• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 5
  • 4
  • 1
  • 1
  • Tagged with
  • 11
  • 10
  • 4
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Formulation, in vitro release and transdermal diffusion of diclofenac salts by implementation of the delivery gap principle / Hanri Smith

Smith, Hanri January 2013 (has links)
Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used in the treatment of inflammation and pain (Escribano et al., 2003:203). Diclofenac, a classical NSAID, is considerably more effective as an analgesic, antipyretic and anti-inflammatory drug than other traditional NSAIDs, like indomethacin and naproxen (Grosser et al., 2011:986). However, the use of diclofenac is known for its many side effects, such as gastric disorders, while fluid and sodium retention are also commonly observed (Rossiter, 2012:391). Since topical diclofenac offers a more favourable safety profile, it is a valuable substitute for oral NSAID therapy in the treatment of osteoarthritis (Roth & Fuller, 2011:166). The benefits of topically applied NSAIDs, compared to oral administration and systemic delivery, include the easy cessation of treatment, should effects become troublesome (Brown et al., 2006:177), the avoidance of extensive, first-pass metabolism (Cleary, 1993:19; Kornick, 2003:953; Prausnitz & Langer, 2008:1261; Lionberger & Brennan, 2010:225), reduced systemic side effects (Colin Long, 2002:41), convenience of application and improved patient compliance (Cleary, 1993:19; Prausnitz & Langer, 2008:1261). An approach that is often applied in optimising the solubility and dissolution rate of poorly water soluble, weak electrolytes is to prepare a salt of the active pharmaceutical ingredient (API) (Minghetti et al., 2007:815; O’Connor & Corrigan, 2001:281-282). Diclofenac is frequently administered as a salt, due to the high partition coefficient and very low water solubility of this molecule (Fini et al., 1999:164). Formulating for efficacy (FFETM) is a software programme designed by JW Solutions to facilitate the formulation of cosmetic ingredients or solvents into a product that would optimally deliver active ingredients into the skin. The notion is built upon solubility, i.e. solubility of the active ingredient in the formulation and solubility of the formulation in the skin. This programme could also be employed to optimise amounts of predetermined ingredients, to propose formulations that would ensure optimal drug delivery, to calculate the skin delivery gap (SDG) and to demonstrate transdermal permeation of active ingredients and excipients (JW Solutions Software, 2013a). When the SDG is known, it mathematically indicates the optimal active ingredient and topical delivery vehicle to use (JW Solutions, 2013b). In this study, diclofenac sodium (DNa), diclofenac diethylamine (DDEA) and diclofenac N-(2- hydroxyethyl) pyrrolidine (DHEP) were each formulated in the following emulgels: * An emulgel optimised towards the stratum corneum (SC) (enhancing drug delivery into this layer and deeper tissues) (oily phase ~30%), * A more hydrophilic emulgel (oily phase ~15%), and * A more lipophilic emulgel (oily phase ~45%). Components of the oily phase and its respective amounts, as well as the SDG of formulations were determined by utilising the FFETM software of JW Solutions (2013a). The aqueous solubilities of DNa, DDEA and DHEP were determined and their respective values were 11.4 mg/ml, 8.0 mg/ml and 11.9 mg/ml, all indicative of effortless percutaneous delivery (Naik et al., 2000:319). Log D (octanol-buffer distribution coefficient) (pH 7.4) determinations for DNa, DDEA and DHEP were performed and their values established at 1.270 (DNa), 1.291 (DDEA) and 1.285 (DHEP). According to these values, diclofenac, when topically applied as a salt in a suitable vehicle, should permeate transdermally without the aid of radical intervention (Naik et al., 2000:319; Walters, 2007:1312). Membrane release studies were also carried out in order to determine the rate of API release from these new formulations. Results confirmed that diclofenac was indeed released from all nine of the formulated emulgels. The more hydrophilic DNa formulation released the highest average percentage of diclofenac (8.38%) after 6 hours. Subsequent transdermal diffusion studies were performed to determine the diclofenac concentration that permeated the skin. The more hydrophilic DNa emulgel showed the highest average percentage skin diffusion (0.09%) after 12 hours, as well as the highest average flux (1.42 ± 0.20 μg/cm2.h). The concentrations of diclofenac in the SC-epidermis (SCE) and epidermis-dermis (ED) were determined through tape stripping experiments. The more lipophilic DNa emulgel demonstrated the highest average concentration (0.27 μg/ml) in the ED, while the DNa emulgel that had been optimised towards the SC, had the highest concentration in the SCE (0.77 μg/ml). / MSc (Pharmaceutics), North-West University, Potchefstroom Campus, 2014
2

Formulation, in vitro release and transdermal diffusion of diclofenac salts by implementation of the delivery gap principle / Hanri Smith

Smith, Hanri January 2013 (has links)
Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used in the treatment of inflammation and pain (Escribano et al., 2003:203). Diclofenac, a classical NSAID, is considerably more effective as an analgesic, antipyretic and anti-inflammatory drug than other traditional NSAIDs, like indomethacin and naproxen (Grosser et al., 2011:986). However, the use of diclofenac is known for its many side effects, such as gastric disorders, while fluid and sodium retention are also commonly observed (Rossiter, 2012:391). Since topical diclofenac offers a more favourable safety profile, it is a valuable substitute for oral NSAID therapy in the treatment of osteoarthritis (Roth & Fuller, 2011:166). The benefits of topically applied NSAIDs, compared to oral administration and systemic delivery, include the easy cessation of treatment, should effects become troublesome (Brown et al., 2006:177), the avoidance of extensive, first-pass metabolism (Cleary, 1993:19; Kornick, 2003:953; Prausnitz & Langer, 2008:1261; Lionberger & Brennan, 2010:225), reduced systemic side effects (Colin Long, 2002:41), convenience of application and improved patient compliance (Cleary, 1993:19; Prausnitz & Langer, 2008:1261). An approach that is often applied in optimising the solubility and dissolution rate of poorly water soluble, weak electrolytes is to prepare a salt of the active pharmaceutical ingredient (API) (Minghetti et al., 2007:815; O’Connor & Corrigan, 2001:281-282). Diclofenac is frequently administered as a salt, due to the high partition coefficient and very low water solubility of this molecule (Fini et al., 1999:164). Formulating for efficacy (FFETM) is a software programme designed by JW Solutions to facilitate the formulation of cosmetic ingredients or solvents into a product that would optimally deliver active ingredients into the skin. The notion is built upon solubility, i.e. solubility of the active ingredient in the formulation and solubility of the formulation in the skin. This programme could also be employed to optimise amounts of predetermined ingredients, to propose formulations that would ensure optimal drug delivery, to calculate the skin delivery gap (SDG) and to demonstrate transdermal permeation of active ingredients and excipients (JW Solutions Software, 2013a). When the SDG is known, it mathematically indicates the optimal active ingredient and topical delivery vehicle to use (JW Solutions, 2013b). In this study, diclofenac sodium (DNa), diclofenac diethylamine (DDEA) and diclofenac N-(2- hydroxyethyl) pyrrolidine (DHEP) were each formulated in the following emulgels: * An emulgel optimised towards the stratum corneum (SC) (enhancing drug delivery into this layer and deeper tissues) (oily phase ~30%), * A more hydrophilic emulgel (oily phase ~15%), and * A more lipophilic emulgel (oily phase ~45%). Components of the oily phase and its respective amounts, as well as the SDG of formulations were determined by utilising the FFETM software of JW Solutions (2013a). The aqueous solubilities of DNa, DDEA and DHEP were determined and their respective values were 11.4 mg/ml, 8.0 mg/ml and 11.9 mg/ml, all indicative of effortless percutaneous delivery (Naik et al., 2000:319). Log D (octanol-buffer distribution coefficient) (pH 7.4) determinations for DNa, DDEA and DHEP were performed and their values established at 1.270 (DNa), 1.291 (DDEA) and 1.285 (DHEP). According to these values, diclofenac, when topically applied as a salt in a suitable vehicle, should permeate transdermally without the aid of radical intervention (Naik et al., 2000:319; Walters, 2007:1312). Membrane release studies were also carried out in order to determine the rate of API release from these new formulations. Results confirmed that diclofenac was indeed released from all nine of the formulated emulgels. The more hydrophilic DNa formulation released the highest average percentage of diclofenac (8.38%) after 6 hours. Subsequent transdermal diffusion studies were performed to determine the diclofenac concentration that permeated the skin. The more hydrophilic DNa emulgel showed the highest average percentage skin diffusion (0.09%) after 12 hours, as well as the highest average flux (1.42 ± 0.20 μg/cm2.h). The concentrations of diclofenac in the SC-epidermis (SCE) and epidermis-dermis (ED) were determined through tape stripping experiments. The more lipophilic DNa emulgel demonstrated the highest average concentration (0.27 μg/ml) in the ED, while the DNa emulgel that had been optimised towards the SC, had the highest concentration in the SCE (0.77 μg/ml). / MSc (Pharmaceutics), North-West University, Potchefstroom Campus, 2014
3

Příprava a fytoextrakce 125-I značených farmak / Preparation and phytoextraction of 125-I labelled pharmaceuticals

Luptáková, Dominika January 2013 (has links)
Pharmaceuticals are group of organic substances with significant worldwide consumption in human and veterinary medicine. These compounds may be metabolized in the organism, but in some cases they remain unchanged and both are usually excreted via renal excretion in the native form or as metabolites. Large quantities of pharmaceuticals and their metabolites contaminate municipal wastewater. The wastewater treatment plants are unable to remove these substances completely, so they contaminate surface water, groundwater and soil as well. Due to the biological activity of pharmaceuticals, long - term effect may cause bacterial resistance, endocrine influence, DNA and renal damages in non-target organisms. The phytoextraction and the translocation of radiolabeled diclofenac with 125 I were experimentally studied by using of in vitro cultivated plants Helianthus annuus and Zea mays. Efficiency od phytoextraction was monitored as decrease of radioactivity of tested substance [125 I]diclofenac in Murashige-Skoog cultivation medium. Both species are able to extract tested substance during 8 to 10 days of cultivation, with efficiency approximately 85 % using Zea mays and 79 % using Helianthus annuus. Better extraction ability of diclofenac was observed at Helianthus annuus - 80 mg/ kg of dry weight compared...
4

Studium průběhu degradace xenobiotik a biologicky aktivních látek s využitím oxidu titaničitého / Study of xenobiotics and biologically active compounds degradation on titanium dioxide

Píšťková, Veronika January 2012 (has links)
Heterogenous photocatalysis using titanium dioxide seems to be a promising method for disposal xenobiotics from the environment. The aim of this diploma thesis is the study of degradation of selected xenobiotics and biologically active substrances applying this method. Theoretical part of diploma thesis deals with the principals of heterogenous photocatalysis by means of a semiconductor TiO2 and the examples of its possible application are mentioned too. The compounds which could be appropriate for a study of degradation were selected from the group of pharmaceuticals and pesticides. The properties of target substances and their environmental impact were described. Furthermore, a bibliographic search focused on the possibilities of their analytical determination was conducted. The experimental part of the thesis describes the experiments with photocatalyst in a form of powder as well as with immobilized photocatalyst in thin layer on a carrier. Identification and quantification of analytes was realized by high performance liquid chromatography with mass spectrometic detection.
5

Effects of Diclofenac on Fish Behavior : A Meta-Analysis / Effekter av Diklofenak på Fiskbeteende : En metaanalys

Sandström, Patrik January 2022 (has links)
Pharmaceuticals in aquatic environments have been put under increasing scientific scrutiny as they are frequently found as contaminants in natural waters, often entering via effluent water containing pharmaceutical residue from human excretion. Diclofenac is a frequently found non-steroidal anti-inflammatory drug [NSAID] in waters that has been shown to cause both acute and chronic effects on various aquatic organisms. A common method to assess the effects of sub-lethal exposures has been behavioral experiments, yet these tests are often not considered in regulatory decision-making. This study aimed to evaluate if diclofenac can cause behavioral changes in fish through a meta-analysis of existing literature. A total of 372 studies, identified from six different databases, were reviewed. A random-effects model was applied on four studies where behaviors acting as proxies for fish activity were measured in response to diclofenac exposure. It was found that diclofenac does not seem to affect the activity in fish in neither light nor dark conditions, with one potential exception at high exposure levels (>100 μg/L) in light conditions causing decreased activity. A comparison using available monitoring data in waters from national databases (including sampling between years 2005 and 2021) was used to illustrate that diclofenac concentrations in Sweden, and globally, do not exceed this latter value. Therefore, it appears unlikely that diclofenac will influence the activity in fish.
6

Účinnost technologie ČOV České Budějovice pro eliminaci farmak / Efficiency of the technology of WWTP České Budějovice for the elimination of pharmaceuticals

BARTOŇ, Jiří January 2013 (has links)
The main aim of this study was to investigate the efficiency of wastewater treatment plant (WWTP) in České Budějovice for the elimination of selected pharmaceuticals (carbamazepine, diclofenac, atenolol, metoprolol, sotalol, bisoprolol, valsartan, verapamil and tramadol) over a long time period (March 2011 - February 2012). Time-proportional 24 hours pooled samples of wastewater from influent and effluent of the WWTP were used to assess the efficiency of WWTP. The concentrations of target compounds were determined by using in line SPE/LC-MS/MS analysis. The average annual concentrations in the effluent of WTP were in the range of 0,019 microgram/l (verapamil) to 1,00 microgram/l (atenolol). Average annual efficiencies of pharmaceutical elimination in WWTP based on pooled samples were found in the case of carbamazepine (-22 %), tramadol (-15 %), sotalol (-1 %), diclofenac (15 %), metoprolol (16 %), verapamil (43 %), bisoprolol (48 %) and valsartan (85 %). The statistical analysis of daily results in the winter and in the summer period showed significantly higher efficiency of the WWTP in the summer for 5 target compounds (diclofenac, atenolol, valsartan, sotalol and bisoprolol). Removal efficiency for the rest of pharmaceuticals did not show significant differences. Elevated temperature and longer irradiation period in summer can positively affect biodegradation or increased photolysis respectively.
7

Which COX-inhibitor to which patient; an analysis of contemporary evidence including pharmacology and medicinal chemistry / Vilken COX-hämmare till vilken patient; en analys av kontemporär evidens inklusive farmakologi och läkemedelskemi

Persson, Jakob January 2018 (has links)
NSAIDs are among the most used drugs in the world. It is estimated that 30 million people take NSAIDs daily world-wide, without including drugs sold over the counter. They are effective in alleviating pain and inflammation. Even though they are very common there does not appear to be any clear-cut guidelines to when which NSAID should be used. It has therefore been the purpose of this thesis to analyze if there is a need to differentiate between different NSAIDs according to contemporary evidence. Since the withdrawal of rofecoxib in 2004 there has been a general idea that coxibs as a group are cardiotoxic, recent evidence suggests that this holds true for all NSAIDs however. As such this work included 5 drugs, three common over the counter non-selective NSAIDs; naproxen, ibuprofen and diclofenac as well as the two coxibs currently on the Swedish market; celecoxib and etoricoxib. Pubmed and google scholar were searched for relevant studies on the subject. The results showed that there is a need to differentiate between NSAIDs, however the clinical setting is complex and a one-size fits all solution is difficult to come by. Naproxen and moderate doses of celecoxib (100 mg b.i.d.) show the best cardiovascular profiles whilst etoricoxib, celecoxib and diclofenac show the best gastrointestinal profiles. Coxibs show similar upper GI-profiles as tNSAIDs if combined with PPI however PPI are not without adverse events and the lower GI is not affected by PPI. Longer half-life is in general the better option in situations with lasting pain since it has been shown that lower dosing intervals increase adherence. In terms of pain management there does not appear to be any differences in efficacy amongst different NSAIDs
8

Delovanje lekova registrovanih za neonkološke indikacije na eksperimentalni fibrosarkom hrčka / Effect of repurposing non-cancer drugs on experimental fibrosarcoma in hamsters

Popović Dušica 04 June 2019 (has links)
<p>Mnogi lekovi registrovani za razne druge indikacije mogu da deluju selektivno na tumorske receptore, signalne puteve, metaboličke procese, bioenergetske faktore, enzime, proteine, gene koji reguli&scaron;u proliferaciju, apoptozu i neoangiogenezu tumora ne pogađajući ove procese kod zdravih ćelija. Uvođenje novih lekova je izrazito dug, složen i skup proces istraživanja. Kori&scaron;ćenjem principa otkrivanja antikancerskog efekta kod već registrovanih lekova za druge indikacije, direktno se utiče na skraćivanje vremena i tro&scaron;kova istraživanja. Eksperimentalno je ispitana efikasnost antitumorskog delovanja mebendazola, metformina, itrakonazola, diklofenaka, nitroglicerina i deoksiholne kiseline na fibrosarkom hrčka izazvan BHK21/C13 tumorskom ćelijskom linijom praćenjem veličine i histologije lečenih tumora. Eksperimentalno je ispitana mogućnost primene deoksiholne kiseline, nitroglicerina, kofeina i itrakonazola kao adjuvansa u kombinaciji sa pojedinim ispitivanim lekovima (metformin, itrakonazol, diklofenak) za lečenje fibrosarkoma hrčka. Kako je ispitivanje vr&scaron;eno na mladuncima imladim hrčkovima i kako su sarkomi najče&scaron;ći u dečijem uzrastu, definisanje potencijalne antikancerske uloge ispitivanih lekova se odnosi prvenstveno na njihovu primenu u pedijatriji. Pokazano je da metformin, kombinacije metformina sa kofeinom, metformina sa itrakonazolom i metformina sa nitroglicerinom deluju u pogledu svih ispitivanih parametara tumora antitumorski na fibrosarkom hrčka. Kofein, itrakonazol i nitroglicerin pojačavaju antitumorsko dejstvo metformina na fibrosarkom hrčka. Tokom svih eksperimenata realizovanih u okviru ove disertacije, pokazalo se da nije bilo delotvornog tretmana, koji ne sadrži metformin.</p> / <p>Many drugs registered for various other indications can act selectively to tumor receptors, signaling pathways, metabolic processes, bioenergetic factors, enzymes, proteins, genes that regulate proliferation, apoptosis, and neoangiogenesis of the tumor without affecting these processes in the healthy cells. The introduction of new drugs is a very long, complex and expensive process of research. Using the principle of detecting the anticancer effect in already registered drugs for other indications, directly affects the reduction of time and cost of research. The efficacy of mebendazole, metformin, itraconazole, diclofenac, nitroglycerin and deoxycholic acid antitumor activity on hamster fibrosarcinoma induced experimentally by the BHK21/C13 tumor cell line was tested by monitoring the size and histology of the treated tumors. The possibility of using deoxycholic acid, nitroglycerin, caffeine and itraconazole as an adjuvant in combination with investigated drugs (metformin, itraconazole, diclofenac) for the treatment of hamster fibrosarcoma has been experimentally tested. As the examination was carried out on young cubs and young hamsters and that sarcomas are the most common in childhood, defining the potential anti-cancer role of the investigated drugs relates primarily to their application in pediatrics. Metformin, combinations of metformin with caffeine, metformin with itraconazole and metformin with nitroglycerin have shown antitumor action on the hamster fibrosarcoma in terms of all tested tumor parameters. Caffeine, itraconazole and nitroglycerin increase the antitumor effect of metformin on the hamster fibrosarcoma. During all the experiments carried out within this dissertation, there has been no effective treatment, which does not contain metformin.</p>
9

Vlastnosti komplexů aminojílu a biologicky aktivních látek / Properties of aminoclay complexes and biologically active substances

Dušek, Jakub January 2020 (has links)
This paper builds on previous research of aminoclay complexes in undergraduate studies. Theoretical part deals with study of current problems of aminoclay complexes with bioactive substances and the choice of substances for complexing with aminoclay. The experimental part consists of preparation of aminoclay complexes with selected bioactive agents at various concentrations. Verification of binding of bioactive agents to the aminoclay matrix was performed by Elemental Analysis (EA) and Fourier-transform infrared spectroscopy (FT-IR). For finding of the bound amount of bioactive substance were used the Ultra Performance Liquid Chromatography (UPLC®) and analysis of the cytotoxic properties of the formed complexes by used by the MTT assay. The main motivation of this study is to create new complexes with improved characteristics that would replace existing forms of substances used in pharmaceutical and biomedical applications.
10

Vývoj a charakterizace hydrogelů s obsahem huminových látek pro kosmetické a farmaceutické aplikace / Material characterization of novel hydrogels containing humic substances intended for pharmaceutical and cosmetic applications

Pavlicová, Renata January 2016 (has links)
This thesis is focused on the development and characterization of hydrogels containing humic substances with possible use in cosmetic and pharmaceutical industries. This work follows on the bachelor thesis, theoretical and experimental part is based on already acquired knowledge. The aim of this work was to develop a literature review focusing on the potential use humic gels in practice and also to enhance the consistency of other active ingredients. Based on this literature review, the main aim was to prepare model humic hydrogels with selected active ingredients and their characterization by basic methods of material analysis. These basic methods were especially rheology and visual assessment of consistency during the preparation, then the samples were subjected process of drying and swelling. Experimental results showed considerable influences during the preparation and composition of each sample, which then reflected in their structure and consistency. Furthermore, it was found that the suitable composition and combination of ingredients form hydrogels acceptable characteristics for further use in cosmetic or pharmaceutical applications.

Page generated in 0.0318 seconds