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Mild traumatic brain injury (TBI) is defined as an injury that disrupts the normal functioning of the brain and is the result of external force to the head. It is the most common type of traumatic head injury, and it is common especially in contact sports and within military personnel. Mild TBI typically causes no clear structural changes to the head, but it can induce persistent clinical symptoms, as well as microscopic pathological changes to the brain that may eventually lead to neurodegeneration and increase the risk for several diseases. Mild TBI is a risk factor for several neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, and chronic traumatic encephalopathy. The primary objective of this study was to develop a repetitive mild TBI mouse model for future research purposes in the field of head trauma and neurodegeneration. The injury was induced as a closed head injury with an electromagnetic impactor. Literature and pilot experiments were used to define the parameters of the impactor required to induce a brain injury of desired severity. The characterization criteria of the mild TBI model considered the criteria used to define human mild TBI, as well as long term effects often reported after repetitive mild TBI: neurodegeneration as tau protein related pathology, neuroinflammation, and memory deficits. The secondary objective of this study was to tentatively test a prolyl oligopeptidase (PREP) inhibitor on the behavioral and histological effects of mild TBI. The functioning of the mild TBI model was studied by histopathological and behavioral assessments. After baseline behavioral assessment and repetitive (1 injury every 24 hours altogether 5 times) mild TBI inductions, the mice were monitored for approximately 3 months, during which several rounds of behavioral tests were performed. Barnes maze and novel object recognition tests were used to assess memory functions, and locomotor activity test was used to assess general locomotor activity. After euthanasia, brain histopathology was performed to study the amount of tau protein and the level of neuroinflammation. Due to the low number of animals in the study, the results are directional and need to be confirmed in subsequent studies. The histopathology showed greater amount of neuroinflammation and tau protein in the brains of injured mice, but statistical evaluations could not be made. Memory functions were slightly worse in the injured mice compared to controls, but significance of the results is unclear. Locomotor activity was not influenced by the mild TBIs. PREP inhibition treatment increased the locomotor activity of the mice, but the significance is unclear. The mild TBI model seems promising and the characterization criteria were partially met. The results of the study need to be verified in subsequent studies with a greater amount of animals. The model developed here can be used to study the involvement of head trauma in neurodegeneration, as well as treatment alternatives to changes caused by mild TBIs. As there currently are no curative treatments to neurodegenerative diseases, research regarding neurodegeneration and its risk factors is highly important.

Cancer immunotherapy refers to therapy strategies that utilise the mechanisms of the immune system to treat cancer patients. The benefits of the approach include the possibility for specific targeting and utilisation of the host immune system. The treatment methods include cancer vaccines, oncolytic viruses (OVs), cell-based immunotherapies and antibodies. The interplay between the cancer and the immune system has been observed crucial for the progress of the cancer and the success of immunotherapies. An immune inflamed tumour microenvironment has been observed beneficial for the success of several therapy methods. Many immunotherapy methods rely on detecting tumour specific antigens that are used to guide the therapy agent to the target site. This strategy poses challenges when considering tumour immune evasion mechanisms, which can cause downregulation of target antigens, and heterogeneity of tumour cells and patients. OVs have the advantage of not requiring predetermined target structures to exert their effect to the tumour cells. They cause direct tumour cell lysis and induce immune responses, and may be modified to express additional genes, including immunostimulatory agents. However, virus-related immunosuppressive mechanisms and a rapid viral clearance may limit their effects. A Western Reserve (WR) Vaccinia virus (VACV) is a highly oncolytic virus strain but the virus has been observed to suppress the function of the cyclic guanosine monophosphate adenosine monophosphate synthase – stimulator of interferon genes (cGAS STING) innate immune pathway which has been shown to have a significant role in anti-tumour immune responses. The aim of this study was to create a WR VACV encoding a dominantly active (D A) STING and to determine whether the virus is capable of activating the cGAS STING pathway. The effects were compared to a corresponding virus vvdd tdTomato that does not have the STING encoding gene. The pathogenicity of viruses was controlled by a double deletion of the thymidine kinase and vaccinia growth factor genes which restricts the virus replication to tumour cells. Transgene fragments were cloned from template plasmids by polymerase chain reactions (PCRs) and joined together in a Gibson Assembly (GA) reaction to form a STING-P2A-eGFP gene insert. The insert was attached to a shuttle vector pSC65-tdTomato by restriction enzyme digestion, ligation and transformation in Escherichia coli. The correct transgene plasmid construct was verified by Sanger sequencing and PCRs. The transgene was inserted to a modified WR VACV vvdd-tdTomato-hDAI by a homologous recombination. The newly created VVdd STING-P2A-eGFP virus was purified by plaque purification. The STING protein expression was studied by an immunocytochemistry (ICC) assay. The immune signalling pathway activation was examined by testing nuclear factor kappa-light chain-enhancer of activated B cells (NF-κB) activation in RAW-Blue cells and dendritic cell activation and maturation in JAWS II cells. The cell viability after iinfection was studied with four cell lines; A549, B16-F10, HEK293 and MB49. The D-A STING expressing virus was produced successfully. The ICC experiment verified the capability of the VVdd STING-P2A eGFP to produce the STING protein in the infected cells. The preliminary findings indicate that the VVdd STING-P2A-eGFP virus activates the NF-κB signalling in the RAW-Blue cells and that the activation is dependent on the STING expression. The activation level is relative to the infection concentration at MOI range 0,001 to 0,1. The findings suggest that the VVdd-STING-eGFP virus can induce innate immune signalling via the STING pathway. The reference virus did not activate the signalling. The in vitro experiments also indicated that the STING virus may induce DC activation and maturation. We observed a trend of CD86 and CD40 expression upregulation on the JAWS II DCs. The effects to the cell viability were inconclusive. More studies should be conducted to verify the results. The effects of the virus should be studied in more advanced cancer models that take into account the complexity of the immune system. These preliminary results indicate the that the VVdd-STING-P2A-eGFP virus could stimulate the immune signalling through the STING pathway.

The potential of extracellular vesicles (EVs) as diagnostic markers and drug delivery vehicles has been studied increasingly in recent years. One of the challenges in this field has been the isolation of EVs from complex biological fluids such as blood. The methods widely used for the isolation process include for example size exclusion chromatography (SEC) and ultracentrifugation (UC). As these methods use size and density of the particle, the have not been efficient enough in isolating EVs from certain particles such as lipoproteins. Due to the challenges related to these methods, other isolation methods have been sought to improve the efficiency of EV isolation. One of these methods is ion-exchange chromatography (IEC). From the two forms of IEC, anion-exchange chromatography has been studied more in EV isolation due to the negative net charge on EV particles. However, in this study the functionality and efficiency of cation-exchange chromatography (CEC) in EV isolation was studied as very little research has been done on this method. In this study, two CEC-resins were studied to define their applicability in EV isolation. A standard strong cation-exchange chromatographic resin SP Sepharose Fast Flow was compared to a strong tentacle-type resin. In addition to this, we studied the possibility to use a magnesium gradient to separate different forms of lipoproteins from EVs through dextran-sulfite precipitation. Tentacle-type CEC-resin was found to be more efficient in capturing EVs compared to the standard-type resin without magnesium. These EVs could then be eluted from the column with sodium chloride. The use of magnesium gradient allowed the separation of apolipoproteins in the samples. Higher concentrations of magnesium also reduced the number of lipoproteins in the samples altogether but resulted in the loss of EVs as well. These results were promising and showed that cation-exchange chromatography can be used in EV isolation. Tentacle-type resin seemed to be most efficient in removing impurities and capturing EVs. While more research is needed before these findings can be applied to clinical use, these results prove that cation-exchange chromatography can be used in EV isolation as a new, efficient and up scalable method.

Diabeetikoiden määrä lisääntyy jatkuvasti. Samalla hoitokulut ovat kasvaneet merkittävästi. Paras tapa hillitä kustannusten kasvua on hoitaa diabetesta mahdollisimman hyvin. Näin voidaan ehkäistä myös diabetekseen liittyvien oheissairauksien syntyä. Diabeteksen hoidossa on tärkeää kiinnittää huomiota hoidon jatkuvuuteen ja potilaan hoitoon sitoutumiseen. Apteekin henkilökunnan asema on noussut yhä keskeisemmäksi diabeetikon hoitoon sitoutumisen edistäjänä. Tämän pro gradu -tutkielman tavoitteena oli selvittää, mikä on apteekin farmaseuttisen henkilökunnan rooli diabetespotilaan hoitoon sitouttamisessa, elämäntapamuutosten toteuttamisessa ja niiden pysyvyyden varmistamisessa. Asiaa tarkasteltiin voimaantumisen teorian näkökulmasta. Tarkoituksena oli selvittää, miten voimaantuminen yksilössä tapahtuu, miten sitä voidaan apteekkineuvonnalla edistää ja mikä on apteekin rooli ulkopuolisena voimaannuttajana. Tämän tutkimuksen aineisto on kerätty Mäntyharjun Havu apteekissa ja se on osa laajempaa tutkimusta, jonka päätavoitteena on kehittää ja testata apteekkeihin soveltuva yksilökeskeinen toimintamalli tyypin 2 diabeteksen hoidon tukemiseen. Toimintamalli perustuu säännöllisiin neuvontatapaamisiin apteekissa. Pro gradu -tutkielmaan analysoitavaksi valittiin tutkimusjoukosta (n=19) ne, joilla tapahtui apteekkiohjelman aikana eniten positiivisia muutoksia yksilötasolla sekä elämäntapamittareilla mitatuissa arvoissa että kliinisissä parametreissa (n=4). Kvaliatiivisessa analyysissä käytettiin sekä deduktiivista että induktiivista lähestymistapaa. Vaikka diabeetikoilla oli tietoa sairaudesta ja elämäntapojen merkityksestä, niin käytännön tasolla jokainen henkilö kaipasi hoitoon ja erityisesti muutosten toteuttamiseen tukea ulkopuoliselta taholta. Apteekin rooli ulkopuolisena voimaannuttajana koettiin erityisen keskeiseksi. Tapaamiset loivat oikeanlaisen ympäristön ja ilmapiirin elämäntapamuutosten toteuttamiseen ja voimaantumisprosessin etenemiseen. Voimaantuminen ruokavaliomuutoksiin oli koko intervention aikana melko nousujohteinen prosessi. Sen sijaan voimaantuminen liikunnalliseen elämäntapaan oli aaltoilevaa. Apteekkitapaamiset sosiaalisena tapahtumana paransivat asiakkaan hoitoon sitoutumista. Asiakas koki, että häntä kohdellaan yksilönä kokonaisvaltaisesti. Voimaantuakseen yksilö tarvitsi aikaa. Vuoden mittaisen intervention aikana voitiin saavuttaa pysyviä muutoksia elämäntapoihin, mikäli yksilöllä itsellään oli halu ja motivaatio sitoutua tukiohjelmaan. Tämä tutkimus osoitti, että tämänkaltaista apteekkiohjelmaa tarvitaan. Nykyisessä kiireyhteiskunnassa ihmiset arvostavat, jos jollakin on aikaa paneutua yksilöön itseensä ja hänen sairautensa hoitoon kokonaisvaltaisesti.

Hepatotoxicity is an undesired feature of many drugs and is one of the main reasons for attrition during the drug development process. Although an in vitro model can never totally correspond to or replace a whole organism, a reliable in vitro model for liver toxicity screening would help to detect liver toxicity earlier in the development process. Effective and early in vitro screening would reduce the need of animal subjects and clinical trials and thus would be both ethically more acceptable and more cost-effective. Currently mostly used models for liver metabolism and toxicity studies are primary hepatocytes, hepatic cell lines and animal models. However, these models have many drawbacks and are not considered reliable. Human embryonic stem cells (hESCs) are pluripotent cells that can be differentiated into many specialized cell types including hepatocytes. They are also self-renewable and thus represent an unlimited and promising source of hepatocytes to be used as a tool in in vitro liver toxicity testing of drug candidates. The aim of this study was to produce hepatocytes from hESCs via multiple steps following the in vivo pathway of developing hepatocytes: first hESCs were differentiated into definitive endoderm cells, after which they were differentiated into hepatic progenitor cells. Finally, hepatocyte-like cells (HLCs) were induced from the progenitor cells. Our specific interest was the use of hepatic cell derived acellular matrix as a differentiation basis for hepatic progenitors and hepatocytes. We also studied the effect of Matrigel overlay on the hepatic differentiation. Differentiation method without the Matrigel overlay was promising. HLCs showed correct hepatocyte-like morphology and expressed hepatocyte markers such as albumin, α-antitrypsin, CYP3A4 and HNF4α both on mRNA and protein level shown by qPCR and flow cytometry and immunofluorescence staining, respectively. Accordingly, the expression of stem cells marker SSEA-3 showed a tendency to decrease as the differentiation proceeded. HLCs also functionally resembled hepatocytes shown by albumin production. However, we could not detect other hepatocyte functions such as urea production or CYP activity. With Matrigel overlay, the hepatocyte-like morphology of the cells was lost, no albumin production was shown and the expression of several hepatocyte markers was lower than in the experiment done without the Matrigel overlay. Thus, Matrigel overlay was shown to be unbeneficial for hepatocyte differentiation. In conclusion, we showed that differentiation of hESCs on the acellular matrix with specific growth factors and without the Matrigel overlay seems promising as a method to produce HLCs. This preliminary study serves as a basis for future studies, in which the differentiation method should still be further studied and developed to yield functional HLCs of uniform quality.

Posterior eye segment diseases, such as age-related macular degeneration, are leading causes of preventable visual impairment in the developed countries. Direct intravitreal injections are currently routinely used to deliver therapeutic agents most efficiently to posterior eye segment. Regular injections can however cause ocular complications and some drugs may also be toxic to ocular tissues at high local concentrations of free drug. Different nano-sized particulate systems have been extensively studied as possible drug delivery systems for intravitreal administration offering sustained, local drug action with controlled release. The vitreous gel can form a barrier for diffusion of particles due to its macromolecular structure and composition. Furthermore, ageing and different disease states cause changes in the vitreous structure possibly resulting in shift in the intravitreal movement of particulate systems. In the literature part of this Master's thesis ocular drug delivery is reviewed with main focus on drug targeting in the posterior eye segment. In the experimental work liposomes with different lipid compositions and surface charges were prepared as model particulate systems to evaluate the intravitreal diffusion of nanoparticles with confocal microscope. Furthermore, the influence of aging on the intravitreal diffusion was modeled by enzymatic degradation of the vitreous gel structure. It is discovered that vitreous gel hinders the movement of nanoparticles. Level of hindrance depends on particle's characteristics. 100-200 nm anionic particles move quite freely in the negatively charged vitreous gel. Similarly sized cationic particles are immobile in the vitreous due to electrostatic interactions between surface of the cationic particle and anionic glycosaminoglycans in the vitreous. 1 µm anionic and cationic particles are sterically trapped inside the vitreous meshwork created by the 3-dimensional biopolymer network of the vitreal macromolecules. Vitreous liquefaction increases the diffusion rate of nanoparticles but the clinical impact on ocular pharmacokinetics needs further research.

Neurodegenerative diseases and neuronal injury after trauma are common causes of neuronal loss. Adult brain has only a limited regenerative capability to replace the lost neurons caused by several distinct brain diseases. Direct reprogramming of brain resident cells into neurons could provide a promising strategy for efficiently replacing non-functional neurons. To date, the focus has been put largely on astrocyte-to-neuron reprogramming despite the relatively low yield of newly generated neurons reported in vivo. According to our hypothesis oligodendrocytes possess a more diverge transcriptomic profile when compared to neurons and astrocytes thus allowing better cell-specific targeting of reprogramming. Here, we establish the molecular tools for direct neuronal reprogramming of human oligodendrocytes to neurons. We investigate whether the expression of a known neural fate specification factor under selected oligodendrocyte-specific promoters is sufficient to induce oligodendrocyte-to-neuron transformation. Furthermore, we test the established tools in vitro using an immortalized human oligodendrocyte cell line. Our preliminary data shows that the human ERBB3 promoter and a single transcription factor transfected cells express doublecortin (DCX), an early marker of neuronal identity. Only recently, the direct in vitro reprogramming of human oligodendrocyte precursor cells into functional neurons has been reported. The direct reprogramming of oligodendrocytes into neurons provides an exciting alternative of neuronal replacement for astrocyte-to-neuron reprogramming. Overall, the field of direct reprogramming offers interesting possibilities for regenerative medicine providing a method for the production of newly generated disease and patient-specific cells.

New drugs against malaria are required, as millions of people are still affected yearly by this deadly disease. The development of drug resistance to current antimalarials is an ongoing process. Membrane-bound pyrophosphatases (mPPases) are potential new drug targets against malaria and other protozoan diseases. mPPases play a crucial role in the survival of the malaria parasite, they couple the energy released from the hydrolysis of pyrophosphate into the transport of protons or ions against an electrochemical gradient. The aim of this study was to identify potential mPPase inhibitors through a docking-based virtual screen of the Tres Cantos Antimalarial Compound Set, which consists of over 13500 malaria-active compounds. The virtual screen against a Thermotoga maritima mPPase protein structure identified a 2,4-diamino-1,6-dihydrotriazine among the top-ranking scaffolds. Four compounds found among the docking results containing this scaffold were synthesised: three with a halophenyl substituent, and one with a hydroxyl substituent. The compounds in their hydrochloride salt forms were synthesised using a three-component method for the synthesis of 2,4-diamino-1,6-dihydrotriazines. The compounds were also freed from the hydrochloride salts into their corresponding molecular forms. The structural characterisation of the compounds, especially the molecular forms, presented challenges. The docking results were also searched to identify compounds containing previously identified mPPase-active substructures. From the docking results, several other interesting compounds were identified in addition to the synthesised compounds. The knowledge and results obtained from this study can be used as openings for potential future docking and synthesis projects in the development of mPPase inhibitors. The activity of the compounds synthesised in the project remains to be evaluated in subsequent investigations.

Literature review: The plasma membrane DA transporter (DAT) belongs to the family of Na+/ClÙÄÉ≠ dependent neurotransmitter transporters. DAT is the primary mechanism for clearance of dopamine from the extracellular space and transporting it back to the presynaptic nerve terminals. There's a great interest in the DAT and its regulation as its substrate, dopamine, mediates a wide array of physiological functions e.g. locomotor activity, cognition and the control of motivated behaviors. With selective transport DAT limits the intensity and the duration of dopaminergic signal. Its function is regulated by several kinases, phosphatase and protein-protein interactions. The altered expression of DAT may be related to several neurological diseases such as Parkinson's disease, addiction and ADHD. To study DAT's function, several genetically modified mouse lines including DAT knockout mice, DAT knockdown mice and DAT knock in mice with elevated DAT levels have been generated. Experimental part: Glial cell line-derived neurotrophic factor (GDNF) plays important role in the survival and function of dopaminergic neurons, learning, memory and synaptic plasticity. More recently, several studies have shown that GDNF can also negatively regulate the actions of abused drugs. The aim of this study was to investigate GDNF's role and mechanism of action in plasticity and function of the dopaminergic neurons projecting to striatum. For that purpose, we used in vivo microdialysis in freely moving mice. We chose two different mouse lines: MEN2B mice with constitutive active Ret-signaling and elevated striatal dopamine concentrations, and GDND-cKO mice that lack GDND in the central nervous system. Microdialysis guide cannula was implanted in the dorsal striatum in the stereotaxic surgery and the mice were allowed to recover for 5-7 days. The concentrations of dopamine and its metabolites DOPAC and HVA and also 5-HIAA were determined from the samples by highperformance liquid chromatography. Microdialysis was performed twice for every mouse on days 1 and 4. Between microdialysis days, the mice were given amphetamine 1 mg/kg i.p. on days 2 and 3. In the microdialysis experiment, the mice received amphetamine stimulation (100 µM/60 min) via microdialysis probe. The placements of microdialysis probes were verified from fixed brain sections after the experiments. Amphetamine increased the dopamine output in both mouse lines, but there were no statistically significant differences in striatal dopamine concentrations between genotypes neither after acute nor chronic administration. However, there was a difference between the dopamine outputs in days 1 and 4 in both MEN2B and GDNF-cKO mice: The striatal dopamine concentrations were significantly lower on the second microdialysis day. This may be a sing from tolerance to the drug. However, without more research, it is not possible, by this experiment, to draw direct conclusions of GDNF's role in addiction and in plasticity in striatum. It is possible that the differences between genotypes are too small to be seen with microdialysis. Development of compensatory mechanisms in mice cannot be ruled out either. Effects may also vary between different brain areas.

Drug shortages have become a global issue and reasons for drug shortages are several and multifactorial. Definition of drug shortages is not unambiguous. However, in literature are numerous different suggestions to determine the phenomenon of drug shortages. This study provides more focused information on drug shortages and the reasons behind them. The study was performed in cooperation with Orion Corporation. The aim of this study was to explore the in-depth reasons behind medicine shortages from the perspective of one European pharmaceutical company with special focus on Finland, Germany, the United Kingdom and Sweden. Interviews of the company employees were used to achieve this aim and build a few case studies. Further the aim was to investigate in-depth reasons for drug shortages using data from case studies. Case studies were provided by Orion since this enabled use of unpublished information compare the case studies with relevant legal and regulatory measures in the European pharmaceutical framework which influence drug shortages. Reviewing available data from literature and from EUDRA GMDP database for drug shortages and investigate if the data is detailed enough to understand in-depth reasons for drug shortages. Based on the interview results the most common reasons behind drug shortages in Europe are mainly pharmaceutical market structure 38%. It contains many different factors, such as small stock size, local and foreign manufacturing issues, logistics and distribution issues, changes in demand and regulatory issues. However, the manufacturing (33%) or regulatory (29%) reasons are almost as numerous as pharmaceutical market structure issues. Pharmaceutical market structure issues include most common reasons which are categorized in supply-related and demand-related reasons. According to this study supply-related reasons are more common (73%) than demand-related reasons (27%). Some reasons behind drug shortages overlap and often cause a domino effect, whilst other are unique or stand alone, like reasons resulting from natural disasters. The results of this study seem generalizable because the EUDRA GDMP database shows same results and case studies illustrative same reasons behind drug shortages. This study provides more focused information on drug shortages and the reasons behind them from the perspective of pharmaceutical company and authorities.