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The behaviour of nanoscale optical devices in a variety of burgeoning research areas, such as photonic crystals, near-field microscopy, surface plasmonics and negative index of refraction materials, is governed by strongly localized electromagnetic waves. Although such light waves are analogous to the localized electronic wavefunctions that determine the properties of solid-state quantum devices, unlike matter waves, these optical fields are vectorial in nature, and their orientation and magnitude vary on a subwavelength scale. In order to obtain a complete description of light in nanoscale devices, it is therefore crucial to be able to map the field vectors with subwavelength resolution. Thus far, local field vectors have mostly been studied by theoretical means. Here, we describe and demonstrate the first experimental mapping of vector fields of light on the nanoscale. By directly accessing the local field in its entirety, new capabilities and applications in nanophotonics may emerge. [ABSTRACT FROM AUTHOR]

Kidney transplantation is the most desired modality of renal replacement therapy for patients with end-stage renal disease (ESRD). We have attempted to expand the organ donor pool through several methods, including the use of expanded donor criteria. Although previously transplanted kidneys are rarely reused, they can be suitable for transplantation into patients in need. We report a case of successful reuse of a previously transplanted kidney from a deceased donor by means of Luminex virtual crossmatching with the first donor and actual crossmatching with the second donor. [ABSTRACT FROM AUTHOR]

Background: Invasive aspergillosis (IA) is a rare condition that generally affects immunosuppressed patients. The mortality of IA is known to be >90% in liver transplantation (LT) recipients; the lung is the most commonly affected organ, followed by the brain. There have been reports in the literature of cerebral aspergillosis (CA) in LT recipients. In all previous reports, CA developed after LT. We present the first case (to the best of our knowledge) of preexisting CA diagnosed and successfully treated after LT., Case Report: A 59-year-old male patient underwent emergency deceased-donor LT for alcoholic liver cirrhosis. Preoperative imaging showed multiple lesions in both cerebral hemispheres, indicative of brain abscess or metastases. Before definitive diagnosis of the brain lesion, the deceased-donor LT was performed. On postoperative day 15, the patient developed a fever of 38.0°C and drowsy mental status. Magnetic resonance imaging showed increased number and size of brain abscesses. Stereotactic brain abscess aspiration was performed, and pathologic findings revealed aspergillosis. Voriconazole was started immediately. The patient improved steadily and was discharged 1 month after initiation of voriconazole treatment., Conclusions: This case is the first report of preexisting CA treated successfully after LT. Voriconazole is a potent therapeutic agent of CA. When LT is performed with an undiagnosed brain lesion, aggressive diagnostic measures are necessary postoperatively. If CA is diagnosed, successful treatment may be possible with voriconazole., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Aim: To compare the abilities of conventional magnetic resonance imaging (MRI) and apparent diffusion coefficient (ADC) in differentiating between benign and malignant soft-tissue tumours (STT)., Material and Methods: A total of 123 patients with STT who underwent 3 T MRI, including diffusion-weighted imaging (DWI), were retrospectively analysed using variate conventional MRI parameters, ADC mean and ADC min ., Results: For the all-STT group, the correlation between the malignant STT conventional MRI parameters, except deep compartment involvement, compared to those of benign STT were statistically significant with univariate analysis. Maximum diameter of the tumour (p=0.001; odds ratio [OR], 8.97) and ADC mean (p=0.020; OR, 4.30) were independent factors with multivariate analysis. For the non-myxoid non-haemosiderin STT group, signal heterogeneity on axial T1-weighted imaging (T1WI; p=0.017), ADC mean , and ADC min (p=0.001, p=0.001), showed significant differences with univariate analysis between malignancy and benignity. Signal heterogeneity in axial T1WI (p=0.025; OR, 12.64) and ADC mean (p=0.004; OR, 33.15) were independent factors with multivariate analysis., Conclusion: ADC values as well as conventional MRI parameters were useful in differentiating between benign and malignant STT. The ADC mean was the most powerful diagnostic parameter in non-myxoid non-haemosiderin STT., (Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Aim: To evaluate and compare the diagnostic performance of quantitative parameters derived from diffusion-weighted imaging (DWI) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in differentiating benign and malignant bone tumours., Materials and Methods: Fifty-five patients (age range, 21-82 years; mean age, 55 years) underwent pretreatment MRI. Apparent diffusion coefficient (ADC) values were calculated by DWI. The DCE-MRI data were analysed for the volume transfer constant (K trans ), extravascular extracellular volume fraction (V e ), and volume rate constant (K ep ), and K trans /ADC ratio. Each parameter's performance was evaluated using the area under the receiver operating characteristic (ROC) curv (AUC), and their AUCs were compared. ROC curves were analysed and each parameter's optimal cut-off value was determined, from which each parameter was evaluated for sensitivity, specificity, accuracy, and positive and negative predictive values. The odds ratio (OR) with 95% confidence interval for detecting malignant bone lesions after adjusting the age factor of each parameter was estimated., Results: All parameter values (except V e ) were significantly different between benign and malignant bone tumours (p<0.05). The K trans had a significantly greater AUC than V e (p=0.03). The K trans /ADC and K ep had the best sensitivity (0.917) and specificity (0.632), respectively. The K ep and K trans /ADC had the best positive (0.811) and negative (0.769) predictive values, respectively. The OR was highest for K trans /ADC (17.38; p=0.0013)., Conclusion: The K trans , K ep , ADC, and K trans /ADC could help to detect malignant lesions from bone tumours and K trans /ADC appears to be the superior variable among them., (Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Background: Large-for-size (LFS) is a serious problem that can develop during liver transplantation (LT) and is related to morbidities such as insufficient blood supply causing graft dysfunction or impractical closure of the abdominal wall leading to graft compression. LFS is usually discussed in pediatric LT and is often managed by reducing the size of the graft before implantation. In contrast, only a few cases about managing unexpected LFS during adult LT have been reported, and no case after the vascular anastomosis has been completed has been reported., Case Report: A 36-year-old, 43-kg woman underwent an emergency LT using a deceased donor, although the estimated graft/recipient weight ratio was 3.98%. After completing the vascular anastomosis, a severe hepatic venous outflow obstruction from the graft developed due to compression of the inferior vena cava from the hypertrophied right posterior lobe of the graft. We performed a right hemihepatectomy sequentially after LT, and hepatic blood flow recovered sufficiently based on a Doppler sonogram. The postoperative clinical course was uneventful without vascular or ductal complications, and the primary abdominal wall closure was successfully achieved without wound complications., Conclusions: Performing a right hemihepatectomy sequentially after completing the vascular anastomosis during LT could be a very simple and effective solution for unexpected LFS during LT., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Aim: To evaluate whether the apparent diffusion coefficient (ADC) of metastatic bone tumours on diffusion-weighted magnetic resonance imaging (MRI) images differs according to the type of primary cancer, the affected bone, and clinical factors., Materials and Methods: For this retrospective study, two radiologists reviewed MRI images, including ADC maps, of 67 patients (M:F=38:29; median age, 48 years) who were diagnosed with bone metastasis by means of histological or clinical confirmation. The primary tumours included 29 lung adenocarcinomas, 15 invasive ductal adenocarcinomas of the breast, 13 hepatocellular carcinomas, six prostatic carcinomas, and four renal cell carcinomas. ADC values of the metastatic tumour were compared according to the type of primary malignancy, the affected bone, and the age and sex of the patient using Kruskal-Wallis and Mann-Whitney U-tests with Bonferroni correction. In addition, pre-contrast CT images were available in 38 of 67 patients; a subanalysis of the CT radiodensity and ADC values were performed with Spearman correlation., Results: The mean, standard deviation, and minimum and maximum values of the ADC of metastatic bone tumours did not differ significantly according to type of primary malignancy, the affected bone, or clinical variables (p>0.1). The ADC value was not significantly correlated with CT radiodensity (p=0.24). Intra- and interobserver agreements for the mean ADC values were excellent (intra-observer: p=0.98; interobserver: p=0.98)., Conclusions: Assessment of the ADC value of metastatic bone tumours is not reliable for differentiation of the type of primary cancer., (Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Aim: To evaluate differences in T2 relaxation time of ankle cartilage using magnetic resonance imaging (MRI) according to the status of the anterior talofibular ligament (ATFL)., Materials and Methods: The talar trochlear cartilage (TTC) was evaluated in 52 patients with ankle pain that were categorized according to the status of ATFL; normal (NL; n = 23, mean age 40 years); partial tear (PT; n = 21, mean age 39 years); or complete tear (CT; n = 8, mean age 33 years). The TTC was divided into six compartments (medial anterior, medial centre, medial posterior, lateral anterior, lateral centre, and lateral posterior). The mean T2 value of each compartment was obtained using the multi-echo sequence. Data were analysed with parametric and non-parametric statistical tests., Results: The mean T2 values of the TTC showed significant differences between the three groups; NL, PT, and CT (p < 0.001). The T2 value between the three ligamentous groups were significantly different in the medial anterior, lateral anterior, and lateral centre compartments (p = 0.003, 0.002, 0.002, respectively). T2 values of the PT and CT groups were significantly higher than those of the NL group in the medial anterior compartment (p = 0.015, 0.002) and lateral anterior compartment (p = 0.026, <0.001). The T2 value of the CT group was significantly higher than that of NL and PT groups in the lateral centre compartment (p < 0.001, 0.031)., Conclusion: The T2 value of the TTC in patients with ATFL injury increased at the medial anterior, lateral anterior, and lateral centre compartments., (Copyright © 2013 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Aim: To compare three-dimensional (3D) isotropic T2-weighted magnetic resonance imaging (MRI) sequences and reformation with two-dimensional (2D) T2-weighted sequences regarding image quality of the cervical spine at 3T., Materials and Methods: A phantom study was performed using a water-filled cylinder. The signal-to-noise and image homogeneity were evaluated. Fourteen (n=14) volunteers were examined at 3T using 3D isotropic T2-weighted sagittal and conventional 2D T2-weighted sagittal, axial, and oblique sagittal MRI. Multiplanar reformation (MPR) of the 3D T2-weighted sagittal dataset was performed simultaneously with image evaluation. In addition to artefact assessment, the visibility of anatomical structures in the 3D and 2D sequences was qualitatively assessed by two radiologists independently. Cohen's kappa and Wilcoxon signed rank test were used for the statistical analysis., Result: The 3D isotropic T2-weighted sequence resulted in the highest signal-to-noise ratio (SNR) and lowest non-uniformity (NU) among the sequences in the phantom study. Quantitative evaluation revealed lower NU values of the cerebrospinal fluid (CSF) and muscles in 2D T2-weighted sagittal sequences compared to the 3D volume isotropic turbo spin-echo acquisition (VISTA) sequence. The other NU values revealed no statistically significant difference between the 2D turbo spin-echo (TSE) and 3D VISTA sequences (0.059

Patient genetic make-up may contribute to a higher risk for acute rejection episodes (AREs). Because interleukin-2 (IL2) and IL2 receptor β (IL2RB) play key roles in immune modulation, we investigated the effect of single-nucleotide polymorphisms (SNPs) in the IL2 gene (rs2069762; T>G, promoter; and rs2069763; G>T, exon 1, Leu38Leu) and IL2RB gene (rs228942: C>A, exon 1, Asp391Glu; and rs228953: C>T, exon 8, Gly250Gly) on renal ARE risk in 61 ARE patients and 276 control renal allograft recipients in Korea. The genotype frequencies of the IL2 and IL2RB SNPs showed Hardy-Weinberg equilibrium in both ARE and control groups. No significant difference in the genotype frequencies of the 2 IL2 SNPs was detected between non-ARE and ARE subjects (P > .05). The occurrence of AREs was significantly associated with genetic variants of the IL2RB gene (rs228942: odds ratio [OR] 2.11, 95% confidence interval [CI] 1.19-3.74; P = .0096, dominant model; rs228953: OR 1.58, 95% CI 1.04-2.38; P = .029, codominant model). In the haplotype-based analysis, the AC haplotype of IL2RB (χ(2) = 4.738; P = .0295) showed associations with ARE. Our results demonstrate that genetic variants of IL2RB may be associated with the development of AREs and may help predict ARE risk in kidney transplantation patients., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Aim: To evaluate the diagnostic role of additional oblique coronal and oblique sagittal magnetic resonance imaging (MRI) for an anterior cruciate ligament (ACL) tear., Materials and Methods: A total of 101 patients who had undergone preoperative knee MRI examinations with orthogonal and two sets of oblique images were enrolled in the study. Two radiologists evaluated the MRI images by the use of four methods: orthogonal images only (method A); orthogonal and additional oblique coronal images (method B); orthogonal and oblique sagittal images (method C); and orthogonal images with oblique coronal and sagittal images (method D). The status of the ACL (normal or tear) was determined by consensus. The sensitivity, specificity, and accuracy for an ACL tear with the use of each method were calculated in comparison with arthroscopy as the reference standard, and values were statistically analysed using the McNemar test. The diagnostic accuracies were compared using receiver operating characteristic (ROC) analysis., Results: Arthroscopy identified 10 partial ACL tears and 30 complete ACL tears. The specificities and accuracies for methods B, C, and D were significantly higher than the specificities and accuracies for method A (p<0.05). There was no significant difference in the sensitivity, specificity, and accuracy for methods B, C, and D. Diagnostic ability was not significantly different for each method, as determined by ROC analysis (p>0.05)., Conclusions: Additional oblique imaging for an ACL tear improved the specificity. Either of the oblique imaging methods is sufficient, and no further improvement in the diagnostic efficacy was achieved by simultaneous use.

Nocardia is a rare gram-positive bacteria causing opportunistic infection, and belongs to the aerobic Actinomycetes group. As the mortality in the immunocompromised patients with nocardiosis is high, early diagnosis and treatment is very important. However, clinical manifestations of infection caused by Nocardia are very variable and early diagnosis is limited by the difficulty in obtaining specimens and its isolation. Rapid diagnosis of Nocardia infection may allow for earlier effective therapy, thus improving patient outcome. We report a case of Nocardia farcinica diagnosed by DNA sequencing through blood culture in a renal transplant recipient with severe pneumonia and multiple brain abscesses.

The stimulatory effect of iron and ascorbate on the damaging action of cyclosporine in kidney mitochondria, microsomes and epithelial cells was examined. Cyclosporine induced malondialdehyde formation and hydrogen peroxide production in mitochondria and attenuated the activity of MnSOD and glutathione peroxidase. The damaging effect of cyclosporine (50 microM) plus Fe2+(20 microM) on mitochondrial and microsomal lipids and proteins as well as mitochondrial thiols was greater than the summation of the oxidizing action of cyclosporine alone and Fe2+ alone. As for tissue components, iron enhanced cyclosporine-induced viability loss in kidney epithelial cells. Fe2+, EDTA and H2O2- induced 2-alpha deoxyribose degradation was attenuated by 10 mM DMSO and 200 microM DTPA but not affected by 200 microM cyclosporine. The addition of Fe2+ caused a change in the absorbance spectrum of cyclosporine in the wavelength range 230-350 nm. The simultaneous addition of cyclosporine (50 microM) and ascorbate (100 microM) showed the enhanced peroxidative effect on mitochondrial and microsomal lipids, which was inhibited by DTPA and EDTA (1 mM). Similar to iron, ascorbate enhanced cyclosporine-induced cell viability loss. The results show that iron and ascorbate promote the damaging action of cyclosporine in kidney cortex mitochondria and microsomes and in kidney epithelial cells, which may contribute to the enhancement of cyclosporine-induced nephrotoxicity., (Copyright 2001 Academic Press.)