Pja2 Inhibits Wnt/β-catenin Signaling by Reducing the Level of TCF/LEF1

Ubiquitination of proteins plays an essential role in various cellular processes, including protein degradation, DNA repair, and cell signaling pathways. Previous studies have shown that protein ubiquitination is implicated in regulating pluripotency as well as fate determination of stem cells. To identify how protein ubiquitination affects differentiation of embryonic stem cells, we analyzed microarray data, which are available in the public domain, of E3 ligases and deubiquitinases whose levels changed during stem cell differentiation. Expression of pja2, a member of the RING-type E3 ligase family, was up-regulated during differentiation of stem cells. Wnt/β-catenin signaling is one of the most important signaling pathways for regulation of the self-renewal and differentiation of embryonic stem cells. Pja2 was shown to bind to TCF/LEF1, which are transcriptional factors for Wnt/β-catenin signaling, and regulate protein levels by ubiquitination, leading to down-regulation of Wnt signaling activity. Based on these results, we suggest that E3 ligase Pja2 regulates stem cell differentiation by controlling the level of TCF/LEF1 by ubiquitination.

Analyses of the TCR repertoire of MHC class II-restricted innate CD4+ T cells

Analysis of the T-cell receptor (TCR) repertoire of innate CD4+ T cells selected by major histocompatibility complex (MHC) class II-dependent thymocyte-thymocyte (T-T) interaction (T-T CD4+ T cells) is essential for predicting the characteristics of the antigens that bind to these T cells and for distinguishing T-T CD4+ T cells from other types of innate T cells. Using the TCRmini Tg mouse model, we show that the repertoire of TCRalpha chains in T-T CD4+ T cells was extremely diverse, in contrast to the repertoires previously described for other types of innate T cells. The TCRalpha chain sequences significantly overlapped between T-T CD4+ T cells and conventional CD4+ T cells in the thymus and spleen. However, the diversity of the TCRalpha repertoire of T-T CD4+ T cells seemed to be restricted compared with that of conventional CD4+ T cells. Interestingly, the frequency of the parental OT-II TCRalpha chains was significantly reduced in the process of T-T interaction. This diverse and shifted repertoire in T-T CD4+ T cells has biological relevance in terms of defense against diverse pathogens and a possible regulatory role during peripheral T-T interaction.

Pain Drawing in the Assessment of Nerve Root Compression in the Degenerative Spondylosis / 대한척추외과학회지

STUDY DESIGN: A retrospective study. OBJECTIVES: To explore the pattern of pain distribution in HNP and spinal stenosis with or without degenerative spondylolisthesis (DS), and to evaluate the diagnostic value of pain drawings in predicting the presence of a painful nerve root. SUMMARY OF LITERATURE REVIEW: The usefulness of pain drawing as a tool to predict the presence of painful nerve root compression is unclear. MATERIALS AND METHODS: Fifty-seven patients (27 HNP, 21 pure spinal stenosis, and 9 spinal stenosis with DS) with leg pain were recruited. The presence of painful nerve root compression was judged based on MRI and clinical findings. Each grid of the pain drawing is assigned an area code, and discriminant analysis was performed to explore indications of painful nerve root. Diagnostic values were evaluated by calculating sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). RESULTS: Pain distribution was characterized by a dermatomal pattern in HNP and variable in the spinal stenosis group. Paresthesia on the sole was extracted as a discriminant factor indicating painful compression of the S1 nerve root. In HNP, the sensitivity, specificity, PPV, and NPV of this factor were 62%, 100%, 100%, and 74% respectively. In the spinal stenosis group, they were 80%, 56%, 27%, and 93%, respectively. CONCLUSIONS: The pain drawing can help assess painful nerve root compression as well as confirm the pattern of pain distribution.

Osteoinduction Using Recombinant Bone Morphogenetic Protein-7 Gene / 대한정형외과학회잡지

PURPOSE: The aim of this study was to develop recombinant human Bone Morphogenetic Protein-7 (BMP7)-stable cells and recombinant human BMP7 adenoviruses (AdBMP7) for osteoinduction and osteoregeneration in musculoskeletal diseases. MATERIALS AND METHODS: The human BMP7 cDNA was amplified from a human osteosarcoma cell line, U2OS using a reverse transcription-polymerase chain reaction and cloned into a eukaryotic expression vector. The BMP7-stable HEK293 cells (HEK293/BMP7) were prepared by transfecting the recombinant BMP7 plasmid vector. The recombinant human BMP7 adenovirus (AdBMP7) was constructed using the AdEasy vector system. The BMP7 expression levels in HEK293/BMP7 and AdBMP7 were measured by activity staining for alkaline phosphatase in mouse C2C12 promyoblast cells. The BMP7-stable HEK293 cells, AdBMP7 itself, or AdBMP7-transduced human fibroblasts were injected into the subcutaneous tissues and the calf muscles of immunocompromised mice. The amount of ectopic bone formation was evaluated by radiographic and histological analyses. RESULTS: Ectopic bone formation was observed after injecting the BMP7-stable HEK293 cells with either the AdBMP7 itself or AdBMP7-transduced human fibroblasts into the subcutaneous tissues and calf muscles of immunocompromised mice. CONCLUSION: These results showed that HEK293/BMP7 cells and AdBMP7 have a significant potential for bone formation and the regeneration of various bone diseases.

Ovarian Mucinous Adenocarcinoma in 17-year-old Girl / 대한산부인과학회잡지

We experienced a case of malignant mucinous tumor of ovary developed in 17-year-oldnulliparous women and brief review of the case and its literature are presented.

A Case of Thanatophoric Dysplasia

No abstract available.

A Case of Lentigo Maligna Developed on the Sole / 대한피부과학회지

Lentigo maligna, a precancerous tumor arising from abnormal melanocytes, is a chronic, slowly progressive, pigmented lesion with a range of colors from pale tan to black and an irregular shape, The commonest location of lentigo maligna is the face during the sixth and seventh decades of life. Less frequently, the lesion occurs on an extrafacial area such as the hand or lower leg. In the late stage, lentigo maligna transforms into invasive malignant melanoma. A 50-year-old male patient had a well-defined, black pigmented patch on the right sole for 30 years. The histopathologic examination revealed numerous vacuolated melanocytes clusters at the dermo-epidermal junction with invasion of the epidermis. There was no evidence of dermal invasion by atypical melanocytes.

A Case of Primary Rhabdomyosarcoma in the Left Cerebello-Pontine Angle

The primary rhabdomyosarcoma of the brain is very rare. There are only 14 cases reported in the literatures till 1975, and the majority of them were arised in the cerebellum. The intracranial rhabdomyosarcomas may be originated from the multipotent mesenchymal cells of aberrent muscle tissue in the leptomeninges. The histological 3 types are adult pleomorphic, alveolar and embryonal type. The demonstration of cross-striation is confirmed for diagnosis of this tumor. All of these tumors tend to have a short clinical course, but the survival time seems to be slightly improved by surgical excision followed by radiotherapy. We have recently experienced one case of primary rhabdomyosarcoma in the left cerebellopontine angle of 9 year-old girl, which was confirmed by operation and complete autopsy.