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  • Mäkitalo, Laura (Helsingin yliopisto, 2010)
    Matrix metalloproteinases (MMPs) represent a family of 23 metalloendopeptidases, collectively capable of degrading all components of the extracellular matrix. MMPs have been implicated in several inflammatory processes such as arthritis, atherosclerosis, and even carcinomas. They are also involved in several beneficial activities such as epithelial repair. MMPs are inhibited by endogenous tissue inhibitors of matrix metalloproteinases (TIMP). In this study, MMPs were investigated in intestinal mucosa of inflammatory bowel diseases (IBD), chronic intestinal disorders. The main focus was to characterize mucosal inflammation in the intestine, but also cutaneous pyoderma gangrenosum (PG), to assess similarites with IBD inflammation. MMPs and TIMPs were mainly examined in colonic mucosa, in adult Crohn s disease (CD), and paediatric CD, ulcerative colitis (UC), and indeterminate colitis (IC). Ileal pouch mucosa of proctocolectomized paediatric onset IBD patients was also investigated to characterize pouch mucosa. The focus was on finding specific MMPs that could act as markers to differentiate between different IBD disorders, and MMPs that could be implied as markers for tissue injury, potentially serving as targets for MMP-inhibitors. All examinations were performed using immunohistochemistry. The results show that immunosuppressive agents decrease stromal expression of MMP-9 and -26 that could serve as specific targets for MMP-inhibitors in treating CD. In paediatric colonic inflammation, MMP-10 and TIMP-3 present as molecular markers for IBD inflammation, and MMP-7 for CD. MMP expression in the the pouch mucosa could not be classified as strictly IBD- or non-IBD-like. For the first time, this study describes the expression of MMP-3, -7, -9, -12, and TIMP-2 and -3 in pouch mucosa. The MMP profile in PG bears resemblance to both intestinal IBD inflammation and cutaneous inflammation. Based on the results, MMPs and their inhibitors emerge as promising tools in the differential diagnosis of IBD and characterization of the disease subtype, although further research is necessary. Furthermore, the expression of several MMPs in pouch has been described for the first time. While further research is warranted, the findings contribute to a better understanding of events occurring in IBD mucosa, as well as pyoderma gangrenosum.
  • Mäkinen, Laura K. (Helsingin yliopisto, 2015)
    Predicting the clinical course of an early-stage oral tongue squamous cell carcinoma (OTSCC) is challenging, as even small tumors can behave aggressively. OTSCC often metastasizes to the cervical lymph nodes, and the presence of lymph node metastasis at the time of diagnosis is considered the most important tumor-related prognostic factor in OTSCC. The mechanisms of this disease progression are poorly understood. Despite slight improvement in the prognosis of OTSCC in recent decades, the outcome of these patients is still modest. Therefore, a deeper understanding of the phenomena behind tumor progression would enable medical professionals to evaluate the aggressiveness of the disease and to adjust its treatment more effectively. The extracellular matrix and basement membrane must be broken down before a tumor can invade surrounding tissues and further spread into blood and lymph vessels. This is a process that involves various proteolytic enzymes, the most important of which are matrix metalloproteinases (MMPs). Over 25 structurally related, but genetically distinct, human MMPs have been identified and characterized: collagenases, gelatinases, stromelysins, matrilysins, membrane-type MMPs, and other MMPs. Toll-like receptors (TLRs) are pattern-recognition molecules involved in innate immunity that are also expressed in many types of cancer. TLRs apparently play a pivotal role in malignant disease: they are related to tumor progression and, conversely, to cancer inhibition. Their expression pattern and role in oral cancer, however, remains unclear. In this thesis we studied the expression of MMPs 2, 7, 8, 9, 13, and 25 and TLRs 2, 4, 5, 7, and 9 in early-stage OTSCC. The study comprised 73 consecutive clinically T1N0M0 and T2N0M0 OTSCC patients treated at the Helsinki University Hospital, Helsinki, Finland in 1992-2002. We prepared tissue array blocks from primary tumors and immunostained them. We also used whole section slides from patients with metastasized or recurrent disease. We compared immunoexpression of MMPs and TLRs to tumor and patient characteristics as well as to patient outcomes. We also used Western immunoblot to examine TLR-2 and -4 expression in the highly invasive and aggressive HSC-3 OTSCC cell line. In addition, we studied the effect of TLR-2 and -4 antagonist GIT27 (4,5-dihydro-5-isoxasoleacetic acid) on the invasion of the HSC-3 cell line in myoma organotypic invasion assay. OTSCC tumors expressed both MMPs and TLRs. Nuclear expression of MMP-13, but not cytoplasmic expression of MMP-2, -8, and -9, associated with deeper invasion and advanced tumor size. Furthermore, high nuclear MMP-13 expression predicted poor disease-specific survival. High MMP-7 protein expression associated with the presence of occult cervical metastases, increased invasion depth, and higher tumor grade, and also predicted poor outcome. Immunostaining of MMP-25 failed to correlate with any clinical parameters. High TLR-2, -4, and -9 expression correlated with deeper tumor invasion. Cytoplasmic expression of TLR-2 and -4 also correlated significantly with higher tumor grade, whereas high TLR-5 expression associated with lower tumor grade. High expression of TLR-9 correlated with advanced tumor size. Negative or mild TLR-5 expression predicted poor disease-specific survival. OTSCC primary tumors, neck metastases and recurrent tumors expressed TLR-2, -4, and -9. TLR-2 and -4 antagonist GIT27 did not affect the invasion of the HSC-3 cell line in myoma organotypic invasion assay. Thus, TLRs may operate under a different mechanism of action depending on whether they are activated by damage-associated molecular patterns in cancer or by pathogen-associated molecular patterns in infection. Our results suggest that MMP-7 and MMP-13 in particular may have prognostic value in OTSCC. Their use as prognostic biomarkers, however, calls for further study. TLR-2, -4, and -9 seemed to predict invasive tumor growth. Primary tumors and neck metastases as well as recurrent tumors of OTSCC express these TLRs, suggesting that TLRs seem to play a role in both the development and progression of tongue carcinoma.
  • Kuivanen, Tiina (Helsingin yliopisto, 2008)
    The incidence of non-melanoma skin cancer is increasing worldwide. Basal cell carcinoma followed by squamous cell carcinoma and malignant melanoma are the most frequent skin tumors. Immunosuppressed patients have an increased risk of neoplasia, of which non-melanoma skin cancer is the most common. Matrix metalloproteinases (MMPs) are proteolytic enzymes that collectively are capable of degrading virtually all components of the extracellular matrix. MMPs can also process substrates distinct from extracellular matrix proteins and influence cell proliferation, differentiation, angiogenesis, and apoptosis. MMP activity is regulated by their natural inhibitors, tissue inhibitors of metallopro-teinases (TIMPs). In this study, the expression patterns of MMPs, TIMPs, and certain cancer-related molecules were investigated in premalignant and malignant lesions of the human skin. As methods were used immunohistochemisty, in situ hybridization, and reverse transcriptase polymerase chain reaction (RT-PCR) from the cell cultures. Our aim was to evaluate the expression pattern of MMPs in extramammary Paget's disease in order to find markers for more advanced tumors, as well as to shed light on the origin of this rare neoplasm. Novel MMPs -21, -26, and -28 were studied in melanoma cell culture, in primary cutaneous melanomas, and their sentinel nodes. The MMP expression profile in keratoacanthomas and well-differentiated squamous cell carcinomas was analyzed to find markers to differentiate benign keratinocyte hyperproliferation from malignantly transformed cells. Squamous cell carcinomas of immunosuppressed organ transplant recipients were compared to squamous cell carcinomas of matched immunocompetent controls to investigate the factors explaining their more aggressive nature. We found that MMP-7 and -19 proteins are abundant in extramammary Paget's disease and that their presence may predict an underlying adenocarcinoma in these patients. In melanomas, MMP-21 was upregulated in early phases of melanoma progression, but disappeared from the more aggressive tumors with lymph node metastases. The presence of MMP-13 in primary melanomas and lymph node metastases may relate to more aggressive disease. In keratoacanthomas, the expression of MMP-7 and -9 is rare and therefore should raise a suspicion of well-differentiated squamous cell carcinomas. Furthermore, MMP-19 and p16 were observed in benign keratinocyte hyperproliferation of keratoacanthomas, whereas they were generally lost from malignant keratinocytes of SCCs. MMP-26 staining was significantly stronger in squamous cell carcinomas and Bowen s disease samples of organ transplant recipients and it may contribute to the more aggressive nature of squamous cell carcinomas in immunosuppressed patients. In addition, the staining for MMP-9 was significantly stronger in macrophages surrounding the tumors of the immunocompetent group and in neutrophils of those patients on cyclosporin medication. In conclusion, based on our studies, MMP-7 and -19 might serve as biomarkers for more aggressive extramammary Paget's disease and MMP-21 for malignant transformation of melanocytes. MMP -7, -9, and -26, however, could play an important role in the pathobiology of keratinocyte derived malignancies.
  • Hästbacka, Johanna (Helsingin yliopisto, 2013)
    The systemic levels of matrix metalloproteinases (MMPs) -7, -8 and -9 and the tissue inhibitor of metalloproteinases-1 (TIMP-1) were investigated in 877 critically ill patients. In Study I, 15 intensive care unit-(ICU) treated adult patients with secondary peritonitis were prospectively included. Peritoneal fluid, blood and urine samples were collected at the ICU after surgery. The serum and urine levels of MMP-8 were compared with those obtained from ten healthy volunteers, and were found to be significantly higher in patients. In peritoneal fluid, MMP-8 levels were significantly higher than in serum and urine. This study was the first to identify MMP-8 in the peritoneal fluid of peritonitis patients. Study II was a sub-study of the FINNSEPSIS study where patients with severe sepsis or septic shock were prospectively included in 24 Finnish ICUs. Serum samples of 248 patients were analysed for MMP-8, MMP-9 and TIMP-1 levels, that were found to be higher than those of healthy controls. MMP-8, -9 and TIMP-1 levels were compared between ICU survivors and non-survivors. Median MMP-8 (p<0.01) and TIMP-1 (p<0.001) were higher and median MMP-9 levels lower (p=0.047) in ICU non-survivors than in ICU survivors. Study III investigated MMP-7, MMP-8, MMP-9, and TIMP-1 levels on 51 patients resuscitated from cardiac arrest (CA). The patients were a subgroup of the Hypothermia After Cardiac Arrest study. Thirty patients had received mild therapeutic hypothermia treatment (MTH) and 21 non-hypothermia treatment (non-MTH). Serum samples taken at 24 and 48 hours from restoration of spontaneous circulation were analysed and compared between patients and healthy volunteers. Serum MMP and TIMP-1 levels of MTH-treated patients were compared during and after MTH with the levels of non-MTH-treated patients. MMP-8 and MMP-9 were higher in CA patients than controls. Patients receiving MTH treatment had lower median MMP-9 levels during MTH than non-MTH-treated patients (p<0.001). This is one novel potential mechanism of how MTH treatment improves outcome of CA patients. Study IV was a 563-patient sub-study of the FINNALI study that included acute respiratory failure patients at 25 Finnish ICUs. MMP-8 and TIMP-1 were analysed from blood samples taken on study admission and 48 hours thereafter. Association of MMP-8 and TIMP-1 with 90-day mortality was examined. Serum MMP-8 predicted 90-day mortality of acute respiratory failure patients poorly. Admission TIMP-1 levels were higher in non-survivors than in survivors (p<0.001).TIMP-1 was an independent predictor of 90-day mortality, with a moderate discriminative power (AUC 0.633, 95% CI 0.580- 0.686). TIMP-1 was also associated with the severity of oxygenation disturbance. Thus, TIMP-1 is a potentially useful biomarker for predicting outcome in acute respiratory failure patients.
  • Cederqvist, Katariina (Helsingin yliopisto, 2006)
    During inflammation, excess production and release of matrix proteinases, including matrix metalloproteinases (MMPs) and serine proteinases, may result in dysregulated extracellular proteolysis leading to development of tissue damage. Pulmonary inflammation may play an important role in the pathogenesis of lung injury in the preterm infant. The aims of this study were to evaluate involvement of MMPs and serine proteinase trypsin in acute and chronic lung injury in preterm infants and to study the role of these enzymes in acute lung injury by means of an animal model of hyperoxic lung injury. Molecular forms and levels of MMP-2, -8, and -9, and their specific inhibitor, tissue inhibitor of metalloproteinases (TIMP)-2, as well as trypsin were studied in tracheal aspirate fluid (TAF) samples collected from preterm infants with respiratory distress. Expression and distribution of trypsin-2 and proteinase-activated receptor 2 (PAR2) was examined in autopsy lung specimens from fetuses, from preterm infants with respiratory distress syndrome (RDS) or bronchopulmonary dysplasia (BPD), and from newborn infants without lung injury. We detected higher MMP-8 and trypsin-2 and lower TIMP-2 in TAF from preterm infants with more severe acute respiratory distress. Infants subsequently developing BPD had higher levels of MMP-8 and trypsin-2 early postnatally than did those who survived without this chronic lung injury. Immunohistochemically, trypsin-2 was mainly detectable in bronchial epithelium, but also in alveolar epithelium, and its expression was strongest in prolonged RDS. Since trypsin-2 is potent activator of PAR2, a G-protein coupled receptor involved in inflammation, we studied PAR2 expression in the lung. PAR2 co-localized with trypsin-2 in bronchoalveolar epithelium and its expression was significantly higher in bronchoalveolar epithelium in preterm infants with prolonged RDS than in newborn controls. In the experimental study, rats were exposed to >95% oxygen for 24, 48, and 60 hours, or room air. At 48 hours of hyperoxia, MMP-8 and trypsin levels sharply increased in bronchoalveolar lavage fluid, and expression of trypsin appeared in alveolar epithelium, and MMP-8 predominantly in macrophages. In conclusion, high pulmonary MMP-8 and trypsin-2 early postnatally are associated with severity of acute lung injury and subsequent development of BPD in preterm infants. In the injured preterm lung, trypsin-2 co-localizes with PAR2 in bronchoalveolar epithelium, suggesting that PAR2 activated by high levels of trypsin-2 is involved in lung inflammation associated with development of BPD. Marked increase in MMP-8 and trypsin early in the course of experimental hyperoxic lung injury suggests that these enzymes play a role in the pathogenesis of acute lung injury. Further exploration of the roles of trypsin and MMP-8 in lung injury may offer new targets for therapeutic intervention.
  • Määttä, Vesa (2010)
    Matti Laurila (1895 1983) This is a biographical research of a Jaeger officer, a Civil Guard Chief, a Field Commander Matti Laurila. A broader practice of qualitative methods was utilized in the research. The main aim is a permanent reconstruction and reinterpretation of past events through the experiences of the study object. The life and times of Laurila are intertwined with the crucial events that led to the Finnish Declaration of Independence. Afterwards he helped to ensure that the young republic also stayed independent. As a Jaeger in the winter of 1917 Laurila witnessed an incident he would never forget. After disobeying a direct order, Sven Saarikoski from Lapua was shot dead by his commanding officer, K. A. Ståhlberg, on the ice of the river Aa. Laurila faced the horrors of war at closer quarters, for he lost his father and his brother in the battle of Länkipohja on 16th March 1918. This battle was a major turning point for Laurila and profoundly influenced the rest of his life. The relationship between Laurila and his superiors was problematic almost throughout his military career, haunted as he was by the memory of Sven Saarikoski's execution and the losses in Länkipohja The position of Laurila as an authority in South Ostrobothnia was a key factor in preventing the extreme right from rallying enough Civil Guard troops to escalate the embryonic Mäntsälä rebellion of 1932. After the rebellion Laurila routinely opposed anything he saw as a threat to the independence of the Civil Guard. He would flatly refuse to even consider the integration of the Civil Guard into the national defence force. His uncompromising stand in this matter annoyed some among the higher ranking officers. After the Winter War Laurila got himself into a dispute with Jaeger Colonel H. E. Hannuksela that would have long-lasting consequences. The conflicts between them became widely known in the attack phase of the Continuation War in 1941 at the latest. Laurila had to give up his military career at the end of 1944. In the years that followed he did what he could to ensure that the South Ostrobothnia Civil Guard patrimony remained in the province. Laurila's position as a respected authority in South Ostrobothnia remained unchanged until his death.
  • Kushnerenko, Elena V. (Helsingin yliopisto, 2003)
  • Berghäll, Liisa (Helsingin yliopisto, 2010)
    This dissertation provides a synchronic grammatical description of Mauwake, a Papuan (Trans-New Guinea) language of about 2000 speakers on the North Coast of the Madang Province in Papua New Guinea. The theoretical background is that of Basic Linguistic Theory (BLT), used extensively in analysing and writing descriptive grammars. The chapters from morphology to clause level are described from form to function; in the later chapters the function is taken more often as the starting point. Any theory-specific terminology is kept to the minimum and formalisms have been avoided in accordance with BLT principles. Mauwake has a classic 5-vowel system and 14 consonant phonemes. With its simple phonology it is a typical representative of the Madang North Coast languages. For a Papuan language there are relatively few morphophonological alternations. Nouns are either alienably or inalienably possessed. There is no obligatory number marking in nouns or noun phrases. Pronouns have several different forms: five for case and three for other functions. The dative pronouns are treated as [+human] locatives, and they have also grammaticalised as possessives. The verbal morphology is agglutinative and mainly suffixal. Unusual features include two distributive suffixes, and the interaction of the derivational benefactive and the inflectional beneficiary suffixes. The applicative suffix has either transitivising or causative but not benefactive function. The switch-reference system distinguishes between simultaneous and sequential action, as well as same or different subject in relation to the following clause. There are several verbs denoting coming and going, and they may combine with one of three prefixes to indicate bringing and taking. Mauwake is a nominative-accusative type language, and the basic constituent order in a clause is SOV. Subject and object are the only syntactic arguments. There is no indirect object, but a clause can have two or even three objects. A nominalised clause with a finite verb functions as a relative clause or a complement clause; one with a nominalised verb has several different functions. Functional domains described include modality, negation, deixis, quantification, possession and comparison. As there are four negators, Mauwake has more variation in negative expressions than is usual in Papuan languages. Clause chaining is the preferred strategy for joining clauses into sentences, but coordination and subordination of finite clauses are also common. The form of a complement clause depends on whether it is of the fact, action or potential type. Tail-head linkage is used as a cohesive device between sentences. The discourse-level features described are topic and focus.
  • Pearson, Meeri (Helsingin yliopisto, 2013)
    This dissertation investigated the impacts of soil preparation after clearcutting Scots pine (Pinus sylvestris L.) forest on thick-peated soil from silvicultural and climatic standpoints. Three growing seasons after outplanting, mounding most effectively secured seedling survival, growth, and vitality through improved soil aeration of the planting spot. However, other presumed benefits of mounding to seedlings such as warmer soil temperatures and faster organic matter decomposition were not confirmed here. Regeneration in scalps was unsuccessful due to waterlogged soil. Importantly when scalping, only the humus layer should be scraped off without creating depressions in the peat. Seedling tolerance to desiccated as well as waterlogged peat soil over one growing season was remarkable in controlled conditions. The impact of drought, however, was more immediate and severe as root and shoot growth, fractional colonization of ectomycorrhizal fungi, and root hydraulic conductance were reduced. Nevertheless, maintenance of rather high photochemical efficiency (expressed as variable to maximal chlorophyll fluorescence, Fv/Fm) especially in current-year needles despite harsh drought seemed to indicate a potential for seedling recovery. Polyamine analysis also revealed that new needles are preferred in protecting the different parts of the seedlings against drought stress. Wet-stressed seedlings, on the other hand, exhibited few signs of suffering. It was also demonstrated how the experimental environment a controlled versus field setting influences seedling tolerance to stress. The differing moisture levels within comparable microsites dry vs. wet scalps and ditch vs. inverted mounds had little influence on seedling growth and condition although physiological upset (i.e., Fv/Fm) was evident within scalps. Namely, the wetter the soil was, the lower Fv/Fm was. The fear of soil preparation accelerating GHG emissions, particularly CO2, from peat into the atmosphere appears unwarranted at least on nutrient-poor, boreal forestry-drained peatland sites. The overall climatic impact of soil preparation, in the forms of mounding and scalping, three years after application expressed in terms of CO2 equivalents (100-year GWP), was neutral compared to leaving soil unprepared. The core findings of this research support mounding as the best alternative on nutrient-poor, drained peatland sites when the goal is to maximize the regeneration success of Scots pine after clearcutting with minimal impact on soil GHG emissions. In the future, development of soil preparation methodology is particularly deserving of further attention. While it may not be the sexiest research topic in the worldwide rat race of the modern day, it is nonetheless of substantial importance in a country highly specialized not only in the utilization but also the rejuvenation of wood resources on drained peatlands. Keywords: forestry-drained peat soil, clearcutting, mounding, scalping, CO2, CH4, and N2O fluxes, drought and waterlogging stress