The occurrence of wildcat in the Polish Carpathian Mountains

The contemporary occurrence of wildcatFelis silvestris (Schreber, 1775) in the Polish part of the Carpathian Mountains was evaluated in 1998–2000 with personal inquiries in all forest inspectorates of Krosno and Kraków Regional Directorates of State Forests and five national parks (NP). Additional information on the presence of wildcat was collected by snow tracking in three winter seasons: 1998/1999 through 2000/2001. Wildcat presence was confirmed only for Bieszczady Mountains, Pogórze Przemyskie, and Beskid Niski Mountains (13 forest inspectorates and 2 national parks: Bieszczady NP and Magurski NP).     

Effect of pH on the interfacial tension of bilayer lipid membrane formed from phosphatidylcholine or phosphatidylserine

The effect of pH of an electrolyte solution on the interfacial tension of lipid membrane formed from phosphatidylcholine (PC) or phosphatidylserine (PS) was studied. The relationships were well described by an equation presented earlier based on the Gibbs isotherm but only in the proximity of the isoelectric point. Therefore, in this work models have been derived to describe the adsorption of the H(+) and OH(-) ions at lipid surfaces formed from PC or PS, which would reproduce changes in interfacial tension more correctly, particularly in the ranges distant from the isoelectric point. In one model, the surface is continuous with uniformly distributed functional groups constituting the centres of H(+) and OH(-) ion adsorption while in the other the surface is built of lipid molecules, free or with attached H(+) and OH(-) ions. In both models, the contributions of the individual lipid molecule forms to the interfacial tension of the bilayer were assumed to be additive.     

One melanocortin 4 and two melanocortin 5 receptors from zebrafish show remarkable conservation in structure and pharmacology

We report the cloning, genome mapping, functional expression, pharmacology and anatomical distribution of three melanocortin (MC) receptors from zebrafish (z). Phylogenetic analysis showed with high bootstrap support that these genes represent one MC4 receptor and two MC5 receptors. Chromosomal mapping showed conserved synteny between regions containing zMC4 and human (h) MC4 receptors, whereas the two zMC5 receptor genes map on chromosome segments in which the zebrafish has several genes with two orthologues of a single mammalian gene. It is likely that the two copies of zMC5 receptors arose through a separate duplication in the teleost lineage. The zMC4, zMC5a, and zMC5b receptors share 70-71% overall amino acid identity with the respective human orthologues and over 90% in three TM regions believed to be most important for ligand binding. All three zebrafish receptors also show pharmacological properties remarkably similar to their human orthologues, with similar affinities and the same potency order, when expressed and characterized in radioligand binding assay for the natural MSH) peptides alpha-, beta-, and gamma-MSH. Stimulation of transfected mammalian cells with alpha-MSH caused a dose-dependent increase in intracellular cAMP levels for all three zebrafish receptors. All three genes were expressed in the brain, eye, ovaries and gastrointestinal tract, whereas the zMC5b receptor was also found in the heart, as determined by RT-PCR. Our studies, which represent the first characterization of MC receptors in a nonamniote species, indicate that the MC receptor subtypes arose very early in vertebrate evolution. Important pharmacological and functional properties, as well as gene structure and syntenic relationships have been highly conserved over a period of more than 400 million years implying that these receptors participate in vital physiological functions.     

Isthmiophora Lühe, 1909 and Euparyphium Dietz, 1909 (Digenea: Echinostomatidae) re-defined,with comments on their nominal species

The validity of Isthmiophora Lühe, 1909 in relation to Euparyphium Dietz, 1909 is discussed and confirmed. Isthmiophora melis Schrank, 1788) [the type-species] and I. inermis (Fuhrmann, 1904) n. comb. are redescribed, and diagnoses are given for both genera, along with lists of their presently-accepted constituent species which are commented upon where necessary. A similar list of species previously allocated to these genera is also presented with comments on their current status. A key to the species of Isthmiophora is included. New combinations for species previously attributed to Euparyphium are: Isthmiophora inermis (Fuhrmann, 1904) n. comb., I. beaveri (Yamaguti, 1958) n. comb., I. lukjanovi (Chertkova, 1971) n. comb., I. citellicola (Kadenatsii in Skrjabin & Bashkirova, 1956) n. comb., I. hortensis (Asada, 1926) n. comb., Echinostoma pindchi (Khan & Chishti, 1985) n. comb., Echinoparyphium tripathii (Gupta & Gupta, 1982) n. comb., E. hirundonis (Fischthal & Kuntz, 1976) n. comb., and Hypoderaeum longitestis (Verma, 1936) n. comb. Species attributed to Euparyphium which are here considered species inquirendae are: E. lobata Farooq & Yousuf, 1986 sp. inq., E. ochoterenai Cerecero, 1943 sp. inq., E. sobolevi Ryzhikov, 1965 sp. inq., and E. taiwanense Fischthal & Kuntz, 1976 sp. inq.     

Ascorbyl palmitate as a carrier of ascorbate into neural tissues

We have investigated the hypothesis that a lipid-soluble derivative of ascorbic acid, ascorbyl-6-palmitate (AP), could serve as a carrier of ascorbate into neural tissues. Ascorbate could then exert its physiological effects in the biomembranes that are the target sites of the cellular signaling pathways which are normally hardly accessible to this water-soluble compound. The potential role of AP would require that it penetrates into tissues. The major objective of the study was to determine whether ascorbate could be recovered from cerebral cortex and carotid body tissues, both sensitive to the hypoxic stimulus, after AP given by gavage. Biological samples were analyzed by HPLC for the determination of ascorbate. We found that ascorbate was recovered from the tissues studied. Its content was higher in both tissues, by nearly an order of magnitude, after ingestion of AP than after ingestion of ascorbic acid, and the ascorbate level was higher in the carotid body than in the cortex. Hypoxia decreased the ascorbate content which implies physiological activity of ascorbate carried alongside the AP molecule. The lipophilic AP was able to cross biological barriers and satisfied the tissue demand for ascorbate better than the hydrophilic form. AP should be considered as the preferred form of transport of ascorbate into neural tissues. The results of this study suggest wider pharmacological applications of ascorbyl palmitate.     

MRP1-transfected cells do not show increased resistance against oxidative stress

Sensitivity of V79 Chinese hamster cells and V79 cells transfected with human MRP1 gene to several agents inducing oxidative stress was compared. Cells overexpressing MRP1 did not show increased resistance to tert-butyl hydroperoxide, diamide, paraquat, menadione, dichromate and carmustine as estimated by cell survival and DNA damage assessed by comet assay. These findings suggest that overexpression of MRP1 does not confer increased resistance to oxidative stress.     

Spectral properties of phthalocyanines incorporated into resting and stimulated human peripheral blood cells

Human peripheral blood cells stimulated by phytohemagglutinin (which serve as a model of cancerous cells) and resting cells were incubated in dimethyl sulfoxide solutions of various phthalocyanines. In order to diminish the influence of atmospheric oxygen the cells were embedded in a polymer (polyvinyl alcohol) film. Fluorescence spectra of the samples were measured over two regions of excitation wavelengths: at 405 nm (predominant absorption of the cell material) and in the regions of strong absorption of phthalocyanines (at about 605 nm and 337 nm). The intrinsic emission of cell material became changed as a result both of cells' stimulation and of incubation of cells in dye solution. In most cases the stimulated cells when stained by dye exhibited higher long wavelength fluorescence intensity than resting cells. This suggests higher efficiency of dye incorporation into cancerous cells than into healthy cells. The absorption spectra of samples were also measured. The spectra of various phthalocyanines in incubation solvent, in polymer and in the cells embedded in polymer, were compared. The comparison of properties of the cells stimulated for different time periods enabled to establish the conditions of stimulation creating a population of cells incorporating a large number of sensitizing molecules.     

Regulation of malonyl-CoA concentration and turnover in the normal heart

The goal of this study was to test the relationship between malonyl-CoA concentration and its turnover measured in isolated rat hearts perfused with NaH(13)CO(3). This turnover is a direct measurement of the flux of acetyl-CoA carboxylation in the intact heart. It also reflects the rate of malonyl-CoA decarboxylation, i.e. the only known fate of malonyl-CoA in the heart. Conditions were selected to result in stable malonyl-CoA concentrations ranging from 1.5 to 5 nmol.g wet weight-(1). The malonyl-CoA concentration was directly correlated with the turnover of malonyl-CoA, ranging from 0.7 to 4.2 nmol.min(-) (1).g wet weight(-1) (slope = 0.98, r(2) = 0.94). The V(max) activities of acetyl-CoA carboxylase and of malonyl-CoA decarboxylase exceeded the rate of malonyl-CoA turnover by 2 orders of magnitude and did not correlate with either concentration or turnover of malonyl-CoA. However, conditions of perfusion that increased acetyl-CoA supply resulted in higher turnover and concentration, demonstrating that malonyl-CoA turnover is regulated by the supply of acetyl-CoA. The only condition where the activity of malonyl-CoA decarboxylase regulated malonyl-CoA kinetics was when the enzyme was pharmacologically inhibited, resulting in increased malonyl-CoA concentration and decreased turnover. Our data show that, in the absence of enzyme inhibitors, the rate of acetyl-CoA carboxylation is the main determinant of the malonyl-CoA concentration in the heart.     

In vitro modeling of fatty acid synthesis under conditions simulating the zonation of lipogenic [13C]acetyl-CoA enrichment in the liver

In the companion report (Bederman, I. R., Reszko, A. E., Kasumov, T., David, F., Wasserman, D. H., Kelleher, J. K., and Brunengraber, H. (2004) J. Biol. Chem. 279, 43207-43216), we demonstrated that, when the hepatic pool of lipogenic acetyl-CoA is labeled from [13C]acetate, the enrichment of this pool decreases across the liver lobule. In addition, estimates of fractional synthesis calculated by isotopomer spectral analysis (ISA), a nonlinear regression method, did not agree with a simpler algebraic two-isotopomer method. To evaluate differences between these methods, we simulated in vitro the synthesis of fatty acids under known gradients of precursor enrichment, and known values of fractional synthesis. First, we synthesized pentadecanoate from [U-13C3]propionyl-CoA and four gradients of [U-13C3]malonyl-CoA enrichment. Second, we pooled the fractions of each gradient. Third, we diluted each pool with pentadecanoate prepared from unlabeled malonyl-CoA to simulate the dilution of the newly synthesized compound by pre-existing fatty acids. This yielded a series of samples of pentadecanoate with known values of (i) lower and upper limits for the precursor enrichment, (ii) the shape of the gradient, and (iii) the fractional synthesis. At each step, the mass isotopomer distributions of the samples were analyzed by ISA and the two-isotopomer method to determine whether each method could correctly (i) detect gradients of precursor enrichment, (ii) estimate the gradient limits, and (iii) estimate the fractional synthesis. The two-isotopomer method did not identify gradients of precursor enrichment and underestimated fractional synthesis by up to 2-fold in the presence of gradients. ISA uses all mass isotopomers, correctly identified imposed gradients of precursor enrichment, and estimated the expected values of fractional synthesis within the constraints of the data.     

Redescriptions of Aphanurus stossichii (Monticelli, 1891) and A. virgula Looss, 1907 (Digenea: Hemiuridae)

Aphanurus stossichii (Monticelli, 1891) is redescribed from Boops boops (L.) from various localities in the NE Atlantic region (off Spain), the Mediterranean (off Spain and Turkey) and the Black Sea (off Bulgaria). The material from the Atlantic coast of Spain showed differences in egg-size and shape and a characteristic ornamentation of the anterior third of the hermaphroditic duct. A comparison with samples from B. boops collected off Antalya (Turkey) and off the Bulgarian Black Sea coast revealed a considerable size variation and confirmed the presence of tubercles in the terminal part of the hermaphroditic duct. A. virgula Looss, 1907, previously considered a synonym of A. stossichii, is redescribed on the basis of voucher material from Engraulis encrasicolus ponticus Alexandrov collected off the Bulgarian Black Sea coast and previously identified as A. stossichii. A. virgula can be distinguished from A. stossichii by its smaller size and substantially lower range limits for all metrical features, the more posterior position of the base of sinus-sac, and the eggs being less numerous and larger in relation to the size of the body and gonads.