We have exploited confocal Raman microspectroscopy to investigate the chemio-structural features ... more We have exploited confocal Raman microspectroscopy to investigate the chemio-structural features of human spermatozoa as wells as the biomolecular effects induced by the environmental pollutant lindane, a organochlorine pesticide. The results of this study show that Raman spectroscopy can provide important information about the structure of human spermatozoa and that any changes due to the presence of pesticides appear as anomalies in the Raman spectrum obtained from intact sperm. Our findings suggest lindane-induced alterations of membrane proteins in pesticide-treated spermatozoa. This study constitutes the first Raman spectroscopic study of human spermatozoa and suggests that an important advantage of this spectroscopy over other techniques is its ability to directly link changes in the biochemical structure to biological aspects of cell processes.
To evaluate the health effects deriving from the inhalation of air particulate matter a detailed ... more To evaluate the health effects deriving from the inhalation of air particulate matter a detailed characterization of the airborne particles is required. Many studies focused the attention on the particle dimensional range and in particular on the small size ( 40mg) was collected. A portion of the collected material was analyzed by ion mass spectrometry (ICP-MS, ICP-OES) and the bulk chemical composition evidenced the presence of heavy metals, in particular Cd, Cu, Cr, Fe, Pb and Zn. Consequently, in order to verify the potential mobility of heavy metals, a batch kinetic leaching test was executed, using a physiological solution (mimicking the pulmonary environment, pH 7.4, 37 °C) and various samples were collected from the solution at different times. Among the metals contained in the particulate, a leaching trend was observed principally for Pb, Cd and Cu, with Cd resulting as the most mobile heavy metal, whereas no Fe release was observed so far. Ongoing experiments will define th...
Most studies of brain iron relied on the effect of the iron on magnetic resonance (MR) relaxation... more Most studies of brain iron relied on the effect of the iron on magnetic resonance (MR) relaxation properties, such as R 2 * , and bulk tissue magnetic susceptibility, as measured by quantitative susceptibility mapping (QSM). The present study exploited the dependence of R 2 * and magnetic susceptibility on physical interactions at different length-scales to retrieve information about the tissue microenvironment, rather than the iron concentration. We introduce a method for the simultaneous analysis of brain tissue magnetic susceptibility and R 2 * that aims to isolate those biophysical mechanisms of R 2 *-contrast that are associated with the micro-and mesoscopic distribution of iron, referred to as the Iron Microstructure Coefficient (IMC). The present study hypothesized that changes in the deep gray matter (DGM) magnetic microenvironment associated with aging and pathological mechanisms of multiple sclerosis (MS), such as changes of the distribution and chemical form of the iron, manifest in quantifiable contributions to the IMC. To validate this hypothesis, we analyzed the voxel-based association between R 2 * and magnetic susceptibility in different DGM regions of 26 patients with multiple sclerosis and 33 age-and sexmatched normal controls. Values of the IMC varied significantly between anatomical regions, were
Background: Hyperhomocysteinemia (HHcy) causes increased oxidative stress and is an independent r... more Background: Hyperhomocysteinemia (HHcy) causes increased oxidative stress and is an independent risk factor for cardiovascular disease. Oxidative stress is now believed to be a major contributory factor in the development of non alcoholic fatty liver disease, the most common liver disorder worldwide. In this study, the changes which occur in homocysteine (Hcy) metabolism in high fat-diet induced non alcoholic fatty liver disease (NAFLD) in rats were investigated. Methods and results: After feeding rats a standard low fat diet (control) or a high fat diet (57% metabolisable energy as fat) for 18 weeks, the concentration of homocysteine in the plasma was significantly raised while that of cysteine was lowered in the high fat as compared to the control diet fed animals. The hepatic activities of cystathionine β-synthase (CBS) and cystathionine γ-lyase (CGS), the enzymes responsible for the breakdown of homocysteine to cysteine via the transsulphuration pathway in the liver, were also significantly reduced in the high fat-fed group. Conclusions: These results indicate that high fat diet-induced NAFLD in rats is associated with increased plasma Hcy levels caused by down-regulation of hepatic CBS and CGL activity. Thus, HHcy occurs at an early stage in high fat diet-induced NAFLD and is likely to contribute to the increased risk of cardiovascular disease associated with the condition.
We have exploited confocal Raman microspectroscopy to investigate the chemio-structural features ... more We have exploited confocal Raman microspectroscopy to investigate the chemio-structural features of human spermatozoa as wells as the biomolecular effects induced by the environmental pollutant lindane, a organochlorine pesticide. The results of this study show that Raman spectroscopy can provide important information about the structure of human spermatozoa and that any changes due to the presence of pesticides appear as anomalies in the Raman spectrum obtained from intact sperm. Our findings suggest lindane-induced alterations of membrane proteins in pesticide-treated spermatozoa. This study constitutes the first Raman spectroscopic study of human spermatozoa and suggests that an important advantage of this spectroscopy over other techniques is its ability to directly link changes in the biochemical structure to biological aspects of cell processes.
To evaluate the health effects deriving from the inhalation of air particulate matter a detailed ... more To evaluate the health effects deriving from the inhalation of air particulate matter a detailed characterization of the airborne particles is required. Many studies focused the attention on the particle dimensional range and in particular on the small size ( 40mg) was collected. A portion of the collected material was analyzed by ion mass spectrometry (ICP-MS, ICP-OES) and the bulk chemical composition evidenced the presence of heavy metals, in particular Cd, Cu, Cr, Fe, Pb and Zn. Consequently, in order to verify the potential mobility of heavy metals, a batch kinetic leaching test was executed, using a physiological solution (mimicking the pulmonary environment, pH 7.4, 37 °C) and various samples were collected from the solution at different times. Among the metals contained in the particulate, a leaching trend was observed principally for Pb, Cd and Cu, with Cd resulting as the most mobile heavy metal, whereas no Fe release was observed so far. Ongoing experiments will define th...
Most studies of brain iron relied on the effect of the iron on magnetic resonance (MR) relaxation... more Most studies of brain iron relied on the effect of the iron on magnetic resonance (MR) relaxation properties, such as R 2 * , and bulk tissue magnetic susceptibility, as measured by quantitative susceptibility mapping (QSM). The present study exploited the dependence of R 2 * and magnetic susceptibility on physical interactions at different length-scales to retrieve information about the tissue microenvironment, rather than the iron concentration. We introduce a method for the simultaneous analysis of brain tissue magnetic susceptibility and R 2 * that aims to isolate those biophysical mechanisms of R 2 *-contrast that are associated with the micro-and mesoscopic distribution of iron, referred to as the Iron Microstructure Coefficient (IMC). The present study hypothesized that changes in the deep gray matter (DGM) magnetic microenvironment associated with aging and pathological mechanisms of multiple sclerosis (MS), such as changes of the distribution and chemical form of the iron, manifest in quantifiable contributions to the IMC. To validate this hypothesis, we analyzed the voxel-based association between R 2 * and magnetic susceptibility in different DGM regions of 26 patients with multiple sclerosis and 33 age-and sexmatched normal controls. Values of the IMC varied significantly between anatomical regions, were
Background: Hyperhomocysteinemia (HHcy) causes increased oxidative stress and is an independent r... more Background: Hyperhomocysteinemia (HHcy) causes increased oxidative stress and is an independent risk factor for cardiovascular disease. Oxidative stress is now believed to be a major contributory factor in the development of non alcoholic fatty liver disease, the most common liver disorder worldwide. In this study, the changes which occur in homocysteine (Hcy) metabolism in high fat-diet induced non alcoholic fatty liver disease (NAFLD) in rats were investigated. Methods and results: After feeding rats a standard low fat diet (control) or a high fat diet (57% metabolisable energy as fat) for 18 weeks, the concentration of homocysteine in the plasma was significantly raised while that of cysteine was lowered in the high fat as compared to the control diet fed animals. The hepatic activities of cystathionine β-synthase (CBS) and cystathionine γ-lyase (CGS), the enzymes responsible for the breakdown of homocysteine to cysteine via the transsulphuration pathway in the liver, were also significantly reduced in the high fat-fed group. Conclusions: These results indicate that high fat diet-induced NAFLD in rats is associated with increased plasma Hcy levels caused by down-regulation of hepatic CBS and CGL activity. Thus, HHcy occurs at an early stage in high fat diet-induced NAFLD and is likely to contribute to the increased risk of cardiovascular disease associated with the condition.
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Papers by S. Palleschi