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31.
This study describes the GC‐FID, GC/MS, GC‐O, and enantioselective GC analysis of the essential oil hydrodistilled from leaves of Lepechinica mutica (Lamiaceae), collected in Ecuador. GC‐FID and GC/MS analyses allowed the characterization and quantification of 79 components, representing 97.3% of the total sample. Sesquiterpene hydrocarbons (38.50%) and monoterpene hydrocarbons (30.59%) were found to be the most abundant volatiles, while oxygenated sesquiterpenes (16.20%) and oxygenated monoterpenes (2.10%) were the minor components. In order to better characterize the oil aroma, the most important odorants, from the sensorial point of view, were identified by Aroma Extract Dilution Analysis (AEDA) GC‐O. They were α‐Pinene, β‐Phellandrene, and Dauca‐5,8‐diene, exhibiting the characteristic woody, herbaceus, and earthy odors, respectively. Enantioselective GC analysis of Lmutica essential oil revealed the presence of twelve couples and two enantiomerically pure chiral monoterpenoids. Their enantiomeric excesses were from a few percent units to 100%. Moreover, the essential oil exhibited moderate in vitro activity against five fungal strains, being especially effective against Mcanis, which is a severe zoophilic dermatophyte causal agent of pet and human infections.  相似文献   
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Sponges are sessile marine invertebrates that can live for many years in the same location, and therefore, they have the capability to accumulate anthropogenic pollutants such as metals over a long period. Almost all marine sponges harbor a large number of microorganisms within their tissues. The Bacillus cereus strain Pj1 was isolated from a marine sponge, Polymastia janeirensis, and was found to be resistant to 100 μM HgCl2 and to 10 μM methylmercury (MeHg). Pj1 was also highly resistant to other metals, including CdCl2 and Pb(NO3)2, alone or in combination. The mer operon was located on the bacterial chromosome, and the volatilization test indicated that the B. cereus Pj1 was able to reduce Hg2+–Hg0. Cold vapor atomic absorption spectrometry demonstrated that Pj1 volatilized 80 % of the total MeHg that it was exposed to and produced elemental Hg when incubated with 1.5 μM MeHg. Pj1 also demonstrated sensitivity to all antibiotics tested. In addition, Pj1 demonstrated a potential for biosurfactant production, presenting an emulsification activity better than synthetic surfactants. The results of this study indicate that B. cereus Pj1 is a strain that can potentially be applied in the bioremediation of HgCl2 and MeHg contamination in aquatic environments.  相似文献   
34.
The amplification of Raman signals of the heteroaromatic cation 1-(N-methylpyrid-4-yl)-2-(N-methylpyrrol-2-yl)ethylene (PEP+)) bound to Au nanorods (NRs) was investigated at different excitation wavelengths to study the effect of the laser resonance with the absorption band of the PEP+ moiety and with the two plasmon oscillation modes of the NR. Two different PEP+ derivatives, differing in the length of the alkyl chain bearing the anchoring group, were used as target molecules. Raman spectra obtained exciting at 514 or at 785 nm (i.e., exciting the transverse or the longitudinal plasmon band) present a higher intensity than that at 488 nm suggesting a higher Raman amplification when the laser excitation wavelength is resonant with one of the two plasmon modes. Moreover, considering results of Discrete Dipole Approximation (DDA) calculations of the local field generated at the NR surface when either the transverse or the longitudinal plasmon modes are excited, we deduced that the resonance condition of the 514-nm laser excitation with the absorption band of the dye strongly contributes to the amplification of the Raman signal.  相似文献   
35.
The antithrombotic activity of pelrinone, a phosphodiesterase III inhibitor was examined in a canine model of coronary thrombosis that uses electrical current to injure the coronary endothelium. Ninety percent of vehicle treated animals developed complete coronary occlusion and thrombus mass was 32.0 +/- 5.8 mg. In a group of animals treated with zomepirac, 10 mg/kg i.v., included as a positive control, thrombus mass was decreased to 10.3 +/- 3.3 mg and incidence of occlusion was reduced to 37.5%. Pelrinone, 5.0 mg/kg i.v. decreased the incidence of occlusion to 50%, thrombus mass to 21.3 +/- 8.3 mg and inhibited platelet aggregation to collagen, ADP and arachidonic acid by 80%, 54% and 87% of baseline, respectively. When yohimbine, an alpha 2-adrenergic antagonist, was co-administered (2.0 mg/kg at the beginning of the experiment +0.5 mg/kg halfway through the experiment) with the same dose of pelrinone, thrombus mass was decreased to 1.0 +/- 0.5 mg and none of the animals developed coronary occlusion. Yohimbine administration by itself at 2.0-3.0 mg/kg showed no evidence of antithrombotic activity (thrombus mass = 32.8 +/- 8.0 mg, incidence of occlusion = 100%). This dose of yohimbine inhibited significantly ADP-induced aggregation in the presence of epinephrine. These results demonstrate that, even though this dose of pelrinone elicited near maximal inhibition of platelet aggregation, the concurrent administration of an alpha 2-adrenergic antagonist was able to potentiate markedly the phosphodiesterase inhibitor antithrombotic activity.  相似文献   
36.
Abstract

The authors describe the occurrence of Gonyaulax tamarensis Lebour bloom in the Adriatic Sea between 200 and 1000 m off the coast of Emilia-Romagna during the period of August 14-20 1982.  相似文献   
37.
Helichrysum genus consists of about 600 species widespread throughout the world, especially in South Africa and in the Mediterranean area. In this study the aroma profile (HS‐SPME) and the EO compositions of seven Helichrysum species (Hcymosum, Hodoratissimum, Hpetiolare, Hfontanesii, Hsaxatile, Hsanguineum, and Htenax) were evaluated. All the plants were grown in Italy under the same growth conditions. The volatile constituents, particularly monoterpenes, depended by the plant's genotype and ecological adaptation. This study represents the first headspace evaluation on the selected plants and the results evidenced that monoterpenes represented the main class of constituents in five of the seven species analysed (from 59.2% to 95.0%). The higher content in sesquiterpene hydrocarbons was observed in the Mediterranean species of Hsanguineum (68.0%). Only Hsaxatile showed relative similar abundance of monoterpenes and sesquiterpene hydrocarbons. The essential oil composition of the majority of examined species are characterised by high percentage of sesquiterpenes (especially β‐caryophyllene and δ‐cadinene) ranging from 51.3% to 92.0%, except for Hcymosum, Htenax, and Hsanguineum leaves where monoterpenes predominated (from 51.7% to 74.7%).  相似文献   
38.
Interleukin 6 (IL6), an inflammatory response protein has major implications in immune-related inflammatory diseases. Identification of aptamers for the IL6 protein aids in diagnostic, therapeutic, and theranostic applications. Three different DNA aptamers and their interactions with IL6 protein were extensively investigated in a phosphate buffed saline (PBS) solution. Molecular-level modeling through molecular dynamics provided insights of structural, conformational changes and specific binding domains of these protein–aptamer complexes. Multiple simulations reveal consistent binding region for all protein–aptamer complexes. Conformational changes coupled with quantitative analysis of center of mass (COM) distance, radius of gyration (Rg), and number of intermolecular hydrogen bonds in each IL6 protein–aptamer complex was used to determine their binding performance strength and obtain molecular configurations with strong binding. A similarity comparison of the molecular configurations with strong binding from molecular-level modeling concurred with Surface Plasmon Resonance imaging (SPRi) for these three aptamer complexes, thus corroborating molecular modeling analysis findings. Insights from the natural progression of IL6 protein–aptamer binding modeled in this work has identified key features such as the orientation and location of the aptamer in the binding event. These key features are not readily feasible from wet lab experiments and impact the efficacy of the aptamers in diagnostic and theranostic applications.  相似文献   
39.
We found that serum antibodies present in the serum of patients with motor neuron disease and neuropathy, which were previously shown to react with the oligosaccharide chain of ganglioside GM1(Neu5Ac), can be recognized and titred using theN-glycolylneuraminic acid containing monosialo-gangliotetrahexosylceramide, GM1(Neu5Gc), which is not a component of normal human cells. The antibody-antigen reaction was abolished by immunoabsorption with the free oligosaccharide chain. This result, together with the knowledge that these antibodies recognize several glycoconjugates, supports the conviction that these antibodies are non-specific for a gangliosidic structure.  相似文献   
40.
The present paper analyzes literature data dealing with the use of aminopolycarboxylates for chemical washing of heavy metals contaminated soils. The aim is to rationalize and organize the up-to-date knowledge of process dependence on different parameters, in order to give a contribution to the development of washing protocols applicable for process optimization. Process efficiency is found to be dependent on i) parameters related to soil composition, ii) parameters related to contaminant characteristics and iii) operating parameters. The effect that each of them, according to the reviewed experimental studies, has on process efficiency, is highlighted, and the interdependence among them is presented as a key point to understand the overall removal mechanism and therefore to calibrate its application case-by-case.  相似文献   
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