Authors:L. Stoica, D. Filip, Gh. Filip, A. Razvan, and R. Radulescu
A comparative study is presented on decontamination of the solutions containing226Ra(II), by applying coprecipitation of Ba(Ra)SO4 followed by flotation and selective adsorption on active carbon. The comparative study revealed the performances of separation
by coprecipitation-flotation and the possibility of applying the selective adsorption on active carbon. Both methods ensure
the decreasing of226Ra(II) concentration under the allowed limits, recommended by International Standards.
Authors:Simona Clichici, T. Mocan, A. Filip, A. Biris, S. Simon, D. Daicoviciu, N. Decea, A. Parvu, R. Moldovan, and A. Muresan
Single-walled carbon nanotubes (SWCNTs) have been proposed for various medical applications. However, their safety for human administration has not been yet fully demonstrated. In vitro studies have pointed oxidative stress as a mechanism involved in their cytotoxic effects. In the present study we have evaluated the capacity of DNA functionalized SWCNTs to induce oxidative stress in blood after intraperitoneal (ip) administration in rats. The presence of SWCNTs in blood was confirmed by Raman spectroscopy 30 minutes after their ip administration. Oxidative stress parameters (malondialdehyde — MDA, protein carbonyls — PC, antioxidant capacity measured as hydrogen donating capacity — HD, sulfhydryl groups — SH, glutathione — GSH and nitrites — NO) were assessed in blood at 3, 6, 24, respectively, and 48 hours after ip injection. MDA, PC and NO exhibited a significant increase at 3-6 hours interval from exposure, followed by a recovery trend. The levels of HD reached a bottom level at 6 hours after administration, while SH strongly decreased at 3 hours interval and increased slightly up to 48 hours without attending the initial values. GSH level recorded an increasing tendency at the 3rd hour, an incomplete recovery process at 24 hours followed by a secondary significant increase following a 48-hour interval. Significant inverse correlations were obtained between the PC and SH levels and between the NO and HD values. In conclusion, the ip administration of DNA functionalized SWCNT in rats results in oxidative stress generation in plasma, with a transient pattern of evolution.
Authors:M. Łaszcz, K. Trzcińska, K. Filip, A. Szyprowska, M. Mucha, and P. Krzeczyński
Differential scanning calorimetry and thermogravimetry techniques were successfully used for stability studies of capecitabine. Decreasing values of melting temperature, heat of fusion, and peak purity calculated from the Van’t Hoff equation indicated the gradual decomposition of capecitabine stored at 40 °C in 75% of relative humidity. The increase in mass loss connected with the water sorption was observed simultaneously. High performance liquid chromatography proved the results of thermoanalytical studies. Infrared spectroscopy (IR) appeared to have the lower sensitivity for the decomposition products detection.
Authors:Adriana Mureşan, C. Alb, S. Suciu, S. Clichici, A. Filip, C. Login, N. Decea, and T. Mocan
To estimate the effects of hydroethanolic red grapes seeds extract obtained from
Vitis vinifera, Burgund Mare
, Romania (BMR) on oxidant-antioxidant ballance, as compared to ascorbic acid, during pregnancy in rats. Thirty Wistar female rats were assigned to three groups (n=10) which were administered by gavage: Group I, 3 × 100 mg/kg body weight saline, Group II — BMR 3 × 30 mg gallic acid equivalents/kg body weight; Group III — vitamin C 3 × 100 mg/kg body weight on days 1, 7 and 14 of pregnancy. On day 21 blood samples were collected. Malon dyaldehyde, lipid peroxides, protein carbonyls, nitric oxide (as oxidative stress parameters) and hydrogen donor ability and total thiol groups (as antioxidant parameters) serum concentrations were measured. Vitamin C significantly enhanced the antioxidant capacity of plasma (hydrogen donor ability, p=0.0001; thiol groups, p=0.0001), as well as nitric oxide levels (p=0.001). The extract increased the plasma antioxidant capacity (hydrogen donor ability, p=0.001; thiol groups p=0.001) and did not elevate the nitric oxide plasma levels in pregnant rats.In conclusion, in the chosen dose, the red grapes seed extract enhanced the plasma antioxidant capacity and did not influence the nitric oxide levels in pregnant rats.
Authors:Diana Olteanu, A. Filip, A. Mureşan, A. Nagy, F. Tabaran, R. Moldovan, N. Decea, C. Catoi, and S. Clichici
Inflammation and oxidative stress are important pathways in the development of liver fibrosis following biliary obstruction.Aim: To evaluate the effects of low dose dexamethasone and chitosan, a natural compound with no side-effects, on liver damage caused by bile duct ligation in rats.Materials and methods: Fifty female Wistar rats, randomly and equally divided in 5 groups: I (SHAM) underwent only laparotomy, II (BDL) with bile duct ligation, III (DEX) 0.125 mg/kg dexamethasone i.m. daily, IV (CS) 1 mg/kg chitosan by gavage and group V (DEX+CS), both substances. After six days, the following parameters were assessed from liver homogenates: malondialdehyde (MDA), protein carbonyls (PC), reduced glutathione (GSH), total SH groupings, nitric oxide (NO), and from plasma: MDA, γ-glutamyltranspeptidase (GGT), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total bilirubin (TB). A histopathological examination was performed using some of the elements of the Knodell Histological Activity Index.Results: BDL significantly increases the levels of MDA, liver enzymes, and the necro-inflammatory score compared to the sham group and it decreases the antioxidant capacity. DEX protects against lipid peroxidation and improves the antioxidant capacity, but it is not able to protect the hepatocytes. Chitosan significantly decreases (p<0.05) the levels of MDA (0.07±0.01 vs 0.10±0.01 nmoles/mg protein BDL group, p=0.027) and also ALT, TB, GGT and reduces liver necrosis and inflammation (2.75±0.95 vs 1±0, p<0.05). Both CS and DEX reduce the level of NO significantly.Conclusion: BDL induces severe oxidative stress damage after six days already. Chitosan proved very efficient in protecting the hepatocytes against oxidative stress, a fact supported by the histological findings.
Authors:Simona Clichici, A. Filip, D. Daicoviciu, R. Ion, T. Mocan, C. Tatomir, L. Rogojan, D. Olteanu, and A. Muresan
Photodynamic therapy (PDT) is a promising therapy especially in skin cancer, using the systemic administration of a photosensitizer (PS), followed by the local irradiation of the tumor with visible light. The antitumor effects of PDT are determined especially by the generation of cytotoxic reactive oxygen species (ROS). The 5,10,15,20-tetrasulfophenyl-porphyrin (TSPP) is a synthetic photosensitizer, which proved its efficiency in in vitro studies. Our study evaluates the effects of PDT with TSPP upon the tumor levels of ROS and upon the metalloproteinases 2 (MMP2) activities on Wistar male rats bearing 256 Walker carcinosarcoma in correlation with the accumulation of PS in the tumor and with the intratumor histological alterations. The evaluations were performed dynamically, at 3 hours, 6 hours, 24 hours and 14 days after the PDT with TSPP. Our results emphasize that 24 hours after the PDT with TSPP, the ROS generation increases, as revealed by protein carbonyls and malondialdehyde levels and the antioxidant capacity (hydrogen donors, thiol groups) decreases in the tumor tissue. These parameters were correlated with the appearance of the histological disorders. The MMP-2 activity increases exponentially in the 24 hours — 14 days post PDT interval. PDT with TSPP offers, in vivo, consistent results regarding ROS generation, MMP2 activation and cytotoxic capacity.
Authors:Simona Clichici, C. Catoi, T. Mocan, A. Filip, C. Login, A. Nagy, D. Daicoviciu, N. Decea, C. Gherman, R. Moldovan, and Adriana Muresan
Oxidative stress is related to the liver fibrosis, anticipating the hepatic stellate cells’ (HSC) activation. Our aim was to correlate oxidative stress markers with the histological liver alterations in order to identify predictive, noninvasive parameters of fibrosis progression in the evolution of toxic hepatitis.CCl4 in sunflower oil was administered to rats intragastrically, twice a week. After 2, 3, 4 and 8 weeks of treatment, plasma levels of malondialdehyde (MDA), protein carbonyls (PC), hydrogen donor capacity (HD), sulfhydryl groups (SH), and glutathione (GSH) were measured and histological examination of the liver slides was performed. Dynamics of histological disorders was assessed by The Knodell score. Significant elevation of inflammation grade was obtained after the second week of the experiment only (p=0.001), while fibrosis started to become significant (p=0.001) after 1 month of CCl4 administration. Between plasma MDA and liver fibrosis development a good correlation was obtained (r=0.877, p=0.05). Correlation between PC dynamics and liver alterations was marginally significant for inflammation grade (r=0.756, p=0.138). HD evolution revealed a marginally inverse correlation with inflammation grade (r=−0.794, p=0.108). No correlations could be established for other parameters with either inflammation grade or fibrosis stage.Our study shows that MDA elevation offers the best prediction potential for fibrosis, while marginal prediction fiability could be attributed to high levels of plasma PC and low levels of HD.