AIM:To investigate the effects of titanium dioxide (TiO2) nanoparticles (NPTiO 2 ) and microparticles (MPTiO 2 ) on the inflammatory response in the small intestine of mice. METHODS: Bl 57/6 male mice received distill...AIM:To investigate the effects of titanium dioxide (TiO2) nanoparticles (NPTiO 2 ) and microparticles (MPTiO 2 ) on the inflammatory response in the small intestine of mice. METHODS: Bl 57/6 male mice received distilled water suspensions containing TiO 2 (100 mg/kg body weight) as NPTiO 2 (66 nm), or MPTiO 2 (260 nm) by gavage for 10 d, once a day; the control group received only distilled water. At the end of the treatment the duodenum, jejunum and ileum were extracted for assessment of cytokines, inflammatory cells and titanium content. The cytokines interleukin (IL)-1b, IL-4, IL-6, IL-8, IL-10, IL-12, IL-13, IL-17, IL-23, tumor necrosis factor-α (TNF-α), intracellular interferon-γ (IFN-γ) and transforming growth factor-β (TGF-β) were evaluated by enzyme-linked immunosorbent assay in segments of jejunum and ileum (mucosa and underlying muscular tissue). CD4 + and CD8 + T cells, natural killer cells, and dendritic cells were evaluated in duodenum, jejunum and ileum samples fixed in 10% formalin by immuno-histochemistry. The titanium content was determined by inductively coupled plasma atomic emission spectrometry. RESULTS: We found increased levels of T CD4 + cells (cells/mm 2 ) in duodenum:NP 1240 ± 139.4, MP 1070 ± 154.7 vs 458 ± 50.39 (P < 0.01); jejunum:NP 908.4 ± 130.3, MP 813.8 ± 103.8 vs 526.6 ± 61.43 (P < 0.05); and ileum:NP 818.60 ± 123.0, MP 640.1 ± 32.75 vs 466.9 ± 22.4 (P < 0.05). In comparison to the control group, the groups receiving TiO 2 showed a statistically significant increase in the levels of the inflammatory cytokines IL-12, IL-4, IL-23, TNF-α, IFN-γ and TGF-β. The cytokine production was more pronounced in the ileum (mean ± SE):IL-12: NP 33.98 ± 11.76, MP 74.11 ± 25.65 vs 19.06 ± 3.92 (P < 0.05); IL-4: NP 17.36 ± 9.96, MP 22.94 ± 7.47 vs 2.19 ± 0.65 (P < 0.05); IL-23: NP 157.20 ± 75.80, MP 134.50 ± 38.31 vs 22.34 ± 5.81 (P < 0.05); TNFα: NP 3.71 ± 1.33, MP 5.44 ± 1.67 vs 0.99± 019 (P < 0.05); IFNγ: NP 15.85 ± 9.99, MP 34.08 ± 11.44 vs 2.81 ± 0.69 (P < 0.05); and TGF-β: NP 780.70 ± 318.50, MP 1409.00 ± 502.20 vs 205.50 ± 63.93 (P < 0.05). CONCLUSION:Our findings indicate that TiO2 particles induce a Th1-mediated inflammatory response in the small bowel in mice.展开更多
Formation of new blood vessels is paramount for tumour growth and metastatic dissemination and vascular endothelial growth factor (VEGF) is one of the key regulators of this process. The purpose of this study was to e...Formation of new blood vessels is paramount for tumour growth and metastatic dissemination and vascular endothelial growth factor (VEGF) is one of the key regulators of this process. The purpose of this study was to evaluate the immunohistochemical expression of VEGF in 23 splenic hemangiosarcomas and 7 splenic hemangiomas in dogs. Blood tests performed previous to splenectomy were analysed for correlation with tumour VEGF expression. Results showed significantly higher VEGF expression in hemangiosarcomas than hemangiomas and lower hematocrit values and red cell count in dogs affected with malignant neoplasia (P < 0.05). These findings suggest the presence of high VEGF levels may be related to the malignant vascular proliferation seen in hemangiosarcomas.展开更多
Globally,the area of land cultivated with genetically modified(GM)crops has increased a thousand-fold over the last two decades.Although this technology has become important for food production,the regulatory framewor...Globally,the area of land cultivated with genetically modified(GM)crops has increased a thousand-fold over the last two decades.Although this technology has become important for food production,the regulatory frameworks that underpin these outcomes are based on a list of requirements for a risk assessment that differ from country to country.In recent years,policymakers have had the opportunity to learn from the controversies over transgenics to create effective regulatory milestones for emerging technologies,allowing them to reach their potential for a more sustainable agriculture,ensuring food security.In Brazil,Law No.11.105 of 24 March 2005 established a framework with four main organizations responsible for risk assessment and management.However,most of new breeding technologies did not exist at that time and were not considered in this law.In2016,Normative Resolution No.16 of the National Biosafety Technical Commission(CTNBio)was established to address this gap based on the evaluation of the products obtained through these techniques(termed Innovative Precision Improvement Techniques in the resolution),in a case-by-case consultation system.Briefly,if the product is designated to be a GM,the developer will have to go through the biosafety requirements and will be approved only after CTNBio risk assessment.If the product is designated not to be GM(for the purposes of the legislation),then it can be registered using the existing procedures.Currently,152 GM products are commercially approved in Brazil.In 2018,CTNBio assessed the first consultation on commercial release of plants generated using the new breeding technologies and has subsequently approved six products.It is expected that many institutions would be able to participate in Brazilian and world markets,developing and introducing new biotechnological solutions and products through a more sustainable approach and without facing public disapproval,a common issue for GM crops.展开更多
基金Supported by The Fundao de Amparo à Pesquisa do Estado de So Paulo
文摘AIM:To investigate the effects of titanium dioxide (TiO2) nanoparticles (NPTiO 2 ) and microparticles (MPTiO 2 ) on the inflammatory response in the small intestine of mice. METHODS: Bl 57/6 male mice received distilled water suspensions containing TiO 2 (100 mg/kg body weight) as NPTiO 2 (66 nm), or MPTiO 2 (260 nm) by gavage for 10 d, once a day; the control group received only distilled water. At the end of the treatment the duodenum, jejunum and ileum were extracted for assessment of cytokines, inflammatory cells and titanium content. The cytokines interleukin (IL)-1b, IL-4, IL-6, IL-8, IL-10, IL-12, IL-13, IL-17, IL-23, tumor necrosis factor-α (TNF-α), intracellular interferon-γ (IFN-γ) and transforming growth factor-β (TGF-β) were evaluated by enzyme-linked immunosorbent assay in segments of jejunum and ileum (mucosa and underlying muscular tissue). CD4 + and CD8 + T cells, natural killer cells, and dendritic cells were evaluated in duodenum, jejunum and ileum samples fixed in 10% formalin by immuno-histochemistry. The titanium content was determined by inductively coupled plasma atomic emission spectrometry. RESULTS: We found increased levels of T CD4 + cells (cells/mm 2 ) in duodenum:NP 1240 ± 139.4, MP 1070 ± 154.7 vs 458 ± 50.39 (P < 0.01); jejunum:NP 908.4 ± 130.3, MP 813.8 ± 103.8 vs 526.6 ± 61.43 (P < 0.05); and ileum:NP 818.60 ± 123.0, MP 640.1 ± 32.75 vs 466.9 ± 22.4 (P < 0.05). In comparison to the control group, the groups receiving TiO 2 showed a statistically significant increase in the levels of the inflammatory cytokines IL-12, IL-4, IL-23, TNF-α, IFN-γ and TGF-β. The cytokine production was more pronounced in the ileum (mean ± SE):IL-12: NP 33.98 ± 11.76, MP 74.11 ± 25.65 vs 19.06 ± 3.92 (P < 0.05); IL-4: NP 17.36 ± 9.96, MP 22.94 ± 7.47 vs 2.19 ± 0.65 (P < 0.05); IL-23: NP 157.20 ± 75.80, MP 134.50 ± 38.31 vs 22.34 ± 5.81 (P < 0.05); TNFα: NP 3.71 ± 1.33, MP 5.44 ± 1.67 vs 0.99± 019 (P < 0.05); IFNγ: NP 15.85 ± 9.99, MP 34.08 ± 11.44 vs 2.81 ± 0.69 (P < 0.05); and TGF-β: NP 780.70 ± 318.50, MP 1409.00 ± 502.20 vs 205.50 ± 63.93 (P < 0.05). CONCLUSION:Our findings indicate that TiO2 particles induce a Th1-mediated inflammatory response in the small bowel in mice.
文摘Formation of new blood vessels is paramount for tumour growth and metastatic dissemination and vascular endothelial growth factor (VEGF) is one of the key regulators of this process. The purpose of this study was to evaluate the immunohistochemical expression of VEGF in 23 splenic hemangiosarcomas and 7 splenic hemangiomas in dogs. Blood tests performed previous to splenectomy were analysed for correlation with tumour VEGF expression. Results showed significantly higher VEGF expression in hemangiosarcomas than hemangiomas and lower hematocrit values and red cell count in dogs affected with malignant neoplasia (P < 0.05). These findings suggest the presence of high VEGF levels may be related to the malignant vascular proliferation seen in hemangiosarcomas.
文摘Globally,the area of land cultivated with genetically modified(GM)crops has increased a thousand-fold over the last two decades.Although this technology has become important for food production,the regulatory frameworks that underpin these outcomes are based on a list of requirements for a risk assessment that differ from country to country.In recent years,policymakers have had the opportunity to learn from the controversies over transgenics to create effective regulatory milestones for emerging technologies,allowing them to reach their potential for a more sustainable agriculture,ensuring food security.In Brazil,Law No.11.105 of 24 March 2005 established a framework with four main organizations responsible for risk assessment and management.However,most of new breeding technologies did not exist at that time and were not considered in this law.In2016,Normative Resolution No.16 of the National Biosafety Technical Commission(CTNBio)was established to address this gap based on the evaluation of the products obtained through these techniques(termed Innovative Precision Improvement Techniques in the resolution),in a case-by-case consultation system.Briefly,if the product is designated to be a GM,the developer will have to go through the biosafety requirements and will be approved only after CTNBio risk assessment.If the product is designated not to be GM(for the purposes of the legislation),then it can be registered using the existing procedures.Currently,152 GM products are commercially approved in Brazil.In 2018,CTNBio assessed the first consultation on commercial release of plants generated using the new breeding technologies and has subsequently approved six products.It is expected that many institutions would be able to participate in Brazilian and world markets,developing and introducing new biotechnological solutions and products through a more sustainable approach and without facing public disapproval,a common issue for GM crops.
