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Silicon nitrides, deposited by capacitively coupled plasma (CCP)-type plasma enhanced atomic layer deposition (PEALD), are generally applied to today’s nanoscale semiconductor devices, and are currently being investigated in terms of their potential applications in the context of flexible displays, etc. During the PEALD process, 13.56 MHz rf power is generally employed for the generation of reactive gas plasma. In this study, the effects of a higher plasma generation frequency of 162 MHz on both plasma and silicon nitride film characteristics are investigated for the purpose of silicon nitride PEALD, using bis(diethylamino)silane (BDEAS) as the silicon precursor, and N2 plasma as the reactant gas. The PEALD silicon nitride film deposited using the 162 MHz CCP exhibited improved film characteristics, such as reduced surface roughness, a lower carbon percentage, a higher N/Si ratio, a lower wet etch rate in a diluted HF solution, lower leakage current, and higher electric breakdown field, and more uniform step coverage of the silicon nitride film deposited in a high aspect ratio trench, as compared to silicon nitride PEALD using 13.56 MHz CCP. These improved PEALD silicon nitride film characteristics are believed to be related to the higher ion density, higher reactive gas dissociation, and lower ion bombardment energy to the substrate observed in N2 plasma with a 162 MHz CCP.

To cite this article: Cheong HS, Park S-M, Kim M-O, Park J-S, Lee JY, Byun JY, Park BL, Shin HD, Park C-S. Genome-wide methylation profile of nasal polyps: relation to aspirin hypersensitivity in asthmatics. Allergy 2011; 66: 637–644. Abstract Background: In addition to the dysregulation of arachidonic acid metabolism in aspirin-intolerant asthma (AIA), aspirin acetylsalicylic acid (ASA) exerts effects on inflammation and immunity; however, many of these effects are unknown. Objective: The aim of the study was to evaluate the methylation status of whole genome in blood and polyp tissues with and without aspirin hypersensitivity. Methods: Genome-wide DNA methylation levels in nasal polyps and peripheral blood cells were examined by microarray analysis using five subjects with AIA and four subjects with aspirin-tolerant asthma (ATA). Results: In the nasal polyps of the patients with AIA, hypermethylation was detected at 332 loci in 296 genes, while hypomethylation was detected at 158 loci in 141 genes. Gene ontologic and pathway enrichment analyses revealed that genes involved in lymphocyte proliferation, cell proliferation, leukocyte activation, cytokine biosynthesis, cytokine secretion, immune responses, inflammation, and immunoglobulin binding were hypomethylated, while genes involved in ectoderm development, hemostasis, wound healing, calcium ion binding, and oxidoreductase activity were hypermethylated. In the arachidonate pathway, PGDS, ALOX5AP, and LTB4R were hypomethylated, whereas PTGES was hypermethylated. Conclusion: The nasal polyps of patients with AIA have characteristic methylation patterns affecting 337 genes. The genes and pathways identified in this study may be associated with the presence of aspirin hypersensitivity in asthmatics and are therefore attractive targets for future research.

Lipomatous haemangiopericytoma (a fat-forming solitary fibrous tumour) is a rare soft-tissue tumour histologically characterized by haemangiopericytomatous vasculature and the presence of mature adipocytes. We report the CT and MRI findings of a case of lipomatous haemangiopericytoma involving the perineum. CT showed a well-circumscribed soft-tissue density mass containing a small area of fat density and a punctuate calcification. On MR images, the mass was mostly isointense to the muscle on T(1) weighted images, with heterogeneous signal intensity on T(2) weighted images, and showed strong contrast enhancement except for the fatty and dense collagenous components. This is the first case report of imaging findings of a lipomatous haemangiopericytoma in the radiological literature. Although rare, lipomatous haemangiopericytoma should be considered as a differential diagnosis of fat-containing, hypervascular soft-tissue tumours with variable signal intensity on T(2) weighted images.

To evaluate the helical CT findings of ruptured hepatocellular carcinoma (HCC), 12 patients with ruptured HCC were reviewed with regard to the tumour's location, size and contour protrusion, the appearance of the mass, the enhancement pattern, multiplicity and secondary changes. All ruptured tumours were located at the periphery of the liver and had a protruding contour. The maximum diameter of tumours ranged from 2 cm to 16 cm. Discontinuity of the hepatic surface was seen in 11 cases. In eight cases, CT images during the arterial phase showed a non-enhancing low attenuating lesion with focal discontinuity and peripheral rim enhancement. Seven cases showed separation of tumour content from the peripheral enhancing rim and intraperitoneal rupture of tumour content into the perihepatic space. Because of the similar appearance to an enucleated orbital globe with remaining sclera, this was termed the "enucleation sign". As well as ruptured masses, 10 cases with non-ruptured masses also showed a non-enhancing low attenuating pattern. Seven cases showed a haematoma with high attenuation around the ruptured mass. The peripheral location, protruding contour, discontinuity of the hepatic surface and surrounding haematoma are helpful signs in the diagnosis of ruptured HCC. The "enucleation sign" may be a characteristic finding in ruptured HCC.

The purpose was to evaluate angiographic and CT manifestations of vascular Behçet's disease. The medical records of 64 patients with Behçet's disease, treated in our hospital during the last 4 years, were reviewed. 37 patients underwent angiography or CT in the symptomatic regions because of symptoms or clinical signs of vascular involvement by Behçet's disease. 33 (male:female ratio 28:5; mean age 35 years) of the 37 patients demonstrated vascular involvement, which was surgically proven (18 patients) or diagnosed on angiography (15 patients). Angiograms and CT images of these 33 patients were retrospectively analysed for lesion type, location, extent and other characteristic findings of vascular involvement. 12 patients had only venous lesions, 11 had only arterial lesions and 10 had both arterial and venous lesions. The major angiographic findings of vascular Behçet's disease were acute or chronic thrombosis in deep veins of the lower extremities (19 patients), in the inferior vena cava (4 patients) and in the superior vena cava (2 patients), pseudoaneurysms of large or medium sized arteries (11 patients), and occlusions/ stenoses of distal run-off arteries (13 patients). Common CT findings were obliterated deep veins (8 patients) and non-calcified thickened aneurysmal walls (9 patients), with or without contrast enhancement. The combination of these angiographic and CT findings with clinical manifestations are helpful in distinguishing vascular Behçet's disease from other vasculitides.

Haemangioma is an extremely rare tumour of the ovary. We describe the CT and MRI findings of a heavily calcified ovarian haemangioma in a 69-year-old woman presenting with adnexal torsion. CT showed a well-circumscribed mass with extensive punctate calcifications, located posterior to the uterus. MR images showed dark signal intensities of the mass on both T(1) and T(2) weighted images, with poor enhancement of the mass on contrast-enhanced T(1) weighted images. MR images also demonstrated a beak-like protrusion from the adnexal mass, representing the adnexal torsion. This is the first case report of a heavily calcified ovarian haemangioma in the English literature. Although rare, ovarian haemangioma should be included in the differential diagnosis of a heavily calcified adnexal mass.

Purpose: to investigate the utility of the resistive indices (RIs) of the epididymal and intratesticular arteries, and to establish diagnostic criteria for scrotal inflammatory disease on the basis of quantitative color Doppler sonography Material and Methods: We prospectively examined 29 consecutive patients with scrotal pain, and 15 normal control subjects. the RIs of the intratesticular and epididymal arteries were obtained from color Doppler sonographs Results: the RIs of the testicular artery in epididymoorchitis were significantly lower than those in normal control subjects and in epididymitis (p0.5). with a cut-off value of RI=0.5, sensitivity, specificity, accuracy, and positive and negative predictive values were 91%, 94%, 94%, 83%, and 77% respectively. the mean RI of the epididymal arteries in epididymitis and epididymoorchitis was 0.49±0.11. A high level of diagnostic accuracy in scrotal inflammatory disease was achieved when the RIs of the intratesticular and epididymal arteries were less than 0.5 and 0.7 respectively Conclusion: the RI of the intrascrotal artery would give a more objective evaluation than subjective assessment and could provide diagnostic criteria for scrotal inflammatory disease

The partial oxidation of dimethyl ether (DME) was investigated using the structured catalyst Rh/Al2O3/Al. The porous Al2O3 layer was synthesized on the aluminum plate through anodic oxidation in an oxalic-acid solution. It was observed that about 20 nm nanopores were well developed in the Al2O3 layer. The thickness of Al2O3 layer can be adjusted by controlling the anodizing time and current density. After pore-widening and hot-water treatment, the Al2O3/Al plate was calcined at 500 degrees C for 3 h. The obtained delta-Al2O3 had a specific surface area of 160 m2/g, making it fit to be used as a catalyst support. A microchannel reactor was designed and fabricated to evaluate the catalytic activity of Rh/Al2O3/Al in the partial oxidation of DME. The structured catalyst showed an 86% maximum hydrogen yield at 450 degrees C. On the other hand, the maximum syngas yield by a pack-bed-type catalyst could be attained by using a more than fivefold Rh amount compared to that used in the structured Rh/Al2O3/Al catalyst.

We reviewed CT of four patients with surgically proved bowel infarction secondary to superior mesenteric vein (SMV) thrombosis. Pathologic correlation was available in all patients. Three patients had thrombus in both portal vein and proximal SMV and the remaining patient had thrombus that was seen only in the peripheral branches of the SMV. Contrast-enhanced CT showed a segmental distribution of marked concentric bowel wall thickening in all four patients. Two patients also showed zones of different attenuation in the bowel wall, which were caused by varying degrees of edema and hemorrhage in the submucosa. Dense peripheral enhancement of the bowel wall was present in one patient. Other CT findings included ascites and mesenteric changes such as edema and vascular engorgement. The combination of thrombus in the SMV with bowel wall thickening strongly suggests bowel infarction and, therefore, warrants initiation of appropriate therapy.

In addition to the dysregulation of arachidonic acid metabolism in aspirin-intolerant asthma (AIA), aspirin acetylsalicylic acid (ASA) exerts effects on inflammation and immunity; however, many of these effects are unknown.The aim of the study was to evaluate the methylation status of whole genome in blood and polyp tissues with and without aspirin hypersensitivity.Genome-wide DNA methylation levels in nasal polyps and peripheral blood cells were examined by microarray analysis using five subjects with AIA and four subjects with aspirin-tolerant asthma (ATA).In the nasal polyps of the patients with AIA, hypermethylation was detected at 332 loci in 296 genes, while hypomethylation was detected at 158 loci in 141 genes. Gene ontologic and pathway enrichment analyses revealed that genes involved in lymphocyte proliferation, cell proliferation, leukocyte activation, cytokine biosynthesis, cytokine secretion, immune responses, inflammation, and immunoglobulin binding were hypomethylated, while genes involved in ectoderm development, hemostasis, wound healing, calcium ion binding, and oxidoreductase activity were hypermethylated. In the arachidonate pathway, PGDS, ALOX5AP, and LTB4R were hypomethylated, whereas PTGES was hypermethylated.The nasal polyps of patients with AIA have characteristic methylation patterns affecting 337 genes. The genes and pathways identified in this study may be associated with the presence of aspirin hypersensitivity in asthmatics and are therefore attractive targets for future research.

We report the imaging findings in a case of Kaposi's sarcoma involving a transplanted kidney, ureter and urinary bladder. Ultrasound and CT demonstrated multiple nodular masses in the pelvis of the transplanted kidney, ureter and bladder. The masses enhanced well on CT following i.v. contrast medium.

Haemangioma is an extremely rare tumour of the ovary. We describe the CT and MRI findings of a heavily calcified ovarian haemangioma in a 69-year-old woman presenting with adnexal torsion. CT showed a well-circumscribed mass with extensive punctate calcifications, located posterior to the uterus. MR images showed dark signal intensities of the mass on both T(1) and T(2) weighted images, with poor enhancement of the mass on contrast-enhanced T(1) weighted images. MR images also demonstrated a beak-like protrusion from the adnexal mass, representing the adnexal torsion. This is the first case report of a heavily calcified ovarian haemangioma in the English literature. Although rare, ovarian haemangioma should be included in the differential diagnosis of a heavily calcified adnexal mass.

The authors report a case of severe hypoglycemic encephalopathy in an elderly patient. The magnetic resonance images showed bilateral cortical signal changes and basal ganglia lesions, which spared the thalami. The lesions were bright on fluid-attenuated inversion recovery and diffusion-weighted images and dark on the apparent diffusion coefficient map, being more conspicuous on the diffusion-weighted images than on the fluid-attenuated inversion recovery images. A literature review of the imaging features and pathophysiological mechanism in comparison with those of hypoxic ischemic injury is discussed.

To identify neural tumor cell lines that could be used as models to study growth-related natriuretic peptide actions, we determined the effects of these peptides on the proliferation of human and rodent neuroblastoma cell lines. Subnanomolar concentrations of atrial natriuretic peptide (ANP) and type C natriuretic peptide (CNP) stimulated proliferation in all four cell lines. These actions were associated with cGMP elevation and were blocked by a protein kinase G inhibitor. These data imply the involvement of guanylyl cyclase (GC)-coupled natriuretic receptors. However, higher concentrations of ANP and CNP, and low concentrations of des-[Gln(18),Ser(19),Gly(20),Leu(21),Gly(22)]-ANP(4-23)-NH(2) (desANP(4-23)) (analog for NPR-C receptor) exerted antiproliferative actions in three of the cell lines. These effects were insensitive to a protein kinase G inhibitor and to HS-142-1, suggesting that growth-inhibitory actions involved a non-GC receptor. They did not appear to involve cAMP, protein kinase A, protein kinase C, or calcium mobilization but were abolished when constitutive mitogen-activated protein kinase activity was inhibited. Radioligand binding experiments revealed the presence of a uniform class of binding sites in NG108 cells and multiple binding sites in Neuro2a cells. Northern and reverse transcriptase-polymerase chain reaction analyses revealed differential gene expression for NPR-A/B/C in NG108 and Neuro2a cells. The results indicate that natriuretic peptides stimulate neuroblastoma cell proliferation through type NPR-A/B (GC) receptors. Higher concentrations of ANP and CNP exerted a mitogen-activated protein kinase-dependent antiproliferative action mediated by a non-GC receptor that interacts with desANP(4-23) with relatively high affinity.

Benign solitary fibrous tumour, a rare mesenchymal tumour of adults, usually arises from the pleura. Only a few cases have been reported in the retroperitoneum and, to our knowledge, there has been no report of its imaging features. We describe the MRI features of benign solitary fibrous tumour arising from the pre-sacral space.

We report a case of eosinophilic cholangitis, with US, CT, and cholangiographic findings. The lesion showed marked wall thickening of cystic and common bile ducts on US and CT together with mild diffuse narrowing of the common duct on cholangiography.

In most institutions, a combination of unenhanced and contrast-enhanced CT is used to screen patients for suspected hypervascular hepatic neoplasms. Elimination of the unenhanced examination could save time and expense and reduce the patient's exposure to radiation. We compared unenhanced and incremental bolus dynamic contrast-enhanced CT for detection of hypervascular hepatic neoplasms and evaluated the need for preliminary unenhanced hepatic CT.We prospectively examined 101 consecutive patients with hypervascular primary hepatic malignant tumors or suspected hypervascular metastases. Primary hepatic neoplasms included hepatocellular carcinoma (seven), sarcoma (two), and hemangioendothelioma (one); extrahepatic primary tumors included breast (37) and renal cell (24) carcinoma, melanoma (15), carcinoid (nine), and endocrine and other tumors (six). All patients had both unenhanced and bolus dynamic contrast-enhanced CT with 5-mm collimated sections at 8-mm intervals. For contrast-enhanced CT, 150-180 ml of IV contrast material, a mechanical power injector, and a scanning protocol that allowed completion of liver imaging within 2 min were used. Both unenhanced and contrast-enhanced CT scans were compared for detection and conspicuousness of hepatic lesions.Hepatic lesions were found in 34 patients. In 21 patients, all hepatic lesions seen on unenhanced scans also were apparent on contrast-enhanced scans. However, in 12 (57%) of 21 patients, lesions were more conspicuous and better defined on contrast-enhanced scans. The absolute number of lesions detected with each method of scanning differed in 12 patients. In four patients, the contrast-enhanced scan showed more lesions; in five patients, the unenhanced scan showed more lesions; and in three patients, administration of contrast material obscured some lesions shown on unenhanced scans and made others more conspicuous. If only a contrast-enhanced CT scan had been obtained, the presence of malignant hepatic neoplasm would have been missed in only one case (a patient with a single 2.8-cm metastasis from renal cell carcinoma).Bolus dynamic contrast-enhanced CT alone correctly showed the presence or absence of primary or metastatic hypervascular hepatic tumors in 100 of 101 cases. If the goal of CT examination is detection of hypervascular hepatic lesions, use of contrast-enhanced CT alone may be adequate and the addition of unenhanced scans is not cost-effective.

OBJECTIVE: The preoperative diagnosis of a primary appendiceal tumor can be difficult because of its rarity and the paucity of material in the radiology literature. The purpose of this study was to describe CT findings in six patients with primary mucinous cystadenocarcinoma of the appendix. CONCLUSION: When CT reveals a cystic mass with enhancing wall nodularity in the expected area of the appendix, especially in older patients, the possibility of primary mucinous cystadenocarcinoma should be considered.