Glycoprofiling of bifidobacterial consumption of human milk oligosaccharides demonstrates strain specific, preferential consumption of small chain glycans secreted in early human lactation

The molecular basis by which human breast milk supports the development of a protective intestinal microbiome in infants is unknown. After lactose and lipids, human milk oligosaccharides (HMOs) are quantitatively the third largest and most diverse component of breast milk. In this work, glycomic profiling of HMO consumption by bifidobacteria using Fourier transform ion cyclotron resonance mass spectrometry reveals that one species, Bifidobacterium longum biovar infantis ATCC 15697, an isolate from the infant gut, preferentially consumes small mass oligosaccharides, representing 63.9% of the total HMOs available. These HMOs were detected in human breast milk at the onset and constantly through the first month of lactation by use of high performance liquid chromatography-chip time-of-flight mass spectrometry. Further characterization revealed that strain ATCC 15697 possesses both fucosidase and sialidase activities not present in the other tested strains. This work provides evidence that these small mass HMOs are selectively metabolized by select bifidobacterial strains and represent a potential new class of bioactive molecules functioning as prebiotics to facilitate a protective gut colonization in breast-fed newborns.     

Messung des Erpositionsklimas IX. (Schluszteil)

Ohne Zusammenfassung     

Genetische Ressourcen der Kulturpflanzen im alpinen Raum

Zusammenfassung Die Kulturpflanzenevolution im alpinen Raum ist durch drei Faktoren geprägt, durch klimatische, geologisch-landschaftsmorphologische und geschichtliche. Die Aufgliederung in cine Vielzahl von ökologischen Nischen, in denen verdrängte Arten und Varietäten überleben konnten, mußte zwangsläufig zu einer bestimmten Formenanreicherung führen. Ihr stcht aber ein scharfer natürlicher Selektionsdruck einschränkend entgegen, der mit fortschreitender Höhenlage stärker wird. Er bestimmt letztlich das Ausschen der Populationen und läßt allfällige Zufallsfaktoren bei beginnender Einnischung und kleiner werdenden Populationsgrößen in den Hintergrund treten. Darin liegt die Ursache, daß mit zunehmender Höhenlage die Populationen uniformer werden, die umgekehrt im Flachland die größte Variabilität aufweisen.Die Kulturpflanzenarten, Varietäten und Sorten sind einem ständigen Bewegungsprozeß unterworfen, bedingt durch das Streben des Menschen, Leistung, Qualität, Aussehen, usw., zu verbessern. Die Suche nach Neuem birgt stets die Möglichkeit in sich, daß ein besseres Sortiment das altbewährte verdrängt. Ist eine Sorte ausreichend adaptierfähig und bringt sie eine Verbesserung mit sich, wird sie sich schrittweise — das alte Sortiment vor sich herschiebend — bis in die Alpentäler ausbreiten. Die Frage, wieviele Arten und Varietäten auf diese Weise ins Land gelangten, bleibt unbeantwortet. Jedenfalls waren es nur wenige, die diesem Verdrängungsprozeß haben standhalten können und bis heute erhalten geblieben sind.Wenn wir im Rückzugsgebiet der Alpen eine Formenanhäufung finden, die historisch betrachtet einen Abriß des Widerstandsfähigsten aus den letzten Jahrhunderten darstellt, ist dieser Formenreichtum doch bescheiden im Vergleich zu dem eines Genzentrums. Besteht hier das entscheidende evolutionsmotorische Moment darin, daß neu entstandene Formen auch eine entsprechende Überlebens-und Fortpflanzungschance besitzen, wirkt der scharfe Selektionsdruck der Alpen einer solchen Mannigfaltigkeit entgegen und wird stets in genotypische wie phänotypische Uniformität münden.

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Crop genetic ressources in the alps

Summary The evolution of cultivated plants in the area of the Alps is especially influenced by climatical, geological-orographical and historical factors. The available abundance of ecological niches providing chances for the survival of otherwise displaced species and varieties, consequently led to a certain increase of diversity. It is counteracted by strong natural selection pressures increasing with progressive altitudes. These selection pressures ultimately determine the composition of the populations and predominate over coincidental factors during the first phases of annidation connected with descreasing population size. That causes an increasing uniformity of the populations in higher altitudes whereas in the lowlands the highest diversity can be found.Due to human efforts in improving yields, quality, appearance, etc., of cultivated species, varieties and cultivars, they are subject to a permanent evolutionary process. The search for new material always includes the possibility that better accessions displace the well-known old ones. If a variety is sufficiently adaptable and shows improved characters, it will proceed step by step, — pushing the old accessions ahead of it — into the valleys of the Alps. How many species and varieties were introduced in this way is a question which cannot be answered. Anyway, only a few varieties could resist this displacing process and are in existance still today.Though we can find a certain amount of variation in the refugial area of the Alps, which, as seen from the historical standpoint of view, represents a part of the most resistant races from the last few centuries, this variation is relatively low in comparison with that of a gene center. In a gene center the decisive evolutionary mechanisms result in the maintaining of newly evolved forms whereas the strong selection pressures of the Alps counteract a high variability and will always lead to genotypical and phenotypical uniformity.

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Semisynthesis and pharmacological investigation of lipo-alkaloids prepared from aconitine

Processed aconite drugs are widely used in Eastern medicine as painkillers and antirheumatic agents. It is known that the traditional processing of aconite drugs increases the amount of lipo-alkaloids. In order to obtain information about the pharmacological potential of these compounds, semisynthesis of 9 aconitine-derived lipo-alkaloids was carried out and their COX-1, COX-2 and LTB₄ formation inhibitory activities were investigated. It was found that compounds esterified with unsaturated fatty acids demonstrated significant COX-2 inhibitory effects, while in the COX-1 assay only 14-benzoylaconine-8-O-eicosapentaenoate exerted remarkable activity. The inhibition of LTB₄ formation was pronounced in cases of long chain fatty acid derivatives.     

Organochlorine and Metal Accumulation in Fish (Phoxinus phoxinus) Along a North-South Transect in the Alps

Southern populations of the European minnow fromremote oligotrophic mountain lakes along an Alpinenorth-south transect accumulated more p,p DDE andPCBs than northern populations. As these semi-volatileorganochlorines predominantly evaporate in warmcountries, higher rates of condensation (deposition)are assumed to occur in the southern slopes of theAlps. The higher accumulation of lead and cadmium insouthern population is rather attributed to geogenicand specific environmental impacts than to atmosphericdeposition. Increasing liver ratios of [glutathionedisulfide]/[glutathione], a potential indicator foroxidative stress, from north to south reflect thegenerally higher toxic load at remote sites at thesouthern edge of the Alps. However, histopathologicalchanges in the liver did not correlate withaccumulated toxicants indicating that deposition doesnot lead to severe lesions but induces specificmechanisms for detoxification.     

Induction of tumors in mice by genomic hypomethylation

Genome-wide DNA hypomethylation occurs in many human cancers, but whether this epigenetic change is a cause or consequence of tumorigenesis has been unclear. To explore this phenomenon, we generated mice carrying a hypomorphic DNA methyltransferase 1 (Dnmt1) allele, which reduces Dnmt1 expression to 10% of wild-type levels and results in substantial genome-wide hypomethylation in all tissues. The mutant mice were runted at birth, and at 4 to 8 months of age they developed aggressive T cell lymphomas that displayed a high frequency of chromosome 15 trisomy. These results indicate that DNA hypomethylation plays a causal role in tumor formation, possibly by promoting chromosomal instability.     

Quantitative und qualitative Veränderungen im A-Horizont von Sandböden nach Umwandlung von Dauergrünland in Ackerland

Quantitative and qualitative changes in soil properties of A- horizons of sandy soils caused by conversion of grassland to arable land Changes in physical soil properties and in soil organic matter of the A-horizons due to the conversion of permanent grassland to arable land are quantified and described as a function of time for sandy soils. The study was carried out in an area northeast of Hannover. A decrease of about 100 t/ha C_org (- 57%), 5 – 6 t/ha N_org (- 58%) and 1 t/ha S_t (- 58%) was measured for a period of 2 – 4 years after grassland conversion. Thereby the quality of the soil organic matter remains unchanged (no changes of the C/N ratio and of the distribution of N_org in 5 N-fractions). However, an increase of soil bulk density from 1.0 to 1.3 g/cm³ and a decrease of total pore volume from 0.59 to 0.47 were observed. The fast mineralization of soil organic matter in the A-horizon following the conversion of grassland soils results in a temporary heavily increased nitrate input into the groundwater. Furthermore mineralization and leaching of nitrate and sulfate induces an acidification push in the soil by a proton release in the order of 350 keq/ha during a 2 – 4 years period. However, this proton production is compensated quantitatively by several applications of lime or marl by farmers and by the buffering of bases cations released from mineralized soil organic matter.