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The background of this study is increase in the ageing population and in medication use. Aged-related changes in pharmacodynamics and pharmacokinetics may change medication response in elderly patients and lead to adverse reactions. For elderly people the risk of being hospitalized due to adverse drug reactions is four times higher than for younger people. Many of these problems could be prevented by avoiding the use of certain drugs in the elderly. Several criteria have been developed to assess medication appropriateness in the elderly. The aim of this study was to develop a new Finnish Medication Risk Assessment (MRA) tool to be used by trained nurses to assess the presence of risks related to use of medicines in outpatients aged 65 years and older. A preliminary tool was developed through a comprehensive literature review of tools to indicate appropriateness and risks of elderly medications, and through expert opinions. The tool was then validated by using three-round Delphi-method. Delphi-method is a qualitative consensus method which is based on group judgement of a subject matter. The first and the second Delphi-rounds measured the tool's suitability and the third Delphi-round measured the importance of the items of the tool in estimating risks related to the use of medications of elderly patients. In this study, 33 expert geriatric panelists were approached of whom 11 physicians, three pharmacists MSc (Pharm.) and four nurses agreed to participate. The results from the Delphi-rounds were evaluated both quantitatively and qualitatively. Through the three-round Delphi-method was developed a MRA -tool that contains 19 items. According to the panelists the items of the tool are either important or moderately important. This indicates that the tool is valid to estimating medication risks in use of medications in this population. Further studies are needed to test the tool among nurses and patients. The MRA -tool was primary developed for estimating risks in medication use, but it could also be used for educational purposes. In the future, it is possible to implement safer and more appropriate pharmaceutical treatment for elderly patients by using this Medication Risk Assessment -tool.

The medicines information and counseling given by health care professionals are essential in supporting patients' medication therapy. Given that medication therapies are often associated with medicine-related problems among the elderly, proper knowledge on medicines and their use is especially important for this particular patient group. Benzodiazepines and related drugs are of special concern in the elderly. Despite the current care guidelines, they are commonly used by the elderly, often also regularly and long-term basis. Benzodiazepines and related drugs are associated with multiple potential adverse drug reactions that their elderly users should be aware of. This study aimed at assessing the knowledge on medications, and needs and sources of medicines information on benzodiazepines and related drugs in the elderly. Especially, medicines information related to benefits and adverse drug reactions was studied. Additionally, data on use and subjective experiences of benzodiazepines or related drugs in the elderly were explored. Structured interviews were conducted among patients aged 65 years and using benzodiazepines or related drugs (n = 38) in acute wards (n = 2) of Pori City Hospital in 2004. Elderly patients reported that the package leaflet was the main source of medicines information on benefits and adverse drug reactions relating to medicines they used. The physician was reported as a second source after the package leaflet. More than 50 percent of the elderly (n = 20) had not received information about the benefits or adverse drug reactions of benzodiazepines from their health care providers or relatives. The information received had merely focused on benefits of drug than adverse drug reactions. Most commonly the elderly (61 %, n = 23) knew, that the use of benzodiazepines can cause drug dependence. Least commonly, they were aware that benzodiazepines can cause muscular weakness, depression and falling over. Eight elderly were not aware of any asked adverse drug reactions and nearly two thirds of the patients (63 %, n = 24) knew less than four adverse drug reactions out of eleven. The results indicate that elderly patients are not well aware of the effects of benzodiazepines and related drugs they use. Additionally, they may more often receive information from the package leaflet than health care professionals. Physicians and other health care professionals should pay more attention to counseling elderly patients especially about the benefits and adverse drug reactions of benzodiazepines and related drugs.

Current therapies for depression have limitations in efficacy and delayed onset of action. Rapid-acting antidepressants like ketamine, an N-methyl-D-aspartate receptor (NMDA-R) antagonist, have gathered attention as an improved treatment option. However, the neurobiological mechanism underlying their antidepressant effect remains uncertain. Integral mechanisms of action seem to be alterations in synaptic plasticity, global cortical excitation, and repair of neuronal dysfunctions prevalent in the pathophysiology of depression. Emerging evidence does suggest that antidepressant drugs act by facilitating brain derived neurotrophic factor (BDNF) mediated tropomyosin receptor kinase B (TrkB) signaling. Interestingly, rapid-acting antidepressants seem to increase TrkB-associated signaling after their acute pharmacological effect has dissipated, and when animals become sedated and show various physiological changes associated with deep sleep (e.g., slow wave EEG activity, SWA). Indeed, recently a close relationship between sedation and molecular signaling implicated in antidepressant effects has been discovered. The aim of this study was to explore the relationship between sedation and molecular signaling associated with antidepressant effect. This was carried out by assessing the localization of TrkB-associated phosphorylation signaling in the adult male mice medial prefrontal cortex (mPFC) using dexmedetomidine, a sedative. Key signaling molecules such as ribosomal protein S6 kinase (p70S6K), ribosomal protein S6 (rpS6), glycogen synthase kinase 3 (GSK3), mitogen activated protein kinases (MAPKs) and immediate early gene c-Fos, were examined through immunohistochemical (IHC) analysis. Two separate experiments were conducted using naïve adult 8-13-week-old (n=8 and n=10) male C57BL/6JRccHs mice. In the experiments mice were injected intraperitoneally with either dexmedetomidine (0,05 mg/kg, Dexdomitor®), or saline followed by a 30-minute recovery period whereafter mice were euthanized. In the first experiment, medial prefrontal cortex samples were collected immediately post decapitation for western blot (WB) analysis. The results showed that dexmedetomidine significantly activated TrkB-associated signaling in brain homogenates, consistent with expectations. In the second experiment, mice were perfused with 4% paraformaldehyde (PFA) before brain collection for IHC analysis. However in this experimental setting, no significant difference in the localization of TrkB-associated signaling induced by dexmedetomidine was observed compared to saline. Although, no significant results for signal localization were observed, the results provide insights into the neurobiological effect of sedation induced TrkB-signaling. Further research factoring in limitations is needed to uncover the involvement of physiological states in antidepressant mechanisms.

Organic Anion Transporting Polypeptide 2B1 (OATP2B1) is an influx transporter expressed widely throughout the body in tissues such as intestine, liver, brain, placenta and skeletal muscle. Since many clinically used drugs are transported by OATP2B1, changes in the function of the transporter due to genetic polymorphism could lead to altered pharmacokinetics or -dynamics of OATP2B1 substrate drugs. The aim of this Master’s thesis was to create and optimize a cellular uptake assay to study the function of OATP2B1. Furthermore, the aim was to study the effects of six naturally occurring nonsynonymous single nucleotide variants on OATP2B1 transport function in vitro. With site-directed mutagenesis, single nucleotide changes were introduced into the gene coding for OATP2B1. OATP2B1 variants were expressed in human derived HEK293 cell line using baculovirus expression system. A cellular uptake assay with estrone-3-sulfate and a fluorescent probe 4’, 5’-dibromofluorescein (DBF) as substrates was set up and optimized. With the assay, OATP2B1-mediated uptake of variants was compared to the transport activity of OATP2B1 wild type. Amino acid changes Ser486Phe and Cys520Ser impaired OATP2B1 transport function severely. In addition, variant Thr318Ile transported DBF and estrone-3-sulfate less efficiently compared to OATP2B1 wild type, but Arg312Gln, Thr392Ile and Ser532Arg transport function was not affected. A method to study OATP2B1 function was created successfully. According to the results, single amino acid changes in OATP2B1 can impair OATP2B1 function. The results and method can be utilized to understand findings from pharmacogenetic studies in vivo, and to predict consequences of especially rare variants, which can be difficult to detect in small sample populations in clinical studies. However, further studies on the expression level and cellular localization of OATP2B1 variants are needed to fully characterize the impact of the variants studied.

Twin screw granulation (TSG) has gained considerable interest as a continuous wet granulation method in the pharmaceutical industry and has been studied the most. However, there is still lack of understanding how continuous granulation affects the material compaction behavior even though it has been noticed in several dry and batch wet granulation studies that the granulation process has an influence on the final tablet strength. Thus, studies on the material compactability and tabletability after continuous wet granulation are relevant for the overall understanding of twin screw granulation process and its effect on material behavior in tableting. Hence, the main objective of this study was to investigate the influence of continuous twin screw granulation on the compactability and tabletability of commonly used excipients. Additionally, the impact of binder on the compaction behavior of materials was examined. Furthermore, the suitability of two "loss in compressibility" models i.e. the Unified Compaction Curve (UCC) model and a porosity model to predict the loss in tablet strength after twin screw granulation and for the materials used was assessed. Earlier, the models have been applied to dry and batch wet granulations only. Full factorial design of three variables (binder type, binder addition method and the number of kneading elements) with two levels was conducted for the ConsiGma1 twin screw granulation of formulations containing microcrystalline cellulose (MCC), mannitol or anhydrous dicalcium phosphate (DCPA) as the main excipient and polyvinylpyrrolidone (PVP) or hydroxypropyl cellulose (HPC) as binder. Magnesium stearate was added as lubricant after granulation prior to tableting. In addition to the full factorial design, granulation with PVP, dry binder addition and four kneading elements was repeated for each main excipient. In total this made 27 experiments. The granules were dried and milled after granulation and all the batches were tableted. Additionally, all the formulations were direct compressed in order to be able to detect the change in compactability and tabletability after granulation. Torque of the granulation was determined as well as bulk density and particle size distribution of the granules. Additionally, the tensile strength and porosity of the tablets were analysed. Tabletability and compactability were determined based on the compaction pressure and the obtained tensile strength and porosity values of the tablets. Furthermore, parameters (PWG, TWG and εWG) describing the loss in compressibility models were calculated. MCC experienced loss in compactability and tabletability after twin screw granulation due to hornification effect. On the other hand, the compaction behavior of mannitol improved due to the formation of porous granules. The compactability of DCPA decreased and the tabletability increased. However, the change was only moderate presumably due to brittle nature of DCPA. Additionally, the binder type had an effect of the compaction behavior of the materials, PVP producing stronger tablets compared with the less hydrophilic HPC. However, the binder addition method played only a small role in modifying the compaction behavior. The UCC model was applicable to MCC as loss in tabletability was detected. Thus, the model can be used to predict tablet tensile strength when MCC is granulated with twin screw granulator. Additionally, the UCC model can be used to design the granulation process to achieve a target tensile strength based on small scale preliminary studies thus reducing the resources needed for case-studies. However, the UCC model was not feasible to mannitol and DCPA because they experienced improvement in tabletability after twin screw granulation. The porosity model was applicable to MCC and DCPA but not to mannitol as it showed improvement in compactability. The porosity model described the loss in compactability of MCC only moderately due to lack of tensile strength data points and the linearity of the tensile strength-porosity relationship. However, the model described well the loss in compactability of DCPA at tablet porosities achieved with compaction pressures used in industry. As a conclusion, the results demonstrate that twin screw granulation can have a significant impact on the final tablet strength and that the compaction behavior of the formulation can change either way depending on the used materials. Furthermore, the small influence of the binder addition method on the tablet strength indicates that the time consuming binder dissolving process step can be excluded from the tablet production chain enabling continuous manufacturing with twin screw granulation.

The aim of this master`s thesis was to investigate the accuracy of in silico inhalation model to predict pharmacokinetics of orally inhaled products. In literature review special features of the inhalation medication and current statements of medicinal regulatory agencies about bioequivalence (BE) of inhaled products are discussed. The ability of generalized pharmacokinetic BE studies to replace the traditional efficacy studies is a major question in the regulatory agencies. Also the usefulness of published in vitro - in vivo correlations (IVIVC) as an aid for inhaled product development in pharmaceutical industry is considered. Furthermore the most commonly used in silico lung deposition models and their properties are presented. In the experimental part a generic in silico inhalation model was constructed using a proper software and Orion Oyj`s in vitro and in vivo research materials on certain dry powder inhaler (DPI) products. Based on in vitro knowledge the aim of modeling was to predict the pharmacokinetic behavior of a therapeutic drug used in inhaled products. Also the applicability as a tool in clinical study design of inhaled products was estimated. Inhalation model consisted of two separate modeling parts utilizing primary in vitro characterization results of DPI products. Lung deposition of products was predicted with the ARLA (The Aerosol Research Laboratory of Alberta) respiratory deposition calculator available to the public while drugspecific pharmacokinetics was simulated using constructed Stella model (isee systems). ARLA lung deposition model takes into account several factors affecting the final lung dose of medical aerosol. Those include aerosol formulation and the dimensions of the device, as well as breathing conditions and inhalation mode. A rough sensitivity analysis was carried out with ARLA considering the effect of these factors on predicted lung deposition fractions. The predicted plasma concentration profiles, Cmax and AUCt values of the model drug were markedly lower than the experimental values. ARLA deposition model predicted moderately the order of systemic drug exposure obtained with different DPI products. The inhalation model built in the experimental part needs to be refined using more comprehensive and trustable source and reference material. The role of clinical BE studies in the marketing approval of generic inhalation product will be important because currently in silico predictions are still under development.

Drug-induced liver injury (DILI) is a relatively rare hepatic condition that can be classified as predictable and unpredictable. However, DILI is a primary reason for drug withdrawals, post-marketing warnings, and restrictions of use. DILI is a problem for the drug users but also for the pharmaceutical industry and regulatory bodies. From the perspective of patients' and clinicians', DILI is the major cause of acute liver injury. At present, a major problem predicting DILI in drug discovery is a poor understanding of its mechanisms as well as the complexity of DILI pathogenicity. The main mechanism behind DILI are alterations in bile acid homeostasis, oxidative stress, and mitochondrial dysfunction. More than 50 % of drugs causing DILI are causing mitochondrial impairment. If the normal function of mitochondria is disturbed, the energy production of the cell decreases, and cell function decline leading eventually to the cell death. In this study prediction of mitochondrial toxicity was studied using cryopreserved primary hepatocytes of humans and rats. The aim of the study was to clarify if there are interspecies differences in the prediction of toxicity but also investigate possible differences in the mechanisms behind hepatotoxicity by using three well-known compounds toxic to mitochondria. To determine these differences, total cellular ATP was measured after 2- and 24- hour exposure time to gain information on overall viability and possible adaptive responses. Mitochondrial energy pathways were studied as a real-time monitoring acute exposure of test compounds. Morphology, location, and possible adaptive response of mitochondria were studied using a fluorescent probe and antibody staining combined with high content imaging (HCI). Overall, primary rat hepatocytes were more sensitive to the test compounds than human hepatocytes. Also, there were differences between human hepatocyte batches that may reflect the metabolic differences between hepatocyte donors. Immunolabeling did not bring any additional values compared to the fluorescent probe staining in the study of morphology of mitochondria. Additionally, it was noticed that treatment with paraformaldehyde significantly changed the hepatocyte mitochondria morphology. Overall, more effort is needed to develop image analysis of mitochondria morphology. Finally, studying mitochondrial morphology has proven to be difficult, and this study did not unfortunately reveal any information about the adaptive responses of mitochondria for drug-induced liver injury.

Drug induced liver injury is one of the frequent reasons for the drug removal from the market. During the recent years there has been a pressure to develop more cost efficient, faster and easier ways to investigate drug-induced toxicity in order to recognize hepatotoxic drugs in the earlier phases of drug development. High Content Screening (HCS) instrument is an automated microscope equipped with image analysis software. It makes the image analysis faster and decreases the risk for an error caused by a person by analyzing the images always in the same way. Because the amount of drug and time needed in the analysis are smaller and multiple parameters can be analyzed from the same cells, the method should be more sensitive, effective and cheaper than the conventional assays in cytotoxicity testing. Liver cells are rich in mitochondria and many drugs target their toxicity to hepatocyte mitochondria. Mitochondria produce the majority of the ATP in the cell through oxidative phosphorylation. They maintain biochemical homeostasis in the cell and participate in cell death. Mitochondria is divided into two compartments by inner and outer mitochondrial membranes. The oxidative phosphorylation happens in the inner mitochondrial membrane. A part of the respiratory chain, a protein called cytochrome c, activates caspase cascades when released. This leads to apoptosis. The aim of this study was to implement, optimize and compare mitochondrial toxicity HCS assays in live cells and fixed cells in two cellular models: human HepG2 hepatoma cell line and rat primary hepatocytes. Three different hepato- and mitochondriatoxic drugs (staurosporine, rotenone and tolcapone) were used. Cells were treated with the drugs, incubated with the fluorescent probes and then the images were analyzed using Cellomics ArrayScan VTI reader. Finally the results obtained after optimizing methods were compared to each other and to the results of the conventional cytotoxicity assays, ATP and LDH measurements. After optimization the live cell method and rat primary hepatocytes were selected to be used in the experiments. Staurosporine was the most toxic of the three drugs and caused most damage to the cells most quickly. Rotenone was not that toxic, but the results were more reproducible and thus it would serve as a good positive control in the screening. Tolcapone was the least toxic. So far the conventional analysis of cytotoxicity worked better than the HCS methods. More optimization needs to be done to get the HCS method more sensitive. This was not possible in this study due to time limit.

This study aims to address how easily an individual with no prior inhaler experience can learn to use a dry powder inhaler (DPI) through video education. This is a comparative study of four DPIs (Diskus, Easyhaler, Ellipta and Turbuhaler). Different properties affecting ease of use, patient preference as well as educational videos as a method of providing inhaler instructions were investigated. The study used a triangular methodology. The sample consisted of 31 individuals (24-35 years). All participants were considered inhaler naïve. After watching the video education material for a particular inhaler the participants' demonstrated the use of it. Educational videos for all four inhalers were watched and use of all placebo inhalers was demonstrated in a random order. These demonstrations were videotaped. The demonstrations were thereafter checked against a predefined checklist and all mistakes were recorded. Only 33 % of inhaler demonstrations were completed without the participants making any mistakes that could compromise the efficacy of the inhaled medication in a real-life situation. The frequency of error varied greatly between different types of inhalers. Ellipta proved to be most often used correctly with 55 % demonstrating use without making any mistakes. This was closely followed by Diskus for which 48 % demonstrated correct use. The difference between the average error frequency for Ellipta and Diskus was statistically insignificant. With Easyhaler 19 % percent of participants were able to demonstrate correct use, the corresponding percentage for Turbuhaler was 16 %. When comparing participants' demonstrations for Easyhaler and Turbuhaler, the difference in average error frequency between the devices were not statistically significant. The average frequency of error was lower when using Ellipta in comparison to Easyhaler and Turbuhaler (statistically significant). The same indications were found when comparing average frequency of error for Diskus, to those for Easyhaler and Turbuhaler. Comparing the participants self-reported correct use against the actual numbers it is clear that participants often thought they were using the inhaler correctly when they in fact were not. When asked to rank the inhalers from most preferred to least preferred, Ellipta emerged as a favorite. Turbuhaler received the second highest scores, Diskus the third and Easyhaler was least preferred. However, only the difference between preference scores for Ellipta and Easyhaler was deemed statistically significant. The high frequency of error suggests that even though participants generally considered the inhalers intuitive and easy to use, they would have required more comprehensive inhaler education in order to achieve correct inhaler technique. Further, the results indicate that video demonstrations are not ideal for providing inhaler education for first time inhalers users. The most prominent problem with video education is that it provides no feedback to the user regarding their inhaler technique. This may present real problems as the results of this study show that participants tended to overestimate their own inhaler technique. Patient education plays a central role in asthma care and needs to be given proper attention even though the inhalers might be considered intuitive and easy to operate. Interesting areas for future research include investigating interactive learning videos as a way of improving video education on inhaler technique.

Investigating the role of cell membrane proteins has increased over the last decade, as drugdrug interactions and genetic polymorphisms have been found to cause changes in drug pharmacokinetics and dynamics. In this study the characteristics of the OATP1B1 transporter were reviewed and new in vitro research method to study protein functions was developed. Human Embryonic Kidney cells (HEK) is a human derived mammalian cell-line that is widely used in the study of OATP1B1 transporter. The Sf9 cell line is isolated from Spodoptera frugiperda insect and is one of the standard in vitro tools in a genetic engineering study. In the experimental part of this thesis the goal was to express OATP1B1 transporter in Sf9 and HEK293 cell lines. The wild-type SLCO1B1-gene encoding the OATP1B1 was virulent with baculovirus into the cells by the Bac-to-Bac® Baculovirus Expression System. For expression in the Sf9 cells, the aim of the study was to clone the SLCO1B1-gene into the pFastBac vector. The cloning was not successful in this study although attempts were made for several approaches. The expression of OATP1B1 transporter in HEK293 cells was successful. HEK293 cells expressing OATP1B1 transporter are well suited for the study of the SLCO1B1-gene. The in vitro method developed in this study remains in the research team as a tool to investigate the polymorphisms of the SLCO1B1-gene, the inhibition of the transporter and possible drug interactions.