfusion relationships and respiratory drive in chronic obstructive pulmonary disease : with special reference to hypoxaemia, sleep quality and treatment with inhaled corticosteroid /

Sandek, Karin, January 2002 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2002. / Härtill 5 uppsatser.
27

High Performance Liquid Chromatography Assay Method for Simultaneous Quantitation of Formoterol and Budesonide in Symbicort Turbuhaler

Assi, Khaled H., Chrystyn, Henry, Tarsin, W. January 2006 (has links)
No / A sensitive and rapid high performance liquid chromatography method has been developed and used for the simultaneous determination of formoterol and budesonide in Symbicort Turbuhaler when assessing the aerodynamic characteristics of the emitted dose using Pharmacopoeial methods. This capability results in both time and cost saving. The mobile phase composition was acetonitrile-5 mM sodium dihydrogen orthophosphate, pH 3 (60: 40% v/v), and was passed at 1.5 ml min-1 through a C18 column with a UV detection (wavelength 214 nm). The method was shown to give good analytical performance in terms of linearity, precision (using phenylpropanolamine as an internal standard), sensitivity and solution stability. The intra-day precision for both formoterol and budesonide were 0.75% and 1.11%, respectively (n = 10). The limit of quantitation for formoterol was 10 ¿g L-1 and for budesonide was 120 ¿g L-1, and the limit of detection were 3 and 30 ¿g L-1, for both formoterol and budesonide, respectively. The method has been applied to determine the content of the emitted dose and the fine particle dose of Symbicort Turbuhaler.
28

Development of dry powder Inhaler and nebulised nanoparticles formulations of chrysin for the potential treatment of asthma. Development of dry powder inhaler of chrysin and nebulised nanoemulsion combination of chrysin and budesonide; Evaluating the anti-inflammatory activity of the combination formulation of chrysin and budesonide for asthma

Oum, Rahaf January 2022 (has links)
Chrysin is a flavonoid that can be used as a medication for asthma and chronic obstructive pulmonary disease due to its anti-inflammatory activities. However, no studies have investigated the effectiveness of an inhaled formulation of chrysin on its own or in combination with corticosteroids. Therefore, this study aimed to assess the aerosol performance of chrysin formulations as well as the performance of combined formulations of chrysin and budesonide. Dry powder inhaler formulations were used first, where chrysin was processed using three different techniques, namely ball-milling, sonocrystallisation, and spray drying, to obtain a suitable particle size for inhalation. The highest fine particle fraction was 27% when the sonocrystallised samples were used. As the lung deposition was relatively low, budesonide was not added to the formulations. Next, liquid formulations of chrysin and budesonide were prepared in two concentrations using limonene and oleic acid as the oil phase. In a comparison of low and high drug concentrations of the formulations, the FPF of the formulations prepared with limonene ranged from 45% to 53.3% and from 49.3% to 53.9% for chrysin and budesonide, respectively; by contrast, the FPF of the formulations prepared with oleic acid oil ranged from 41% to 50.4% and from 46% to 53.3% for chrysin and budesonide, respectively. A genotoxicity study confirmed the safety of these combined formulations, and an anti-inflammatory study confirmed the potential for chrysin to be used with budesonide in a combined formulation; thus, chrysin’s anti-inflammatory efficacy can be improved and the required inhaled dose can be reduced.
29

DEVELOPMENT AND VALIDATION OF A SEMI-PHYSIOLOGICAL PHARMACOKINETIC (PBPK) MODEL TO PREDICT SYSTEMIC AND PULMONARY EXPOSURES AFTER INTRAVENOUS, ORAL ADMINISTRATION AND PULMONARY INHALATION OF SELECTED DRUGS, BUDESONIDE, TOBRAMYCIN AND CIPROFLOXACIN, IN HUMANS

Hanna, Bishoy 01 January 2018 (has links)
Using a semi-PBPK modeling/quantitative meta-analysis approach, this project investigated what factors affect pulmonary and systemic exposures of Budesonide (BUD), Tobramycin (TOB), and Ciprofloxacin (CIP) after inhalation: Three structurally different pulmonary disposition models were developed for each drug, including pulmonary absorption (all three), excretion (TOB and CIP) and sequestration (TOB) in a peripheral and central lung compartment. Systemic disposition parameters were estimated using available human mean plasma (cp(t)) and sputum (cs(t)) concentration profiles after IV administration, and GI absorption parameters were estimated from these profiles after oral administration. Pulmonary disposition parameters were estimated from cp(t) and cs(t) profiles after inhalation using various devices along with their published pulmonary deposition characteristics. Appropriate covariate models accounted for effects of Cystic Fibrosis on the systemic disposition/GI absorption for TOB and CIP. Monte Carlo Simulations (MCS) were used to optimize parameters and validate the final models and parameter spaces against published data. Despite limited available data, especially cs(t) for BUD and CIP (after IV administration), the point estimates for the final model parameters were mechanistically plausible for all three drugs and consistent with their known differences in physicochemical and ADME properties. Model predictions adequately described the observed cp(t) and cs(t) profiles as well as exposure metrics across studies. As the most lipophilic drug, BUD showed the fastest pulmonary absorption rates and highest Fpul (83%). TOB, a very hydrophilic drug, exhibited (intracellular) pulmonary sequestration, resulting in slow pulmonary absorption and excretion and low Fpul (10%). CIP - as zwitterion - showed relatively slow pulmonary absorption and excretion, leading to low Fpul (8%); pulmonary excretion accounted for 27% of CIP overall elimination. Results of a formal parameter sensitivity analysis demonstrated that, for all three drugs, after inhalation, (1) their systemic exposures (cp(t)) depend primarily on CLtot along with Fpul/sequestration combined with Foral; (2) increasing pulmonary exposures (cs(t)) can be accomplished by slowing down pulmonary absorption rates (kca) and/or slowing down mucociliary clearance from the lungs into the GI tract (kcm) – affirming the overall hypothesis guiding the project.
30

Clinical and Experimental Studies on Inflammatory Bowel Disease with special emphasis on Collagenous Colitis

Wagner, Michael January 2010 (has links)
This thesis describes studies in patients with inflammatory bowel disease (IBD) and collagenous colitis (CC). We investigated mucosal eosinophil and neutrophil granulocytes and T-cells involved in the inflammatory processes and aimed at determining whether these processes are reflected in the faecal (F) contents of specific proteins secreted by cells in the intestinal mucosa. Thus, we measured eosinophil cationic protein (ECP) and eosinophil protein X (EPX) and the neutrophil derived myeloperoxidase (MPO) and calprotectin (C); and in addition, chromogranin A (CgA), Chromogranin B (CgB) and secretoneurin (SN), derived from EEC cells and cells in the enteric nervous system. We found that a normalised FC level can serve as a surrogate marker for successful treatment in patients with IBD, but persistently high FC levels need further evaluation (study I). Furthermore, FC and F-MPO appear to relate better than F-EPX to treatment outcome in IBD. We evaluated F-ECP, F-EPX, F-MPO and FC as markers of disease activity and treatment outcome in patients with CC (study III) and concluded that F-ECP was the best discriminator of detecting active CC. Normalised F-ECP and F-EPX could serve as markers of successful treatment. We showed that the inflammation in CC is characterised by activated eosinophils, but that there is no neutrophil activity (study II). T-cells have a lower grade of activity in active CC than in control subjects. During budesonide treatment the normal activation of eosinophils and T-cells is restored, with concomitant clinical remission. The findings in studies II and III indicate that the eosinophils have an essential role in the pathophysiology of CC. Markedly higher values of F-CgA, F-CgB and F-SN were found in patients with CC than in those with IBD and controls (study IV) indicating a crucial role for the intestinal neuro-endocrine system in the pathogenesis of collagenous colitis.

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