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41.
42.
Dr. Sufi Desrini Julien Ducloux Guillaume Hamion Prof. Charles Bodet Dr. Jérome Labanowski Prof. Mustofa Mustofa Prof. Titik Nuryastuti Prof. Christine Imbert Dr. Marion Girardot 《化学与生物多样性》2023,20(8):e202300130
The extracts of five invasive plants were investigated for antifungal and antibiofilm activities against Candida albicans, C. glabrata, C. krusei, and C. parapsilosis. The antifungal activity was evaluated using the microdilution assay and the antibiofilm effect by measurement of the metabolic activity. Ethanol and ethanol-water extracts of Reynoutria japonica leaves inhibited 50 % of planktonic cells at 250 μg mL−1 and 15.6 μg mL−1, respectively. Ethanol and ethanol-water extracts of Baccharis halimifolia inhibited >75 % of the mature biofilm of C. albicans at 500 μg mL−1. The essential oil (EO) of B. halimifolia leaves was the most active (50 % inhibition (IC50) at 4 and 74 μg mL−1against the maturation phase and 24 h old-biofilms of C. albicans, respectively). Oxygenated sesquiterpenes were the primary contents in this EO (62.02 %), with β-caryophyllene oxide as the major component (37 %). Aromadendrene oxide-(2), β-caryophyllene oxide, and (±)-β-pinene displayed significant activities against the maturation phase (IC50=9–310 μ mol l−1) and preformed 24 h-biofilm (IC50=38–630 μ mol l−1) of C. albicans with very low cytotoxicity for the first two compounds. C. albicans remained the most susceptible species to this EO and its components. This study highlighted for the first time the antibiofilm potential of B. halimifolia, its EO and some of its components. 相似文献
43.
Dr. F. Eberhardt 《Planta》1955,45(1):57-67
Zusammenfassung Die charakteristischen Züge der Atmung von reifenden Früchten werden beschrieben. Bei Blättern in der Entwicklungsperiode vor dem Laubfall konnte ein Atmungsverlauf festgestellt werden, der demjenigen reifender Früchte in wesentlichen Teilen entspricht. Das Phänomen des climacteric rise bei Früchten und Blättern wird verglichen. Es wird hervorgehoben, daß ein klimakterischer Atmungsanstieg nicht allein bei Früchten, die auf dem Lager reifen, sondern ebenso während der Baumreife auftritt. Die für die Reifungsatmung kennzeichnende Atmungskurve ergibt sich auch dann, wenn man die Atmungsintensität nicht wie üblich auf das Frischgewicht, sondern auf die Zahl der Früchte (bzw. auf die Blattfläche) bezieht. Der Anstieg der Atmungsintensität fällt bei Holunderfrüchten undParthenocissus-Blättern mit der Ausbildung der Anthocyanfarbstoffe zusammen. Während bei der Fruchtreifung der R Q häufig Werte über 1 erreicht, steigt der Quotient bei Blättern im Verlauf der Laubverfärbung nicht an. Neuere Vorstellungen über die Ursachen des climacteric rise werden diskutiert.Mit 5 Textabbildungen.Herrn Prof.M. Thomas, F. R. S., Newcastle-upon-Tyne, und Herrn Prof. Dr.K. Paech, Tübingen, möchte ich für Anregungen und Hinweise zu dieser Arbeit aufrichtig danken. 相似文献
44.
Melissa Pederson Mussell Carol B. Peterson Christine L. Weller Ross D. Crosby Martina de Zwaan James E. Mitchell 《Obesity (Silver Spring, Md.)》1996,4(5):431-439
Obese individuals with binge eating disorder (BED) differ from obese non-binge eating (NBE) individuals in a number of clinically relevant ways. This study examined attitudinal responses to various measures of body image in women seeking obesity treatment, by comparing NBE participants (n=80) to those with BED (n=48). It was hypothesized that women with BED would demonstrate greater attitudinal disturbance of body image compared to NBE individuals. It was further hypothesized that significant differences between groups would remain after statistically controlling for degree of depression. Consistent with the primary hypothesis, BED participants reported significantly increased attitudinal disturbance in body dissatisfaction and size perception compared to NBE participants. Although shared variance was observed between measures of depression and body image on some items, several aspects of increased body image disturbance remained after statistically controlling for depression. Treatment implications and recommendations for future research are discussed. 相似文献
45.
Christine L. Olsson Monique Graffe Mathias Springer John W. B. Hershey 《Molecular genetics and genomics : MGG》1996,250(6):705-714
To investigate the physiological roles of translation initiation factor IF3 and ribosomal protein L20 inEscherichia coli, theinfC, rpmI andrpIT genes encoding IF3, L35 and L20, respectively, were placed under the control oflac promoter/operator sequences. Thus, their expression is dependent upon the amount of inducer isopropyl thiogalactoside (IPTG) in the medium. Lysogenic strains were constructed with recombinant lambda phages that express eitherrpmI andrplT orinfC andrpmI in trans, thereby allowing depletion of only IF3 or L20 at low IPTG concentrations. At low IPTG concentrations in the IF3-limited strain, the cellular concentration of IF3, but not L20, decreases and the growth rate slows. Furthermore, ribosomes run off polysomes, indicating that IF3 functions during the initiation phase of protein synthesis in vivo. During slow growth, the ratio of RNA to protein increases rather than decreases as occurs with control strains, indicating that IF3 limitation disrupts feedback inhibition of rRNA synthesis. As IF3 levels drop, expression from an AUU-infC-lacZ fusion increases, whereas expression decreases from an AUG-infC-lacZ fusion, thereby confirming the model of autogenous regulation ofinfC. The effects of L20 limitation are similar; cells grown in low concentrations of IPTG exhibited a decrease in the rate of growth, a decrease in cellular L20 concentration, no change in IF3 concentration, and a small increase in the ratio of RNA to protein. In addition, a decrease in 50S subunits and the appearance of an aberrant ribosome peak at approximately 41–43S is seen. Previous studies have shown that the L20 protein negatively controls its own gene expression. Reduction of the cellular concentration of L20 derepresses the expression of anrplT-lacZ gene fusion, thus confirming autogenous regulation by L20. 相似文献
46.
Entomopathogenic nematodes of the Heterorhabditidae and Steinernematidae appear to be capable of long-distance dispersal and local migration. Their transmission strategies include both highly active seek-and-destroy behaviours and ambusher strategies, and they may be sensitive to sex-related factors in their own populations. Their host-finding abilities are poorly understood, despite the fact that these abilities are fundamental to their success as biocontrol agents in soil. Like the vast numbers of exotic hymenopterans and other natural enemies that have been released for biological control over the past century, they may be used in their ecologically competent wild-type form. On the other hand, because they are applied inundatively, they may be tailored, by breeding or transformation, to their intended purpose and to ecological incompetence, improving both their efficacy and their ecological safety. 相似文献
47.
Molecular basis of intercellular adhesion in the biofilm-forming Staphylococcus epidermidis 总被引:13,自引:3,他引:10
Christine Heilmann Oliver Schweitzer Christiane Gerke Nongnuch Vanittanakom Dietrich Mack Friedrich Götz 《Molecular microbiology》1996,20(5):1083-1091
The Staphylococcus epidermidis genes icaABC are involved in the synthesis of the polysaccharide intercellular adhesin (PIA), which is located mainly on the cell surface, as shown by immunofluorescence studies with PIA-specific antiserum. PIA was shown to be a linear β-1,6-linked glucosaminoglycan composed of at least 130 2-deoxy-2-amino-D-glucopyrano-syl residues of which 80–85% are N-acetylated, the rest being non-N-acetylated and positively charged. A transposon insertion in the icaABC gene cluster (ica, intercellular adhesion) led to the loss of several traits, such as the ability to form a biofilm on a polystyrene surface, cell aggregation, and PIA production. The mutant could be complemented by transformation with the IcaABC-carrying plasmid pCN27. Transfer of pCN27 into the heterologous host Staphylococcus carnosus led to the formation of large cell aggregates, the formation of a biofilm on a glass surface, and PIA expression. The nucleotide sequence of icaABC suggests that the three genes are organized in an operon and that they are co-transcribed from the mapped ica A promoter. Ica A contains four potential transmembrane helices, indicative of a membrane location. The deduced Ica A sequence shows similarity to those of polysaccharide-polymerizing enzymes, the most pronounced being with a Rhizobium meliloti N-acetylglucosaminyltransferase involved in lipo-chitin biosynthesis (22.5% overall identity and 37.4% overall similarity). This similarity suggests that Ica A has N-acetylglucosaminyltransferase activity in the formation 相似文献
48.
Kathleen P. Anderson Christine B. Kern Scott C. Crable Jon C. Neumann Jerry B. Lingrel 《Transgenic research》1996,5(4):245-255
Our interest in thecis-acting elements that promote the up-regulation of the globin gene has led to a systematic deletion analysis of portions of the globin gene in the context of the HS2 and globin gene using transgenic mice. In constructs that delete the 5 region to only 265 bp, high-level erythroid-specific expression was observed. Further deletion to 122 bp, however, results in significantly reduced expression levels A substitution of a minilocus control region for the single HS2 site was also produced, resulting in increased globin expression over that seen with the HS2 alone. These results are consistent with the presence of an enhancer-like element between –122 and –265. In addition, a construct in which the entire globin gene promoter was replaced by a thymidine kinase promoter was tested. Interestingly, no expression was detected in these transgenic mice. This may indicate the requirement for an erythroid-specific promoter to drive this gene. Finally, the 3 region of the globin gene was deleted in order to examine the effect of a previously defined 3 enhancer region. With deletion of this region, the expression of the human globin gene in transgenic mice is unchanged relative to the parental constructs. 相似文献
49.
Xavier Khawaja Non Evans Yvonne Reilly Christine Ennis Michael C. W. Minchin 《Journal of neurochemistry》1995,64(6):2716-2726
Abstract: The specific binding of [3H]WAY-100635 {N-[2-[4-(2-[O-methyl-3H]methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl)cyclohexane carboxamide trihydrochloride} to rat hippocampal membrane preparations was time, temperature, and tissue concentration dependent. The rates of [3H]WAY-100635 association (k+1 = 0.069 ± 0.015 nM?1 min?1) and dissociation (k?1 = 0.023 ± 0.001 min?1) followed monoexponential kinetics. Saturation binding isotherms of [3H]WAY-100635 exhibited a single class of recognition site with an affinity of 0.37 ± 0.051 nM and a maximal binding capacity (Bmax) of 312 ± 12 fmol/mg of protein. The maximal number of binding sites labelled by [3H]WAY-100635 was ~36% higher compared with that of 8-hydroxy-2-(di-n-[3H]-propylamino)tetralin ([3H]8-OH-DPAT). The binding affinity of [3H]WAY-100635 was significantly lowered by the divalent cations CaCl2 (2.5-fold; p < 0.02) and MnCl2 (3.6-fold; p < 0.05), with no effect on Bmax. Guanyl nucleotides failed to influence the KD and Bmax parameters of [3H]WAY-100635 binding to 5-HT1A receptors. The pharmacological binding profile of [3H]WAY-100635 was closely correlated with that of [3H]8-OH-DPAT, which is consistent with the labelling of 5-hydroxytryptamine1A (5-HT1A) sites in rat hippocampus. [3H]WAY-100635 competition curves with 5-HT1A agonists and partial agonists were best resolved into high- and low-affinity binding components, whereas antagonists were best described by a one-site binding model. In the presence of 50 µM guanosine 5′-O-(3-thiotriphosphate) (GTPγS), competition curves for the antagonists remained unaltered, whereas the agonist and partial agonist curves were shifted to the right, reflecting an influence of G protein coupling on agonist versus antagonist binding to the 5-HT1A receptor. However, a residual (16 ± 2%) high-affinity agonist binding component was still apparent in the presence of GTPγS, indicating the existence of GTP-insensitive sites. 相似文献
50.