The Experts below are selected from a list of 2574 Experts worldwide ranked by ideXlab platform
Shigenobu Shibata - One of the best experts on this subject based on the ideXlab platform.
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Circadian profile of Per gene mRNA expression in the suprachiasmatic nucleus, paraventricular nucleus, and Pineal Body of aged rats
Journal of neuroscience research, 2001Co-Authors: Makoto Asai, Yuko Yoshinobu, Satoshi Kaneko, Akiko Mori, Takato Nikaido, Takahiro Moriya, Masashi Akiyama, Shigenobu ShibataAbstract:Aging alters circadian components such as the free-running period, the day-to-night activity ratio and photic entrainment in behavioral rhythms, and 2-deoxyglucose uptakes and neuronal firing in the suprachiasmatic nucleus (SCN). A core clock mechanism in the mouse SCN appears to involve a transcriptional feedback loop in which Period (Per) and Cryptochrome (Cry) genes play a role in negative feedback. The circadian rhythm systems include photic entrainment, clock oscillation, and outputs of clock information such as melatonin production. In this experiment, we examined clock gene expression to determine whether circadian input, oscillation, and output are disrupted with aging. Circadian expression profiles of rPer1, rPer2, or rCry1 mRNA were very similar in the SCN, the paraventricular nucleus of the hypothalamus (PVN), and the Pineal Body of young and aged (22-26 months) rats. On the other hand, the photic stimulation-induced rapid expression of Per1 and Per2 in the SCN was reduced with aging. The present results suggest that the molecular mechanism of clock oscillation in the SCN, PVN, and Pineal Body is preserved against aging, whereas the impairment of Per1 induction in the SCN after light stimulation may result in impaired behavioral photic entrainment in aged rats.
Akira Teramoto - One of the best experts on this subject based on the ideXlab platform.
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Spontaneous regression of a germinoma in the Pineal Body after placement of a ventriculoperitoneal shunt.
Journal of neurosurgery, 2000Co-Authors: Yasuo Murai, Shiro Kobayashi, Takayuki Mizunari, Yoshiharu Ohaki, Koji Adachi, Akira TeramotoAbstract:The authors report a case in which a germinoma in the Pineal Body displayed spontaneous regression after placement of a ventriculoperitoneal (VP) shunt. Spontaneous regression of malignant tumors is extremely rare, occurring in only one of 60,000 to 100,000 patients. Although in rare cases spontaneous regression is known to occur in patients with testicular seminomas, only one case of spontaneous regression of a primary Pineal germinoma has so far been reported. In the present case a 17-year-old man presented with headache. A tumor in the Pineal Body and acute hydrocephalus were revealed by head computerized tomography (CT) and magnetic resonance (MR) imaging, and VP shunt placement was performed. Computerized tomography scanning of the head was performed four times during a 2-week period following the operation, and the patient was temporarily discharged to return to school. At the time of discharge, CT scanning demonstrated no change in the size of the tumor. Two months later, the patient was readmitted to the hospital to undergo surgery. At that time, head MR imaging revealed regression of the tumor. The pathological diagnosis of the lesion was germinoma. The patient underwent three courses of chemotherapy, during which carboplatin and etoposide were administered, in addition to a 24-Gy dose of radiotherapy. No manifestations of nerve impairment were noticed, and the patient was observed on an outpatient basis. The authors think that the factors involved in tumor regression included the effects of the VP shunt, the effects of radiation absorbed during head CT scanning, and the role of the patient's own immune response. However, no conclusion has been reached concerning the actual cause.
Makoto Asai - One of the best experts on this subject based on the ideXlab platform.
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Circadian profile of Per gene mRNA expression in the suprachiasmatic nucleus, paraventricular nucleus, and Pineal Body of aged rats
Journal of neuroscience research, 2001Co-Authors: Makoto Asai, Yuko Yoshinobu, Satoshi Kaneko, Akiko Mori, Takato Nikaido, Takahiro Moriya, Masashi Akiyama, Shigenobu ShibataAbstract:Aging alters circadian components such as the free-running period, the day-to-night activity ratio and photic entrainment in behavioral rhythms, and 2-deoxyglucose uptakes and neuronal firing in the suprachiasmatic nucleus (SCN). A core clock mechanism in the mouse SCN appears to involve a transcriptional feedback loop in which Period (Per) and Cryptochrome (Cry) genes play a role in negative feedback. The circadian rhythm systems include photic entrainment, clock oscillation, and outputs of clock information such as melatonin production. In this experiment, we examined clock gene expression to determine whether circadian input, oscillation, and output are disrupted with aging. Circadian expression profiles of rPer1, rPer2, or rCry1 mRNA were very similar in the SCN, the paraventricular nucleus of the hypothalamus (PVN), and the Pineal Body of young and aged (22-26 months) rats. On the other hand, the photic stimulation-induced rapid expression of Per1 and Per2 in the SCN was reduced with aging. The present results suggest that the molecular mechanism of clock oscillation in the SCN, PVN, and Pineal Body is preserved against aging, whereas the impairment of Per1 induction in the SCN after light stimulation may result in impaired behavioral photic entrainment in aged rats.
Hou Yanmeng - One of the best experts on this subject based on the ideXlab platform.
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Season-related changes of the ultrastructure and distribution of serotonin(5-HT) of Laiwu black goat's Pineal Body
Chinese journal of veterinary science, 2008Co-Authors: Hou YanmengAbstract:Pineal bodies of Laiwu black goat during four seasons were investigated by immunohistochemical SABC method and TEM.The results are as follows:A great number of 5-HT-containing cells and fibers are found in the Pineal Body.When the seasons compared,the area of 5-HT-containing cell in winter is obviously higher than that of other seasons(P0.01).Summer is the lowest season.Spring and autumn are almost the same(P0.05).The difference value of the four seasons is almost the same(P0.05).The ratio of 5-HT-containing area in Pineal Body between different seasons are analyzed.There is no significant difference between sping and autumn(P0.05).But there is significant difference between random other seasons(P0.01).Pinealocytes could be classified into dark cell and light cell.Their ultrastructure is different.In the light cell,nuclei is larger,with plentiful euchromatin.RER and free ribosomes are abundant.The saccules in Golgi complex is multiplayer.The quantity of mitochondrial crista is affluence.Glycogen is not abundant.In the dark cell,heterochromatin is plentiful in the nuclei.RER and free ribosome are not abundant.Saccules in Golgi complex is deficiency.The quantity of mitochondrial crista is scarce.Glycogen is plentiful.The outcome suggests that the function of light cell might be stronger than the dark cell.Comparing four seasons,the light cell in winter present dominanty,in summer the dark cell dominanty.Both of the two kinds of cells are found in sping and autumn.The results indicate that season can influence the functional and ultrastructure of the Pinealocyte.
Yasuo Murai - One of the best experts on this subject based on the ideXlab platform.
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Spontaneous regression of a germinoma in the Pineal Body after placement of a ventriculoperitoneal shunt.
Journal of neurosurgery, 2000Co-Authors: Yasuo Murai, Shiro Kobayashi, Takayuki Mizunari, Yoshiharu Ohaki, Koji Adachi, Akira TeramotoAbstract:The authors report a case in which a germinoma in the Pineal Body displayed spontaneous regression after placement of a ventriculoperitoneal (VP) shunt. Spontaneous regression of malignant tumors is extremely rare, occurring in only one of 60,000 to 100,000 patients. Although in rare cases spontaneous regression is known to occur in patients with testicular seminomas, only one case of spontaneous regression of a primary Pineal germinoma has so far been reported. In the present case a 17-year-old man presented with headache. A tumor in the Pineal Body and acute hydrocephalus were revealed by head computerized tomography (CT) and magnetic resonance (MR) imaging, and VP shunt placement was performed. Computerized tomography scanning of the head was performed four times during a 2-week period following the operation, and the patient was temporarily discharged to return to school. At the time of discharge, CT scanning demonstrated no change in the size of the tumor. Two months later, the patient was readmitted to the hospital to undergo surgery. At that time, head MR imaging revealed regression of the tumor. The pathological diagnosis of the lesion was germinoma. The patient underwent three courses of chemotherapy, during which carboplatin and etoposide were administered, in addition to a 24-Gy dose of radiotherapy. No manifestations of nerve impairment were noticed, and the patient was observed on an outpatient basis. The authors think that the factors involved in tumor regression included the effects of the VP shunt, the effects of radiation absorbed during head CT scanning, and the role of the patient's own immune response. However, no conclusion has been reached concerning the actual cause.