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  • Lindström, M.; Korkeala, H. (American Society for Microbiology, 2006)
    Botulism is a potentially lethal paralytic disease caused by botulinum neurotoxin. Human pathogenic neurotoxins of types A, B, E, and F are produced by a diverse group of anaerobic spore-forming bacteria, including Clostridium botulinum groups I and II, Clostridium butyricum, and Clostridium baratii. The routine laboratory diagnostics of botulism is based on the detection of botulinum neurotoxin in the patient. Detection of toxin-producing clostridia in the patient and/or the vehicle confirms the diagnosis. The neurotoxin detection is based on the mouse lethality assay. Sensitive and rapid in vitro assays have been developed, but they have not yet been appropriately validated on clinical and food matrices. Culture methods for C. botulinum are poorly developed, and efficient isolation and identification tools are lacking. Molecular techniques targeted to the neurotoxin genes are ideal for the detection and identification of C. botulinum, but they do not detect biologically active neurotoxin and should not be used alone. Apart from rapid diagnosis, the laboratory diagnostics of botulism should aim at increasing our understanding of the epidemiology and prevention of the disease. Therefore, the toxin-producing organisms should be routinely isolated from the patient and the vehicle. The physiological group and genetic traits of the isolates should be determined.
  • Lokki, A I; Järvelä, Irma; Israelsson, Elisabeth; Maiga, Bakary; Troye-Blomberg, Marita; Dolo, Amagana; Doumbo, Ogobara K; Meri, Seppo; Holmberg, Ville (BioMed Central Ltd, 2011)
    Abstract Background Fulani are a widely spread African ethnic group characterized by lower susceptibility to Plasmodium falciparum, clinical malaria morbidity and higher rate of lactase persistence compared to sympatric tribes. Lactase non-persistence, often called lactose intolerance, is the normal condition where lactase activity in the intestinal wall declines after weaning. Lactase persistence, common in Europe, and in certain African people with traditions of raising cattle, is caused by polymorphisms in the enhancer region approximately 14 kb upstream of the lactase gene. Methods To evaluate the relationship between malaria and lactase persistence genotypes, a 400 bp region surrounding the main European C/T-13910 polymorphism upstream of the lactase gene was sequenced. DNA samples used in the study originated from 162 Fulani and 79 Dogon individuals from Mali. Results Among 79 Dogon only one heterozygote of the lactase enhancer polymorphism was detected, whereas all others were homozygous for the ancestral C allele. Among the Fulani, the main European polymorphism at locus C/T-13910 was by far the most common polymorphism, with an allele frequency of 37%. Three other single-nucleotide polymorphisms were found with allele frequencies of 3.7%, 1.9% and 0.6% each. The novel DNA polymorphism T/C-13906 was seen in six heterozygous Fulani. Among the Fulani with lactase non-persistence CC genotypes at the C/T-13910 locus, 24% had malaria parasites detectable by microscopy compared to 18% for lactase persistent genotypes (P = 0.29). Pooling the lactase enhancer polymorphisms to a common presumptive genotype gave 28% microscopy positives for non-persistent and 17% for others (P = 0.11). Conclusions Plasmodium falciparum parasitaemia in asymptomatic Fulani is more common in individuals with lactase non-persistence genotypes, but this difference is not statistically significant. The potential immunoprotective properties of dietary cow milk as a reason for the partial malaria resistance of Fulani warrant further investigation.
  • Lyhs, Ulrike; Korkeala, Hannu; Vandamme, Peter; Björkroth, Johanna (Elsevier, 2001)
    Spoilage characterised by bulging of lids and gas formation affected various product lots of different marinated herring types. Microbiological analyses resulted in growth on MRS and Rogosa SL agar. Altogether, 206 randomly selected colonies from two unspoiled and ten spoiled samples were characterised using phenotypical key tests and a 16123S rRNA gene-based RFLP identification database. L. alimentarius was found to be the specific spoilage organism in all samples. All isolates obtained from the different product types were of the same clonal type. The slight rise in pH value together with marked gas production suggested a rare lactic acid bacteria spoilage type called ‘protein swell’. L. alimentarius has not been previously associated with herring spoilage.
  • Koort, Joanna; Vandamme, Peter; Schillinger, Ulrich; Holzapfel, Wilhelm; Björkroth, Johanna (Society for General Microbiology, 2004)
    On the basis of phenotypic and DNA-DNA reassociation studies, strain CCUG 34545T has been considered to represent a distinct Lactobacillus curvatus subspecies, Lactobacillus curvatus subsp. melibiosus. However, in several independent studies dealing with Lactobacillus sakei and L. curvatus strains, the subspecies division of L. curvatus has been found to be controversial. The original study distinguishing the two subspecies within both L. curvatus and L. sakei also lacked 16S rRNA gene sequence analyses. Therefore, the taxonomic position of L. curvatus subsp. melibiosus CCUG 34545T was re-evaluated in a polyphasic taxonomy study that included 16S rRNA gene sequence analysis, DNA-DNA reassociation, DNA G+C content deternmination, numerical analysis of ribotypes and whole-cell protein patterns and the examination of some fundamental phenotypic properties. The results obtained indicate that strain CCUG 34545T and its duplicate, CCUG 41580T, are Lactobacillus sakei subsp. carnosus strains and that L. curvatus subsp. melibiosus is a later synonym of L. sakei subsp. carnosus.
  • Björkroth, Johanna; Korkeala, Hannu (International Association for Food Protection, 1997)
    Spoilage characterized by bulging as a result of gas formation in bottled ketchup was studied and resulted in growth on MRS and Rogosa selective Lactobacillus agar. Seventy randomly selected isolates were typed using restriction endonuclease analysis (ClaI, EcoRI, HindIII) and were found to have identical patterns. The strain was identified as Lactobacillus fructivorans using morphological, physiological and biochemical characteristics, combined with information obtained from rRNA gene restriction patterns. Factors affecting growth and survival of this L. fructivorans strain in production circumstances were also studied. Lactobacillus count of 105 CFU/g resulted in spoilage of inoculated ketchup samples. Spoilage occurred only in samples incubated at 15 to 30°C. L. fructivorans implicated in causing spoilage demonstrated heat resistance with a D-value of 1.2 min at 65°C. The strain did not show resistance against alkaline, active chloride containing detergent sanitizer, and also alkyldimethylbenzyl ammonium chloride and alkyldimethylethylbenzyl ammonium chloride containing sanitizer was found to be effective against it.
  • Koort, Joanna; Murros, Anna; Coenye, Tom; Eerola, Susanna; Vandamme, Peter; Sukura, Antti; Björkroth, Johanna (American Society for Microbiology (ASM), 2005)
    Unidentified lactic acid bacterium (LAB) isolates which had mainly been detected in spoiled, marinated, modified atmosphere packaged (MAP) broiler meat products during two previous studies were identified and analyzed for their phenotypic properties and the capability to produce biogenic amines. To establish the taxonomic position of these isolates, 16S rRNA gene sequence analysis, numerical analysis of ribopatterns, and DNA-DNA hybridization experiments were done. Unexpectedly for a meat spoilage associated LAB, the strains utilized glucose very weakly. According to the API 50 CHL test, arabinose and xylose were the only carbohydrates strongly fermented. None of the six strains tested for production of histamine, tyramine, tryptamine, phenylethylamine, putrescine and cadaverine were able to produce these main meat-associated biogenic amines in vitro. Polyphasic taxonomy approach showed that these strains represent a new Lactobacillus species. The six isolates sequenced for the 16S rRNA encoding genes shared the highest similarity (95.0 to 96.3%) with the sequence of the Lactobacillus durianis type strain. In the phylogenetic tree, these isolates formed a distinct cluster within the Lactobacillus reuteri -group which also includes L. durianis. Numerical analyses of HindIII/EcoRI ribotypes placed all isolates together in a cluster with seven subclusters well-separated from the L. reuteri group reference strains. The DNA-DNA hybridization levels between Lactobacillus sp. nov. isolates varied from 67 to 96% and low hybridization levels (3-15%) were obtained with the L. durianis type strain confirming that these isolates belong to same species different from L. durianis. The name Lactobacillus oligofermentans sp. nov. is proposed, with strain LMG 22743T (=DSM 15707T =AMKR18 T) as the type strain.
  • Snellman, Hanna (Oulun Historiaseura, 2008)
    Aloittaessani tutkimushankkeen "Göteborg - Sallan suurin kylä" vuonna 2000 olin astumassa maailmaan, joka oli minulle vieras.' Saadakseni esiymmärrystä tutkimuskohteestani, ruotsinsuomalaisista, aloin seurata Ruotsissa ilmestyvää suomenkielistä sanomalehteä Viikkoviestiä. Luin niin artikkeleita, mainoksia kuin ilmoituksiakin. Lehteä säännöllisesti lukiessani kiinnitin melko pian huomiota siihen, että sana Lappi esiintyi lehden henkilökohtaista- palstalla kumppaninhakuilmoituksissa useammin kuin mikään muu alue Suomessa. Karjala tuli hyvänä kakkosena. Vuosien varrella lehden nimi muuttui Ruotsin Sanomiksi. Alun lyhyen tauon jälkeen lehden välityksellä oli edelleen kerran viikossa mahdollisuus hakea ystävää. Kun Ruotsin Sanomat -lehden ilmestyminen päättyi, päättyi myös aineistonkeruuni. Vuosina 2000-2005 poimin systemaattisesti lehden henkilökohtaista-palstalta kaikki ne ilmoitukset, joissa mainitaan tavalla tai toisella Matillekin niin rakas Pohjois-Suomi. Näitä ilmoituksia on yhteensä 23 kappaletta, joista 13:ssa mies etsii naista ja kymmenessä nainen miestä. Tässä artikkelissa esittelen ilmoitusten tyypillisiä piirteitä ja pohdin sitä, miksi juuri Lappi kaikista Suomen maakunnista esiintyy ilmoituksissa niin usein.
  • Lignell, Antti; Khriachtchev, Leonid; Pettersson, Mika; Räsänen, Markku (American Institute of Physics, 2002)
  • Hanski, I; Meyke, E (2005)
    The Glanville fritillary (Melitaea cinxia) has been studied in Finland within an area of 50 by 70 km since 1993. We analyse 11-yr time series for aggregate populations in 20 squares of 4 by 4 km. Different aggregate populations exhibit dissimilar long-term trends, including significant increasing and decreasing trends as well as stable population sizes, and their average size is significantly related to the amount of habitat but not of host plants. Precipitation shows spatially correlated variation in the study area, recorded with high-resolution weather radar. Spatial variation in August and June precipitation explains a significant amount of spatial variation in the dynamics of aggregate populations. Many processes operating in local populations have strong effects, but these effects are not consistent in time and space and they often counter each other, making it less likely that one would detect a signal of local processes in large-scale data for aggregate populations.
  • Torsti, Pilvi (Nuorisotutkimusverkosto/Nuorisotutkimusseura, 2009)
    Nykytilanne ruuhkavuosia elävien perheiden arjessa: Kaikki kouluikäiset ovat mukana perusopetuksessa eli käyvät koulua. Valtaosa nuoremmista lapsista osallistuu julkisesti järjestettyyn varhaiskasvatukseen eli käy päivähoidossa. Aikuiset käyvät töissä. Tutkimukset kertovat, kuinka perheitä vaivaavat kiire ja ajan puute. Olisiko aika harkita rakennemuutosta lasten ja nuorten sekä myös aikuisten ajankäyttöön yhteiskunnassamme?
  • Lodenius, M.; Seppänen, A.; Autio, S. (Pergamon Journals Ltd., 1987)
  • Kuusi, T.; Laaksovirta, K.; Liukkonen-Lilja, H.; Lodenius, M.; Piepponen, S. (J. F. Bergmann Verlag, 1981)
  • Lodenius, M.; Kuusi, T.; Laaksovirta, K.; Liukkonen-Lilja, H.; Piepponen, S. (Finnish Zoological and Botanical Publishing Board, 1981)
  • Koivula, M.; Punttila, P.; Haila, Y.; Niemelä, J. (Blackwell, 1999)
  • Krekola, Joni (University of Helsinki Department of Social Science History, 2008)
    The legacy of Lenin in Finland, especially since the late Cold War era of the 1960s, is the subject of this article. Lenin’s grip on Finland is explained by his personal contribution to the history of Finland, an issue that has been debated since the gaining of independence in 1917. After the first demonizing decades and the Second World War, Lenin’s public representations became more positive in Finland. A museum was dedicated to him in 1946, and later Lenin started to appear in names and statues that still exist in Finland. In this respect, but to a far lesser extent,Finland resembles the Eastern European countries that became People’s Democracies.
  • Tanislav, Christian; Grittner, Ulrike; Misselwitz, Bjoern; Jungehuelsing, Gerhard Jan; Enzinger, Christian; von Sarnowski, Bettina; Putaala, Jukka; Kaps, Manfred; Kropp, Peter; Rolfs, Arndt; Tatlisumak, Turgut; Fazekas, Franz; Kolodny, Edwin; Norrving, Bo (BioMed Central Ltd, 2014)
    Abstract Background Translating knowledge derived from medical research into the clinical setting is dependent on the representativeness of included patients. Therefore we compared baseline data of patients included in a recent large study addressing young stroke in comparison to a large representative stroke registry. Methods We analysed baseline data of 5023 patients (age 18-55 years) with an acute cerebrovascular event included in the sifap1 (Stroke in Young Fabry Patients) study. For comparison 17007 stroke patients (age 18-55 years) documented (2004-2010) in a statutory stroke registry of the Institute of Quality Assurance Hesse of the Federal State of Hesse (GQH), Germany. Results Among 17007 juvenile (18-55 years) patients identified in the GQH registry 15997 had an ischaemic stroke or TIA (91%) or an intracranial haemorrhage (9%). In sifap1 5023 subjects were included. Sex distribution was comparable (men: 59% sifap1 versus 60.5% GQH) whereas age differed between the groups: median age was 46 years in sifap1 versus 49 years in GQH. Slightly higher percentages for diabetes mellitus and hypertension in the GQH registry were noted. There were no differences in stroke severity as assessed by NIHSS (median 3) and mRS (median 2). In patients with ischaemic stroke or TIA (n = 4467 sifap1; n = 14522 GQH) higher rates of strokes due to small artery occlusion and atherosclerosis occurred in older age groups; cardioembolism and strokes of other determined cause occurred more frequently in younger patients. Conclusions The comparison of baseline characteristics between the sifap1 study and the GQH registry revealed differences mainly determined by age.
  • Kauppi, P.E. (Economist Newspaper Ltd., 2009)
    SIR – In looking for cost-efficient CCS, please step up and walk to your window, where you may see a tree. The evolution of woody plants has solved the problem of capture (photosynthesis) and storage (formation of durable cells) at minimal cost. After what is called “forest transition”, woody resources of a country cease to shrink and start to expand. Forest transition implies a shift of the landscape from a carbon source to a carbon sink, thus marking the onset of organic, cheap CCS. Alexander Mather of the University of Aberdeen predicted in 1992 that forest transition is the likely future of tropical countries, too. Since then, however, biofuel clearings and other pressures have created new concerns. Organic CCS will again become an issue as climate negotiators reconvene to consider a post-Kyoto treaty in Copenhagen in December this year. Pekka Kauppi Professor of environmental science and policy University of Helsinki Helsinki
  • Susiluoto, Tuija; Korkeala, Hannu; Björkroth, Johanna (Elsevier, 2002)
    Lactic acid bacteria (LAB) in retail, modified-atmosphere-packaged (MAP), marinated broiler meat strips on sell-by day were mainly identified as Leuconostoc gasicomitatum. A total of 32 packages, 3 to 5 packages of 7 differently marinated broiler meat products, were studied at the end of the producer-defined shelf life (at 6ºC, 7 to 9 days depending on the manufacturer). Prior to the microbiological analyses, appearance and smell of the product was checked and pH measured. Bacteria were cultured on MRS and Tomato Juice Agar (TJA), Rogosa SL agar (SLA), Plate Count Agar (PCA) and Streptomycin Thallium Acetate Agar (STAA) for the enumeration of LAB, lactobacilli, total bacterial count and B. thermosphacta, respectively. The average CFU/g of the 32 packages was 2.3 × 108 on PCA. The highest bacterial average, 3.1 × 108, was recovered on TJA, the corresponding CFU/g averages on MRS and SLA being 2.3 × 108 and 1.3 × 108, respectively. Despite the high LAB numbers, radical spoilage changes such as unpleasant odor, slime production and formation of gas were not recognized. B. thermosphacta did not form a significant part of the bacterial population since none of the levels exceeded the spoilage threshold level of 105 CFU/g reported in previous studies. In order to characterize the dominating LAB population, as many as 85, 85 and 88 colonies from MRS, TJA and SLA, respectively, were randomly picked and cultured pure. LAB were identified to species level using a 16 and 23S rDNA HindIII RFLP (ribotyping) database. Fifty-six of the 170 isolates picked from the non-selective LAB media (MRS and TJA) were identified as Leuconostoc gasicomitatum, followed by Carnobacterium divergens (41 isolates), Lactobacillus sakei and Lactobacillus curvatus subsp. melibiosus (31 isolates) and Lactobacillus curvatus subsp. curvatus (20 isolates) species. SLA proved not to be completely selective for lactobacilli because the growth of Leuconostoc spp. was not inhibited, Carnobacterium spp. were the only species not detected on SLA.
  • Lyhs, Ulrike; Koort, Joanna M.K.; Lundström, Hanna-Saara; Björkroth, K. Johanna (Elsevier, 2003)
    Spoilage characterised by strong slime and gas formation affected some manufacture lots of 2 an acetic-acid Baltic herring (Culpea haerengus membras) preserve after few weeks’ storage 3 at 0-6°C. The product consisted of herring filets in acetic acid marinade containing sugar, 4 salt, allspice and carrot slices. Microbiological analyses of the spoiled product showed high 5 lactic acid bacterium (LAB) levels ranging from 4.5 ×108 to 2.4 × 109 CFU/g. Yeasts were 6 not detected in any of the herring samples. Since LAB contaminants seldom are associated 7 with fresh fish, LAB populations associated with marinade ingredients (carrots, allspice) 8 were also analysed. The highest LAB levels exceeding 107 CFU/g were detected in 9 equilibrium modified atmosphere packaged baby carrots whereas the levels detected in the 10 allspice samples did nor exceed 4.3 × 105. A total of 176 randomly selected LAB isolates 11 originating from herring, carrot and allspice samples were further identified to species level 12 using a 16 and 23S rRNA gene RFLP (ribotyping) database. Leuconostoc gelidum and 13 Leuconostoc gasicomitatum strains dominated both in the spoiled herring and carrot samples. 14 These species are heterofermentative producing CO2 from glucose and they also produce 15 dextran from sucrose. Inoculation of some commercial herring products with spoilage- 16 associated L. gelidum and L. gasicomitatum strains verified that these strains have the 17 capability of producing slime and gas in herring preserves although slime formation was not 18 as strong as in the original samples. Since L. gelidum and L. gasicomitatum strains were 19 commonly detected in carrots, carrot slices used for the fish marinade were considered to be 20 the probable source of these specific spoilage organisms. 21
  • Nymark, S.; Heikkinen, H.; Haldin, C.; Donner, K.; Koskelainen, A. (2005)
    Rod responses to brief pulses of light were recorded as electroretinogram (ERG) mass potentials across isolated, aspartate-superfused rat retinas at different temperatures and intensities of steady background light. The objective was to clarify to what extent differences in sensitivity, response kineticsandlight adaptationbetweenmammalianandamphibianrods can be explained by temperature and outer-segment size without assuming functional differences in the phototransduction molecules. Corresponding information for amphibian rods from the literature was supplemented by new recordings from toad retina. All light intensities were expressed as photoisomerizations per rod (Rh∗). In the rat retina, an estimated34%of incident photons at the wavelength of peak sensitivity caused isomerizations in rods, as the (hexagonally packed) outer segments measured 1.7 μm×22 μm and had specific absorbance of 0.016 μm−1 on average. Fractional sensitivity (S) in darkness increased with cooling in a similar manner in rat and toad rods, but the rat function as a whole was displaced to a ca 0.7 log unit higher sensitivity level. This difference can be fully explained by the smaller dimensions of rat rod outer segments, since the same rate of phosphodiesterase (PDE) activation by activated rhodopsin will produce a faster drop in cGMP concentration, hence a larger response in rat than in toad. In the range 15–25◦C, the waveformand absolute time scale of dark-adapted dim-flash photoresponses at any given temperature were similar in rat and toad, although the overall temperature dependence of the time to peak (tp) was somewhat steeper in rat (Q10 ≈ 4 versus 2–3). Light adaptation was similar in rat and amphibian rods when measured at the same temperature. The mean background intensity that depressed S by 1 log unit at 12◦C was in the range 20–50 Rh∗ s−1 in both, compared with ca 4500 Rh∗ s−1 in rat rods at 36◦C. We conclude that it is not necessary to assume major differences in the functional properties of the phototransduction molecules to account for the differences in response properties of mammalian and amphibian rods.