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Biomedical subjects

J B Kim

Publications and source records attributed to J B Kim.

At least 91 records · Page 5Linked to original sources
PubMed1995

Dual DNA binding specificity of ADD1/SREBP1 controlled by a single amino acid in the basic helix-loop-helix domain.

Adipocyte determination- and differentiation-dependent factor 1 (ADD1), a member of the basic helix-loop-helix (bHLH) family of transcription factors, has been associated with both adipocyte differentiation and cholesterol homeostasis (in which case it has been termed SREBP1). Using PCR-amplified binding analysis, we demonstrate that ADD1/SREBP1 has dual DNA sequence specificity, binding to both an E-box motif (ATCACGTGA) and a non-E-box sequence previously shown to be important in cholesterol metabolism, sterol regulatory element 1 (SRE-1; ATCACCCCAC). The ADD1/SREBP1 consensus E-box site is similar to a regulatory sequence designated the carbohydrate response element, defined by its ability to regulate transcription in response to carbohydrate in genes involved in fatty acid and triglyceride metabolism in liver and fat. When expressed in fibroblasts, ADD1/SREBP1 activates transcription through both the carbohydrate response E-box element and SRE-1. Substitution of an atypical tyrosine in the basic region of ADD1/SREBP1 to an arginine found in most bHLH protein causes a restriction to only E-box binding. Conversely, substitution of a tyrosine for the equivalent arginine in another bHLH protein, upstream stimulatory factor, allows this factor to acquire a dual binding specificity similar to that of ADD1/SREBP1. Promoter activation by ADD1/SREBP1 through the carbohydrate response element E box is not sensitive to the tyrosine-to-arginine mutation, while activation through SRE-1 is completely suppressed. These data illustrate that ADD1/SREBP1 has dual DNA sequence specificity controlled by a single amino acid residue; this dual specificity may provide a novel mechanism to coordinate different pathways of lipid metabolism.

3T3 Cells↗
PubMed1995

Pharmacokinetics of theophylline: effects of hepatic fibrosis in rats induced bile duct ligation.

This experiment was performed to evaluate the usefulness of an experimental fibrosis model by bile duct ligation as a pharmacokinetic model of a disease state. First, experimental liver fibrosis was produced by bile duct ligation. At 4 weeks postoperation, a fibrotic condition was characterized by measurement of the aminoterminal procollagen type III peptide (PIIINP) level in serum, total collagen content in liver and light microscopic histology. Four weeks after bile duct ligation there was an increase in total collagen content of the liver to 430% of the initial values, accompanied by an increase of serum-PIIINP (385%). Secondly, we examined the pharmacokinetics of theophylline in the fibrotic rat induced by bile duct ligation. An i.v. dose of 8 mg of theophylline per kg of body weight was administered, and the levels of theophylline in serum were assayed by high performance liquid chromatography. The area under the serum concentration-time curve of theophylline was increased significantly in fibrotic rats compared with that of the control, and the total clearance of drug in fibrotic rats was low, averaging 22.6 mg/kg/h vs. 36.1 and 60.9 ml/kg/h in the control and the normal rat, respectively. However, the value of distribution during the beta-phase was not significantly affected by experimental liver fibrosis.

Alanine Transaminase↗
PubMed1995

Reliability and validity of the cognitive impairment diagnosing instrument (CIDI) in the elderly.

The reliability and validity of the Cognitive Impairment Diagnosing Instrument (CIDI) were studied in 67 nursing home elderly subjects and 251 elderly psychiatric patients. Its possible highest score is 77 and covers 10 subscales: short-term memory, long-term memory, concentration/calculation, abstract thinking, judgement, memory registration, higher cortical functions, orientation in time, orientation in place and object naming. Test-retest correlations were between 0.827 and 0.990 for the subscale scores and 0.984 for the total score. Inter-tester kappas for each item ranged from 0.200 to 1.000 with a mean of 0.698. Concordance rates were between 50.0 and 100.0% with a mean of 87.2%. Cronbach's alphas for the items of the individual subscales ranged from 0.702 to 0.915. Inter-subscale and subscale-total correlations ranged from 0.503 to 0.820 with a mean of 0.684 and from 0.721 to 0.883, respectively. Cronbach's alpha of the subscales was 0.934. Sensitivity and specificity were 93.3% and 93.8% at the cut-off point of 57.0/57.5 for dementia. Subscale and total scores were significantly different between the demented and non-demented. The total CIDI score was significantly correlated with scores of the Blessed Dementia Rating Scale and the Korean version of the Mini-Mental State Examination.

Aged↗
PubMed1995

A human case of invasive fascioliasis associated with liver abscess.

A 56 year-old Korean housewife/farmer/goat keeper suffered from right upper quadrant pain and fever with chills. In the abdominal sonogram and computerized tomography, multiple, 2-3 cm, irregular shaped cavities were observed in the right lobe of liver. A liver biopsy revealed extensive central necrosis with Characot-Leyden crystals surrounded by palisading histiocytes, eosinophil-rich inflammatory infiltration. Worm was not observed. However, the serologic test for Fasciola-specific IgG antibody by micro-ELISA was positive. Prior antibody levels did not differ and eosinophilia persisted 6 and 16 months after praziquantel treatment although the cavitary lesions in the liver disappeared 6 months after the treatment. Reported herein is a human case of invasive fascioliasis diagnosed clinically by a combination of radiological, histopathological and serological studies.

Animals↗
PubMed1995

Detection of antibodies to human melanoma cell in vitiligo by western blot analysis.

Vitiligo is a disease in which melanocytes are selectively destroyed. The disease is thought to be an autoimmune process being there are antibodies to pigment cells in the sera of patients and animals with vitiligo. In the present study, sera from vitiligo patients were examined for reactivity with the human melanoma cell line, SK-Mel-28, by Western blot analysis of solubilized membrane antigens of these cells to identify the pigment cell antigens defined by antibodies in the patients with vitiligo. Antibody reactivity to human melanoma cells (SK-Mel-28) was investigated in 14 patients with vitiligo, and 16 with normal control individuals. Antibodies to the 116-113, 60, 40 KD antigens were associated with vitiligo being present in 79%, 86%, and 43% respectively of the patients with vitiligo, but in only 6%, 38% and 6% of the normal controls. In contrast, antibodies to the 160-155, 78 and 64 KD antigens were equally common in vitiligo and in normal individuals. The results suggest that autoreactivity to pigment cells occurs more commonly in patients with vitiligo than in the normal control and high autoreactivity to pigment cells in the vitiligo sera might be an impertinent epiphemenon to destroyed pigment cell.

Antibodies, Neoplasm↗
PubMed1994

Isolation of isoguanosine from Croton tiglium and its antitumor activity.

This paper describes the isolation of isoguanosine from Croton tiglium L. and its cytotoxic effect against several tumor cell lines in culture and newly reports that isoguanosine has an antitumor activity against implanted S-180 ascitic tumor mice. Isoguanosine is effective at the dose of 24 mg/kg/day x 5, with T/C value of 168%. Isoguanosine inhibits the growth of S-180 and Ehrlich solid tumor in mice at the optimal doses of 96 mg/kg/day x 12 and 48 mg/kg/day x 12, with 1-T/C values of 65% and 60%, respectively.

Adenosine↗
PubMed1994

Differential expression of protein kinase C genes in cultured mast cells derived from normal and mast-cell-deficient mice and mast cell lines.

We investigated the expression of mRNA of protein kinase C (PKC) isozymes (alpha, beta, gamma, delta, epsilon, xi, and eta) in cultured mast cells (CMC) derived from normal (+/+) mice, CMC derived from genetically mast-cell-deficient (W/W, Wv/Wv, and mi/mi) mice, and murine mast cell lines (IC2, MC9, and P-815) by Northern blotting. In +/+ CMC, abundant expression of PKC delta and moderate expression of PKC alpha and beta was observed, while other PKCs (types gamma, epsilon, xi, and eta) were not detected. In vivo expression of PKC delta was demonstrated in the skin by in situ hybridization. In mast cell lines, the expression pattern of PKC isozymes was similar to that of +/+ CMC, except that the expression of PKC eta was detected in the IC2 cell line. The expression levels of PKC delta in CMC derived from c-kit-deficient mutants, W/W, Wv/Wv, and mi/mi, were lower than that of +/+ mice. These results indicate that PKC delta is the main isozyme in various types of murine mast cells and also suggest that the reduced level of PKC delta expression in mutant mice may be caused by a deficit in the signal transduction system through c-kit receptor.

Animals↗
PubMed1993

Calcitonin gene-related peptide-like immunoreactive (CGRPI) elements in the circadian system of the mouse: an immunohistochemistry combined with retrograde transport study.

This study was based on immunohistochemical detection of calcitonin gene-related peptide-like immunoreactive (CGRPI) neurons and fibers in the suprachiasmatic nucleus (SCN) and intergeniculate leaflet (IGL) of the mouse. CGRPI neurons and fibers were found within the ventrolateral part of the SCN, in the whole extent of IGL and sparsely distributed in ventral lateral geniculate body. The presence of CGRPI structures in the SCN and IGL of the mouse further supports the hypothesis of differences in the content of neuroactive substances in the circadian clock between mammalian species. Fluorogold retrograde transport combined with CGRP immunofluorescence demonstrates that CGRPI neurons in the IGL constitute a part of IGL reciprocal connections.

Animals↗
PubMed1993

Expression of RAD4 gene of Saccharomyces cerevisiae that can be propagated in Escherichia coli without inactivation.

The RAD4 gene of Saccharomyces cerevisiae, which is essential for the nucleotide excision repair, was isolated from a yeast genomic library and the expression of this gene has been investigated. RAD4 mRNA was approximately 2.3 kb and di not contain intervening sequence, as determined by S1 nuclease mapping and Northern blot analysis. Transcription start site was located at 48 bp upstream of the ATG initiation codon. RAD4 gene is not induced by UV light damages as indicated by the absence of change in mRNA level after UV exposure in wild type yeast cells. The size of Rad4 protein overexpressed in Escherichia coli was found to be 89 kDa by SDS-PAGE. This is consistent with the size of the gene's ORF, which encodes 730 amino acids with the calculated molecular weight of 84456. The RAD4 protein contains many potential kinase dependent phosphorylation sites and its C-terminus is highly acidic like other DNA repair proteins of S. cerevisiae.

Cloning, Molecular↗
PubMed1993

Profile of Fos-like immunoreactivity induction by light stimuli in the intergeniculate leaflet is different from that of the suprachiasmatic nucleus.

Light stimuli induce Fos-like immunoreactivity (FLI) in suprachiasmatic nucleus (SCN) and intergeniculate leaflet (IGL). Short pulses of light stimuli that synchronize the circadian rhythms induce FLI in SCN. The characteristics of light induction of FLI in the IGL were studied using immunohistochemistry. In the IGL, at least 2 h of sustained light stimuli were necessary to show an increase of FLI. This FLI persisted while the light was turned on. FLI induction in the IGL by light stimuli was not circadian time specific response. These findings imply that the functional significance of Fos activation on circadian rhythms and mechanism of FLI induction in IGL would be different from that in SCN.

Animals↗
PubMed1993

ADD1: a novel helix-loop-helix transcription factor associated with adipocyte determination and differentiation.

DNA-binding proteins containing the basic helix-loop-helix (bHLH) domain have been implicated in lineage determination and the regulation of specific gene expression in a number of cell types. By oligonucleotide screening of an adipocyte cDNA expression library, we have identified a novel member of the bHLH-leucine zipper transcription factor family designated ADD1. ADD1 mRNA is expressed predominantly in brown adipose tissue in vivo and is regulated during both determination and differentiation of cultured adipocyte cell lines. ADD1 can function as a sequence-specific transcriptional activator in that it stimulates expression of a chloramphenicol acetyltransferase vector containing multiple ADD1 binding sequences but is unable to activate the myosin light-chain enhancer, which contains multiple binding sites for another bHLH factor, MyoD. ADD1 can also activate transcription through a binding site present in the 5'-flanking region of the fatty acid synthetase gene which is expressed in a differentiation-dependent manner in adipose cells. These data suggest that ADD1 plays a role in the regulation of determination- and differentiation-specific gene expression in adipocytes.

Adipose Tissue↗
PubMed1992

A transient rise in intracellular Ca2+ is a precursor reaction to the zona pellucida-induced acrosome reaction in mouse sperm and is blocked by the induced acrosome reaction inhibitor 3-quinuclidinyl benzilate.

The acrosome reaction induced by the zona pellucida in mouse sperm has been shown to proceed in two stages experimentally distinguishable by the fluorescent probe chlortetracycline. Entry into the first stage of sperm bound to isolated, structurally intact zonae pellucidae is blocked by the compound 3-quinuclidinyl benzilate. In this study, we show, utilizing the fluorescent Ca2+ indicator fluo-3, that the first stage of the zona-induced acrosome reaction is characterized by an increase in intracellular Ca2+, followed by a decrease as the acrosome reaction proceeds. This calcium transient is completely suppressed by 3-quinuclidinyl benzilate. We conclude that the Ca2+ transient is induced by the zona pellucida and is required for the zona-induced acrosome reaction. Blockage of this sperm intracellular Ca2+ transient provides a mechanism for the inhibitory action of 3-quinuclidinyl benzilate on the zona-induced acrosome reaction in mouse sperm.

Acrosome↗
PubMed1992

Changes in Esterification of the Uronic Acid Groups of Cell Wall Polysaccharides during Elongation of Maize Coleoptiles.

Cell walls of grasses have two major polysaccharides that contain uronic acids, the hemicellulosic glucuronoarabinoxylans and the galactosyluronic acid-rich pectins. A technique whereby esterified uronic acid carboxyl groups are reduced selectively to yield their respective 6,6-dideuterio neutral sugars was used to determine the extent of esterification and changes in esterification of these two uronic acids during elongation of maize (Zea mays L.) coleoptiles. The glucosyluronic acids of glucuronoarabinoxylans did not appear to be esterified at any time during coleoptile elongation. The galactosyluronic acids of embryonal coleoptiles were about 65% esterified, but this proportion increased to nearly 80% during the rapid elongation phase before returning to about 60% at the end of elongation. Methyl esters accounted for about two-thirds of the total esterified galacturonic acid in cell walls of unexpanded coleoptiles. The proportion of methyl esters decreased throughout elongation and did not account for the increase in the proportion of esterified galactosyluronic acid units during growth. The results indicate that the galactosyluronic acid units of grass pectic polysaccharides may be converted to other kinds of esters or form ester-like chemical interactions during expansion of the cell wall. Accumulation of novel esters or ester-like interactions is coincident with covalent attachment of polymers containing galactosyluronic acid units to the cell wall.

Journal Article↗
PubMed1991

A gene in Schizosaccharomyces pombe analogous to the RAD4 gene of Saccharomyces cerevisiae.

A gene, analogous to the RAD4 gene, which is required for nucleotide excision repair in Saccharomyces cerevisiae, also exists in Schizosaccharomyces pombe. RNA isolated from wild type S. pombe cells strongly cross-hybridized with the 1.2 kb PvuII DNA fragment of the S. cerevisiae RAD4 genomic clone (pPC1). Chromosomal DNA isolated from S. pombe had similar restriction patterns to those from S. cerevisiae, as determined by Southern blot analysis. Two species of mRNA, 3.1 and 1.8 kb, were identified by Northern hybridization. The level of these transcripts did not increase upon UV-irradiation, suggesting that the RAD4-like gene in S. pombe is not UV-inducible.

DNA Damage↗
PubMed1990

Characterization of RAD4 gene required for ultraviolet-induced excision repair of Saccharomyces cerevisiae propagated in Escherichia coli without inactivation.

The previously isolated RAD4 gene designated as pPC1 from the genomic library of Saccharomyces cerevisiae (Yoon et al., 1985, Korean J. Genetics 7, 97-104) appeared to propagate in Escherichia coli and yet retained its complementing activity to rad4 mutants without inactivation. The subcloned RAD4 gene was found to be localized within a 2.5 kb DNA fragment flanking Bg1II and BamHI sites in the insert DNA, and was shown to have the same restriction map as a yeast chromosomal DNA, as determined by Southern hybridization. Tetrad analysis and pulse-field chromosome mapping have revealed that the cloned RAD4 gene can be mapped and integrated into the yeast chromosome V, the actual site of this gene. DNA-tRNA hybridization has shown that the isolated RAD4 gene did not contain a suppressor tRNA gene. These results have indicated that the pPC1 is a functional RAD4 gene playing a unique role involved in the nucleotide excision repair of yeast without any genetic change during amplification in E. coli.

Chromosome Mapping↗
PubMed1990

[A study on the chairside dental assistants in the Republic of Korea].

It is recommended that the chair-side dental assistant should be utilized in order to increase the production of dental health care by World Health Organization. In the Republic of Korea, there was no chair-side dental assistant by legally. So the authors investigated and discussed for the development of chair-side dental assistant in Korea. Obtained results were as follows 1. In order to increase the production of dental health care chair-side dental assistants should be developed. 2. Institution of chair-side dental assistant will be established legally. 3. Trained chair-side dental assistant will be positioned in dental clinics for dentist and health centers for dental public health.

Dental Assistants↗