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Tibor Donáth - One of the best experts on this subject based on the ideXlab platform.
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Ultrastructural cytochemistry of acetylcholinesterase enzyme activity in pancreatic tissue transplants in rats.
Cell Transplantation, 1994Co-Authors: Ernest Adeghate, Tibor DonáthAbstract:: The distribution of acetylcholinesterase (AChE) at the ultrastructural level was investigated in normal and in pancreatic fragments transplanted for 56 days into the Anterior Eye Chamber of heterologous rats using enzyme cytochemical methods. Acetylcholinesterase reaction products were seen on the basal surface of the acinar cells in normal pancreas. Acetylcholinesterase enzyme activity was also detected on the axolemma of the surviving nerve fibres. This enzyme reaction product forms alternating thick and thin bands on the axolemma. Some of these AChE-positive nerve fibres accompany blood vessels that also survive after transplantation. AChE were seen in cytoplasm adjacent to the surviving alpha and pancreatic polypeptide cells. We conclude that the ability of some neurons and cells to produce and or store acetylcholinesterase is still retained after transplantation of pancreatic tissue into the Anterior Eye Chamber of rats.
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Dopamine-beta-hydroxylase-positive nerves in normal and transplanted pancreatic tissue in the Anterior Eye-Chamber of rats.
Journal of Chemical Neuroanatomy, 1991Co-Authors: Ernest Adeghate, Tibor DonáthAbstract:Abstract Dopamine-beta-hydroxylase(DBH)-positive nerves were demonstrated in normal and in pancreatic tissue fragments transplanted for 22 and 32 days into the Anterior Eye-Chamber of rats using immunohistochemical techniques. Dopamine-beta-hydroxylase-immunopositive neurons of different shapes could be observed in normal pancreas. The neurons had either spindle or oval shapes. In the transplanted tissue, DBH-positive neuronal profiles were found in the stroma. In some cases DBH-immunopositive cells appeared as a cluster of cells around pancreatic ducts and blood vessels or as solitary cells. The wall of pancreatic ducts in the transplants also contained DBH-immunopositive nerve profiles.
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Distribution of neuropeptide Y and vasoactive intestinal polypeptide immunoreactive nerves in normal and transplanted pancreatic tissue.
Peptides, 1990Co-Authors: Ernest Adeghate, Tibor DonáthAbstract:Neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP) immunoreactive nerves were demonstrated in 21-day-old embryonic pancreatic tissue fragments transplanted into the Anterior Eye Chamber of rats for 22, 45 and 109 days and in 60-day-old normal adult pancreas using immunohistochemical technique. In normal adult tissue, NPY-positive neurons lie close to the basal and lateral walls of the acinar cells. NPY-containing nerve fiber plexuses were found around blood vessels. VIP-immunopositive nerves were also discernible in the outer parts of the islets of Langerhans and on pancreatic ducts. In the transplants, it is not only the neural elements that survived but also the pancreatic ducts and the endocrine cells. VIP- and NPY-positive neurons were found in the stroma of the surviving pancreatic tissue. The distribution of these neural elements is similar to that of normal tissue in the surviving pancreatic ducts but different with regards to the acinar tissue. This study confirms that intrinsic nerves can survive and synthesize polypeptides even after 109 days of transplantation into the Anterior Eye Chamber.
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Morphological findings in long-term pancreatic tissue transplants in the Anterior Eye Chamber of rats.
Pancreas, 1990Co-Authors: Ernest Adeghate, Tibor DonáthAbstract:: Morphological changes in 21-day-old embryonic and 2-day-old postnatal rat pancreatic tissue fragments transplanted into the Anterior Eye Chamber of homologous animals for 74, 77, 180, and 534 days were investigated using light and electron microscopic, acetylcholinesterase enzyme, and immunohistochemical methods. The pancreatic acinar cells degenerated and were not observed at this stage of transplantation. The ductal system proliferated and partly differentiated into endocrine cells that subsequently formed many new islets of Langerhans as well. The structures of beta-, alpha-, delta-, and pancreatic polypeptide cells were found to be intact even 1.5 years after transplantation. In addition to this, the organization of these cells inside the islets is similar to that of normal pancreatic tissue. The transplanted tissue fragments were well vascularized with blood vessels and innervated also by serotonergic cells and acetylcholinesterase-positive neurons. It is concluded that pancreatic tissue fragments, with the exception of the acinar component, can grow and survive with intact structure in the Anterior Eye Chamber of homologous rats for up to 1.5 years.
Mitsuhiro Kawata - One of the best experts on this subject based on the ideXlab platform.
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The histochemical study of the effects of estrogen on the forebrain cholinergic neurons of fetal female rats transplanted into the Anterior Eye Chamber of adult female rats
Folia Endocrinologica Japonica, 1993Co-Authors: K. Tanaka, Mitsuhiro Kawata, Takaya Tamura, Kawashima M, S. Ueda, Y. Matsumoto, Y. Ogino, Takara Yamamoto, Hideo Honjo, Hiroji OkadaAbstract:: In order to clarify the effects of estrogen on cholinergic basal forebrain neurons, a cholinergic neuron in the diagonal band nucleus of the female fetal rat was implanted into the Anterior Eye Chamber of the female adult rat. Some host rats were treated with 2mg estradiol valerate (E2v) injected every 3 days after ovariectomy while others were not 2 and 4 weeks after transplantation, the growth of cholinergic neurons in the graft was studied using acethylcholinesterase (AChE) histochemistry. At 2 weeks after transplantation, AChE positive neurons and fibers were densely distributed in the grafts of E2v treated rats. Also in grafts without E2v treatment, AChE positive neurons and fibers were found in all the grafts although their density was low. At 4 weeks, AChE staining was dense staining observed in both groups. These results indicate that neurotrophic effect of estrogen on the cholinergic basal forebrain neurons.
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estrogen as a growth factor to central nervous cells estrogen treatment promotes development of acetylcholinesterase positive basal forebrain neurons transplanted in the Anterior Eye Chamber
The Journal of Steroid Biochemistry and Molecular Biology, 1992Co-Authors: Hideo Honjo, Mitsuhiro Kawata, K. Tanaka, Takaya Tamura, S. Ueda, Y. Matsumoto, Y. Ogino, Takara Yamamoto, Hiroji OkadaAbstract:Abstract 3n a previous report, we demonstrated in vivo ameliorating effects of conjugated estrogen in women suffering from senile dementia-Alzheimer's type. To investigate the effects of estrogen on the growth of cholinergic neurons, the present study was performed using rat cholinergic tissue implanted into the Anterior Chamber of the Eye. Fetal diagonal band tissue containing cholinergic neurons was grafted into the Anterior Eye Chamber of adult female rats that had either been treated or not with 2 mg estradiol valerate injected every 3 days after oophrectomy. Two and four weeks after transplantation, the axonal and/or dendritic growth of cholinergic neurons in the graft was studied using acetylcholinesterase histochemistry. At both times, acetylcholinesterase positive processes were densely distributed in the grafts of estradiol valerate treated rats, while in rats without estradiol valerate treatment acetylcholinesterase positive reaction was essentially localized only on the cell bodies. These findings were more obvious at 2 weeks after transplantation than at 4 weeks. These results suggest that estrogen acts on cholinergic neurons as a growth factor.
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Target-specific innervation by autonomic and sensory nerve fibers in hairy fetal skin transplanted into the Anterior Eye Chamber of adult rat
Cell and Tissue Research, 1991Co-Authors: Norito Katoh, Shuichi Ueda, Yasuhiro Matsumoto, Saburo Kishimoto, Hirokazu Yasuno, Mitsuhiro KawataAbstract:Pieces of hairy skin tissue of fetal rat were transplanted into the Anterior Eye Chamber of adult rats. The ability of autonomic and sensory nerve fibers from the host iris to innervate the grafted skin tissue was immunohistochemically and enzyme-histochemically examined using antisera against tyrosine hydroxylase (TH), substance P (SP), calcitonin gene-related peptide (CGRP) and vasoactive intestinal peptide (VIP), and a reaction medium for acetylcholinesterase (AchE). The grafted tissue was successfully implanted and connected with the host iris. Epidermis, dermis, subcutaneous tissue, hairs, hair follicles, sebaceous glands, and piloerector muscles developed in the graft. Two weeks after transplantation, TH-, SP-, and CGRP-immunoreactive fibers were observed in association with the blood vessels in the graft. Four weeks after transplantation, TH-immunoreactive fibers were distributed in the piloerector muscles, whereas SP-and CGRP-immunoreactive fibers were present around the hair follicles. VIP-immunoreactive and AchE-positive fibers were restricted to the host iris at all survival times. These results suggest that the outgrowth of autonomic and sensory nerve fibers from the host iris show target specificity for the grafted skin tissue.
Ernest Adeghate - One of the best experts on this subject based on the ideXlab platform.
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Comparative morphology and biochemistry of pancreatic tissue fragments transplanted into the Anterior Eye Chamber and subcutaneous regions of the rat.
European Journal of Morphology, 2001Co-Authors: Ernest Adeghate, A. S. Ponery, I. Ahmed, Donáth TAbstract:: The present study was designed to compare the morphological changes occurring in pancreatic tissue fragments transplanted into the Anterior Eye Chamber (AEC) and the subcutaneous (SC) regions of the rat. Pancreatic tissue segments were removed from the tail end of the pancreas of neonatal rats and transplanted into the AEC and SC region of the neck of homologous rats. Five weeks after transplantation, the grafts were removed and processed for light microscopy, immunohistochemistry and radioimmunoassay. In both pancreatic tissue grafts, the acinar cells degenerated completely after transplantation. In contrast to this, insulin-, glucagon-, somatostatin- and pancreatic polypeptide-positive cells and pancreatic ducts survived equally well in both the AEC and SC grafts. The pattern and percentage distribution of insulin-, glucagon-, somatostatin- and PP-producing cells in the AEC and SC grafts was similar to that observed in normal pancreas. However, the percentage distribution of glucagon- and PP-containing cells was significantly (p < 0.03) lower in SC grafts when compared to normal. Radioimmunoassay showed that the AEC and SC pancreatic tissue grafts contained large quantities of insulin and glucagon. However, the insulin content of AEC was slightly but not significantly higher than that of SC grafts. The protein content of pancreatic tissue grafts in these transplantation sites was still significantly (p < 0.05) lower compared to normal. Lymphatic infiltration was also more conspicuous in SC grafts compared to AEC grafts. This infiltration by lymphatic cells was confined only to the endocrine portion of the graft. In conclusion, pancreatic tissue grafts survived in both the AEC and SC regions of rats but the AEC appears to be more conducive to graft survival than the SC region.
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Ultrastructural cytochemistry of acetylcholinesterase enzyme activity in pancreatic tissue transplants in rats.
Cell Transplantation, 1994Co-Authors: Ernest Adeghate, Tibor DonáthAbstract:: The distribution of acetylcholinesterase (AChE) at the ultrastructural level was investigated in normal and in pancreatic fragments transplanted for 56 days into the Anterior Eye Chamber of heterologous rats using enzyme cytochemical methods. Acetylcholinesterase reaction products were seen on the basal surface of the acinar cells in normal pancreas. Acetylcholinesterase enzyme activity was also detected on the axolemma of the surviving nerve fibres. This enzyme reaction product forms alternating thick and thin bands on the axolemma. Some of these AChE-positive nerve fibres accompany blood vessels that also survive after transplantation. AChE were seen in cytoplasm adjacent to the surviving alpha and pancreatic polypeptide cells. We conclude that the ability of some neurons and cells to produce and or store acetylcholinesterase is still retained after transplantation of pancreatic tissue into the Anterior Eye Chamber of rats.
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Dopamine-beta-hydroxylase-positive nerves in normal and transplanted pancreatic tissue in the Anterior Eye-Chamber of rats.
Journal of Chemical Neuroanatomy, 1991Co-Authors: Ernest Adeghate, Tibor DonáthAbstract:Abstract Dopamine-beta-hydroxylase(DBH)-positive nerves were demonstrated in normal and in pancreatic tissue fragments transplanted for 22 and 32 days into the Anterior Eye-Chamber of rats using immunohistochemical techniques. Dopamine-beta-hydroxylase-immunopositive neurons of different shapes could be observed in normal pancreas. The neurons had either spindle or oval shapes. In the transplanted tissue, DBH-positive neuronal profiles were found in the stroma. In some cases DBH-immunopositive cells appeared as a cluster of cells around pancreatic ducts and blood vessels or as solitary cells. The wall of pancreatic ducts in the transplants also contained DBH-immunopositive nerve profiles.
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Distribution of neuropeptide Y and vasoactive intestinal polypeptide immunoreactive nerves in normal and transplanted pancreatic tissue.
Peptides, 1990Co-Authors: Ernest Adeghate, Tibor DonáthAbstract:Neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP) immunoreactive nerves were demonstrated in 21-day-old embryonic pancreatic tissue fragments transplanted into the Anterior Eye Chamber of rats for 22, 45 and 109 days and in 60-day-old normal adult pancreas using immunohistochemical technique. In normal adult tissue, NPY-positive neurons lie close to the basal and lateral walls of the acinar cells. NPY-containing nerve fiber plexuses were found around blood vessels. VIP-immunopositive nerves were also discernible in the outer parts of the islets of Langerhans and on pancreatic ducts. In the transplants, it is not only the neural elements that survived but also the pancreatic ducts and the endocrine cells. VIP- and NPY-positive neurons were found in the stroma of the surviving pancreatic tissue. The distribution of these neural elements is similar to that of normal tissue in the surviving pancreatic ducts but different with regards to the acinar tissue. This study confirms that intrinsic nerves can survive and synthesize polypeptides even after 109 days of transplantation into the Anterior Eye Chamber.
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Morphological findings in long-term pancreatic tissue transplants in the Anterior Eye Chamber of rats.
Pancreas, 1990Co-Authors: Ernest Adeghate, Tibor DonáthAbstract:: Morphological changes in 21-day-old embryonic and 2-day-old postnatal rat pancreatic tissue fragments transplanted into the Anterior Eye Chamber of homologous animals for 74, 77, 180, and 534 days were investigated using light and electron microscopic, acetylcholinesterase enzyme, and immunohistochemical methods. The pancreatic acinar cells degenerated and were not observed at this stage of transplantation. The ductal system proliferated and partly differentiated into endocrine cells that subsequently formed many new islets of Langerhans as well. The structures of beta-, alpha-, delta-, and pancreatic polypeptide cells were found to be intact even 1.5 years after transplantation. In addition to this, the organization of these cells inside the islets is similar to that of normal pancreatic tissue. The transplanted tissue fragments were well vascularized with blood vessels and innervated also by serotonergic cells and acetylcholinesterase-positive neurons. It is concluded that pancreatic tissue fragments, with the exception of the acinar component, can grow and survive with intact structure in the Anterior Eye Chamber of homologous rats for up to 1.5 years.
Johannes L. J. M. Teepen - One of the best experts on this subject based on the ideXlab platform.
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Short report: Churg Strauss syndrome (allergic granulomatous angiitis) as a cause of central retinal artery occlusion
Neuro-Ophthalmology, 2009Co-Authors: Louis A. K. Bastiaensen, George E. M. Kienstra, Willem P. L. Van Boven, Johannes L. J. M. TeepenAbstract:A case of Churg Strauss syndrome (CSS) with central retinal artery occlusion is presented. This is the second fully documented case of such an event in CSS, but very probably not as a fortuitous coincidence. The patient recovered from his retinal arterial occlusion after paracentesis of the Anterior Eye Chamber; the systemic signs and symptoms cleared slowly upon administration of corticosteroids and cyclophosphamide.
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Churg Strauss syndrome (allergic granulomatous angiitis) as a cause of central retinal artery occlusion
1993Co-Authors: Louis A. K. Bastiaensen, George E. M. Kienstra, Willem P. L. Van Boven, Johannes L. J. M. TeepenAbstract:A case of Churg Strauss syndrome (CSS) with central retinal artery occlusion is presented. This is the second fully documented case of such an event in CSS, but very probably not as a fortuitous coincidence. The patient recovered from his retinal arterial occlusion after paracentesis of the Anterior Eye Chamber; the systemic signs and symptoms cleared slowly upon administration of corticosteroids and cyclophosphamide.
Hiroji Okada - One of the best experts on this subject based on the ideXlab platform.
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The histochemical study of the effects of estrogen on the forebrain cholinergic neurons of fetal female rats transplanted into the Anterior Eye Chamber of adult female rats
Folia Endocrinologica Japonica, 1993Co-Authors: K. Tanaka, Mitsuhiro Kawata, Takaya Tamura, Kawashima M, S. Ueda, Y. Matsumoto, Y. Ogino, Takara Yamamoto, Hideo Honjo, Hiroji OkadaAbstract:: In order to clarify the effects of estrogen on cholinergic basal forebrain neurons, a cholinergic neuron in the diagonal band nucleus of the female fetal rat was implanted into the Anterior Eye Chamber of the female adult rat. Some host rats were treated with 2mg estradiol valerate (E2v) injected every 3 days after ovariectomy while others were not 2 and 4 weeks after transplantation, the growth of cholinergic neurons in the graft was studied using acethylcholinesterase (AChE) histochemistry. At 2 weeks after transplantation, AChE positive neurons and fibers were densely distributed in the grafts of E2v treated rats. Also in grafts without E2v treatment, AChE positive neurons and fibers were found in all the grafts although their density was low. At 4 weeks, AChE staining was dense staining observed in both groups. These results indicate that neurotrophic effect of estrogen on the cholinergic basal forebrain neurons.
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estrogen as a growth factor to central nervous cells estrogen treatment promotes development of acetylcholinesterase positive basal forebrain neurons transplanted in the Anterior Eye Chamber
The Journal of Steroid Biochemistry and Molecular Biology, 1992Co-Authors: Hideo Honjo, Mitsuhiro Kawata, K. Tanaka, Takaya Tamura, S. Ueda, Y. Matsumoto, Y. Ogino, Takara Yamamoto, Hiroji OkadaAbstract:Abstract 3n a previous report, we demonstrated in vivo ameliorating effects of conjugated estrogen in women suffering from senile dementia-Alzheimer's type. To investigate the effects of estrogen on the growth of cholinergic neurons, the present study was performed using rat cholinergic tissue implanted into the Anterior Chamber of the Eye. Fetal diagonal band tissue containing cholinergic neurons was grafted into the Anterior Eye Chamber of adult female rats that had either been treated or not with 2 mg estradiol valerate injected every 3 days after oophrectomy. Two and four weeks after transplantation, the axonal and/or dendritic growth of cholinergic neurons in the graft was studied using acetylcholinesterase histochemistry. At both times, acetylcholinesterase positive processes were densely distributed in the grafts of estradiol valerate treated rats, while in rats without estradiol valerate treatment acetylcholinesterase positive reaction was essentially localized only on the cell bodies. These findings were more obvious at 2 weeks after transplantation than at 4 weeks. These results suggest that estrogen acts on cholinergic neurons as a growth factor.
