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1Latest Papers from Table of Contents or Articles in PressS. C. Mack ; H. Witt ; R. M. Piro ; L. Gu ; S. Zuyderduyn ; A. M. Stutz ; X. Wang ; M. Gallo ; L. Garzia ; K. Zayne ; X. Zhang ; V. Ramaswamy ; N. Jager ; D. T. Jones ; M. Sill ; T. J. Pugh ; M. Ryzhova ; K. M. Wani ; D. J. Shih ; R. Head ; M. Remke ; S. D. Bailey ; T. Zichner ; C. C. Faria ; M. Barszczyk ; S. Stark ; H. Seker-Cin ; S. Hutter ; P. Johann ; S. Bender ; V. Hovestadt ; T. Tzaridis ; A. M. Dubuc ; P. A. Northcott ; J. Peacock ; K. C. Bertrand ; S. Agnihotri ; F. M. Cavalli ; I. Clarke ; K. Nethery-Brokx ; C. L. Creasy ; S. K. Verma ; J. Koster ; X. Wu ; Y. Yao ; T. Milde ; P. Sin-Chan ; J. Zuccaro ; L. Lau ; S. Pereira ; P. Castelo-Branco ; M. Hirst ; M. A. Marra ; S. S. Roberts ; D. Fults ; L. Massimi ; Y. J. Cho ; T. Van Meter ; W. Grajkowska ; B. Lach ; A. E. Kulozik ; A. von Deimling ; O. Witt ; S. W. Scherer ; X. Fan ; K. M. Muraszko ; M. Kool ; S. L. Pomeroy ; N. Gupta ; J. Phillips ; A. Huang ; U. Tabori ; C. Hawkins ; D. Malkin ; P. N. Kongkham ; W. A. Weiss ; N. Jabado ; J. T. Rutka ; E. Bouffet ; J. O. Korbel ; M. Lupien ; K. D. Aldape ; G. D. Bader ; R. Eils ; P. Lichter ; P. B. Dirks ; S. M. Pfister ; A. Korshunov ; M. D. Taylor
Nature Publishing Group (NPG)
Published 2014Staff ViewPublication Date: 2014-02-21Publisher: Nature Publishing Group (NPG)Print ISSN: 0028-0836Electronic ISSN: 1476-4687Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsKeywords: Animals ; Brain Neoplasms/drug therapy/genetics ; CpG Islands/*genetics ; DNA Methylation/drug effects ; Embryonic Stem Cells/metabolism ; Ependymoma/drug therapy/*genetics ; Epigenesis, Genetic/*genetics ; Epigenomics ; Female ; Gene Expression Regulation, Neoplastic ; Gene Silencing/drug effects ; Histones/drug effects/metabolism ; Humans ; Infant ; Mice ; Mice, Inbred NOD ; Mice, SCID ; Mutation/genetics ; Phenotype ; Polycomb Repressive Complex 2/metabolism ; Prognosis ; Rhombencephalon/pathology ; Xenograft Model Antitumor AssaysPublished by: -
2Articles: DFG German National LicensesStaff View
ISSN: 0156-7446Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, NutritionEconomicsDescription / Table of Contents: Keynote addressesNotes: National Agricultural Outlook Conference: Canberra Theatre 27-29 January 1981URL: -
3Articles: DFG German National LicensesStaff View
ISSN: 1365-2427Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: BiologyNotes: 1. A number of planktonic cyanobacteria species form resting stages that survive in the sediments of lakes. The significance of this life history strategy to the ecology of new planktonic populations was investigated in Esthwaite Water, a mesotrophic lake in the English Lake District.2. A simple trapping technique was used to quantify vertical movements of five species of buoyant gas-vacuolate cyanobacteria from close to the sediments, along a depth transect.3. ‘Recruitment’ from the sediments was found to be widespread amongst the cyanobacteria species associated with the summer phytoplankton community.4. Estimates of the vertical upward fluxes of cyanobacteria based upon trap catches could not account for observed increases in the planktonic populations suggesting that ‘recruitment’ was not a significant source of biomass.5. Vertical upward movements of Anabaena solitaria were recorded prior to this species becoming established in the plankton suggesting that benthic populations might be a source of cells for initial pelagic growth of populations of this species.6. Low numbers of vegetative filaments of Anabaena flos-aquae, Aphanizomenon flos-aquae and Oscillatoria agardhii were observed in the plankton through the winter. These small overwintering populations appeared to be the primary source of inocula for the large summer populations of these species.Type of Medium: Electronic ResourceURL: -
4Articles: DFG German National LicensesJeffreson, S. ; Rush, R. ; Zettler, C. ; Frewin, D. B. ; Head, R. J.
Oxford, UK : Blackwell Publishing Ltd
Published 1995Staff ViewISSN: 1440-1681Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineNotes: 1. The levels of the neurotrophic factor, nerve growth factor (NGF) in the mesenteric vascular bed of the spontaneously hypertensive rat (SHR) were greater than those in the corresponding vascular bed of normotensive Wistar-Kyoto rats (WKY).2. Administration of angiotensin II (200 ng/kg per min, by minipump) for 2 weeks to juvenile WKY rats increased the levels of NGF in the mesenteric vasculature to those seen in untreated SHR.3. Administration of the angiotensin II receptor antagonists losartan (30 mg/kg per day, p.o.) or PD144277 (10 mg/kg per day, p.o.) to juvenile SHR for 4 weeks reduced the levels of NGF such that they were indistinguishable from the values obtained for normotensive WKY rats.4. The results confirm the elevated level of NGF in the mesenteric vasculature of the SHR and suggest that angiotensin II may play a role in regulating the abnormal concentrations of the protein in this tissue.Type of Medium: Electronic ResourceURL: -
5Articles: DFG German National LicensesDyer, S. M. ; Bexis, S. ; Mano, M. T. ; Lande, I. S. ; Frewin, D. B. ; Head, R. J.
Oxford, UK : Blackwell Publishing Ltd
Published 1994Staff ViewISSN: 1440-1681Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineNotes: 1. The effects of 5-hydroxytryptamine (5-HT) in the absence and presence of noradrenaline (NA) or the thromboxane-A2 mimetic, U44069, were investigated in ring preparations of marmoset aorta.2. 5-HT (0.001-10 μmol/L) produced little or no contractile response in preparations at basal tone. When the tone was elevated to 50% of maximum with NA the predominant response to 5-HT was relaxation. The 5-HT2 receptor antagonist LY53857 (0.1 μmol/L) unmasked a contractile response to low concentrations of 5-HT (0.01 - 1.0 μmol/L) and reduced relaxation to high concentrations of 5-HT (1.0-10 μmol/L) in vessels precontracted with NA.3. In U44069-contracted vessels, 5-HT was contractile in the range 0.01-1 μmol/L and relaxant in concentrations of 6.0-10.0 μmol/L. Ketanserin (1.0 μmol/L) had no effect on the contraction or relaxation to 5-HT.4. The relaxant response to 5-HT was not significantly diminished in endothelium-impaired arteries.5. In conclusion, 5-HT exerts complex inhibitory and excitatory actions on the marmoset aorta. The inhibitory actions are not endothelium-dependent and the excitatory actions do not appear to involve the 5-HT2 receptor.Type of Medium: Electronic ResourceURL: -
6Articles: DFG German National LicensesStaff View
ISSN: 1440-1681Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineNotes: 1. Blood pressure (BP) declines dramatically in the final week of gestation in the pregnant spontaneously hypertensive rat (SHR). This study investigated the hypothesis that alterations of vascular neuroeffector function in the pregnant SHR and normotensive Wistar-Kyoto (WKY) rat are responsible for this decline.2. Pregnancy in SHR and WKY rats was associated with a significant drop in BP in the last week of gestation.3. Responses of the perfused mesenteric vasculature to bolus doses of noradrenaline (NA) and potassium chloride (KC1) were decreased in preparations from SHR rats 4 days before delivery. This decreased responsiveness was absent in preparations from SHR rats 1 day before delivery. Responses of the perfused mesenteric vasculature to sympathetic nerve stimulation were not influenced by pregnancy in the SHR.4. It is concluded that while there are dynamic changes occurring in neurovascular function just prior to delivery, it is unlikely that they are wholly responsible for the dramatic decline in blood pressure in the SHR rat.Type of Medium: Electronic ResourceURL: -
7Articles: DFG German National LicensesStaff View
ISSN: 1476-4687Source: Nature Archives 1869 - 2009Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsNotes: [Auszug] To use ship time as efficiently as possible, both surface and subsurface measurements of temperature, salinity and chlorophyll a were recorded continuously while steaming2"3. Surface water was sampled through the ship's hull from a depth of 2 m, and sub- to surface water was pumped up ( 100 1 min ...Type of Medium: Electronic ResourceURL: -
8Articles: DFG German National LicensesStaff View
ISSN: 1476-4687Source: Nature Archives 1869 - 2009Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsNotes: [Auszug] HETEROGENEOUS ice nucleation in the atmosphere depends on the presence of solid particles which are derived either from outer space1 or result from events at the Earth's surface. It has been known for more than a century that certain meteorites (carbonaceous chondrites) contain organic matter, and ...Type of Medium: Electronic ResourceURL: -
9Articles: DFG German National LicensesStaff View
ISSN: 1476-4687Source: Nature Archives 1869 - 2009Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsNotes: [Auszug] A CONSIDERABLE number of organic compounds have now been shown to act as ice nuclei15, the most promising materials being those which can be sublimed without decomposition to form large numbers of particles active at temperatures near 0 C. The activities of a-phenazine, phloroglucinol dihydrate and ...Type of Medium: Electronic ResourceURL: -
10Articles: DFG German National LicensesStaff View
ISSN: 0029-554XSource: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: Energy, Environment Protection, Nuclear Power EngineeringPhysicsType of Medium: Electronic ResourceURL: -
11Articles: DFG German National LicensesStaff View
ISSN: 0006-291XSource: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyChemistry and PharmacologyPhysicsType of Medium: Electronic ResourceURL: -
12Articles: DFG German National LicensesStaff View
ISSN: 1432-1912Keywords: Catechol oestrogen ; Catecholamine ; Tyrosine hydroxylase ; Blood vessel ; Smooth muscleSource: Springer Online Journal Archives 1860-2000Topics: MedicineNotes: Summary 1. In the present study we have investigated the effects of oestrogens, catechol oestrogens, and catecholamines on tyrosine hydroxylase (TH) activity derived from rabbit mesenteric artery and vas deferens. 2. Both catechol oestrogens, 2-hydroxyoestradiol (2OHE2) and 2-hydroxyoesterone (2OHE1), inhibited TH activity in mesenteric artery and vas deferens in a concentration-dependent manner with potencies that were higher than those for noradrenaline but lower than that for dopamine. 3. When added to the reaction medium along with increasing concentrations of a pterin cofactor (200 to 1,500 μmol/l DMPH4), the catechol oestrogens (200 μmol/l) increased the apparent K m for DMPH4 without altering the maximum velocity (V max) of the reaction. Similar results were obtained with the addition of noradrenaline (200 μmol/l) and dopamine (120 μ/mol). Apparent K i values obtained for the catecholamines and catechol oestrogens were within the same order of magnitude and varied from 30 μmol/l for dopamine and 2OHE2 to 183 μmol/l for 2OHE1. 4. Oestradiol (E2) and 2-methoxyoestradiol (2MeOE2), i.e., oestrogens that do not possess a catechol moiety, exhibited only weak inhibitory effects on TH activity. At the highest concentration tested (1 mmol/l), they did not reduce enzyme activity below 58% of control values. Kinetic analysis revealed that these two oestrogens did not consistently affect either the V max of hydroxylation or the K m for DMPH4. 5. It is concluded that catechol oestrogens inhibit TH activity with a potency comparable to noradrenaline and dopamine. This inhibition is by competition with the pterin cofactor. Oestrogens that to not possess a catechol moiety are not effective inhibitors of TH. It is suggested that this property of the catechol oestrogens is most likely to be physiologically relevant only in tissues that either can synthesize them in situ from precursor oestrogens or can accumulate sufficient amounts of circulating catechol oestrogens such as may occur during pregnancy.Type of Medium: Electronic ResourceURL: -
13Articles: DFG German National LicensesStaff View
ISSN: 1432-1912Keywords: Oestrogens ; Catechol oestrogens ; O-methylated oestrogens ; Catecholamines ; Rabbit aorta ; Extraneuronal uptake ; O-Methylation ; DeaminationSource: Springer Online Journal Archives 1860-2000Topics: MedicineNotes: Summary 1. In the present study the influence of oestradiol, catechol oestrogens, and O-methylated oestrogens was determined on the contractile responses of the isolated rabbit aorta to (−)-adrenaline. 2. Oestradiol (40 μmol/l), 2-hydroxyoestradiol (2OHE2) (20 μmol/l), and 2-methoxyoestradiol (2MeOE2) (20 μmol/l) all sensitized the rabbit aorta to contractile responses to (−)-adrenaline. Similarly, the 2-hydroxy and 2-methoxy derivatives of oestrone and oestriol also sensitized the aorta to (−)-adrenaline-induced contractions. The largest degree of sensitization was seen in the presence of the 2-methoxysteroids. 3. Oestradiol and 2OHE2 did not increase responses of the aorta to (−)noradrenaline, while slight potentiation of contraction was seen in the presence of 2MeOE3. 4. The potentiating effect of 2OHE2 on contractile responses to (−)-adrenaline was abolished by prior treatment of the tissue with a COMT inhibitor (U-0521, 55 μmol/l). Conversely, pretreatment of the tissue with 2OHE2 prevented the augmented aortic contraction to (−)-adrenaline usually seen after inhibition of COMT. The non-additive nature of the sensitization seen after combined treatment with 2OHE2 and U-0521 was qualitatively similar to that seen following combined exposure to maximally effective concentrations of U-0521 and an inhibitor of extraneuronal uptake (hydrocortisone 100 μmol/l). 5. Oestradiol and 2MeOE2 reduced the formation of both the 3H-O-methylated, 3H-deaminated and the 3H-O-methylated deaminated metabolites of 3H-(−)-adrenaline (0.15 μmol/l) during exposure of the aorta to the tritiated catecholamine. Treatment of the aorta with the extraneuronal uptake inhibitor phenoxybenzamine (33 μmol/l) produced a similar inhibition of formation of all 3H-metabolites of 3H-(−)-adrenaline. 6. While preincubation with 2OHE2 markedly reduced the formation of 3H-O-methylated and 3H-O-methylated deaminated metabolites from 3H-(−)-adrenaline (0.15 μol/l), the formation of 3H-deaminated adrenaline metabolites was considerably enhanced by exposure to 2OHE2. Pretreatment of the aorta with the COMT inhibitor U-0521 produced a similar effect on 3H-adrenaline metabolism. 7. Oestradiol, 2OHE2, and 2MeOE2 did not alter the tritium contents retained in segments of aorta incubated with 3H (±)-isoprenaline (0.15 μol/l). In contrast, the three steroids reversed the enhanced retention of tritium in the aorta induced by prior inhibition of COMT (U-0521 55 μmol/l). 8. It is concluded that the biotransformation of oestradiol to its 2-hydroxy and 2-methoxy metabolites does not diminish the potentiating actions of the steroids on adrenaline-induced aortic contractions. Oestradiol and 2MeOE2 appear to produce their effects through inhibition of the extraneuronal amine uptake process, while 2OHE2, a substrate for COMT, probably exerts is sensitizing through a combination of inhibition of the extraneuronal uptake process and competitive inhibition of COMT.Type of Medium: Electronic ResourceURL: -
14Articles: DFG German National LicensesStaff View
ISSN: 1476-4687Source: Nature Archives 1869 - 2009Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsNotes: [Auszug] The crystalloluminescence observed during the nucleation of alkali halides is now well understood as an impurity phenomenon associated solely with three-dimensional, that is, homogeneous, nucleation1. Each pulse, several hundreds of photons in size, is emitted as the result of a single nucleation ...Type of Medium: Electronic ResourceURL: -
15Articles: DFG German National LicensesStaff View
ISSN: 1476-4687Source: Nature Archives 1869 - 2009Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsNotes: [Auszug] A consideration of the crystal structure1 of the oc-isomer of 1:3: 5-Ci/cZohexanetriol dihydrate (a-phloroglucitol dihydrate) led us to expect high nucleative power, which was confirmed by cloud chamber tests. Counts of up to 1011 nuclei/g were obtained at a temperature of -12 C, although owing to ...Type of Medium: Electronic ResourceURL: -
16Articles: DFG German National LicensesStaff View
ISSN: 1432-1912Keywords: Isoprenaline ; Extraneuronal uptake ; Catechol-O-methyltransferase ; Stereoselectivity ; Rabbit aortaSource: Springer Online Journal Archives 1860-2000Topics: MedicineNotes: Summary 1. This investigation examined the stereoselective nature of the steroid-sensitive extraneuronal O-methylation process for the isomers of isoprenaline in the rabbit aorta. 2. The rate of O-methylation of (-)- and (+)-isoprenaline was linear with substrate concentration in the range 0.24 to 4.7 μmol·l−1. There was marked preference for the O-methylation of (-)-isoprenaline rather than (+)-isoprenaline at low (〈0.94 μmol·l−1) substrate concentrations. In contrast, at concentrations equal to or greater than 9.4 μmol·l−1 the rates of O-methylation of (-)- and (+)-isoprenaline were similar. 3. Phenoxybenzamine (30 μmol·l−1) inhibited but did not abolish the O-methylation of both (-)- and (+)-isoprenaline when the isomers were present in a concentration range of 0.24 μmol·l−1 to 9.4 μmol·l−1. Phenoxybenzamine did not significantly influence the O-methylation of either (-)- or (+)-isoprenaline when the isomers were present at a concentration of 24 μmol·l−1. 4. Deoxycorticosterone acetate (DOCA) produced an equipotent and marked inhibition of the O-methylation of both (-)- and (+)-isoprenaline at a low (0.24 μmol·l−1) substrate concentration. When higher substrate concentrations were used, there was a significantly greater resistance to the inhibition of O-methylation of (-)-isoprenaline than was the case for (+)-isoprenaline. At a concentration of 9.4 μmol·l−1, the steroid failed to inhibit the O-methylation of (-)-isoprenaline but was effective in inhibiting the O-methylation of (+)-isoprenaline. 5. The selective inhibitory influence of DOCA on the O-methylation of (+)-isoprenaline was unaltered in cocainetreated tissues and in tissues incubated with propranolol. The latter observations suggest that neuronal uptake mechanisms and beta adrenoceptor mediated processes were not involved in the selective actions of DOCA upon the (+)-isomer of isoprenaline. 6. It is concluded that the phenoxybenzamine- and steroid-sensitive extraneuronal O-methylation of isoprenaline is stereoselective. Moreover the resistance of O-methylation to phenoxybenzamine and DOCA particularly at high substrate concentration is due to non-stereoselective diffusional entry of isoprenaline to a site or sites of O-methylation.Type of Medium: Electronic ResourceURL: -
17Articles: DFG German National LicensesStaff View
ISSN: 1432-1793Source: Springer Online Journal Archives 1860-2000Topics: BiologyNotes: Abstract Sediment-trap samples were collected during and after the occurrence of a salp (Salpa fusiformis) bloom in the Bay of Villefranche, Mediterranean Sea, in April/May 1985. Large amounts of organic aggregates and faecal pellets were collected during the bloom. The aggregates were rich in carbohydrates and mineral grains and had similar rates of sedimentation (900 to 2 100 m d-1) to those of the faecal pellets (1 000 to 2 000 m d-1). The results of mineralogical and organic chemical analyses indicate the potential effect of these mucus-rich aggregates on local biogeochemical fluxes.Type of Medium: Electronic ResourceURL: -
18Articles: DFG German National LicensesStaff View
ISSN: 1432-1912Keywords: Catechol oestrogens ; Catecholamines ; O-Methylation ; COMT ; Extraneuronal uptake ; IsoprenalineSource: Springer Online Journal Archives 1860-2000Topics: MedicineNotes: Summary 1. In the present study we investigated the O-methylation of catechol oestrogens by intact rabbit thoracic aorta and subcellular fractions thereof. 2. The O-methylation of 2-hydroxyoestradiol (2OHE2) and 2-hydroxyoestriol (2OHE3) displayed saturation kinetics in the intact tissue. The apparent K m and V max values for the O-methylation of 2OHE2 were determined to be 0.91 μmol/l and 104 pmol g−1 min−1, respectively, when 2OHE2 was used as substrate; and 1.14 μmol/l and 188 pmol g−1 min−1 when 2OHE3 was used as substrate. 3. The inhibitors of the extraneuronal uptake process (viz; phenoxybenzamine 33 μmol/l; normetanephrine, 46 μmol/l; and deoxycorticosterone acetate 27 μmol/l) failed to inhibit the O-methylation of either 2OHE2 (3.4 μmol/l) or 2OHE3 (3.4 μmol/l) in intact segments of the rabbit thoracic aorta. 4. (-)-Isoprenaline (40 μmol/l) abolished the O-methylation of 2OHE2 (3.4 μmol/l) and markedly reduced that of 2OHE3 (3.4 μmol/l). Pretreatment of tissues with phenoxybenzamine (33 μmol/l) partially restored the O-methylation of 2OHE2 and 2OHE3 in the presence of (-)-isoprenaline (40 μmol/l). 5. The O-methylation of 2OHE2 (5 μmol/l) was significantly reduced in segments of aorta in which the endothelium was removed. The latter reduction could not be attributed to damage to components of the vessel media. 6. The O-methylation of 2OHE2 and (-)-isoprenaline by subcellular fractions of the rabbit aorta also was examined. Both the microsomal and cytosolic fractions were shown to O-methylate 2OHE2 and (-)-isoprenaline, providing evidence for the existence of membrane-bound and soluble forms of COMT in the rabbit aorta. 7. The O-methylation of 2OHE2 by cytosolic and microsomal fractions of the aorta was determined and compared to that of (-)-isoprenaline. The kinetic constants for the O-methylation of 2OHE2 by cytosolic (K m: 0.27 μmol/l; V max: 112 pmol g−1 min−1) and microsomal (K m: 0.15 μmol/l; V max: 161 pmol g−1 min−1) fractions were similar. In contrast, the kinetic constants for the O-methylation of isoprenaline by cytosolic (K m: 121 μmol/l; V max: 174 pmol g−1 min−1) and membranal (K m: 0.91 μmol/l; V max: 105 pmol g−1 min−1) fractions were very different. 8. It is concluded that catechol oestrogens are excellent substrates for catechol-O-methyltransferase (COMT) in the rabbit aorta. Their O-methylation can occur in endothelial structures as well as in the smooth muscle-containing medial sections of the vessel. Moreover, the catechol oestrogens gain entry to sites of O-methylation by a process independent of extraneuronal uptake; this process is assumed to be diffusion. The results high-light the role of membrane-bound COMT in the O-methylation of isoprenaline and both membrane-bound and soluble COMT in the O-methylation of catechol oestrogens.Type of Medium: Electronic ResourceURL: -
19Articles: DFG German National LicensesStaff View
ISSN: 1573-2673Source: Springer Online Journal Archives 1860-2000Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision MechanicsType of Medium: Electronic ResourceURL: