Allegorisches Oratorium "Sieg der Zeit und der Wahrheit", Fassung 1757 : 2. Akt

Konserttitaltiointi Händelfestspiele Göttingen -festivaaleilta 1976.

Lethal weapons : novel approaches for receptor-targeted cancer cell elimination

The currently used forms of cancer therapy are associated with drug resistance and toxicity to healthy tissues. Thus, more efficient methods are needed for cancer-specific induction of growth arrest and programmed cell death, also known as apoptosis. Therapeutic forms of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) are investigated in clinical trials due to the capability of TRAIL to trigger apoptosis specifically in cancer cells by activation of cell surface death receptors. Many tumors, however, have acquired resistance to TRAIL-induced apoptosis and sensitizing drugs for combinatorial treatments are, therefore, in high demand. This study demonstrates that lignans, natural polyphenols enriched in seeds and cereal, have a remarkable sensitizing effect on TRAIL-induced cell death at non-toxic lignan concentrations. In TRAIL-resistant and androgen-dependent prostate cancer cells we observe that lignans repress receptor tyrosine kinase (RTK) activity and downregulate cell survival signaling via the Akt pathway, which leads to increased TRAIL sensitivity. A structure-activity relationship analysis reveals that the γ-butyrolactone ring of the dibenzylbutyrolactone lignans is essential for the rapidly reversible TRAIL-sensitizing activity of these compounds. Furthermore, the lignan nortrachelogenin (NTG) is identified as the most efficient of the 27 tested lignans and norlignans in sensitization of androgen-deprived prostate cancer cells to TRAIL-induced apoptosis. While this combinatorial anticancer approach may leave normal cells unharmed, several efficient cancer drugs are too toxic, insoluble or unstable to be used in systemic therapy. To enable use of such drugs and to protect normal cells from cytotoxic effects, cancer-targeted drug delivery vehicles of nanometer scale have recently been generated. The newly developed nanoparticle system that we tested in vitro for cancer cell targeting combines the efficient drug-loading capacity of mesoporous silica to the versatile particle surface functionalization of hyperbranched poly(ethylene imine), PEI. The mesoporous hybrid silica nanoparticles (MSNs) were functionalized with folic acid to promote targeted internalization by folate receptor overexpressing cancer cells. The presented results demonstrate that the developed carrier system can be employed in vitro for cancer selective delivery of adsorbed or covalently conjugated molecules and furthermore, for selective induction of apoptotic cell death in folate receptor expressing cancer cells. The tested carrier system displays potential for simultaneous delivery of several anticancer agents specifically to cancer cells also in vivo.

Superoxide dismutase 3-mediated cell survival and proliferation

This dissertation studies the signaling events mediated by the extracellular superoxide dismutase (SOD3). SOD3 is an antioxidant enzyme which converts the harmful superoxide into hydrogen peroxide. Overproduction of these reactive oxygen species (ROS) in the cellular environment as a result of tissue injury or impaired antioxidant defense system has detrimental effects on tissue integrity and function. However, especially hydrogen peroxide is also an important signaling agent. Ischemic injury in muscle causes acute oxidative stress and inflammation. We investigated the ability of SOD3 to attenuate ischemia induced inflammation and to promote recovery of skeletal muscle tissue. We found that SOD3 can downregulate the expression of several inflammatory cytokines and cell adhesion molecules thus preventing the accumulation of oxidant-producing inflammatory cells. Secondly, SOD3 was able to promote long-term activation of the mitogenic Erk pathway, but increased only briefly the activity of pro-survival Akt pathway at an early stage of ischemic inflammation, thus reducing apoptosis. SOD3 is a prominent antioxidant in the thyroid gland where oxidative stress is constantly present. We investigated the role of SOD3 in normal thyroid follicular cells and the changes in its expression in various hyperproliferative disorders. We first showed that SOD3 is TSH-responsive which indicated its participation in thyroid function. Its principal function seems to be in follicular cell proliferation since knockdown cells were deficient in proliferation. Additionally, it was overexpressed in goiter tissue. However, SOD3 was consistently downregulated in thyroid cancer cell lines and tissues. In conclusion, SOD3 is involved in tissue maintenance, cell proliferation and inflammatory cell migration. Its mechanisms of action are the activation of known proliferation/survival pathways, inhibition of apoptosis and regulation of adhesion molecule expression.

Venäjän federaatio ja kamppailu kansainvälisen terrorismin merkityksistä : uhkakuvan ja valtioidentiteetin rakentuminen ulko- ja turvallisuuspoliittisessa diskurssissa

Tässä Pro gradu –tutkielmassa tarkastellaan Venäjän osallistumista kansainvälisen terrorismin uhkakuvan ja terrorismin vastaisen taistelun ja sitä kautta oman identiteettinsä määrittelyyn. Valittu tutkimuskohde on tarkemmin Venäjän federaation ulko- ja turvallisuuspoliittinen diskurssi osana laajempaa kansainvälistä diskurssia vuosina 2001–2007. Terrorismin merkityksestä viime vuosina käyty kamppailu ja uhkakuvien määrittelyssä esiintyvä valta tekevät tutkimuskohteen valinnasta perustellun ja ajankohtaisen. Tutkimus perustuu konstruktivistiseen viitekehykseen, jonka pohjalta on laadittuaikaisempaan tutkimukseen nojautuen ulko- ja turval lisuuspolitiikan diskurssianalyyttinen teoria. Tämä teoria ohjaa työn tarkastelemaan uhkakuvien rakentumista valtioidenidentiteettien määrittelyyn liittyen ja suuntaa met odia analysoimaan merkitysrakenteita, jotka esiintyvät uhkakuvien representaatioiden takana. Asettamalla Venäjän diskurssi kansainvälisestä terrorismista järjestelmätasolla käydyn diskurssin kontekstiin kyetään tarkastelemaan niitä yhteisiä ymmärryksiä, mahdollisuuksia ja rajoituksia sekä ennen kaikkea kamppailua, joiden piirissä Venäjä osallistuu terrorismin uhkakuvan ja oman valtioidentiteettinsä rakentamiseen. Teoria ohjaa asettamaan tutkielman tarkemmiksi tutk imuskysymyksiksi, mitä ovat järjestelmätason diskurssin merkitysrakenteet ja ni iden vaikutus, miten Venäjä on ottanut osaa terrorismin määrittelyyn, mitä merkitysrakenteita on löydettävissä Venäjän diskurssista, mitä identiteettejä ja intressejä Venäjälle rakentuu näiden merkitysrakenteiden kautta ja mitä järjestelmätasolla käyty diskurssi kertoo kamppailusta terrorismin ja sen vastaisen taistelun merkityksestä. Järjestelmätason diskurssia sekä Venäjän osallistum ista siihen tarkastellaan yhdeksää eri terrorismiin liittyvää tapausta käsittelevien eri t oimijoiden selontekojen kautta. Tapaukset on valittu niiden merkittävyyden tai potentiaalisen merkittävyyden takia ja toimijat niiden ja terrorismin vastaisen sodan suhteen perusteella. USA nousee tutkielmassa tärkeimmäksi järjestelmätason toimijaksi tarkasteltaessa Venäjän diskurssille rakentuvia rajoja ja mahdollisuuksia. Venäjä osallistui 9.11.2001 tapahtumien jälkeen akt iivisesti kansainvälisen terrorismin uhkakuvan rakentamiseen aina vuosiin 2005 – 2007 saakka, jolloin sen ja Lännen suhteet heikkenivät osittain terrorismin vastaisen sodan käytäntöön liittyvistä syistä. Tämän jälkeen muut uhkakuvat ovat hallinneet Venäjän ulko- ja turvallisuuspoliittista diskurssia. Yksimielisestä alusta huolimatta Venäjän näkemys kansainvälisestä terrorismista kohtasi pian vastustusta Lännen taholta. Suurimmat näkemyserot perustuivat Irakin ja Tshetshenian sotaan. Kansainvälisen terrorismin uhkakuva ei kyen nyt ristiriitojen johdosta luomaan jaettua turvallisuuskäsitystä Venäjän ja Lännen välille, eikä näin ollen muodostamaan jaettuja identiteettejä tai intressejä. Tämä ilmiö tiivistyi Venäjän käyttämään kaksoisstandardien käsitteeseen. Venäjä siirtyi kamppailun tuloksena määrittelemään terrorismia Keski-Aasian ja Kaukasian piirissä. Kehitys vahvisti Venäjän suurvaltaidentiteettiä, joka oli ollut rakentamisen kohteena jo vuonna 2000. Analyysin tuloksena voidaan todeta, että kansainvälisen terrorismin diskurssin taustalla vaikutti useita merkitysrakenteita, joista jokainen määritteli terrorismin eri tavoin. Ajan kuluessa järjestelmätasolla voimakkaimpina olivat ns. sotadiskurssi sekä ihmisoikeusdiskurssi. Näitä vastustamaan rakentuivat Venäjän ulko- ja turvallisuuspolitiikassa realistinen ja sivilisaatiodiskurssit. Diskurssien tarkastelun perusteella voidaan väittää kansainvälisen terrorismin ja sen v astaisen taistelun olleen voimakkaan kamppailun kohteena tarkasteltavana ajanjaksona. Kaksi tärkeää tekijää kamppailun takana on ollut Lännen (USA ja tapauksittain vaihteleva Eu rooppa) ja Venäjän pyrkimys määritellä toisiaan ja terrorismin vastaiseen sotaan liittyvän oikeutuksen määrittelyn hallinta. Tutkielman pohjalta ei voida esittää yhtenäistä määritelmää venäläisestä kansainvälisen terrorismin uhkakuvasta johtuen sen monista erilaisista tasoista ja muodoista. Terrorismi määrittyi Venäjälle kuitenkin voimakkaasti Tshetshenian sodan kautta, mistä johtuu sen korostunut poliittisuus. Tshetshenian sodan ja kansainvälisen terrorismin yhteiseen uhkakuvaan kuului voimakkaasti näkemys ulkopuolisen valloituksen pelosta. Tämä pelko siirtyi tarkastellun ajanjakson lopulla koskemaan myös ”unilateraalien suurvaltojen” toimintaa. Kansainvälisen terrorismin uhkakuva rakentui siis tukemaan vanhempia näkemyksiä maailmanjärjestelmän toiminnasta sekä Venäjän valtioidentiteetistä.

Götterdämmerung

Lavataltiointi Osterfestspiele Salzburg -festivaaleilta 1970, ensi-ilta.

Lohengrin

Lavataltiointi Osterfestspiele Salzburg -festivaaleilta 1976.

Brühler Schlosskonzerte : "Psiche" von Johann Joseph Fux

Lavataltiointi Brühler Schlosskonzerte -festivaaleilta 1978.

Intracranial Nimodipine Implant: Feasibility and Implications for the Treatment of Subarachnoid Hemorrhage – A Pre-Clinical Study

Intracranial aneurysmal subarachnoid hemorrhage (aSAH) is a life-threatening condition requiring immediate neurocritical care. A ruptured aneurysm must be isolated from arterial circulation to prevent rebleeding. Open surgical clipping of the neck of the aneurysm or intra-arterial filling of the aneurysm sack with platinum coils are major treatment strategies in an acute phase. About 40% of the patients suffering from aSAH die within a year of the bleeding despite the intensive treatment. After aSAH, the patient may develop a serious complication called vasospasm. Major risk for the vasospasm takes place at days 5–14 after the primary bleeding. In vasospasm, cerebral arteries contract uncontrollably causing brain ischemia that may lead to death. Nimodipine (NDP) is used to treat of vasospasm and it is administrated intravenously or orally every four hours for 21 days. NDP treatment has been scientifically proven to improve patients’ clinical outcome. The therapeutic effect of L-type calcium channel blocker NDP is due to the ability to dilate cerebral arteries. In addition to vasodilatation, recent research has shown the pleiotropic effect of NDP such as inhibition of neuronal apoptosis and inhibition of microthrombi formation. Indeed, NDP inhibits cortical spreading ischemia. Knowledge of the pathophysiology of the vasospasm has evolved in recent years to a complex entity of early brain injury, secondary injuries and cortical spreading ischemia, instead of being pure intracranial vessel spasm. High NDP levels are beneficial since they protect neurons and inhibit the cortical spreading ischemia. One of the drawbacks of the intravenous or oral administration of NPD is systemic hypotension, which is harmful particularly when the brain is injured. Maximizing the beneficial effects and avoiding systemic hypotension of NDP, we developed a sustained release biodegradable NDP implant that was surgically positioned in the basal cistern of animal models (dog and pig). Higher concentrations were achieved locally and lower concentrations systemically. Using this treatment approach in humans, it may be possible to reduce incidence of harmful hypotension and potentiate beneficial effects of NDP on neurons. Intracellular calcium regulation has a pivotal role in brain plasticity. NDP blocks L-type calcium channels in neurons, substantially decreasing intracellular calcium levels. Thus, we were interested in how NDP affects brain plasticity and tested the hypothesis in a mouse model. We found that NDP activates Brain-derived neurotrophic factor (BDNF) receptor TrkB and its downstream signaling in a reminiscent of antidepressant drugs. In contrast to antidepressant drugs, NDP activates Akt, a major survival-promoting factor. Our group’s previous findings demonstrate that long-term antidepressant treatment reactivates developmental-type of plasticity mechanisms in the adult brain, which allows the remodeling of neuronal networks if combined with appropriate rehabilitation. It seems that NDP has antidepressant-like properties and it is able to induce neuronal plasticity. In general, drug induced neuronal plasticity has a huge potential in neurorehabilitation and more studies are warranted.

To divide or differentiate? : nestin-mediated regulation of Cdk5 in cell fate decisions

The molecular functions of the non-cell cycle-related Cyclin-dependent kinase 5 (Cdk5) have been of primary interest within the neuroscience field, but novel undertakings are constantly emerging for the kinase in tissue homeostasis, as well as in diseases such as diabetes and cancer. Although Cdk5 activation is predominantly regulated by specific non-cyclin activator protein binding, additional mechanisms have proved to orchestrate Cdk5 signaling in cells. For example, the interaction between the intermediate filament protein nestin and Cdk5 has been proposed to determine cellular fate during neuronal apoptosis through nestin-dependent adjustment of the sensitive balance and turnover of Cdk5 activators. While nestin constitutes a crucial regulatory scaffold for appropriate Cdk5 activation in apoptosis, Cdk5 itself phosphorylates nestin with the consequence of filament reorganization in both neuronal progenitors and differentiating muscle cells. Interestingly, the two proteins are often found coexpressed in various tissues and cell types, proposing that nestin-mediated scaffolding of Cdk5 and its activators may be applicable to other tissue systems as well. In the literature, the molecular functions of nestin have remained in the shade, as it is mostly exploited as a marker protein for progenitor cells. In light of these studies, the aim of this thesis was to assess the importance of the nestin scaffold in regulation of Cdk5 actions in cell fate decisions. This thesis can be subdivided into two major projects: one that studied the nature of the Cdk5-nestin interplay in muscle, and one that assessed their role in prostate cancer. During differentiation of a myoblast cell line, the filament formation properties of nestin was found to be crucial in directing Cdk5 activity, with direct consequences on the process of differentiation. Also the genetic knockout of nestin was found to influence Cdk5 activity, although differentiation per se was not affected. Instead, the genetic ablation of nestin had broad consequences on muscle homeostasis and regeneration. While the nestin-mediated regulation of Cdk5 in muscle was found to act in multiple ways, the connection remained more elusive in cancer models. Cdk5 was, however, established as a significant determinant of prostate cancer proliferation; a behavior uncharacteristic for this differentiation-associated kinase. Through complex and simultaneous regulation of two major prostate cancer pathways, Cdk5 was placed upstream of both Akt kinase and the androgen receptor. Its action on proliferation was nonetheless mainly exerted through the Akt signaling pathway in various cancer models. In summary, this thesis contributed to the knowledge of Cdk5 regulation and functions in two atypical settings; proliferation (in a cancer framework) and muscle differentiation, which is a poorly understood model system in the Cdk5 field. This balance between proliferation and differentiation implemented by Cdk5 is ultimately regulated (where present) by the dynamics of the cytoskeletal nestin scaffold.

From epithelial to mesenchymal: regulation of invasive cancer cell motility

Metastasis is the main cause of death among cancer patients. In order to initiate the metastatic cascade cancer cells have to undergo epithelial-to-mesenchymal transition (EMT). In EMT epithelial cells lose their cell-cell and cell-extracellular matrix (ECM) contacts and become more motile. The expression of the transcription factor Slug and of the mesenchymal intermediate filament vimentin is induced during EMT. Vimentin is often overexpressed in malignant epithelial cancers but the functional role of vimentin remains incompletely understood. In addition, kinases such as AKT and ERK are known to be involved in the regulation of EMT and cancer cell motility but the mechanisms underlining their functions are often unclear. Integrins are heterodimeric receptors that attach cells to the surrounding tissue and participate in regulating cell migration and invasion. Changes in integrin activity are linked to increased cell motility and further cancer metastasis. The aim for my PhD studies was to investigate the role of cellular signalling pathways and vimentin in the regulation of cancer cell motility and EMT. Our results revealed that in prostate cancer the downregulation of AKT1 and AKT2, but not AKT3, induces activation of cell surface 1-integrins leading to enhanced cell adhesion, migration and invasion. In addition, our findings demonstrated a reciprocal regulatory interaction between vimentin and ERK2 facilitating ERK-mediated phosphorylation of Slug at serine-87 (S87) in breast cancer. Surprisingly, Slug S87 phosphorylation is dispensable for E-cadherin repression but essential for the induction of vimentin and Axl expression in early onset of EMT. Our findings reveal previously unknown mechanistic information of how prostate and breast cancer cell motility and disease progression is regulated