Altered Gene Expression Profiles in Neural Stem Cells Derived from Duchenne Muscular Dystrophy Patients with Intellectual Disability

Intellectual disability (ID) is a neurodevelopmental disorder defined by below-average intelligence (intelligence quotient of <70) accompanied by adaptive behavior deficits. Defects in the functions of neural stem cells during brain development are closely linked to the pathogenesis of ID. To understand the molecular etiology of ID, we examined neural stem cells from individuals with Duchenne muscular dystrophy (DMD), a genetic disorder in which approximately one-third of the patients exhibit ID. In this study, we generated induced pluripotent stem cells from peripheral blood mononuclear cells from a normal individual and DMD patients with and without ID to identify ID-specific functional and molecular abnormalities. We found defects in neural ectoderm formation in the group of DMD patients with ID. Our transcriptome analysis of patient-derived neural stem cells revealed altered expression of genes related to the hippo signaling pathway and neuroactive ligand-receptor interaction, implicating these in the pathogenesis of ID in patients with DMD.

Altered Gene Expression Profiles in Neural Stem Cells Derived from Duchenne Muscular Dystrophy Patients with Intellectual Disability

Intellectual disability (ID) is a neurodevelopmental disorder defined by below-average intelligence (intelligence quotient of <70) accompanied by adaptive behavior deficits. Defects in the functions of neural stem cells during brain development are closely linked to the pathogenesis of ID. To understand the molecular etiology of ID, we examined neural stem cells from individuals with Duchenne muscular dystrophy (DMD), a genetic disorder in which approximately one-third of the patients exhibit ID. In this study, we generated induced pluripotent stem cells from peripheral blood mononuclear cells from a normal individual and DMD patients with and without ID to identify ID-specific functional and molecular abnormalities. We found defects in neural ectoderm formation in the group of DMD patients with ID. Our transcriptome analysis of patient-derived neural stem cells revealed altered expression of genes related to the hippo signaling pathway and neuroactive ligand-receptor interaction, implicating these in the pathogenesis of ID in patients with DMD.

Genome-Wide Identification and Classification of MicroRNAs Derived from Repetitive Elements

MicroRNAs (miRNAs) are known for their role in mRNA silencing via interference pathways. Repetitive elements (REs) share several characteristics with endogenous precursor miRNAs. In this study, 406 previously identified and 1,494 novel RE-derived miRNAs were sorted from the GENCODE v.19 database using the RepeatMasker program. They were divided into six major types, based on their genomic structure. More novel RE-derived miRNAs were confirmed than identified as RE-derived miRNAs. In conclusion, many miRNAs have not yet been identified, most of which are derived from REs.

Comparative Genomics of T-complex protein 10 like in Humans and Chimpanzees

Comparing 231 genes on chimpanzee chromosome 22 with their orthologous on human chromosome 21, we have found that 15 orthologs have indels within their coding sequences. It was rather surprising that significant number of genes have changed by indel, despite the shorter time since their divergence and led us hypothesize that indels and structural changes may represent one of the major mechanism of proteome evolution in the higher primates. Human T-complex protein 10 like (TCP10L) is a representative having indel within its coding sequence. Gene structure of human TCP10L compared with chimpanzee TCP10L gene showed 16 base pair difference in genomic DNA. As a result of the indel, frame shift mutation occurs in coding sequence (CDS) and human TCP10L express longer polypeptide of 21 amino acid residues than that of chimpanzee. Our prediction found that the indel may affect to dramatic change of secondary protein structure between human and chimpanzee TCP10L. Especially, the structural changes in the C-terminal region of TCP10L protein may affect on the interacting potential to other proteins rather than DNA binding function of the protein. Through these changes, TCP10L might influence gene expression profiles in liver and testis and subsequently influence the physiological changes required in primate evolution.

Comparative Study of Human and Chimpanzee Genome

No abstract available.

Diagnostic Usefulness and Limitation of Fine Needle Aspiration Cytology of Lymph Node: Analysis of 176 Cases Confirmed by Biopsy / 대한세포병리학회지

The accuracy of fine needle aspiration cytology(FNAC) of the lymph node was investigated through a review of 176 FNAC cases and the corresponding biopsies. We chose 157 FNAC cases after the exclusion of 19 inadequate ones. Sensitivity of malignancy was 94.0%, specificity 100%, false negativity 6.0%, and false positivity 0.0%. The overall diagnostic accuracy was 96.8%. Sensitivity of metastatic carcinoma was 98.0% and that of malignant lymphoma was 87.9%. False negative cases included one metastatic carcinoma and four malignant lymphomas. The aspirates of metastatic carcinoma with false negativity exhibited a diffuse smear of keratin debris without viable cells, which led to the difficulty in differentiation from benign epithelial cyst. The cases of malignant lymphoma with false negative diagnosis were two Hodgkin diseases, one Lennert's lymphoma, and one peripheral T cell lymphoma in the histologic sections. On the analysis of 39 cases of tuberculosis, 17 cases(43.6%) were diagnosed as tuberculosis, 4(10.3%) as granulomatous lymphadenitis, 3(7.7%) as necrotizing lymphadenitis, and 15(38.5%) as reactive hyperplasia or pyogenic inflammation. Sensitivity of tuberculosis was 53.9%. In conclusion, lymph node FNAC is an excellent non-invasive diagnostic tool for the diagnosis of metastatic carcinoma. The diagnostic accuracy of malignant lymphoma could be improved with flow cytometry or polymerase chain reaction for antigen receptor genes. For the FNAC diagnosis of tuberculosis, AFB stain, culture, and PCR would be helpful as adjuvant techniques.

Soft Tissue Perineurioma

Perineurial cells, which normally surround the nerve fascicles within a nerve, can be distinguished from Schwann cells by their immunoreactivity for epithelial membrane antigen (EMA) and lack of reactivity for S-100 protein. Perineurioma is a form of benign peripheral nerve sheath tumor (PNST) almost exclusively composed of perineurial cells. It is often difficult to differentiate this tumor from the other benign PNSTs or ectopic meningioma by histology alone. Immunohistochemical and electron microscopic studies are helpful for differential diagnosis. We recently experienced a case of soft tissue perineurioma in a 14-year-old girl. This tumor was presented as a 5.6 cm sized subcutaneous movable mass in the elbow. The well encapsulated soft tissue tumor consisted of spindle cells which have whorling and storiform patterns within the collagenous stroma. The spindle cells were stained positive for EMA but negative for S-100 protein, chromogranin, neuron-specific enolase or Leu-7. Ultrastructurally, they possessed long cytoplasmic processes with incomplete basal lamina, primitive intercellular junction and occasional pinocytotic vesicles.

Evaluation of the Left Atrial Size and Function in Addition to Analysis of the Mitral and Pulmonary Venous Flow Velocity in the Estimation of Left Ventricular Filling Pressures

BACKGROUND: Mitral and pulmonary venous(PV) flow velocity variables are being used for the indirect evaluation of left ventricular(LV) diastolic function. However, these flow velocities are influenced by age, loading conditions and other factors. This study was designed to evaluate usefulness of left atrial size and function in addition to the relation of mitral and PV flow velocity variables in the estimation of LV filling pressures. METHODS: Mitral and PV flow velocity variables. left artial size and function were assessed just before a cardiac catherization in 31 patients. According to the LV filling pressures, patients were divided into two subgroups and echocardiographic variables were compared. RESULTS: 1) LV end-diastolic pressure was related to the duration of reverse flow in the PV at atrial contraction(r=0.58) and difference in mitral and PV flow velocity duration at atrial contraction(r=0.54), and the similar findings were observed in other left ventricular filling pressures. 2) Left atrial size and volumes were greater in the subgroup of abnormal LV filling pressures(P < 0.05), but left atrial ejection fraction was not different between subgroups. CONCLUSION: In addition to variables of the mitral and PV flow velocities, left atrial size and volume may provide an additive value in the estimation of left ventricular filling pressures.