• Archives of Pharmacal Research
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• v.25 no.2
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• pp.208-213
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• 2002

The human polyomavirus JC virus is the etiologic agent of progressive multifocal leukoencephalopathy (PML). As the JC virus early promoter directs cell-specific expression of the viral replication factor large T antigen, transcriptional regulation constitutes a major mechanism of glial tropism in PML. It has been demonstrated that SV4O or JC virus large T antigen interacts with p53 protein and regulates many viral and cellular genes. In this study we founts that p53 represses the JC virus early promoter in both glial and nonglial cells To identify the cis-regulatory elements responsible for p53-mediated repression, deletional and site-directed mutational analyses were performed . Deletion of the enhancer region diminished p53-mediated transcriptional repression. However, point mutations of several transcription factor binding sites in the basal promoter region did not produce any significant changes. In support of this observation, when the enhancer was fused to a heterologous promoter, p53 red reduced the promoter activity about three fold. These results indicate that the enhancer region is important for tole repression of JC virus transcription by p53. Furthermore, coexpression of JC virus T antigen with a p53 protein abolished p53-mediated repression of the JC virus early promoter in non-glial cells, but not in glial cells. This finding suggests that T antigen interacts with p53 and regulates JC virus transcription in a cell-specific manner.

• Journal of Veterinary Clinics
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• v.33 no.2
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• pp.142-144
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• 2016

We report a case of Escherichia coli septicemia in a 6-year-old male bottlenose dolphin (Tursiops truncatus). Gross lesions included turbid reddish yellow ascites, fibrous adhesions of rectum and peritoneum, multifocal mucosal ulcers of rectum, and systemic petechiae. Multifocal necrosis with bacterial colonies was observed histologically in mucosal membrane of rectum and anus, and also in caudal mesenteric lymph node, inguinal lymph node, tracheobronchial lymph node, tonsil, spleen, liver, and lung. E. coli was isolated in pure culture from multiple organs including blood, spleen, mesenteric lymph node, liver, lung, and ascites. The E. coli was serotype O25. This case was diagnosed as a septicemia caused by E. coli serotype O25 associated with proctitis.

• Current Optics and Photonics
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• v.5 no.4
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• pp.421-430
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• 2021

The multifocal multiphoton microscopy (MMM) enables high-speed imaging by the concurrent scanning and detection of multiple foci generated by lenslet array or diffractive optical element. The MMM system mainly suffers from crosstalk generated by scattered emission photons that form ghost images among adjacent channels. The ghost image which is a duplicate of the image acquired in sub-images significantly degrades overall image quality. To eliminate the ghost image, the photon reassignment method was established using maximum likelihood estimation. However, this post-processing method generally takes a longer time than image acquisition. In this regard, we propose a novel strategy for rapid noise reduction in the MMM system based upon Monte-Carlo (MC) simulation. Ballistic signal, scattering signal, and scattering noise of each channel are quantified in terms of photon distribution launched in tissue model based on MC simulation. From the analysis of photon distribution, we successfully eliminated the ghost images in the MMM sub-images. If the priori MC simulation under a certain optical condition is established at once, our simple, but robust post-processing technique will continuously provide the noise-reduced images, while significantly reducing the computational cost.

• Archives of Craniofacial Surgery
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• v.20 no.3
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• pp.181-185
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• 2019

Intraosseous hemangioma is a rare, slow-growing, benign tumor of blood vessels. Primary hemangioma of the skull is a benign lesion that may appear as a palpable mass or accidentally detected during image evaluation. Simple radiography is the most commonly used technique to localize a lesion and computed tomography (CT) may help determine the effect of a lesion. We report a case of multifocal intraosseous calvarial hemangioma developed in the subgaleal plane of an elderly male patient. Ultrasonography examination revealed hyperechoic striated septae parallel to the skin and discontinuity of the focal cortex, however, the underlying bone cortex appeared relatively intact. No significant flow is observed on Doppler ultrasonography. Based on these evaluations, the mass was interpreted by a radiologist as a subgaleal lipoma. This case highlights the importance of additional CT examination in a patient presenting with a scalloping sign of the underlying calvarium. Clinicians also should be aware of the possibility of intraosseous calvarial hemangiomas in lesion. Furthermore, the proper choice of congenital vascular malformation term is still quite confusing with misconception present in the literature.

• Kosin Medical Journal
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• v.33 no.3
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• pp.454-462
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• 2018

A 54-year-old man, suffering from severe headache and ophthalmoplegia after undergoing endoscopic sinus surgery was referred to a tertiary hospital. Computed tomography (CT) revealed soft tissue density lesions in the left sphenoid sinus. The internal carotid artery was shown to be occluded in brain magnetic resonance imaging (MRI) scans without any other cerebral lesion. Endoscopic view of left nasal cavity shows whitish hyphae in the ethmoid and the sphenoid sinuses. We diagnosed him with cavernous sinus syndrome caused by mucormycosis and conducted endoscopic sinus surgery to remove remaining lesions and decompress orbit and optic nerves. After the revision surgery the patient's headache and ophthalmoplegia were improved. However, multifocal cerebral infarctions were newly discovered in a postoperative CT scan. We experienced a case of mucormycosis of sphenoid sinus resulting in occlusion of internal carotid artery and multifocal cerebral infarction, and report it with a brief review of these disease entities.

• Korean Journal of Veterinary Service
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• v.43 no.4
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• pp.251-256
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• 2020

Two suckling piglets, 4 days and 10 days of age, showed lethargy and dyspnea after birth and mortality had been increased after incoming gilts from breeding farm. At necropsy, the lungs showed diffuse fail to collapse with rubbery consistency, edematous dilatation of interlobular septa, and lobular consolidation with purple red color. Heart was diffuse pale in color and had several irregular linear-shaped macules or patches. Histopathologically, diffuse interstitial pneumonia with the proliferation of type II pneumocytes was present in the lungs of 2 piglets. Alveolar lumens contained necrotic cellular debris derived from neutrophils and macrophages. Multifocal hemorrhage and necrotizing pneumonia with protozoan tachyzoites were observed in the lungs. Severe multifocal to confluent necrotic myocarditis, necrotic encephalitis, and necrotic adrenalitis with intralesional protozoan tachyzoites were observed in piglets. According to immunohistochemical analysis (IHC), Toxoplasma (T.) gondii tachyzoites antigens were confirmed in lung, heart, brain, and adrenal gland. And porcine reproductive and respiratory syndrome virus (PRRSV) antigens were also detected in the cytoplasm of macrophages in lungs using IHC. Based on the gross, histopathologic and immunohistochemical features, two suckling piglets were diagnosed as co-infection of T. gondii and PRRSV.

• Journal of the Korean Society of Radiology
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• v.84 no.5
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• pp.1163-1168
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• 2023

Abscess formation due to Candida albicans infection is extremely rare. Radiological diagnosis of an atypical abscess at an uncommon site is challenging. In this study, we present a case of insidious onset multifocal chest wall and spinal abscess after candidemia in a young woman in the intensive care unit due to postpartum bleeding.

• Korean Journal of Optics and Photonics
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• v.33 no.1
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• pp.28-34
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• 2022

We study through computational simulation the focal performance of an infrared (IR) Fresnel lens, composed of a multilayer-graphene zone plate formed under a graphene electrode. Here the Fermi level E_F of the patterned multilayer graphene is adjusted by the overlying graphene electrode. The Fresnel lens effect, with respect to the reflectance contrast between the graphene electrode and the 8-layer graphene zone plate placed on a glass substrate, has been analyzed over a broad wavelength range from 4 to 30 ㎛. As the optimal wavelength of 8 ㎛ (considering the reflectance and the reflectance-contrast ratio) is incident upon the Fresnel lens with a focal length of 240 ㎛, the focal intensity is enhanced by a factor of 4.3 as the E_F of multilayer graphene increases from 0.4 eV to 1.6 eV, and is improved by a factor of 5.8 as the number of graphene layers increases from two to eight. As a result, an all-graphene-based IR Fresnel zone-plate lens, exhibiting multifocal function (240 ㎛ and 360 ㎛) according to the selected E_F, is proposed as an ultrathin lens platform.

• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2003.10a
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• pp.49-49
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• 2003

PMWS is characterised by weight loss and dyspnea combined with pathological findings of interstitial pneumonia and generalized enlarged lymph nodes. Typical histological lesions include multifocal granulomatous pneumonia, and lymphocyte depletion and multinucleated giant cell formation in lymph nodes[1,2]. (omitted)

• Journal of Veterinary Clinics
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• v.18 no.4
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• pp.482-486
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• 2001

A seven year old dog with a history of vomiting for one month, icterus for one week yellowish urination for a few weeks, weight loss (1.5 kg loss/wk), and swelling of submandibular, prescapular, axillary, inguinal and popliteal lymph nodes and then a 3 year old dog with mild vomiting history and multifocal mass(neck, shoulder, mammary glands) were diagnosed as lymphoma by radiography, ultrasonography and ultrasound-guided fine needle aspiration and died all thereafter without any chemotherapeutical treatment.