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Despite recent advances in immunotherapies for lung cancer, their success is still hindered by limited predictability of treatment outcomes in patients, as well as by resistance-conveying tumor mutations such as EGFR. Moreover, due to the vast number of treatment options and their cost, a quick, reliable, and cost-efficient drug screening platform is needed to select the optimal treatments for each individual patient. This thesis focuses on finding the best culture conditions to be used in such a future platform, employing 3D cell cultures and microfluidics to mimic in vivo tumors while saving costs and allowing for high-throughput screening. Image-based analysis showed that culture medium can have significant impacts on both cancer organoid growth and morphology, as well as drug sensitivity to the EGFR-inhibiting drug Osimertinib. Specific medium factors, such as the antioxidant N-acetylcysteine, might be particularly important for the integrity of 3D structures in the platform and help prevent conversion to an adherent morphology. Moreover, flow cytometry analysis of immune cells from pleural effusion samples indicated that medium composition might facilitate creating an inflammatory environment in the platform, and that immune cells should not be cultured longer than one week to maximize their activity. Finally, this thesis compares two microfluidic devices for their suitability to be used in future high-throughput drug-screening applications, by contrasting their ease of handling, applicability in fluorescent imaging-based readouts, and possibility to mimic and study the tumor microenvironment in vitro. The results suggest that the choice of microfluidic device will be dependent on whether microscopy analysis or cell viability assays will be used as the main readout of the drug screening in the future.

A robust energy metabolism in humans relies on functional insulin-producing beta cells for maintenance of normoglycemia. Dysfunctional beta cells or malfunctioning insulin is the underlying cause for all forms of diabetes. With current management of different types of diabetes, patients continue to face life-threatening risk of hypoglycemia and other associated pathologies. Research has been challenging due to difficulties in studying beta cells in vitro, as human donor-derived beta cells do not expand well in laboratory conditions. At the time when this study was performed, only a few protocols had been published for beta-cell differentiation. These protocols were often difficult to reproduce in different cell lines and resulted in a low yield of differentiated cells. Both pancreas and liver develop from the same precursor cells called the definitive endoderm (DE). Factors directing the differentiation of definitive endoderm towards a pancreatic endocrine progenitor fate are not fully known. Previous unpublished data indicated the presence of transforming growth factor beta (TGF-β) superfamily inhibitors in the early stages of a developing murine pancreas. In this study, protocols for producing pancreas-specific endoderm cells from human pluripotent stem cells (hPSC) were tested and developed further. The primary aim of this study was to inhibit TGF-β mediated signaling, follow-up and report the effects in definitive endoderm specification. Human embryonic stem cells (hESC) and human induced pluripotent stem cells (hiPSC) were differentiated into definitive endoderm (DE) using directed differentiation, followed by five experimental conditions with TGF-β inhibitors. Quantitative real-time PCR (q-PCR), flow-cytometry (FC), immunocytochemistry (ICC), and –fluorescence (IF) techniques were used to examine the gene- and protein expression of the cells at specific time points of the protocol. The gene expression levels of known hepatic and pancreatic markers were analyzed and compared between the cell lines. The current DE differentiation protocol, consisting of the DE stage, followed by a four-day culture, showed a downregulation of hepatic markers with and without TGF-β inhibitors. The examined protocols resulted in heterogenic cell populations, consequent to previously reported challenges in beta-cell progenitor differentiation. This study provided valuable information and a platform for further research on the differentiation of pancreatic endocrine progenitor cells.

OptiVein® on kehitetty helpottamaan kanylointeja. Laite kiinnitetään tavalliseen verisuonikanyyliin. Kanyylin sisällä sijaitsee kertakäyttöinen, steriili valokuitu, jota pitkin kulkeva lasersäde näkyy vihreänä valona kanyylin päässä. Valo on niin voimakas, että se kuultaa ihon läpi. Tämän tutkimuksen tarkoitus on selvittää, auttaako OptiVein kokemattomien kanyloijien onnistumista laskimon kanyloinnissa. Tutkielmassa pohditaan myös muita kanyloinnin apuvälineitä sekä niiden suhdetta OptiVeiniin.

Inflammatoriska tarmsjukdomar (IBD) är en paraplyterm för Crohns sjukdom (CD) och ulcerös kolit (UC). Sjukdomarna har en stark koppling till munhålan och dess infektioner. IBD patienter uppvisar flertalet orala symptom i munnen, så som mukobuckal hyperplasi, gingival svullnad, ulcerationer, aftor, candida, lichen planus, leukoplack, orofacial granulomatos, pyostomatitis vegetans och recidiverande aftös stomatit. Orala infektioner är ett utbrett folkhälsoproblem och även inflammatoriska tarmsjukdomar kan redan klassas som en folksjukdom tack vare sin stora incidens. Gemensamma etiologiska faktorer och interaktioner mellan olika orala infektioner och inflammatoriska tarmsjukdomar är en viktig del i pusslet för att förstå sjukdomarnas patofysiologi. I denna litteraturöversikt tas orala symptom, karies, gingivit, parodontit och oral candidos samt deras anknytningar till kroniska inflammatoriska tarmsjukdomar upp.

Background: Oral contraceptive (OC) use may increase the risk of specific cancers and mortality. The aims of this study were to investigate the association between OC use and its duration with the risk of breast cancer, to examine the overall mortality associated with OC use and its duration, and finally to identify sociodemographic characteristics of OC use. Methods: Data are derived from the Older Finnish Twin cohort consisted of monozygotic and same-sexed dizygotic twin pairs born before 1958. We included N = 9,607 Finnish twin women aged 18 – 49 years old with information on OC use and other covariates. The information on OC use, reproductive, and lifestyle factors was collected using a mailed questionnaire. The information on breast cancer incidence was obtained from the Finnish Cancer Registry and the data on mortality was collected from the national Population Information System and Statistics Finland. We used Cox proportional hazards regression to estimate the association between OC use and its duration with risk of breast cancer and overall mortality while controlling for potential confounders. Also, we used logistic regression to identify sociodemographic characteristics of OC use. All tests of statistical significance were two-sided. Results: A total of 758 women developed breast cancer during median follow-up of 42.6 years. Women who ever used OC had 20% greater risk of developing breast cancer than women who never used (HR =1.20, 95% CI = 1.02 to 1.40, P = 0.02). Women who used OC for more than 5 years had greater risk of developing the disease than those who used OC for less than 2 years (HR = 1.11, 95% CI = 0.85 to 1.46), however, the results did not reach the statistical significance. Mortality did not significantly different between women who had ever used OC with those who had not used OC while controlling for potential confounders. Current smokers and women who consumed alcohol more than 10 gram/day had the highest odds of ever using OC. Conclusion: Our results suggest that OC use slightly increases the risk of breast cancer, however, no evidence from this study indicates that OC use adversely affect long-term risk for mortality.

Bad breath or oral malodour can be related to gingival diseases, trimethylaminuria, various inflammation diseases of upper respiratory tract, foreign bodies in nasal cavity etc. Bad breath is usually, in 85 % to 95 % of cases, inflicted by gram negative anaerobic bacteria in tongue coating. These bacteria have a tendency of producing foul-smelling sulphur containing gases called volatile sulphur compounds or VSC. Main cause of bad breath is parodontitis or postnasal drip into posterior part of the tongue. Detecting bad breath is most efficiently done by organoleptic method. By skilled analyser the reason for oral malodour can be determined with great accuracy. For scientific study the most effective method is gas chromatography (GC) with flame photometric detector (FPD). With it almost every component of exhaled air can be detected both quantitative and qualitative. Effective chairside methods include portable sulphur monitors and saliva tests.

Orbitan eksenteraatio on harvinainen ja mutiloiva toimenpide, jossa silmäkuopan sisältö pehmytkudoksineen poistetaan. Aiheesta on vain rajallisesti tutkimustietoa toimenpiteen harvinaisuuden takia. Lisäksi siihen johtavien tautien, pääsääntöisesti pahanlaatuisten kasvainten, monimuotoisuus hankaloittaa tutkimusta. Leikkauksessa silmäkuopan kasvain pyritään yleensä poistamaan radikaalisti. Toimenpiteen vaikuttavuus eliniänennusteeseen on ajoittain kyseenalaistettu, sillä ei ole varmuutta, onko sairaus jo ehtinyt lähettämään mikroetäpesäkkeitä ennen leikkausta ja olisiko näissä tapauksissa ollut järkevämpää tehdä silmän säästävä leikkaus. Suomessa suurin osa eksenteraatioista tehdään HUS:ssa ja yksittäisiä leikkauksia muissa sairaanhoitopiireissä. Tämän retrospektiivisen tutkimuksen tarkoitus oli tarkastella HUS:ssa 2005–2022 tehtyjen orbitan eksenteraatioiden määrää ja kartoittaa missä, millä indikaatiolla ja minkä erikoisalan toimesta leikkaukset on tehty. Lisäksi tavoitteena oli kerätä tärkeimmät potilasta, tautia ja hoitoa koskevat muuttujat ja verrata tietoja muiden julkaisujen tuloksiin. HUS Tietohallinnon toimittamasta 1618:sta silmäkuoppatoimenpiteen aineistosta identifioitiin 67 orbitan eksenteraatiota, jotka kaikki sisällytettiin tutkimukseen. Tarvittavat tiedot kerättiin potilastietojärjestelmistä ja analysoitiin taulukkolaskentaohjelmalla. Leikkauksissa osallisina oli plastiikkakirurgeja, silmäkirurgeja, korva-, nenä- ja kurkkutautien erikoislääkäreitä, neurokirurgeja ja suu- ja leukakirurgeja vaihtelevissa määrin ja leikkauksia tehtiin kaikkien näiden alojen yksiköissä. Indikaatioita leikkaukselle olivat eri syöpätaudit ja yhdessä tapauksessa hyvänlaatuinen kasvain. Komplikaatioita esiintyi 40,3 % potilaista, mutta näistä suurin osa oli lieviä. Kaksi potilasta kuitenkin menehtyi leikkauksen jälkeisiin komplikaatioihin. Yleisin komplikaatio oli rekonstruktiossa käytetyn mikrovaskulaarisen kudossiirteen perfuusion ongelma. Osa potilaista säilyi leikkauksen jälkeen tautivapaina, osalla tauti uusiutui ja osa ei missään vaiheessa saavuttanut tautivapaata tilaa. Keskimääräinen aika taudin uusiutumiseen oli 22 kuukautta. Tutkimus on tiettävästi Pohjoismaissa ensimmäinen laatuaan ja maailmanlaajuisestikin suurempia tutkimuksia aiheesta on vain rajallisesti [1]. Tutkimuksessa kerättyä ja analysoitua tietoa voidaan jatkossa käyttää eksenteraatiotoimenpiteiden kehittämiseen ja perustana lisätutkimuksille.

Original antigenic sin (OAS) is an immunological phenomenon in which an initial antigen dominates the immune response toward subsequently encountered closely related antigens. As a result, the immune response against the primary antigen is boosted and a specific immune response toward the infecting antigen is attenuated in heterologous secondary infections. This may have various consequences, including aggravation of heterologous secondary infections, complication of vaccine development, and disturbance of serological diagnostics. This thesis is a literature review describing OAS in selected human viral infections and its clinical impact. A publication I worked on, demonstrating OAS in human bocavirus infections for the first time, is included. This thesis discusses what is known to date, limitations of past studies and gives recommendations for future research. Understanding OAS is necessary for the development of safe and effective vaccines and therapies, and accurate diagnostics for some of the most devastating infections of our time.

Respirometry is a polarographic method that provides insights into mitochondrial respiratory capacity – specifically to electron transport chain (ETC) complexes I to V –, mitochondrial integrity and energy metabolism. The limitation of the respiratory measurements has been that it requires freshly isolated mitochondria or tissue sample. Long-term preservation of mitochondrial function in frozen samples has been a considerable challenge, since the membrane integrity of the mitochondria is lost during the freezing process. Thus, samples do not display coupled respiration. However, previous studies have found that despite coupled respiration is impaired the individual ETC complexes and the ability of ETC supercomplexes to consume oxygen are not destroyed due to freezing and thawing. On the basis of this knowledge, recently published article presented a novel protocol that overcomes the damages caused by freeze-thaw cycles. The protocol also enables respiration measurement of ETC complexes I-IV by using Seahorse XF96 Extracellular flux analyzer. In this MSc thesis I modified and optimized the aforementioned protocol for Oroboros O2k high- resolution respirometry using frozen skeletal muscle samples. In addition, this study provides an optimized sample preparation protocol for frozen muscle samples and respiration measurement. The new method broadens the possibilities within mitochondrial respiration studies since Oroboros O2k high-resolution respirometry records results with high sensitivity without limiting the number of substrates used. The possibility to use frozen samples reduces research costs, simplifies logistics and enables retrospective studies with previously stored frozen tissue samples. I also utilized the optimized respiration measurement protocol to study metabolic effects of combined gene therapy in skeletal muscle. This gene therapy mimics the positive effects of exercise by inducing skeletal muscle growth and angiogenesis. The mimicking effect was induced by systemic delivery of adeno-associated viral vectors encoding pro-myostatin and VEGF-B. In previous studies inhibition of myostatin has been connected to compromised oxidative capacity and vascular rarefaction. In contrast, VEGF-B has demonstrated to induce angiogenesis in several tissues. Thus, my hypothesis was that combination gene therapy would result in better mitochondrial function than pro-myostatin alone. Results from this study indicate that moderate inhibition of myostatin signaling by pro-myostatin using rAAV vectors could provide enhancements in ETC function when it is induced independently or combined with rAAV-VEGF-B. This result lays a solid foundation for future research and could provide a new therapeutic option against muscle loss and related metabolic diseases.

Tutkimuksen tavoitteena oli selvittää ortodonttien tilannetta Suomessa: ikä- ja sukupuolijakaumaa, pää- ja sivutyöpaikkojen alueellista jakautumista kunta- ja sairaanhoitopiiritasolla, ortodonttien työssäkäyntialueita sekä sitä, oliko syntymä- ja koulutuspaikkakunnalla merkitystä myöhemmän työskentelypaikkakunnan valinnassa. Tutkimuksessa tarvittavat tiedot kerättiin aineiston pohjana olevaan listaan Suomen työikäisistä oikomishoidon erikoishammaslääkäreistä. Tutkimusaineistoa analysoitiin ja käsiteltiin tilastollisin keinoin. Tulokset havainnollistettiin teemakarttojen, diagrammien sekä taulukoiden avulla. Vuonna 2010 Suomessa toimi 159 ortodonttia, joista 75 prosenttia oli yli 45-vuotiaita. Eniten ortodontteja oli sijoittunut hammaslääketieteen koulutusta antavien yliopistokaupunkien, Helsingin, Turun ja Oulun, läheisyyteen. Vähiten ortodontteja työskenteli Itä- ja Pohjois-Suomen kunnissa. Jokaisessa sairaanhoitopiirissä ortodonttien määrä suhteessa väestöön oli liian pieni. 40 prosentilla ortodonteista sivutyöpaikka sijaitsi yli 50 kilometrin päässä päätyön paikkakunnasta ja 19 prosentilla yli 100 kilometrin päässä päätyön paikkakunnasta. Syntymä- ja ylioppilaaksitulon paikkakunnalla oli vaikutusta siihen, minne hakeuduttiin perustutkintoa opiskelemaan. Perustutkinnon suorittaneista keskimäärin 40 prosenttia jäi töihin samaan sairaanhoitopiiriin, jossa koulutusta antanut yliopisto sijaitsi. Yli puolet ortodonteista teki erikoistumisopinnot samassa yliopistossa kuin perusopinnot ja suurin osa jäi myös saman sairaanhoitopiirin alueelle töihin erikoistuttuaan.