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The exposure to extremely low frequency electromagnetic field (ELF-MF, frequencies less than 200-300 Hz) can alter the transcription and translation of genes, influence the cell proliferation rate and affect enzyme activities. Moreover, the hypothesis that ELF-MF increases free oxygen metabolites generation has been proposed. Since recent in vivo studies suggest that electric and magnetic fields are able to affect adipose cells metabolism. The aim of the study was to examine the effects of ELF-MF (frequency of basic impulse 180-195 Hz, induction 120 µT) on cell proliferation, antioxidative enzyme activities and malondialdehyde (MDA) concentration in 3T3-L1 preadipocyte cell culture. We found that ELF-MF application lasting 36 minutes daily failed to influence cell count after 24h and 48 h of incubation. After 24 h, in the ELF-MF treated group, manganese- and copper-zinc-containing superoxide dismutase (MnSOD and Cu/ZnSOD) isoenzymes media activities were decreased, catalase activity was increased, whereas there were no significant differences in glutathione peroxidase (GSH-Px) and glutathione reductase (GSSG-Rd) activities in comparison to the control. After 48 h of incubation, all enzyme activities were reduced, except for GSSG-Rd, in which no changes were noticed. MDA concentration at 24 h after incubation with the exposure to ELF-MF was significantly higher in comparison to the control, without ELF-MF. After 48 h of incubation, MDA levels were significantly lower in both groups with no differences between the groups without and with ELF-MF. We conclude that ELF-MF influences antioxidative enzyme activities and increases lipid peroxidation in 3T3-L1 preadipocyte cultures.
Transition from round budding cells to long hyphal forms and production of secreted aspartic proteases (Saps) are considered virulenceassociated factors of Candida albicans. Although plenty of data dealing with Saps involvement in the infection process have been published, Saps expression by the different pleomorphic forms as well as the capacity of C. albicans filaments to express Sap1-6 under serum influence are poorly investigated. In this study, we used immunofluorescence and immunoelectron microscopy for the detection of Sap1-6 isoenzymes in C. albicans pleomorphic cells (blastoconidia, germ tubes, pseudohyphae, true hyphae) grown in Sap-inductive human serum and Sap non-inductive medium – yeast extract-peptone-glucose (YEPD). Isoenzymes were below the detection level in all blastoconidial cells grown in YEPD for 18 h. Sap1-6 expression was hardly detected in C. albicans cells cultivated in serum for 20 min. Increasing level of Sap1-6 expression was observed when C. albicans was incubated for 2, 6 and 18 h in serum corresponding to the development of germ tubes, pseudohyphae and true hyphae. !e expression of Sap1-3 in pseudohyphae and true hyphae was more intensive compared to Sap4-6. !us, we could show that human serum induced hyphae formation and the expression of Sap1-6 were co-regulated.
Fungicidal properties of 4-(1,3,4-thiadiazol-2-yl)benzene-1,3-diols set under in vitro conditions against five phytopathogenic fungi have been evaluated. The substitution panel includes amino-, alkyl-, alkoxyl-, aryl- and heteroarylderivatives. The most active compound with the benzyl substituent exhibits fungistatic effects amounting to 90-100% with the concentration of 20 μg mL-1 against R. solani, similar to the standard fungicides. The derivatives with amine moiety generally display lower activity than other analogues. F. culmorum seems to be the most refractory fungus compared to studied compounds. The influence of substitution of C-5 at the constant fragment at C-2 of 1,3,4-thiadiazole ring on the antifungal effect is discussed. To explain differences in the activity the quantum-chemical calculations were made.
This study was planned to assess the antioxidant and free radical scavenging effect of D-carvone against L-NAME (Nω-nitro-L-arginine methyl ester hydrochloride) induced hypertension. Hypertension was encouraged in adult male albino rats of the Wistar strain, considering 180–230 g, by oral administration of the L-NAME (40 mg/kg/ body weight/day) in drinking water for 4 weeks. Rats were cured with D-carvone (5, 10 and 20 mg/kg body weight) for four weeks. A significant reduction in the levels of non-enzymatic antioxidants such as vitamin C, vitamin E and reduced glutathione (GSH), in plasma were perceived in L- NAME induced hypertensive rats. Moreover, in vitro free radical scavenging activity of ABTS+ and DPPH• radical scavenging possible of D-carvone was also quantified. Treatment with D-carvone (5, 10 and 20 mg/kg bw) carries back all the above parameters to near usual level, in which 20 mg/kg displayed the highest effect than that of other two doses. Further, D-carvone displays concentration dependent antioxidant potential. These results suggest that D-carvone acts as an antioxidant and free radical scavenging agent against L-NAME induced hypertension.
The examinations were conducted on hepatocvtes isolated by means of enzymatic method from the liver of three-month-old Wistar rats. The cells were incubated in medium with addition of theophylline and/or N-acetylcysteine. Significant changes in the activity of SOD, GPx, and GR in hepatocvtes incubated in the presence of the compounds in comparison with control cells demonstrated that theophylline and/or N-acetylcysteine disturb oxidative-reductive homeostasis of the cells. Changes in concentrations of ketone bodies, resulting in disturbances of acetoacetate to ß-hydroxybutyrate molar ratio, point to an unfavourable interference of theophylline into ketogenesis, which is equivalent with the disturbance of the balance between NAD⁺ and NADH+H⁺ in hepatocvtes. N-acetylcysteine simultaneously present with theophylline in incubation medium exerted a protective action on ketogenesis.
The noble gas xenon is an antagonist of the NMDA (N-methyl-D-aspartate)-type glutamate receptor which may account for the ideal anesthetic profile and potent neuroprotective properties demonstrated even at subanesthetic concentrations. Because lipid emulsions also promote NMDA antagonistic effects they may serve as ideal carriers for xenon. In this in vitro study, we investigated the efficacy of xenon dissolved in various lipid emulsions (Intralipid®, Lipofundin®, ClinOleic® and Abbolipid®) on NMDA-evoked currents in cultured cortical neurons. The NMDA receptor blocking property at a clinically relevant concentration seen in the lipid emulsions tested may contribute to the anesthetic, analgetic and neuroprotective effects of xenon administered by way of these lipid carriers. Abbolipid® may serve as the most acceptable carrier since the NMDA antagonistic effect of xenon was enhanced in combination with this emulsion.
Background. Use of plant extracts and phytochemicals with known antimicrobial properties may have great significance in therapeutic treatments. Objective. To assess the in vitro antimicrobial potential and also determine the minimum inhibitory concentration (MIC) of Citrus sinensis peel extracts with a view of searching a novel extract as a remedy for periodontal pathogens. Materials and Methods. Aqueous and ethanol (cold and hot) extracts prepared from peel of Citrus sinensis were screened for in vitro antimicrobial activity against Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia, using agar well diffusion method. The lowest concentration of every extract considered as the minimal inhibitory concentration (MIC) values were determined for both test organisms. Confidence level and level of significance were set at 95% and 5% respectively. Results. Prevotella intermedia and Porphyromonas gingivalis were resistant to aqueous extracts while Aggregatibacter actinomycetemcomitans was inhibited at very high cncentrations. Hot ethanolic extracts showed significantly higher zone of inhibition than cold ethanolic extract. Minimum inhibitory concentration of hot and cold ethanolic extracts of Citrus sinensis peel ranged between 12-15 mg/ml against all three periodontal pathogens. Conclusions. Both extracts were found sensitive and contain compounds with therapeutic potential. Nevertheless, clinical trials on the effect of these plants are essential before advocating large-scale therapy.
Melatonin, acting via MT1, MT2 and MT3 membrane receptors, influences central and peripheral regulatory mechanisms of energy homeostasis in mammals. In peripheral tissues, it evokes the pro-proliferative effect in a number of normal cells. Moreover, this hormone inhibits lipolysis in subcutaneous adipocytes in vitro and reduces free oxygen metabolites-induced damage acting directly, as a free radical scavenger, and indirectly, by stimulation of antioxidative enzyme activities. The aim of the study was to examine the effects of melatonin on cell proliferation, antioxidative enzyme activities and malondialdehyde (MDA) concentration in 3T3-L1 preadipocyte cell culture. We found that melatonin (10-3 and 10-6 M/L) stimulated cell proliferation in dose- and time-depending manner, and this effect was inhibited by a relatively selective MT2 receptor antagonist - luzindole (10-4 M/L). Melatonin, increased activities of manganese containing and copper-zinc containing superoxide dismutase (MnSOD and Cu/ZnSOD) isoenzymes, catalase, glutathione reductase and glutathione peroxidase after 24 h of incubation. In contrast, after 48 h of incubation, activities of all studied enzymes were lower than in the control group. There were no changes in MDA concentrations after 24 h of incubation, whereas, in melatonin-treated media, after 48 h of the experiment, MDA level was significantly decreased. Our results demonstrate that melatonin, acting via MT2 receptors, stimulates proliferation of 3T3-L1 preadipocytes and this action could be due to the enhancement in antioxidative enzyme activities and attenuation of lipid peroxidation by this indole.
The activity of picoxystrobin and its mixtures with standard fungicides against isolates of eyespot cereal disease agents was estimated in laboratory in vitro tests. The tested Ramulispora herpotrichoides and R. acuformis isolates differed in response to carbendazim. Picoxystrobin at concentration from 0.05 to 50 mg/L not totally inhibited the mycelium growth of tested pathogens on PDA medium. But carbendazim sensitive R. herpotrichoides isolates were a little more susceptible to strobilurin derivate than carbendazim resistant R. herpotrichoides isolate and R. acuformis strains. The effect of picoxystrobin at concentration 0.5 mg/L as partner in mixture with standard fungicide at concentration 0.1 mg/L (carbendazim, prochloraz or cyprodinil) was assessed as the additive. It was relatively most noticeably in tests with R. acuformis and picoxystrobin plus cyprodinil mixture that was for mixture recommended as tank-mix or as manufacture product.
Anti-proliferative activity was investigated of C18:2 9cis,11trans (conjugated linoleic acid – CLA) isomer isolated from sheep milk fat. The research was conducted on sheep milk fatty acids in natural composition (FA-1) containing 2.0% of the C18:2 9cis,11trans CLA isomer and preparation enriched with CLA, containing up to 9.2% of the CLA isomer (FA-2). The process of enrichment of FA-1 was carried out in two steps. Step I was to remove mid-chain-length saturated fatty acids, primarily C16,by forming adducts with urea (to obtain FA-U), while in step II the short-chain acids were removed by way of supercritical extraction with CO2. The final preparation obtained (FA-2) contained 9.2% of the C18:2 9cis,11trans isomer. A natural sheep milk fatty acid composition (FA-1), the CLA-enriched product (FA-2) and a commercial CLA preparation (CP) were tested for anti-proliferative activity against the cells of human cervical carcinoma (KB), and leukaemia (HL-60). The ID50 dose (resulting in a 50% inhibition of cell proliferation) of FA-2 was found lower than that of the CP preparation. The SRB test showed.
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