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41.
Reiko Yoshida Yoshimitsu Fukushima Hirofumi Ohashi Masako Asoh Yukio Fukuyama 《Journal of human genetics》1993,38(4):437-444
Summary Two patients with the Costello syndrome are presented. One was a 7-year-old girl with a history of infantile hypotonia and feeding difficulties. The other was a 3 5/12-year-old boy with a history of neonatal sepsis and respiratory problems. Both had relative macrocephaly at birth, curly hair, large ear lobes, epicanthic folds, a low nasal bridge, thick lips, a short and wide nose, a short neck, a barrel chest, redundant skin, tight Achilles tendons, and pes equinovarus. Nasal papillomata, as described in Costello's two patients, were absent in both patients. Borochowitzet al. (1992) described five patients with what we interpreted as the Costello syndrome but without nasal papillomata. In view of these findings, nasal papillomata are not likely to be essential in the diagnosis of the Costello syndrome. 相似文献
42.
43.
Effects of nocturnal bright light on saliva melatonin, core body temperature and sleep propensity rhythms in human subjects 总被引:1,自引:0,他引:1
Kubota T Uchiyama M Suzuki H Shibui K Kim K Tan X Tagaya H Okawa M Inoue S 《Neuroscience research》2002,42(2):115-122
Nine healthy male volunteers (mean age of 24) participated in two experimental sessions of random crossover design: a bright light (5000 lux for 5 h from 00:00 to 05:00 h) session and a dim light (10 lux for 5 h from 00:00 to 05:00 h) session. Subsequently participants entered an ultra-short sleep-wake schedule for 26 h, in which a sleep-wake cycle consisting of 10-min sleep EEG recording on a bed and 20-min resting awake on a semi-upright chair were repeated. Saliva melatonin level and core body temperature was measured throughout the experiment. Bright light significantly delayed rhythms of melatonin secretion (01:58 h), core body temperature (01:12 h) and sleep propensity (02:00 h), compared as dim light session. Significant positive correlation was found between bright light-induced phase change in core body temperature and that in sleep propensity rhythm. Light-induced melatonin suppression significantly positively correlated with the phase change in core body temperature and that in sleep propensity rhythm. Assuming that light-induced melatonin suppression represents an acute impact of light on the circadian pacemaker, our results suggest that such an impact may be directly reflected in phase changes of sleep propensity and core body temperature rhythms rather than in melatonin rhythm. 相似文献
44.
Hidetoshi Taniguchi Ikuko Mohri Hitomi Okabe-Arahori Takahisa Kanekiyo Kuriko Kagitani-Shimono Kazuko Wada Yoshihiro Urade Masahiro Nakayama Keiichi Ozono Masako Taniike 《Neuroscience letters》2007
Lipocalin-type prostaglandin (PG) D synthase (L-PGDS) is up-regulated in oligodendrocytes (OLs) in mouse models for genetic neurological disorders including globoid cell leukodystrophy (twitcher) and GM1 and GM2 gangliosidoses and in the brain of patients with multiple sclerosis. Since L-PGDS-deficient twitcher mice undergo extensive neuronal death, we concluded that L-PGDS functions protectively against neuronal degeneration. In this study, we investigated whether L-PGDS is also up-regulated in acute and massive brain injury resulting from neonatal hypoxic-ischemic encephalopathy (HIE). Analysis of brains from human neonates who had died from HIE disclosed that the surviving neurons in the infarcted lesions expressed L-PGDS. Mouse models for neonatal HIE were made on postnatal day (PND) 7. Global infarction in the ipsilateral hemisphere was evident at 24 h after reoxygenation in this model. Intense L-PGDS immunoreactivity was already observed at 10 min after reoxygenation in apparently normal neurons in the cortex, and thereafter, in neurons adjacent to the infarcted area. Quantitative RT-PCR revealed that the L-PGDS mRNA level of the infarcted hemisphere was 33-fold higher than that of the sham-operated mouse brains at 1 h after reoxygenation and that it decreased to the normal level by 24 h thereafter. Furthermore, in both human and mouse brains, many of L-PGDS-positive cells were also immunoreactive for p53; and some of these expressed cleaved caspase-3. The expression of L-PGDS in degenerating neurons implies that L-PGDS functions as an early stress protein to protect against neuronal death in the HIE brain. 相似文献
45.
The distribution of acetylcholinesterase(AChE)-positive nerves in chicken pancreas demonstrated by light and electron microscopy 总被引:1,自引:0,他引:1
The distribution of acetylcholinesterase (AChE)-positive nerve fibers in the chicken pancreas was investigated with histochemical methods at the light and electron microscopic level. AChE-positive nerve bundles were found to run along the pancreaticoduodenal artery and their branches proceed into interlobular connective tissue, form a plexus around the interlobular secretory ducts and small arteries, and penetrate the exocrine parenchyma. Intrapancreatic ganglia showing a strong AChE activity were detected within the interlobular connective tissue or between acini. The exocrine pancreas was richly innervated with AChE-positive terminals which contained a few large dense-cored vesicles (about 100 nm in diameter) and many small clear vesicles (about 50 nm in diameter). Such terminals made contact with intercalated ductular cells and the smooth muscles of larger blood vessels. The endocrine pancreas was supplied with fewer nerves than the exocrine pancreas. A different distribution of AChE-positive fibers was noticed between A- and B-islets which were distinguished immunohistochemically. B- and D-cells were richly innervated by AChE-positive nerves, whereas A-cells, only poorly. These observations make clear that the cholinergic system relates to the regulation of both exocrine and endocrine tissues, except A-cells, in the chicken pancreas. 相似文献
46.
47.
In vivo labeling of amyloid with BF-108 总被引:3,自引:0,他引:3
Suemoto T Okamura N Shiomitsu T Suzuki M Shimadzu H Akatsu H Yamamoto T Kudo Y Sawada T 《Neuroscience research》2004,48(1):65-74
Detection of aggregated amyloid-beta (Abeta) with a non-invasive imaging modality such as positron emission tomography (PET) was suggested to be ideal for the diagnosis of Alzheimer's disease (AD) prior to the onset of clinical symptoms. We have been searching for imaging probe candidates with a high affinity for aggregated Abeta in vitro and in vivo and high lipophilicity, a characteristic that allows for the permeation of the blood-brain barrier (BBB). As analyzed by Thioflavin T (ThT) assay and octanol/water partition coefficient test (PC), 3-diethylamino-6-(2-fluoroethyl)ethylaminoacridine (BF-108) were found to have high affinity for Abeta aggregates in vitro and high lipophilicity. Intravenously administrated BF-108 labeled Abeta aggregates injected into the amygdala as observed under a fluorescence microscope, showing this compound's permeability of BBB and an ability to label Abeta in vivo. BF-108 also labeled neuritic senile plaques (SPs), neurofibrillary tangles, and amyloid-laden vessels in temporal and hippocampal sections from AD patients. Following intravenous administration of BF-108 to an APP23 transgenic (TG) mouse, in vivo labeling of endogenous plaques was seen in brain sections by fluorescence microscopy. These properties suggest the potential utility of BF-108 for in vivo imaging of AD pathology. 相似文献
48.
Fujihara N Tozuka M Yamauchi K Ueno I Urasawa N Ishikawa S Hirota-Kawadobora M Okumura N Hidaka H Katsuyama T 《Annals of clinical and laboratory science》2004,34(2):218-225
Factor XII Tenri (Y34C), a rare cross-reacting material (CRM)-negative factor XII deficiency, was identified in a 71-yr-old Japanese woman with angina pectoris. In the patient's plasma, factor XII activity and antigen levels were only 1.6% and 5.0%, respectively, of those seen in a normal subject. Immunoblot analysis showed that the secreted factor XII Tenri existed not only as a monomer (76 kDa), but also in complexes with apparent molecular weights of approximately 115, 140, 190, 215, and 225 kDa. After reduction with 2-mercaptoethanol, the factor XII Tenri contained in the complexes was completely converted to monomeric form on immunoblot patterns. It appeared that some of the secreted factor XII Tenri formed several types of disulfide-linked complexes, including a factor XII-alpha1-microglobulin complex, through a newly generated Cys residue. The monomeric form of factor XII Tenri, like normal factor XII, was degraded into 2 major fragments with molecular weights of approximately 45 kDa and 30 kDa following mixing with activated partial-thromboplastin-time measuring reagent (cephalin and ellagic acid), whereas the factor XII Tenri that formed the complexes was not. This indicates that the factor XII Tenri present in disulfide-linked complexes with other proteins (and itself) is not converted to active forms, suggesting that attached proteins obstruct or delay the activation of factor XII via an inhibition of its binding to a negatively charged surface in vitro. 相似文献
49.
Derivation and morphological characterization of mouse spermatogonial stem cell lines 总被引:9,自引:0,他引:9
Ogawa T Ohmura M Tamura Y Kita K Ohbo K Suda T Kubota Y 《Archives of histology and cytology》2004,67(4):297-306
Spermatogonial stem cells (SSCs), having yet to possess decisive markers, can only be detected retrospectively by transplantation assay. It was reported recently that mouse gonocytes collected from DBA/2 and ICR neonates propagated in vitro. This cultured germ cell, named the germline stem cell (GS cell), produced functional sperm to make progeny when transplanted into recipient mouse testes. Here we show that GS cell lines can be established not only from neonatal testes but also from the testis of adult mice. We also confirmed that GS cells once transplanted into a host testis can be recovered to resume in vitro expansion, indicating that they are convertible mutually with SSCs in adult testes. Confocal laser microscopic examination showed GS cells resemble undifferentiated spermatogonia in the adult testis. This unique cell line could be useful for research in germ cell biology and applicable as a new tool for the genetic engineering of animals. 相似文献
50.