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Hyun Ji Kim

Publications and source records attributed to Hyun Ji Kim.

3 recordsLinked to original sources

Microarray analysis of gene expression associated with extrapulmonary dissemination of tuberculosis.

OBJECTIVE: Although extrapulmonary organs are involved in 20% of patients with tuberculosis, the host genetic factors associated with the extrapulmonary dissemination of tuberculosis are not yet known. The aim of this study was to identify the host genetic factors associated with the extrapulmonary dissemination of tuberculosis by comparing gene expression profiles of patients who had recovered from extrapulmonary tuberculosis and those who had recovered from pulmonary tuberculosis. METHODS: Five patients from each group were enrolled. Total RNA was extracted from peripheral blood mononuclear cells that had been incubated for 48 h with whole lysate of Mycobacterium tuberculosis (H37Rv, 0.5 microg/mL). Gene expression profiles were acquired using the GeneChip array and its applied systems. Gene expression profiles from five patients with previous extrapulmonary tuberculosis and one pooled control sample from five patients with previous pulmonary tuberculosis were analysed and compared. Genes that were expressed concordantly in more than 80% of arrays and that showed more than twofold changes in at least one array among samples from patients who had recovered from extrapulmonary tuberculosis were identified. RESULTS: Compared with the control sample, the expression of 16 genes, including those for tumour necrosis factor (TNF)-alpha and cathepsin W, was increased, and the expression of 45 genes including that for TNF-receptor superfamily member 7 (TNFRSF7), was decreased in the extrapulmonary tuberculosis patients. The altered expression of the TNF-alpha, cathepsin W and TNFRSF7 genes was confirmed by quantitative RT-PCR. CONCLUSIONS: Altered expression of the genes for TNF-alpha, cathepsin W and TNFRSF7 may be risk factors for the extrapulmonary dissemination of tuberculosis in humans.

Adult↗

Ion channels: structural bioinformatics and modelling.

Ion channels are membrane proteins of key physiological and pharmacological importance. As is the case for many integral membrane proteins, X-ray structures are known for a few bacterial channels, yet structures of human homologues are required for analysis of channel-associated diseases and for drug design. Homology modelling can be used to help remedy this deficit. In combination with molecular dynamics simulations and associated calculations, modelling provides a powerful approach to understanding structure/function relationships in human ion channels. Modelling techniques have been applied to two classes of potassium channels: voltage-gated (Kv) and inward rectifier (Kir) channels. Kir channel models, based on the structure of the bacterial channel KcsA, have been used as a starting point for detailed simulation studies that have increased our understanding of ion permeation and selectivity mechanisms. The transmembrane domain of GluR0, a bacterial homologue of mammalian glutamate receptors, also may be modelled using the KcsA structure as a template. Models of the nicotinic acetylcholine receptor may be constructed in a modular fashion. The snail acetylcholine-binding protein provides a template for the extracellular ligand-binding domain. The transmembrane pore region can be modelled on the basis of NMR structures of the pore-lining M2 helix.

Amino Acid Sequence↗