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71.
Peng W Premkumar A Mossner R Fukuda M Lesch KP Simantov R 《Brain research. Molecular brain research》2002,108(1-2):94-101
3,4-Methylenedioxymethamphetamine (MDMA or Ecstasy) is a widely abused drug. In brains of mice exposed to MDMA, we recently detected altered expression of several cDNAs and genes by using the differential display polymerase chain reaction (PCR) method. Expression of one such cDNA, which exhibited 98% sequence homology with the synaptic vesicle protein synaptotagmin IV, decreased 2 h after MDMA treatment. Herein, the effect of MDMA on expression of both synaptotagmin I and IV was studied in detail, since the two proteins are functionally interrelated. PCR analyses (semi-quantitative and real-time) confirmed that upon treatment with MDMA, expression of synaptotagmin IV decreased both in the midbrain and frontal cortex of mice. Decreases in the protein levels of synaptotagmin IV were confirmed by Western immunoblotting with anti-synaptotagmin IV antibodies. In contrast, the same exposure to MDMA increased expression of synaptotagmin I in the midbrain, a region rich in serotonergic neurons, but not in the frontal cortex. This differential expression was confirmed at the protein level with anti-synaptotagmin I antibodies. MDMA did not induce down- or up-regulation of synaptotagmin IV and I, respectively, in serotonin transporter knockout mice (-/-) that are not sensitive to MDMA. Therefore, psychoactive drugs, such as MDMA, appear to modulate expression of synaptic vesicle proteins, and possibly vesicle trafficking, in the brain. 相似文献
72.
Fifty-five hematopoietic cell lines, including 19 T-, 16 B-, 5 pre-B-, 5 non-T non-B-, 1 erythroid, and 9 myeloid-monocytoid cells, were screened for production of human hematopoietic survival and stem cell growth factor (SCGF) by enzyme immunoassay using anti-SCGF monoclonal antibody. The KPB-M15 myeloid cell line constitutionally secreted a considerable quantity of SCGF, while other T- or myeloid-monocytoid cell lines did not secrete SCGF. Other biomaterials investigated were fetal calf, horse, and human serum; granulocyte-macrophage colony-stimulating factor and erythropoietin preparations; human placental conditioned medium; lectin (phytohemagglutinin, concanavalin A, and pokeweed mitogen); and mixed leukocyte reaction-stimulated leukocyte-conditioned medium. SCGF was detected only in human placental conditioned medium. SCGF produced by the KPB-M15 cells was a protein with a molecular weight of 20,000. The molecule, highly purified by immunoadsorbent affinity chromatography, retained SCGF activity in vitro, e.g., erythroid burst-promoting activity and granulocyte-macrophage-colony potentiation. With the availability of purified SCGF, it is now possible to study in detail the mechanisms regulating hematopoietic stem cells. 相似文献
73.
Z Q Yang M A Yoshida Y Fukuda N Kurihara Y Nakamura J Inazawa 《Japanese journal of cancer research》2000,91(2):156-163
Comparative genomic hybridization (CGH) was used to screen for genomic imbalances in cell lines derived from 13 nonpapillary renal-cell carcinomas (RCCs), two papillary RCCs, one renal squamous-cell carcinoma, and one transitional-cell carcinoma of the renal pelvis. Aberrations were found in all 17 lines. The most frequent changes in nonpapillary RCC cell lines were gains of 5q (85%), 7q (69%), 8q (69%) and 1q (54%) and losses of 3p (92%), 8p (77%), 4q (62%) and 14q (54%). High-level gains (HLGs) were detected at 4q12, 5p, 5q23-33, 7q22-qter, 8q23-24, 10q21-qter, 12p and 12q13-22. By means of fluorescence in situ hybridization (FISH) we narrowed the smallest common region involving 5q gains to the genomic segment between D5S642 and D5S673, and found that the HLG at 4q12 possibly involved amplifications of c-kit and PDGFRA. Two papillary RCC cell lines showed gains of entire chromosomes 7, 12 and 17. The CGH data reported here should help to facilitate the choice of individual renal-tumor cell lines for exploring target genes in regions of interest. 相似文献
74.
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76.
Although ventriculoperitoneal (V-P) shunt is common as the surgical procedure for hydrocephalus, mechanical malfunction and infection are the most significant problems. Despite the current use of variety of mechanical shunting systems, shunt malfunction remains a major problem in pediatric neurosurgical practice. Pathological lesions associated with malfunctioning shunts have been studied only infrequently. From April 1980 to December 1987, we experienced 96 cases of V-P shunt in neonates and suckling. The therapeutic results of shunting and causes of initial shunt revision in those cases with nontumoral hydrocephalus were studied. Of 96 cases, which included 55 cases of congenital and 41 cases of acquired hydrocephalus, in which a V-P shunt had been performed, those cases with no history of shunt revision or with only elective shunt revision during the 5-year follow-up period were classified as successful shunt. The 56 of 96 cases (58.3% successful shunts included 15 of 24 patients with myelomeningocele, 7 of 10 with encephalocele, 12 of 21 with various types of cerebral anomaly, 12 of 22 with posthemorrhagic hydrocephalus and 10 with postmeningitic hydrocephalus. There were 12 successful shunts performed in 27 premature and 44 in 69 mature infants. The 40 patients (41.7% with non-elective shunt revision included 5 with breakdown of the sutured scalp with cerebrospinal fluid leakage, 20 with obstruction of the shunt system (14 ventricular side, 6 abdominal side, and 15 with infection. During the 5-year follow-up period 11 died and 85 survived 88.5%), of whom 43 (44.8%) showed normal intellectual development and 42 (43.7%) showed developmental disability. 相似文献
77.
GABA was applied iontophoretically to dorsal and ventral lateral geniculate (LGd and LGv) neurons in rats. Spontaneous discharges were readily suppressed in both species of neurons. While in LGd neurons, evoked discharges by optic nerve stimulation were suppressed as readily as were spontaneous discharges, LGv neurons were characterized in that evoked discharges were much more resistant than spontaneous discharges. 相似文献
78.
Naoki Kumagai Shoji Nagakubo Tomomichi Kameyama Masato Fukuda Yukihiko Shirayama Osamu Saitoh Nobuo Anzai Shin-Ichi Niwa 《Psychiatry and clinical neurosciences》1990,44(4):667-679
Abstract: Fifteen psychiatric cases are reported who were clinically diagnosed as schizophrenic, affective disorders, or neurotic, but resisted standard medication regimens, all showing irregular β activities on EEGs. The cases tended to display symptoms in common, such as dysphoria, emotional instability or frequent physical complaints. These characteristic symptoms share something mutually with the symptoms shown in some epileptic patients or psychiatric patients with epileptic EEG abnormalities without clinical seizures. Antiepileptic drugs seemed more specifically effective to the above symptoms. More than half of these cases showed improvement on EEG findings such as a decrease in irregular β activities and an increase in rhythmicity or regularity of α activities along with clinical improvement with the administration of adjunctive antiepileptic drugs. These results suggest that the adjunctive administration of antiepileptic drugs to patients with irregular β activities on EEGs is clinically useful and an EEG examination has much value in psychiatric practice to find the criteria of drug therapy. 相似文献
79.
Yasuyuki Taki Benjamin Thyreau Shigeo Kinomura Kazunori Sato Ryoi Goto Kai Wu Ryuta Kawashima Hiroshi Fukuda 《Human brain mapping》2013,34(9):2292-2301
The aim of this study was to analyze correlations among the annual rate of gray matter volume change, age, gender, and cerebrovascular risk factors in 381 healthy community‐dwelling subjects with a large age range by applying a longitudinal design over 6 years using brain magnetic resonance images (MRIs). Brain MRI data were processed with voxel‐based morphometry using a custom template by applying diffeomorphic anatomical registration using the exponentiated lie algebra procedure. The annual rate of regional gray matter volume change showed significant positive correlations with age in several regions, including the bilateral temporal pole, caudate nucleus, ventral and dorsolateral prefrontal cortices, insula, hippocampus, and temporoparietal cortex, whereas significant negative correlations with age were observed in several regions including the bilateral cingulate gyri and anterior lobe of the cerebellum. Additionally, a significant age‐by‐gender interaction was found for the annual rate of regional gray matter volume change in the bilateral hippocampus. No significant correlations were observed between the annual rate of regional gray matter volume change and body mass index or systolic blood pressure. A significant positive correlation between the annual rate of gray matter volume change and age indicates that the region shows not linear but accelerated gray matter loss with age. Therefore, evaluating the annual rate of the gray matter volume change with age in healthy subjects is important in understanding how gray matter volume changes with aging in each brain region and in anticipating what cognitive functions are likely to show accelerated decline with aging. Hum Brain Mapp 34:2292–2301, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
80.
Nobuhiro Ohtake Youichiro Nakai Masahiro Yamamoto Atsushi Ishige Hiroshi Sasaki Kazunori Fukuda Seiji Hayashi Satoshi Hayakawa 《International immunopharmacology》2002,2(2-3):357-366
Shosaiko-to (SST), a Chinese/Japanese traditional herbal medicine, has recently been demonstrated to increase lung interleukin-6 (IL-6) levels and to ameliorate pulmonary disorders in BALB/c mice (BALB). In the present study, we examined the effects of SST on lung cytokine levels and lipopolysaccharide (LPS)-induced lung injury in C57BL/6 mice (B6), which are known to show different immune responses from BALB due to the difference in genetic backgrounds. In B6, in contrast with BALB, SST decreased lung IL-6 levels and exacerbated LPS-induced lung injury. Investigation of the active components of SST suggested that multiple ingredients were supposed to be responsible for IL-6-attenuating activity in vivo. Further, we examined the effect of metabolites of major ingredients of SST on IL-6 production from lung immune cells in vitro. Saikogenin D and oroxylin A attenuated IL-6 production in LPS-stimulated alveolar macrophages of B6 more than in that of BALB. Liquiritigenin, which was previously reported to enhance IL-6 production in anti-CD3 monoclonal antibody-stimulated lung mononuclear cells of BALB, showed no effect on that of B6. These findings suggest that SST may have different, possibly even opposite, effects on lung immunity in hosts with different genetic backgrounds. 相似文献