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  • Miettinen, Ilkka (2016)
    Multi-drug tolerance is a phenomenon, in which microorganisms normally susceptible to an antimicrobial agent are able to withstand a treatment via phenotypic alteration. The tolerance is conveyed by a microbial subpopulation that is in a non-replicative and metabolically inactive state also known as persistence. Through this kind of dormancy, the subpopulation may survive an otherwise appropriate course of antimicrobials, since the majority of the drugs target cellular division or metabolism. Upon the reduction of the surrounding antimicrobial concentration the multi-drug tolerant cells - persisters - become resuscitated thus allowing repopulation. As opposed to the more widely acknowledged challenge of antimicrobial resistance, the offspring of the specialist survivor cells are genetically identical to the susceptible majority. Persisters are especially abundant in biofilms, a microbial lifestyle characterized by aggregated microcolonies that are covered in a self-produced slimy matrix known as extracellular polymeric substance (EPS). Partly owning to this protective matrix, biofilms are inherently somewhat tolerant to antimicrobial chemotherapy. Moreover, microbes confined in a biofilm are additionally protected against the components of the host immune system. Conversely, it is assumed that persisters in planktonic, i.e. freely floating state, are easily cleared out by white blood cells. Combined, the immune evasive properties of biofilms and the remarkable multi-drug tolerance of persisters give rise to recalcitrant infections that are immensely difficult to eradicate. The described phenomenon constitutes crucially to the major healthcare challenge of chronic, treatment-resistant infections. Tuberculosis, cystic fibrosis lung disorder, bacterial endocarditis and infections related to indwelling medical devices are only a few examples of such problems. Despite the need for antimicrobials with anti-persister efficacy, no such therapeutics is available and very few are being investigated - one important factor being the lack of relevant drug discovery platforms. Therefore, the aim of this study was to develop an anti-persister assay and to carry out a pilot screening of natural product derived bioactive compounds. Based on the notion that persisters are enriched in bacterial cultures that have reached the stationary phase of growth, a persister model was designed using Staphylococcus aureus ATCC 25923 as the test strain. The bacteria were grown in liquid cultures until they reached the stationary phase and subsequent experimentation was carried out to confirm the tolerant state. After the stationary phase persister model was validated, a small pilot screening of natural products was undertaken in the hope of finding novel anti-persister activity. Mitomycin C, a cytotoxic drug with an existing anti-cancer indication was assigned as the positive control compound because of its previously established anti-persister activity. Since it is common for all of the persister-related diseases that the target microorganisms reside within a protective biofilm, an additional assay based on biofilm regrowth was designed to characterize the hit compounds on a more clinically relevant platform. The persister model culture was shown to be tolerant to conventional antibiotics. The re-induction of metabolic activity by diluting into fresh medium recovered the antimicrobial susceptibility expectedly. A total of 4 compounds were identified as anti-persister hits in the pilot screening campaign. Chromomycin A3, dehydroabietic acid, mithramycin A and oleanolic acid were all able to reduce the viable bacterial count in the stationary phase persister model more than 2 logarithmic units at 100 µM. Mithramycin A was the most potent, reducing the viability over 6 log units. The model compound mitomycin C reduced the viable counts 5.49 (± 0.96) logarithmic units. Out of the 4 hits, dehydroabietic acid was selected for the biofilm relapse assay because of its favourable biocompatibility properties. It reduced regrowth for the treated biofilms by 4 logarithmic.
  • Tuomisto, Justiina (2023)
    Children´s medication treatment has many special features that predispose to medication errors, such as dosing of medications according to weight or age and the off-label use of medications. In the medical treatment of children high-alert medicinal substances are used and the incorrect use of which can cause harm to the patient. The aim of this study was to identify medication errors in pediatric patients of parenteral nutrition products (PN) and concentrated electrolytes, which belong to high-alert medicinal substances in different stages of medication management and use process and also to identify the contributing factors behind the errors in order to promote medication safety. The data for the retrospective registry study were made up of HaiPro accident reports (n=528) related to PN, lipids, concentrated electrolytes, solutions affecting electrolyte balance and dialysis fluids made in the period 2018-2020 at the Children`s and Adolescent`s hospital in Helsinki from which the reports related to high-alert medications were identified (n=317). ISMP´s (Institute for Safe Medication Practices) and JCI´s (Joint Comission International) lists of high-alert medications was used to limit the data. The final research material was further limited to reports (n=254) in which the medicinal substance appeared more than ten times in the entire material. The data were analyzed quantitatively to describe the frequencies (n) and percentages (%) of PN and concentrated electrolytes, and qualitativevely to identify the stages of the medication management and use process, types of medication errors and contributing factors. High-alert medications accounted for more than half (n=317/528, 60,0 %) of the entire material of this study. Medication errors (n=378) were identified most during the administration and preparation phase of the medication. In the administration phase, 56,8 % (n=117/206) of errors were identified with PN and the most common error was disturbances in the infusion tubing, wrong infusion rate or wrong dose. With concentrated electrolytes, errors in the administration phase were identified in 50,0 % (n=86/172) of all errors and the most common error was wrong product the patient received, wrong infusion rate and medicine not being administered. In the medication preparation phase, errors were identified in 20,9% (n=43/206) of PN and 30,2% (n=52/172) of concentrated electrolytes. The most common error in the preparation phase was incorrect preparation of medicine with both groups of medicinal substances. Factors related to workload and resources and human factors related to the employee, were most identified as contributing factors (n=753) in both medication groups. Targeting preventive protections, especially in the administration and preparation phases of the medicine is desirable both with PN and concentrated electrolytes. It is also important to plan safeguards comprehensively for the entire mediacation management and use process taking into account the key contributing factors that predispose to medication errors.
  • Juvankoski, Jonna (2023)
    The medication process in palliative care is prone to medication errors and their significant consequences.The complex nature of palliative care medication includes frequent use of parenteral drugs and drug mixtures. Many of the medications used parenterally are considered high-alert medications which carry a significant risk of harm if used in error. By investing in medication safety initiatives, quality of palliative care can be improved, and costs reduced. The aim of this study was to identify the most common compositions of parenteral morphine and oxycodone mixtures administered in patient units providing special level (level B) palliative and hospice care in Helsinki. Identifying the most common compositions enables further researchon standardizing mixtures and centralizing compounding to improve medication safety. This study was conducted as a retrospective medical record review. The data was extracted from the electronic client and patient record system Apotti and consisted of medication administration records of 120 patients receiving special level B palliative and hospice care in Helsinki At-home Hospital and two patient wards in Suursuo Hospital. The data was analyzed with descriptive statistics using Microsoft Excel program. Patient characteristics, including age and ICD-10 diagnosis groups were analyzed. The most common drug combinations used in the mixtures and the combinations with the most variation were identified. Four drug combinations with the most unique compositions were selected for further analysis in which drug concentrations and daily drug doses were analyzed based on continuous infusion rates. 182 drug mixtures including morphine and 147 including oxycodone were identified. A diluent (NaCl 0.9%) was used in 225 mixtures and most often (178/225) the mixtures were diluted into volume of 20 ml. The most frequently used drug combination was comprised of morphine, midazolam, and haloperidol (26.4%), followed by the combination of oxycodone, midazolam, and haloperidol (21.8%). These combinations were also among the four combinations with the most unique compositions with the combination of oxycodone and midazolam and the combination of morphine, midazolam, haloperidol and glycopyrronium. In the four drug combinations with the most unique compositions, the variation was often relatively minor, and the largest variations were observed in opioid components: especially morphine was used in a wide variety of concentrations (2.00–17.91 mg/ml) and daily doses (15–260 mg). Most of the mixtures selected for further review (89/96) were compounded to provide a continuous infusion over a period of four days. In the studied units, mixtures with comparable compositions and features were frequently utilized, suggesting that standardization may be a feasible way to improve medication safety and quality of care in palliative care. As most of the mixtures were administered via PCA, standardization could be particularly advantageous. While it may be possible to standardize and centrally compound mixtures used in this study, more research is needed in several aspects, including physiochemical properties of the mixtures, meeting the clinical requirements in the units, and understanding the underlying factors behind medicine prescribing.
  • Toivonen, Johanna (2012)
    Parkinson's disease is a neurodegenerative disorder where dopaminergic neurons in substantia nigra are gradually destroyed. Less than 10% of Parkinson's disease cases are genetic. For example mutations in α-synuclein, LRRK2-, parkin-, PINK1- and DJ-1 are known to cause Parkinson's disease. There is still no curative treatment for Parkinson's disease. Alpha-synuclein is linked to Parkinson's disease through Lewy bodies. Three point mutations causing Parkinson's disease have been found in a gene coding α-synuclein. Alpha-synuclein has been expressed in Drosophila melanogaster, C. elegans and mouse. Main function of LRRK2-protein is thought to be kinase activity. Mutations in LRRK2-gene are the most common known cause of Parkinson's disease. LRRK has been expressed in Drosophila melanogaster, C. elegans and mouse. LRRK2 knock-out Drosophila melanogaster and mouse have also been studied. Parkin is a neuroprotective protein and its deficiency results in a loss of neurons in substantia nigra. Mutations in Parkin cause 50% of recessive Parkinson's disease. Parkin knock-out Drosophila melanogaster and mouse and Drosophila melanogaster and mouse expressing human Parkin are Parkin animal models. PINK1 is a mitochondrial protein coded by nucleus. DJ-1 is thought to have a part in mitochondria maintenance and protection. Both PINK1- and DJ-1 knock-out Drosophila melanogaster and mouse have been studied. None of the genetic animal models of Parkinson's disease is identical to symptoms and pathology of human Parkinson's disease. The purpose of the experimental part of this thesis was to examine non-drug induced behavioural test and Cerebral dopamine neurotrophic factor (CDNF) in 6-OHDA lesioned rats. CDNF protects and restores dopaminergic neurons. The non-drug induced behavioural tests included in this study were stepping test, cylinder test and staircase test. An old and widely used drug induced test for Parkinson's disease, amphetamine-induced rotation test, has problems that have led to a seek for replacing and complementary test methods. In amphetamine-induced rotation test dopamine agonist is given to a unilaterally 6-OHDA lesioned animal. The agonist causes rotational behaviour that can be measured with designed equipment. The stepping test measures forelimb akinesia in rats. In the experimental setting the rat is moved sideways when it is held only one front paw on a table and adjusting steps are counted. In the cylinder test front paw preference is measured. In the experimental setting the rat is placed in a transparent cylinder and the front paw preference is counted on rears and on ground contacts after a rear. The staircase test measures front paw coordination and function. In the experimental setting the number of sucrose pellets picked up from a double staircase is counted. There were no significant differences between lesioned groups in stepping test, cylinder test or in staircase test. It is possible that the 6-OHDA lesion used in the experiment was not extensive enough. Different non-drug induced behavioural tests supplement each other and they should be combined for the best result. Combining different behavioural tests enables more reliable results and versatile information than the amphetamine-induced rotation test alone.
  • Koljonen, Petri (2012)
    Parkinson's disease is characterized primarily as a bradykinetic disorder with severe nigral cell loss. In addition to motor symptoms, up to 85 % of patients with Parkinson's disease experience pain and in about 60 % of cases pain is related to Parkinson's disease. Most of it is classified as musculoskeletal pain. Bradykinesia and muscle cramps lead to pain by causing malpositions of joints and trunk. Up to 40 % of parkinson patients experience pain caused by dystonia. Neuritic or radicular pain is also related to Parkinson's disease. Less than 10 % of patients have primary central pain. Pain threshold and nociceptive flexon reflex threshold are lower among patients with Parkinson's disease than in healthy subjects. Common comorbidities, namely restless legs syndrome and depression can also exacerbate pain. The pathology of pain in patients is not well understood. It is known that basal ganglia take part in pain perception and modulation. Lesions in basal ganglia can interfere pain perception and cause the exacerbation of pain. The modulation of pain in central nervous system is altered and descending inhibitory tracts are thought to work insufficiently. Levodopa alleviates the pain in about 60 % of patients with Parkinson's disease suffering from pain. Levodopa normalizes dopamine function at least partly in basal ganglia and that way alleviates the pain caused by dysfunction of dopamine tracts. Levodopa relieves motor symptoms and so alleviates the secondary pain caused by muscle cramps and stiffness. Levodopa raises the pain thresholds of patients to normal level. Levodopa may have also a direct analgesic effect via dopamine D2 receptor activation. The mutations of the gene that codes catechol-O-methyltransferase (COMT) change its activity and are related to pain perception. Low COMT activity is related to several functional differences including increased sensitivity to pain and increased response to opioids. Also COMT inhibitors sensitize mice and rats to pain. The mechanism underlying the sensitization is not well understood. We examined the effects of COMT gene disruption and COMT inhibition in acute pain models. In the first part of our study, we examined the effect of COMT inhibitor OR-486 in COMT deficient mice. We tried to clarify wether sensitization to pain is caused by COMT inhibition or some other mechanism. We also tested the effects of endogenous opioids (swim stress) and exogenous opioid (morphine) in COMT deficient mice. In the second part, we tested the effects of an atypical COMT inhibitor CGP 28014 in acute pain models. CGP 28014 does not inhibit COMT in vitro but it inhibits the Omethylation of catecholamines in vivo. The main finding of our study was the sensitization to pain caused by CGP 28014. The result gives support to hypothesis claiming that sensitization to pain is caused by O-methylation of catecholamines. The results of our study are also in line with the theory that low COMT activity is related to pain sensitization and increased response to opioids.
  • Uhari, Johanna (2010)
    Part I: Parkinson's disease is a slowly progressive neurodegenerative disorder in which particularly the dopaminergic neurons of the substantia nigra pars compacta degenerate and die. Current conventional treatment is based on restraining symptoms but it has no effect on the progression of the disease. Gene therapy research has focused on the possibility of restoring the lost brain function by at least two means: substitution of critical enzymes needed for the synthesis of dopamine and slowing down the progression of the disease by supporting the functions of the remaining nigral dopaminergic neurons by neurotrophic factors. The striatal levels of enzymes such as tyrosine hydroxylase, dopadecarboxylase and GTP-CH1 are decreased as the disease progresses. By replacing one or all of the enzymes, dopamine levels in the striatum may be restored to normal and behavioral impairments caused by the disease may be ameliorated especially in the later stages of the disease. The neurotrophic factors glial cell derived neurotrophic factor (GDNF) and neurturin have shown to protect and restore functions of dopaminergic cell somas and terminals as well as improve behavior in animal lesion models. This therapy may be best suited at the early stages of the disease when there are more dopaminergic neurons for neurotrophic factors to reach. Viral vector-mediated gene transfer provides a tool to deliver proteins with complex structures into specific brain locations and provides long-term protein over-expression. Part II: The aim of our study was to investigate the effects of two orally dosed COMT inhibitors entacapone (10 and 30 mg/kg) and tolcapone (10 and 30 mg/kg) with a subsequent administration of a peripheral dopadecarboxylase inhibitor carbidopa (30 mg/kg) and L- dopa (30 mg/kg) on dopamine and its metabolite levels in the dorsal striatum and nucleus accumbens of freely moving rats using dual-probe in vivo microdialysis. Earlier similarly designed studies have only been conducted in the dorsal striatum. We also confirmed the result of earlier ex vivo studies regarding the effects of intraperitoneally dosed tolcapone (30 mg/kg) and entacapone (30 mg/kg) on striatal and hepatic COMT activity. The results obtained from the dorsal striatum were generally in line with earlier studies, where tolcapone tended to increase dopamine and DOPAC levels and decrease HVA levels. Entacapone tended to keep striatal dopamine and HVA levels elevated longer than in controls and also tended to elevate the levels of DOPAC. Surprisingly in the nucleus accumbens, dopamine levels after either dose of entacapone or tolcapone were not elevated. Accumbal DOPAC levels, especially in the tolcapone 30 mg/kg group, were elevated nearly to the same extent as measured in the dorsal striatum. Entacapone 10 mg/kg elevated accumbal HVA levels more than the dose of 30 mg/kg and the effect was more pronounced in the nucleus accumbens than in the dorsal striatum. This suggests that entacapone 30 mg/kg has minor central effects. Also our ex vivo study results obtained from the dorsal striatum suggest that entacapone 30 mg/kg has minor and transient central effects, even though central HVA levels were not suppressed below those of the control group in either brain area in the microdialysis study. Both entacapone and tolcapone suppressed hepatic COMT activity more than striatal COMT activity. Tolcapone was more effective than entacapone in the dorsal striatum. The differences between dopamine and its metabolite levels in the dorsal striatum and nucleus accumbens may be due to different properties of the two brain areas.
  • Helminen, Heidi (2017)
    Obesity is considered one of the major public health challenges. One way to control obesity is to regulate appetite. Because brain is the primary regulative unit responsible for food intake, the research in this field has now been allocated especially to the central nervous system. The aim of this thesis was to clarify the role of cholinergic projections from pedunculopontine tegmentum (PPT) to lateral hypothalamus (LH) in food intake. In this study, DREADD-technology (designed receptors exclusively activated by designer drugs) based on chemogenetics was utilized with a gene manipulated mouse strain. For the experimental part of this work the mice were divided in three separate groups: one transducted with an activating DREADD-receptor (hM3Dq), one transducted with an inhibiting DREADD-receptor (hM4Di) and one transducted only with a fluorescent protein called m-Cherry. The last group was also defined as a control group of this study. In addition, the gene which coded m-Cherry fluorescent protein was transducted together with hM3Dq- and hM4Di-receptor genes for the first two groups to be able to examine the receptor expression later. At the baseline level, no differences were observed in food intake between the three study groups. The food intake did not differ between the groups while clozapine-N-oxide (CNO), a selective DREADD-receptor ligand, was administered straight into the LH area (0,03 µg/injection) with or without fasting of the animals. While administrating CNO to the mice intraperitoneally (1 mg/kg), the hM3Dq-group mice were observed to consume more food compared to the hM4Di-group or the control group. This difference was detected while food consumption was examined cumulatively during total four measuring hours. When the animals were fasted before the intraperitoneal administration test, however no differences were found between the study groups regarding food intake. As a conclusion of this study, cholinergic projections from pedunculopontine tegmentum (PPT) to lateral hypothalamus (LH) were not regulating food intake in mice. However, the cholinergic cells in PPT and some of their axons might be involved in the regulation of food intake while the food consumption is studied continuously and long-term. More studies are required to better define the role of the cholinergic projections from pedunculopontine tegmentum (PPT) to lateral hypothalamus (LH) in food intake.
  • Honkasalo, Oona (2018)
    Cancer immunotherapies aim to target the immune defence mechanisms of the body specifically and efficiently against the tumour tissue. Cancer vaccines and oncolytic viruses are forms of active immunotherapies, which require patients having a properly functioning immune system. The vaccines are based on the administration of tumour antigens into the body to which the immune system reacts. However, often the response is not robust enough. The oncolytic viruses in turn kill the cancer cells which causes the release of antigens from the tumour tissue. Viruses usually elicit a strong immune response but sometimes it is targeted too much against the virus instead of the tumour. Oncolytic vaccine is a composition of an oncolytic virus and a cancer vaccine. Tumour antigens can be coded to the genome of the virus therefore, when the virus invades tumour cells they start to produce the antigens. Eventually the cancer cells are also destroyed due to viral replication. The antigens can be tumour-associated that is, they are expressed in healthy tissues too. Their usage is not always efficient which is why an interest towards utilizing tumour-specific antigens has been increased. Considering the expression of antigens, tumour tissue is very heterogenous and distinctive between patients. Hence, utilizing mutated patient unique neoantigens would enable the development of personalized tumour-specific oncolytic vaccines. Genetic modification of viruses is complicated thus, an easier way to insert the neoantigens to the virus has been invented. The developed oncolytic vaccine platform is called PeptiENV, and it is designed to use with enveloped viruses. The idea is to fuse tumour-specific antigens onto the envelope of the virus and eliminate the need of gene insertion. The aim of this study is to investigate in vivo the efficacy of PeptiENV in preventing tumour growth and eliciting a tumour-specific immune response. An object is also to observe survival times of the treated animals. Furthermore, the preservation of infectivity is studied in vitro. The research was executed with two potential oncolytic viruses, vaccinia virus (VACV) and herpes simplex virus type 1 (HSV-1). The PeptiENV complex was formed by using an artificial tumour antigen, ovalbumin epitope SIINFEKL, which was attached to the viral envelope with cell penetrating peptide (CPP) or cholesterol anchor. The preservation of infectivity was examined by measuring cell viability of PeptiENV infected cells. Animal experiments instead were performed with a mouse melanoma model created with B16-OVA cells, which express ovalbumin and therefore the antigen epitope SIINFEKL. PeptiENV was compared to control treatments which were virus, SIINFEKL peptide and complexation medium only. Treatments were administered as intratumoural injections. Tumour growth was followed by measuring the size of implanted tumours every other day. With flow cytometry, tumour-specific immune response was assessed by acquiring the relative amount of SIINFEKL-specific CD8+ T cells in the tumour tissue. Euthanizing dates were registered in order to observe the survival of the mice. According to the in vitro results, conjugation of peptides to the virus does not affect infectivity. In addition, the in vivo studies show that PeptiENV VACV CPP prevents tumour growth the most. Difference in tumour growth between PeptiENV VACV CPP and control treatments is significant. Mice injected with the same treatment also lived considerably longer than mice injected with virus, peptide or medium only. Also, PeptiENV HSV-1 hinders tumour growth distinctly more than virus only and slightly more than SIINFEKL only, but unfortunately it did not have an evident impact on the survival time. In both experiments, the PeptiENV treatment elicits the largest proportional amount of SIINFEKL-specific CD8+ T cells. In other words, PeptiENV engenders a tumour-specific immune response. In the PeptiENV VACV study the difference to control treatments is clearer than in the PeptiENV HSV-1 study. At present, the PeptiENV platforms performs better with VACV than HSV-1. With further investigations however, the results can be verified and improved. All in all, the results are encouraging. The PeptiENV platform shows great promise for being a part of personalized cancer immunotherapy developments in the future.
  • Luoma, Maaria (2018)
    Inappropriate polypharmacy refers to a situation where more than appropriate amount of medicines are used by a patient. Aged people with multiple morbidities and medications use a lot of health care services and are thus especially vulnerable to iatrogenesis, the health hazards resulting from the acts of a health care system. As a part of normal ageing, geriatric syndromes (e.g. falls, delirium and urinary incontinence) are clinical conditions and symptoms crossing several organ systems and they cannot be connected to a certain individual disease. Geriatric syndromes complicate recognition of adverse drug reactions on aged. This increases the risk of prescribing cascade, where medicines are prescribed to treat adverse drug reactions caused by another medicine. In this master´s thesis the root causes for inappropriate polypharmacy and drug-related problems (DRP) with home-dwelling aged were researched retrospectively from the viewpoint of risk management. Research method was based on root cause analysis (RCA) that was simplified suitable for this research. Research material was based on an intervention research conducted in 2015– 2017 on home-dwelling aged receiving regular home care from the City of Lohja, Finland. In the intervention research, a coordinated community-based medication management model for home-dwelling aged in primary care was developed to identify homedwelling aged with clinically significant drug-related problems. As research material, there were five (n=5) patient cases used who received comprehensive medication review (CMR) in the intervention research to solve their drug-related problems. The research material composed of individual patient interviews conducted at patients’ homes as a part of their CMR visits. Also, the nurses (n=3) of home care and physicians (n=2) from local health centres having participated in the treatment of the home-dwelling aged in question, were interviewed individually. Markings made in the patient records were utilized as well as research material. The interviews of the nurses and physicians were recorded, transcribed and analysed with inductive content analysis considering principles of root cause analysis. According to the nurses and physicians, central clinically significant medication-related problems with home-dwelling aged are various prescribing care parties, multiple medications, the increased use of over-the-counter (OTC) medicines and natural products, the uncertainty of health care professionals of the medication of a home-dwelling aged as well as the occurrence and medication of pain and sleeping disorders with aged. Other essential problems related to the health care system are various attending physicians, obscurely recorded medication data in patient record system, the use of benzodiazepines and other psychopharmaceuticals and ignored renal function in medicine dose adjustment. Problems related to home-dwelling aged are attachment for medicines, resistance to change and desire to take care of their own medication. In addition, memory disorders and vertigo were mentioned as problems related to the medication of aged. Seven root causes for inappropriate polypharmacy and drug-related problems were observed: lack of health care resources, segmented treatment between various health care parties, varying skills and knowledge of health care professionals, ambiguous division of responsibilities between health care professionals, challenges in communication between different care parties, the heterogeneity of patient record systems and problems related to their use as well as the knowledge, opinions and personal situation of a home-dwelling aged. Based on the research, the medication of home-dwelling aged should be improved by striving for centralizing care in one physician either on private or public health care. Among home care nursing personnel there is a need for additional training on medications and pharmacists should participate in regular medication reviews for home-dwelling aged. Patient record systems and data transmission between them should be improved and medication data should be recorded more precisely. Cooperation and communication between home care and health centre should be developed and the division of responsibilities should be clarified. Participation of the home-dwelling aged and their relatives in the care should be promoted. Furthermore, geriatric expertise should be utilized better in the care of the home-dwelling aged.
  • Pottonen, Riitta-Liisa (2015)
    Medication safety is safety related to the use of medicines. Medication errors are drug treatment related events which can lead to medication safety incidents. Medication process is multi-professional teamwork which contains a risk of medication error on every step. It is important to identify potential safety risks in order to prevent the risk events. Medication errors can occur for example during the transfer of the prescription information in to the medication list. It is important that medication lists are accurate and up to date so that patient's medication therapy is optimal. The aim of this study was to assess whether the primary health care medication lists are up to date, accurate and easy to read. The aim was also to identify what kind of information in medication lists was open to interpretation. In one of the municipalities, the medication lists at home were compared to the medication lists at primary care to see whether both lists had identical information on the medication. The data of this study consisted of 240 medication lists from primary care units in three Finnish municipalities. The lists contained altogether 3062 medications. Most of the lists were printed from the patient information systems. Some of the lists were copied from the home medication lists. All medication lists were systematically reviewed and issues open to interpretation were documented in a structured Microsoft Excel table. The data were transferred to SPSS 20 Program for statistical analysis. Most (73%, n=174) of the medication lists (n=240) were incomplete. One-fifth (n=612) of the medications in use (n=3062) contained missing information on medicines. The total number of discrepancies was 807 (mean 3.4 discrepancies per medication list). The most common discrepancies were related to the time of administration (n=277) and dosages (n=241). Duplicate medications included a lot of confusing information. Discontinued medications were not always clearly marked. In only one of the municipalities the medication lists had a space for marking the indication. There were some differences between home medication lists (n=62) and primary care medication lists. ™ Based on this study medication lists have a lot of discrepancies and ambiguities in their information content. The medication lists do not always accurately tell the patient's current medication. Interpretation of inaccurate medication lists consumes unnecessarily doctors' and nursing staff's time. Inaccurate medication lists are a risk to patient safety. It is also important that the medication lists would be similar in all health care units. Electronic prescriptions, the National Health Archive and medication list developed by Information Management Service of Healthcare are expected to solve at least some of the problems related to medication lists.
  • Suvanto, Satu (2014)
    P-glycoprotein is an ATP-dependent efflux protein expressed in many tissues which participate in absorption, distribution and elimination of drug molecules. It can mediate clinically significant drug-drug interactions. Characteristics of P-gp have been studied widely and crystal structure of mouse P-gp has been successfully determined. P-gp binds its substrates either directly from cell membrane or from cytosol and it has at least three separate binding sites. P-gp has wide selection of substrates from many therapeutical groups. According to the latest computational models, a typical P-gp substrate can be defined with the help of molecule structural factors rather than physicochemical properties. However function of P-gp is very complex which is why drug-drug interactions should be studied for each drug pair separately. In addition expression of P-gp is regulated by nuclear receptors PXR and CAR thus P-gp induction is separate, which also complicates P-gp mediated interactions. P-gp substrates celiprolol, talinolol, aliskiren and fexofenadine have in vivo interactions with P-gp inhibitors or inducers. The objective the experimental work was to study suitability of two in vitro methods, MDCKII-cell permeability assay and MDR1-vesicle transport assay, for predicting in vivo effect of drug-drug interaction. ATP-dependent transport of substrates was determined in membrane vesicles extracted from human P-gp expressing Sf9 cells. Cell assay was used to determine efflux ratio (ER) for all the substrates alone and efflux ratio with P-gp inhibitor itraconazole for the substrates which have reported in vivo interaction with itraconazole. All compounds showed ATP dependent transport in MDR1-vesicles and celiprolol, talinolol and fexofenadine showed ER over 1 in MDCKII-MDR1 cells thus according to vesicle assay and ER-value they are P-gp substrates. However ER of talinolol and fexofenadine was not affected by inhibitor itraconazole, thus the drugs did not fulfil the inhibition criteria of FDA for P-gp substrates. The performing of interaction test was possible failed due lack of pre-incubation of the cells with the inhibitor. Talinolol had the highest ER in thus according to cell experiments talinolol has P-gp dependent transport. Aliskiren ER was not obtained because of the low recovery of the drug but it had clear ATP-dependent transport in the vesicle assay as was expected according to in vivo results. According to in vitro results and in vivo studies celiprolol is a poor P-gp substrate whereas fexofenadine showed P-gp mediated transport both in vitro and in vivo. The results suggest that significance of drug interaction is difficult to predict with the vesicle and the cell assay but they can be used to recognize P-gp substrates.
  • Hurmalainen, Virpi (2021)
    P-glycoprotein is an efflux transporter of the ABC family. It is expressed mainly in tissues that have a role in limiting the absorption and distribution of xenobiotics in the body or their elimination. P-glycoprotein is known to have an important role for example in the blood-brain barrier and in protecting the fetus from xenobiotics in the mother’s blood stream. Genetic polymorphisms in transporter proteins can cause individual differences in the pharmacokinetics of drug substances, which can lead to differences in drug efficacy or side effects. In the ABCB1 gene, which codes for p-glycoprotein, several polymorphisms have been discovered. The frequencies of these polymorphisms vary in different ethnic populations. Previous studies have shown that the effects of these polymorphisms are often substrate-dependent. Since there are several confounding factors usually present in clinical association studies, in vitro studies are needed to clarify the effects of individual polymorphisms. Polymorphisms can be studied in vitro by making intentional mutations to the gene sequence and expressing the variant gene in a suitable cell line. In this study four variant p-glycoprotein genes (c.781A>G, c.1199G>T, c.2005C>T and c.3421T>A) were created by site-directed mutagenesis, and expressed in HEK293 cells using a baculovirus recombinant protein expression method. The effects of the polymorphisms were studied by determining the expression level and the transport acitivity of the variant proteins compared to the wild-type. Western blot was used to determine the expression level and a calcein accumulation assay in HEK293 cells was used to compare the transport activities. Also a membrane vesicle transport assay with n-methyl quinidine was set up and optimized, but the variants were not yet studied with this method during this study. In this study no statistically significant differences were found in the transport activities of any of the four variants compared to the wild-type p-glycoprotein. Also the differences in protein expression level between wild-type and variant proteins were small. However, because of the previously reported substrate dependency of polymorphism effects, it would be beneficial to study the variants with at least one other substrate and one other assay method, and thus the membrane vesicle transport assay would be useful to further compare the transport activities of variant proteins to the wild-type p-glycoprotein.
  • Urpelainen, Katja (2021)
    Cardiomyocyte oxygen deprivation followed by apoptosis and cardiomyocytes being replaced with fibrotic tissue can lead to heart failure. Cardiovascular diseases are the most common cause of death world-wide, contributing to 17.8 million deaths in 2017. Treatments currently available aim to maintain cardiac function but are unable to repair the damage, resulting in a poor prognosis for heart failure. Cardiomyocytes are able to proliferate but the endogenous mechanisms of cardiac repair are insufficient to replace the damaged cardiomyocytes, as only an estimated 0.3-1 % of adult cardiomyocytes are regenerated annually. It is known that before birth and up to seven days after birth mice can maintain ability to regenerate cardiomyocytes even after large damage, but this capability is lost within seven days following birth. After this, cardiomyocytes exit cell cycle and will not re-enter it sufficiently to enable cardiac repair. In adults the growth of heart muscle results mainly from hypertrophic growth meaning that the cells grow in width and length. Cardiomyocyte regeneration is an important therapeutic target to which there are no effective pharmacological therapies available yet. The aim of this study was to investigate the effect of 14 novel compounds on cardiomyocyte viability, phenotype and cell cycle activation. Novel compounds were synthesized at the Faculty of Pharmacy, Division of Pharmaceutical Chemistry and Technology, University of Helsinki in Finland. Initial toxicity and cell viability screening was conducted with lactate dehydrogenase assay (LDH assay) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT assay) using COS-1 cells. Based on these assays tolerable concentrations of compounds were determined. Activity analysis was conducted using human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) and immunocytochemistry staining in conjunction with high-content analysis (HCA). Stress response was measured by imaging and analyzing expression of pro-B-type natriuretic peptide (proBNP) and cell cycle activation was imaged and analyzed by using 5- bromo-2’-deoxyuridine (BrdU) as a marker of active cell cycle. In addition, the DNA content of the cardiomyocytes was measured using 4’,6-diamidino-2-phenylindole (DAPI) staining as well as cardiomyocyte morphology investigated with cardiac troponin T (cTnT) staining. One of the compounds, K6, decreased proBNP expression, which can be considered as a sign of decreased stress response. However, K6 also decreased the number of BrdU positive cardiomyocytes that can be considered as a sign of decreased cell cycle activity. Together these markers indicate that the decreased activity may not be due to a stress response caused by the compound. Another compound, K12, increased proBNP expression in all tested concentrations and it also decreased the number of BrdU positive cardiomyocytes. Together these could be considered as an indication of cardiotoxicity. The rest of the compounds did not exhibit remarkable biological activity or there was too great variance between the results of the independent experiments (n=3) to draw definite conclusions. Compounds for this study were chosen for the sole reason of not been tested for biological effects before. Using a defined compound library or screening a larger number of compounds could deliver more predictable results. Early toxicity and viability screenings were a good approach allowing to define toxic compounds and concentrations before continuing with further studies. Pharmacological therapies to induce cardiac regeneration will continue to be an important area of interest in cardiovascular drug research. Phenotypic screening in conjunction with high-content analysis offers variable and statistically significant data on cardiomyocyte proliferation and stress response. The results of the screening could be improved with careful selections of test molecules based on their structure and biological activity. Early toxicity and viability screening further improve the predictability of results. As a result of this study a compound that would induce cardiomyocyte proliferation was not found, however, one compound that seemed to decrease cardiomyocyte stress response was detected and this compound could be of interest for further studies.
  • Tseloev, Idris (2018)
    An ultra-high-pressure liquid chromatography method was used for simultaneous detection of 25 small peptide hormones and their metabolites in urine after solid-phase extraction. This method is first screening step in anti-doping analysis of urine samples. It should be fast, generic and able to detect any sample that may contain a prohibited substance while avoiding false negatives and reducing false positive results. Detection was achieved using quadrupole time-of-flight mass spectrometry coupled with electrospray ionization source in positive mode. Analytes included growth hormone secretagogues, gonadotropin releasing factors, anti-diuretic hormones and their metabolites which are all covered by the list of prohibited substances of the World Anti-Doping Agency (WADA). The practical part of investigation was done in United Medix Laboratories and the aim of study was to expand current screening method by adding new compounds. Optimal experimental conditions were stablished after investigation of different parameters concerning sample preparation and instrumental analysis. The extraction procedure was done by using weak cation exchange SPE with two washing steps (Milli-Q water and methanol), and elution with 5 % formic acid in methanol. The procedure was validated in terms of recovery, specificity, limits of detection, stability and robustness. Recovery was evaluated with 10 ng/ml concentration of analytes and the rest of validation procedures were done at half of minimum required performance level set by WADA (1 ng/ml). Recoveries ranged from 2,6 to 85 % with LODs from 0,01 to 1,76 ng/ml. The suitability of the method was assessed by analyzing different spiked urine specimens containing target substances.
  • Silén, Sanna-Mari (2012)
    Individually tailored smoking cessation, SC, service provided by community pharmacies is a chargeable special service for customers motivated to quit smoking. The service is based on the PAS service model developed in Great Britain and it has been provided by Finnish community pharmacies since 2006. It includes 4-6 meetings with a specially trained pharmacist, who provides counselling, support, SC plan and follow-up. In this pilot study, the service was investigated from customers' viewpoint, assessing their SC outcomes and experiences. The pilot study was a cooperation project of Division of Social Pharmacy and Association of Finnish Pharmacies. It was a part of a larger SC project co-ordinated by Pulmonary Association Heli and financed by Ministry of Social Affairs and Health. This pilot study assessed the feasibility of the service from customer's viewpoint. It assessed weather the service could increase customers' ability to stay abstinent in different phases of the service. Customers' experiences in relation to SC service and SC itself were also assessed. 14 voluntary pharmacies in different geographical locations in Finland participated in this intervention study and they recruited altogether 36 customers. Before customer recruitment pharmacies received education and introduction of the SC service provided by the Association of Finnish Pharmacies. As part of study protocol, the pharmacies informed local healthcare professionals about the pilot study and asked them to send suitable customers to the service. Pharmacies were paid an expert reward for each customer and they were able to provide SC service to the customers either free or with a low charge. Customers' smoking status and experiences about SC service were assessed with two enquiry forms, which they had filled at the beginning of the service and after three months they had started the service. Their background information was collected with specific background forms during the first meeting and their progress in SC service was investigated by service progress forms. 20 of the 28 customers who returned the first enquiry form and 13 of the 17 customers who returned the second enquiry form were abstinent (55,6 % and 36,1 % of all customers, respectively). All the quitters used some pharmaceutical treatment. Customers who quitted assessed their ability to stay abstinent higher than those who were unable to quit, at the outset and during the service. The customers considered service useful and support of the pharmacist was found important. The customers also considered it significant for pharmacies to provide the SC service. Approximately 32 % of the customers who returned the first enquiry form and 41 % who returned the second enquiry form would pay for the service. They would pay 45 € on average (10-100 €). Multidisciplinary service model was not working as expected, since only a small number of customers were recruited by other healthcare professionals. As a result some of the pharmacies recruited customers also from the pharmacy counter without any contact to other healthcare. 36 % of the 36 customers were abstinent at three months. The control group, planned for the pilot study, failed in recruitment and thus we can only compare our findings to other international studies of the SC service, which have provided similar results. Individually tailored SC service provided by pharmacies is suitable SC support for motivated customers. Customers considered service important and useful, but poor willingness to pay creates challenges for pharmacies to provide this kind of service.
  • Kilpiö, Tommi (2021)
    Plant cell culture can be used for the production of valuable secondary metabolites. Inspired by the previous studies focusing on capsaicinoid production, this study aimed for establishing plant cell cultures of Capsicum chinense to produce capsinoids. Capsinoids are non-pungent capsaicinoid analogues with potential health benefits. Another aim of this study was to determine the α-solanine content in Capsicum plants and cell cultures to ensure that no toxic amounts are formed during the cell culture. Cell cultures of non-pungent Capsicum chinense cultivars, Trinidad Pimento and Aji Dulce strain 2, were established, and the cultures were fed with intermediates, vanillin and vanillyl alcohol, to enhance the production. In addition, cell cultures of extremely pungent Trinidad Scorpion cultivar were established and they were fed with vanillyl alcohol to study if this would result in formation of capsinoids instead of capsaicinoids. A high-performance liquid chromatography (HPLC) method with UV detection was validated for determining the capsiate contents of the cell culture samples and fruit samples for comparison. To analyze the α-solanine content of the cell culture samples and leaves and flowers of three cultivars belonging to three different Capsicum species, an HPLC-UV method was validated for this purpose as well. Despite validating a sensitive and specific method for capsiate analysis, no detectable amounts of capsiate were detected in any of the cell culture samples. Cell cultures of pungent cultivars did not produce detectable amounts of capsaicinoids either. Results from analyzing the real fruit samples were in accordance with previous literature reports, and Aji Dulce fruits were found to contain higher amounts of capsiate compared to Trinidad Pimento, although having only one indoor grown Aji Dulce fruit analyzed limits the reliability. The analytical method for determining α-solanine content had problems with internal standard and specificity. This method could be used for making rough estimates about the possible α-solanine content. No hazardous amounts were detected in any of the cell culture samples. Only one sample consisting of Aji Dulce young leaves could contain α-solanine slightly above the limits set for commercial potatoes. Results with flowers of Rocoto San Pedro Orange (C. pubescens) and Aji Omnicolor (C. baccatum) were inconclusive and it couldn’t be ruled out that they might contain large amounts of α-solanine. The reason why capsinoids, or even capsaicinoids, were not detected in the cell culture samples remains unsolved, but it could be speculated that capsinoids might degrade in the cell culture environment or that selection of cultivar or cell line is critical. This study gave further proof to the previous assumptions that chili leaves are safe and should not contain notable amounts of α-solanine.
  • Vidjeskog, Katarina (2021)
    Solunulkoiset vesikkelit eli EV:t ovat nanokokoisia solujen tuottamia lipidikaksoiskalvon peittämiä kalvorakkuloita. Solut vapauttavat EV:itä solunulkoiseen tilaan ja niitä on kaikissa kehon nesteissä. Aiemmin niiden uskottiin olevan vain solujen tapa päästä eroon tarpeettomasta materiaalista, mutta nykyisin tiedetään, että EV:illä on tärkeä merkitys solujenvälisessä viestinnässä. Sitä mukaa kun ymmärrys EV:iden merkityksestä on kasvanut, on kasvanut myös kiinnostus niiden tutkimiseen. EV:itä voidaan eristää lähes kaikista kehon nesteistä, mutta veressä niitä on erityisen runsaasti. Plasman EV:t ovat pääosin peräisin punasoluista ja verihiutaleista. Kun nanopartikkelit ovat kosketuksissa veren kaltaisten biologisten nesteiden kanssa, niiden ympärille muodostuu proteiinirakenne, jota kutsutaan proteiinikoronaksi. Proteiinikoronan koostumus vaikuttaa nanopartikkeleiden pintaominaisuuksiin. Se voi vaikuttaa myös esimerkiksi niiden soluinteraktioihin ja signalointiominaisuuksiin. Tämän pro gradutyön tarkoituksena oli tutkia punasolujen ja niistä tuotettujen nanoerytrosomien EV tyypin proteiinikoronan määrää ja vertailla näitä määriä toisiinsa. Mittaukset suoritettiin ihmisen veri plasmasta, joka oli pitoisuudeltaan 100 %:sta, 50 %:sta sekä 25 %:sta. Verestä peräisin olevien EV:iden etu sekä mahdollisina lääkekuljettimina, että tutkimuskäytössä on se, että ne ovat myrkyttömiä, heikosti immunogeenisiä, helposti saatavissa olevia, helppokäyttöisiä sekä varastoitavia. Tutkimustulosten perusteella proteiinikoronan määrä on EryEV:illä ja NanoEry:illä samaa suuruusluokkaa. Havaittavaa eroa ei ainakaan näin pienellä otoskoolla ollut havaittavissa.
  • Toppari, Antti (2011)
    Nowadays growing number of new active pharmaceutical ingredients (API) have large molecular weight and are hydrophobic. The energy of their crystal lattice is bigger and polarity has decreased. This leads to weakened solubility and dissolution rate of the drug. These properties can be enhanced for example by amorphization. Amorphous form has the best dissolution rate in the solid state. In the amorphous form drug molecules are randomly arranged, so the energy required to dissolve molecules is lower compared to the crystalline counterpart. The disadvantage of amorphous form is that it is unstable. Amorphous form tends to crystallize. Stability of amorphous form can be enhanced by adding an adjuvant to drug product. Adjuvant is usually a polymer. Polymers prevent crystallization both by forming bonds with API molecules and by steric hindrance. The key thing in stabilizing amorphous form is good miscibility between API and polymer. They have to be mixed in a molecular level so that the polymer is able to prevent crystallization. The aim of this work was to study miscibility of drug and polymer and stability of their dispersion with different analytical methods. Amorphous dispersions were made by rotary evaporator and freeze dryer. Amorphicity was confirmed with X-ray powder diffraction (XRPD) right after preparation. Itraconazole and theophylline were the chosen molecules to be stabilized. Itraconazole was expected to be easier and theophylline more difficult to stabilize. Itraconazole was stabilized with HPMC and theophylline was stabilized with PVP. Miscibility was studied with XRPD and differential scanning calorimetry (DSC). In addition it was studied with polarized light microscope if miscibility was possible to see visually. Dispersions were kept in stressed conditions and the crystallization was analyzed with XRPD. Stability was also examined with isothermal microcalorimetry (IMC). The dispersion of itraconazole and theophylline 40/60 (w/w) was completely miscible. It was proved by linear combination of XRPD results and single glass transition temperature in DSC. Homogenic well mixed film was observed with light microscope. Phase separation was observed with other compositions. Dispersions of theophylline and PVP mixed only partly. Stability of itraconazole dispersions were better than theophylline dispersions which were mixed poorer. So miscibility was important thing considering stability. The results from isothermal microcalorimetry were similar to results from conventional stability studies. Complementary analytical methods should be used when studying miscibility so that the results are more reliable. Light microscope is one method in addition to mostly used XRPD and DSC. Analyzing light microscope photos is quite subjective but it gives an idea of miscibility. Isothermal microcalorimetry can be one option for conventional stability studies. If right conditions can be made where the crystallization is not too fast, it may be possible to predict stability with isothermal microcalorimetry.
  • Rahikainen, Otto (2023)
    Ramansironta on sähkömagneettisen säteilyn ilmiö, jonka avulla voidaan havaita molekyylivärähdyksiä niistä sironneen valon avulla. Kun sähkömagneettinen säteily kohtaa molekyylin se voi häiritä elektronipilveä ytimen ympärillä ja prosessin lopputuloksena energiaa vapautuu sironneen säteilyn muodossa. Tätä kutsutaan epäelastiseksi sironnaksi. Mikäli sironnassa ei tapahdu fotonin energiassa muutosta kyseessä on elastinen siroaminen. Mikäli näytteeseen menevän ja sironneen fotonin välillä havaitaan energian muutos, käytetään ilmiöstä nimeä epäelastinen Raman sironta. Energian muutosta voidaan mitata, ja saatu spektri antaa tietoa kohdemolekyylistä. Tämän työn tarkoituksena oli tutkia eri Raman-spektroskopiatekniikoiden, lähinnä spontaani-Raman spektroskopian sekä koherentti anti-Stokes Ramanspektroskopian ja mikroskopian soveltuvuutta lääkemolekyylien havaitsemiseen sekä nanopartikkeleiden karakterisoinnissa ja nanopartikkeleiden ja solujen välisten interaktioiden tutkimisessa. Tekniikan vahvuuksiin kuuluu käytön suhteellinen helppous ja CARS-mikroskopian nopeus sekä korkea erotuskyky, mahdollisuus havainnoida solunäytteitä, ja epätodennäköisyys vaurioittaa tutkittavaa kohdetta. Haasteisiin lukeutuu fluoresenssin taipumus häiritä signaalia, spontaani-Raman mikroskopian heikompi erottelukyky, analyysin hitaus sekä tarve valikoida molekyyli, jonka rakenne antaisi vahvan Raman-signaalin. Tutkimuksen alatavoitteina oli sopivan lääkemolekyylin valitseminen nanopartikkeliformulaatioon, nanopartikkeleiden formulointi, niiden karakterisointi Raman-spektroskopiatekniikoilla, ja lopulta tutkia Raman spektroskopian soveltuvuutta nanopartikkeleiden ja lääkeaineen sekä solujen interaktioiden tutkimisessa ja lääkeaineen havaitsemisessa solujen sisältä. Tutkimuksessa uutta on se, että ensimmäistä kertaa polymeerinanopartikkeleiden ja niihin ladattujen lääkeaineiden soluunkulkeutumisen tutkiminen pelkällä Raman-spektroskopialla ilman esim. fluoresoivia merkkiaineita. Tutkimuksen tavoitteen pääasiallisesti täyttyivät. Valitsimme kohdemolekyyliksi klorotaloniilin, fungisidin joka on edullinen ja antaa selvästi tunnistettavan Raman-signaalin. Klorotaloniilille suoritettiin normaalit sytotoksisuuskokeet sekä vapaana lääkeaineena että formuloituina nanopartikkeleina. Nanopartikkelien formulointi onnistui ja molemmat Raman-spektroskopiatekniikat näyttivät selvästi sekä lääkemolekyylin että polymeerin kemikaalispesifiset Raman signaalit. Lääkemolekyylin havaitsemin solujen sisältä onnistui. Polymeerimolekyylit eivät missään vaiheessa kulkeutuneet solujen sisälle. Tämä oli ehkä yllättävää koska käytimme makrofageja, mutta toisaalta myös johdonmukainen muiden tutkimusten kanssa. Raman-tekniikat osoittautuivat hyviksi tutkimusmenetelmiksi, ja erityisesti CARS-mikroskoopin suuri erotuskyky osoittautui hyödylliseksi soluunkulkeutumisen kuvantamisessa.
  • Berg, Staffan (2013)
    The usage of polymer conjugation to modulate the biopharmaceutical behavior of both protein drugs as well as small molecule drugs is discussed. Emphasis has been given to polyethylene glycol (PEG) and poly[N-(2-hydroxypropyl)methacrylamide] (PHPMA) but also other polymers are looked into. Drug products on the market as well as drug candidates in clinical trials are used as examples when reviewing different polymers. The material is looked upon from a biopharmaceutical point of view. In the experimental part a polymer-drug conjugate for the treatment of ovarian cancer is synthesized and characterized. The conjugate has a HPMA polymer backbone with the anticancer drug gemcitabine attached through enzymatically labile Gly-Phe-Leu-Gly linkers. The conjugate is expected to target passively and actively to cancer tissue. The enhanced permeation and retention effect is responsible for the passive targeting, while Fab' fragments of OV-TL16 monoclonal antibodies provide the active targeting of the copolymer conjugate. In vitro cytotoxicity studies of a PHPMA-gemcitabine conjugate (without active targeting) was carried out on two ovarian cancer cell lines, A2780S and A2780AD. The IC50 values of the conjugate was shown to be 50.6 nM and 14.3 nM for A2780S and A2780AD, respectively. The corresponding IC50 values for free gemcitabine were 7.0 nM for the A2780S cell line and 3.9 nM for A2780AD cells. A preliminary in vivo efficacy study in mice with subcutaneous A2780AD tumor xenografts showed that a PHMA-gemcitabine conjugate given at a dose of 15 mg/kg (gemcitabine equivalence) was able to shrink the tumor volume by 50 % while only inducing minor body weight loss.