acid-phosphatase and titanium-dioxide

The ecotoxicology of nano-TiO2 has been extensively studied in recent years; however, few toxicological investigations have considered the photocatalytic properties of the substance, which can increase its toxicity to aquatic biota. The aim of this work was to evaluate the effects on fish exposed to different nano-TiO2 concentrations and illumination conditions. The interaction of these variables was investigated by observing the survival of the organisms, together with biomarkers of biochemical and genetic alterations. Fish (Piaractus mesopotamicus) were exposed for 96 h to 0, 1, 10, and 100 mg/L of nano-TiO2, under visible light, and visible light with ultraviolet (UV) light (22.47 J/cm(2)/h). The following biomarkers of oxidative stress were monitored in the liver: concentrations of lipid hydroperoxide and carbonylated protein, and specific activities of superoxide dismutase, catalase, and glutathione S-transferase. Other biomarkers of physiological function were also studied: the specific activities of acid phosphatase and Na,K-ATPase were analyzed in the liver and brain, respectively, and the concentration of metallothionein was measured in the gills. In addition, micronucleus and comet assays were performed with blood as genotoxic biomarkers. Nano-TiO2 caused no mortality under any of the conditions tested, but induced sublethal effects that were influenced by illumination condition. Under both illumination conditions tested, exposure to 100 mg/L showed an inhibition of acid phosphatase activity. Under visible light, there was an increase in metallothionein level in fish exposed to 1 mg/L of nano-TiO2. Under UV light, protein carbonylation was reduced in groups exposed to 1 and 10 mg/L, while nucleus alterations in erythrocytes were higher in fish exposed to 10 mg/L. As well as improving the understanding of nano-TiO2 toxicity, the findings demonstrated the importance of considering the experimental conditions in nanoecotoxicological tests. This work provides information for the development of protocols to study substances whose toxicity is affected by illumination conditions.

Topics: Acid Phosphatase; Animals; Brain; Characidae; Dose-Response Relationship, Drug; Ecotoxicology; Gills; Liver; Metal Nanoparticles; Metallothionein; Muscle, Skeletal; Oxidative Stress; Sodium-Potassium-Exchanging ATPase; Titanium; Ultraviolet Rays

Research projects focusing on biomaterials related factors; the bulk implant material, the macro-design of the implant and the microsurface roughness are routinely being conducted at our laboratories. In this study, we have investigated the bone tissue reactions to turned commercially pure (c.p.) titanium implants with various thicknesses of the oxide films after 6 weeks of insertion in rabbit bone. The control c.p. titanium implants had an oxide thickness of 17-200 nm while the test implants revealed an oxide thickness between 600 and 1000 nm. Routine histological investigations of the tissue reactions around the implants and enzyme histochemical detections of alkaline and acid phosphatase activities demonstrated similar findings around both the control and test implants. In general, the histomorphometrical parameters (bone to implant contact and newly formed bone) revealed significant quantitative differences between the control and test implants. The test implants demonstrated a greater bone response histomorphometrically than control implants and the osteoconductivity was more pronounced around the test implant surfaces. The parameters that differed between the implant surfaces, i.e. the oxide thickness, the pore size distribution, the porosity and the crystallinity of the surface oxides may represent factors that have an influence on the histomorphometrical results indicated by a stronger bone tissue response to the test implant surfaces, with an oxide thickness of more than 600 nm.

Topics: Acid Phosphatase; Alkaline Phosphatase; Animals; Biocompatible Materials; Bone and Bones; Female; Male; Microscopy, Electron, Scanning; Oxygen; Prostheses and Implants; Rabbits; Time Factors; Titanium; Tolonium Chloride

The purpose of this study was to assess the bioavailability and pulmonary toxicity of ZnCdS in rats. Groups of 30 male Fischer 344 rats each were anesthetized and dosed via intratracheal instillation with 5 mg of either ZnCdS, quartz (positive control), or titanium dioxide (TiO(2), negative control) suspended in 0.5 ml saline. A vehicle control group received 0.5 ml saline. Ten animals from each test group were sacrificed at 1 day, 1 wk, and 14 wk after dosing for bronchoalveolar lavage fluid (BALF) analysis and histopathology. The BALF was analyzed for alkaline phosphatase, acid phosphatase, lactate dehydrogenase (LDH), beta-glucuronidase (beta-glu), total protein, and cell counts. Two separate groups of 24 rats each were dosed as already described with either ZnCdS or saline. Eight rats from each group were sacrificed at 1 day, 1 wk, and 14 wk after dosing for determination of cadmium (Cd) and zinc (Zn) concentrations in the lung, liver, kidney, and blood. Results indicate that at 1 day after dosing, all enzyme activities (except acid phosphatase) and cell counts in BALF from the quartz and ZnCdS groups were significantly higher than in the TiO(2) and saline groups. At 7 days after dosing, high enzyme activity persisted in the quartz group, while the ZnCdS group showed only LDH and total protein levels significantly higher than the saline group. At 14 wk after dosing, LDH, total protein, beta-glu, and cell counts in the quartz group were significantly higher than all other groups. Histologic examination revealed interstitial inflammation and accumulation of foreign material in the lungs and mediastinal lymph nodes of quartz-, TiO(2)-, and ZnCdS-treated rats. Metal analyses in tissues showed profuse Cd and Zn concentrations in the lung 1 day after dosing, followed by a successive decline at 7 days and 14 wk after dosing. A very small, but statistically significant, amount of Cd and Zn was found in the kidneys at 14 wk after dosing. In conclusion, ZnCdS appears to cause temporary lung inflammation, is cleared slowly, and is poorly bioavailable.

Topics: Acid Phosphatase; Alkaline Phosphatase; Animals; Biological Availability; Bronchoalveolar Lavage Fluid; Cadmium; Cell Count; Feasibility Studies; Glucuronidase; Intubation, Intratracheal; L-Lactate Dehydrogenase; Lung; Pneumoconiosis; Quartz; Rats; Rats, Inbred F344; Sulfides; Titanium; Trachea; Zinc

To study the toxic effect of vanadium-titanium-magnetite (VTM) dust on alveolar macrophage (AM) and its hazardous extent.. Survival rates, morphology and function of AM were compared in rabbits exposed to dust of VTM, vanadium oxide, titanium dioxide and silica in various doses and length of time with in vitro cell culture and putamen membrane cover glass transmission electron microscopy, and changes in activities of lactic dehydrogenase (LDH) and acid phosphatase (ACP) in cell culture were measured.. Exposure to all the four kinds of dust could lead to decrease in survival rate of AM, increase in activities of LDH and ACP in the cell culture, and changes in their morphology and function to the extent dependent on the nature of dust.. Toxic effect of exposure to VTM dust was lower than that to vanadium oxide and silica, but higher than that to titanium dioxide, which had slight toxic effect.

Topics: Acid Phosphatase; Animals; Cells, Cultured; Dust; Iron; L-Lactate Dehydrogenase; Macrophages, Alveolar; Male; Rabbits; Titanium; Vanadium Compounds

The activities of the alkaline and the acid bone phosphatases as well as the concentrations of calcium and phosphorus were measured in the periimplantal tissue of the rat femur bone after implantation of the vitroceramic Ap 40, the metal oxide stabilized vitroceramics Ap 40 A and Ap 40 Z, as well titanium after 2, 10, and 15 weeks. The incorporation of the vitroceramic Ap 40 turns out like a primary bone fracture healing. The implants Ap 40 A and Ap 40 Z are a compromise with a higher stability and the osteogenesis induced effect is preserved, but is belated in contrast to Ap 40.

Topics: Acid Phosphatase; Alkaline Phosphatase; Aluminum; Aluminum Oxide; Animals; Bioprosthesis; Bone and Bones; Calcium; Ceramics; Femur; Phosphorus; Rats; Structure-Activity Relationship; Titanium; Zirconium

Lactate dehydrogenase (LDH) and lysosomal enzyme activity were measured in lung lavage fluid of guinea pigs exposed for 3 weeks to different concentrations of silica dust. Eight weeks and later after cessation of exposure, the amounts of N-acetyl-beta-D-glucosaminidase, cathepsin D, acid phosphatase, and LDH were increased. It is suggested that this increase indicates cell damage to alveolar macrophages, and that the enzyme changes are of relevance to determine the risk for pulmonary fibrosis caused by airborne substances.

Topics: Acetylglucosaminidase; Acid Phosphatase; Animals; Atmosphere Exposure Chambers; Cathepsin D; Cathepsins; Dust; Female; Guinea Pigs; L-Lactate Dehydrogenase; Lysosomes; Male; Pulmonary Alveoli; Silicon Dioxide; Titanium

Topics: Acid Phosphatase; Animals; Ascitic Fluid; Cell Count; Glucuronidase; Macrophages; Male; Mice; Phagocytosis; Pigments, Biological; Titanium

Topics: Acid Phosphatase; Animals; Ascitic Fluid; Cells, Cultured; Coloring Agents; Macrophages; Male; Mice; Titanium