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101.
Midkine (MK) is a heparin-binding growth factor that occurs as a product of the retinoic acid-inducible gene. Alteration of MK expression in ischemic brain lesions was examined in humans immunohistochemically in nine patients and in two control subjects without neurological disorders. Some neurons were MK-immunopositive, but no evident MK-immunoreactivity was observed in astrocytes in brains of control subjects. In the ischemic lesions, significant elevation of MK-immunoreactivity in the astrocytes and depletion of the reactivity in neurons were seen, especially in the early period, where edema and eosinophilic neurons were prominent. On the other hand, MK-immunoreactivity was not observed in hypertrophic and fibrillary astrocytes in the later period. These findings suggest that the MK in astrocytes play some role in the repair process in the early period of the ischemic brain lesions in humans.  相似文献   
102.
OBJECTIVE: To examine the responsiveness of measures adopted in the effort-reward imbalance (ERI) questionnaire to organizational changes. METHOD: For the employees who had been affected by restructuring of their company due to the economic hardship, two consecutive questionnaire surveys were conducted over a specific period. A total of 544 full-time employees responded to both surveys. Changes in four summary measures from the situation-specific model component and the person-specific component, and items/subscales that constitute the questionnaire were evaluated. RESULTS: The summary measures on psychological deterioration in the total study population. The deterioration was prevalent in those employees who had presumably experienced the effects of stressful organizational changes related to the restructuring, while improvement in the summary measures was observed for those employees who were promoted during the period. On the whole, the measures for the items of the situation-specific component and subscales for the personal component changed in the expected direction. With regard to ERI, potentially stronger effects of multiple organizational changes on employees were indicated. CONCLUSION: Measurements of ERI at work are valid in terms of responsiveness to organizational changes.  相似文献   
103.
The immunosuppressive drug cyclosporine A (CsA) has been used in both organ transplantation and the treatment of autoimmune disorders. However, the drug causes adverse effects in the kidney, liver and nervous system, characterized by cellular loss in the affected area. Apoptosis has been shown to play a role in CsA-induced cytotoxicity. Because permeabilization of the mitochondrial membrane is a common criterion in most apoptotic settings in vertebrate cells, here we evaluated whether CsA causes loss of mitochondrial function in the pathway leading to cellular cytotoxicity. We found that CsA caused a concentration- and time-dependent loss of cell viability in the U937 cell line. Treatment of cells at a dose of 10 microM CsA resulted in G0/G1 arrest with a concurrent decrease in the number of cells in the S and G2/M phases of the cell cycle. In mechanistic studies related to the loss of viability, treating cells with 10 microM CsA for 24 h resulted in both DNA fragmentation and an increase of annexin-V-positive cells. CsA treatment also increased activity of the cysteine protease caspase-3, decreased the mitochondrial membrane potential and induced the release of cytochrome c into the cytosol. Furthermore, CsA treatment increased the number of cells in the sub-G0/G1 peak, indicative of a reduction in DNA, although this increase was not observed when cells were pre-treated with a broad caspase inhibitor. In the study, we also found that a higher dose of CsA induces LDH release when the cells were incubated for a longer period. Taken together, these data suggest that the mode of cell death induced by CsA is dose- and time-dependent. Short-term incubation with lower doses of CsA arrests cell growth; this arrest overlaps with the occurrence of apoptosis and then with necrosis after longer treatment periods with higher doses of CsA.  相似文献   
104.
Umbilical ulceration is an extremely rare complication in the perinatal period. We encountered a case of intestinal atresia complicated by massive intrauterine hemorrhage due to the umbilical cord ulceration. This is the fifth reported case demonstrating an association between the umbilical cord ulceration and intestinal atresia.  相似文献   
105.
In some patients with non-islet-cell tumor hypoglycemia (NICTH), a high molecular weight form of IGF-II (big IGF-II) derived from tumors is present in the circulation and might be associated with recurrent hypoglycemia. In this study, in order to survey the clinical characteristics of patients with IGF-II producing NICTH, we analyzed the medical records of 78 patients with NICTH (M/F 44/34, age 62+/-1.8, range; 9-86 years.) whose serum contained a large amount of big IGF-II. Hepatocellular carcinoma and gastric carcinoma were the most common causes of NICTH. The diameters of the tumors were more than 10 cm in 70% of the patients. Basal immunoreactive insulin (IRI) levels were less than 3 microU/dl in 79% of the patients. Hypoglycemic attack was the onset of disease in 31 of 65 cases (48%), but the tumor was revealed prior to the occurrence of hypoglycemia in 34 cases (52%). Twenty-five of 47 (53%) patients had decreased serum potassium levels. These data suggested that hypoinsulinemic hypoglycemia associated with the presence of a large tumor supports the diagnosis of IGF-II producing NICTH. Hypokalemia was associated with hypoglycemia in some patients. The BMI (21.4+/-0.6 kg/m2) and serum total protein levels (6.6+/-0.1g/dl) were preserved at the occurrence of first hypoglycemic attack suggesting that malnutrition might not be the main cause of hypoglycemia in most patients.  相似文献   
106.
Histone deacetylase (HDAC) 6 is a subtype of the HDAC family; it deacetylates alpha-tubulin and increases cell motility. Here, we investigate the impact of an alteration of HDAC6 expression in estrogen receptor alpha (ER)-positive breast cancer MCF-7 cells, as we identified that HDAC6 is a novel estrogen-regulated gene. MCF-7 treated with estradiol showed increased expression of HDAC6 mRNA and protein and a four-fold increase in cell motility in a migration assay. Cell motility was increased to the same degree by stably transfecting the HDAC6 expression vector into MCF-7 cells. In both cases, the cells changed in appearance from their original round shape to an axon-extended shape, like a neuronal cell. This HDAC6 accumulation caused the deacetylation of alpha-tubulin. Either the selective estrogen receptor modulator tamoxifen (TAM) or the pure antiestrogen ICI 182,780 prevented estradiol-induced HDAC6 accumulation and deacetylation of alpha-tubulin, leading to reduced cell motility. Tubacin, an inhibitory molecule that binds to the tubulin deacetylation domain of HDAC6, also prevented estradiol-stimulated cell migration. Finally, we evaluated HDAC6 protein expression in 139 consecutively archived human breast cancer tissues by immunohistochemical staining. The prognostic analyses for these patients revealed no significant differences based on HDAC6 expression. However, subset analysis of ER-positive patients who received adjuvant treatment with TAM (n = 67) showed a statistically significant difference in relapse-free survival and overall survival in favor of the HDAC6-positive group (P < 0.02 and P < 0.05, respectively). HDAC6 expression was an independent prognostic indicator by multivariate analysis (odds ratio = 2.82, P = 0.047). These results indicate the biological significance of HDAC6 regulation via estrogen signaling.  相似文献   
107.
108.
We administered zonisamide (ZNS) to patients with West syndrome in different titration protocols and compared their short-term therapeutic effects. We designed three protocols to raise the serum ZNS concentration (SZC): (1) increase the dose in three steps, from 3 to 10 mg/kg every 3 days, (2) increase the dose from 5 to 10 mg/kg over 3-7 days, and (3) start with 10 mg/kg and maintain this dosage for 2 weeks. The subjects were 23 infants with West syndrome, 8 of whom comprised the 1st group, 5 the 2nd group, and the remaining 10, the 3rd group. As a result, excellent and good effects were obtained in a total of seven patients (30.4%) and one patient, respectively (1/8 in the 1st step-up group, 3/5 in the 2nd step-up group, and 4/10 in the 3rd group). The maximum SZC was higher in the excellent and good effect groups (n=8; 32.0+/-8.0 microg/ml) than in the ineffective group (n=15; 22.4+/-8.2 microg/ml) (P<0.05). The period of time required for cessation of spasms appeared shorter in the 3rd group (n=4; mean=5.7 days) than in the 1st and 2nd groups (n=4; mean=10.3 days). There were few side effects except for transient hyperthermia and gastrointestinal symptoms. Our new protocol of starting with 10 mg/kg of ZNS can be introduced safely and make a therapeutic judgment feasible within 2 weeks.  相似文献   
109.
We report the first two Japanese children diagnosed with glucose transporter type 1 (GLUT1) deficiency syndrome. Both boys had been treated under the initial diagnosis of epilepsy and were reinvestigated for previously unexplainable hypoglycorrhachia. Myoclonic seizures developed at 4 months of age in Patient #1 (7 years old), and at 2 months of age in Patient #2 (11 years old), followed by cerebellar ataxia, spastic diplegia, and mental retardation. Both patients had hypoglycorrhachia, and the symptoms were more severe in the latter. CSF and serum glucose levels determined simultaneously showed a CSF/serum glucose ratio of below 0.4 in both patients. In mildly affected Patient #1, the postprandial waking EEG showed improvement in the background activity, as compared to that recorded after overnight fasting, while no significant changes were observed in severely affected Patient #2. In both patients, the functional GLUT1 defect was confirmed by 3-O-methyl-D-glucose uptake into erythrocytes. Molecular analyses identified heterozygous novel mutations in both patients, within exons 6 and 2 of the GLUT1 gene, respectively. The ketogenic diet was refused in Patient #1, but started in Patient #2 with significant clinical benefit. Fasting CSF analysis and pre-/postprandial EEG changes in children with epileptic seizures and unexplainable neurological deterioration help in diagnosing this potentially treatable disorder.  相似文献   
110.
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