Helsingin yliopiston tutkijoiden julkaisemia artikkeleja.

Helsingin yliopiston tutkijat voivat rinnakkaistallentaa tutkimusjulkaisujansa HELDAan liittämällä kokotekstin julkaisuun TUHAT-tutkimustietojärjestelmässä. (Toimintaohje tutkijalle)


Uusimmat julkaisut

  • Brenner, Stephan; Mazalale, Jacob; Wilhelm, Danielle; Nesbitt, Robin C; Lohela, Terhi J; Chinkhumba, Jobiba; Lohmann, Julia; Muula, Adamson S; De Allegri, Manuela (BioMed Central, 2018)
    Abstract Background Results-based financing (RBF) describes health system approaches addressing both service quality and use. Effective coverage is a metric measuring progress towards universal health coverage (UHC). Although considered a means towards achieving UHC in settings with weak health financing modalities, the impact of RBF on effective coverage has not been explicitly studied. Methods Malawi introduced the Results-Based Financing For Maternal and Neonatal Health (RBF4MNH) Initiative in 2013 to improve quality of maternal and newborn health services at emergency obstetric care facilities. Using a quasi-experimental design, we examined the impact of the RBF4MNH on both crude and effective coverage of pregnant women across four districts during the two years following implementation. Results There was no effect on crude coverage. With a larger proportion of women in intervention areas receiving more effective care over time, the overall net increase in effective coverage was 7.1%-points (p = 0.07). The strongest impact on effective coverage (31.0%-point increase, p = 0.02) occurred only at lower cut-off level (60% of maximum score) of obstetric care effectiveness. Design-specific and wider health system factors likely limited the program’s potential to produce stronger effects. Conclusion The RBF4MNH improved effective coverage of pregnant women and seems to be a promising reform approach towards reaching UHC. Given the short study period, the full potential of the current RBF scheme has likely not yet been reached.
  • Korpela, Katri; Salonen, Anne; Vepsäläinen, Outi; Suomalainen, Marjo; Kolmeder, Carolin; Varjosalo, Markku; Miettinen, Sini; Kukkonen, Kaarina; Savilahti, Erkki; Kuitunen, Mikael; de Vos, Willem M (BioMed Central, 2018)
    Abstract Background Infants born by caesarean section or receiving antibiotics are at increased risk of developing metabolic, inflammatory and immunological diseases, potentially due to disruption of normal gut microbiota at a critical developmental time window. We investigated whether probiotic supplementation could ameliorate the effects of antibiotic use or caesarean birth on infant microbiota in a double blind, placebo-controlled randomized clinical trial. Mothers were given a multispecies probiotic, consisting of Bifidobacterium breve Bb99 (Bp99 2 × 108 cfu) Propionibacterium freundenreichii subsp. shermanii JS (2 × 109cfu), Lactobacillus rhamnosus Lc705 (5 × 109 cfu) and Lactobacillus rhamnosus GG (5 × 109 cfu) (N = 168 breastfed and 31 formula-fed), or placebo supplement (N = 201 breastfed and 22 formula-fed) during pregnancy, and the infants were given the same supplement. Faecal samples of the infants were collected at 3 months and analyzed using taxonomic, metagenomic and metaproteomic approaches. Results The probiotic supplement had a strong overall impact on the microbiota composition, but the effect depended on the infant’s diet. Only breastfed infants showed the expected increase in bifidobacteria and reduction in Proteobacteria and Clostridia. In the placebo group, both birth mode and antibiotic use were significantly associated with altered microbiota composition and function, particularly reduced Bifidobacterium abundance. In the probiotic group, the effects of antibiotics and birth mode were either completely eliminated or reduced. Conclusions The results indicate that it is possible to correct undesired changes in microbiota composition and function caused by antibiotic treatments or caesarean birth by supplementing infants with a probiotic mixture together with at least partial breastfeeding. Trial registration NCT00298337 . Registered March 2, 2006.
  • Pänkäläinen, Mikko; Fogelholm, Mikael; Valve, Raisa; Kampman, Olli; Kauppi, Markku; Lappalainen, Erja; Hintikka, Jukka (BioMed Central, 2018)
    Abstract Background Dietary habits have a great influence on physiological health. Even though this fact is generally recognized, people do not eat as healthily as they know they should. The factors that support a healthy diet, on the other hand, are not well known. It is supposed that there is a link between personal traits and dietary habits. Personal traits may also partially explain why some people manage to make healthy dietary changes while some fail to do so or are not able to try to make changes even when they desire to do so. There is some information suggesting that dispositional optimism plays a role in succeeding in improving dietary habits. The aim of this study was to determine the role of optimism and pessimism in the process of dietary changes. Methods Dispositional optimism and pessimism were determined using the revised Life Orientation Test in 2815 individuals (aged 52–76 years) participating in the GOAL study in the region of Lahti, Finland. The dietary habits of the study subjects were analysed. After 3 years, the subjects’ dietary habits and their possible improvements were registered. The associations between dispositional optimism and pessimism, dietary habits at baseline, and possible changes in dietary habits during the follow-up were studied with logistic regression. We also studied if the dietary habits or certain lifestyle factors (e.g. physical exercising and smoking) at baseline predicted success in improving the diet. Results Pessimism seemed to correlate clearly negatively with the healthiness of the dietary habits at baseline – i.e. the higher the level of pessimism, the unhealthier the diet. Optimism also showed a correlation with dietary habits at baseline, although to a lesser extent. Those who managed to improve their dietary habits during follow-up or regarded their dietary habits as healthy enough even without a change were less pessimistic at baseline than those who failed in their attempts to improve their diet or did not even try, even when they recognized the need for a change. Conclusions Pessimistic people are more likely to eat an unhealthy diet than others. Pessimism reduces independently the possibilities to improve dietary patterns.
  • Heliste, Juho; Jokilammi, Anne; Paatero, Ilkka; Chakroborty, Deepankar; Stark, Christoffer; Savunen, Timo; Laaksonen, Maria; Elenius, Klaus (BioMed Central, 2018)
    Abstract Background Receptor tyrosine kinases (RTK) are potential targets for the treatment of ischemic heart disease. The human RTK family consists of 55 members, most of which have not yet been characterized for expression or activity in the ischemic heart. Methods RTK gene expression was analyzed from human heart samples representing healthy tissue, acute myocardial infarction or ischemic cardiomyopathy. As an experimental model, pig heart with ischemia-reperfusion injury, caused by cardiopulmonary bypass, was used, from which phosphorylation status of RTKs was assessed with a phospho-RTK array. Expression and function of one RTK, ROR1, was further validated in pig tissue samples, and in HL-1 cardiomyocytes and H9c2 cardiomyoblasts, exposed to hypoxia and reoxygenation. ROR1 protein level was analyzed by Western blotting. Cell viability after ROR1 siRNA knockdown or activation with Wnt-5a ligand was assessed by MTT assays. Results In addition to previously characterized RTKs, a group of novel active and regulated RTKs was detected in the ischemic heart. ROR1 was the most significantly upregulated RTK in human ischemic cardiomyopathy. However, ROR1 phosphorylation was suppressed in the pig model of ischemia-reperfusion and ROR1 phosphorylation and expression were down-regulated in HL-1 cardiomyocytes subjected to short-term hypoxia in vitro. ROR1 expression in the pig heart was confirmed on protein and mRNA level. Functionally, ROR1 activity was associated with reduced viability of HL-1 cardiomyocytes in both normoxia and during hypoxia-reoxygenation. Conclusions Several novel RTKs were found to be regulated in expression or activity in ischemic heart. ROR1 was one of the most significantly regulated RTKs. The in vitro findings suggest a role for ROR1 as a potential target for the treatment of ischemic heart injury.
  • Tsai, Pei-Chien; Glastonbury, Craig A; Eliot, Melissa N; Bollepalli, Sailalitha; Yet, Idil; Castillo-Fernandez, Juan E; Carnero-Montoro, Elena; Hardiman, Thomas; Martin, Tiphaine C; Vickers, Alice; Mangino, Massimo; Ward, Kirsten; Pietiläinen, Kirsi H; Deloukas, Panos; Spector, Tim D; Viñuela, Ana; Loucks, Eric B; Ollikainen, Miina; Kelsey, Karl T; Small, Kerrin S; Bell, Jordana T (BioMed Central, 2018)
    Abstract Background Tobacco smoking is a risk factor for multiple diseases, including cardiovascular disease and diabetes. Many smoking-associated signals have been detected in the blood methylome, but the extent to which these changes are widespread to metabolically relevant tissues, and impact gene expression or metabolic health, remains unclear. Methods We investigated smoking-associated DNA methylation and gene expression variation in adipose tissue biopsies from 542 healthy female twins. Replication, tissue specificity, and longitudinal stability of the smoking-associated effects were explored in additional adipose, blood, skin, and lung samples. We characterized the impact of adipose tissue smoking methylation and expression signals on metabolic disease risk phenotypes, including visceral fat. Results We identified 42 smoking-methylation and 42 smoking-expression signals, where five genes (AHRR, CYP1A1, CYP1B1, CYTL1, F2RL3) were both hypo-methylated and upregulated in current smokers. CYP1A1 gene expression achieved 95% prediction performance of current smoking status. We validated and replicated a proportion of the signals in additional primary tissue samples, identifying tissue-shared effects. Smoking leaves systemic imprints on DNA methylation after smoking cessation, with stronger but shorter-lived effects on gene expression. Metabolic disease risk traits such as visceral fat and android-to-gynoid ratio showed association with methylation at smoking markers with functional impacts on expression, such as CYP1A1, and at tissue-shared smoking signals, such as NOTCH1. At smoking-signals, BHLHE40 and AHRR DNA methylation and gene expression levels in current smokers were predictive of future gain in visceral fat upon smoking cessation. Conclusions Our results provide the first comprehensive characterization of coordinated DNA methylation and gene expression markers of smoking in adipose tissue. The findings relate to human metabolic health and give insights into understanding the widespread health consequence of smoking outside of the lung.
  • Wallström, Peter; Drake, Isabel; Sonestedt, Emily; Gullberg, Bo; Bjartell, Anders; Olsson, Håkan; Adlercreutz, Herman; Tikkanen, Matti J.; Wirfält, Elisabet (2018)
    Enterolactone (ENL) is formed in the human gut after consumption of lignans, has estrogenic properties, and has been associated with risk of prostate cancer. We examined the association between plasma ENL levels and prostate cancer in a nested case-control study within the population-based Malmo Diet and Cancer cohort. We also examined the association between plasma ENL and dietary and lifestyle factors. The study population consisted of 1010 cases occurring during a mean follow-up of 14.6 years, and 1817 controls matched on age and study entry date. We used national registers (95%) and hospital records (5%) to ascertain cases. Diet was estimated by a modified diet history method. Plasma ENL concentrations were determined by a time-resolved fluoroimmunoassay. Odds ratios were calculated by unconditional logistic regression. There were no significant associations between plasma ENL and incidence of all prostate cancer (odds ratio 0.99 [95% confidence interval 0.77-1.280] for the highest ENL quintile versus lowest, p for trend 0.66). However, in certain subgroups of men, including men with abdominal obesity (p for interaction = 0.012), we observed associations between high ENL levels and lower odds of high-risk prostate cancer. Plasma ENL was positively associated with consumption of high-fibre bread, fruit, tea, and coffee; with age, and with height, while it was negatively associated with smoking and waist circumference; however, although significant, all associations were rather weak (r ae |0.14|). ENL concentration was not consistently associated with lower prostate cancer risk, although it was weakly associated with a healthy lifestyle.
  • Matikainen, M.; Aro, E.; Vironen, J.; Kössi, J.; Hulmi, T.; Silvasti, S.; Ilves, I.; Hertsi, M.; Mustonen, K.; Paajanen, H. (2018)
    Chronic pain after inguinal hernioplasty is the foremost side-effect up to 10-30% of patients. Mesh fixation may influence on the incidence of chronic pain after open anterior mesh repairs. Some 625 patients who underwent open anterior mesh repairs were randomized to receive one of the three meshes and fixations: cyanoacrylate glue with low-weight polypropylene mesh (n = 216), non-absorbable sutures with partially absorbable mesh (n = 207) or self-gripping polyesther mesh (n = 202). Factors related to chronic pain (visual analogue scores; VAS ae 30, range 0-100) at 1 year postoperatively were analyzed using logistic regression method. A second analysis using telephone interview and patient records was performed 2 years after the index surgery. At index operation, all patient characteristics were similar in the three study groups. After 1 year, chronic inguinal pain was found in 52 patients and after 2 years in only 16 patients with no difference between the study groups. During 2 years' follow-up, three (0.48%) patients with recurrences and five (0.8%) patients with chronic pain were re-operated. Multivariate regression analysis indicated that only new recurrent hernias and high pain scores at day 7 were predictive factors for longstanding groin pain (p = 0.001). Type of mesh or fixation, gender, pre-operative VAS, age, body mass index or duration of operation did not predict chronic pain. Only the presence of recurrent hernia and early severe pain after index operation seemed to predict longstanding inguinal pain.
  • Hyytiäinen, Heli K.; Mölsä, Sari H.; Junnila, Jouni J. T.; Laitinen-Vapaavuori, Outi M.; Hielm-Björkman, Anna K. (2018)
    This study aimed at developing a quantitative testing battery for dogs' stifle functionality, as, unlike in human medicine, currently none is available in the veterinary field. Forty-three dogs with surgically treated unilateral cranial cruciate ligament rupture and 21 dogs with no known musculoskeletal problems were included. Eight previously studied tests: compensation in sitting and lying positions, symmetry of thrust in hindlimbs when rising from lying and sitting, static weight bearing, stifle flexion and extension and muscle mass symmetry, were summed into the Finnish Canine Stifle Index (FCSI). Sensitivities and specificities of the dichotomised FCSI score were calculated against orthopaedic examination, radiological and force platform analysis and a conclusive assessment (combination of previous). One-way analysis of variance (ANOVA)was used to evaluate FCSI score differences between the groups. Cronbach's alpha for internal consistency was calculated. The range of the index score was 0-263, with a proposed cut-off value of 60 between 'adequate' and 'compromised' functional performance. In comparison to the conclusive assessment, the sensitivity and specificity of the FCSI were 90 per cent and 90.5 per cent, respectively. Cronbach's alpha for internal reliability of the FCSI score was 0.727. An estimate of the surgically treated and control dogs' FCSI scores were 105 (95 per cent CI 93 to 116) and 20 (95 per cent CI 4 to 37), respectively. The difference between the groups was significant (P
  • Mattila, K.; Haas, M.; Haikala, L. K.; Jo, Y-S.; Lehtinen, K.; Leinert, Ch.; Väisänen, P. (2018)
    Context. Dark nebulae display a surface brightness because dust grains scatter light of the general interstellar radiation field (ISRF). High-galactic-latitudes dark nebulae are seen as bright nebulae when surrounded by transparent areas which have less scattered light from the general galactic dust layer. Aims. Photometry of the bright dark nebulae LDN 1780, LDN 1642, and LBN 406 shall be used to derive scattering properties of dust and to investigate the presence of UV fluorescence emission by molecular hydrogen and the extended red emission (ERE). Methods. We used multi-wavelength optical photometry and imaging at ground-based telescopes and archival imaging and spectroscopic UV data from the spaceborn GALEX and SPEAR/FIMS instruments. In the analysis we used Monte Carlo RT and both observational data and synthetic models for the ISRF in the solar neighbourhood. The line-of-sight extinctions through the clouds have been determined using near infrared excesses of background stars and the 200/250 mu m far infrared emission by dust as measured using the ISO and Herschel space observatories. Results. The optical surface brightness of the three target clouds can be explained in terms of scattered light. The dust albedo ranges from similar to 0.58 at 3500 angstrom to similar to 0.72 at 7500 angstrom. The spectral energy distribution of LDN 1780 is explained in terms of optical depth and background scattered light effects instead of the original published suggestion in terms of ERE. The far-ultraviolet surface brightness of LDN 1780 cannot be explained by scattered light only. In LDN 1780, H-2 fluorescent emission in the wavelength range 1400-1700 angstrom has been detected and analysed. Conclusions. Our albedo values are in good agreement with the predictions of the dust model of Weingartner and Draine and with the THEMIS CMM model for evolved core-mantle grains. The distribution of H-2 fluorescent emission in LDN 1780 shows a pronounced dichotomy with a strong preference for its southern side where enhanced illumination is impinging from the Sco OB2 association and the O star zeta Oph. A good correlation is found between the H-2 fluorescence and a previously mapped 21-cm excess emission. The H-2 fluorescence emission in LDN 1780 has been modelled using a PDR code; the resulting values for H-2 column density and the total gas density are consistent with the estimates derived from CO observations and optical extinction along the line of sight.
  • Koponen, Juhani (Manchester University Press, 2014)
    Studies in Imperialism
    Shows the variety of meanings of development in South-Eastern Tanganyika during the period concerned and spells out their implications for the history of development more generally
  • Hokynar, Kati; Salava, Alexander; Vesterinen, Eero; Lauerma, Antti; Ranki, Annamari; Puolakkainen, Mirja (2018)
  • Evangelou, Evangelos; Warren, Helen R.; Mosen-Ansorena, David; Mifsu, Borbala; Pazoki, Raha; Gao, He; Ntritsos, Georgios; Dimou, Niki; Cabrer, Claudia P.; Karaman, Ibrahim; Ng, FuLiang; Evangelou, Marina; Witkowska, Katarzyna; Tzanis, Evan; Hellwege, Jacklyn N.; Giri, Ayush; Edwards, Digna R. Velez; Sun, Yan; Cho, Kelly; Gaziano, J. Michael; Wilson, Peter W. F.; Tsao, Philip S.; Kovesdy, Csaba P.; Esko, Tonu; Magi, Reedik; Milani, Lili; Almgren, Peter; Boutin, Thibaud; Debette, Stephanie; Ding, Jun; Giulianini, Franco; Holliday, Elizabeth G.; Jackson, Anne U.; Li-Gao, Ruifang; Lin, Wei-Yu; Luan, Jian'an; Mangino, Massimo; Oldmeadow, Christopher; Prins, Bram Peter; Qian, Yong; Sargurupremraj, Muralidharan; Shah, Nabi; Havulinna, Aki S.; Jousilahti, Pekka; Kristiansson, Kati; Palotie, Aarno; Perola, Markus; Ripatti, Samuli; Sarin, Antti-Pekka; Tuomilehto, Jaakko (2018)
    High blood pressure is a highly heritable and modifiable risk factor for cardiovascular disease. We report the largest genetic association study of blood pressure traits (systolic, diastolic and pulse pressure) to date in over 1 million people of European ancestry. We identify 535 novel blood pressure loci that not only offer new biological insights into blood pressure regulation but also highlight shared genetic architecture between blood pressure and lifestyle exposures. Our findings identify new biological pathways for blood pressure regulation with potential for improved cardiovascular disease prevention in the future.
  • Soukkio, Paula; Suikkanen, Sara; Kääriä, Sanna; Kautiainen, Hannu; Sipilä, Sarianna; Kukkonen-Harjula, Katriina; Hupli, Markku (2018)
    Background: Health concerns, such as frailty and osteoporotic fractures decrease functional capacity and increase use of health and social care services in the aging population. The ability to continue living at home is dependent on functional capacity, which can be enhanced by rehabilitation. We study the effects of a 12-month home-based physiotherapy program with 12-month follow-up on duration of living at home, functional capacity, and the use of social and health care services among older persons with signs of frailty, or with a recently operated hip fracture. Methods: This is a non-blinded, parallel group, randomized controlled trial performed in South Karelia Social and Health Care District, Finland (population 131,000). Three hundred community-dwelling older persons with signs of frailty (age >= 65) and 300 persons with a recent hip fracture (age >= 60) will be recruited. Frailty is screened by FRAIL questionnaire and verified by modified Fried's frailty criteria. Both patient groups will be randomized separately to a physiotherapy and a usual care arm. Individualized, structured and progressive physiotherapy will be carried out for 60 min, twice a week for 12 months at the participant's home. The primary outcome at 24 months is duration of living at home. Our hypothesis is that persons assigned to the physiotherapy arm will live at home for six months longer than those in the usual care arm. Secondary outcomes are functional capacity, frailty status, health-related quality-of-life, falls, use and costs of social and health care services, and mortality. Assessments, among others Short Physical Performance Battery, Functional Independence Measure, Mini Nutritional Assessment, and Mini-Mental State Examination will be performed at the participant's home at baseline, 3, 6, and 12 months. Register data on the use and costs of social and health care services, and mortality will be monitored for 24 months. Discussion: Our trial will provide new knowledge on the potential of intensive, long-term home-based physiotherapy among older persons at risk for disabilities, to enhance functional capacity and thereby to postpone the need for institutional care, and diminish the use of social and health care services.
  • Jääskeläinen, Tiina; Kärkkäinen, Olli; Jokkala, Jenna; Litonius, Kaisa; Heinonen, Seppo; Auriola, Seppo; Lehtonen, Marko; Hanhineva, Kati; Laivuori, Hannele (2018)
    Preeclampsia (PE) is a complex pregnancy disorder. It is not extensively known how the metabolic alterations of PE women contribute to the metabolism of newborn. We applied liquid chromatography-mass spectrometry (LC-MS) based non-targeted meta bolomics to determine whether the metabolic profile of plasma from umbilical cord differs between infants born to PE and non-PE pregnancies in the FINNPEC study. Cord plasma was available from 42 newborns born from PE and 53 from non-PE pregnancies. 133 molecular features differed between PE and non-PE newborns after correction for multiple testing. Decreased levels of 4-pyridoxic acid were observed in the cord plasma samples of PE newborns when compared to non-PE newborns. Compounds representing following areas of metabolism were increased in the cord plasma of PE newborns: urea and creatine metabolism; carnitine biosynthesis and acylcarnitines; putrescine metabolites; tryptophan metabolism and phosphatidylcholines. To our knowledge, this study is the first one to apply LC-MS based meta bolomics in cord plasma of PE newborns. We demonstrate that this strategy provides a global picture of the widespread metabolic alterations associated with PE and particularly the elevated levels of carnitine precursors and trimethylated compounds appear to be associated with PE at birth.
  • GPrank 
    Topa, Hande; Honkela, Antti (2018)
    Background: Genome-wide high-throughput sequencing (HIS) time series experiments are a powerful tool for monitoring various genomic elements over time. They can be used to monitor, for example, gene or transcript expression with RNA sequencing (RNA-seq), DNA methylation levels with bisulfite sequencing (BS-seq), or abundances of genetic variants in populations with pooled sequencing (Pool-seq). However, because of high experimental costs, the time series data sets often consist of a very limited number of time points with very few or no biological replicates, posing challenges in the data analysis. Results: Here we present the GPrank R package for modelling genome-wide time series by incorporating variance information obtained during pre-processing of the HIS data using probabilistic quantification methods or from a beta-binomial model using sequencing depth. GPrank is well-suited for analysing both short and irregularly sampled time series. It is based on modelling each time series by two Gaussian process (GP) models, namely, time-dependent and time-independent GP models, and comparing the evidence provided by data under two models by computing their Bayes factor (BF). Genomic elements are then ranked by their BFs, and temporally most dynamic elements can be identified. Conclusions: Incorporating the variance information helps GPrank avoid false positives without compromising computational efficiency. Fitted models can be easily further explored in a browser. Detection and visualisation of temporally most active dynamic elements in the genome can provide a good starting point for further downstream analyses for increasing our understanding of the studied processes.
  • Almangush, Alhadi; Mäkitie, Antti A.; Mäkinen, Laura K.; Kauppila, Joonas H.; Pukkila, Matti; Hagström, Jaana; Laranne, Jussi; Soini, Ylermi; Kowalski, Luiz Paulo; Grenman, Reidar; Haglund, Caj; Coletta, Ricardo D.; Salo, Tuula; Leivo, Ilmo (2018)
    One of the main changes in the 8th edition of the American Joint Committee on Cancer (AJCC) for staging of oral cancer is the inclusion of depth of invasion (DOI) in the T category. However, cancers in different oral subsites have variable behavior, with oral tongue squamous cell carcinoma (OTSCC) being the most aggressive one even at early stage. Thus, it is necessary to evaluate the performance of this new T category in homogenous cohort of early OTSCC. Therefore, we analyzed a large cohort of patients with a small (ae4 cm) OTSCC to demonstrate the differences in T stage between the AJCC 7th and 8th editions. A total of 311 early-stage cases (AJCC 7th) of OTSCC were analyzed. We used 5 mm and 10 mm DOI for upstaging from T1 to T2 and from T2 to T3 respectively, as in the AJCC 8th. We further reclassified the cases according to our own proposal suggesting 2 mm to upstage to T2 and 4 mm to upstage to T3. According to AJCC 7th, there were no significant differences in the survival analysis. When we applied the 8th edition, many cases were upstaged to T3 and thus associated with worse disease-specific survival (HR 2.37, 95% CI 1.12-4.99) and disease-free survival (HR 2.12, 95% CI 1.09-4.08). Based on our proposal, T3 cases were associated with even worse disease-specific survival (HR 4.19, 95% CI 2.27-7.74). The 8th edition provides better survival prediction for OTSCC than the 7th and can be further optimized by lowering the DOI cutoffs.
  • Droste, Nils; D'Amato, Dalia; Goddard, Jessica J. (2018)
    We analyze how the content of ecosystem service research has evolved since the early 1990s. Conducting a computational bibliometric content analysis we process a corpus of 14,118 peer-reviewed scientific article abstracts on ecosystem services (ES) from Web of Science records. To provide a comprehensive content analysis of ES research literature, we employ a latent Dirichlet allocation algorithm. For three different time periods (1990-2000, 2001-2010, 2011-2016), we derive nine main ES topics arising from content analysis and elaborate on how they are related over time. The results show that natural science-based ES research analyzes oceanic, freshwater, agricultural, forest, and soil ecosystems. Pollination and land cover emerge as traceable standalone topics around 2001. Social science ES literature demonstrates a reflexive and critical lens on the role of ES research and includes critiques of market-oriented perspectives. The area where social and natural science converge most is about land use systems such as agriculture. Overall, we provide evidence of the strong natural science foundation, the highly interdisciplinary nature of ES research, and a shift in social ES research towards integrated assessments and governance approaches. Furthermore, we discuss potential reasons for observable topic developments.
  • Kämäräinen, A.; Simojoki, A.; Linden, L.; Jokinen, K.; Silvan, N. (2018)
    The surface biomass of moss dominated by Sphagnum fuscum (Schimp.) Klinggr. (Rusty Bog-moss) was harvested from a sparsely drained raised bog. Physical properties of the Sphagnum moss were determined and compared with those of weakly and moderately decomposed peats. Water retention curves (WRC) and saturated hydraulic conductivities (K-s) are reported for samples of Sphagnum moss with natural structure, as well as for samples that were cut to selected fibre lengths or compacted to different bulk densities. The gravimetric water retention results indicate that, on a dry mass basis, Sphagnum moss can hold more water than both types of peat under equal matric potentials. On a volumetric basis, the water retention of Sphagnum moss can be linearly increased by compacting at a gravimetric water content of 2 (g water / g dry mass). The bimodal water retention curve of Sphagnum moss appears to be a consequence of the natural double porosity of the moss matrix. The 6-parameter form of the double-porosity van Genuchten equation is used to describe the volumetric water retention of the moss as its bulk density increases. Our results provide considerable insight into the physical growing media properties of Sphagnum moss biomass.
  • Rosa, Elena; Woestmann, Luisa; Biere, Arjen; Saastamoinen, Marjo (2018)
    Host plant chemical composition critically shapes the performance of insect herbivores feeding on them. Some insects have become specialized on plant secondary metabolites, and even use them to their own advantage such as defense against predators. However, infection by plant pathogens can seriously alter the interaction between herbivores and their host plants. We tested whether the effects of the plant secondary metabolites, iridoid glycosides (IGs), on the performance and immune response of an insect herbivore are modulated by a plant pathogen. We used the IG-specialized Glanville fritillary butterfly Melitaea cinxia, its host plant Plantago lanceolata, and the naturally occurring plant pathogen, powdery mildew Podosphaera plantaginis, as model system. Pre-diapause larvae were fed on P. lanceolata host plants selected to contain either high or low IGs, in the presence or absence of powdery mildew. Larval performance was measured by growth rate, survival until diapause, and by investment in immunity. We assessed immunity after a bacterial challenge in terms of phenoloxidase (PO) activity and the expression of seven pre-selected insect immune genes (qPCR). We found that the beneficial effects of constitutive leaf IGs, that improved larval growth, were significantly reduced by mildew infection. Moreover, mildew presence downregulated one component of larval immune response (PO activity), suggesting a physiological cost of investment in immunity under suboptimal conditions. Yet, feeding on mildew-infected leaves caused an upregulation of two immune genes, lysozyme and prophenoloxidase. Our findings indicate that a plant pathogen can significantly modulate the effects of secondary metabolites on the growth of an insect herbivore. Furthermore, we show that a plant pathogen can induce contrasting effects on insect immune function. We suspect that the activation of the immune system toward a plant pathogen infection may be maladaptive, but the actual infectivity on the larvae should be tested.
  • Hellen, Heidi; Praplan, Arnaud P.; Tykkä, Toni; Ylivinkka, Ilona; Vakkari, Ville; Bäck, Jaana; Petäjä, Tuukka; Kulmala, Markku; Hakola, Hannele (2018)
    The concentrations of terpenoids (isoprene; monoterpenes, MTs; and sesquiterpenes, SQTs) and oxygenated volatile organic compounds (OVOCs; i.e. aldehydes, alcohols, acetates and volatile organic acids, VOAs) were investigated during 2 years at a boreal forest site in Hyytiala, Finland, using in situ gas chromatograph mass spectrometers (GC-MSs). Seasonal and diurnal variations of terpenoid and OVOC concentrations as well as their relationship with meteorological factors were studied. Of the VOCs examined, C-2-C-7 unbranched VOAs showed the highest concentrations, mainly due to their low reactivity. Of the terpenoids, MTs showed the highest concentrations at the site, but seven different highly reactive SQTs were also detected. The monthly and daily mean concentrations of most terpenoids, aldehydes and VOAs were highly dependent on the temperature. The highest exponential correlation with temperature was found for a SQT (beta-caryophyllene) in summer. The diurnal variations in the concentrations could be explained by sources, sinks and vertical mixing. The diurnal variations in MT concentrations were strongly affected by vertical mixing. Based on the temperature correlations and mixing layer height (MLH), simple proxies were developed for estimating the MT and SQT concentrations. To estimate the importance of different compound groups and compounds in local atmospheric chemistry, reactivity with main oxidants (hydroxyl radical, OH; nitrate radical, NO3; and ozone, O-3) and production rates of oxidation products (OxPRs) were calculated. The MTs dominated OH and NO3 radical chemistry, but the SQTs greatly impacted O-3 chemistry, even though the concentrations of SQT were 30 times lower than the MT concentrations. SQTs were also the most important for the production of oxidation products. Since the SQTs show high secondary organic aerosol (SOA) yields, the results clearly indicate the importance of SQTs for local SOA production.

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