Impact of dibenzocyclooctadiene lignans from Schisandra chinensis on the redox status and activation of human innate immune system cells

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DNA barcoding and LC-MS metabolite profiling of the lichen-forming genus Melanelia: Specimen identification and discrimination focusing on Icelandic taxa

Taxa in the genus Melanelia (Parmeliaceae, Ascomycota) belong to a group of saxicolous lichens with brown to black foliose thalli, which have recently undergone extensive changes in circumscription. Taxa belonging to Parmeliaceae are prolific producers of bioactive compounds, which have also been traditionally used for chemotaxonomic purposes. However, the chemical diversity of the genus Melanelia and the use of chemical data for species discrimination in this genus are largely unexplored. In addition, identification based on morphological characters is challenging due to few taxonomically informative characters. Molecular identification methods, such as DNA barcoding, have rarely been applied to this genus. This study aimed to identify the Melanelia species from Iceland using DNA barcoding approach, and to explore their chemical diversity using chemical profiling. Chemometric tools were used to see if lichen metabolite profiles determined by LC-MS could be used for the identification of Icelandic Melanelia species. Barcoding using the fungal nuclear ribosomal internal transcribed spacer region (nrITS) successfully identified three Melalenlia species occurring in Iceland, together with Montanelia disjuncta (Basionym: Melanelia disjuncta). All species formed monophyletic clades in the neighbor-joining nrITS gene tree. However, high intraspecific genetic distance of M. stygia suggests the potential of unrecognized species lineages. Principal component analysis (PCA) of metabolite data gave a holistic overview showing that M. hepatizon and M. disjuncta were distinct from the rest, without the power to separate M. agnata and M. stygia due to their chemical similarity. Orthogonal partial least–squares to latent structures–discriminate analysis (OPLS-DA), however, successfully distinguished M. agnata and M. stygia by identifying statistically significant metabolites, which lead to class differentiation. This work has demonstrated the potential of DNA barcoding, chemical profiling and chemometrics in identification of Melanelia species.The study was financially supported by the People Programme (Marie Curie Actions) of the European Union’s Seventh Framework Programme FP7/2007-2013/ under REA grant agreement No. 606895 (http://cordis.europa.eu/project/rcn/109122_en.html) as well as a minor contribution from Bergthora and Thorsteinn Scheving Thorsteinsson Fund. The funders provided support in the form of salaries for author [MX], but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of this author is articulated in the ‘author contributions’ section. The commercial affiliation Arctic Mass has no financial or competing interests in this study but two of the authors MT and FFE are partially affiliated there. Arctic Mass had the role of providing access to instruments (mass spectrometers) used in the study.Peer Reviewe

The Genus Diphasiastrum and Its Lycopodium Alkaloids

Publisher's version (útgefin grein)The genus Diphasiastrum includes at least 23 species distributed primarily across the northern temperate and subarctic areas of the world. These plants produce an array of lycopodium alkaloids, and some species such as Diphasiastrum complanatum have been used in traditional medicine for ages for various conditions. Hybridization is common in this group of plants and they have always been a challenge for taxonomists and other scientists studying them. To date, 11 Diphasiastrum species have been reported to produce lycopodium alkaloids. In this review, reported alkaloids and their distribution patterns across these species along with taxonomical and bioactivity considerations are reviewed and discussed.This work was supported by The Icelandic Research Fund, The University of Iceland Research Fund, and The Eimskip Fund of the University of Iceland.Peer Reviewe

Authentication of Iceland Moss (Cetraria islandica) by UPLC-QToF-MS chemical profiling and DNA barcoding

The lichen Cetraria islandica or Iceland Moss is commonly consumed as tea, food ingredients (e.g. in soup or bread) and herbal medicines. C. islandica, which has two chemotypes, can be difficult to distinguish from the sister species Cetraria ericetorum. They are collectively referred to as the Cetraria islandica species complex. This study aimed to use an UPLC-QToF-MS chemical profiling together with DNA barcoding to distinguish species and chemotypes of the C. islandica species complex. Our results show that the two chemotypes of C. islandica are clearly distinguishable from each other and from C. ericetorum by the chemometric approach. The RPB2 barcode was able to differentiate C. islandica from C. ericetorum with a barcode gap, but the widely used nrITS barcode failed. Neither of them could discriminate chemotypes of C. islandica. In conclusion, this integrative approach involving chemical profiling and DNA barcoding could be applied for authentication of Iceland Moss materials

A Comparison of Fresh and Frozen Lamb Meat-Differences in Technological Meat Quality and Sensory Attributes

Simple Summary Freezing is used to extend the storage time of meat and is common practice in lamb meat production, since it maintains a steady supply of seasonal meat throughout the year and allows shipping over long distances. Fresh meat may also be purchased and frozen at home, to enable longer storage of the product before consumption. Freezing is the best preservation method, apart from chilling of fresh meat. However, differences in quality parameters between fresh and frozen meat may influence consumer choice and preferences. It is thus important to evaluate these differences, and how they are affected by conditions and animal handling during primary production, slaughter method and storage conditions before retail sale. This study examined the effect of freezing on technological meat quality and sensory attributes in lamb meat samples collected at two different slaughterhouses using different slaughter methods. Several differences between fresh and frozen-thawed meat were detected in terms of technological meat quality and sensory attributes, including colour, Warner-Bratzler shear force, cooking loss, flavour attributes and juicy texture. Technological meat quality and sensory attributes of fresh and frozen lamb meat were compared. Samples were collected from two abattoirs (one small-scale, one large-scale) that use different slaughter methods in terms of chilling regime and electrical stimulation. The fresh and frozen meat samples included products from both slaughter systems. Ten twin pairs of ram lambs were used in the study, with one of each twin slaughtered at each abattoir. Fresh meat was analysed after chilling and frozen meat was stored frozen for three months and analysed after thawing. The Musculus longissimus thoracis et lumborum was analysed for colour, cooking loss, sensory attributes, Warner-Bratzler shear force (WBSF) and distribution of water and lipid within each meat sample. Meat samples analysed after frozen storage were darker, less red and more yellow than the fresh meat. Freezing and frozen storage increased fluid loss and WBSF compared with the fresh meat, due to protein denaturation. Frozen storage affected sensory attributes by increasing fatty odour, frying flavour, sour flavour, fatty flavour and liver flavour, and by reducing juicy texture and mushy texture

Prevalence of Helicobacter pylori in HIV-infected, HAART-naïve Ugandan children: a hospital-based survey

<p>Abstract</p> <p>Background</p> <p>The aim of this survey was to determine the prevalence of and factors associated with <it>Helicobacter pylori </it>(<it>H. pylori</it>) colonization in HIV-infected, highly active antiretroviral therapy-naïve Ugandan children aged 0-12 years.</p> <p>Methods</p> <p>In a hospital-based survey, 236 HIV-infected children were tested for <it>H. pylori </it>colonization using a faecal antigen test. A standardized interview with socio-demographic information and medical history was used to assess risk factors. A cluster of differentiation 4 (CD4) cell percentage was prevalent in most children.</p> <p>Results</p> <p>The overall prevalence of <it>H. pylori </it>in the HIV-infected children was 22.5%. Age-specific prevalence was as follows: up to one year, 14.7%; 1-3 years, 30.9%; and 3-12 years, 20.7%. HIV-infected children who were more seriously affected by their disease (low CD4 cell percentage or WHO clinical stage II-IV) were less likely to be colonized with <it>H. pylori</it>. There was a trend for a lower prevalence of <it>H. pylori </it>in children who had taken antibiotics for the preceding two weeks (21.6%) than in those who had not taken antibiotics (35.7%). There was no statistically significant difference in prevalence by gender, housing, congested living, education of the female caretaker, drinking water or toilet facilities.</p> <p>Conclusions</p> <p>HIV-infected, HAART-naïve Ugandan children had a lower prevalence of <it>H. pylori </it>colonization compared with apparently healthy Ugandan children (44.3%). Children with a low CD4 cell percentage and an advanced clinical stage of HIV had an even lower risk of <it>H. pylori </it>colonization. Treatment with antibiotics due to co-morbidity with infectious diseases is a possible explanation for the relatively low prevalence.</p

Similar decline in mortality rate of older persons with and without type 2 diabetes between 1993 and 2004 the Icelandic population-based Reykjavik and AGES-Reykjavik cohort studies.

To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked Files. This article is open access.A decline in mortality rates due to cardiovascular diseases and all-cause mortality has led to increased life expectancy in the Western world in recent decades. At the same time, the prevalence of type 2 diabetes, a disease associated with a twofold excess risk of cardiovascular disease and mortality, has been increasing. The objective of this study was to estimate the secular trend of cardiovascular and all-cause mortality rates in two population-based cohorts of older persons, with and without type 2 diabetes, examined 11 years apart.1506 participants (42% men) from the population-based Reykjavik Study, examined during 1991-1996 (median 1993), mean age 75.0 years, and 4814 participants (43% men) from the AGES-Reykjavik Study, examined during 2002-2006 (median 2004), mean age 77.2 years, age range in both cohorts 70-87 years. The main outcome measures were age-specific mortality rates due to cardiovascular disease and all causes, over two consecutive 5.7- and 5.3-year follow-up periods.A 32% decline in cardiovascular mortality rate and a 19% decline in all-cause mortality rate were observed between 1993 and 2004. The decline was greater in those with type 2 diabetes, as illustrated by the decline in the adjusted hazard ratio of cardiovascular mortality in individuals with diabetes compared to those without diabetes, from 1.88 (95% CI 1.24-2.85) in 1993 to 1.46 (95% CI 1.11-1.91) in 2004. We also observed a concurrent decrease in major cardiovascular risk factors in both those with and without diabetes. A higher proportion of persons with diabetes received glucose-lowering, hypertensive and lipid-lowering medication in 2004.A decline in cardiovascular and all-cause mortality rates was observed in older persons during the period 1993-2004, in both those with and without type 2 diabetes. This decline may be partly explained by improvements in cardiovascular risk factors and medical treatment over the period studied. However, type 2 diabetes still persists as an independent risk factor for cardiovascular mortality.National Institute of Health/N01-AG-1-2100 NIA Intramural Research Program Icelandic Heart Association (Hjartavernd) Icelandic Parliament (Althingi

Phylogenetic diversity of the lichenized algal genus Trebouxia (Trebouxiophyceae, Chlorophyta): a new lineage and novel insights from fungal-algal association patterns of Icelandic cetrarioid lichens (Parmeliaceae, Ascomycota)

Publisher's version (útgefin grein)Lichens have high tolerance to harsh environmental conditions, where lichen symbiont interactions (e.g. myco- and photobionts) may play a crucial role. The characterization of fungal-algal association patterns is essential to understand their symbiotic interactions. This study investigated fungal-algal association patterns in Icelandic cetrarioid lichens using a multi-locus phylogenetic framework, including fungal nrITS, MCM7, mtSSU, RPB1 and RPB2 and algal nrITS, nrLSU, rbcL and mtCOXII data. Most Icelandic cetrarioid lichenized fungi were found to be specifically associated to the known Trebouxia clade “S” (Trebouxia simplex/suecica group), whereas the lichen-forming fungus Cetrariella delisei forms a symbiosis with a previously unrecognized lineage of Trebouxia, provisionally named as the “D” clade. This new Trebouxia lineage is supported by maximum likelihood and Bayesian phylogenetic analyses using all four included algal loci.This project was supported by the European Union’s Seventh Framework Programme for research, technological development and demonstration (grant agreement number 606895) to FP7-MCA-ITN MedPlant, “Phylogenetic Exploration of Medicinal Plant Diversity”. The Icelandic Research Fund (grant number 185442051) and the Bergthora and Thorsteinn Scheving Thorsteinsson Fund are also acknowledged for financial support.Peer Reviewe

Liquefaction Assessment of a Loose Silty Sand Site in the 2008 Mw 6.3 Ölfus Earthquake

Seismicity in Iceland is related to the Mid-Atlantic plate boundary and primarily consolidated in two complex fracture zones. Liquefaction was observed after the Mw 6.3 Ölfus earthquake in 2008 at the site Arnarbaeli. The site consists of a thick silty sand stratum on the banks of the estuary of the river Ölfusa, and it is located less than 10 km from the earthquake epicentre. Based on nearby time history registrations, the estimated acceleration at the site was 0.6 - 0.7g. Using a simplified method, the safety factor against liquefaction based on the equivalent linear (EL) approach has been estimated. The analysis is built on in-situ field test data (i.e., MASW, and SPT). The analysis reveals the liquefaction depth, 4.4 m. It is shown that not only the current procedure is capable of predicting the occurrence of liquefaction, but also the safety factor which is in good agreement with the observed surface evidence of liquefaction at the site.This work was supported by the Icelandic Research Fund (Rannis), Grants number: 206793-052 and 218149-051.Peer Reviewe

Effects of statin medication on mortality risk associated with type 2 diabetes in older persons: the population-based AGES-Reykjavik Study

To access publisher full text version of this article. Please click on the hyperlink in Additional Links field.OBJECTIVE: To examine if the beneficial effect of statin medication on mortality seen in randomised clinical trials of type 2 diabetes applies equally to observational studies in the general population of older people. DESIGN: A prospective, population-based cohort study. SETTING: Reykjavik, Iceland. PARTICIPANTS: 5152 men and women from the Age, Gene/Environment Susceptibility-Reykjavik Study, mean age 77 years, range of 66-96 years. MAIN OUTCOME MEASURE: Cardiovascular and all-cause mortalities and the RR of dying according to statin use and history of coronary heart disease (CHD) in persons with type 2 diabetes and those without diabetes with a median follow-up time of 5.3 years, until end of 2009. RESULTS: The prevalence of type 2 diabetes was 12.4% of which 35% used statins. Statin use was associated with a 50% (95% CI 8% to 72%) lower cardiovascular mortality and 53% (29% to 68%) lower all-cause mortalities in persons with diabetes. For those without diabetes, statin use was associated with a 16% (-24% to 43%) lower cardiovascular and 30% (11% to 46%) lower all-cause mortalities. Persons with diabetes using statins had a comparable risk of cardiovascular and all-cause mortality to that of the general population without diabetes. The effect was independent of the level of glycaemic control. CONCLUSION: This observational study lends important support to existing data from randomised clinical trials. These data suggest that in the general population of older people with diabetes, statin medication markedly reduces the excess cardiovascular and all-cause mortality risk, irrespective of the presence or absence of coronary heart disease or glucose-lowering medication