349 research outputs found
Luminance enhancement of electroluminescent devices using highly dielectric UV-curable polymer and oxide nanoparticle composite
A flexible hybrid structure electroluminescent (HSEL) device was fabricated from ZnS:Cu phosphor microparticles dispersed in a UVcurable polymer matrix. We observed a maximum luminance of 111 cd/m2 at 10 kHz and 170 V from a device wherein the mixing ratio between the phosphor particles and highly dielectric polymer binder was 70:30 wt%. Furthermore, by uniformly dispersing highly dielectric BaTiO3 nanoparticles within the polymer matrix, we were able to obtain a luminance of up to 211 cd/m2 in the HSEL device. Compared to the conventional thermal curing process, this UV process greatly simplifies the fabrication steps by combining phosphors and dielectric materials at room temperature. This process also demonstrates a promising pathway toward creating flexible and printed EL devices in the future. © 2014 Optical Society of America.1
Assessment of Lymph Node Metastases by Contrast-Enhanced MR Imaging in a Head and Neck Cancer Model
OBJECTIVE: We wanted to investigate the accuracy of contrast-enhanced MR imaging for the detection of lymph node metastases in a head and neck cancer rabbit model. MATERIALS AND METHODS: The metastatic lymph node model we used was created by inoculating VX2 tumors into the auricles of six New Zealand White rabbits. T1-weighted MR images were obtained before and after injecting gadopentetate dimeglumine at three weeks after tumor cell inoculation. The sizes, signal intensity ratios (i.e., the postcontrast signal intensities of the affected nodes relative to the adjacent muscle) and the enhancement patterns of 36 regional lymph nodes (parotid and caudal mandibular nodes) were evaluated on MR images and then compared with the histopathologic findings. RESULTS: No statistical difference was found between the sizes of 12 metastatic (10.5+/-3.2 mm) and 24 hyperplastic (8.0+/-3.6 mm) lymph nodes (p > 0.05). On the contrast-enhanced T1-weighted MR images, nine metastatic and four hyperplastic lymph nodes had peripheral high and central low signal intensity, whereas three metastatic and 20 hyperplastic lymph nodes had homogeneous high signal intensity. Using a signal intensity ratio less than one as a diagnostic criterion for a metastatic lymph node, the sensitivity, specificity and positive and negative predictive values of the enhanced MR images were 75% (9/12), 83% (20/24), 69% (9/13) and 87% (20/23), respectively, with areas under receiver-operating-characteristic curve values of 0.81. CONCLUSION: This experimental study confirms that metastatic and hyperplastic lymph nodes can be differentiated using MR images on the basis of the contrast uptake patterns, but that they cannot be differentiated using any particular size criteria
Abdominal Aortic Aneurysm Repair in Patient with a Renal Allograft: A Case Report
Renal transplant recipients requiring aortic reconstruction due to abdominal aortic aneurysm (AAA) pose a unique clinical problem. The concern during surgery is causing ischemic injury to the renal allograft. A variety of strategies for protection of the renal allograft during AAA intervention have been described including a temporary shunt, cold renal perfusion, extracorporeal bypass, general hypothermia, and endovascular stent-grafting. In addition, some investigators have reported no remarkable complications of the renal allograft without any specific measures. We treated a case of AAA in a patient with a renal allograft using a temporary aortofemoral shunt with good result. Since this technique is safe and effective, it should be considered in similar patients with AAA and previously placed renal allografts
Molecular Subgroup Analysis of Clinical Outcomes in a Phase 3 Study of Gemcitabine and Oxaliplatin with or without Erlotinib in Advanced Biliary Tract Cancer
AbstractBACKGROUND: We previously reported that the addition of erlotinib to gemcitabine and oxaliplatin (GEMOX) resulted in greater antitumor activity and might be a treatment option for patients with biliary tract cancers (BTCs). Molecular subgroup analysis of treatment outcomes in patients who had specimens available for analysis was undertaken. METHODS: Epidermal growth factor receptor (EGFR), KRAS, and PIK3CA mutations were evaluated using peptide nucleic acid–locked nucleic acid polymerase chain reaction clamp reactions. Survival and response rates (RRs) were analyzed according to the mutational status. Sixty-four patients (48.1%) were available for mutational analysis in the chemotherapy alone group and 61 (45.1%) in the chemotherapy plus erlotinib group. RESULTS: 1.6% (2/116) harbored an EGFR mutation (2 patients; exon 20), 9.6% (12/121) harbored a KRAS mutation (12 patients; exon 2), and 9.6% (12/118) harbored a PIK3CA mutation (10 patients, exon 9 and 2 patients, exon 20). The addition of erlotinib to GEMOX in patients with KRAS wild-type disease (n = 109) resulted in significant improvements in overall response compared with GEMOX alone (30.2% vs 12.5%, P = .024). In 95 patients with both wild-type KRAS and PIK3CA, there was evidence of a benefit associated with the addition of erlotinib to GEMOX with respect to RR as compared with GEMOX alone (P = .04). CONCLUSION: This study demonstrates that KRAS mutational status might be considered a predictive biomarker for the response to erlotinib in BTCs. Additionally, the mutation status of PIK3CA may be a determinant for adding erlotinib to chemotherapy in KRAS wild-type BTCs
The Relationship between B7-H4 Expression and Clinicopathological Characteristics in Clinical Stage T1 Conventional Renal Cell Carcinoma
Clinical Outcomes of Single-level Posterior Percutaneous Endoscopic Cervical Foraminotomy for Patients with Less Cervical Lordosis
Objective Posterior percutaneous endoscopic cervical foraminotomy (P-PECF) is a minimally invasive surgical technique for treatment of cervical radiculopathies. Application of P-PECF to patients with preexisting loss of cervical curvature (<10°) is still controversial because violation to facet joint may lead to kyphotic change. Clinical outcomes of P-PECF was analyzed and compared according to preoperative cervical curvature. Methods In this retrospective nested case-control study, 71 patients who underwent P-PECF due to foraminal soft disc herniation or bony stenosis were reviewed. P-PECF was performed by a single senior surgeon, and surgical methods were as previously described. Visual analogue pain scale on arm (Arm-VAS) was assessed preoperatively and postoperatively (1, 3, 6, 12 month and yearly thereafter). All patients were clinically followed for 24.5±20.0 months. The minimal clinically important difference of the Arm-VAS was set at 2.5. Patients with preoperative cervical curvature ≥10° were included in group I (n=32) and cervical curvature <10° or kyphosis were included in the group II (n=39). Results At the last follow up, 68/71 (96%) patients showed significant reduction of arm pain (Pre-operation, 7.4±2.0; post-operation, 1.5±2.0) after 1.74±0.29 months (95% CI; 1.18-2.31). The preoperative cervical curvature did not influence the outcome (p=0.4, T-test) and time to reach the clinical endpoint (p=0.34, Cox-logistic regression analysis). Conclusion P-PECF effectively reduced radicular pain due to foraminal soft disc herniation or stenosis. Preexisting loss of lordosis is not a risk factor for outcomes of P-PECF
Different contribution of extent of myocardial injury to left ventricular systolic and diastolic function in early reperfused acute myocardial infarction
BACKGROUND: We sought to investigate the influence of the extent of myocardial injury on left ventricular (LV) systolic and diastolic function in patients after reperfused acute myocardial infarction (AMI).
METHODS: Thirty-eight reperfused AMI patients underwent cardiac magnetic resonance (CMR) imaging after percutaneous coronary revascularization. The extent of myocardial edema and scarring were assessed by T2 weighted imaging and late gadolinium enhancement (LGE) imaging, respectively. Within a day of CMR, echocardiography was done. Using 2D speckle tracking analysis, LV longitudinal, circumferential strain, and twist were measured.
RESULTS: Extent of LGE were significantly correlated with LV systolic functional indices such as ejection fraction (r��=��-0.57, p��<��0.001), regional wall motion score index (r��=��0.52, p��=��0.001), and global longitudinal strain (r��=��0.56, p��<��0.001). The diastolic functional indices significantly correlated with age (r��=��-0.64, p��<��0.001), LV twist (r��=��-0.39, p��=��0.02), average non-infarcted myocardial circumferential strain (r��=��-0.52, p��=��0.001), and LV end-diastolic wall stress index (r��=��-0.47, p��=��0.003 with e') but not or weakly with extent of LGE. In multivariate analysis, age and non-infarcted myocardial circumferential strain independently correlated with diastolic functional indices rather than extent of injury.
CONCLUSIONS: In patients with timely reperfused AMI, not only extent of myocardial injury but also age and non-infarcted myocardial function were more significantly related to LV chamber diastolic function.ope
Generalised optical printing of photocurable metal chalcogenides
Optical three-dimensional (3D) printing techniques have attracted tremendous attention owing to their applicability to mask-less additive manufacturing, which enables the cost-effective and straightforward creation of patterned architectures. However, despite their potential use as alternatives to traditional lithography, the printable materials obtained from these methods are strictly limited to photocurable resins, thereby restricting the functionality of the printed objects and their application areas. Herein, we report a generalised direct optical printing technique to obtain functional metal chalcogenides via digital light processing. We developed universally applicable photocurable chalcogenidometallate inks that could be directly used to create 2D patterns or micrometre-thick 2.5D architectures of various sizes and shapes. Our process is applicable to a diverse range of functional metal chalcogenides for compound semiconductors and 2D transition-metal dichalcogenides. We then demonstrated the feasibility of our technique by fabricating and evaluating a micro-scale thermoelectric generator bearing tens of patterned semiconductors. Our approach shows potential for simple and cost-effective architecturing of functional inorganic materials
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