Ji-Hye Park

Staphylococcus aureus Colonization in Acute and Chronic Skin Lesions of Patients with Atopic Dermatitis

Background Staphylococcus aureus (SA) has peculiar abilities to colonize the skin in atopic dermatitis (AD) patients. Objective We sought to determine the colonization rates of SA in acute and chronic skin lesions of AD patients, to find any difference in colonization rates according to age and to find the influences of total immunoglobulin E (IgE) and eosinophil counts to the colonization of SA. Methods We evaluated the total IgE level and eosinophil counts, and cultured SA from the skin lesions of 687 AD patients (131 acute and 556 chronic skin lesions) and 247 control urticaria patients (July 2009 to November 2010; Samsung Medical Center Dermatology Clinic, Seoul, Korea). Results The SA colonization rates were 74%, 38% and 3% in acute, chronic skin lesions and control skin, respectively, and they were increased with age in AD patients. The colonization rate in chronic skin lesions was higher in the high IgE/eosinophilia groups as compared to the normal IgE/eosinophil groups. Conclusion The SA colonization rate was higher in AD patients and especially in acute lesions, and had a tendency to increase with age. As the colonization rates were only higher in the high IgE/eosinophilia groups of chronic skin lesions, we suggested that SA may invade the skin through barrier defects in acute skin lesions, but the colonization in chronic lesions may be orchestrated through many different factors.

Ribosomal Protein S3, a New Substrate of Akt, Serves as a Signal Mediator between Neuronal Apoptosis and DNA Repair

RPS3, a conserved, eukaryotic ribosomal protein of the 40 S subunit, is required for ribosome biogenesis. Because ribosomal proteins are abundant and ubiquitous, they may have additional extraribosomal functions. Here, we show that human RPS3 is a physiological target of Akt kinase and a novel mediator of neuronal apoptosis. NGF stimulation resulted in phosphorylation of threonine 70 of RPS3 by Akt, and this phosphorylation was required for Akt binding to RPS3. RPS3 induced neuronal apoptosis, up-regulating proapoptotic proteins Dp5/Hrk and Bim by binding to E2F1 and acting synergistically with it. Akt-dependent phosphorylation of RPS3 inhibited its proapoptotic function and perturbed its interaction with E2F1. These events coincided with nuclear translocation and accumulation of RPS3, where it functions as an endonuclease. Nuclear accumulation of RPS3 results in an increase in DNA repair activity to some extent, thereby sustaining neuronal survival. Abolishment of Akt-mediated RPS3 phosphorylation through mutagenesis accelerated apoptotic cell death and severely compromised nuclear translocation of RPS3. Thus, our findings define an extraribosomal role of RPS3 as a molecular switch that accommodates apoptotic induction to DNA repair through Akt-mediated phosphorylation.

Negative Regulation of p53 by the Long Isoform of ErbB3 Binding Protein Ebp1 in Brain Tumors

The ErbB3 binding protein Ebp1 has been implicated in a number of human cancers. Ebp1 includes 2 isoforms, p48 and p42, that exhibit different cellular activities. Here we show that the larger p48 isoform is transforming and that it promotes cell growth, clonogenicity, and invasion in human glioblastoma (GBM). P48 overexpression in GBM cells facilitated tumorigenesis and enhanced tumor growth in mouse xenograft models. Human GBM tissues displayed elevated levels of p48 compared with surrounding normal tissues or low-grade tumors. Notably, p48 levels were inversely correlated with poor prognosis in GBM patients. We determined that p48 binds to the p53 E3 ligase HDM2, enhancing HDM2-p53 association and thereby promoting p53 polyubiquitination and degradation to reduce steady-state p53 levels and activity. Together, our findings suggest that p48 functions as an oncogene by promoting glioma tumorigenicity via interactions with HDM2 that contribute to p53 downregulation.

An antimicrobial protein, lactoferrin exists in the sweat: proteomic analysis of sweat.

Abstract:  The main function of the eccrine gland has been considered to be thermoregulation. Recently, it has been reported that antimicrobial peptides including cathelicidin and dermcidin exist in the sweat. Lactoferrin is found in body fluids such as milk tears and saliva. It is known as a component of host defense against infection and inflammation. In this study, we explored whether lactoferrin is produced by eccrine glands, thereby establishing its potential role in the skin defense. By immunohistochemistry, lactoferrin was detected in eccrine glands of normal human skin. In Western blot analysis, lactoferrin was found in sweat and skin surface substances obtained from healthy volunteers. By proteomic analysis, lactoferrin and other antimicrobial peptides were detected in sweat. In addition, we measured the concentration of lactoferrin in sweat by enzyme‐linked immunosorbent assay. These findings suggest that lactoferrin may contribute to skin defense against infection through its secretion in sweat.

The presence and localization of onychodermis (specialized nail mesenchyme) containing onychofibroblasts in the nail unit: a morphological and immunohistochemical study

Lee D‐Y, Park J‐H, Shin H‐T, Yang J‐M, Jang K‐T, Kwon G Y, Lee K‐H & Shim J S 
(2012) Histopathology 61, 123–130

The incidence of leukotrichia in segmental vitiligo: implication of poor response to medical treatment

Background  In vitiligo, the melanocyte of the hair follicle is one of the major sources for repigmentation. Segmental vitiligo seems to be often associated with white hairs. However, in the case of small vellus hairs, it is often difficult or impossible to detect hair color. Thus, the real incidence of leukotrichia in segmental vitiligo has not been known.

The use of dermoscopy for the diagnosis of plantar wart

© 2008 The Authors JEADV 2009, 23, 702–738 Journal compilation

World Health Organization–European Organization for Research and Treatment of Cancer classification of cutaneous lymphoma in Korea: A retrospective study at a single tertiary institution

BACKGROUND The relative frequency and the clinicopathological characteristics of lymphoma may vary according to geography and ethnicity. Data are limited regarding the features of cutaneous lymphoma (CL) presented according to the World Health Organization (WHO) and the European Organization for Research and Treatment of Cancer (EORTC) classification (2005) in Korea. OBJECTIVE The study determined the relative frequency of CL in Korea and presented the clinical relevance of CL based on the WHO-EORTC classification. METHODS We reclassified the cases of CL collected over a 16-year period in a tertiary institution-based dermatologic setting in Korea. RESULTS In all, 164 cases were divided into 96 primary and 68 secondary CL. The group of primary CL consisted of T- and natural killer-cell lymphomas (84.3%), B-cell lymphomas (13.5%), and immature hematopoietic malignancies (2%). The Korean population presented with a higher rate of T-cell and natural killer-/T-cell CL and a lower rate of cutaneous B-cell lymphoma than Western countries. Compared with 2003 Korean data, the rate of mycosis fungoides was lower and the rate of nasal and nasal-type natural killer-/T-cell lymphomas was higher. LIMITATIONS This study was retrospective and based on a single-center experience. CONCLUSION As the relative frequency of lymphomas differs widely with geography and ethnicity, there is a need to collect more data to describe the epidemiologic characteristics in the Far East.

Scattered atypical melanocytes with hyperchromatic nuclei in the nail matrix: diagnostic clue for early subungual melanoma in situ.

The lack of highly specific clinical and histopathological criteria has contributed to the delay in diagnosis of subungual melanoma in situ in its early stages.

Is segmental vitiligo always associated with leukotrichia? Examination with a digital portable microscope.

Examination with a digital portable microscope Vitiligo is classified into nonsegmental and segmental types. The clinical features of segmental vitiligo differ markedly from those of nonsegmental vitiligo. Segmental vitiligo usually occurs early in life. It may spread rapidly, but is limited to one segment of the body and does not extend beyond the midline of the body. In one study, poliosis, i.e. a decrease or absence of melanin in the hair of the scalp, eyebrows, or eyelashes, was reported in 48.6% of cases of segmental vitiligo. When leukotrichia involves the eyebrow and scalp hair, it is noticeable; however, it is very difficult to detect small, thin, white hairs in other areas of the body with the naked eye. In this study, we examined the hair color in 20 patients with segmental vitiligo using a portable digital microscope (USB Microscope M2, Scalar Corporation, Tokyo, Japan). The patients were aged from 3 to 55 years. The duration of the condition ranged from 8 months to 10 years. Fourteen patients had facial lesions, two patients had neck lesions, two patients had trunk lesions, and two patients had arm lesions. Except for three patients with vitiligo involving the eyebrows, it was very difficult to evaluate the existence of white hairs with the naked eye. All patients showed white hairs in segmental vitiligo. Figure 1 shows white hairs by portable digital microscopy. In all patients, however, surrounding normal skin showed black hairs. In this study, with the help of portable digital microscopy, we found that all patients with segmental vitiligo had associated leukotrichia. The existence of white hairs in vitiligo lesions indicates that the condition may be resistant to medical treatment and may require surgical treatment, such as suctionblistered epidermal grafting. Enhancement with a ·30 video-microscope aids in the detection of the existence of leukotrichia in segmental vitiligo. Although the number of cases was not large, our data suggest that all patients with segmental vitiligo have associated leukotrichia. To confirm our result, further observations are necessary in larger numbers of patients with segmental vitiligo.