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61.
1 alpha,25-Dihydroxyvitamin D3 [1 alpha,25(OH)2D3], a hormonally active form of vitamin D3, has been shown to modulate cell differentiation and tumor promotion. This report demonstrates that mRNA of the metallothionein (MT) gene was induced by 1 alpha,25(OH)2D3 in cultured epidermal keratinocytes and also in liver, kidney, and skin tissues when 1 alpha-hydroxyvitamin D3, a synthetic precursor of 1 alpha,25(OH)2D3, was applied in vivo. Exposure of FRSK cells, a cell line derived from fetal rat skin keratinocytes, to 1 alpha,25(OH)2D3 at 5 ng/ml (12 nM) increased MT mRNA to almost the same extent as that induced by 10 microM dexamethasone or 1 microM CdCl2. This increase in the level of MT mRNA was evident within 2 hr and was maximal 12-24 hr after the addition of 1 alpha,25(OH)2D3. The induction was dose-dependent with concentrations of 1 alpha,25(OH)2D3 from 0.05 to 5.0 ng/ml. Amounts of MT increased with the increase of MT mRNA induced by 1 alpha,25(OH)2D3. Of the derivatives of vitamin D3 tested, only 1 alpha,25(OH)2D3 caused marked induction. Treatment with cycloheximide did not inhibit MT mRNA induction by 1 alpha,25(OH)2D3. 1 alpha,25(OH)2D3 induced MT mRNA in primary cultures of mouse epidermal keratinocytes but not in IAR-20, a liver cell line. 1 alpha,25(OH)2D3 had a similar effect in vivo: oral administration of 1 alpha-hydroxyvitamin D3 to mice resulted in increased levels of MT mRNA in the liver, kidney, and skin 24 hr later. Increase in the level of MT mRNA may be relevant to some biological actions of 1 alpha,25(OH)2D3.  相似文献   
62.
We report a female patient who presented with intractable epileptic seizures, profound developmental delay since early infancy, and hyperkinetic movements with hand stereotypies. The patient initially developed focal seizures with multiple foci at 3 months of age. Thereafter, the seizures evolved to frequent episodes of hyperthermia‐induced status epilepticus. A novel de novo SCN1A mutation was identified by whole‐exome sequence analysis. This case demonstrates that SCN1A mutations may cause movement disorders as an atypical phenotype and the case history of this patient may expand our understanding of the clinical spectrum of SCN1A‐associated epileptic encephalopathy. [Published with video sequences]  相似文献   
63.
We present a case of a patient whose L1CAM gene in X‐chromosome has a C924T transition. Her first son's ventriculomegaly was prenatally detected. A mature infant was born, his head circumference was large, and thumbs were bilaterally adducted. X‐linked hydrocephalus (XLH) was suspected. The DNA examination revealed that both her and boy's LICAM gene had a C924T transition. She became pregnant 5 years later and amniocentesis was performed. The results of cytogenetic analysis revealed that the fetus was female. She continued her pregnancy and delivered a healthy girl. She again became pregnant 3 years later. The chromosomal analysis revealed that the fetus was male. Fetal DNA analysis determined that the fetus had the inherited mutation. She chose to terminate the pregnancy. A C924T mutation can be disease causing for XLH, and the detection of this mutation would aid in genetic counseling for the prenatal diagnosis of XLH.  相似文献   
64.
65.
BACKGROUND: DISC1 has been suggested as a causative gene for psychoses in a large Scottish family. We recently identified FEZ1 as an interacting partner for DISC1. To investigate the role of FEZ1 in schizophrenia and bipolar disorder, case-control association analyses were conducted in Japanese cohorts. METHODS: We performed a mutation screen of the FEZ1 gene and detected 15 polymorphisms. Additional data on informative polymorphisms were obtained from public databases. Eight single nucleotide polymorphisms (SNPs) were analyzed in 119 bipolar disorder and 360 schizophrenic patients and age- and gender-matched control subjects. All genotypes were determined with the TaqMan assay, and selected samples were confirmed by sequencing. RESULTS: The two adjacent polymorphisms displayed a nominally significant association with schizophrenia (IVS2+ 1587G>A, p = .014; 396T相似文献   
66.
ObjectivePatients with pathogenic cyclin-dependent kinase-like-5 gene (CDKL5) variants are designated CDKL5 deficiency disorder (CDD). This study aimed to delineate the clinical characteristics of Japanese patients with CDD and elucidate possible appropriate treatments.MethodsWe recruited patients with pathogenic or likely pathogenic CDKL5 variants from a cohort of approximately 1,100 Japanese patients with developmental and epileptic encephalopathies, who underwent genetic analysis. We retrospectively reviewed clinical, electroencephalogram, neuroimaging, and genetic information.ResultsWe identified 29 patients (21 females, eight males). All patients showed severe developmental delay, especially in males. Involuntary movements were observed in 15 patients. No antiepileptic drugs (AEDs) achieved seizure freedom by monotherapy. AEDs achieving ≥ 50% reduction in seizure frequency were sodium valproate in two patients, vigabatrin in one, and lamotrigine in one. Seizure aggravation was observed during the use of lamotrigine, potassium bromide, and levetiracetam. Adrenocorticotrophic hormone (ACTH) was the most effective treatment. The ketogenic diet (KD), corpus callosotomy and vagus nerve stimulation did not improve seizure frequency in most patients, but KD was remarkably effective in one. The degree of brain atrophy on magnetic resonance imaging (MRI) reflected disease severity. Compared with females, males had lower levels of attained motor development and more severe cerebral atrophy on MRI.ConclusionOur patients showed more severe global developmental delay than those in previous studies and had intractable epilepsy, likely because previous studies had lower numbers of males. Further studies are needed to investigate appropriate therapy for CDD, such as AED polytherapy or combination treatment involving ACTH, KD, and AEDs.  相似文献   
67.
Disrupted-in-schizophrenia 1 (DISC1) is a gene disrupted by a (1;11) (q42.1;q14.3) translocation that segregates with major psychiatric disorders in a Scottish family. To investigate how DISC1 confers susceptibility to psychiatric disorders, we previously identified fasciculation and elongation protein zeta-1 and Kendrin as DISC1-interacting molecules in a yeast two-hybrid screen of a human brain complementary DNA library. Here, we have further identified a novel DISC1-interacting protein, termed DISC1-Binding Zinc-finger protein (DBZ), which has a predicted C(2)H(2)-type zinc-finger motif and coiled-coil domains. DBZ was co-immunoprecipitated with DISC1 in lysates of PC12 cells and rat brain tissue. The domain of DISC1 interacting with DBZ was close to the translocation breakpoint in the DISC1 gene. DBZ messenger RNA (mRNA) was expressed in human brains, but not in peripheral tissues. In situ hybridization revealed high expression of DBZ mRNA in the hippocampus, olfactory tubercle, cerebral cortex and striatum in rats. Because this pattern of localization was similar to that of the pituitary adenylate cyclase (PAC(1)) receptor for pituitary adenylate cyclase-activating polypeptide (PACAP), which has recently been implicated in neuropsychological functions, we examined whether DISC1/DBZ interaction was involved in the PACAP signaling pathway. PACAP upregulated DISC1 expression and markedly reduced the association between DISC1 and DBZ in PC12 cells. A DISC1-binding domain of DBZ reduced the neurite length in PC12 cells after PACAP stimulation and in primary cultured hippocampal neurons. The present results provide some new molecular insights into the mechanisms of neuronal development and neuropsychiatric disorders.  相似文献   
68.
The combined effects of bracing, axial compression and inversion rotation on the ankle-subtalar complexes were evaluated. Ex vivo tests under the load-controlled condition were performed on six cadaver ankle specimens using a six degree-of-freedom fixture. Inversion rotation was measured while subjecting the ankle-subtalar complex to a 2.5 N-m inversion moment and a combination of the testing variables (brace type, no brace, 178 N axial compression load, no compression load, 0° and 20° of plantar flexion) for a total of 16 tests per specimen. Three commercially available braces (two semirigid types and one lace up type) were evaluated. An axial compression load significantly decreased ankle-subtalar motion in unbraced ankles for the tested inversion moment. The contribution of bracing to stabilization of the ankle was smaller in the axial loading condition than in the no axial loading condition. The semirigid braces had greater stabilizing effects in response to the inversion moment than the lace up brace. Stabilizing effects of bracing were significantly greater in 20° of plantar flexion than in 0° of plantar flexion. The most common mechanism for an ankle sprain injury is inversion rotation on a weight-bearing ankle. Therefore, we should not overestimate stabilizing effects of bracing from evaluations of bracing without axial compression loading.  相似文献   
69.
Thymus atrophy is induced by a variety of chemicals, including environmental contaminants and is used as a sensitive index to detect their adverse effects on lymphocytes. In the present study we adopted a toxicogenomics approach to identify the pathways that mediate the atrophy induced by arsenite. We also analyzed gene expression changes observed in the course of thymus atrophy by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), dexamethasone (DEX), and estradiol (E2), to determine whether arsenite induces atrophy by activating an arsenite-specific pathway or the same pathways as other chemicals. These compounds were intraperitoneally administered to C57BL/6 mice at doses that reduce thymus weight by approximately 30% within 3 days, and gene expression changes in the thymus 24 h after the administration were analyzed by using microarrays and real-time PCR. The microarray analysis showed that arsenite specifically downregulates a variety of E2F target genes that are involved in cell cycle progression. The same genes were also downregulated when mouse B-cell lymphoma A20 cells were exposed to arsenite. Arsenite exposure of the A20 cells was confirmed to induce cell cycle arrest, mainly in the G(1) phase, and reduce cell number. Cell cycle arrest in the G(1) phase was also confirmed to occur in the thymocytes of the arsenite-exposed mice. These results indicate that arsenite induces thymus atrophy through E2F-dependent cell cycle arrest. The results of this study also show that analysis of gene expression in thymuses is a useful method of obtaining clues to the pathways that mediate the effects of atrophy-inducing chemicals.  相似文献   
70.
The localization and fine structure of calcitonin gene-related peptide (CGRP)-like immunoreactive (CGRPI) fibres in the guinea pig cochlea were examined using immunohistochemistry. Numerous CGRPI fibres were located in the inner spiral bundle corresponding to the lateral system of the olivocochlear bundle. Immunoelectron microscopic analysis demonstrated that the CGRPI fibres belonged to the efferent terminals and some of them made synaptic contacts with peripheral neurites of the auditory nerve. These findings suggested that the olivocochlear CGRP neuron system influenced the neural activity of the auditory nerve, which conveys auditory information from the cochlea to the central nervous system.  相似文献   
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