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131.
E. David Morgan Harald Jungnickel Johan Billen Fuminori Ito Jan Bergmann Bruno Gobin 《Biochemical Systematics and Ecology》2008
The chemistry of the exocrine glands of three species of the small and little-known ant subfamily Cerapachyinae has been examined for the first time. The mandibular glands of Cerapachys jacobsoni contained acetophenone and skatole, but some individuals contained, in addition, 4-methyl-3-heptanone and 3-octanol. The mandibular glands of the new species, presently known as Cerapachys sp. 15 of FI contained 4-methyl-3-heptanone, as the major substance but also 4-methyl-3-heptanol, methyl 6-ethylsalicylate, and traces of 4,5-dimethyl-4-hexen-3-one and homomanicone. The Dufour glands of C. jacobsoni contained a mixture of higher aldehydes, acetates and other esters, with a small amount of hydrocarbons, all in the range C11–C20. The Dufour glands of Cylindromyrmex whymperi contained a mixture of long-chain epoxides, the second ant species to display them. The sternal glands of C. whymperi contain a recruitment pheromone, but only partial identification of the contents was possible. The venom glands of all three species were devoid of volatile material. The Dufour glands of Cerapachys sp. 15 of FI and the mandibular glands of C. whymperi had no detectable volatile contents. 相似文献
132.
René R Balandrán-Quintana Ana Ma Mendoza-Wilson Gerardo Alvarez-Manilla Carl W Bergmann Irasema Vargas-Arispuro Miguel Angel Martínez-Téllez 《Biochemical and biophysical research communications》2002,290(1):577-584
The effect of pectic oligomers (OG) on ethylene biosynthesis, electrolyte leakage (EL), and CO(2) production was studied in discs excised from zucchini fruit (Cucurbita pepo L.) and stored at 20 or 2.5 degrees C. At 20 degrees C, OG enhanced ethylene biosynthesis and had a transient effect on decreasing EL, but showed little effect on respiratory rate; both the amount and size of the oligomer were important in changing both ethylene synthesis and EL. At 2.5 degrees C, OG increased both ethylene biosynthesis and respiratory rate with a maximum effect at 100 microg of oligomer and peaking at 6 h; shorter oligomers demonstrated an even greater effect on ethylene biosynthesis, but differences were smaller in respiratory rate. EL at 2.5 degrees C was affected most by 1 microg of OG and by monomeric galacturonic acid, with transient increases that peaked at 8 h. We suggest a signaling role for OG in the early steps of cold acclimation or chilling injury. 相似文献
133.
Yuri T. Yamamoto Nirmala Rajbhandari Xiaohong Lin Ben A. Bergmann Yufuko Nishimura Anne-Marie Stomp 《In vitro cellular & developmental biology. Plant》2001,37(3):349-353
Summary We developed efficient genetic transformation protocols for two species of duckweed, Lemna gibba (G3) and Lemna minor (8627 and 8744), using Agrobacterium-mediated gene transfer. Partially differentiated nodules were co-cultivated with Agrobacterium tumefaciens harboring a binary vector containing β-glucuronidase and nptII expression cassettes. Transformed cells were selected and allowed to grow into nodules in the presence of kanamycin. Transgenic
duckweed fronds were regenerated from selected nodules. We demonstrated that transgenic duckweed could be regenerated within
3 mo. after Agrobacterium-mediated transformation of nodules. Furthermore, we developed a method for transforming L. minor 8627 in 6 wk. These transformation protocols will facilitate genetic engineering of duckweed, ideal plants for bioremediation
and large-scale industrial production of biomass and recombinant proteins. 相似文献
134.
A Peretz T Papadopoulos D Willems A Hotimsky N Michiels V Siderova P Bergmann J Neve 《Journal of trace elements in medicine and biology》2001,15(2-3):175-178
Zinc takes part in the metabolism of bone as a constituent of the matrix and as an activator of several metallo-enzymes. Animal in vitro and in vivo studies strongly suggest that zinc supplementation could stimulate bone formation and inhibit bone resorption but data in humans remain rare. The biological effects of 50 mg zinc given orally as gluconate in 20 healthy male volunteers were investigated in a 12 weeks double-blind placebo-controlled randomized trial. To investigate bone turnover, total alkaline phosphatases activity (ALP), bone specific alkaline phosphatase activity (BAPE) and BAP mass (BAP-M) concentration were measured as parameters of bone formation while urine calcium and C-terminal collagen peptide were determined as parameters of bone resorption. Samples were obtained in fasting subjects at baseline and after 6 and 12 weeks. In zinc treated subjects, a significant increase was observed at least after 12 weeks in total ALP (p < 0.01), BAP-M (p < 0.05) and BAP-E (p < 0.02). These parameters did not significantly change in the placebo group. Urine zinc/creatinine ratio significantly increased after 6 (p < 0.03) and 12 weeks (p < 0.04) in the zinc-treated group and was significantly different from the placebo group (p < 0.002). There was no significant effect of zinc supplementation on parameters of bone resorption. In conclusion, zinc supplementation at supraphysiological doses increased parameters of bone formation in healthy men while parameters of bone resorption remained unchanged. 相似文献
135.
Effects of exogenous applied lipids being of microbial origin on the water use efficiency (WUE) and the biomass production have been studied in pot and field experiments using crop plants. Lipid mixtures extracted from the cells of Candida maltosa EH 15 increased the WUE (9…16%) and the grain yield (÷x = 10%) of the wheat and barley plants under dry conditions. The fatty acid fraction separated from the lipid mixtures also improved the WUE especially under stress (20…100%) and the biomass production. The phosphatide fraction emulsified with sulfonate containing solvents was not physiologically active. 相似文献
136.
137.
H Niedrich M Bienert B Mehlis J Bergmann P Oehme 《Acta biologica et medica Germanica》1975,34(3):483-489
C-terminal pentapeptides of eledoisin, physalaemin, and the substance P, when N-substituted with acetyl, halogenacetyl and other acyl residues, are increased in their action more than 100fold, reaching the activity of acylated hexa- and heptapeptides. The effect found with a number of compounds is interpreted as the influence of predominantly hydrophobic substituents upon the peptide sequence essential for the action. Polar groups in the acylic residue seem to cause additional increase in action. 相似文献
138.
Raimundo Wagner Souza Aguiar Suetonio Fernandes dos Santos Fabricio da Silva Morgado Sergio Donizeti Ascencio Magnólia de Mendon?a Lopes Kelvinson Fernandes Viana Julcemar Didonet Bergmann Morais Ribeiro 《PloS one》2015,10(2)
This study investigated the toxic effects of essential oils isolated from Siparuna guianensis against Aedes aegypti, Culex quinquefasciatus (eggs, larvae, pupae, and adult) and Aedes albopictus (C6/36) cells. The oviposition-deterring activity, egg viability, and repellence activity in the presence of different essential oils concentrations were determined. The essential oils showed high toxicity to all developmental stages of A. aegypti and C. quinquefasciatus. Furthermore, the oils also showed high repellent activity towards the adult stage of mosquitoes (0.025 to 0.550 μg/cm2 skin conferred 100% repellence up to 120 min) and in contact with cultured insect cells (C6/36) induced death possibly by necrosis. The results presented in this work show the potential of S. guianensis essential oils for the development of an alternative and effective method for the natural control of mosquitoes in homes and urban areas. 相似文献
139.
140.
Strain‐ and time‐dependent alterations in hepatic iron metabolism in a murine model of nonalcoholic steatohepatitis
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