Catalytic gas-phase glycerol processing over SiO2-, Cu-, Ni-and Fe-supported Au nanoparticles

In this study, we investigated different metal pairings of Au nanoparticles (NPs) as potential catalysts for glycerol dehydration for the first time. All of the systems preferred the formation of hydroxyacetone (HYNE). Although the bimetallics that were tested, i.e., Au NPs supported on Ni, Fe and Cu appeared to be more active than the Au/SiO2 system, only Cu supported Au NPs gave high conversion (ca. 63%) and selectivity (ca. 70%) to HYNE

Human Vav1 Expression in Hematopoietic and Cancer Cell Lines Is Regulated by c-Myb and by CpG Methylation

Vav1 is a signal transducer protein that functions as a guanine nucleotide exchange factor for the Rho/Rac GTPases in the hematopoietic system where it is exclusively expressed. Recently, Vav1 was shown to be involved in several human malignancies including neuroblastoma, lung cancer, and pancreatic ductal adenocarcinoma (PDA). Although some factors that affect vav1 expression are known, neither the physiological nor pathological regulation of vav1 expression is completely understood. We demonstrate herein that mutations in putative transcription factor binding sites at the vav1 promoter affect its transcription in cells of different histological origin. Among these sites is a consensus site for c-Myb, a hematopoietic-specific transcription factor that is also found in Vav1-expressing lung cancer cell lines. Depletion of c-Myb using siRNA led to a dramatic reduction in vav1 expression in these cells. Consistent with this, co-transfection of c-Myb activated transcription of a vav1 promoter-luciferase reporter gene construct in lung cancer cells devoid of Vav1 expression. Together, these results indicate that c-Myb is involved in vav1 expression in lung cancer cells. We also explored the methylation status of the vav1 promoter. Bisulfite sequencing revealed that the vav1 promoter was completely unmethylated in human lymphocytes, but methylated to various degrees in tissues that do not normally express vav1. The vav1 promoter does not contain CpG islands in proximity to the transcription start site; however, we demonstrated that methylation of a CpG dinucleotide at a consensus Sp1 binding site in the vav1 promoter interferes with protein binding in vitro. Our data identify two regulatory mechanisms for vav1 expression: binding of c-Myb and CpG methylation of 5′ regulatory sequences. Mutation of other putative transcription factor binding sites suggests that additional factors regulate vav1 expression as well

Behandlung von Erkältungskrankheiten mit einem komplementärmedizinischen Ansatz - ein Erfahrungsbericht aus der fachärztlichen Praxis

Bei Erkältungskrankheiten spielen komplementärmedizinische Ansätze in der Praxis eine erhebliche Rolle, doch steht eine wissenschaftliche Aufarbeitung der dabei gewonnenen Erfahrungen, die eine bessere Einschätzung des Nutzens dieser Ansätze in der Versorgungsrealiät erlauben würde, vielfach aus.Ziel dieses Erfahrungsberichtes war, einen solchen Ansatz am Beispiel eines Komplexhomöopathikums zu dokumentieren. Hierzu wurden retrospektiv Daten zu 200 Patienten erhoben, welche bis 2007 mit dem Präparat STW 11 (Influex®), einer Kombination aus Dilutionen von Echinacea, Aconitum napellus, Apis mellifica und Lachesis muta, behandelt und bis zum Jahr 2009 nachbeobachtet worden waren.Die Patienten wiesen mindestens die Symptome verstopfte Nase und Schleimstraße im Rachenraum auf. Dokumentiert wurden Variablen aus den Bereichen Fieber/Schmerz, Husten, Hals und Nase (9-Punkt-Likert-Skala), Krankheitsdauer sowie CRP-Wert. Weiterhin konnte die Anzahl der krankheitsbedingten Fehltage und die Anzahl der Infekte nach der Influex-Therapie während der zweijährige Nachbeobachtungsphase im Vergleich zum Zeitraum davor eingeschätzt werden.Das Präparat zeigte insbesondere bei leichterer Symptomatik, z.B. einer beginnenden Erkältung, gute Wirksamkeit, so dass im Mittel nach weniger als 4 Tagen Remission (Gesamtscorewert <=3) eintrat. Die Zahl der krankheitsbedingten Fehltage sank im Zeitraum von 24 Monaten nach der Therapie mit Influex um 6,5 Tage, die Zahl der Infekte um den Faktor 2,6. Unerwünschte Arzneimittelwirkungen wurden nicht beobachtet.Die Studie belegt demnach am Beispiel eines Komplexhomöopathikums, STW 11, dass ein komplementärmedizinischer Ansatz insbesondere für Patienten mit ersten Erkältungssymptomen geeignet und sehr gut verträglich ist.Unterstützt durch: Steigerwald Arzneimittelwerk Gmb

The histone deacetylase inhibitor trichostatin A mediates upregulation of 5-lipoxygenase promoter activity by recruitment of Sp1 to distinct GC-boxes

The histone deacetylase inhibitor trichostatin A (TsA) potently induces 5-lipoxygenase (5-LO) promoter activity in reporter gene assays as well as 5-LO mRNA expression. We identified two proximal Sp1/Sp3 binding sites in the 5-LO gene promoter mediating the TsA effect in both 5-LO-negative HeLa cells and in 5-LO expressing Mono Mac 6 (MM6) cells, the tandem GC-boxes, by contrast, were not important for the TsA effect. TsA neither altered the protein expression levels of Sp1/Sp3 nor of the histone deacetylases HDAC1/2, nor did it apparently change the protein complex formation by these factors. Also, treatment of cells with TsA did not change the binding affinity of Sp1/Sp3 in cell extracts, as tested by DAPA analysis using probes containing the proximal GC boxes. However, in the living cell TsA induced Sp1, Sp3 and RNA polymerase II recruitment to the 5-LO promoter without changing the acetylation status of histone protein H4. Cotransfection studies suggest that both Sp1 and Sp3 can mediate the TsA effect. This is the first report demonstrating that Sp3 is involved in the regulation of 5-LO promoter activity. In summary, we show that TsA increases 5-LO promoter activity by the enhanced recruitment of Sp1 and Sp3 to the 5-LO promoter

Synthesis and application of fatty acid derived templates for the preparation of mesostructured silica material

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Deacidification of used cooking oils by solvent extraction under lab scale and in a falling film contactor

International audienceThis work evaluated the pretreatment of used cooking oils (UCOs) via liquid-liquid extraction, both at laboratory and bench scales, under batch and continuous operation. Processed UCOs were collected in Bogotá, Colombia, and physical pretreatment was done by extraction with methanol and ethanol in a batch operation. The selected solvent was further tested in an intensified process using a packed falling film contactor in continuous operation. The effectiveness of the treatment was evaluated with respect to the change in the main targeted properties of UCO, namely acidity index, photometric color index, and content of polar compounds. Additional physicochemical properties of UCO were also tracked during extraction. The most effective pretreatment was achieved by using ethanol as solvent with a water content of 5% wt. This was tested in the continuous contactor using an oil:solvent mass ratio of 1:2, a mass flow of oil of 0.74 kg/h and a packing length of 1.07 m. In a single contact stage, a 51% acidity reduction, a 17% reduction in color index, and a 6.7% reduction in the content of polar compounds were achieved. Preliminary estimations for an industrial process indicate processing costs of 332 US$/t and a carbon footprint of CO2 2.17 kg CO2-eq/kg

Pre-treatment of used cooking oils for the production of green chemicals: A review

International audienceExploitation of waste lipids in the production of higher value-added and green chemicals will become a common practice in the future to enhance the sustainability of the oleochemical industry. However, waste lipids are highly heterogeneous and contain a large variety of impurities that can affect potential valorization routes. Thus, there is need for carry out refining processes to obtain suitable oleochemical feedstocks. This work reviews the available and potential technologies for the pre-treatment, purification and refining of waste lipids, emphasizing the transformation of used cooking oils (UCOs) into oleochemical raw materials. Initially, a description of the world generation and supply of UCOs is presented, and some potential valorization alternatives are reported. Then, the chemical nature and composition of typical UCOs is considered, and the main physicochemical properties are recognized in order to identify suitable separation processes for impurities removal. In particular, acidity and moisture reduction are priorities considering that they affect further thermal, chemical and biochemical transformations. Also, toxic compounds need to be reduced to enable the use as fermentation substrates, or as raw material for value-added application. Nitrogen-, phosphorus-, and sulfur-containing compounds as well as polar compounds must to be removed to enhance sensorial properties, and to avoid negative effects during subsequent transformations. Among the most popular up-grading methods, esterification, adsorption, solvent extraction, and distillation have been adopted industrially. Also, some intensification alternatives have been effectively implemented in UCO refining (e.g. reactive separations)