Ultrastructural features of supraspinal muscles in rabbits after long-term transcutaneous lateral electrical surface stimulation (LESS)

Lateral electrical surface stimulation is one of methods used in the therapy of the progressive form of idiopathic scoliosis (IS) in children and youth. However, there are data suggesting that this method may lead to serious adverse side effects, when used for a too long period of time per day. To clarify this issue, the present study was aimed at disclosing possible changes in the ultrastructural appearance of rabbit supraspinal muscles undergoing long-term stimulation (9 h per day, 3 months), an animal model successfully used to mimic the situation in humans. In comparison to the control animals, muscles of "overstimulated" rabbits exhibited clear signs of microscopical lesions, including depletion and disintegration of myofilaments, proliferation, dilatation and, sometimes, swelling of sarcoplasmic reticulum and/or mitochondria, as well as signs of destruction of the Z line. The above-mentioned abnormalities, especially the signs of degenerative processes associated with the Z line and the observed microlesions strongly suggest that the failure of the long-term LESS therapy of the IS may be attributable to these ultrastructural lesions

Nanotitanium dioxide toxicity in mouse lung is reduced in sanding dust from paint

<p>Abstract</p> <p>Background</p> <p>Little is known of how the toxicity of nanoparticles is affected by the incorporation in complex matrices. We compared the toxic effects of the titanium dioxide nanoparticle UV-Titan L181 (NanoTiO₂), pure or embedded in a paint matrix. We also compared the effects of the same paint with and without NanoTiO₂.</p> <p>Methods</p> <p>Mice received a single intratracheal instillation of 18, 54 and 162 μg of NanoTiO₂or 54, 162 and 486 μg of the sanding dust from paint with and without NanoTiO₂. DNA damage in broncheoalveolar lavage cells and liver, lung inflammation and liver histology were evaluated 1, 3 and 28 days after intratracheal instillation. Printex 90 was included as positive control.</p> <p>Results</p> <p>There was no additive effect of adding NanoTiO₂to paints: Therefore the toxicity of NanoTiO₂was reduced by inclusion into a paint matrix. NanoTiO₂induced inflammation in mice with severity similar to Printex 90. The inflammatory response of NanoTiO₂and Printex 90 correlated with the instilled surface area. None of the materials, except of Printex 90, induced DNA damage in lung lining fluid cells. The highest dose of NanoTiO₂caused DNA damage in hepatic tissue 1 day after intratracheal instillation. Exposure of mice to the dust from paints with and without TiO₂was not associated with hepatic histopathological changes. Exposure to NanoTiO₂or to Printex 90 caused slight histopathological changes in the liver in some of the mice at different time points.</p> <p>Conclusions</p> <p>Pulmonary inflammation and DNA damage and hepatic histopathology were not changed in mice instilled with sanding dust from NanoTiO₂paint compared to paint without NanoTiO₂. However, pure NanoTiO₂caused greater inflammation than NanoTiO₂embedded in the paint matrix.</p

Acute and subacute pulmonary toxicity and mortality in mice after intratracheal instillation of ZnO nanoparticles in three laboratories

Inhalation is the main pathway of ZnO exposure in the occupational environment but only few studies have addressed toxic effects after pulmonary exposure to ZnO nanoparticles (NP). Here we present results from three studies of pulmonary exposure and toxicity of ZnO NP in mice. The studies were prematurely terminated because interim results unexpectedly showed severe pulmonary toxicity. High bolus doses of ZnO NP (25 up to 100μg; ≥1.4mg/kg) were clearly associated with a dose dependent mortality in the mice. Lower doses (≥6μg; ≥0.3mg/kg) elicited acute toxicity in terms of reduced weight gain, desquamation of epithelial cells with concomitantly increased barrier permeability of the alveolar/blood as well as DNA damage. Oxidative stress was shown via a strong increase in lipid peroxidation and reduced glutathione in the pulmonary tissue. Two months post-exposure revealed no obvious toxicity for 12.5 and 25μg on a range of parameters. However, mice that survived a high dose (50μg; 2.7mg/kg) had an increased pulmonary collagen accumulation (fibrosis) at a similar level as a high bolus dose of crystalline silica. The recovery from these toxicological effects appeared dose-dependent. The results indicate that alveolar deposition of ZnO NP may cause significant adverse health effects

Epoxy composite dusts with and without carbon nanotubes cause similar pulmonary responses, but differences in liver histology in mice following pulmonary deposition

Inorganic chemical composition given as elemental weight% measured by standardless WDXRF. The three epoxy materials were measured as solid disks (4 cm in diameter, 1 cm high). For comparison, the results for CNT powder, previously published in [25], were added to the figure. Displayed axis 99.7 – 100 %. (PPTX 71 kb

Changes in cholesterol homeostasis and acute phase response link pulmonary exposure to multi-walled carbon nanotubes to risk of cardiovascular disease

AbstractAdverse lung effects following pulmonary exposure to multi-walled carbon nanotubes (MWCNTs) are well documented in rodents. However, systemic effects are less understood. Epidemiological studies have shown increased cardiovascular disease risk after pulmonary exposure to airborne particles, which has led to concerns that inhalation exposure to MWCNTs might pose similar risks.We analyzed parameters related to cardiovascular disease, including plasma acute phase response (APR) proteins and plasma lipids, in female C57BL/6 mice exposed to a single intratracheal instillation of 0, 18, 54 or 162μg/mouse of small, entangled (CNTSmall, 0.8±0.1μm long) or large, thick MWCNTs (CNTLarge, 4±0.4μm long). Liver tissues and plasma were harvested 1, 3 and 28days post-exposure. In addition, global hepatic gene expression, hepatic cholesterol content and liver histology were used to assess hepatic effects.The two MWCNTs induced similar systemic responses despite their different physicochemical properties. APR proteins SAA3 and haptoglobin, plasma total cholesterol and low-density/very low-density lipoprotein were significantly increased following exposure to either MWCNTs. Plasma SAA3 levels correlated strongly with pulmonary Saa3 levels. Analysis of global gene expression revealed perturbation of the same biological processes and pathways in liver, including the HMG-CoA reductase pathway. Both MWCNTs induced similar histological hepatic changes, with a tendency towards greater response following CNTLarge exposure.Overall, we show that pulmonary exposure to two different MWCNTs induces similar systemic and hepatic responses, including changes in plasma APR, lipid composition, hepatic gene expression and liver morphology. The results link pulmonary exposure to MWCNTs with risk of cardiovascular disease

Effect of maternal selenium supplementation on pregnancy in humans and livestock Wpływ podawania suplementu selenu matce na ciążę u ludzi i zwierząt hodowlanych

Following publications underlining the potential use of selenium (Se) in reducing the risk of prostate, skin, colorectal, liver, mammary and lung cancer, awareness of the importance of Se to human health has markedly increased. Moreover, Se status has been inversely associated with other health problems, such as impaired immune function, arthropathy and cardiomyopathy. The most important and well-known Se functions are represented by cell protection against oxidative stress and regulation of thyroid hormone metabolism. Recently, ongoing studies have focused on the relationship between Se intake and fertility and reproductive pathology, as demonstrated by the finding of low Se levels in blood and placenta of women suffering pre-eclampsia and intrauterine growth retardation. Similar problems have also been investigated in livestock and, since the concentration of Se in different soils and different geographical regions varies, addition of this element to animal feed is often required to prevent Se-deficiency diseases in production animal systems. Furthermore, Se supplementation in cattle and ewes is associated with increased embryo production, higher fetal mass and reduced incidence of retained placenta. However, the beneficial effects of supranutrional diet - above European Commission and Food and Drug Administration recommendations (0.5 and 0.3 mg kg dm, respectively), but below the maximum tolerable level established by the National Research Council (5 mg kg dm) - are affected by other environmental, nutritional and management factors (source of Se, time and length of the treatment, presence of interfering elements, diet feeding pattern). The relationship between Se supplementation and the risk of reproductive diseases are complex but recent developments represent promising results in order to refine dietary recommendations for both humans and livestock and develop effective health strategies