Peroxisomal and mitochondrial enzymes involved in lipid metabolism : studies on function and regulation

Fatty acids constitute a major part of the energy that we obtain from the diet and are also the principal source for mammals to store energy. To use the incoming or stored fatty acids as energy, the fatty acids needs to be metabolized of which the majority of fatty acids will be degraded by the mitochondrial β-oxidation system that in the end generates energy to the cell in the form of ATP. However, this organelle is not able to handle all kinds of fatty acids of which very long chain fatty acids, long chain methylbranched fatty acids and dicarboxylic acids are such cumbersome fatty acids. Therefore a second organelle, the peroxisome, is required for metabolism of these particular fatty acids. Also peroxisomes contain a β-oxidation system and similar to the mitochondrial system is the initial substrate a CoA-esterified fatty acid, so-called acyl-CoA. This thesis will focus on some enzymes that are active on these acyl-CoA esters, but that are not directly involved in the β-oxidation per se. Instead they contribute to the regulation of both acyl-CoA and free coenzyme A levels in different cellular compartments. This thesis will also include how these fatty acid degrading systems can be regulated at gene level by affecting different transcription factors by dietary ligands and by fasting. The peroxisomal Nudix hydrolase 7α (NUD7α), previously believed to be a CoASH degrading enzyme, was demonstrated to be a medium chain diphosphatase, most active on medium chain acyl-CoA esters, to produce 3’,5’-ADP and the corresponding 4’- acylphosphopantetheine thereof. NUDT7α expression and activity was down regulated by PPARα activation, which would prevent CoASH degradation and support a high rate of the β-oxidation in peroxisomes during these conditions. Peroxisomes are not only needed for the degradation of complex lipids, but are also essential for many other metabolic pathways such as bile acid and etherphospholipid synthesis and the degradation of D-amino acids and glyoxylate. The expression of gene transcripts that code for the proteins involved in these peroxisomal pathways was investigated almost throughout the whole mouse body with the aim to map the tissue expression of these pathways. The peroxisomal β-oxidation system is present in all examined tissues, however with differences in magnitude. More specifically expressed pathways are e.g. glyoxylate and D-amino acid degradation pathways. Auxiliary enzymes to the peroxisomal β-oxidation showed tissue specific expression, suggesting a high degree of tissue specific metabolite patterns, also being dependent on the metabolic state. The study also shows that PPARα is of major importance for the regulation in liver of the peroxisomal “transcriptome” during fasting. Mitochondria degrade both fatty acids and amino acids and the mitochondrial acyl- CoA thioesterase 9 (ACOT9) was shown to hydrolyze both long chain acyl-CoAs as well as short chain acyl-CoA intermediates and products of branched-chain amino acid metabolism. Kinetic characterization of the enzyme suggests a thigh regulation of the activity during different metabolic conditions in the mitochondria. Dietary ω-3 PUFAs from fish oil (FO) and krill oil (KO) cause different changes in lipid profiles and gene regulation when supplemented to mice. FO lowered most plasma lipids whereas KO only significantly lowered non-esterified fatty acids in plasma. FO showed a classical PPARα activation response by up regulating genes for fatty acid utilization and oxidation whereas KO down regulates genes for cholesterol and fatty acid synthesis

The Collective Wisdom of Female Entrepreneurs: Success Factors That Contribute to Positive Financial Growth for Entrepreneurial Companies

Female entrepreneurs are creating businesses faster than the national average, but their average revenues are a quarter of male-owned business revenues. This thesis examines the critical factors that contribute to successful financial growth for female entrepreneurs. After reviewing the existing literature, six female entrepreneurs were interviewed about their financial growth experience. Using a narrative methodology, the author analyzed the stories in light of the literature and defined key success factors for financial growth. Four important characteristics emerged – vision, self-awareness, profitability mindset and confidence – that female entrepreneurs need to succeed during times of rapid growth. The entrepreneurs also relied on an internal finance expert, bootstrapping as a funding mechanism, and a strong management team to pursue financial growth

The Collective Wisdom of Female Entrepreneurs: Success Factors That Contribute to Positive Financial Growth for Entrepreneurial Companies

Female entrepreneurs are creating businesses faster than the national average, but their average revenues are a quarter of male-owned business revenues. This thesis examines the critical factors that contribute to successful financial growth for female entrepreneurs. After reviewing the existing literature, six female entrepreneurs were interviewed about their financial growth experience. Using a narrative methodology, the author analyzed the stories in light of the literature and defined key success factors for financial growth. Four important characteristics emerged – vision, self-awareness, profitability mindset and confidence – that female entrepreneurs need to succeed during times of rapid growth. The entrepreneurs also relied on an internal finance expert, bootstrapping as a funding mechanism, and a strong management team to pursue financial growth

The Collective Wisdom of Female Entrepreneurs: Success Factors That Contribute to Positive Financial Growth for Entrepreneurial Companies

Female entrepreneurs are creating businesses faster than the national average, but their average revenues are a quarter of male-owned business revenues. This thesis examines the critical factors that contribute to successful financial growth for female entrepreneurs. After reviewing the existing literature, six female entrepreneurs were interviewed about their financial growth experience. Using a narrative methodology, the author analyzed the stories in light of the literature and defined key success factors for financial growth. Four important characteristics emerged – vision, self-awareness, profitability mindset and confidence – that female entrepreneurs need to succeed during times of rapid growth. The entrepreneurs also relied on an internal finance expert, bootstrapping as a funding mechanism, and a strong management team to pursue financial growth

Uskonnollisuus ilman Uskontoa : John Deweyn uskonnollinen naturalismi

Tässä tutkielmassa tarkastelen John Deweyn A Common Faith -teoksessa esittämää näkemystä naturalistisesta uskonnosta. Tutkimus keskittyy siihen voidaanko Deweyn uskonnollista naturalismia pitää a) naturalistisena ja b) uskonnollisena. Näihin kysymyksiin vastatakseni käyn tutkielmassani läpi A Common Faithia edeltänyttä uskonnonfilosofista keskustelua Yhdysvalloissa sekä modernia filosofista tutkimuskirjallisuutta. A Common Faith on vuonna 1934 julkaistu kolmeen luentoon pohjautuva teos, jonka sivuilla Dewey pyrkii esittämään korvaavan uskonnollisen vaihtoehdon niille, jotka pitävät vanhoja institutionaalisia uskontoja älyllisesti epätyydyttävinä. Deweyn itse asettaa esityksessään uskon kohteeksi ihanteen ja aktuaalisen välisen dynaamisen suhteen. Kokemuksen uskonnollisen laatupiirteen irrottaminen jäykistä metafyysistä rakenteista ja kiinnittäminen ihanteisiin mahdollistaa Deweyn mukaan uudenlaisen paremman yhteiselämän ja mahdollistaa paremmalla tavalla yhteisöjen kehityksen. Tutkielmani analyysiosiossa totean, että huolimatta tietyistä tulkinnallisista epäselvyyksistä voidaan Deweyn esittämää näkemystä pitää naturalistisena. Samoin nojaten vahvasti Jerome Stonen relatiivisen transsendenssin käsitteeseen totean, että esitys täyttää tietyt uskonnollisuuden konseptuaaliset reunaehdot. Deweyn esityksen uskonnollisuus kulminoituu erityisesti tietynlaiseen kosmiseen optimismiin, kongregationalistiseen kääntymys-käsitykseen sekä naturalistiseen käsitykseen ykseydestä. Analyysiosiossa suhtaudun kuitenkin myös kriittisesti Deweyn uskonnolliseen naturalismiin liittyvään melioristiseen kehitysuskoon sekä Deweyn yhteisöllisen uskon kyvyttömyyteen ottaa yhteisöllisiä ongelmia vakavasti

Osseointegrated Titanium Implants for Limb Prostheses Attachments: Infectious Complications

Femoral amputation is a devastating event. Percutaneous, bone anchored prosthetic systems reduce problems associated with socket suspended prostheses, but the design is inherently vulnerable to infection. The aims of this thesis were to determine the risk of implant-associated infection, bacterial biofilm properties and the functional impact using this implant treatment regime. Definition of implant related osteomyelitis was based on clinical signs, radiography and positive tissue cultures. In 3-year prospective study 39 patients were evaluated twice for infectious frequency, clinical presentation, and its relation to bacterial flora at the skin-implant interface (Paper 1). The frequency of implant infection was 5% at inclusion and 18% at follow-up. The most common bacteria in superficial, and deep cultures were Staphylococcus aureus and coagulase-negative staphylococci. Despite frequent colonization by potentially virulent bacteria, limited disability, and only one implant removal was found. Phenotypical and genotypical biofilm formation was determined in 13 (7 staphylococcal, 6 enterococcal) osteomyelitis strains (Paper II). Antimicrobial resistance was tested with a novel combination of the Calgary biofilm MBEC device, and a custom-made susceptibility MIC plate. The majority of the strains produced biofilm with increased antimicrobial resistance, compared to their planktonic counterparts. Slime producing strains tolerated higher antimicrobial concentrations compared to non-producers. All staphylococcal strains carried ica genes. The long-term risk of implant-associated infection, and its relation to patient and method specific factors was determined in a 20-year retrospective analysis of the first 96 femoral implant patients (102 implants) (Paper III). A 10-year cumulative risk of 20% for developing osteomyelitis (16 patients), and a 10-year cumulative risk of 9 % for implant extraction due to osteomyelitis (10 patients) was found. Antibiotic treatment (median 3.5 months) and selective minor debridement, with retained implants, cured 7 out of 18 patients at the 24- month follow-up (Paper IV). Six patients were cured after implant extraction, and 5 had chronic low-grade infections with stable implants, but variable use of the external prosthetic leg. The most common pathogens were S. aureus and E. faecalis. C-reactive protein serum levels were significantly higher in patients with osteomyelitis caused by S. aureus than other pathogens. It is concluded that the finding of an increased risk of osteomyelitis with time using this implant system calls for; i) careful patient selection and information of long term risks, ii) further studies on infection control, iii) consideration of biofilm in treatment, and iv) improved diagnostics, and antibiotic delivery

The mammalian peroxisome - "its function and distribution"

Peroxisomes are essential organelles for normal cell functions in all organisms from yeast to human. Their important contribution in different metabolic pathways is clearly visible by the severe phenotypes seen in the majority of peroxisomal diseases, where the symptoms often leads to an early death. Peroxisomes are involved in the synthesis of etherphospholipids and bile acids, in the metabolism of certain amino acids, purines and glyoxylate, and do also harbour an advanced system for degradation of various types of fatty acids and complex lipids. Peroxisomes are dynamic organelles that respond to different physiological and pharmacological changes by changing their number and contents of certain proteins. We carried out a tissue expression and regulation study on the majority of all known peroxisomal proteins (here called the ‘Pexiome’) in mouse at mRNA level to investigate if and how the different pathways may differ in their expression through out the mouse body. We studied how the mRNA expression varies in liver, kidney and intestinal epithelial in response to 12 hrs fasting, and also the effect of peroxisome proliferator activating receptor α (PPARα) agonist administration on gene expression in liver. The results show that indeed the mRNA expression of different genes varies markedly among tissues, while a number of genes seem to have a very wide tissue expression, which is in line with the content of peroxisomes in all cell types. Interestingly, fasting has a profound effect on the expression of the ‘Pexiome’ and also affects the peroxisomal gene expression in a strongly tissue specific manner. By examination of mouse livers from fasted and PPARα agonist treated animals on PPARα (+/+) and PPARα (-/-) backgrounds, it was evident that the regulation of most of the peroxisomal genes by fasting is far more complex than just involving PPARα activation. We also carried out an in depth study on the mouse peroxisomal Nudix hydrolase 7α (NUDT7α), which had previously been shown to act as a CoASH diphosphatase. Our data show that NUDT7α preferably cleaves off 3’,5’-ADP from the CoA-moiety of medium chain acyl-CoA’s. The expression of the enzyme at mRNA level was down regulated during PPARα activation in liver, and we also found that the total Nudix hydrolase activity was decreased in rat liver peroxisomes isolated from clofibrate treated mice. These findings suggest that NUDT7α may be an important regulator of the peroxisomal CoASH pool, and likely also regulates the β-oxidation of fatty acids in the peroxisome at substrate leve

Dharmapummeja, mystiikkaa ja heroiinia : hengellinen murroskausi Yhdysvaltojen beat-kirjailijayhteisössä 1950- ja 1960-luvuilla

Tässä tutkielmassa tarkastelen 1950 ja 1960-luvuilla kirjoitetun yhdysvaltalaisen beat-kirjallisuuden kuvaa hengellisyydestä sekä mitä tämä kuvaus kertoo hengellisestä murroskaudesta aikakauden Yhdysvalloissa. Tutkielman tavoitteena on selvittää missä määrin ja millä tavoin beatit ja näiden kirjoittama kirjallisuus edustivat muutosta yhdysvaltalaisessa hengellisyydessä. Tutkielma edustaa kirjallisuuden antropologian historiallista suuntausta, jossa kirjallisia tekstejä luetaan etnografisena lähdemateriaalina. Tutkielman lähteenä on laaja määrä beat-kirjailijoiden 1950- ja 1960-luvulla kirjoittamia runokokoelmia ja romaaneja. Näiden teosten sisältämiä hengellisyyden kuvauksia analysoin Mary Bucholtzin ja Kira Hallin esittämän sosiolingvistisen metodin avulla. Tutkielman tärkein teoreettinen viitekehys on Marshall Sahlinsin teoria kulttuurisesta muutoksesta kulttuuristen kategorioiden ja näiden suhteiden muutoksena. Tutkielmassa esitän, että huolimatta sen heterogeenisyydestä beatien hengellisyyttä yhdistää kokemuksellisuuden vahva korostus, erilaisten visioiden ja näkyjen esiintyminen, uudenlaisen amerikkalaisuuden rakentaminen, transgressiivisuus sekä marginaaliryhmiin kuuluvien ihmisten asettaminen hengellisiin rooleihin. Tämän lisäksi esitän, että beatit edustivat murrosta yhdysvaltalaisessa hengellisyydessä johtuen erityisesti siitä, että beat-teksteissä hengellisyys yhdistyy uudella tavalla normien rikkomiseen ja vapauden tavoitteluun. Tutkielmassa esitän kuitenkin myös, että kyseessä ei ole täydellinen irtiotto. Beatit ovat selvästi osa yhdysvaltalaista hengellistä perinnettä, nojaten aikaisemmista ajatussuunnista erityisesti transsendentalismiin

Specific language impairment (SLI) at 11–12 years of age : Multiple case study focused on language functioning of monolingual and multilingual Finnish children

Tavoitteet. Kielellinen erityisvaikeus (SLI) on oirekuvaltaan heterogeeninen ja kehityksen myötä muuttuva häiriö. Useimmilla se vaikuttaa laaja-alaisesti toimintakykyyn, osallistumiseen ja oppimiseen. Oireet ovat pysyviä etenkin niillä, joilla on todettu puheen ymmärtämisen vaikeuksia. Usean kielen samanaikainen omaksuminen lisää kielellisten vaikeuksien yksilöllistä vaihtelua. Suomalaisten yli 10-vuotiaiden yksi- ja monikielisten SLI-lasten kielellistä toimintakykyä ei ole juurikaan tutkittu. Tämän tutkimuksen tavoitteena oli kuvata SLI:n ilmenemistä 11–12-vuotiailla yksi- ja monikielisillä lapsilla. Tutkimuksessa tarkastellaan tutkittavien kielellistä toimintakykyä ja koettua elämänlaatua. Niiden kuvaaminen voi edesauttaa tukitoimien kehittämistä. Menetelmät. Tutkittavina oli neljä 11–12-vuotiasta pääkaupunkiseudulla asuvaa poikaa, jotka olivat saaneet SLI-diagnoosin F80.2 Helsingin yliopistollisen keskussairaalan foniatrian yksikössä. Kaksi tutkittavista oli yksikielisiä ja kaksi monikielisiä, jotka oppivat suomea toisena kielenään. Tutkimuksen aineisto koostui kielellisistä testeistä sekä kyselyistä, joiden vastaajina olivat vanhemmat, opettajat ja tutkittavat. Testaukset videoitiin ja kerronta-aineisto litteroitiin. Aineisto analysoitiin tarkastelemalla suoriutumista suhteessa ikänormeihin ja aiempiin tutkimuksiin. Kyselyvastauksia analysoitiin lisäksi ryhmittelemällä vastausten sisältöjä ja tarkastelemalla niitä laadullisesti. Testisuoriutumista ja kyselyistä saatuja tietoja vertailtiin toisiinsa. Lisäksi tutkittavien kielellisessä toimintakyvyssä todettuja eroja pohdittiin tarkastelemalla lapsuudessa tehtyjä potilasasiakirjoja retrospektiivisesti. Tulokset ja johtopäätökset. Kaikkien tutkittavien kielellisessä toimintakyvyssä oli puutteita, mutta oirekuva, sosiaalinen toimintakyky, koulusuoriutuminen ja koettu elämänlaatu vaihtelivat yksilöllisesti. Tulokset olivat samansuuntaisia aiempien tutkimusten kanssa. Vaikeuksia oli erityisesti kieliopin hallinnassa, lukemistaidoissa, lyhytkestoisessa kuulomuistissa ja nimeävässä sanavarastossa. Arjessa toimintakykyä heikensivät lisäksi puheen vastaanoton, kerronnan, pragmatiikan sekä osalla sosiaalisen vuorovaikutuksen vaikeudet. Monikielisten tutkittavien suomenkielisen sanaston hallinta oli yksikielisiä heikompaa. Muilta osin erot olivat suurempia yksilö- kuin ryhmätasolla. Kolmella tutkittavalla oli edelleen merkittävät tukitoimet koulussa; neljännellä niitä oli purettu suotuisan etenemisen vuoksi. Enemmistö koki terveyteen liittyvän elämänlaatunsa kokonaisuutena hieman verrokkeja heikommaksi. Saatujen tulosten perusteella pragmaattisten taitojen tukemiseen tulee kiinnittää erityistä huomiota kouluikäisillä, sillä aiempien tutkimusten mukaan ne vaikuttavat sosiaaliseen integroitumiseen. Aiheesta tarvitaan lisää tutkimusta suuremmalla otoksella sekä pitkittäisasetelmalla.Objectives. Specific language impairment (SLI) is a heterogeneous disorder and its symptoms change with development. For most people it has a profound effect on functional ability, participation, and learning. The symptoms are persistent especially among those with difficulties in speech-reception. Simultaneous learning of multiple languages increases the individual variation in linguistic difficulties. Language functioning of Finnish monolingual and multilingual children at age over 10 years has not been thoroughly investigated. The objective of this study was to describe how SLI manifests itself in 11–12-years-old monolingual and multilingual children. The study focused on language ability and health-related quality of life. The acquired information may help in improving supporting practices. Methods. Four male participants at age of 11–12 years living in the Capital Region of Finland, and with SLI diagnosis (F80.2) were recruited from Helsinki University Central Hospital Audiophoniatric ward 22 for the study. Two participants were monolingual and two were multilingual learning Finnish as their second language. The gathered data consisted of language tests and questionnaires intended for parents, teachers, and the participants. Testing was videotaped and the acquired narratives were transcribed. Results were compared against age norms as well as previous literature. Furthermore, the questionnaire data were grouped based on the content, and the results were analyzed qualitatively. In addition, the test results and questionnaire data were compared to each other. Finally, the differences in language abilities were examined in relation to medical reports written before school age. Results and conclusions. All participants had deficiencies in language abilities, but language symptoms, social ability, academic achievement, and quality of life varied individually. Results were in line with previous studies. Difficulties were observed especially in grammatical and reading abilities, short-term memory and word naming. Moreover, according to parents and teachers, the participants had problems in speech reception, narration, pragmatics, and some of them also in social interactions. Finnish vocabulary among the multilingual participants was smaller than that of their monolingual counterparts. However, differences in other areas were larger at single-level than at group-level. Three of the participants still received substantial support in school. Support of the fourth participant had been discontinued due to favorable progress. Majority of the participants perceived their health-related quality of life slightly weaker than that of controls. Based on the results, it is important to support pragmatic skills at school age since previous studies have shown an association of these to social integration. A Study with a larger sample size and longitudinal setting is needed in the future