Composition of Hawthorn (Crataegus spp.) Fruits and Leaves and emblic Leafflower (Phyllanthus emblica) Fruits

Hawthorn (Crataegus sp.) is widely distributed in the northern hemisphere (Asia, Europe and North America). It has been used as a medicinal material and food for hundreds of years both in Europe and in China. Clinical investigations and other research suggest that extracts of hawthorn fruits and leaves have multiple health effects including hypolipidaemic, anti-atherosclerotic, hypotensive, cardioprotective and blood vessel relaxing activities. Hawthorn fruit extracts have also displayed antioxidant and radical scavenging activities. Emblic leafflower fruit (Phyllanthus emblica) is widely used in Chinese and Indian traditional medicine. It has been found to have anti-cancer, hypoglycaemic and hypolipidaemic activities as well as cardioprotective effects and antioxidant activity. The fruit is currently used as a functional food targeted at obese people in China. Phenolic compounds, procyanidins (PCs), flavonols and C-glycosyl flavones in hawthorn and hydrolysable tannins in emblic leafflower fruits are considered among the major bioactive compounds in these berries. Moreover, hawthorn and emblic leafflower fruits are rich in vitamin C, triterpenoids, fruit acids, sugar alcohols and some other components with beneficial effects on the health of human beings. The aim of the thesis work was to characterise the major phenolic compounds in hawthorn fruits and leaves and emblic leafflower fruits as well as other components contributing to the nutritional profile and sensory properties of hawthorn fruits. Differences in the content and compositional profile of the major phenolic compounds, sugars, acids and sugar alcohols within various origins and species of hawthorn were also investigated. Acids, sugars and sugar alcohols in the fruits of different origins/cultivars belonging to three species (C. pinnatifida, C. brettschneideri and C. scabrifolia) of hawthorn were analysed by gas chromatography (GC-FID) and mass spectrometry (Publication I). Citric acid, quinic acid, malic acid, fructose, glucose, sorbitol and myo-inositol were found in all the subspecies. Sucrose was present only in C. scabrifolia and three cultivars of C. pinnatifida var. major. Forty-two phenolic compounds were identified/tentatively identified in fruits of C. pinnatifida var. major by polyamide column chromatography combined with high-performance liquid chromatograph-electrospray ionisation mass spectrometry (HPLC-ESI-MS) (Publication II). Ideain, chlorogenic acid, procyanidin (PC) B2, (-)-epicatechin, hyperoside and isoquercitrin were the major phenolic components identified. In addition, 35 phenolic compounds were tentatively identified based on UV and mass spectra. Eleven major phenolic compounds (hyperoside, isoquercitrin, chlorogenic acid, ideain, (-)-epicatechin, two PC dimers, three PC trimers and a PC dimer-hexoside) were quantified in the fruits of 22 cultivars/origins of three species of Chinese hawthorn by HPLC-ESI-MS with single ion recording function (SIR) (Publication III). The fruits of the hawthorn cultivars/origins investigated fell into two groups, one rich in sugars and flavonols, the other rich in acids and procyanidins. Based on the compositional features, different biological activities and sensory properties may be expected between cultivars/origins of the two groups. The results suggest that the contents of phenolic compounds, acids, sugars and sugar alcohols may be used as chemotaxonomic information distinguishing the hawthorn species from each other. Phenolic compounds in fruits and leaves of C. grayana and their changes during fruit ripening/harvesting were investigated using HPLC-UV-ESI-MS (Publication IV). (-)-Epicatechin, PC B2 and C1, hyperoside and a quercetin-pentoside were the major phenolic compounds in both fruits and leaves. Three C-glycosyl flavones (a luteolin-C-hexoside, a methyl luteolin-C-hexoside and an apigenin-C-hexoside) were present in leaves in abundance, but only at trace levels in fruits. Ideain and 5-O-caffeoylquinic acid were found in fruits only. Additionally, eleven phenolic compounds were identified/tentatively identified in both leaves and fruits (three B-type PC trimers, two B-type PC tetramers, a quercetin-rhamnosylhexoside, a quercetin-pentoside, a methoxykaempferol-methylpentosylhexoside, a quercetin-hexoside acetate, a methoxykaempferol-pentoside, chlorogenic acid and an unknown hydroxycinnamic acid derivative). The total content of phenolic compounds reached the highest level by the end of August in fruits and by the end of September in leaves. The compositional profiles of phenolic compounds in fruits and leaves of C. grayana were different from those of C. pinnatifida, C. brettschneideri, C. scabrifolia, C. pinnatifida. var. major, C. monogyna, C. laevigata and C. pentagyna. Phenolic compounds in emblic leafflower fruits were characterised by Sephadex LH-20 column chromatography combined with HPLC-ESI-MS (Publication V). A mucic acid gallate, three isomers of mucic acid lactone gallate, a galloylglucose, gallic acid, a digalloylglucose, putranjivain A, a galloyl-HHDP-glucose, elaeocarpusin and chebulagic acid represented the major phenolic compounds in fruits of emblic leafflower. In conclusion, results of this study significantly increase the current knowledge on the key bioactive and nutritional components of hawthorn and emblic leafflower fruits. These results provide important information for research on the mechanism responsible for the health benefits of these fruits.

Flavonoids and other phenolic compounds: characterization and interactions with lepidopteran and sawfly larvae

This thesis focuses on flavonoids, a subgroup of phenolic compounds produced by plants, and how they affect the herbivorous larvae of lepidopterans and sawflies. The first part of the literature review examines different techniques to analyze the chemical structures of flavonoids and their concentrations in biological samples. These techniques include, for example, ultraviolet-visible spectroscopy, mass spectrometry, and nuclear magnetic resonance spectroscopy. The second part of the literature review studies how phenolic compounds function in the metabolism of larvae. The harmful oxidation reactions of phenolic compounds in insect guts are also emphasized. In addition to the negative effects, many insect species have evolved the use of phenolic compounds for their own benefit. In the experimental part of the thesis, high concentrations of complex flavonoid oligoglycosides were found in the hemolymph (the circulatory fluid of insects) of birch and pine sawflies. The larvae produced these compounds from simple flavonoid precursors present in the birch leaves and pine needles. Flavonoid glycosides were also found in the cocoon walls of sawflies, which suggested that flavonoids were used in the construction of cocoons. The second part of the experimental work studied the modifications of phenolic compounds in conditions that mimicked the alkaline guts of lepidopteran larvae. It was found that the 24 plant species studied and their individual phenolic compounds had variable capacities to function as oxidative defenses in alkaline conditions. The excrements of lepidopteran and sawfly species were studied to see how different types of phenolics were processed by the larvae. These results suggested that phenolic compounds were oxidized, hydrolyzed, or modified in other ways during their passage through the digestive tract of the larvae.

Kuntouttavan työn kehitysmahdollisuudet ja taloudelliset vaikutukset metsäteollisuusyrityksessä

Metsäteollisuudessa henkilöstön keski-ikä on monen muun toimialan tavoin noussut merkittävästi viime vuosina. Samaan aikaan työt ovat monipuolistuneet, ja henkilöstöä on vähennetty kustannustehokkuuden nimissä. Osittain näiden tekijöiden seurauksena sairauspoissaolot ovat nousseet, ja niiden aiheuttamat kustannukset ovat vuosittain hyvin merkittävät. Lisäksi työkyvyttömyys- ja tapaturmaeläköitymisten kustannukset ovat keskimäärin nousseet uuden maksuluokkajärjestelmän käyttöönoton myötä. Sairauspoissaolojen alentamisen ja eläköitymisten ehkäisemiseksi on vuosien varrella hyödynnetty erilaisia käytäntöjä ja toimintamalleja, joiden vaikutusalueet vaihtelevat työturvallisuudesta työhönpaluun tukemiseen. Erilaisia uudelleensijoituksia ja työtehtävien räätälöintejä on mahdollisuuksien mukaan pyritty toteuttamaan, mutta näiden esteenä on pääosin ollut yhteistyön ja tiedon puute, haastava ajankohta, sekä erilaiset negatiiviset asenteet. Kuntouttavalla työllä tarkoitetaan eri osapuolten kanssa yhdessä sovittua, määräaikaista ja normaalista poikkeavaa toimintaa, jolla pyritään vähentämään osatyökykyisen työntekijän pitkiä poissaoloja sekä poistamaan mahdollinen varhaisen eläköitymisen uhka. Tämän tutkimuksen aikana kehitetyn kuntouttavan työn uuden toimintamallin tavoitteena on edelleen lisätä tietoisuutta ja yhteistyötä eri osapuolten välillä sekä vaikuttaa omalta osaltaan työnantajan sairauspoissaolojen ja eläköitymisten aiheuttamiin kustannuksiin.

Potential of the Osteoclast’s Proton Pump as a Drug Target in Osteoporosis

Decreasing bone mass during aging predisposes to fractures and it is estimated that every second woman and one in five men will suffer osteoporotic fractures during their lifetime. Bone is an adaptive tissue undergoing continuous remodeling in response to physical and metabolic stimuli. Bone mass decreases through a net negative balance in the bone remodeling process of bone, in which the new bone incompletely replaces the resorbed bone mass. Bone resorption is carried out by the osteoclasts; the bone mineral is solubilized by acidification and the organic matrix is subsequently degraded by proteases. Several classes of drugs are available for prevention of osteoporotic fractures. They act by different mechanisms to increase bone mass, and some of them act mainly as antiresorptives by inhibition of osteoclast formation or their function. Optimally, a drug should act selectively on a specific process, since other processes affected usually result in adverse effects. The purpose of this study was to evaluate whether the osteoclastic vacuolar adenosine trisphosphatases (V-ATPase), which drives the solubilization of bone mineral, can be selectively inhibited despite its ubiquitous cellular functions. The V-ATPase is a multimeric protein composed of 13 subunits of which six possesses two or more isoforms. Selectivity for the osteoclastic V-ATPase could be provided if it has some structural uniqueness, such as a unique isoform combination. The a3 isoform of the 116kDa subunit is inevitable for bone resorption; however, it is also present in, and mainly limited to, the lysosomes of other cells. No evidence of a structural uniqueness of the osteoclastic V-ATPase compared to the lysosomal V-ATPase was found, although this can not yet be excluded. Thus, an inhibitor selective for the a3 isoform would target the lysosomal V-ATPase as well. However, the results suggest that selectivity for bone resorption over lysosomal function can be obtained by two other mechanisms, suggesting that isoform a3 is a valid target. The first is differential compensation; bone resorption depends on the high level of a3 expression, and is not compensated for by other isoforms, while the lower level of a3 in lysosomes of other cells may be partly compensated for. The second mechanism is because the bone resorption process itself is fundamentally different from lysosomal acidification because of the chemistry of bone dissolution and the anatomy of the resorbing osteoclast. By this mechanism, full inhibition of bone resorption is obtained with more than tenfold lower inhibitor concentration than those needed to fully inhibit lysosomal acidification. The two mechanisms are additive. Based on the results, we suggest that bone resorption can be selectively inhibited if VATPase inhibitors that are sufficiently selective for the a3 isoform over the other isoforms are developed.

Application of Computational Fluid Dynamics in Modeling Blood Flow in Human Thoracic Aorta

The aim of this study was to simulate blood flow in thoracic human aorta and understand the role of flow dynamics in the initialization and localization of atherosclerotic plaque in human thoracic aorta. The blood flow dynamics in idealized and realistic models of human thoracic aorta were numerically simulated in three idealized and two realistic thoracic aorta models. The idealized models of thoracic aorta were reconstructed with measurements available from literature, and the realistic models of thoracic aorta were constructed by image processing Computed Tomographic (CT) images. The CT images were made available by South Karelia Central Hospital in Lappeenranta. The reconstruction of thoracic aorta consisted of operations, such as contrast adjustment, image segmentations, and 3D surface rendering. Additional design operations were performed to make the aorta model compatible for the numerical method based computer code. The image processing and design operations were performed with specialized medical image processing software. Pulsatile pressure and velocity boundary conditions were deployed as inlet boundary conditions. The blood flow was assumed homogeneous and incompressible. The blood was assumed to be a Newtonian fluid. The simulations with idealized models of thoracic aorta were carried out with Finite Element Method based computer code, while the simulations with realistic models of thoracic aorta were carried out with Finite Volume Method based computer code. Simulations were carried out for four cardiac cycles. The distribution of flow, pressure and Wall Shear Stress (WSS) observed during the fourth cardiac cycle were extensively analyzed. The aim of carrying out the simulations with idealized model was to get an estimate of flow dynamics in a realistic aorta model. The motive behind the choice of three aorta models with distinct features was to understand the dependence of flow dynamics on aorta anatomy. Highly disturbed and nonuniform distribution of velocity and WSS was observed in aortic arch, near brachiocephalic, left common artery, and left subclavian artery. On the other hand, the WSS profiles at the roots of branches show significant differences with geometry variation of aorta and branches. The comparison of instantaneous WSS profiles revealed that the model with straight branching arteries had relatively lower WSS compared to that in the aorta model with curved branches. In addition to this, significant differences were observed in the spatial and temporal profiles of WSS, flow, and pressure. The study with idealized model was extended to study blood flow in thoracic aorta under the effects of hypertension and hypotension. One of the idealized aorta models was modified along with the boundary conditions to mimic the thoracic aorta under the effects of hypertension and hypotension. The results of simulations with realistic models extracted from CT scans demonstrated more realistic flow dynamics than that in the idealized models. During systole, the velocity in ascending aorta was skewed towards the outer wall of aortic arch. The flow develops secondary flow patterns as it moves downstream towards aortic arch. Unlike idealized models, the distribution of flow was nonplanar and heavily guided by the artery anatomy. Flow cavitation was observed in the aorta model which was imaged giving longer branches. This could not be properly observed in the model with imaging containing a shorter length for aortic branches. The flow circulation was also observed in the inner wall of the aortic arch. However, during the diastole, the flow profiles were almost flat and regular due the acceleration of flow at the inlet. The flow profiles were weakly turbulent during the flow reversal. The complex flow patterns caused a non-uniform distribution of WSS. High WSS was distributed at the junction of branches and aortic arch. Low WSS was distributed at the proximal part of the junction, while intermedium WSS was distributed in the distal part of the junction. The pulsatile nature of the inflow caused oscillating WSS at the branch entry region and inner curvature of aortic arch. Based on the WSS distribution in the realistic model, one of the aorta models was altered to induce artificial atherosclerotic plaque at the branch entry region and inner curvature of aortic arch. Atherosclerotic plaque causing 50% blockage of lumen was introduced in brachiocephalic artery, common carotid artery, left subclavian artery, and aortic arch. The aim of this part of the study was first to study the effect of stenosis on flow and WSS distribution, understand the effect of shape of atherosclerotic plaque on flow and WSS distribution, and finally to investigate the effect of lumen blockage severity on flow and WSS distributions. The results revealed that the distribution of WSS is significantly affected by plaque with mere 50% stenosis. The asymmetric shape of stenosis causes higher WSS in branching arteries than in the cases with symmetric plaque. The flow dynamics within thoracic aorta models has been extensively studied and reported here. The effects of pressure and arterial anatomy on the flow dynamic were investigated. The distribution of complex flow and WSS is correlated with the localization of atherosclerosis. With the available results we can conclude that the thoracic aorta, with complex anatomy is the most vulnerable artery for the localization and development of atherosclerosis. The flow dynamics and arterial anatomy play a role in the localization of atherosclerosis. The patient specific image based models can be used to diagnose the locations in the aorta vulnerable to the development of arterial diseases such as atherosclerosis.

[Kirja-arvostelu]

Kirjallisuusarvostelu

Functional Genomic Approaches for Deciphering Plant-Virus Interactions

Plant-virus interactions are very complex in nature and lead to disease and symptom formation by causing various physiological, metabolic and developmental changes in the host plants. These interactions are mainly the outcomes of viral hijacking of host components to complete their infection cycles and of host defensive responses to restrict the viral infections. Viral genomes contain only a small number of genes often encoding for multifunctional proteins, and all are essential in establishing a viral infection. Thus, it is important to understand the specific roles of individual viral genes and their contribution to the viral life cycles. Among the most important viral proteins are the suppressors of RNA silencing (VSRs). These proteins function to suppress host defenses mediated by RNA silencing and can also serve in other functions, e.g. in viral movement, transactivation of host genes, virus replication and protein processing. Thus these proteins are likely to have a significant impact on host physiology and metabolism. In the present study, I have examined the plant-virus interactions and the effects of three different VSRs on host physiology and gene expression levels by microarray analysis of transgenic plants that express these VSR genes. I also studied the gene expression changes related to the expression of the whole genome of Tobacco mosaic virus (TMV) in transgenic tobacco plants. Expression of the VSR genes in the transgenic tobacco plants causes significant changes in the gene expression profiles. HC-Pro gene derived from the Potyvirus Y (PVY) causes alteration of 748 and 332 transcripts, AC2 gene derived from the African cassava mosaic virus (ACMV) causes alteration of 1118 and 251transcripts, and P25 gene derived from the Potyvirus X (PVX) causes alterations of 1355 and 64 transcripts in leaves and flowers, respectively. All three VSRs cause similar up-regulation in defense, hormonally regulated and different stress-related genes and down-regulation in the photosynthesis and starch metabolism related genes. They also induce alterations that are specific to each viral VSR. The phenotype and transcriptome alterations of the HC-Pro expressing transgenic plants are similar to those observed in some Potyvirus-infected plants. The plants show increased protein degradation, which may be due to the HC-Pro cysteine endopeptidase and thioredoxin activities. The AC2-expressing transgenic plants show a similar phenotype and gene expression pattern as HC-Pro-expressing plants, but also alter pathways related to jasmonic acid, ethylene and retrograde signaling. In the P25 expressing transgenic plants, high numbers of genes (total of 1355) were up-regulated in the leaves, compared to a very low number of down-regulated genes (total of 5). Despite of strong induction of the transcripts, only mild growth reduction and no other distinct phenotype was observed in these plants. As an example of whole virus interactions with its host, I also studied gene expression changes caused by Tobacco mosaic virus (TMV) in tobacco host in three different conditions, i.e. in transgenic plants that are first resistant to the virus, and then become susceptible to it and in wild type plants naturally infected with this virus. The microarray analysis revealed up and down-regulation of 1362 and 1422 transcripts in the TMV resistant young transgenic plants, and up and down-regulation of a total of 1150 and 1200 transcripts, respectively, in the older plants, after the resistance break. Natural TMV infections in wild type plants caused up-regulation of 550 transcripts and down-regulation of 480 transcripts. 124 up-regulated and 29 down-regulated transcripts were commonly altered between young and old TMV transgenic plants, and only 6 up-regulated and none of the down-regulated transcripts were commonly altered in all three plants. During the resistant stage, the strong down-regulation in translation-related transcripts (total of 750 genes) was observed. Additionally, transcripts related to the hormones, protein degradation and defense pathways, cell division and stress were distinctly altered. All these alterations may contribute to the TMV resistance in the young transgenic plants, and the resistance may also be related to RNA silencing, despite of the low viral abundance and lack of viral siRNAs or TMV methylation activity in the plants.

Naisjohtajat – miksi heitä ei ole ja mitä siitä? - miesjohtajien ja ei-johtavassa asemassa olevien naisten näkemyksiä case-yritys x:ssä

Joidenkin tutkimusten mukaan naisten vähäinen määrä johdossa voi olla uhka organisaatiolle. Lasikattoilmiöllä tarkoitetaan naisten urakehityksen katkeamista tietylle tasolle ylimmän johdon alapuolelle ikään kuin naisten ja tuon ylimmän tason välissä olisi lasinen, näkymätön katto, sukupuolistereotypioiden muodostama este. Yksi yleinen lasikaton selitysten kolmijako on henkilökohtaiset, organisatoriset ja yhteiskunnalliset tekijät. (Lämsä & Hautala 2004, 252). Hoyt (2007, 270-278) tekee kolmijaon seuraavasti: inhimillinen pääoma, sukupuolierot ja ennakkoluulot. Yritys X:n keskijohdossa työskentelee yksi nainen, ylimmässä johdossa ei yhtäkään. Tutkimuksessa halu-taan selvittää miesjohtajien ja ei-johtavassa asemassa olevien naisten käsitystä siitä, onko yritys x:ssä lasi-kattoa, miksi naisjohtajia on niin vähän ja "mitä siitä" ts. onko mitään ongelmaa olemassakaan. Tässä tutkimuksessa pohditaan diskurssianalyysin keinoin, miten yritys X:ssä puhutaan naisjohtajuusaiheesta, millai-seksi sukupuolen merkitys työelämässä määritellään ja mitä ajatellaan naisten kykenevyydestä johtajiksi. Naturalisoiva diskurssi oli vahva niin miesjohtajien ja ei-johtavassa asemassa olevien naisten puheessa. Sen lisäksi hahmotellaan familistista, empiiristä, humanistista ja historiallista diskurssia naisjohtajuuspuheesta. Diskurssien yhteenkietominen hegemonisoimisstrategiana kuvaa tapaa, jolla palasia muista diskursseista käytetään tukemaan tiettyä toista diskurssia (Jokinen et al. 1993c, 95) Miesjohtajien puheessa naisten keskeiset, ominaisuudet - liiallinen tarkkuus ja huolellisuus yhdistettynä epävarmuuteen - ovat ongelmallisia johtajanuran kannalta. Jos näistä johtajuuden kannalta negatiivisista ominaisuuksista ei jostain syystä kuitenkaan muodostuisi uralla etenemisen estettä, äitiys ja perheellisyys "luonnollisesti" tekee tämän. Aiheet myös kietoutuvat yhteen: äitiys ja vastuu perheestä lisäävät naisten huolellisuutta, tarkkuutta ja epävarmuutta entisestään. Lisäksi äitiyslomat ja työhön käytettävissä oleva aika ja puut-tuva halu käyttää elämästä iso osa uranluomiseen ovat johtajaksi etenemisen esteitä. Miesjohtajien mukaan tämä on jossain määrin ongelma, kun heterogeenisyyttä johtamiseen kuitenkin tarvittaisiin, mutta loppujen lopuksi kuitenkin melko epäkiinnostava ja pieni ongelma; ongelma ei miesten mielestä johdu miesten tai yhteiskunnallisista asenteista, vaan naisista itsestään ja he tarvitsevat uralla edetäkseen tukea, rohkaisua ja henkilöstöpankkeja, joita miesjohtajat voivat tuottaa. Johtaminen ylipäänsä ei ole miesjohtajien mielestä hirveän kiinnostavaa. Jos naiset (kaikesta edellä sanotusta huolimatta) etenevät yritysten johtoon, eivät he tule siellä toimeen keskenään. Kaiken kaikkiaan koko naisjohtajuusaihe ei ole kovin kiinnostava ja naisjohtajuuden vähäisyyden (mahdollisen) ongelman ratkaisee aika uuden, tasa-arvoisemman sukupolven myötä. Naishaastateltujen näkökulmasta sen sijaan naisilla on pyrkyä johtotehtäviin - joskaan ei samassa määrin kuin miehillä. Naishaastateltujen mukaan miehet suosivat toisiaan työelämässä ja naiset kohtaavat asenteita, joita vastaan joutuvat taistelemaan ja tästä syystä johtajien joukossa on niin vähän naisia. Historialliset tekijät pitävät asenteita yllä. Perheellisyys on naisille suurempi uraeste kuin miehille, "luonnollisesti". Naishaastateltujen mielestä naisten vähäisyys johdossa on merkittävä ongelma, koska naisilla on erityislaatuisia ominaisuuksia, joista olisi hyötyä tehtävässä. Naishaastateltujen puheessa miesten ominaisuuksia vastaavasti vähäteltiin. Naisjohtajien vähäisyyden ongelmalle ei naishaastateltujen mielestä kuitenkaan ole tehtävissä paljonkaan: miesten ja yhteiskunnan asenteiden pitäisi muuttua, mutta keinoja tähän ei esitetä, sen sijaan naisten itsensä pitäisi vain "yrittää vielä kovemmin".