PubMed · 14863375
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L BORCHARDT. 1951-08-03. [On hyperhormony (multiple hormonal gland hyperfunction)].. https://pubmed.ncbi.nlm.nih.gov/14863375/
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In this study, microwave-assisted extraction (MAE) followed by gas chromatography (GC)-mass spectrometry (MS) analysis has been successfully developed for the simultaneous extraction and determination of contrasting endocrine disrupting chemicals (EDCs) including 17beta-estradiol, estrone, 17(alpha-ethynylestradiol, 16alpha-hydroxyestrone, 4-nonylphenol, 4-tert-octylphenol and bisphenol A in river sediments. For MAE, the effects of various parameters on the extraction efficiency were investigated. It is shown that the most efficient extraction (recovery > 74%) of the target compounds was achieved by using methanol as the solvent, an extraction temperature of 110 degrees C and 15 min of holding time. The cleanup of extracts was carried out by passage through a non-deactivated silica gel column, and a satisfactory elution efficiency of all compounds was achieved using a solvent mixture of ethyl acetate-hexane (4:6, v/v). The spiking experiments show that the mean recovery of the target compounds exceeded 61% at a spiking level of 5 ng/g dry mass, and 73% at 10, 40 and 100 ng/g dry mass with a good reproducibility. The method developed was applied to the determination of target EDCs in river sediments collected from rivers Uck and Ouse, UK, and results revealed the presence of the chosen compounds at low ng/g level.
A readily applicable method based on extraction by aqueous non-ionic surfactant solutions (Tween 80) and RP-HPLC coupled to fluorescence detection, has been developed for the simultaneous determination of the phenolic endocrine disrupting chemicals (EDCs) nonylphenol (NP), nonylphenol monoethoxylate (NP1EO) and nonylphenol diethoxylate (NP2EO) and bisphenol A (BPA) in environmental solid matrices. Clean up of sample extracts was performed on Si-C18 solid phase extraction (SPE) cartridges. The overall Tween 80 extraction-SPE-RP-HPLC procedure was validated for accuracy and precision by analyzing sediment samples spiked with known amounts of EDCs. Recoveries for NP, NP1EO, NP2EO and BPA and limits of detection are in agreement with conventional extraction methods. The developed methodology was successfully applied to the analysis of target compounds in Italian river sediments, river suspended matter and benthonic macroinvertebrate organisms (oligochaetes Lumbriculus variegatus). Results confirmed that this relatively simple procedure performed satisfactorily in the determination of phenolic EDCs in environmental solid matrices of different complexity and that it can be a suitable alternative method to conventional systems even for routine analyses.
The successive phases that make up both the local and systemic posttraumatic acute inflammatory response could represent the expression of three concatenated pathological or "primitive" functional systems with trophic properties: the nervous, immune, and endocrine ones. The nervous functional system would play an important role in the phenomenon of ischemia-reperfusion, which would be represented by nutrition by diffusion that is either anaerobic (ischemia) or with defective use of oxygen (reperfusion) and, thus, with a limited energy requirement. The immune functional system would be represented by the infiltration of the tissues by inflammatory cells and bacteria, which would become mediators in providing nutrition to the injured tissues. Although the use of oxygen would still be defective, hypermetabolism and fever would occur. In these inflammatory response phases, the lymphatic is the most important circulation. The endocrine functional system would be the most specialized and would have high energy requirements because it would be represented by the blood capillary-mediated nutrition. Highly specialized epithelial cells would already possess a perfected oxidative metabolism. The successive expression of these three functional systems during embryonic development and also during the evolutionary development of our species could explain why the inflammatory response is a ubiquitous mechanism that is common to multiple diseases, because it is an integrator of the ontogeny and phylogeny.