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We examined the mutant protein of mitochondrial acetoacetyl-CoA thiolase (mutant T2) in fibroblasts from a Japanese boy with 3-ketothiolase deficiency. The molecular size of the mutant T2 protein, determined by pulse labeling and SDS/PAGE, was intermediate between the mature subunit and the precursor of T2. To characterize the mutant T2 protein, pulse-labeling and rhodamine 6G inhibition of mitochondrial transport in fibroblasts, cell-free translation experiments, and family studies by thiolase assay, immunoblotting, and pulse-labeling were carried out. The mutant T2 was detectable as early as a 10-min pulse. The probable precursor of the mutant T2 was not detectable in either the rhodamine 6G inhibition or cell-free translation experiments. In the parents, the K+ ion dependency of acetoacetyl-CoA thiolase activity was low and the T2 bands in immunoblots were faint. It would thus appear that the parents are heterozygotes of this disease. In pulse-labeling, only a band for the mutant T2 was detected in the patient and a single band for the normal mature subunit of T2 in the father; both bands were detected in the mother. These findings suggested that the mutant T2 in the patient was inherited from the mother, and that the expression of another mutant allele of the father may be either abolished or scanty.  相似文献   
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The uptake of NM394, a new quinolone, by and its subsequent elution from human polymorphonuclear leukocytes were studied and compared with those of ofloxacin and ciprofloxacin. The kinetics of the uptake of NM394 was similar to that of ciprofloxacin. The maximum intracellular-to-extracellular concentration ratio was 12.3, compared with 8.6 for ciprofloxacin and 4.9 for ofloxacin at the extracellular concentration of 20 micrograms/ml. The elution of NM394 from human polymorphonuclear leukocytes occurs relatively slowly; 5 min after the removal of extracellular NM394, nearly 100% still remained in polymorphonuclear leukocytes, compared with ofloxacin, which was so rapidly eluted that only 12% remained. The uptake of NM394 was significantly decreased at 4 degrees C and by the presence of NaCN but was not affected by the presence of L-glycine, L-leucine, L-serine, adenosine, or NaF. NM394 showed intracellular activity at a concentration of 0.1 microgram/ml that significantly reduced the number of phagocytosed Pseudomonas aeruginosa cells with 2 h of incubation. These results suggest that uptake of NM394 by human polymorphonuclear leukocytes occurs via an active transport system differing from that of ofloxacin, whose uptake is affected by the presence of L-glycine and L-leucine, and that once accumulated, NM394 remains intracellularly active and participates in protection against bacterial infection.  相似文献   
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Aim: We have never known any epidemiological study of Arima syndrome since it was first described in 1971. To investigate the number of Arima syndrome patients and clarify the clinical differences between Arima syndrome and Joubert syndrome, we performed the first nationwide survey of Arima syndrome, and herein report its results. Furthermore, we revised the diagnostic criteria for Arima syndrome. Methods: As a primary survey, we sent out self-administered questionnaires to most of the Japanese hospitals with a pediatric clinic, and facilities for persons with severe motor and intellectual disabilities, inquiring as to the number of patients having symptoms of Arima syndrome, including severe psychomotor delay, agenesis or hypoplasia of cerebellar vermis, renal dysfunction, visual dysfunction and with or without ptosis-like appearance. Next, as the second survey, we sent out detailed clinical questionnaires to the institutes having patients with two or more typical symptoms. Results: The response rate of the primary survey was 72.7% of hospitals with pediatric clinic, 63.5% of national hospitals and 66.7% of municipal and private facilities. The number of patients with 5 typical symptoms was 13 and that with 2–4 symptoms was 32. The response rate of the secondary survey was 52% (23 patients). After reviewing clinical features of 23 patients, we identified 7 Arima syndrome patients and 16 Joubert syndrome patients. Progressive renal dysfunction was noticed in all Arima syndrome patients, but in 33% of those with Joubert syndrome. Conclusion: It is sometimes difficult to distinguish Arima syndrome from Joubert syndrome. Some clinicians described a patient with Joubert syndrome and its complications of visual dysfunction and renal dysfunction, whose current diagnosis was Arima syndrome. Thus, the diagnosis of the two syndromes may be confused. Here, we revised the diagnostic criteria for Arima syndrome.  相似文献   
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Elimination of granule cells (GCs) in the olfactory bulb (OB) is not a continual event but is promoted during a short time window in the postprandial period, typically with postprandial sleep. However, the neuronal mechanisms for the enhanced GC elimination during the postprandial period are not understood. Here, we addressed the question of whether top‐down inputs of centrifugal axons from the olfactory cortex (OC) during the postprandial period are involved in the enhanced GC elimination in the OB. Electrical stimulation of centrifugal axons from the OC of anesthetized mice increased GC apoptosis. Furthermore, pharmacological suppression of top‐down inputs from the OC to the OB during the postprandial period of freely behaving mice by γ‐aminobutyric acid (GABA)A receptor agonist injection in the OC significantly decreased GC apoptosis. Remarkable apoptotic GC elimination in the sensory‐deprived OB was also suppressed by pharmacological blockade of top‐down inputs. These results indicate that top‐down inputs from the OC to the OB during the postprandial period are the crucial signal promoting GC elimination, and suggest that the life and death decision of GCs in the OB is determined by the interplay between bottom‐up sensory inputs from the external world and top‐down inputs from the OC.  相似文献   
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Background

The importance of Notch signaling in colorectal cancer (CRC) tumorigenesis has been recently recognized. However, the significance of Notch3 expression and its association with Notch1 expression in CRC is unclear. In the present study, we investigated Notch1 and Notch3 expression in Stage II and III CRC to assess their association with clinicopathological characteristics.

Methods

The protein expression of Notch1 and Notch3 was examined using immunohistochemistry in 305 CRC specimens. Nuclear expression of Notch1 and Notch3 and their associations with clinicopathological characteristics and distant relapse-free survival (dRFS) were evaluated.

Results

Nuclear Notch1 was overexpressed in 37 % of specimen, and nuclear Notch3 in 38 %. Nuclear Notch3 expression correlated with tumor differentiation status (P = 0.0099). Nuclear expression of Notch1 and Notch3 was associated with tumor recurrence (P = 0.0311 and P = 0.0053, respectively). In multivariate analysis, nuclear Notch3 expression [hazard ratio (HR) = 1.71; 95 % confidence interval (CI), 1.06–2.78; P = 0.0271), lymph node metastasis, and venous involvement were independently correlated with dRFS. In subgroup analysis, nuclear Notch3 expression was strongly associated with dRFS in Stage II CRC (HR = 3.47; 95 % CI 1.44–9.22; P = 0.0055). Both nuclear Notch1 and Notch3 were positive in 67 specimens (22 %) and both were negative in 144 specimens (47 %). Coexpression of nuclear Notch1 and Notch3 had an additive effect toward poorer dRFS compared with a negative subtype (HR = 2.48; 95 % CI, 1.41–4.40; P = 0.0019).

Conclusions

Nuclear Notch3 expression might be a novel predictive marker for recurrence in Stage II and III CRC.  相似文献   
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Objective

Carotid artery stenting (CAS) is a well-accepted treatment for atherosclerotic stenosis of carotid arteries. Since the occurrence of distal embolization with CAS is still a major concern embolus protection devices (EPD) are usually employed during the procedure. We examined two types of embolus protection filters (Angioguard XP (AG); Filterwire EZ (FW)) and evaluated the function. Thus, the filter was examined postoperatively and the cause of intraoperative flow impairment was evaluated.

Materials and methods

CAS was performed for 54 patients with carotid artery stenosis (55 lesions: 25 AG; 27 FW; 3 others). After completing CAS the filter membrane was stained with hematoxylin-eosin (HE) solution and removed from the filter strut. Once mounted on a glass slide the filter was evaluated under a microscope. The area occupied with debris was measured and the relationship to intraoperative flow impairment was evaluated. Furthermore, the relationship between perioperative ischemic complications and intraoperative flow impairment was statistically analyzed.

Results

Microscopic observation of the slide revealed the pore density of the FW was 1.5 times higher than that of the AG and the filter area of the FW was 2.5 times wider than than the AG. HE staining facilitated characterization of the debris composition. The area occupied with debris was significantly more in the AG (0.241?±0.13 cm2) than in the FW (0.129?±0.093 cm2). Thus, fibrin was significantly more precipitated in the AG. Flow impairment occurred in 6 AG cases (24.0 %) and 4 FW cases (14.8 %). It was induced by filter obstruction in the AG and by vasospasms in the FW. Three cases treated with AG (12.0 %) were complicated with cerebral infarction and all of them were related to flow impairment. One FW case (3.7 %) was complicated with cerebral infarction in presence of preserved flow throughout the intervention.

Conclusion

Filter function is different according to each design. The cause of flow impairment was attributable to filter obstruction in the AG group and to vasospasms in the FW group. Filter obstruction tends to result in cerebral infarction.  相似文献   
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