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Jakob Korf - One of the best experts on this subject based on the ideXlab platform.
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induction of glial fibrillary acidic protein immunoreactivity in the rat dentate gyrus after adrenalectomy comparison with neurodegenerative changes using Silver Impregnation
Hippocampus, 1994Co-Authors: Hj Krugers, Folkert Postema, Rikje M Medema, Jakob KorfAbstract:In the present study we performed a light microscopic anatomical comparison of adrenalectomy (ADX)-induced neurodegeneration using Silver Impregnation and reaction of astroglial cells using GFAP immunocytochemistry in the hippocampus of the rat. Three survival times following ADX were studied: 24 hours, 3 days, and 3 weeks. Twenty-four hours following ADX we found no degenerative changes or altered GFAP immunostaining. Three days after adrenalectomy, argyrophilic somata appeared in the granular cell layer of the dentate gyrus. Argyrophilic dendrites were seen in the molecular layer of the dentate gyrus and neuritic argyrophilia were seen in the mossy fiber layer. Induction of GFAP immunoreactivity occurred simultaneously with degeneration. Increased GFAP immunoreactivity could be observed 3 days after adrenalectomy in the molecular layer of the dentate gyrus, granular cell layer, sub and supragranular cell layer, and mossy fiber layer. Size and shape of astroglial cells were changed, and their processes in the molecular layer changed from unidirectional to randomly organized. Degeneration and astroglial reaction were more pronounced 3 weeks after adrenalectomy and both were prevented by adding corticosterone to the drinking solution. Animals that did not show degenerative changes showed no increased GFAP immunoreactivity, while both effects were confined to the dentate gyrus and mossy fiber zone. These results show that there is a close relationship between the induction of GFAP immunoreactivity in the hippocampus of the rat and neuronal degeneration in the dentate gyrus following ADX, both in time and space.
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Time course and distribution of neuronal degeneration in the dentate gyrus of rat after adrenalectomy: a Silver Impregnation study.
Hippocampus, 1992Co-Authors: Dick Jaarsma, Folkert Postema, Jakob KorfAbstract:Recently, Sloviter et al. reported that adrenalectomy (ADX) of young adult rats after 3 months led to a selective loss of granule neurons in the dentate gyrus (DG) and that this loss could be prevented by low doses of corticosterone. In the present study, the ADX-induced neuronal degeneration was investigated in Wistar rats, using a Silver Impregnation method for degenerating neurons. To examine the time course and distribution of the ADX-induced degeneration, young adult male rats were allowed to survive 2, 3, and 5 days and 1, 2, and 3 weeks after ADX. Argyrophilic neurons were present in the dentate granule cell layer on the second day following ADX. Three days after ADX, the number of argyrophilic granule neurons was much more abundant, and it increased gradually with longer post-ADX survival times. Argyrophilia was specifically confined to dentate granule cells and was accompanied by the occurrence of pyknotic nuclei as observed in adjacent cresyl violet-stained sections. There were significant differences between individual rats in quantity of argyrophilia. About one fifth of the ADX rats showed sporadic or no argyrophilia, in spite of plasma corticosterone levels below the detection limit (10 ng/mL). Sham-operated rats and ADX rats receiving corticosterone (10 mg/L) or dexamethasone (15 mg/L) in their drinking water did not display any argyrophilic neurons in the dentate gyrus. The distribution of the argyrophilia within the DG was highly characteristic with the highest number of degenerating cells in the hidden blade of the middle and the temporal thirds of the DG.(ABSTRACT TRUNCATED AT 250 WORDS)
Hamid Reza Taghiyari - One of the best experts on this subject based on the ideXlab platform.
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effects of nano Silver Impregnation on brittleness physical and mechanical properties of heat treated hardwoods
Wood Science and Technology, 2013Co-Authors: Hamid Reza Taghiyari, Aliakbar Enayati, Hadi GholamiyanAbstract:The present study investigates the effect of heat treatment of untreated and nano-Silver-impregnated Populus nigra, Populus deltoides and Fagus orientalis on the physical and mechanical properties. Specimens were impregnated with a 200-ppm aqueous Silver nanoparticles suspension. Heat treatment was carried out at temperatures of 135 ± 3 °C and 185 ± 3 °C. Nano-Silver Impregnation aggravated the effects of heat treatment. Although significant in some cases, nano-Silver Impregnation did not seem to have great effect on physical properties. It may be concluded that although NS Impregnation aggravated the effects of heat treatment on solid woods, other factors may also be involved such as the species and density of the wood.
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effects of nano Silver Impregnation on some mechanical properties of ice blasted wood specimens
Journal of Tropical Forest Science, 2012Co-Authors: Hamid Reza Taghiyari, G Rassam, Y L Sani, A KarimiAbstract:TAGH1YARIHR, RASSAM G, LOTH NEJAD SANIY & KARIMI A. 2012. Effects of nano-Silver Impregnation on some mechanical properties of ice-blasted wood specimens. Ice blasting (frozen C02, -78.5 °C) is one of the modern methods of cleaning for industrial purposes. Effects of ice blasting were studied on untreated solid wood as well as 200 ppm nano-Silver impregnated wood of Populus nigra (poplar) and Fagus orientalis (beech). Modulus of rupture (MOR), modulus of elasticity (MOE) and compression strength parallel to the grain were measured. Ice blasting decreased MOR by 31.5 and 6% in poplar and beech respectively. However, when specimens were impregnated with nano-Silver, MOR would only decrease by 4.8% in beech and increase by 1.7% in poplar. Ice blasting decreased MOE and compression strength parallel to the grain by 62.5 and 2.5% respectively in poplar, and 8.6 and 4.4% in beech. The lower the density of a wood the more mechanical properties would decrease in untreated wood as a result of ice blasting. On the other hand, nano-Silver Impregnation decreased the amount of losses in MOR, MOE and compression strength parallel to the grain. Heat conductivity of nano-Silver particles transferred the cold accumulated on the surface layers of specimens. Consequently, mechanical properties would be improved by preventing the formation of microscopic fissures and surface checks.
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study on the effect of nano Silver Impregnation on mechanical properties of heat treated populus nigra
Wood Science and Technology, 2011Co-Authors: Hamid Reza TaghiyariAbstract:The present study is aimed at investigating the effect of heat treatment of nano-Silver-impregnated Populus nigra on weight loss, modulus of rupture (MOR), modulus of elasticity (MOE), and compression parallel to grain. Specimens were impregnated with 200 PPM water-based solution of nano-Silver particles at 2.5 bar in a pressure vessel. For heat treatment, both nano-Silver-impregnated and simple specimens were kept for 24 h at 45C and then further for 24 h at 145C and finally for 4 h at 185C. MOR decreased from 529 to 461 kg/cm 2 in heat-treated specimens; MOE and compression parallel to grain were though improved. Also, comparison between heat-treated and nano-Silver-impregnated heat-treated speci- mens showed that there was a decrease in MOR and MOE in nano-Silver-impreg- nated heat-treated specimens. This shows that nano-Silver Impregnation facilitates transfer of heat in wood and it may increase the process of degradation and pyrolysis of wood structures in deeper parts of specimens.
Kiminori Isaki - One of the best experts on this subject based on the ideXlab platform.
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Non-familial olivopontocerebellar atrophy combined with late onset Alzheimer's disease: a clinico-pathological case report.
Journal of the neurological sciences, 1998Co-Authors: Katsuji Kobayashi, Kiminori Isaki, K. Miyazu, Kazuo Sasaki, M. Hayashi, Yuken Fukutani, F. Muramori, T. Aoki, Masami Mukai, Yoshifumi KoshinoAbstract:A 76-year-old woman with olivopontocerebellar atrophy (OPCA) presented with progressive intellectual deterioration. She showed cerebellar ataxia and muscle atrophy and weakness, and gradually developed generalized dementia with visuospatial disturbance. An autopsy revealed numerous senile plaques (SPs), neurofibrillary tangles (NFTs) and neuropil threads particularly in the CA1, subiculum and entorhinal cortex and to a lesser degree in the cerebral neocortex shown by immunostaining and specific Silver Impregnation techniques. The nucleus basalis of Meynert had numerous NFTs with fibrillary gliosis and neuronal cell loss. The basis pontis was markedly atrophied and the pontine nucleus had severe neuronal depopulation and gliosis. The pontine transverse fibers were demyelinated with their axons being fragmented. The cerebellar white matter was also severely degenerated. The striatum, Onuf's and intermediolateral nuclei of the spinal cord remained unchanged. Ubiquitin immunohistochemistry and Gallyas Silver Impregnation technique revealed oligodendroglial inclusions in the pontine nucleus, corticopontine tract, cerebral and cerebellar white matter. On double immunostaining of KP1 and ubiquitin, globular neurite SPs encircled by KP1-positive fibrous structures were found in the hippocampus and cerebral neocortex. The curly neurite SPs contained KP1-positive granules. The KP1-positive microglial cells were distributed widely in the cerebral white matter and HLA-DR-positive ones were found around the SPs. The present case showed generalized dementia compatible with Alzheimer's disease (AD) and had a pathologically limbic type of late onset AD. This is the first case where AD affected non-familial OPCA.
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Cytoskeletal protein abnormalities in patients with olivopontocerebellar atrophy--an immunocytochemical and Gallyas Silver Impregnation study.
Neuropathology and applied neurobiology, 1992Co-Authors: K. Kobayashi, Ichiro Nakamura, Kazuhiko Katsukawa, K. Miyazu, Y. Fukutani, M. Mukai, R. Matsubara, Nariyoshi Yamaguchi, Kiminori IsakiAbstract:A highly sensitive Silver technique for glial cytoplasmic inclusions (GCI) in olivopontocerebellar atrophy (OPCA) was applied to tissues from 15 patients with neurodegenerative disorders including OPCA, Joseph disease, Alzheimer's disease (AD), Huntington's chorea, Pick disease and three control non-neurological subjects. Brain tissue from both OPCA and AD impregnated positively. Neurons, astroglia and oligodendroglia in the putamen, pontine nucleus and inferior olivary nucleus all impregnated in addition to white matter oligodendroglia. Neuronal inclusions in the pontine nucleus appeared as compact or fibrillary masses, and GCI-bearing oligodendroglia and astrocytes showed homogeneously impregnated somata. The myelinated pontocerebellar tract and the white matter surrounding the inferior olivary nucleus contained a small number of impregnated nerve fibres with a hollow structure, which resembled the myelin sheath. Immunocytochemical studies to clarify these argyrophilic structures in the OPCA subjects employed paired helical filament (PHF), microtubule associated proteins (MAPs), MAP1, MAP2, MAP5, tau, ubiquitin, neurofilament (200 or 70 kilodaltons) and myelin basic protein (MBP) antisera. GCI-bearing white matter oligodendroglia expressed PHF, tau, MAP5 and ubiquitin immunoreactives and non-argyrophilic astroglia were positive for MAP5 antiserum alone. In the putamen, pontine nuclei and inferior olivary nuclei, impregnated neurons as well as the GCI-bearing oligodendroglia immunostained with PHF, tau, MAP5 and ubiquitin antisera and impregnated astroglia were also immunoreactive to these antisera except for being tau negative in the putamen. Silver impregnated nerve fibres showed only MBP immunoreactivity. These findings indicate that the argyrophilia in the OPCA subjects closely correlates with PHF and tau immunoreactivities.
Folkert Postema - One of the best experts on this subject based on the ideXlab platform.
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induction of glial fibrillary acidic protein immunoreactivity in the rat dentate gyrus after adrenalectomy comparison with neurodegenerative changes using Silver Impregnation
Hippocampus, 1994Co-Authors: Hj Krugers, Folkert Postema, Rikje M Medema, Jakob KorfAbstract:In the present study we performed a light microscopic anatomical comparison of adrenalectomy (ADX)-induced neurodegeneration using Silver Impregnation and reaction of astroglial cells using GFAP immunocytochemistry in the hippocampus of the rat. Three survival times following ADX were studied: 24 hours, 3 days, and 3 weeks. Twenty-four hours following ADX we found no degenerative changes or altered GFAP immunostaining. Three days after adrenalectomy, argyrophilic somata appeared in the granular cell layer of the dentate gyrus. Argyrophilic dendrites were seen in the molecular layer of the dentate gyrus and neuritic argyrophilia were seen in the mossy fiber layer. Induction of GFAP immunoreactivity occurred simultaneously with degeneration. Increased GFAP immunoreactivity could be observed 3 days after adrenalectomy in the molecular layer of the dentate gyrus, granular cell layer, sub and supragranular cell layer, and mossy fiber layer. Size and shape of astroglial cells were changed, and their processes in the molecular layer changed from unidirectional to randomly organized. Degeneration and astroglial reaction were more pronounced 3 weeks after adrenalectomy and both were prevented by adding corticosterone to the drinking solution. Animals that did not show degenerative changes showed no increased GFAP immunoreactivity, while both effects were confined to the dentate gyrus and mossy fiber zone. These results show that there is a close relationship between the induction of GFAP immunoreactivity in the hippocampus of the rat and neuronal degeneration in the dentate gyrus following ADX, both in time and space.
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Time course and distribution of neuronal degeneration in the dentate gyrus of rat after adrenalectomy: a Silver Impregnation study.
Hippocampus, 1992Co-Authors: Dick Jaarsma, Folkert Postema, Jakob KorfAbstract:Recently, Sloviter et al. reported that adrenalectomy (ADX) of young adult rats after 3 months led to a selective loss of granule neurons in the dentate gyrus (DG) and that this loss could be prevented by low doses of corticosterone. In the present study, the ADX-induced neuronal degeneration was investigated in Wistar rats, using a Silver Impregnation method for degenerating neurons. To examine the time course and distribution of the ADX-induced degeneration, young adult male rats were allowed to survive 2, 3, and 5 days and 1, 2, and 3 weeks after ADX. Argyrophilic neurons were present in the dentate granule cell layer on the second day following ADX. Three days after ADX, the number of argyrophilic granule neurons was much more abundant, and it increased gradually with longer post-ADX survival times. Argyrophilia was specifically confined to dentate granule cells and was accompanied by the occurrence of pyknotic nuclei as observed in adjacent cresyl violet-stained sections. There were significant differences between individual rats in quantity of argyrophilia. About one fifth of the ADX rats showed sporadic or no argyrophilia, in spite of plasma corticosterone levels below the detection limit (10 ng/mL). Sham-operated rats and ADX rats receiving corticosterone (10 mg/L) or dexamethasone (15 mg/L) in their drinking water did not display any argyrophilic neurons in the dentate gyrus. The distribution of the argyrophilia within the DG was highly characteristic with the highest number of degenerating cells in the hidden blade of the middle and the temporal thirds of the DG.(ABSTRACT TRUNCATED AT 250 WORDS)
Hj Krugers - One of the best experts on this subject based on the ideXlab platform.
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Induction of glial fibrillary acidic protein immunoreactivity in the rat dentate gyrus after adrenalectomy: Comparison with neurodegenerative changes using Silver Impregnation
1994Co-Authors: Hj Krugers, Postema F, Rm Medema, Korf JAbstract:In the present study we performed a light microscopic anatomical comparison of adrenalectomy (ADX)-induced neurodegeneration using Silver Impregnation and reaction of astroglial cells using GFAP immunocytochemistry in the hippocampus of the rat. Three survival times following ADX were studied: 24 hours, 3 days, and 3 weeks. Twenty-four hours following ADX we found no degenerative changes or altered GFAP immunostaining. Three days after adrenalectomy, argyrophilic somata appeared in the granular cell layer of the dentate gyrus. Argyrophilic dendrites were seen in the molecular layer of the dentate gyrus and neuritic argyrophilia were seen in the messy fiber layer. Induction of GFAP immunoreactivity occurred simultaneously with degeneration. Increased GFAP immunoreactivity could be observed 3 days after adrenalectomy in the molecular layer of the dentate gyrus, granular cell layer, sub and supragranular cell layer, and messy fiber layer. Size and shape of astroglial cells were changed, and their processes in the molecular layer changed from unidirectional to randomly organized. Degeneration and astroglial reaction were more pronounced 3 weeks after adrenalectomy and both were prevented by adding corticosterone to the drinking solution. Animals that did not show degenerative changes showed no increased GFAP immunoreactivity, while both effects were confined to the dentate gyrus and messy fiber zone. These results show that there is a close relationship between the induction of GFAP immunoreactivity in the hippocampus of the rat and neuronal degeneration in the dentate gyrus following ADX, both in time and space. (C) 1994 Wiley-Liss, Inc
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induction of glial fibrillary acidic protein immunoreactivity in the rat dentate gyrus after adrenalectomy comparison with neurodegenerative changes using Silver Impregnation
Hippocampus, 1994Co-Authors: Hj Krugers, Folkert Postema, Rikje M Medema, Jakob KorfAbstract:In the present study we performed a light microscopic anatomical comparison of adrenalectomy (ADX)-induced neurodegeneration using Silver Impregnation and reaction of astroglial cells using GFAP immunocytochemistry in the hippocampus of the rat. Three survival times following ADX were studied: 24 hours, 3 days, and 3 weeks. Twenty-four hours following ADX we found no degenerative changes or altered GFAP immunostaining. Three days after adrenalectomy, argyrophilic somata appeared in the granular cell layer of the dentate gyrus. Argyrophilic dendrites were seen in the molecular layer of the dentate gyrus and neuritic argyrophilia were seen in the mossy fiber layer. Induction of GFAP immunoreactivity occurred simultaneously with degeneration. Increased GFAP immunoreactivity could be observed 3 days after adrenalectomy in the molecular layer of the dentate gyrus, granular cell layer, sub and supragranular cell layer, and mossy fiber layer. Size and shape of astroglial cells were changed, and their processes in the molecular layer changed from unidirectional to randomly organized. Degeneration and astroglial reaction were more pronounced 3 weeks after adrenalectomy and both were prevented by adding corticosterone to the drinking solution. Animals that did not show degenerative changes showed no increased GFAP immunoreactivity, while both effects were confined to the dentate gyrus and mossy fiber zone. These results show that there is a close relationship between the induction of GFAP immunoreactivity in the hippocampus of the rat and neuronal degeneration in the dentate gyrus following ADX, both in time and space.