bluuebunny/crossref_metadata_2025_split huggingface dataset:
Die Dehydratisierung der Camphenhydrat‐carbonsäure‐(1)
Authors: Hoyer Hans L. 
Published: May 2007

AbstractBeim Erwärmen von Camphenhydrat‐carbonsäure‐(1) mit verd. Schwefelsäure wurde neben Camphen‐carbonsäure‐(1) Camphen‐carbonsäure‐(4) und 2‐Oxy‐camphan‐carbonsäure‐(4) eine noch unbekannte Carbonsäure, C11H16O2, erhalten, deren Konstitution aufgeklärt wird. Es werden präparativ gangbare Wege zur Herstellung der verschiedenen Umwandlungsprodukte von Camphenhydrat‐carbon‐säure‐(1) angegeben.
Reduktion des N‐Methyl‐pseudostrychnins und verwandter Verbindungen mit Lithiumaluminiumhydrid (VIII. Mitteil. über Strychnos‐Alkaloide)
Authors: Boit Hans‐G. , Paul Lieselotte 
Published: May 2007

AbstractLithiumaluminiumhydrid reduziert im N‐Methyl‐pseudostrychnin (I) und N‐Methyl‐pseudobrucin (III) sowohl die Lactam‐als auch die durch andere Reduktionsmittel nicht angreifbare Keto‐Gruppe unter Bildung der Alkoholbasen VI bzw. VII, die auch aus N‐Methyl pseudostrychnidin (II) bzw. N‐Methyl‐pseudobrucidin (IV) durch Umsetzung mit Lithiumaluminiumhydrid erhältlich sind. Die Reduktion des N‐Methyl‐isopseudostrychnidins (IX) führt analog der von II und IV zu der Alkoholbase XI; N‐Methyl‐isopseudostrychnin (VIII) liefert hingegen eine Base der wahrscheinlichen Konstitution X.
Über pflanzliche Herzgifte, XXXII. Mitteil.1): Über die herzwirksamen Glykoside der Wurzeln von Evonymus atropurpurea (Jacq.)
Authors: Tschesche Rudolf , Wirtz Sophie , Snatzke Günther 
Published: May 2007

AbstractIn den Wurzeln von Evonymus atropurpurea (Jacq.) konnten vier Cardenolidglykoside nachgewiesen werden. Nach Luizym‐Spaltung lassen sich Digitoxigenin und ein Digitoxigenin‐monodigitoxosid isolieren, Hydrolyse mit Strophanthobiase ergibt Evatromonosid, das als Digitoxigenin‐β‐D‐digitoxosid‐(1.5) erkannt wurde.
Notiz über einige Derivate der Thiodiglykolsäure
Authors: Schurz Josef , Kromer Günther 
Published: May 2007

AbstractDurch Umsetzung von Chloressigsäure‐Derivaten mit Natriumsulfid werden einige Thiodiglykolsäure‐Abkömmlinge dargestellt. Ihre UV‐Spektren werden mitgeteilt.
Metallorganische Innerkomplexe; II. Mitteil.1): γ‐Äthylmercaptopropyl‐diäthyl‐aluminium
Authors: Bähr Gerhard , Müller Gerhardt Ernst 
Published: May 2007

AbstractAls weiterer Vertreter metallorganischer Innerkomplexe wurde das γ‐Äthylmercaptopropyl‐diäthyl‐aluminium auf zwei Wegen synthetisiert und seine Konstitution ermittelt. Kurze quantitative Angaben über den Komplex Trimethylaluminium‐dimethylsulfid.
Beiträge zur Chemie des Schwefelkohlenstoffs und Selenkohlenstoffs, I. Mitteil.: Salze der Cyan‐dithioameisensäure
Authors: Bähr Gerhard , Schleitzer Gerhard 
Published: May 2007

AbstractSchwefelkohlenstoff addiert in geeigneten Lösungsmitteln dissoziable Cyanide zu Salzen der Cyan‐dithioameisensäure, NC·C(S)SMe. Nur in Dimethylformamid als Reaktionsmedium gelang die Isolierung der farbigen Cyan‐dithioformiate von Natrium, Kalium, Thallium (I) und Tetraäthylammonium in analytisch definierter und kristallisierter Form – die beiden Alkalisalze kristallisieren mit Kristall‐Dimethylformamid. Gemeinsam, wenn auch graduell verschieden, ist diesen Salzen die ungewöhnlich leichte Abgabe von elementarem Schwefel, die bisher auch der Isolierung reiner, monomerer Ester (als tiefrote Öle beobachtet) im Wege steht. Nach orientierenden Versuchen setzen sich Cyanide analog mit Selenkohlenstoff um, ebenso die den Cyaniden isosteren Monometallacetylide, MeC·CH, mit Schwefelkohlenstoff.
Rhodomycinone und Iso‐rhodomycinone, Rhodomycine, IV. Mitteil.1): Antibiotica aus Actinomyceten XXXIII. Mitteil.1)
Authors: Brockmann Hans , Franck Burchard 
Published: May 2007

AbstractRhodomycinone und Iso‐rhodomycinone, die Chromophore der Rhodomycine bzw. Iso‐rhodomycine, kommen neben diesen in der Kulturflüssigkeit und im Mycel von Streptomyces purpurascens vor. β‐ und ϵ‐Rhodomycinon sowie ϵ‐Iso‐rhodomycinon wurden aus Kulturmaterial kristallisiert abgetrennt.β‐Rhodomycinon C18H16O7, dessen Konstitution weitgehend aufgeklärt werden konnte, und ϵ‐Rhodomycinon C21H22O8 sind Derivate des 1.4.5‐Trioxy‐anthrachinons, ϵ‐Iso‐rhodomycinon C20H20O9 ist ein Abkömmling des 1.4.5.8‐Tetraoxy‐anthrachinons.
Über Sauerstoffradikale, IV. Mitteil.1): Disproportionierung und Komproportionierung von Sauerstoffradikalen
Authors: Müller Eugen , Ley Kurt , Kiedaisch Wolfgang 
Published: May 2007

AbstractUnter der Einwirkung von Chlorwasserstoff oder Salzsäure disproportionieren die blauen und roten Aroxyle zu den entsprechenden substituierten Phenolen und den chinoliden Chloriden, wobei das rote Aroxyl infolge der Anwesenheit einer p‐ständigen Methoxygruppe sofort in das 2.6‐Di‐tert.‐butyl‐benzochinon‐(1.4) übergeht. In Umkehrung dieser Reaktion komproportionieren die geeigneten Ausgangsphenole und chinoliden Halogenverbindungen zu den betreffenden Aroxylen. Auf die Bedeutung der “Aryloxydform” – inneres Semichinon – zur Erklärung dieser Befunde wird hingewiesen.
Ein Derivat eines neuen heterocyclischen Siebenringsystems mit zwei Stickstoffatomen
Authors: Plieninger Hans , Nógrádi Inge 
Published: May 2007

AbstractDie roten Kristalle, die sich beim Lösen der Verbindung I in verd. Salzsäure bilden, werden als das Hydrochlorid eines heterocyclischen Siebenrings erkannt.
Versuche zur Darstellung von Benzyl‐ und p‐Nitrobenzylschwefelchloriden1)
Authors: Baganz Horst , Keßler Hellmuth 
Published: May 2007

AbstractDurch chlorierende Spaltung von p, p′‐Dinitro‐dibenzyldisulfid wurde statt des erwarteten p‐Nitrobenzylschwefelchlorides p‐Nitromonothiobenzoylchlorid erhalten, nachgewiesen als N‐Dialkylthioamid. Wurde die chlorierende Spaltung in Gegenwart von Alkohol durchgeführt, so entstand p‐Nitro‐benzylsulfochlorid.
Ion‐ and Atom‐Leaching Mechanisms from Palladium Nanoparticles in Cross‐Coupling Reactions
Authors: Gaikwad Anil V. , Holuigue Alexandre , Thathagar Mehul B. , ten Elshof Johan E. , Rothenberg Gadi 
Published: May 2007

AbstractLeaching of palladium species from Pd nanoparticles under CC coupling conditions was observed for both Heck and Suzuki reactions by using a special membrane reactor. The membrane allows the passage of palladium atoms and ions, but not of species larger than 5 nm. Three possible mechanistic scenarios for palladium leaching were investigated with the aim of identifying the true catalytic species. Firstly, we examined whether or not palladium(0) atoms could leach from clusters under non‐oxidising conditions. By using our membrane reactor, we proved that this indeed happens. We then investigated whether or not small palladium(0) clusters could in fact be the active catalytic species by analysing the reaction composition and the palladium species that diffused through the membrane. Neither TEM nor ICP analysis supported this scenario. Finally, we tested whether or not palladium(II) ions could be leached in the presence of PhI by oxidative addition and the formation of [PdIIArI] complexes. Using mass spectrometry, UV‐visible spectroscopy and 13C NMR spectroscopy, we observed and monitored the formation and diffusion of these complexes, which showed that the first and the third mechanistic scenarios were both possible, and were likely to occur simultaneously. Based on these findings, we maintain that palladium nanoparticles are not the true catalysts in CC coupling reactions. Instead, catalysis is carried out by either palladium(0) atoms or palladium(II) ions that leach into solution.
Overlapping human leukocyte antigen class I/II binding peptide vaccine for the treatment of patients with stage IV melanoma
Authors:   Melanoma Study Group of the Mayo Clinic Cancer Center, Celis Esteban 
Published: May 2007

AbstractBACKGROUND.MPS160 (GRAMLGTHTMEVTV) is a glycoprotein 100‐derived melanoma peptide that contains overlapping human leukemic antigen A2‐, DR53‐, and DQw6‐restricted T‐cell epitopes. In preclinical testing, MPS160 demonstrated superior immunization and antitumor activity. In this report, the authors present the results from a clinical trial that evaluated the safety and immunologic efficacy of the MPS160 vaccine in patients with metastatic melanoma.METHODS.Patients with stage IV melanoma were randomized to 1 of 3 treatment arms: 1) MPS160 in incomplete Freund adjuvant (Montanide ISA‐51); 2) MPS160 in Montanide ISA‐51 with 75 μg of granulocyte‐macrophage–stimulating factor (GM‐CSF); or 3) MPS160 in Montanide ISA‐51 with 100 μg of GM‐CSF. Vaccines were administered every 3 weeks until patients developed disease progression or severe toxicity. Patients were aged ≥18 years with metastatic melanoma and a good performance status. Exclusion criteria included pregnancy/nursing, brain metastases, and ongoing chemotherapy. Immunologic efficacy was ascertained by using tetramer and functional analysis of peripheral blood lymphocytes.RESULTS.None of the 28 patients exhibited objective tumor responses or severe toxicities. Four patients remained progression free for ≥100 days. Immunologic analysis was available for 21 patients. Laboratory data demonstrated 1) increased frequency of vaccine‐specific, nonfunctional cytotoxic T lymphocytes in 10 patients; 2) no differences in immunization efficacy among the treatment arms; and 3) evidence of systemic cytokine/immune dysfunction.CONCLUSIONS.Clinically, the MPS160 vaccine was ineffective. Phenotypic (tetramer) evidence of immunization was ineffective functionally and most likely was caused by global immune dysfunction, as illustrated by abnormal cytokine profiles in peripheral blood. In this report, the authors discuss possible implications of the current results on future cancer vaccine studies. Cancer 2007. © 2007 American Cancer Society.
Sex‐role reversal is reflected in the brain of African black coucals (Centropus grillii)
Authors: Voigt Cornelia , Goymann Wolfgang 
Published: May 2007

AbstractIn most bird species males compete over access to females and have elevated circulating androgen levels when they establish and defend a breeding territory or guard a mate. Testosterone is involved in the regulation of territorial aggression and sexual display in males. In few bird species the traditional sex‐roles are reversed and females are highly aggressive and compete over access to males. Such species represent excellent models to study the hormonal modulation of aggressive behavior in females. Plasma sex steroid concentrations in sex‐role reversed species follow the patterns of birds with “traditional” sex‐roles. The neural mechanisms modulating endocrine secretion and hormone–behavior interactions in sex‐role reversed birds are currently unknown. We investigated the sex differences in the mRNA expression of androgen receptors, estrogen receptor α, and aromatase in two brain nuclei involved in reproductive and aggressive behavior in the black coucal, the nucleus taeniae and the bed nucleus of the stria terminalis. In the bed nucleus there were no sex differences in the receptor or aromatase expression. In the nucleus taeniae, however, we show for the first time, that females have a higher mRNA expression of androgen receptors than males. These results suggest that the expression of agonistic and courtship behavior in females does not depend on elevated blood hormone levels, but may be regulated via increased steroid hormone sensitivity in particular target areas in the brain. Hence, aggression in females and males may indeed be modulated by the same hormones, but regulated at different levels of the neuroendocrine cascade. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007
Fatty acid ruminal metabolism and digestibility in cows fed perennial ryegrass
Authors: Doreau Michel , Rearte Daniel , Portelli Josiane , Peyraud Jean‐Louis 
Published: May 2007

AbstractThe ruminal metabolism and intestinal digestibility of fatty acids (FA) was studied in four mid‐lactation dairy cows fitted with ruminal and duodenal cannulae. The cows received fresh perennial ryegrass as sole feed. Two grasses were compared, differing in the soluble carbohydrate/nitrogen ratio (SC+/N– and SC–/N+ ratios). This ratio was modified by the combination of three factors: age of regrowth, N fertilisation and hour of cutting. The two grasses contained 12.5 and 20.7% of crude protein, and 24.6 and 13.7% of SC, respectively. The SC+/N– grass contained less FA [1.82 vs. 2.49% of dry matter (DM)] and a lower percentage of linolenic acid (60.9 vs. 65.6% of FA). As DM intake did not differ between treatments, FA intake was higher for the SC–/N+ treatment. The duodenal composition of FA revealed numerous isomers of 18:1 and conjugated and non‐conjugated isomers of 18:2. SC–/N+ treatment resulted in a higher duodenal flow of stearic, linoleic, and linolenic acids and of several intermediates of linolenic acid hydrogenation. This was a consequence of differences in intake. Intestinal digestibility of FA from both grasses was high (around 90%). The proportions of FA in plasma did not reflect with accuracy the differences in duodenal FA resulting from differences in ruminal metabolism.
Comparison of supercritical CO2 and hexane extraction of lipids from sorghum distillers grains
Authors: Wang Lijun , Weller Curtis L. , Schlegel Vicki L. , Carr Timothy P. , Cuppett Susan L. 
Published: May 2007

AbstractTotal yields and compositions of sorghum dried distillers grains with solubles (DDGS) lipids obtained by supercritical CO2 (SC‐CO2) extraction were compared with those obtained by recirculated solvent extraction (RSE) with hexane. The total yield of lipids obtained by SC‐CO2 extraction at 27.5 MPa and 70 °C was 150 g lipids/kg DDGS, while the yield obtained by RSE with hexane at 69 °C was only 85 g lipids/kg DDGS. The contents of four high‐value compounds, i.e., policosanols, phytosterols, free fatty acids (FFA) and tocols, in the lipids obtained by SC‐CO2 extraction were 31.2, 15.6, 155.3 and 0.50 mg/g at 27.5 MPa and 70 °C, compared to 26.6, 9.6, 57.3 and 0.03 mg/g for RSE with hexane at 69 °C. The profiles of phytosterols and FFA in the sorghum DDGS lipids were relatively independent of the extraction methods and operating conditions.
Enantioselective Total Synthesis and Determination of the Absolute Configuration of the 4,6,8,10,16,18‐Hexamethyldocosane from Antitrogus parvulus
Authors: Herber Christian , Breit Bernhard 
Published: May 2007

AbstractThe absolute and relative configuration of the hexamethyldocosane (1) isolated from the cuticula of Antitrogus parvulus was determined based on the total synthesis of both diastereomers 1a and 1b in enantiomerically pure form. The synthesis demonstrates the utility of the o‐DPPB‐directed and copper‐mediated allylic syn‐substitution reaction with Grignard reagents for iterative deoxypropionate construction (o‐DPPB = ortho‐diphenylphosphanylbenzoyl). Additionally, the synthetic power of copper catalyzed sp3–sp3 cross coupling reactions by twofold employment for building block construction and as the final fragment coupling step in the course of a convergent total synthesis is shown. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Highly specific enrichment of phosphopeptides by zirconium dioxide nanoparticles for phosphoproteome analysis
Authors: Zhou Houjiang , Tian Ruijun , Ye Mingliang , Xu Songyun , Feng Shun , Pan Chensong , Jiang Xiaogang , Li Xin , Zou Hanfa 
Published: May 2007

AbstractLarge‐scale characterization of phosphoproteins requires highly specific methods for the purification of phosphopeptides because of the low abundance of phosphoproteins and substoichiometry of phosphorylation. A phosphopeptide enrichment method using ZrO2 nanoparticles is presented. The high specificity of this approach was demonstrated by the isolation of phosphopeptides from the digests of model phosphoproteins. The strong affinity of ZrO2 nanoparticles to phosphopeptides enables the specific enrichment of phosphopeptides from a complex peptide mixture in which the abundance of phosphopeptides is two orders of magnitude lower than that of nonphosphopeptides. Superior selectivity of ZrO2 nanoparticles for the enrichment of phosphorylated peptides than that of conventional immobilized metal affinity chromatography was observed. Femtomole phosphopeptides from digestion products could be enriched by ZrO2 nanoparticles and can be well detected by MALDI mass spectrometric analysis. ZrO2 nanoparticles were further applied to selectively isolate phosphopeptides from the tryptic digestion of mouse liver lysate for phosphoproteome analysis by nanoliter LC MS/MS (nano‐LC‐MS/MS) and MS/MS/MS. A total of 248 defining phosphorylation sites and 140 phosphorylated peptides were identified by manual validation using a series of rigid criteria.
Reproducible protein analysis by CE using linear polyacrylamide‐coated capillaries and hydrochloric acid rinsing
Authors: Suratman Adhitasari , Wätzig Hermann 
Published: May 2007

AbstractHydrochloric acid was investigated as a rinsing reagent to remove adsorbed proteins from linear polyacrylamide‐coated capillaries for electrophoresis. Three model proteins were used, namely cytochrome c as a basic protein, β‐lactoglobulin as an acidic protein, and β‐casein as a more easily denaturing protein. In order to regenerate capillary surfaces, they have been rinsed for 5 min with 2 M hydrochloric acid, 5 min with water, and then 30 min with buffer after every tenth run. It was found important to perform this regeneration procedure on time. The obtained results show good repeatability of the apparent EOF mobility with percentage RSDs below 3% (n = 60) in various cases. These good results were mainly confirmed in long‐term series with more than 200 runs each. Only very high concentrations (175 μM) of β‐lactoglobulin and β‐casein at pH 3.5 gave RSD% values above 5%. For these conditions, the further test of 85% m/m phosphoric acid as rinsing reagent showed a good repeatability of the apparent EOF mobilities as well.
Laccase from Trametes hirsuta Grown on Paper Cuttings: Application to Synthetic Dye Decolorization at Different pH Values
Authors: Rodríguez Couto S. 
Published: May 2007

AbstractThe potential of paper cuttings to produce laccase from Trametes hirsuta grown under solid‐state conditions was investigated. In addition, cultures were also grown on barley bran, a support commonly used in solid‐state fermentation (SSF), for comparison. Paper cutting cultures showed a maximum individual laccase activity of 7695 U/L on day 9. In addition, the ability to decolorize two structurally different dyes (Indigo Carmine and Lissamine Green B) by the extracellular liquid from both paper and barley bran cultures at pH values between 2 and 11 was analyzed. Laccase‐containing enzyme preparations from both cultures decolorized the dyes tested at pH values between 4 and 7 and, in addition, the laccase‐containing enzyme preparation from paper cutting cultures was also able to decolorize the dyes tested at alkaline pH values. This is a very interesting and novel result, since no decolorization by fungal laccases has been reported until recently at pH values higher than pH 7.
Enhanced Biosynthesis of Sulfide Oxidase by Arthrobacter Species Using Response Surface Methodology
Authors: Mohapatra B. R. , Gould W. D. , Dinardo O. , Papavinasam S. , Koren D. W. , Revie R. W. 
Published: May 2007

AbstractResponse surface methodology was used to develop a fermentation medium for the enhanced biosynthesis of a novel sulfide oxidase by Arthrobacter species strain FR‐3. The interactive effect of the medium components – such as glucose as the carbon source, and tryptone and yeast extract as the nitrogen source – was evaluated by a 23‐factorial central composite statistical design. Glucose and yeast extract were found to be the more influential medium constituents compared to tryptone since they had lower coefficients of linear effect, P‐values (< 0.02). The optimal fermentation medium components for the enhanced production of sulfide oxidase were recorded as glucose (8.98 g/L), tryptone (10.62 g/L) and yeast extract (7.3 g/L). Optimization of the medium constituents increased the experimental enzyme yield by 54 % compared to the unoptimized medium. This is the first report on the overproduction of sulfide oxidase by using response surface methodology.
B220 analysis with the local lymph node assay: proposal for a more flexible prediction model
Authors: Betts Catherine J. , Dearman Rebecca J. , Kimber Ian , Ryan Cindy A. , Gerberick G. Frank , Lalko Jon , Api Anne Marie 
Published: May 2007

AbstractThe mouse local lymph node assay (LLNA) has been developed and validated for the identification of chemicals that have the potential to induce skin sensitisation. In common with other predictive test methods the accuracy of the LLNA is not absolute and experience has revealed that a few chemicals, including for instance a minority of skin irritants, may elicit false‐positive reactions in the assay. To improve further the performance of the LLNA, and to eliminate or reduce false‐positives, there has been interest in an adjunct method in which the ability of chemicals to cause increases in the frequency of B220+ lymphocytes in skin‐draining lymph nodes is measured. Previous studies suggest that the use of B220 analyses aligned with the standard LLNA may serve to distinguish further between contact allergens and skin irritants. In the original predictive model, chemicals were regarded as being skin sensitisers if they were able to induce a 1.25‐fold or greater increase in the percentage of B220+ cells within lymph nodes compared with concurrent vehicle controls. Although this first prediction model has proven useful, in the light of more recent experience, and specifically as a consequence of some variability observed in the frequency of B220+ lymphocytes in nodes taken from vehicle control‐treated animals, it is timely now to reconsider and refine the model. As a result a new prediction model is proposed in which reliance on the use of absolute thresholds is reduced, and in which small changes in control values can be better accommodated. Copyright © 2007 John Wiley & Sons, Ltd.
Sperm nucleosomes disassembly is a requirement for histones proteolysis during male pronucleus formation
Authors: Iribarren Claudio , Morin Violeta , Puchi Marcia , Imschenetzky María 
Published: May 2007

AbstractWe had previously reported that a cysteine‐protease catalyzes the sperm histones (SpH) degradation associated to male chromatin remodeling in sea urchins. We found that this protease selectively degraded the SpH leaving maternal cleavage stage (CS) histone variants unaffected, therefore we named it SpH‐protease. It is yet unknown if the SpH‐protease catalyzes the SpH degradation while these histones are organized as nucleosomes or if alternatively these histones should be released from DNA before their proteolysis. To investigate this issue we had performed an in vitro assay in which polynucleosomes were exposed to the active purified protease. As shown in this report, we found that sperm histones organized as nucleosomes remains unaffected after their incubation with the protease. In contrast the SpH unbound and free from DNA were readily degraded. Interestingly, we also found that free DNA inhibits SpH proteolysis in a dose‐dependent manner, further strengthening the requirement of SpH release from DNA before in order to be degraded by the SpH‐protease. In this context, we have also investigated the presence of a sperm‐nucleosome disassembly activity (SNDA) after fertilization. We found a SNDA associated to the nuclear extracts from zygotes that were harvested during the time of male chromatin remodeling. This SNDA was undetectable in the nuclear extracts from unfertilized eggs and in zygotes harvested after the fusion of both pronucleus. We postulate that this SNDA is responsible for the SpH release from DNA which is required for their degradation by the cysteine‐protease associated to male chromatin remodeling after fertilization. J. Cell. Biochem. 103: 447–455, 2008. © 2007 Wiley‐Liss, Inc.