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51.
Aida Begic Ana Djuric Milica Ninkovic Ivana Stevanovic Dragan Djurdjevic Milos Pavlovic 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):478-489
Examination of cadmium (Cd) toxicity and disulfiram (DSF) effect on liver was focused on oxidative stress (OS), bioelements status, morphological and functional changes. Male Wistar rats were intraperitoneally treated with 1?mg CdCl2/kg BW/day; orally with 178.5?mg DSF/kg BW/day for 1, 3, 10 and 21 days; and co-exposed from 22nd to 42nd day. The co-exposure nearly restored previously suppressed total superoxide dismutase (SOD), catalase (CAT) and increased glutathione peroxidase (GPx) activities; increased previously reduced glutathione reductase (GR) and total glutathione-S-transferase (GST) activities; reduced previously increased superoxide anion radical (O2·?) and malondialdehyde (MDA) levels; increased zinc (Zn) and iron (Fe), and decreased copper (Cu) (yet above control value), while magnesium (Mg) was not affected; and decreased serum alanine aminotransferases (ALT) levels. Histopathological examination showed signs of inflammation process as previously demonstrated by exposure to Cd. Overall, we ascertained partial liver redox status improvement, compared with the formerly Cd-induced impact. 相似文献
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Žanka Bojić-Trbojević Milica Jovanović Krivokuća Nikola Kolundžić Toshihiko Kadoya Ljiljana Radojčić 《Cell Adhesion & Migration》2016,10(1-2):179-188
ABSTRACTIn the course of embryo implantation extensive interaction of the trophoblast with uterine tissue is crucial for adequate trophoblast invasion. This interaction is highly controlled, and it has been pointed out that a specific glycocode and changes in glycosylation may be important for successful implantation and maintenance of pregnancy. Both uterine and trophoblast cells have been shown to express cell surface glycoconjugates and sugar binding proteins, such as mucins (MUC) and galectins (gals). An increasing number of studies have investigated potential candidates interacting in this process. However, knowledge about the biochemical nature of the interactions and their importance for trophoblast cell function, and, consequently, for pregnancy outcome are still lacking. This review is aimed at deliberating the possibility that mucins, as heavily glycosylated proteins, might be among the functionally relevant galectin ligands in human trophoblast, based on both published data and our original research. 相似文献
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Capsule: Using dummy experiments at nests of Great Reed Warblers Acrocephalus arundinaceus, we found no evidence to support the hypothesis that the contrasting black and white plumage colouration in Magpies Pica pica has evolved to reduce mobbing defensive attacks by potential prey species. We suggest instead that it might have evolved in the context of sexual selection or as a signal for flock formation. 相似文献
54.
David P. L. Toews Milica Mandic Jeffrey G. Richards Darren E. Irwin 《Evolution; international journal of organic evolution》2014,68(1):241-255
Discordance between mitochondrial and nuclear DNA has been noted in many systems. Asymmetric introgression of mitochondria is a common cause of such discordances, although in most cases the drivers of introgression are unknown. In the yellow‐rumped warbler, evidence suggests that mtDNA from the eastern, myrtle warbler, has introgressed across much of the range of the western form, the Audubon's warbler. Within the southwestern United States myrtle mtDNA comes into contact with another clade that occurs in the Mexican black‐fronted warbler. Both northern forms exhibit seasonal migration, whereas black‐fronted warblers are nonmigratory. We investigated the link between mitochondrial introgression, mitochondrial function, and migration using novel genetic, isotopic, biochemical, and phenotypic data obtained from populations in the transition zone. Isotopes suggest the zone is coincident with a shift in migration, with individuals in the south being resident and populations further north becoming increasingly more migratory. Mitochondrial respiration in flight muscles demonstrates that myrtle‐type individuals have a significantly greater acceptor control ratio of mitochondria, suggesting it may be more metabolically efficient. To our knowledge this is the first time this type of intraspecific variation in mitochondrial respiration has been measured in wild birds and we discuss how such mitochondrial adaptations may have facilitated introgression. 相似文献
55.
Radisic M Yang L Boublik J Cohen RJ Langer R Freed LE Vunjak-Novakovic G 《American journal of physiology. Heart and circulatory physiology》2004,286(2):H507-H516
We hypothesized that functional constructs with physiological cell densities can be engineered in vitro by mimicking convective-diffusive oxygen transport normally present in vivo. To test this hypothesis, we designed an in vitro culture system that maintains efficient oxygen supply to the cells at all times during cell seeding and construct cultivation and characterized in detail construct metabolism, structure, and function. Neonatal rat cardiomyocytes suspended in Matrigel were cultured on collagen sponges at a high initial density (1.35 x 10(8) cells/cm(3)) for 7 days with interstitial flow of medium; constructs cultured in orbitally mixed dishes, neonatal rat ventricles, and freshly isolated cardiomyocytes served as controls. Constructs were assessed at timed intervals with respect to cell number, distribution, viability, metabolic activity, cell cycle, presence of contractile proteins (sarcomeric alpha-actin, troponin I, and tropomyosin), and contractile function in response to electrical stimulation [excitation threshold (ET), maximum capture rate (MCR), response to a gap junctional blocker]. Interstitial flow of culture medium through the central 5-mm-diameter x 1.5-mm-thick region resulted in a physiological density of viable and differentiated, aerobically metabolizing cells, whereas dish culture resulted in constructs with only a 100- to 200-microm-thick surface layer containing viable and differentiated but anaerobically metabolizing cells around an acellular interior. Perfusion resulted in significantly higher numbers of live cells, higher cell viability, and significantly more cells in the S phase compared with dish-grown constructs. In response to electrical stimulation, perfused constructs contracted synchronously, had lower ETs, and recovered their baseline function levels of ET and MCR after treatment with a gap junctional blocker; dish-grown constructs exhibited arrhythmic contractile patterns and failed to recover their baseline MCR levels. 相似文献
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Ibrić S Jovanović M Djurić Z Parojcić J Petrović SD Solomun L Stupar B 《AAPS PharmSciTech》2003,4(1):62-70
The purpose of the present study was to model the effects of the concentration of Eudragit L 100 and compression pressure
as the most important process and formulation variables on the in vitro release profile of aspirin from matrix tables formulated
with Eudragit L 100 as matrix substance and to optimize the formulation by artificial neural network. As model formulations,
10 kinds of aspirin matrix tablets were prepared. The amount of Eudragit L 100 and the compression pressure were selected
as causal factors. In vitro dissolution time profiles at 4 different sampling times were chosen as responses. A set of release
parameters and causal factors were used as tutorial data for the generalized regression neural, network (GRNN) and analyzed
using a computer. Observed results of drug release studies indicate that drug release rates vary widely between investigated
formulations, with a range of 5 hours to more than 10 hours to complete dissolution. The GRNN model was optimized. The root
mean square value for the trained network was 1.12%, which indicated that the optimal GRNN model was reached. Applying the
generalized distance function method, the optimal tablet formulation predicted by GRNN was with 5% of Eudragit L 100 and tablet
hardness 60N. Calculated difference (f
1 2.465) and similarity (f
2 85.61) factors indicate that there is no difference between predicted and experimentally observed drug release profiles for
the optimal formulation. This work illustrates the potential for an artificial neural network, GRNN, to assist in development
of extended release dosage forms. 相似文献
58.
Influence of extremely low frequency electromagnetic field (ELF-EMF) on thyroid gland mast cells was investigated on male Mill Hill rats. Animals were exposed to EMF (50 Hz, 50 microT to 500 microT, 10 V/m) from 24 hours after birth, 7 hours/day, 5 days/week for three months when a part of animals (group I) was sacrificed, while the rest of them were subjected to recovery evaluation and sacrificed after one (group II), two (group II) and three (group IV) weeks following the exposure. Stereological analysis on toluidine blue-stained paraffin sections showed increased volume density of degranulated mast cells in all groups and, except in group III, and numerical density as well, implicating the sensitivity of thyroidal mast cells to power frequency EMFs. Since in our previous investigations, morphofunctional alterations of thyroid gland in rats exposed to ELF-EMF were found the contribution of released mast cell mediators to these changes could be presumed. 相似文献
59.
Milica Enoiu Régine Herber Robert Wennig Claude Marson Haline Bodaud Pierre Leroy Niculina Mitrea Gérard Siest Maria Wellman 《Archives of biochemistry and biophysics》2002,397(1):18-27
A major pathway for detoxification of the highly reactive lipid peroxidation product, 4-hydroxy-2,3-trans-nonenal (HNE) is through the conjugation with glutathione (GSH). We have studied the metabolism of GS-HNE conjugate by the enzyme gamma-glutamyltranspeptidase (GGT) using its purified form, as well as a GGT-overexpressing fibroblast cell line (V79 GGT). Using mass spectrometry analysis we identified for the first time cysteinylglycine-HNE (CysGly-HNE) as the GGT metabolite of GS-HNE. Furthermore, the GGT-dependent metabolism of GS-HNE in the V79 GGT cell line was associated with a considerable increase of cytotoxicity as compared to a control cell line which does not express GGT (V79 Cl). The cytotoxic effect was dose- and time-dependent (100% cellular death at 200 microM GS-HNE after 24 h incubation) in V79 GGT cells, whereas no decrease of viability was observed in V79 Cl cells. A similar cytotoxic effect was obtained when cells were incubated directly with CysGly-HNE, demonstrating that this GGT-dependent metabolite unlike GS-HNE, exhibits cytotoxic properties. 相似文献
60.
Heterologous production of the heterodimeric penicillin G amidase (PAC) from Providencia rettgeri was optimized in Saccharomyces cerevisiae. Several factors, including the effect of different growth and induction conditions, were identified to be critical for the enzyme overproduction and secretion. The PAC yield was significantly increased by more than 500-fold compared to that obtained in the native bacterium, and the recombinant enzyme was almost entirely secreted. Electrophoretic characterization of the secreted rPAC(Pr), which was purified over 20-fold by a combination of hydrophobic interaction and ion-exchange chromatography, demonstrated a microheterogeneity of the recombinant enzyme. The recombinant PAC(Pr) was further characterized in terms of specific activity, pH, and temperature profiles and kinetic parameters. The data presented here suggest that by overexpressing rPAC(Pr) in S.cerevisiae and purifying secreted enzyme from culture medium one can readily obtain a large amount of an alternative source of penicillin amidase with properties comparable to that of todays main industrial source of enzyme. 相似文献