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Medulloblastoma (MB) is a clinically and biologically heterogeneous group of tumors, and currently classified into four molecular subgroups (Wnt, Shh, Group 3 and Group 4). Intracellular signaling of the Wnt pathway has been divided into two classes: the “canonical” and the “non‐canonical” signaling pathway. The canonical signaling pathway is a well‐established, β‐catenin‐dependent signaling pathway in MB. In contrast, very little research about the non‐canonical WNT signaling pathway in MB exists. In order to identify the roles of Wnt‐5a and Ror2, two non‐canonical WNT pathway‐related genes, we studied 76 cases of MB with immunohistochemistry and quantitative real‐time PCR and correlated the results with clinicopathological and other molecular parameters and prognosis. Wnt5a and Ror2 were immunopositive in 20 (29.4%) and 35 (51.5%) of 68 cases, respectively. There were positive associations among protein expressions of Wnt5a, Ror2 and β‐catenin. Ror2 mRNA levels were well correlated with immunoexpression. Ror2 mRNA expression was significantly associated with CTNNB1 mutation. High Ror2 mRNA expression was an independent favorable prognostic factor. In conclusion, our study demonstrates the first attempt to identify Wnt5a and Ror2 as additional mechanisms contributing to dysregulation of the non‐canonical WNT signaling pathway in MB. Ror2 may play a role as an oncosuppressor in MB.  相似文献   
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ObjectiveTo assess the performance of diffusion tensor imaging (DTI) for the diagnosis of cervical spondylotic myelopathy (CSM) in patients with deformed spinal cord but otherwise unremarkable conventional magnetic resonance imaging (MRI) findings.ResultsThe MD, LD, and RD cut-off values were 1.079 × 10-3, 1.719 × 10-3, and 0.749 × 10-3 mm2/sec, respectively, and that of FA was 0.475. Sensitivity, specificity, positive predictive value and negative predictive value were: 100 (4/4), 44.8 (13/29), 20 (4/20), and 100 (13/13) for MD; 100 (4/4), 27.6 (8/29), 16 (4/25), and 100 (8/8) for FA; 100 (4/4), 58.6 (17/29), 25 (4/16), and 100 (17/17) for MD∩FA; 100 (4/4), 68.9 (20/29), 30.8 (4/13), and 100 (20/20) for LD∩FA; and 75 (3/4), 68.9 (20/29), 25 (3/12), and 95.2 (20/21) for RD∩FA in percentage value. Diagnostic performance comparisons revealed significant differences only in specificity between FA and MD∩FA (p = 0.003), FA and LD∩FA (p < 0.001), FA and RD∩FA (p < 0.001), MD and LD∩FA (p = 0.024) and MD and RD∩FA (p = 0.024).ConclusionFractional anisotropy combined with MD, RD, or LD is expected to be more useful than FA and MD for diagnosing CSM in patients who show deformed spinal cords without signal changes on MRI.  相似文献   
105.

Objective

The aims of this study were to compare opening and closing angles of normally functioning mechanical aortic valves measured on dual-source computed tomography (CT) with the manufacturers'' values and to compare CT-measured opening angles according to valve function.

Materials and Methods

A total of 140 patients with 10 different types of mechanical aortic valves, who underwent dual-source cardiac CT, were included. Opening and closing angles were measured on CT images. Agreement between angles in normally functioning valves and the manufacturer values was assessed using the interclass coefficient and the Bland-Altman method. CT-measured opening angles were compared between normal functioning valves and suspected dysfunctioning valves.

Results

The CT-measured opening angles of normally functioning valves and manufacturers'' values showed excellent agreement for seven valve types (intraclass coefficient [ICC], 0.977; 95% confidence interval [CI], 0.962-0.987). The mean differences in opening angles between the CT measurements and the manufacturers'' values were 1.2° in seven types of valves, 11.0° in On-X valves, and 15.5° in ATS valves. The manufacturers'' closing angles and those measured by CT showed excellent agreement for all valve types (ICC, 0.953; 95% CI, 0.920-0.972). Among valves with suspected dysfunction, those with limitation of motion (LOM) and an increased pressure gradient (PG) had smaller opening angles than those with LOM only (p < 0.05).

Conclusion

Dual-source cardiac CT accurately measures opening and closing angles in most types of mechanical aortic valves, compared with the manufacturers'' values. Opening angles on CT differ according to the type of valve dysfunction and a decreased opening angle may suggest an elevated PG.  相似文献   
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The total cost of hematopoietic stem cell transplantation (HSCT) as well as the financial impact of HSCT on the house holds of patients have been elusive. Between 2005 and 2012, we analyzed 191 HSCT in adult patients with leukemia with reduced‐intensity conditioning (RIC) regimen (n = 79) and with myeloablative conditioning (MAC) regimen (n = 112). The direct medical costs were calculated from healthcare claims obtained from the Seoul National University Hospital, and the direct non‐medical and the indirect costs were calculated from national statistics. The mean direct medical cost was $55 039, direct non‐medical cost was $6394, and indirect cost was $7503 from transplantation to one yr after transplantation in the RIC group and $72 916, $6993, and $9057 in the MAC group, respectively, based on the exchange rate of Korean won 1060 = US$1. The total costs for one yr were $68 938 and $88 967, constituting for 273% and 357% of the per capita income, respectively. The total costs, direct medical costs, and indirect costs showed statistically significant differences (p = 0.006, p = 0.007, and p = 0.017). No significant differences were found for leukemia‐free survival and overall survival. RIC‐HSCT provides lower costs within the first year of transplantation with comparable long‐term clinical outcomes.  相似文献   
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Introduction

Spinal arteriovenous fistula (AVF) is treated by embolization or surgery. However, transarterial embolization or surgery is difficult in rare cases when the fistula site is very complicated to access especially as in fistular nidus supplied by posterior and anterior spinal artery. We present the case which was treated with intraoperative direct puncture and embolization (IOPE) using glue material, since the usual transarterial or transvenous neurointerventional approach was difficult to embolize the AVF.

Methods

A 36-year-old woman presented with progressive leg weakness and pain after a 20-year history of lower back pain. She had pelvic and spinal AVF combined with arteriovenous malformation (AVM). Despite prior treatment of the pelvic lesion with radiotherapy and coil embolization, the spinal lesion persisted and caused repeated subarachnoid hemorrhages. A spinal angiogram revealed a tortuous and long feeder of the AVF which had growing venous sac, as well as AVM. Two embolization trials failed because of the long tortuosity and associated anterior spinal artery. Four months later, drastic leg weakness and pain occurred, and IOPE was performed using a glue material.

Results

The subsequent recovery of the patient was rapid. One month later, the use of a strong opioid could be discontinued, and the patient could walk with aid. A follow-up spinal angiogram revealed that the venous sac of the AVF had disappeared.

Conclusion

In spinal AVF which is not feasible to access by usual intervention approach and to dissect surgically, IOPE with glue material can be considered for the treatment.

  相似文献   
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