Plastics such as polyvinyl chlorides （PVC） are widely used in many indoor constructed environments; however, their unbound chemicals, such as di-（2-ethylhexyl） phthalates （DEHP）, can leach into the surrounding e...Plastics such as polyvinyl chlorides （PVC） are widely used in many indoor constructed environments; however, their unbound chemicals, such as di-（2-ethylhexyl） phthalates （DEHP）, can leach into the surrounding environment. This study focused on DEHP＇s effect on the central nervous system by determining the precise DEHP content in mice brain tissue after exposure to the chemical, to evaluate the specific exposure range. Primary neuronal-astrocyte co-culture systems were used as in vitro models for chemical hazard identification of DEHP. Oxidative stress was hypothesized as a probable mechanism involved, and therefore the total reactive oxygen species （ROS） concentration was determined as a biomarker of oxidative stress. In addition, NeuriteTracer, a neurite tracing plugin with ImageJ, was used to develop an assay for neurotoxicity to provide quantitative measurements of neurological parameters, such as neuronal number, neuron count and neurite length, all of which could indicate neurotoxic effects. The results showed that with 1 nmol/L DEHP exposure, there was a significant increase in ROS concentrations, indicating that the neuronal-astrocyte cultures were injured due to exposure to DEHP. In response, astrocyte proliferation （gliosis） was initiated, serving as a mechanism to maintain a homeostatic environment for neurons and protect neurons from toxic chemicals. There is a need to assess the cumulative effects of DEHP in animals to evaluate the possible uotake and effects on the human neuronal system from exoosure to DEHP in the indoor environment.展开更多
Objectives To determine the relative densities of the GABAergic subpopulation defined by calcium-binding proteins and to further study the importance of changes in GABAergic interneurons on neuropathology in the hippo...Objectives To determine the relative densities of the GABAergic subpopulation defined by calcium-binding proteins and to further study the importance of changes in GABAergic interneurons on neuropathology in the hippocampus in schizophrenia cases. Methods The relative densities and neuronal body size of cells immunoreactive for the calcium-binding proteins parvalbumin and calretinin as well as the area size of the hippocampal sub-fields were determined from the hippocampal tissue sections taken from schizophrenic patients and well-matched control subjects (15 per group). Results No significant difference in the density of calretinin-immunoreactive neurons and the neuronal body size of calretinin-positive neurons was found between subject groups. Relative to normal controls, schizophrenic patients showed a significant and profound deficit in the relative densities of parvalbumin-immunoreactive neurons in all hippocampal sub-fields. These reductions were more apparent in male schizophrenic patients and were unrelated to antipsychotic drug treatment, age or duration of illness. Conclusion The findings provide further evidence to support a profound and selective abnormality of a sub-population of GABAergic neurons in the hippocampus in schizophrenia cases, and are consistent with the etiological hypothesis of the neurodevelopment of schizophrenia.展开更多
基金supported by the Key Project of National Natural Science Foundation of China(No.51136002)China Key Technologies R&D Program(No.2012BAJ02B03)
文摘Plastics such as polyvinyl chlorides （PVC） are widely used in many indoor constructed environments; however, their unbound chemicals, such as di-（2-ethylhexyl） phthalates （DEHP）, can leach into the surrounding environment. This study focused on DEHP＇s effect on the central nervous system by determining the precise DEHP content in mice brain tissue after exposure to the chemical, to evaluate the specific exposure range. Primary neuronal-astrocyte co-culture systems were used as in vitro models for chemical hazard identification of DEHP. Oxidative stress was hypothesized as a probable mechanism involved, and therefore the total reactive oxygen species （ROS） concentration was determined as a biomarker of oxidative stress. In addition, NeuriteTracer, a neurite tracing plugin with ImageJ, was used to develop an assay for neurotoxicity to provide quantitative measurements of neurological parameters, such as neuronal number, neuron count and neurite length, all of which could indicate neurotoxic effects. The results showed that with 1 nmol/L DEHP exposure, there was a significant increase in ROS concentrations, indicating that the neuronal-astrocyte cultures were injured due to exposure to DEHP. In response, astrocyte proliferation （gliosis） was initiated, serving as a mechanism to maintain a homeostatic environment for neurons and protect neurons from toxic chemicals. There is a need to assess the cumulative effects of DEHP in animals to evaluate the possible uotake and effects on the human neuronal system from exoosure to DEHP in the indoor environment.
文摘Objectives To determine the relative densities of the GABAergic subpopulation defined by calcium-binding proteins and to further study the importance of changes in GABAergic interneurons on neuropathology in the hippocampus in schizophrenia cases. Methods The relative densities and neuronal body size of cells immunoreactive for the calcium-binding proteins parvalbumin and calretinin as well as the area size of the hippocampal sub-fields were determined from the hippocampal tissue sections taken from schizophrenic patients and well-matched control subjects (15 per group). Results No significant difference in the density of calretinin-immunoreactive neurons and the neuronal body size of calretinin-positive neurons was found between subject groups. Relative to normal controls, schizophrenic patients showed a significant and profound deficit in the relative densities of parvalbumin-immunoreactive neurons in all hippocampal sub-fields. These reductions were more apparent in male schizophrenic patients and were unrelated to antipsychotic drug treatment, age or duration of illness. Conclusion The findings provide further evidence to support a profound and selective abnormality of a sub-population of GABAergic neurons in the hippocampus in schizophrenia cases, and are consistent with the etiological hypothesis of the neurodevelopment of schizophrenia.
