Redox-linked proton transfer by cytochrome c oxidase

The respiratory chain is found in the inner mitochondrial membrane of higher organisms and in the plasma membrane of many bacteria. It consists of several membrane-spanning enzymes, which conserve the energy that is liberated from the degradation of food molecules as an electrochemical proton gradient across the membrane. The proton gradient can later be utilized by the cell for different energy requiring processes, e.g. ATP production, cellular motion or active transport of ions. The difference in proton concentration between the two sides of the membrane is a result of the translocation of protons by the enzymes of the respiratory chain, from the negatively charged (N-side) to the positively charged side (P-side) of the lipid bilayer, against the proton concentration gradient. The endergonic proton transfer is driven by the flow of electrons through the enzymes of the respiratory chain, from low redox-potential electron donors to acceptors of higher potential, and ultimately to oxygen. Cytochrome c oxidase is the last enzyme in the respiratory chain and catalyzes the reduction of dioxygen to water. The redox reaction is coupled to proton transport across the membrane by a yet unresolved mechanism. Cytochrome c oxidase has two proton-conducting pathways through which protons are taken up to the interior part of the enzyme from the N-side of the membrane. The K-pathway transfers merely substrate protons, which are consumed in the process of water formation at the catalytic site. The D-pathway transfers both substrate protons and protons that are pumped to the P-side of the membrane. This thesis focuses on the role of two conserved amino acids in proton translocation by cytochrome c oxidase, glutamate 278 and tryptophan 164. Glu278 is located at the end of the D-pathway and is thought to constitute the branching point for substrate and pumped protons. In this work, it was shown that although Glu278 has an important role in the proton transfer mechanism, its presence is not an obligatory requirement. Alternative structural solutions in the area around Glu278, much like the ones present in some distantly related heme-copper oxidases, could in the absence of Glu278 support the formation of a long hydrogen-bonded water chain through which proton transfer from the D-pathway to the catalytic site is possible. The other studied amino acid, Trp164, is hydrogen bonded to the ∆-propionate of heme a3 of the catalytic site. Mutation of this amino acid showed that it may be involved in regulation of proton access to a proton acceptor, a pump site, from which the proton later is expelled to the P-side of the membrane. The ion pair that is formed by the ∆-propionate of heme a3 and arginine 473 is likely to form a gate-like structure, which regulates proton mobility to the P-side of the membrane. The same gate may also be part of an exit path through which water molecules produced at the catalytically active site are removed towards the external side of the membrane. Time-resolved optical and electrometrical experiments with the Trp164 to phenylalanine mutant revealed a so far undetected step in the proton pumping mechanism. During the A to PR transition of the catalytic cycle, a proton is transferred from Glu278 to the pump site, located somewhere in the vicinity of the ∆-propionate of heme a3. A mechanism for proton pumping by cytochrome c oxidase is proposed on the basis of the presented results and the mechanism is discussed in relation to some relevant experimental data. A common proton pumping mechanism for all members of the heme-copper oxidase family is moreover considered.

GDP-L-fucose: synthesis and role in inflammation

GDP-L-fucose: synthesis and role in inflammation The migration of leukocytes from intravascular locations to extravascular sites is essential to the immune responses. The initial attachment of leukocytes to the endothelium and the rolling step of the leukocyte extravasation cascade are mediated by selectins, a family of cell adhesion molecules on cell surfaces. Selectins are able to recognize glycoproteins and glycolipids containing the tetrasaccharide sialyl Lewis x (sLex, Neu5Acα2-3Galβ1-4(Fucα1-3)GlcNAc). Several glycosyltransferases are involved in the biosynthesis of sLex, fucosyltransferase VII (Fuc-TVII) being the last enzyme to modify the sLex structure. Fuc-TVII transfers L-fucose from GDP-L-fucose to sialylated N-acetyllactosamine. GDP-L-fucose is synthesized in the cytosol via two different metabolic pathways. The major, constitutively active de novo pathway involves conversion of GDP-α-D-mannose to GDP-β-L-fucose. In the alternative salvage pathway, L-fucokinase synthesizes from free fucose L-fucose-1-phosphate, which is further converted to GDP-L-fucose by GDP-L-fucose pyrophosphorylase. GDP-L-fucose is translocated from the cytosol to Golgi for fucosylation via the GDP-fucose transporter. This thesis involved the study of the synthesis of GDP-L-fucose via the salvage pathway: cloning and expression of murine L-fucokinase and GDP-L-fucose pyrophosphorylase. The gene expression levels of these enzymes were found to be relatively high in various tissues; the mRNA levels were highest in brain, ovary and testis. This study also describes molecular cloning of rat fucosyltransferase VII (FUT7) and its expression as a functional enzyme. Gene expression levels of GDP-L-fucose synthesizing enzymes, GDP-fucose transporter and FUT7 were determined in inflamed tissues as well as cancer cells. Our results revealed a clear upregulation of the enzymes involved in the synthesis of GDP-L-fucose via de novo pathway, GDP-fucose transporter and FUT7 in inflamed tissues and in cancer cells. On the contrary, the GDP-L-fucose salvage pathway was found to be irrelevant in inflammation and in tumorigenesis. Furthermore, our results indicated the transcriptional coregulation of Golgi transporters involved in the synthesis of sulfo sLex, i.e. CMP-sialic acid, GDP-fucose and 3 phosphoadenosine 5 -phosphosulfate transporters, in inflammation.

Proton translocation coupled to electron transfer reactions in terminal oxidases

Terminal oxidases are the final proteins of the respiratory chain in eukaryotes and some bacteria. They catalyze most of the biological oxygen consumption on Earth done by aerobic organisms. During the catalytic reaction terminal oxidases reduce dioxygen to water and use the energy released in this process to maintain the electrochemical proton gradient by functioning as a redox-driven proton pump. This membrane gradient of protons is extremely important for cells as it is used for many cellular processes, such as transportation of substrates and ATP synthesis. Even though the structures of several terminal oxidases are known, they are not sufficient in themselves to explain the molecular mechanism of proton pumping. In this work we have applied a complex approach using a variety of different techniques to address the properties and the mechanism of proton translocation by the terminal oxidases. The combination of direct measurements of pH changes during catalytic turnover, time-resolved potentiometric electrometry and optical spectroscopy, made it possible to obtain valuable information about various aspects of oxidase functioning. We compared oxygen binding properties of terminal oxidases from the distinct heme-copper (CcO) and cytochrome bd families and found that cytochrome bd has a high affinity for oxygen, which is 3 orders of magnitude higher than that of CcO. Interestingly, the difference between CcO and cytochrome bd is not only in higher affinity of the latter to oxygen, but also in the way that each of these enzymes traps oxygen during catalysis. CcO traps oxygen kinetically - the molecule of bound dioxygen is rapidly reduced before it can dissociate. Alternatively, cytochrome bd employs an alternative mechanism of oxygen trapping - part of the redox energy is invested into tight oxygen binding, and the price paid for this is the lack of proton pumping. A single cycle of oxygen reduction to water is characterized by translocation of four protons across the membrane. Our results make it possible to assign the pumping steps to discrete transitions of the catalytic cycle and indicate that during in vivo turnover of the oxidase these four protons are transferred, one at a time, during the P→F, F→OH, Oh→Eh, and Eh→R transitions. At the same time, each individual proton translocation step in the catalytic cycle is not just a single reaction catalyzed by CcO, but rather a complicated sequence of interdependent electron and proton transfers. We assume that each single proton translocation cycle of CcO is assured by internal proton transfer from the conserved Glu-278 to an as yet unidentified pump site above the hemes. Delivery of a proton to the pump site serves as a driving reaction that forces the proton translocation cycle to continue.

Expression, Enzymatic Activities and Subcellular Localization of Hepatitis E Virus and Semliki Forest Virus Replicase Proteins

Viruses are submicroscopic, infectious agents that are obligate intracellular parasites. They adopt various types of strategies for their parasitic replication and proliferation in infected cells. The nucleic acid genome of a virus contains information that redirects molecular machinery of the cell to the replication and production of new virions. Viruses that replicate in the cytoplasm and are unable to use the nuclear transcription machinery of the host cell have developed their own transcription and capping systems. This thesis describes replication strategies of two distantly related viruses, hepatitis E virus (HEV) and Semliki Forest virus (SFV), which belong to the alphavirus-like superfamily of positive-strand RNA viruses. We have demonstrated that HEV and SFV share a unique cap formation pathway specific for alphavirus-like superfamily. The capping enzyme first acts as a methyltransferase, catalyzing the transfer of a methyl group from S-adenosylmethionine to GTP to yield m7GTP. It then transfers the methylated guanosine to the end of viral mRNA. Both reactions are virus-specific and differ from those described for the host cell. Therefore, these capping reactions offer attractive targets for the development of antiviral drugs. Additionally, it has been shown that replication of SFV and HEV takes place in association with cellular membranes. The origin of these membranes and the intracellular localization of the components of the replication complex were studied by modern microscopy techniques. It was demonstrated that SFV replicates in cytoplasmic membranes that are derived from endosomes and lysosomes. According to our studies, site for HEV replication seems to be the intermediate compartment which mediates the traffic between endoplasmic reticulum and the Golgi complex. As a result of this work, a unique mechanism of cap formation for hepatitis E virus replicase has been characterized. It represents a novel target for the development of specific inhibitors against viral replication.

Planar Edgeless Detectors for the TOTEM Experiment at the LHC

The TOTEM experiment at the LHC will measure the total proton-proton cross-section with a precision better than 1%, elastic proton scattering over a wide range in momentum transfer -t= p^2 theta^2 up to 10 GeV^2 and diffractive dissociation, including single, double and central diffraction topologies. The total cross-section will be measured with the luminosity independent method that requires the simultaneous measurements of the total inelastic rate and the elastic proton scattering down to four-momentum transfers of a few 10^-3 GeV^2, corresponding to leading protons scattered in angles of microradians from the interaction point. This will be achieved using silicon microstrip detectors, which offer attractive properties such as good spatial resolution (<20 um), fast response (O(10ns)) to particles and radiation hardness up to 10^14 "n"/cm^2. This work reports about the development of an innovative structure at the detector edge reducing the conventional dead width of 0.5-1 mm to 50-60 um, compatible with the requirements of the experiment.

Electromagnetic signatures of lightning near the HF frequency band

The dissertation deals with remote narrowband measurements of the electromagnetic radiation emitted by lightning flashes. A lightning flash consists of a number of sub-processes. The return stroke, which transfers electrical charge from the thundercloud to to the ground, is electromagnetically an impulsive wideband process; that is, it emits radiation at most frequencies in the electromagnetic spectrum, but its duration is only some tens of microseconds. Before and after the return stroke, multiple sub-processes redistribute electrical charges within the thundercloud. These sub-processes can last for tens to hundreds of milliseconds, many orders of magnitude longer than the return stroke. Each sub-process causes radiation with specific time-domain characteristics, having maxima at different frequencies. Thus, if the radiation is measured at a single narrow frequency band, it is difficult to identify the sub-processes, and some sub-processes can be missed altogether. However, narrowband detectors are simple to design and miniaturize. In particular, near the High Frequency band (High Frequency, 3 MHz to 30 MHz), ordinary shortwave radios can, in principle, be used as detectors. This dissertation utilizes a prototype detector which is essentially a handheld AM radio receiver. Measurements were made in Scandinavia, and several independent data sources were used to identify lightning sub-processes, as well as the distance to each individual flash. It is shown that multiple sub-processes radiate strongly near the HF band. The return stroke usually radiates intensely, but it cannot be reliably identified from the time-domain signal alone. This means that a narrowband measurement is best used to characterize the energy of the radiation integrated over the whole flash, without attempting to identify individual processes. The dissertation analyzes the conditions under which this integrated energy can be used to estimate the distance to the flash. It is shown that flash-by-flash variations are large, but the integrated energy is very sensitive to changes in the distance, dropping as approximately the inverse cube root of the distance. Flashes can, in principle, be detected at distances of more than 100 km, but since the ground conductivity can vary, ranging accuracy drops dramatically at distances larger than 20 km. These limitations mean that individual flashes cannot be ranged accurately using a single narrowband detector, and the useful range is limited to 30 kilometers at the most. Nevertheless, simple statistical corrections are developed, which enable an accurate estimate of the distance to the closest edge of an active storm cell, as well as the approach speed. The results of the dissertation could therefore have practical applications in real-time short-range lightning detection and warning systems.

Straw Performance Studies and Quality Assurance for the ATLAS Transition Radiation Tracker

The Transition Radiation Tracker (TRT) of the ATLAS experiment at the LHC is part of the Inner Detector. It is designed as a robust and powerful gaseous detector that provides tracking through individual drift-tubes (straws) as well as particle identification via transition radiation (TR) detection. The straw tubes are operated with Xe-CO2-O2 70/27/3, a gas that combines the advantages of efficient TR absorption, a short electron drift time and minimum ageing effects. The modules of the barrel part of the TRT were built in the United States while the end-cap wheels are assembled at two Russian institutes. Acceptance tests of barrel modules and end-cap wheels are performed at CERN before assembly and integration with the Semiconductor Tracker (SCT) and the Pixel Detector. This thesis first describes simulations the TRT straw tube. The argon-based acceptance gas mixture as well as two xenon-based operating gases are examined for its properties. Drift velocities and Townsend coefficients are computed with the help of the program Magboltz and used to study electron drift and multiplication in the straw using the software Garfield. The inclusion of Penning transfers in the avalanche process leads to remarkable agreements with experimental data. A high level of cleanliness in the TRT s acceptance test gas system is indispensable. To monitor gas purity, a small straw tube detector has been constructed and extensively used to study the ageing behaviour of the straw tube in Ar-CO2. A variety of ageing tests are presented and discussed. Acceptance tests for the TRT survey dimensions, wire tension, gas-tightness, high-voltage stability and gas gain uniformity along each individual straw. The thesis gives details on acceptance criteria and measurement methods in the case of the end-cap wheels. Special focus is put on wire tension and straw straightness. The effect of geometrically deformed straws on gas gain and energy resolution is examined in an experimental setup and compared to simulation studies. An overview of the most important results from the end-cap wheels tested up to this point is presented.

Eläytymisestä omiin tarinoihin : Televisiosarja katsojien keskustelussa

From sympathetic understanding to own stories. TV-series in the conversation of its viewers. The purpose of this study is to analyze viewers' conversations about TV-series as a practice in which viewers construct meaning to TV-series. In the tradition of British Cultural Studies this study understands that viewer has an active role in interpreting and constructing meaning to TV-series. In the tradition of feminist studies this study understands that gender is being constructed in social and cultural practices. In reception studies, the viewing of TV-series has usually been analyzed as a practice which is embedded at home and in a family. The studies are often based on interviews of viewers, and the analysis of the construction of meaning is based on interview material where the viewers most often talk about their viewing habits and the likes and dislikes of TV-shows and -characters. This study extends the reception and interpretation of TV-series from home to the moments of interaction between viewers. It is quite common to hear how people talk also outside of home about television and the programmes they have watched. In this study the construction of meaning is being studied in viewers' conversations. The method of analysis is conversation analysis which studies the ordered properties of everyday forms of social interaction. The data has been collected in a workplace where four women watched together (and without the presence of a researcher) two TV-series, American sitcom Golden Girls and Finnish family drama Ruusun aika (Time of a Rose), and afterwards had time and chance for discussion. There was neither a questionnaire nor an agenda for the women to discuss. The analysis of the conversation brings up three themes. In the orientation discussions the viewers aim to construct frames in which it makes sense to talk about the TV-series. The frames have mostly to do with the genre of the TV-series. The second theme is concerned with the viewers' aim to achieve sympathetic understanding of the characters in the TV-series. The third theme extends and transfers the conversation about TV-series to real or imaginary stories of own life. In the conversation the reception of a TV-series appears as being in motion: in the orientation discussions the viewers move towards the series, in the character-discussions the viewers move within the world of the series, and when telling their own stories the viewers move away from the TV-series towards their own lives. In the conversations there appears also a distinction in gender-constructions. When the viewers talk about motherhood, they adopt a serious and moralistic tone. When they talk about female sexuality and relationships between women and men they adopt carnevalistic and humorous tone. There are examples of these kinds of gender-constructions also in other studies of Finnish gender culture. Motherhood means the responsibility to good upbringing; relationships with men include something unpredictable and problematic which one handles at best in a humorous way.

Neighborhood Shopkeepers in Contemporary South Korea: Household, Work, and Locality

This is an ethnographic study of the lived worlds of the keepers of small shops in a residential neighborhood in Seoul, South Korea. It outlines, discusses, and analyses the categories and conceptualizations of South Korean capitalism at the level of households, neighborhoods, and Korean society. These cultural categories were investigated through the neighborhood shopkeepers practices of work and reciprocal interaction as well as through the shopkeepers articulations of their lived experience. In South Korea, the keepers of small businesses have continued to be a large occupational category despite of societal and economic changes, occupying approximately one fourth of the population in active work force. In spite of that, these people, their livelihoods and their cultural and social worlds have rarely been in the focus of social science inquiry. The ethnographic field research for this study was conducted during a 14-month period between November 1998 and December 1999 and in three subsequent short visits to Korea and to the research neighborhood. The fieldwork was conducted during the aftermath of the Asian currency crisis, colloquially termed at the time as the IMF crisis, which highlighted the social and cultural circumstances of small businesskeeper in a specific way. The livelihoods of small-scale entrepreneurs became even more precarious than before; self-employment became an involuntary choice for many middle-class salaried employees who were laid off; and the cultural categories and concepts of society and economy South Korean capitalism were articulated more sharply than before. This study begins with an overview of the contemporary setting, the Korean society under the socially and economically painful outcomes of the economic crisis, and continues with an overview of relevant literature. After introducing the research area and the informants, I discuss the Korean notion of neighborhood, which incorporates both the notions of culturally valued Koreanness and deficiency in the sense of modernity and development. This study further analyses the ways in which the businesskeepers appropriate and reproduce the Korean ideas of men s and women s gender roles and spheres of work. As the appropriation of children s labor is conditional to intergenerational family trajectories which aim not to reproduce parents occupational status but to gain entry to salaried occupations via educational credentials, the work of a married couple is the most common organization of work in small businesses, to which the Korean ideas of family and kin continuity are not applied. While the lack of generational businesskeeping succession suggests that the proprietors mainly subscribe to the notions of familial status that emanate from the practices of the white-collar middle class, the cases of certain women shopkeepers show that their proprietorship and the ensuing economic standing in the family prompts and invites inversed interpretations and uses of common cultural notions of gender. After discussing and analyzing the concept of money and the cultural categorization of leisure and work, topics that emerged as very significant in the lived world of the shopkeepers, this study charts and analyses the categories of identification which the shopkeepers employ for their cultural and social locations and identities. Particular attention is paid to the idea of ordinary people (seomin), which shopkeepers are commonly considered to be most representative of, and which also sums up the ambivalence of neighborhood shopkeepers as a social category: they are not committed to familial reproduction and continuity of the business but aspire non-entrepreneurial careers for their children, while they occupy a significant position in the elaborations of culturally valued notions and ideologies defining Koreanness such as warmheartedness and sociability.

Growing up in Affiliation with a Religious Community : A Case Study of Seventh-day Adventist Youth in Finland

This study investigates how the religious community as a socialization context affects the development of young people's religious identity and values, using Finnish Seventh-day Adventism as a context for the case study. The research problem is investigated through the following questions: (1) What aspects support the intergenerational transmission of values and tradition in religious home education? (2) What is the role of social capital and the social networks of the religious community in the religious socialization process? (3) How does the religious composition of the peer group at school (e.g., a denominational school in comparison to a mainstream school) affect these young people s social relations and choices and their religious identity (as challenged versus as reinforced by values at school)? And (4) How do the young people studied negotiate their religious values and religious membership in the diverse social contexts of the society at large? The mixed method study includes both quantitative and qualitative data sets (3 surveys: n=106 young adults, n=100 teenagers, n=55 parents; 2 sets of interviews: n=10 young adults and n=10 teenagers; and fieldwork data from youth summer camps). The results indicate that, in religious home education, the relationship between parents and children, the parental example of a personally meaningful way of life, and encouraging critical thinking in order for young people to make personalized value choices were important factors in socialization. Overall, positive experiences of the religion and the religious community were crucial in providing direction for later choices of values and affiliations. Education that was experienced as either too severe or too permissive was not regarded as a positive influence for accepting similar values and lifestyle choices to those of the parents. Furthermore, the religious community had an important influence on these young people s religious socialization in terms of the commitment to denominational values and lifestyle and in providing them with religious identity and rooting them in the social network of the denomination. The network of the religious community generated important social resources, or social capital, for both the youth and their families, involving both tangible and intangible benefits, and bridging and bonding effects. However, the study also illustrates the sometimes difficult negotiations the youth face in navigating between differentiation and belonging when there is a tension between the values of a minority group and the larger society, and one wants to and does belong to both. It also demonstrates the variety within both the majority and the minority communities in society, as well as the many different ways one can find a personally meaningful way of being an Adventist. In the light of the previous literature about socialization-in-context in an increasingly pluralistic society, the findings were examined at four levels: individual, family, community and societal. These were seen as both a nested structure and as constructing a funnel in which each broader level directs the influences that reach the narrower ones. The societal setting directs the position and operation of religious communities, families and individuals, and the influences that reach the developing children and young people are in many ways directed by societal, communal and family characteristics. These levels are by nature constantly changing, as well as being constructed of different parts, like the pieces of a jigsaw puzzle, each of which alters in significance: for some negotiations on values and memberships the parental influence may be greater, whereas for others the peer group influences are. Although agency does remain somewhat connected to others, the growing youth are gradually able to take more responsibility for their own choices and their agency plays a crucial role in the process of choosing values and group memberships. Keywords: youth, community, Adventism, socialization, values, identity negotiations

Knowledge Transfer within Western Multinationals' Subsidiary Units in China and Finland - The Impact of Headquarter Control Mechanisms, Subsidiary Location and Social Capital (summary section only)

It is suggested that the ability and practices of how the multinational corporation (MNC) manages knowledge transfer among its geographically dispersed subsidiary units are crucial for the building and development of firm competitive advantage. However, cross-border transfer of valuable organizational knowledge is likely to be problematic and laborious, especially within diversified and differentiated MNCs. Using data collected from 164 western multinational companies’ subsidiary units located in China and Finland, this study aims to investigate cross-border knowledge transfer within the MNC. It explores a number of factors that influence the transfer of knowledge among units in the differentiated MNC. The study consists of five individual papers. Paper 1 investigates a range of organizational mechanisms that may positively influence a subsidiary’s propensity to undertake knowledge transfers to other parts of the corporation. Paper 2 explores the impact of subsidiary location on the motivational dispositions of knowledge receiving units to value and accept knowledge from subsidiaries located in economically less advanced countries. Paper 3 examines the influence of social capital variables on knowledge transfer in dyadic relationships between foreign-owned subsidiaries and their sister and patent units. Paper 4 provides some initial insights into potentially different effects of trust and shared vision in intra-organizational vs. inter-organizational relationships. Using a case study setting, Paper 5 explores means and mechanisms used in transferring human resource management practices to Western MNCs’ business units in China from a cultural perspective. The results of the study show that MNC management through choices regarding organizational controls can encourage and enhance corporate-internal knowledge transfer. It also finds evidence that more knowledge is transferred from subsidiaries located in an industrialized country (e.g., Finland) than subsidiaries located in a developing country (e.g., China). While the study has highlighted the importance of social capital in promoting knowledge transfer, it has also uncovered some new findings that the effect of trust and shared vision may be contingent upon different contexts. Finally, in Paper 5, a number of mechanisms used in transferring selected HRM practices and competences to the Chinese business units have been identified. The findings suggest that cultural differences should be taken into consideration in the choice and use of different transfer mechanisms.

The link between foreign aid, public investment and economic growth

Länsimaat ovat rahoittaneet kehitysyhteistyöhankkeita jo lähes kuuden vuosikymmenen ajan, mutta kehitysavun tehokkuudesta ei olla edelleenkään päästy yksimielisyyteen. Yksi avunantajamaiden tapa vaikuttaa kehitysavun tehokkuuteen, eli avun vaikutukseen vastaanottajamaan taloudellisen kasvun kiihdyttäjänä, on sitoa ne julkisen sektorin infrastruktuurihankkeisiin. Joissain tapauksissa tämä vaikuttaa avun vastaanottajan käytökseen ja asenteisiin kehitysapua kohtaan. Tutkielmassa käsitellään kehitysavun tehokkuutta tilanteessa, jossa se on sidottu julkisen sektorin investointeihin kehitysmaassa. Tutkimus pohjaa Kalaitzidakisin ja Kalyvitisin (2008) malliin, jossa osa kehitysmaan julkisen talouden investoinneista rahoitetaan kehitysavulla. Seuraavaksi tarkastellaan ylijäämää tavoittelevan käyttäytymisen (rent- seeking) vaikutusta kehitysavun tehokkuuteen pohjaten Economidesin, Kalyvitisin ja Philippopoulosin (2008) malliin. Tutkielmassa referoidaan lisäksi tutkimuskysymystä sivuavia empiirisiä tutkimuksia, esitellään aluksi tavallisimmat kehitysyhteistyön muodot, sekä esitellään talousteoreettisia näkökulmia kehitysyhteistyön tehokkuuden määrittelylle. Tutkielma perustuu puhtaasti teoreettisiin malleihin ja niissä sovelletut menetelmät ovat matemaattisia. Tutkielmassa käsitellään ensin tapaus, jossa kehitysyhteistyöllä rahoitetaan julkisen sektorin investointihankkeita. Jossain tapauksissa kehitysavun kasvu lasku siirtää vastaanottajamaan kulutusta julkisista investoinneista kulutukseen, jolloin kehitysyhteistyövaroin osittain rahoitettujen hankkeiden koko pienenee, ja suhteellinen tehokkuus laskee. Seuraavaksi tarkastellaan tilannetta, jossa kehitysyhteistyövaroista vain osa päätyy hankkeen rahoittamiseen, ja todetaan, että kehitysavun tehokkuus ja vaikutus maan kansantulon kasvuun vähenee talouden toimijoiden ylijäämää tavoittelevan käyttäytymisen (mukaan lukien korruptio) myötä entisestään. Tämän tutkimuksen perusteella voidaan todeta, että kehitysapu vaikuttaa kehittyvän maan talouden kasvuun tapauksessa, jossa julkisia infrastruktuurihankkeita rahoitetaan osittain maan omin verovaroin ja osittain kehitysyhteistyövaroin. Ylijäämää tavoitteleva käyttäytyminen vaikuttaa kehitysavun tehokkuuteen negatiivistesti vähentäen kehitysavun positiivisia kasvuvaikutuksia.

Interrelations between Dry Eye Syndrome and Tear Fluid Phospholipid Transfer Protein

The simplified model of human tear fluid (TF) is a three-layered structure composed of a homogenous gel-like layer of hydrated mucins, an aqueous phase, and a lipid-rich outermost layer found in the tear-air interface. It is assumed that amphiphilic phospholipids are found adjacent to the aqueous-mucin layer and externally to this a layer composed of non-polar lipids face the tear-air interface. The lipid layer prevents evaporation of the TF and protects the eye, but excess accumulation of lipids may lead to drying of the corneal epithelium. Thus the lipid layer must be controlled and maintained by some molecular mechanisms. In the circulation, phospholipid transfer protein (PLTP) and cholesteryl ester transfer protein (CETP) mediate lipid transfers. The aim of this thesis was to investigate the presence and molecular mechanisms of lipid transfer proteins in human TF. The purpose was also to study the role of these proteins in the development of dry eye syndrome (DES). The presence of TF PLTP and CETP was studied by western blotting and mass spectrometry. The concentration of these proteins was determined by ELISA. The activities of the enzymes were determined by specific lipid transfer assays. To study the molecular mechanisms involved in PLTP mediated lipid transfer Langmuir monolayers and asymmetrical flow field-flow fractionation (AsFlFFF) was used. Ocular tissue samples were stained with monoclonal antibodies against PLTP to study the secretion route of PLTP. Heparin-Sepharose affinity chromatography was used for PLTP pull-down experiments and co-eluted proteins were identified with MALDI-TOF mass spectrometry or Western blot analysis. To study whether PLTP plays any functional role in TF PLTP-deficient mice were examined. The activity of PLTP was also studied in dry eye patients. PLTP is a component of normal human TF, whereas CETP is not. TF PLTP concentration was about 2-fold higher than that in human plasma. Inactivation of PLTP by heat treatment or immunoinhibition abolished the phospholipid transfer activity in tear fluid. PLTP was found to be secreted from lacrimal glands. PLTP seems to be surface active and is capable of accepting lipid molecules without the presence of lipid-protein complexes. The active movement of radioactively labeled lipids and high activity form of PLTP to acceptor particles suggested a shuttle model of PLTP-mediated lipid transfer. In this model, PLTP physically transports lipids between the donor and acceptor. Protein-protein interaction assays revealed ocular mucins as PLTP interaction partners in TF. In mice with a full deficiency of functional PLTP enhanced corneal epithelial damage, increased corneal permeability to carboxyfluorescein, and decreased corneal epithelial occludin expression was demonstrated. Increased tear fluid PLTP activity was observed among human DES patients. These results together suggest a scavenger property of TF PLTP: if the corneal epithelium is contaminated by hydrophobic material, PLTP could remove them and transport them to the superficial layer of the TF or, alternatively, transport them through the naso-lacrimal duct. Thus, PLTP might play an integral role in tear lipid trafficking and in the protection of the corneal epithelium. The increased PLTP activity in human DES patients suggests an ocular surface protective role for this lipid transfer protein.

Magnetic resonance imaging and ultrasonography in brachial plexus birth injury

Brachial plexus birth injury (BPBI) is caused by stretching, tearing or avulsion of the C5-C8 or Th1 nerve roots during delivery. Foetal-maternal disproportion is the main reason for BPBI. The goal of this study was to find out the incidence of posterior subluxation of the humeral head during first year of life in BPBI and optimal timing of the ultrasonographic screening of the glenohumeral joint. The glenohumeral congruity and posterior subluxation of the humeral head associated to muscle atrophy were assessed and surgical treatment of the shoulder girdle as well as muscle changes in elbow flexion contracture were evaluated. The prospective, population based part of the study included all neonates born in Helsinki area during years 2003-2006. Patients with BPBI sent to the Hospital for Children and Adolescents because of decreased external rotation, internal rotation contracture or deformation of the glenohumeral joint as well as patients with elbow flexion contracture were also included in this prospective study. The incidence of BPBI was calculated to be 3.1/1000 newborns in Helsinki area. About 80% of the patients with BPBI recover totally during the follow-up within the first year of life. Permanent plexus injury at the age of one year was noted in 20% of the patients (0.64/1000 newborns). Muscle imbalance resulted in sonographically detected posterior subluxation in one third of the patients with permanent BPBI. If muscle imbalance and posterior subluxation are left untreated bony deformities will develop. All patients with internal rotation contracture of the glenohumeral joint presented muscle atrophy of the rotator cuff muscles. Especially subscapular and infraspinous muscles were affected. A correlation was found particularly between greatest thickness of subscapular muscle and subluxation of the humeral head, degree of glenoid retroversion, as well as amount of internal rotation contracture. Supinator muscle atrophy was evident among all the studied patients with elbow flexion contracture. Brachial muscle pathology seemed to be an important factor for elbow flexion contracture in BPBI. Residual dysfunction of the upper extremity may require operative treatment such as tendon lengthening, tendon transfers, relocation of the humeral head or osteotomy of the humerus. Relocation of the humeral head improved the glenohumeral congruency among patients under 5 years of age. Functional improvement without remodeling of the glenohumeral joint was achieved by other reconstructive procedures. In conclusion: Shoulder screening by US should be done to all patients with permanent BPBI at the age of 3 and 6 months. Especially atrophy of the subscapular muscle correlates with glenohumeral deformity and posterior subluxation of the humeral head, which has not been reported in previous studies. Permanent muscle changes are the main reason for diminished range of motion of the elbow and forearm. Relocation of the humeral head, when needed, should be performed under the age of 5 years.

Migration-Development Nexus in the Malawian Health Sector: European Union Blue Card – circular migration for development?

The European Union has agreed on implementing the Policy Coherence for Development (PCD) principle in all policy sectors that are likely to have a direct impact on developing countries. This is in order to take account of and support the EU development cooperation objectives and the achievement of the internationally agreed Millennium Development Goals. The common EU migration policy and the newly introduced EU Blue Card directive present an example of the implementation of the principle in practice: the directive is not only designed to respond to the occurring EU labour demand by attracting highly skilled third-country professionals, but is also intended to contribute to the development objectives of the migrant-sending developing countries, primarily through the tool of circular migration and the consequent skills transfers. My objective in this study is to assess such twofold role of the EU Blue Card and to explore the idea that migration could be harnessed for the benefit of development in conformity with the notion that the two form a positive nexus. Seeing that the EU Blue Card fails to differentiate the most vulnerable countries and sectors from those that are in a better position to take advantage of the global migration flows, the developmental consequences of the directive must be accounted for even in the most severe settings. Accordingly, my intention is to question whether circular migration, as claimed, could address the problem of brain drain in the Malawian health sector, which has witnessed an excessive outflow of its professionals to the UK during the past decade. In order to assess the applicability, likelihood and relevance of circular migration and consequent skills transfers for development in the Malawian context, a field study of a total of 23 interviews with local health professionals was carried out in autumn 2010. The selected approach not only allows me to introduce a developing country perspective to the on-going discussion at the EU level, but also enables me to assess the development dimension of the EU Blue Card and the intended PCD principle through a local lens. Thus these interviews and local viewpoints are at the very heart of this study. Based on my findings from the field, the propensity of the EU Blue Card to result in circular migration and to address the persisting South-North migratory flows as well as the relevance of skills transfers can be called to question. This is as due to the bias in its twofold role the directive overlooks the importance of the sending country circumstances, which are known to determine any developmental outcomes of migration, and assumes that circular migration alone could bring about immediate benefits. Without initial emphasis on local conditions, however, positive outcomes for vulnerable countries such as Malawi are ever more distant. Indeed it seems as if the EU internal interests in migration policy forbid the fulfilment of the PCD principle and diminish the attempt to harness migration for development to bare rhetoric.