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Dörnyei G, Monos E, Kaley G, Koller A: Regular exercise enhances blood pressure lowering effect of acetylcholine by increased contribution of nitric oxide. Acta Physiol. Hung. 87(2), 127-138 (2000) Regular exercise enhances blood

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Clemens, M. G.: Nitric oxide in liver injury. Hepatology, 1999, 30 , 1–5. Clemens M. G. Nitric oxide in liver injury Hepatology

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Sympathetic chain ganglia (SChG) neurons projecting to the descending colon of the pig were studied by means of retrograde tracing (Fast Blue, FB) and double-labelling immunofluorescence methods. FB was injected into the gut wall and after three weeks survival time the animals were transcardially perfused with paraformaldehyde and the bilateral sympathetic trunks were collected. The FBpositive neurons were localised only in the lumbar (L 1 –L 5 ) ganglia of the sympathetic trunk and appeared either as small (30–50 μm in diameter) round-shaped perikarya forming clusters localised in caudal-ventral area or, rarely, as bigger (50–80 μm) and dispersed solitary irregular perikarya. Immunohistochemical staining revealed the catecholaminergic (tyrosine hydroxylase-/dopamine β-hydroxylase-immunoreactive) character of the great majority of FB-positive neurons which preferentially co-expressed neuropeptide Y. In addition, none of the FB-positive perikarya was immunopositive to galanin, somatostatin, choline acetyltransferase, vasoactive intestinal peptide, pituitary adenylate cyclase-activating peptide, leu 5 -enkephalin, nitric oxide synthase, substance P and calcitonin-generelated peptide.

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This study assessed the preventive effects of arginine (ARG) and guanidinoacetic acid (GAA) on the incidence of pulmonary hypertension syndrome (PHS) in broiler chickens. Four isoenergetic and isonitrogenous diets were prepared, including: (i) the control, (ii) the control supplemented with 1 g/kg ARG, (iii) the control supplemented with 1 g/kg GAA, and (iv) the control supplemented with 1.5 g/kg GAA. These diets were fed to broilers (Ross 308) from day 1 to 42 post-hatch. Criteria evaluated in the experiment were growth performance, carcass characteristics, serum and blood variables, lead-II electrocardiogram, and ET-1 and iNOS gene expression in heart and lungs. Mortality from PHS was recorded daily. The results showed that ARG and GAA supplements improved the feed conversion ratio (FCR) compared to the control (P < 0.05). Supplementation of ARG and GAA significantly (P < 0.05) increased serum nitric oxide (NO) concentration. ARG and GAA supplementation significantly reduced the haematocrit value and the heterophil to lymphocyte ratio in the blood. A significant (P < 0.05) decline in S-wave amplitude of the lead-II electrocardiogram, right to total ventricular weight ratio (RV:TV) and ascites mortality was observed by supplementing ARG or 1.5 g/kg GAA. Addition of ARG and GAA supplements did not significantly change ET-1 and iNOS gene expression in the heart and lung relative to the control. In conclusion, GAA supplementation at 1.5 g/kg had a potential to improve growth performance and could prevent PHS.

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The present study evaluated the effects of doxorubicin (DOX) and deracoxib (DER), as single agents and in combination treatments, on antioxidant parameters in the canine mammary carcinoma cell line CMT-U27. The cells were exposed to DOX and DER for 24, 48 and 72 h. The viability and malondialdehyde (MDA), nitric oxide (NO), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSHPx) and total glutathione (GSH) activities of CMT-U27 cells were determined. The half inhibition concentration (IC50) of DOX was found to be ∼0.9 μM in the 72-h period. IC50 and 1/10 IC50 concentrations of DOX were combined with all concentrations of DER (50–1000 μM) in the combination experiments. The results showed increased oxidative status associated with significant decreases of CAT and GSH levels in CMT-U27 cells exposed to 10-μM and higher concentrations of DOX compared to control cells. In contrast, there were no significant changes in the groups tested with any of the concentrations of DER (50–1000 μM). In combination treatments, DER attenuated DOX-induced oxidative damage by modulating the enzymatic and non-enzymatic components in CMT-U27 cells. We suggest that the combination of DOX and DER can be beneficial in the treatment of cancer cells by increasing cellular responses to oxidative stress. In conclusion, the use of COX inhibitor in conjunction with a chemotherapeutic agent may provide a basis for new concepts of cancer treatment through systematic modulation of the antioxidant defence systems in mammary cancers of animals.

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Thioacetamide (TAA) is a potent hepatotoxicant in acute and chronic hepatic injury. The study examined the protective effect of sesame oil against TAA-induced hepatic injury in rats. Hepatic injury was induced by intraperitoneal injection of 100 mg/kg of TAA for 24 h. Triple doses of sesame oil (1, 2, or 4 mL/kg) was given orally 0, 6, and 12 h after TAA treatment. TAA significantly increased serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels. Sesame oil decreased serum AST and ALT levels and significantly inhibited hepatic lipid peroxidation and nitric oxide levels compared with TAA-alone group. Further, sesame oil significantly inhibited TAA-induced hepatic neutrophil activation marker myeloperoxidase activity. However, sesame oil did not affect hepatic tumor necrosis factor, IL-1β and IL-10 generation in TAA-treated group. In conclusion, sesame oil protects against TAA-induced hepatic injury and oxidative stress via the inhibition of neutrophil activation. However, inflammatory cytokines may not be involved in sesame-oil-associated hepatic protection against TAA in rats.

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The rising incidences of infections with multidrug-resistant (MDR) Gram-negative bacteria including Pseudomonas aeruginosa (PA) have gained increasing attention in medicine, but also in the general public and global health politics. The mechanisms underlying opportunistic pathogen—host interactions are unclear, however. To address this, we challenged secondary abiotic IL10−/− mice deficient for Toll-like receptor-4 (TLR4−/− × IL10−/−), the main receptor of the Gram-negative cell wall constituent lipopolysaccharide, with a clinical MDR PA isolate. Despite higher intestinal colonization densities, apoptotic colonic epithelial cell numbers were lower in TLR4−/− × IL10−/− mice as compared to IL10−/− controls at day 14 postinfection (p.i.), whereas proliferating/regenerating cells had increased in the latter only. Furthermore, PA-colonized TLR4−/− × IL10−/− mice displayed less distinct innate and adaptive immune cell responses in the colon as compared to IL10−/− counterparts that were accompanied by lower nitric oxide concentrations in mesenteric lymph nodes in the former at day 14 p.i. Conversely, splenic NO levels were higher in both naive and PA-colonized TLR4-deficient IL10−/− mice versus IL10−/− controls. Remarkably, intestinal MDR PA was able to translocate to extra-intestinal including systemic compartments of TLR4−/− × IL10−/− mice only. Hence, MDR PA-induced intestinal and systemic immune responses observed in secondary abiotic IL10−/− mice are TLR4-dependent.

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Abstract  

The hyphenated thermal analysis-mass spectrometry technique (TA-MS) was applied for the investigation of the thermal behavior of reference and aged parchment samples. The kinetic parameters of the process were calculated independently from all recorded TA and MS signals. The kinetic analysis showed the distinct dependence of the activation energy on the reaction progress. Such behavior is characteristic for the multistage mechanism of the reaction. The comparison of the kinetic parameters calculated from the different signals i.e. TG, DSC, MS for H2O, NO and CO2, however, indicated that they were differently dependent on the aging of the sample. For the parchment samples, the aging almost does not change the kinetics of the decomposition calculated from the DSC data: the influence of aging seems to be too negligible to be detected by these techniques. On the other hand, the much more sensitive mass spectrometric technique applied to the kinetic analysis allowed monitoring of visible changes in the thermal behavior of the parchment samples due to the aging process. The influence of aging was especially visible when the MS signals of water and nitric oxide were applied for the determination of the kinetic parameters. The applied method of the kinetic analysis allowed also the prediction of the thermal behaviour of reference and aged parchment samples under isothermal and modulated temperature conditions. Presented results have confirmed the usefulness of thermoanalytical methods for investigating behaviour of such complicated systems as leather or parchment.

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Thermal decomposition of uranyl nitrate hexahydrate

A thermal analysis—mass spectrometry study

Journal of Thermal Analysis and Calorimetry
Authors: K. Rajagopalan, P. Ravindran, and T. Radhakrishnan

Abstract  

TG-DTA-EGA studies have shown that anhydrous uranyl nitrate cannot be obtained by thermal decomposition of uranyl nitrate hexahydrate. Hydrolysis and polymerization of the salt during dehydration resulted in hydroxynitrates which decomposed in multiple steps with the evolution of oxides of nitrogen and water. The extent of hydrolysis dependend on the sample size, heating rate and nature of sample containment. Large samples on decomposition at relatively high heating rates showed evolution of nitric oxide even above 500°C. Infrared studies on the residues prepared at various temperatures supported the conclusions.

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Objective

In this study, we investigated the possible effect of Δ9-tetrahydrocannabinol (THC), a peroxisome proliferator-activated receptor gamma (PPARγ) agonist, on metabolic control and vascular complications of diabetes in streptozotocin/nicotinamide (STZ/NIC) induced type 2 diabetes mellitus.

Material and methods

Type 2 diabetes was induced with 65 mg/kg STZ, 15 minute later 85 mg/kg NIC was given intraperitoneally (i.p.) to rats. Three days after diabetes induction, THC (3 mg/kg/day, i.p.) was given for 7 days to diabetic rats. Body weight and plasma glucose levels of rats were measured in all groups before and at the end of 3 weeks after diabetes induction. Acetylcholine (Ach) and sodium nitroprusside (SNP) potency and maximum relaxant effects were calculated on aortic rings pre-contracted with noradrenaline (NA).

Results

At the end of 3 weeks, blood glucose levels of diabetic group significantly increased in comparison with the control group. Increased plasma glucose levels were significantly decreased by the treatment of THC. Ach induced relaxation was impaired whereas endothelium-independent relaxation to SNP was unaffected on isolated diabetic rat aorta. THC treatment enhanced Ach induced relaxation on diabetic rat aortas.

Discussion

These results suggested that THC improved endothelium-dependent relaxation in STZ/NIC induced diabetic rat aorta and that these effects were mediated at least in part, by control of hyperglycemia and enhanced endothelial nitric oxide bioavailability.

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