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Kee Yang Chung

Publications and source records attributed to Kee Yang Chung.

At least 19 recordsLinked to original sources
PubMed2006

Clear cell basal cell carcinoma with sialomucin deposition.

Clear cell basal cell carcinoma (BCC) is a variant of BCC with a characteristic clear cell component that may occupy all or part of the tumor islands. Periodic acid-Schiff (PAS) staining for glycogen is variably positive, and mild deposition of sulfated mucin has been noted. However, to our knowledge, clear cell BCC with sialomucin deposition has not been reported. Here we report a case of clear cell BCC showing sialomucin deposition. The clear tumor cells stained with PAS and showed incomplete diastase-resistance. In addition, mucin staining with alcian blue was positive at pH 2.5 but not at pH 0.5.

Aged, 80 and over↗
PubMed2006

Developmental stage- and DNA damage-specific functions of C. elegans FANCD2.

In this study, we set out to investigate the role of Fanconi anemia complementation group D2 protein (FANCD2) in developmental stage-specific DNA damage responses in Caenorhabditis elegans. A mutant C. elegans strain containing a deletion in the gene encoding the FANCD2 homolog, FCD-2, exhibited egg-laying defects, precocious oogenesis, and partial defects in fertilization. The mutant strain also had a lower hatching rate than the wild-type after gamma-irradiation of embryos, but not after the irradiation of pachytene stage germ cells. This mutation sensitized pachytene stage germ cells to the genotoxic effects of photoactivated psoralen, as seen by a greatly reduced hatching rate and increased chromosomal aberrations. This mutation also enhanced physiological M-phase arrest and apoptosis. Taken together, our data reveal that the C. elegans FANCD2 homolog participates in the repair of spontaneous DNA damage and DNA crosslinks, not only in proliferating cells but also in pachytene stage cells, and it may have an additional role in double-stranded DNA break repair during embryogenesis.

Animals↗
PubMed2006

Scleroderma-like manifestation in a patient with primary systemic amyloidosis: response to high-dose intravenous immunoglobulin and plasma exchange.

A 54-year-old Korean male with scleroderma-like manifestation of primary systemic amyloidosis presented with firm cutaneous induration of face and distal extremities, subcutaneous induration of the trunk and proximal extremities, limited range of motion in all joints, hoarseness, and dysphagia. Monthly high-dose intravenous immunoglobulin (hdIVIg) was given (three treatments, each time administering 0.4 g/kg per day for five days), and both signs and symptoms began to improve. However, the quantitative analyses of serum protein did not improve. Therapeutic plasma exchange (TPE) was performed monthly to clear the elevated serum immunoglobulin, and after several treatments, their levels normalized and symptoms were maintained in the improved state for more than two years. To summarize, hdIVIg and TPE combination therapy may be used as a safe first-line treatment for patients with primary systemic amyloidosis presenting with symptomatic monoclonal gammopathy.

Amyloidosis↗
PubMed2006

Searching for aging-related proteins in human dermal microvascular endothelial cells treated with anti-aging agents.

Endothelial cells constitute an interface between blood and tissue and act as a medium for active interaction between plasma and the intracellular environment for homeostasis. Aging of endothelial cells plays a significant role in the pathophysiology of age-related vascular diseases; however, precise mechanisms for senescence have not been elucidated. Proteomics allows identification of protein structures, functions, and characteristics, and can be applied to the study of aging processes. Using cultured human dermal microvascular endothelial cells and two-dimensional proteomic mapping, we studied the effects of kinetin, epigallocatechin-3-gallate, all-trans-retinoic acid, and selenium on their senescence and searched for the aging-related proteins. The treatments resulted in 68 qualitative changes and 172 quantitative changes, and we were able to identify 46 spots among them. All of the agents indicated above induced changes in the expression of moesin, rho guanosine-5'-diphosphate-dissociation inhibitor, and actin, confirmed by immunoblotting and confocal laser microscopy. As these proteins were associated with cell cycle and cytoskeleton, immunoblotting of the proteins related to cell cycle was performed. Although practical significance remains to be confirmed by in vivo research, this fundamental discovery may provide a basis for understanding the mechanism of aging and age-related diseases.

Aging↗
PubMed2006

Caenorhabditis elegans as a screening tool for the endothelial cell-derived putative aging-related proteins detected by proteomic analysis.

Endothelial cells go through progressive pathophysiologic modification as cellular senescence progresses. In vitro, endothelial cell senescence is accompanied by failure of proliferation and by perturbations in gene and protein expressions. Moreover, this cellular senescence in culture has been proposed to reflect processes that occur in the organism in vivo and free radical theory is accepted to be the most plausible explanation for this process. We have screened proteins involved in both cellular senescence and reactive oxygen species induced condition using 2-D gel analysis and found that ubiquitin carboxyl terminal hydrolase L1, peroxyredoxin 2, peroxyredoxin 4, fatty acid binding proteins (FABPs), and 5'-AMP-activated protein kinase beta-1 subunit were candidate aging-related proteins. To evaluate in vivo function of these proteins, Caenorhabditis elegans (C. elegans) knock-down system using RNA interference was applied. Aging-specific expression of lipofucsin and the lifespan of knocked-down C. elegans were observed to assess the outcome. Interestingly, the inhibition of the genes led to short lifespan and earlier accumulation of lipofucsin with increasing age when compared with the wild type. These results suggest that the above genes may be related to cellular senescence process in determining the longevity in C. elegans and that gene inactivation renders animals susceptible to oxidative stress.

Animals↗
PubMed2006

Hypertrichosis lanuginosa acquisita associated with autoimmune hepatitis.

Hypertrichosis lanuginosa acquisita (HLA) is an unusual condition which is characterized by subtle and progressive development of multiple, long, thin, unmedullated hairs ("lanugo hairs") distributed preferentially on the face. Most cases are associated with malignant tumors or non-malignant condition such as porphyria cutanea tarda, AIDS, anorexia nervosa, thyrotoxicosis, or secondary to topical or systemic drugs (e.g. cyclosporine, phenytoin, diazoxide, minoxidil). We have recently experienced a rare case of hypertrichosis lanuginosa acquisita associated with autoimmune hepatitis. To our best knowledge, this is the first report of hypertrichosis lanuginosa acquisita associated with autoimmune hepatitis. Our observation expands the spectrum of diseases associated with this uncommon disorder.

Female↗
PubMed2006

Burn scars treated by pinhole method using a carbon dioxide laser.

Many patients with burn injuries have various complications and emotional problems due to scars. Although various modalities to improve burn scars have been attempted, such as excision of scars, skin grafts, laser abrasion and silicone product usage, the cosmetic outcomes have not been satisfactory for a large portion of patients. Herein, we describe two cases which showed satisfactory cosmetic results after treatment of burns scars with the pinhole method using a carbon dioxide (CO(2)) laser that allowed us to make deep, closely set holes reaching down to the upper dermis. A 20-year-old female patient with a scar on her neck and a 25-year-old female patient with a scar on her right forearm after burn injuries are presented. As early as only a few weeks after the treatment, the scars showed relaxation of contracture, reduction of wrinkles and improvement of texture and color compared to before the treatment. Treatment of burn scars with the pinhole method can be easily performed and results in dramatic improvement in scar quality with only a few side-effects.

Adult↗
PubMed2006

Histometric and histochemical analysis of the effect of trichloroacetic acid concentration in the chemical reconstruction of skin scars method.

BACKGROUND: Atrophic scars can be induced by various causes, including severely inflamed acne, chicken pox, and trauma. Many treatment modalities are used for reconstructing and improving the appearance of scars with various treatment results. OBJECTIVE: A recent report shows the clinical efficacy of the chemical reconstruction of skin scars (CROSS) method, which consists of the focal application of trichloroacetic acid (TCA) in a higher concentration. Histometric analysis of the CROSS method, however, has not yet been established. METHODS: In this study, five hairless mice were used to evaluate the effect of the CROSS method and to analyze the difference between the CROSS method and simple TCA application. RESULTS: Similar histologic changes were observed in the two methods, including epidermal and dermal rejuvenation with new collagen deposition. These changes, however, were more prominent in the CROSS method-treated areas, particularly when 100% TCA was used. CONCLUSION: The results of this study suggest that treatment of atrophic scars using the CROSS method is more effective than simple application of TCA in activating fibroblasts in the dermis and increasing the amount of collagen.

Administration, Topical↗
PubMed2005

Proteomic analysis of the proteins expressed by hydrogen peroxide treated cultured human dermal microvascular endothelial cells.

Reactive oxygen species (ROS) have been traditionally regarded as toxic by-products of aerobic metabolism. However, ROS also act as intracellular signaling molecules and can mediate phenotypes in vascular endothelial cells, which may be physiological or pathological in nature. To clarify the molecular mechanisms of ROS signaling, we examined hydrogen peroxide (H(2)O(2))-responsive proteins in cultured human dermal microvascular endothelial cells (HMVEC) using proteomic tools. Protein expression in HMVEC was studied after they had been exposed to low- and high-levels of H(2)O(2) for various times, and intracellular ROS production was examined by flow cytometer and UV spectrophotometer. Proteins obtained from dose- and time-dependent series were separated by two-dimensional gel electrophoresis and tentatively identified by matrix-assisted laser desorption-time of flight mass spectrometry, by matching the tryptic mass maps obtained with entries in the NCBI and Swiss-Prot protein sequence database. At least 163 proteins were changed by H(2)O(2), and 60 proteins were identified. Oxidative stress triggered dramatic change in the expression of proteins in primary microvessel endothelial cells, and their mapping to cellular process provided a view of the ubiquitous cellular changes elicited by H(2)O(2). These results could provide a framework for the understanding of the mechanisms of cellular redox homeostasis and H(2)O(2) metabolism in microendothelium environment in various biological processes as well as pathological conditions.

Amino Acid Sequence↗
PubMed2005

Variable patterns of positron emission tomography in the assessment of patients with extramammary Paget's disease.

Whole body 18 F-fluorodeoxyglucose (FDG) positron emission tomography was performed for staging in 7 extramammary Paget's disease patients and 4 tests showed mild FDG uptake at the primary sites. Histologically, all 4 tumors were found to be thicker than 2 cm. Among the 4 patients, 2 showed multiple hypermetabolic foci of skeletal metastasis and lymph node involvement.

Aged↗
PubMed2005

Fluorodeoxyglucose positron emission tomography in cutaneous squamous cell carcinoma: retrospective analysis of 12 patients.

BACKGROUND: Whole-body 18F-fluorodeoxyglucose positron emission tomography (FDG PET) has been used for whole-body imaging modality in detecting malignancy in clinical oncology. However, only a few reports of FDG PET in skin cancers have been described, except for melanoma and lymphoma. OBJECTIVE: To report on the usefulness of FDG PET as a baseline workup study for patients with cutaneous squamous cell carcinoma (SCC). METHODS: There were 12 cases of SCC (9 cases with high-risk SCC). Of the 12, FDG PET was performed for staging in 11 patients and for restaging in 1 patient 1 year after wide excision. RESULTS: Primary lesions were detected in nine cases (83.3%), lymph node involvement in three cases (25.0%), and distant. organ (lung) involvement in one case (8.3%). In one patient whose primary lesion was positive, stomach cancer with involvement of adrenal glands, omentum, and lymph nodes was incidentally detected. All of the patients with high-risk SCC showed FDG uptakes of the primary lesions, and the patients with FDG uptakes in lymph nodes and distant organ had high-risk SCC. CONCLUSION: There have been no comparative studies on the cost-effectiveness between sentinel lymph node biopsy and FDG PET in SCC patients. However, considering the noninvasiveness and thoroughness in checking the whole body, including distant organs, FDG PET may have clinical value as a baseline workup study for patients with high-risk SCC.

Aged↗
PubMed2005

Treatment of unusual vascular lesions: usefulness of sclerotherapy in lymphangioma circumscriptum and acquired digital arteriovenous malformation.

BACKGROUND: Sclerotherapy is used in venous malformations and hemangiomas, as well as chronic venous insufficiency and hemorrhoids. OBJECTIVE: To report on the usefulness of sclerotherapy in the treatment of unusual vascular lesions, such as lymphangioma circumscriptum and acquired digital arteriovenous malformation. METHODS: Two unusual cases were treated with a sclerosant, sodium tetradecyl sulfate. RESULTS: The patients were almost cleared with several treatments of sclerotherapy. CONCLUSION: Sclerotherapy can be recommended as an effective treatment method for unusual vascular lesions, such as lymphangioma circumscriptum and acquired digital arteriovenous malformation.

Adult↗
PubMed2004

The effects of Treponema pallidum on human dendritic cells.

Cell mediated immune responses play a prominent role in syphilis, which is caused by Treponema pallidum. The role of dendritic cells (DC) in the syphilitic infection is not well understood in human. In the present study, we studied interaction of T. pallidum with DC, generated from human peripheral blood mononuclear cells with GM-CSF and IL-4. After adding T. pallidum for 16 hours to immature DC at culture day 7, the change of surface antigens on DC was monitored by flow cytometry, the amount of IL-12 in culture supernatant of DC was measured by ELISA and T cell stimulatory capacity of DC was checked in mixed lymphocyte reaction (MLR). We have observed an efficient phagocytosis of T. pallidum by electron microscopy as early as 2 hours after addition of T. pallidum to DC. Interaction of DC with T. pallidum resulted in increased surface expression of CD83 which was proportionally increased according to the number of T. pallidum. Expressions of CD80, CD86 and HLA-DR on DC were slightly increased. The amount of IL-12 in the culture supernatant of DC was increased (1,099 pg/ml) after the addition of T. pallidum. T. pallidum-infected DC also displayed enhanced T cell stimulatory capacity in MLR. As seen from the above, we observed phagocytosis of T. pallidum by DC as early as 2 hours after addition of T. pallidum to DC and found that T. pallidum can stimulate DC maturation which mean that DC modulate an protective immune response during T. pallidum infection.

Cells, Cultured↗
PubMed2004

Expression of psoriasis-associated fatty acid-binding protein in senescent human dermal microvascular endothelial cells.

Aging is associated with the progressive pathophysiologic modification of endothelial cells. In vitro endothelial cell senescence is accompanied by proliferative activity failure and by perturbations in gene and protein expressions. Moreover, this cellular senescence in culture has been proposed to reflect processes that occur in aging organisms. In order to observe the changing patterns of protein expression in senescent human dermal microvascular endothelial cells (HDMECs), proteins obtained from both early- and late-passaged HDMECs were separated by two-dimensional electrophoresis, visualized by silver staining, and quantified by image processing. Proteins of interest were extracted by in-gel digestion with trypsin and quantified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), by searching the National Center for Biotechnology Information protein-sequence database. More than 2000 spots were detected by 2D electrophoresis within a linear pH range of 3-10. Twenty-two major differentially expressed spots were observed in serially passaged HDMECs and identified with high confidence by MALDI-TOF-MS. One of these spots was found to be a 14-15 kDa psoriasis-associated fatty acid-binding protein (PA-FABP) with high affinity for long-chain fatty acids. The expression of PA-FABP was confirmed to be elevated in senescent HDMECs (passage 20) by fluorescence-activated cell sorting (FACS), confocal laser microscopy, and by immunohistochemistry in aged human skin tissue. Our results suggest that the overexpression of FABP in cultured senescent HDMECs is closely related to skin aging.

Antibody Specificity↗
PubMed2004

Neurofibromatosis type 2 with multiple plexiform schwannomas.

Multiple plexiform schwannomas (PS) or neurilemmomas are very rare nerve sheath tumors, showing multiple schwannomas of the skin and other soft tissues, brain, or spinal cord with histopathologic characteristic of interwoven Antonio-A type tissues(1) but without other signs of neurofibromatosis type 2 (NF2). Neurofibromatosis type 2 is much less common than neurofibromatosis type 1 (NF1), with a symptomatic prevalence of 1 in 210,000,(2) and, to the authors' knowledge, only six cases of NF2 with multiple plexiform schwannomas have been reported in the literature.(3-5) We report a rare case of multiple cutaneous plexiform schwannomas associated with characteristic features of NF2 including bilateral acoustic neurilemomas and intracranial meningioma.

Brain Neoplasms↗