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21.
M U  L Shen  T Oshida  J Miyauchi  M Yamada  T Miyashita 《Leukemia》2004,18(11):1850-1856
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Objective: The molecular defect in patients with X-linked mixed deafness showing a perilymphatic gusher at stapedectomy (DFN3) has been attributed to mutations in the POU3F4 gene. This study aimed to clarify an allelic variant of this gene. Study Design: This was a genetic study of a single Japanese family with DFN3. Methods: Products of a polymerase chain reaction (PCR) were subjected to single-strand conformation polymorphism (SSCP) analysis. Direct sequencing of PCR products from patients and carriers showing SSCP variants was performed using the fluorescent dideoxy termination method and a sequencer. Results: Sequencing of the PCR product revealed a 6-base deletion (TTCAAA) at nucleotides 601 to 606, resulting in a two-amino-acid deletion in the POU3F4 protein, (phenylalanine and lysine at amino acid residues 201 and 202). The deletion was adjacent to the site of a nonsense mutation previously described. Conclusion: Microdeletions at a previously undescribed location account for some clinically important POU3F4 mutations. Laryngoscope, 108:1544–1547, 1998  相似文献   
24.
Social skill deficits in schizophrenia profoundly affect patients' life-long outcome, although the profile of the underlying cognitive dysfunction still remains a matter of debate. In the present study, we investigated the relationship between social skills and event-related potentials (ERPs) in an auditory selective attention task, in addition to the neurocognitive indices obtained from the degraded-stimulus continuous performance test (CPT) and clinical indices, such as Brief Psychiatric Rating Scale (BRPS) and global assessment of function (GAF) scores. Social skills were assessed using a Japanese version of the structured role play test. Fourteen persons with schizophrenia participated in the study. Non-verbal skills showed a positive correlation with GAF, the performance level, N1 and N2b amplitude in the ERP task, and hit rate in the CPT, and a negative correlation with reaction time in the CPT. Verbal communication skills showed a positive correlation with GAF, the performance level and N2b amplitude in the ERP task, and hit rate in the CPT, and a negative correlation with reaction time in the CPT. Processing skills showed a positive correlation with the performance level and N1 amplitude in the ERP task and a negative correlation with reaction time in the CPT. These findings suggested that the social skill deficits of persons with schizophrenia were related to the vigilance level and controlled stimulus detection processing.  相似文献   
25.
Using the characteristic morphological changes of mammalian cells, we screened novel antimitotic substances and found that a strain of Streptomyces sp. No.9885 produced FR182877. This substance was isolated from the culture broth by ethyl acetate extraction, silica gel column chromatography and ODS column chromatography. Structural studies on FR182877 suggested that it had a unique hexacyclic structure encompassing its highly strained double bond. FR182877 exhibited potent antitumor activities against murine ascitic tumor and solid tumor in vivo.  相似文献   
26.
Protein kinase C delta (PKCδ) is a multifunctional PKC family member and has been implicated in many types of cancers, including liver cancer. Recently, we have reported that PKCδ is secreted from liver cancer cells, and involved in cell proliferation and tumor growth. However, it remains unclear whether the extracellular PKCδ directly regulates cell surface growth factor receptors. Here, we identify epidermal growth factor receptor (EGFR) as a novel interacting protein of the cell surface PKCδ in liver cancer cells. Imaging studies showed that secreted PKCδ interacted with EGFR‐expressing cells in both autocrine and paracrine manners. Biochemical analysis revealed that PKCδ bound to the extracellular domain of EGFR. We further found that a part of the amino acid sequence on the C‐terminal region of PKCδ was similar to the putative EGFR binding site of EGF. In this regard, the point mutant of PKCδ in the binding site lacked the ability to bind to the extracellular domain of EGFR. Upon an extracellular PKCδ‐EGFR association, ERK1/2 activation, downstream of EGFR signaling, was apparently induced in liver cancer cells. This study indicates that extracellular PKCδ behaves as a growth factor and provides a molecular basis for extracellular PKCδ‐targeting therapy for liver cancer.  相似文献   
27.
Purpose: The purpose of the present study was to evaluate contrast enhancement of the infundibular recess in the normal state using heavily T2-weighted 3D fluid-attenuated inversion recovery (FLAIR) (HT2-FLAIR).Methods: Twenty-six patients were retrospectively recruited. We subjectively assessed overall contrast enhancement of the infundibular recess between postcontrast, 4-hour (4-h) delayed postcontrast, and precontrast HT2-FLAIR images. We also objectively conducted chronological and spatial comparisons by measuring the signal intensity (SI) ratio (SIR). Chronological comparisons were performed by comparing SI of the infundibular recess/SI of the midbrain (SIRIR-MB). Spatial comparisons were conducted by comparing SI on postcontrast HT2-FLAIR/SI on precontrast HT2-FLAIR (SIRPost-Pre) of the infundibular recess with that of other cerebrospinal fluid (CSF) spaces, including the superior part of the third ventricle, lateral ventricles, fourth ventricle, and interpeduncular cistern.Results: In the subjective analysis, all cases showed contrast enhancement of the infundibular recess on both postcontrast and 4-h delayed postcontrast HT2-FLAIR, and showed weaker contrast enhancement of the infundibular recess on 4-h delayed postcontrast HT2-FLAIR than on postcontrast HT2-FLAIR. In the objective analysis, SIRIR-MB was the highest on postcontrast images, followed by 4-h delayed postcontrast images. SIRPost-Pre was significantly higher in the infundibular recess than in the other CSF spaces.Conclusion: The present results demonstrated that the infundibular recess was enhanced on HT2-FLAIR after an intravenous gadolinium injection. The infundibular recess may be a potential source of the leakage of intravenously administered gadolinium into the CSF.  相似文献   
28.
Mid-aortic syndrome (MAS) is a rare vascular disorder that causes refractory hypertension. A 76-year-old woman was hospitalized for acute heart failure (HF) with drug-resistant hypertension; other comorbidities included epigastric artery rupture, old myocardial infarction, an intraventricular thrombus, and a cerebral artery aneurysm. Angiography revealed severe narrowing of the descending aorta, which led to the diagnosis of MAS. Although intensive medical treatment improved her HF, optimal blood pressure (BP) could not be achieved. Percutaneous coronary intervention and surgical bypass for diseased aorta was then performed in two stages, resulting in the achievement of optimal BP and alleviation of HF.  相似文献   
29.

Background

Increased bone mineral density (BMD) has been reported in patients with postsurgical permanent hypoparathyroidism. Hypoparathyroidism may attenuate the high-turnover bone loss in postmenopausal women. We reported previously that patients who had transient hypoparathyroidism postoperatively were at subclinical hypoparathyroid (hP) status even 5 years after surgery. We hypothesized that patients with transient hypoparathyroidism (ThP) may have altered BMD.

Methods

A total of 140 women who underwent total thyroidectomy had BMD measurements of the lumbar spine, femoral neck, and radius 3 years after surgery. At surgery, 99 patients were ≥50 years and 41 were <50 years. They were divided into three groups according to their postoperative parathyroid function: There were 80 patients in the no hP (NhP) group, 54 in the ThP group, and 6 in the permanent hP (PhP) group.

Results

Among the 99 patients aged ≥50 years, 36 ThP patients had median Z scores of the BMD in all three areas (lumbar spine, femoral neck, radius) that were significantly higher (by 1.083, 0.533, and 1.047, respectively) than those in the 60 NhP patients aged ≥50 years. The BMDs in the three PhP patients ≥50 years were higher than those in the NhP and ThP patients, but the difference did not reach significance except for in the femoral neck. Multivariate logistic regression analyses showed that Z scores > 0 were significantly associated only with the presence of ThP postoperatively. In the patients <50 years, the BMD values were not significantly different among the three groups except at the radius in PhP patients, which was significantly lower than those of the other patients.

Conclusions

We found that ThP was associated with increased BMD in postmenopausal women. This may be due to attenuation of the high-turnover bone loss in postmenopausal women.  相似文献   
30.

Background

Endoscopic ultrasound (EUS)-guided drainage is widely used to manage pancreatic pseudocysts. Several studies have reported the use of EUS-guided drainage for pancreatic fistula and stasis of pancreatic juice caused by stricture of the pancreatic duct after pancreatic resection.

Methods

At the authors’ hospital, 262 patients underwent surgery involving pancreatic resection from April 2005 to March 2010. In 90 of these patients (34%), a grade B or C postoperative pancreatic fistula developed that required additional treatment. The authors performed EUS-guided transmural drainage (EUS-TD) for six patients (2.1%) with a pancreatic fistula or dilation of the main pancreatic duct visible by EUS. Percutaneous drainage was provided for 18 patients (6.8%). The success rates for EUS-TD and percutaneous drainage were compared in a retrospective analysis.

Results

In all six cases, EUS-TD was performed successfully without complications. Five of the six patients were successfully treated with only one trial of EUS-TD. The final technical success rate was 100% for both EUS-TD and percutaneous drainage. Both the short- and long-term clinical success rates for EUS-TD were 100% and those for percutaneous drainage were 61.1 and 83%, respectively. The differences in these rates were not significant (short-term success, P?=?0.091 vs. long-term success, P?=?0.403). However, the time to clinical success was significantly shorter with EUS-TD (5.8?days) than with percutaneous drainage (30.4?days; P?=?0.0013) in the current series.

Conclusions

The EUS-TD approach appears to be a safe and technically feasible alternative to percutaneous drainage and may be considered as first-line therapy for pancreatic fistulas visible by EUS.  相似文献   
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