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21.
Romani R Corsi I Bonacci S Focardi S De Medio GE De Santis A Incarnato F Giovannini E Rosi G 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2006,145(2):188-196
We describe the acetylcholinesterase polymorphisms of two bivalve molluscs, Adamussium colbecki and Pecten jacobaeus. The research was aimed to point out differences in the expression of pesticide-resistant acetylcholinesterase forms in organisms living in different ecosystems such as the Ross Sea (Antarctica) and the Mediterranean Sea. In A. colbecki, distinct acetylcholinesterase molecular forms were purified and characterized from spontaneously soluble, low-salt-soluble and low-salt-Triton extracts from adductor muscle and gills. They consist of two non-amphiphilic acetylcholinesterases (G(2), G(4)) and an amphiphilic-phosphatidylinositol-membrane-anchored form (G(2)); a further amphiphilic-low-salt-soluble G(2) acetylcholinesterase was found only in adductor muscle. In the corresponding tissues of P. jacobaeus, we found a non-amphiphilic G(4) and an amphiphilic G(2) acetylcholinesterase; amphiphilic-low-salt-soluble acetylcholinesterases (G(2)) are completely lacking. Such results are related with differences in cell membrane lipid compositions. In both scallops, all non-amphiphilic AChEs are resistant to used pesticides. Differently, the adductor muscle amphiphilic forms are resistant to carbamate eserine and organophosphate diisopropylfluorophosphate, but sensitive to organophoshate azamethiphos. In the gills of P. jacobaeus, amphiphilic G(2) forms are sensitive to all three pesticides, while the corresponding forms of A. colbecki are sensitive to eserine and diisopropylfluorophosphate, but resistant to azamethiphos. Results indicate that organophosphate and/or carbamate resistant AChE forms are present in species living in far different and far away environments. The possibility that these AChE forms could have ensued from a common origin and have been spread globally by migration is discussed. 相似文献
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D Konopińska G Rosiński H Bartosz-Bechowski A Lesicki P Sujak W Sobótka 《International journal of peptide and protein research》1990,35(1):12-16
Six proctolin analogues (I-VI) modified in position 1 of the peptide chain by the following amino acids: homo-Arg, Gac, Gav, Gap, Phe (p-guanidino) and Orn, were synthesized by conventional liquid phase method. The myotropic activity of the obtained peptides was investigated in cardioexcitatory test on two insect species, cockroach, Periplaneta americana L., and yellow mealworm, Tenebrio molitor. 相似文献
26.
S. R. Schmolke K. Broeg S. Zander V. Bissinger P. D. Hansen N. Kress B. Herut E. Jantzen G. Krüner A. Sturm W. Körting H. von Westernhagen 《Helgoland Marine Research》1999,53(3-4):257-266
A comprehensive database, containing biological and chemical information, collected in the framework of the bilateral interdisciplinary
MARS project (”biological indicators of natural and man-made changes in marine and coastal waters”) during the years 1995–1997
in the coastal environment of the North Sea, was subjected to a multivariate statistical evaluation. The MARS project was
designated to combine a variety of approaches and to develop a set of methods for the employment of biological indicators
in pollution monitoring and environmental quality assessment. In total, nine ship cruises to four coastal sampling sites were
conducted; 765 fish and 384 mussel samples were analysed for biological and chemical parameters. Additional information on
the chemical background at the sampling sites was derived from sediment samples, collected at each of the four sampling sites.
Based on the available chemical data in sediments and black mussel (Mytilus edulis) a pollution gradient between the selected sites, was established. The chemical body burden of flounder (Platichthys flesus) from these sites, though, did not reflect this gradient equally clear. In contrast, the biological information derived from
measurements in fish samples displayed significant a regional as well as a temporal pattern. A multivariate bioindicator data
matrix was evaluated employing a factor analysis model to identify relations between selected biological indicators, and to
improve the understanding of a regional and temporal component in the parameter response. In a second approach, applying the
k-means algorithm on the data matrix, two significantly different clusters of samples, characterised by the current health
status of the fish, were extracted. Using this classification a temporal, and in the second order, a less pronounced spatial
effect was evident. In particular, during July 1996, a clear sign of deteriorating environmental conditions was extracted
from the biological data matrix.
Received: 20 June 1999 / Received in revised form: 8 November 1999 / Accepted: 8 November 1999 相似文献
27.
Vladimir Bresler Vera Bissinger Avigdor Abelson Halim Dizer Armin Sturm Renate Kratke Lev Fishelson Peter-Diedrich Hansen 《Helgoland Marine Research》1999,53(3-4):219-243
The intensive development of industry and urban structures along the seashores of the world, as well as the immense increase
in marine transportation and other activities, has resulted in the deposition of thousands of new chemicals and organic compounds,
endangering the existence of organisms and ecosystems. The conventional single biomarker methods used in ecological assessment
studies cannot provide an adequate base for environmental health assessment, management and sustainability planning. The present
study uses a set of novel biochemical, physiological, cytogenetic and morphological methods to characterize the state of health
of selected molluscs and fish along the shores of the German North Sea, as well as the Israeli Mediterranean and Red Sea.
The methods include measurement of activity of multixenobiotic resistance-mediated transporter (MXRtr) and the system of active
transport of organic anions (SATOA) as indicators of antixenobiotic defence; glutathione S-transferase (GST) activity as an
indicator of biotransformation of xenobiotics; DNA unwinding as a marker of genotoxicity; micronucleus test for clastogenicity;
levels of phagocytosis for immunotoxicity; cholinesterase (ChE) activity and level of catecholamines as indicators of neurotoxicity;
permeability of external epithelia to anionic hydrophilic probe, intralysosomal accumulation of cationic amphiphilic probe
and activity of non-specific esterases as indicators of cell/tissue viability. Complete histopathological examination was
used for diagnostics of environmental pathology. The obtained data show that the activity of the defensive pumps, MXRtr and
SATOA in the studied organisms was significantly higher in the surface epithelia of molluscs from a polluted site than that
of the same species from control, unpolluted stations, providing clear evidence of response to stress. Enhanced frequency
of DNA lesions (alkaline and acidic DNA unwinding) and micronucleus-containing cells was significantly higher in samples from
polluted sites in comparison to those from the clean sites that exhibited genotoxic and clastogenic activity of the pollutants.
In all the studied molluscs a negative correlation was found between the MXRtr levels of activity and the frequency of micronucleus-containing
hemocytes. The expression of this was in accordance with the level of pollution. The complete histopathological examination
demonstrates significantly higher frequencies of pathological alterations in organs of animals from polluted sites. A strong
negative correlation was found between the frequency of these alterations and MXRtr activity in the same specimens. In addition
to these parameters, a decrease in the viability was noted in molluscs from the polluted sites, but ChE activities remained
similar at most sites. The methods applied in our study unmasked numerous early cryptic responses and negative alterations
of health in populations of marine biota sampled from the polluted sites. This demonstrates that genotoxic, clastogenic and
pathogenic xenobiotics are present and act in the studied sites and this knowledge can provide a reliable base for consideration
for sustainable development.
Received: 2 March 1999 / Received in revised form: 2 August 1999 / Accepted: 3 August 1999 相似文献
28.
Paweł Marciniak Sebastian Grodecki Danuta Konopińska Grzegorz Rosiński 《Journal of peptide science》2008,14(3):329-334
We have examined the effects of the Led-NPF-I peptide (Ala-Arg-Gly-Pro-Gln-Leu-Arg-Leu-Arg-Phe-amide) and a series of ten analogues on the heart contractile activity of Tenebrio molitor and Zophobas atratus, and the structure-activity relationships for cardioactive action of Led-NPF-I were established. A video microscopy technique and computer-based method of data acquisition and analysis were used to study the action of the peptides on continuously perfused heart preparations. Cardiac activity was progressively inhibited by Led-NPF-I when the peptide concentrations were increased from 10(-9) to 10(-5) M. Substitution of the L-proline residue at position 4 of the native peptide with hydroxyproline, valine or D-proline caused a loss of cardioinhibitory activity. Also, replacement of arginine residues at all three positions 2, 7 and 9 with another basic amino acid histidine, reduces cardioinhibitory action of Led-NPF-I. Some modifications of the C-terminal residues, as the Phe(4-NO2)-, Phe(4-NH2)- and Phe(4-NMe2)-analogues, resulted in agonistic peptides with biological activity similar to that of the native peptide. However, three other C-terminal analogues tested [Tyr10]-, [D-Phe10]-Led-NPF-I, and Ala-Arg-Gly-Pro-Gln-Leu-Arg-Leu-Arg-Phe-OH were inactive in the heart bioassay, which suggests that this end of the amino acid chain may play an important role in bioactivity and interaction of the native peptide with its receptor on the myocardium. 相似文献
29.
A M Luciani A Rosi M T Maggiorella M Federico N Sulli P Verani G B Rossi V Viti L Guidoni 《FEBS letters》1991,285(1):11-16
Different strains of HIV susceptible lymphoblastoid cells have been infected by HIV-1 and examined by means of 1H NMR spectroscopy at different times after infection, taking advantage of the presence of high resolution lipid signals from the plasma membrane of tumor cells. A transient decrease in intensity of fatty acid signals, originated by changes in membrane structure, has been observed early after viral infection. Marked alterations in membrane-dependent steps of phospholipid synthesis can also be inferred by the observed transient depression in peaks from choline-based metabolites. Spectral modifications deriving from changes in lipid metabolism are also produced both in infected cells a few days after infection and in permanently infected cells. 1H NMR can, therefore, monitor structural and metabolic effects induced by HIV infection. 相似文献
30.