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Now showing items 21-40 of 1984
  • Kaasalainen, Ulla; Heinrichs, Jochen; Krings, Michael; Myllys, Leena; Grabenhorst, Heinrich; Rikkinen, Jouko; Schmidt, Alexander R. (Public Library of Science, 2015)
    One of the most important issues in molecular dating studies concerns the incorporation of reliable fossil taxa into the phylogenies reconstructed from DNA sequence variation in extant taxa. Lichens are symbiotic associations between fungi and algae and/or cyanobacteria. Several lichen fossils have been used as minimum age constraints in recent studies concerning the diversification of the Ascomycota. Recent evolutionary studies of Lecanoromycetes, an almost exclusively lichen-forming class in the Ascomycota, have utilized the Eocene amber inclusion Alectoria succinic as a minimum age constraint. However, a re-investigation of the type material revealed that this inclusion in fact represents poorly preserved plant remains, most probably of a root. Consequently, this fossil cannot be used as evidence of the presence of the genus Alectoria (Parmeliaceae, Lecanorales) or any other lichens in the Paleogene. However, newly discovered inclusions from Paleogene Baltic and Bitterfeld amber verify that alectorioid morphologies in lichens were in existence by the Paleogene. The new fossils represent either a lineage within the alectorioid group or belong to the genus Oropogon.
  • Tynkkynen, Veli-Pekka (Helsingin yliopisto, Aleksanteri-instituutti, 2015)
    Through its use of the Arctic, Russia tries to fortify the idea that it is a global Energy Superpower
  • Eranti, Veikko Oskari; Lonkila, Markku Kalle (FIRST MONDAY EDITORIAL GROUP, 2015)
    In this paper we study social aspects of using the Like button for purposes of impression management, identity construction, and maintenance of social ties online. On the theoretical level our investigation combines Goffman’s notion of face-work with concepts of social network analysis, shedding light on what we dub ‘nano-level’ interaction and sociality on social networking sites. Our data come from a 2013 classroom survey in which 26 Finnish university students were asked about their motives for and ways of using the Like button. Our results show that though the Like button was designed to allow users to express their positive evaluations of the contents of Facebook posts, comments, and pictures, it was in actual fact used for a wide variety of purposes, from dating efforts to conversation regulation and maintenance of social ties. Our results also reveal that the networked Facebook audience affects the users’ liking behavior, and that users reflect their liking based on previous likes.
  • Cousminer, Diana L.; Leinonen, Jaakko T.; Sarin, Antti-Pekka; Chheda, Himanshu; Surakka, Ida; Wehkalampi, Karoliina; Ellonen, Pekka; Ripatti, Samuli; Dunkel, Leo; Palotie, Aarno; Widen, Elisabeth (Public Library of Science, 2015)
    Constitutional delay of growth and puberty (CDGP) is the most common cause of pubertal delay. CDGP is defined as the proportion of the normal population who experience pubertal onset at least 2 SD later than the population mean, representing 2.3% of all adolescents. While adolescents with CDGP spontaneously enter puberty, they are at risk for short stature, decreased bone mineral density, and psychosocial problems. Genetic factors contribute heavily to the timing of puberty, but the vast majority of CDGP cases remain biologically unexplained, and there is no definitive test to distinguish CDGP from pathological absence of puberty during adolescence. Recently, we published a study identifying significant linkage between a locus at the pericentromeric region of chromosome 2 (chr 2) and CDGP in Finnish families. To investigate this region for causal variation, we sequenced chr 2 between the genomic coordinates of 79-124 Mb (genome build GRCh37) in the proband and affected parent of the 13 families contributing most to this linkage signal. One gene, DNAH6, harbored 6 protein-altering low-frequency variants (<6% in the Finnish population) in 10 of the CDGP probands. We sequenced an additional 135 unrelated Finnish CDGP subjects and utilized the unique Sequencing Initiative Suomi (SISu) population reference exome set to show that while 5 of these variants were present in the CDGP set, they were also present in the Finnish population at similar frequencies. Additional variants in the targeted region could not be prioritized for follow-up, possibly due to gaps in sequencing coverage or lack of functional knowledge of non-genic genomic regions. Thus, despite having a well-characterized sample collection from a genetically homogeneous population with a large population-based reference sequence dataset, we were unable to pinpoint variation in the linked region predisposing delayed puberty. This study highlights the difficulties of detecting genetic variants under linkage regions for complex traits and suggests that advancements in annotation of gene function and regulatory regions of the genome will be critical for solving the genetic background of complex phenotypes like CDGP.
    Idäntutkimus-lehden 2/2015 pääkirjoitus
  • Sennikov, Alexander N.; Barkworth, Mary E.; Welker, Cassiano A. D.; Prado, Jefferson (INTERNATIONAL ASSOCIATION FOR PLANT TAXONOMY, 2015)
  • Salonen, Minna K.; Wasenius, Niko; Kajantie, Eero; Lano, Aulikki; Lahti, Jari; Heinonen, Kati; Räikkönen, Katri; Eriksson, Johan G. (Public Library of Science, 2015)
    Objective Low physical activity (PA) is a major risk factor for cardiovascular and metabolic disorders in all age groups. We measured intensity and volume of PA and examined the associations between PA and the metabolic syndrome (MS), its components and body composition among young Finnish adults. Research Design and Methods The study comprises 991 men and women born 1985-86, who participated in a clinical study during the years 2009-11 which included assessments of metabolism, body composition and PA. Objectively measured (SenseWear Armband) five-day PA data was available from 737 participants and was expressed in metabolic equivalents of task (MET). Results The prevalence of MS ranged between 8-10%. Higher total mean volume (MET-hours) or intensity (MET) were negatively associated with the risk of MS and separate components of MS, while the time spent at sedentary level of PA was positively associated with MS. Conclusions MS was prevalent in approximately every tenth of the young adults at the age of 24 years. Higher total mean intensity and volume rates as well as longer duration spent at moderate and vigorous PA level had a beneficial impact on the risk of MS. Longer time spent at the sedentary level of PA increased the risk of MS.
  • Salo, Johanna; Andersson, Aino Maria Alice; Mikkola, Raimo Olavi; Kredics, Laszlo; Viljanen, Martti; Salkinoja-Salonen, Mirja Sinikka (2015)
    Penicillium expansum was identified as a major contaminant in indoor air, settled dust and materials of several buildings connected to indoor air related health complaints. This fungus emitted large quantities of exudates when cultivated on laboratory media. The exudates proved toxic towards four different mammalian test cells up to 10000 fold dilution. Toxins identified by LC-MS/MS were communesins and chaetoglobosin. Air dispersal of the toxic exudates was investigated with an experimental set-up where natural convection was generated by temperature gradient. It was found that the exudate with the contained toxins became airborne transported from the warmer surface to the colder surface. The results thus demonstrate transportation of microbially produced toxic substances across the air space. The role of liquid emissions from indoor molds represents a novel mechanism for human exposure in mold contaminated buildings. In this paper we report that vapor condensed from the indoor air of building affected with molds Aspergillus versicolor, Aspergillus calidoustus and Penicillium expansum contained substances that were acutely toxic when exposed to mammalian cells in vitro. The results encourage further study of condensed indoor water vapor as a tool to assess the presence of airborne substances with possible adverse health effects.
  • Lönnqvist, Jan-Erik; Hennig-Schmidt, Heike; Walkowitz, Gari (Public Library of Science, 2015)
  • Siljander, Pia Riitta-Maria; Yáñez-Mó, Maria (Co-Action Publishing, 2015)
    In the past decade, extracellular vesicles (EVs) have been recognized as potent vehicles of intercellular communication, both in prokaryotes and eukaryotes. This is due to their capacity to transfer proteins, lipids and nucleic acids, thereby influencing various physiological and pathological functions of both recipient and parent cells.While intensive investigation has targeted the role of EVs in different pathological processes, for example, in cancer and autoimmune diseases, the EV-mediated maintenance of homeostasis and the regulation of physiological functions have remained less explored. Here, we provide a comprehensive overview of the current understanding of the physiological roles of EVs, which has been written by crowd-sourcing, drawing on the unique EV expertise of academia-based scientists, clinicians and industry based in 27 European countries, the United States and Australia. This review is intended to be of relevance to both researchers already working on EV biology and to newcomers who will encounter this universal cell biological system. Therefore, here we address the molecular contents and functions of EVs in various tissues and body fluids from cell systems to organs. We also review the physiological mechanisms of EVs in bacteria, lower eukaryotes and plants to highlight the functional uniformity of this emerging communication system.
  • Forsberg, Simon K. G.; Kierczak, Marcin; Ljungvall, Ingrid; Merveille, Anne-Christine; Gouni, Vassiliki; Wiberg, Maria; Willesen, Jakob Lundgren; Hanas, Sofia; Lequarre, Anne-Sophie; Sorensen, Louise Mejer; Tiret, Laurent; McEntee, Kathleen; Seppälä, Eija; Koch, Jorgen; Battaille, Geraldine; Lohi, Hannes; Fredholm, Merete; Chetboul, Valerie; Haggstrom, Jens; Carlborg, Orjan; Lindblad-Toh, Kerstin; Hoglund, Katja (Public Library of Science, 2015)
    Diabetes mellitus is a serious health problem in both dogs and humans. Certain dog breeds show high prevalence of the disease, whereas other breeds are at low risk. Fructosamine and glycated haemoglobin (HbA1c) are two major biomarkers of glycaemia, where serum concentrations reflect glucose turnover over the past few weeks to months. In this study, we searched for genetic factors influencing variation in serum fructosamine concentration in healthy dogs using data from nine dog breeds. Considering all breeds together, we did not find any genome-wide significant associations to fructosamine serum concentration. However, by performing breed-specific analyses we revealed an association on chromosome 3 (rho(corrected) approximate to 1:68 x 10(-6)) in Belgian shepherd dogs of the Malinois subtype. The associated region and its close neighbourhood harbours interesting candidate genes such as LETM1 and GAPDH that are important in glucose metabolism and have previously been implicated in the aetiology of diabetes mellitus. To further explore the genetics of this breed specificity, we screened the genome for reduced heterozygosity stretches private to the Belgian shepherd breed. This revealed a region with reduced heterozygosity that shows a statistically significant interaction (rho = 0.025) with the association region on chromosome 3. This region also harbours some interesting candidate genes and regulatory regions but the exact mechanisms underlying the interaction are still unknown. Nevertheless, this finding provides a plausible explanation for breed-specific genetic effects for complex traits in dogs. Shepherd breeds are at low risk of developing diabetes mellitus. The findings in Belgian shepherds could be connected to a protective mechanism against the disease. Further insight into the regulation of glucose metabolism could improve diagnostic and therapeutic methods for diabetes mellitus.
  • Marjonen, Heidi; Sierra, Alejandra; Nyman, Anna; Rogojin, Vladimir; Grohn, Olli; Linden, Anni-Maija; Hautaniemi, Sampsa; Kaminen-Ahola, Nina (Public Library of Science, 2015)
    The adverse effects of alcohol consumption during pregnancy are known, but the molecular events that lead to the phenotypic characteristics are unclear. To unravel the molecular mechanisms, we have used a mouse model of gestational ethanol exposure, which is based on maternal ad libitum ingestion of 10% (v/v) ethanol for the first 8 days of gestation (GD 0.5-8.5). Early neurulation takes place by the end of this period, which is equivalent to the developmental stage early in the fourth week post-fertilization in human. During this exposure period, dynamic epigenetic reprogramming takes place and the embryo is vulnerable to the effects of environmental factors. Thus, we hypothesize that early ethanol exposure disrupts the epigenetic reprogramming of the embryo, which leads to alterations in gene regulation and life-long changes in brain structure and function. Genome-wide analysis of gene expression in the mouse hippocampus revealed altered expression of 23 genes and three miRNAs in ethanol-exposed, adolescent offspring at postnatal day (P) 28. We confirmed this result by using two other tissues, where three candidate genes are known to express actively. Interestingly, we found a similar trend of upregulated gene expression in bone marrow and main olfactory epithelium. In addition, we observed altered DNA methylation in the CpG islands upstream of the candidate genes in the hippocampus. Our MRI study revealed asymmetry of brain structures in ethanol-exposed adult offspring (P60): we detected ethanol-induced enlargement of the left hippocampus and decreased volume of the left olfactory bulb. Our study indicates that ethanol exposure in early gestation can cause changes in DNA methylation, gene expression, and brain structure of offspring. Furthermore, the results support our hypothesis of early epigenetic origin of alcohol-induced disorders: changes in gene regulation may have already taken place in embryonic stem cells and therefore can be seen in different tissue types later in life.
  • Laxström, Niklas; Giner, Pau; Thottingal, Santhosh (2015)
    Wikipedia exists in over 280 languages. The quality and quantity of articles in each language varies greatly. Translating from another Wikipedia is a natural way to add more content, but the translation process is not properly supported in the software used by Wikipedia. Past computer assisted translation tools built for Wikipedia (e.g. WikiBasha) are not commonly used. We created a new tool that adapts to the specific needs of an open community and the specifics of the kind of content in Wikipedia. Qualitative and quantitative data indicates that the new tool helps users to translate articles easier and faster.
  • Penttinen, Kirsi; Swan, Heikki; Vanninen, Sari; Paavola, Jere; Lahtinen, Annukka M.; Kontula, Kimmo; Aalto-Setala, Katriina (Public Library of Science, 2015)
    Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a highly malignant inherited arrhythmogenic disorder. Type 1 CPVT (CPVT1) is caused by cardiac ryanodine receptor (RyR2) gene mutations resulting in abnormal calcium release from sarcoplasmic reticulum. Dantrolene, an inhibitor of sarcoplasmic Ca2+ release, has been shown to rescue this abnormal Ca2+ release in vitro. We assessed the antiarrhythmic efficacy of dantrolene in six patients carrying various RyR2 mutations causing CPVT. The patients underwent exercise stress test before and after dantrolene infusion. Dantrolene reduced the number of premature ventricular complexes (PVCs) on average by 74% (range 33-97) in four patients with N-terminal or central mutations in the cytosolic region of the RyR2 protein, while dantrolene had no effect in two patients with mutations in or near the transmembrane domain. Induced pluripotent stem cells (iPSCs) were generated from all the patients and differentiated into spontaneously beating cardiomyocytes (CMs). The antiarrhythmic effect of dantrolene was studied in CMs after adrenaline stimulation by Ca2+ imaging. In iPSC derived CMs with RyR2 mutations in the N-terminal or central region, dantrolene suppressed the Ca2+ cycling abnormalities in 80% (range 65-97) of cells while with mutations in or near the transmembrane domain only in 23 or 32% of cells. In conclusion, we demonstrate that dantrolene given intravenously shows antiarrhythmic effects in a portion of CPVT1 patients and that iPSC derived CM models replicate these individual drug responses. These findings illustrate the potential of iPSC models to individualize drug therapy of inherited diseases.
  • Hästbacka, Johanna; Freden, Filip; Hult, Maarit; Bergquist, Maria; Wilkman, Erika; Vuola, Jyrki; Sorsa, Timo; Tervahartiala, Taina; Huss, Fredrik (Public Library of Science, 2015)
    Introduction Matrix metalloproteinases (MMPs) -8 and -9 are released from neutrophils in acute inflammation and may contribute to permeability changes in burn injury. In retrospective studies on sepsis, levels of MMP-8, MMP-9, and tissue inhibitor of metalloproteinase-1 (TIMP-1) differed from those of healthy controls, and TIMP-1 showed an association with outcome. Our objective was to investigate the relationship between these proteins and disease severity and outcome in burn patients. Methods In this prospective, observational, two-center study, we collected plasma samples from admission to day 21 post-burn, and burn blister fluid samples on admission. We compared MMP-8, -9, and TIMP-1 levels between TBSA20% (N = 30) injured patients and healthy controls, and between 90-day survivors and non-survivors. MMP-8, -9, and TIMP-1 levels at 24-48 hours from injury, their maximal levels, and their time-adjusted means were compared between groups. Correlations with clinical parameters and the extent of burn were analyzed. MMP-8, -9, and TIMP-1 levels in burn blister fluids were also studied. Results Plasma MMP-8 and -9 were higher in patients than in healthy controls (P20% groups. MMP-8 and -9 were not associated with clinical severity or outcome measures. TIMP-1 differed significantly between patients and controls (P20% groups (P
  • Arora, Tulika; Velagapudi, Vidya; Pournaras, Dimitri J.; Welbourn, Richard; le Roux, Carel W.; Oresic, Matej; Backhed, Fredrik (Public Library of Science, 2015)
    Roux-en-Y gastric bypass (RYGB) is an effective method to attain sustained weight loss and diabetes remission. We aimed to elucidate early changes in the plasma metabolome and lipidome after RYGB. Plasma samples from 16 insulin-resistant morbidly obese subjects, of whom 14 had diabetes, were subjected to global metabolomics and lipidomics analysis at pre-surgery and 4 and 42 days after RYGB. Metabolites and lipid species were compared between time points and between subjects who were in remission and not in remission from diabetes 2 years after surgery. We found that the variables that were most discriminatory between time points were decanoic acid and octanoic acid, which were elevated 42 days after surgery, and sphingomyelins (18:1/21:0 and 18:1/23:3), which were at their lowest level 42 days after surgery. Insulin levels were lower at 4 and 42 days after surgery compared with pre-surgery levels. At 4 days after surgery, insulin levels correlated positively with metabolites of branched chain and aromatic amino acid metabolism and negatively with triglycerides with long-chain fatty acids. Of the 14 subjects with diabetes prior to surgery, 7 were in remission 2 years after surgery. The subjects in remission displayed higher pre-surgery levels of tricarboxylic acid cycle intermediates and triglycerides with long-chain fatty acids compared with subjects not in remission. Thus, metabolic alterations are induced soon after surgery and subjects with diabetes remission differ in the metabolic profiles at pre- and early post-surgery time points compared to patients not in remission.
  • Prozorov, Sergei (BRILL, 2015)
    The article addresses the attempts of contemporary continental philosophy to develop a politics that would move beyond the Hobbesian logic of the constitution of political community. In their readings of Hobbes, Roberto Esposito and Giorgio Agamben emphasize the nihilistic character of Hobbes’s approach to community. For Esposito, Hobbes’s commonwealth is legitimized by a prior negation of the originary human community in the construction of the state of nature as the state of war. Yet, as Agamben shows, this negative state of nature is never fully transcended by the commonwealth, which persistently reproduces it in the state of exception. These critiques emphasize the complex relation between nature and artifice in Hobbes’s thought, which have profound implications for the attempts to arrive at a ‘post-Hobbesian’ mode of political community. Neither a facile search for a truer, more fundamental state of nature nor an affirmation of artifice and denaturation as constitutive of human community are sufficient to evade the Hobbesian constellation. A genuine move beyond Hobbes would rather consist in thoroughly deactivating the very relation between nature and artifice whereby they become indistinct and no longer negate each other.
  • Lindström, Jan Krister; Auer, Peter (University of Bayreuth, 2015)
    In this paper, we argue that the suggested mirror-equivalence of ‘left-’ and ‘right-’ adjoined or -positioned constituents in syntax is misleading from the point of view of Interac-tional Linguistics and needs to be replaced by a positionally sensitive grammatical analysis, in which pre- and post-positioning is seen in the context of the sequential unfolding of conversa-tion in time. We show this on the basis of various examples from conversational German and Swedish. Our main empirical focus is on pre- and post-positioned verba sentiendi expressions of the type ich denke… or jag tror (cf. English ‘I think’). A quantitative analysis shows that these expressions have an uneven distribution in pre- and post-position, as well as in different discourse genres. In a sequential analysis, we can see a positionally sensitive differentiation with respect to syntactic integration and interactional meaning, especially with reference to the dynamics of stance taking and turn taking.