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Biomedical subjects

J I Kim

Publications and source records attributed to J I Kim.

At least 91 records · Page 5Linked to original sources
PubMed1999

Role of multicolor fluorescence in situ hybridization (FISH) in simultaneous detection of probe sets for chromosome 18, X and Y in uncultured amniotic fluid cells.

Major aneuploidies diagnosed prenatally involve the autosomes 13, 18, and 21, and sex chromosomes. Fluorescence in situ hybridization (FISH) allows rapid analysis of chromosome copy number in interphase cells. The purpose of this study was to evaluate the role of multicolor fluorescence in situ hybridization in simultaneous detection of probe sets for chromosome 18, X, and Y in uncultured amniotic fluid cells as a safer alternative method for aneuploidy detection prenatally. Fifty amniotic fluid samples were analyzed by FISH and standard cytogenetics. Mean time to obtain results was three days for fluorescence in situ hybridization and 20 days for karyotype. Fluorescence in situ hybridization was informative in 43 samples (86%), and within this group, two aneuploidies were correctly identified. This evaluation demonstrates that FISH with X, Y, and 18 alpha satellite DNA probes could accurately and rapidly detect aneuploidies involving these chromosomes and could be used in any prenatal clinical laboratory.

Amniocentesis↗
PubMed1999

Adenosquamous carcinoma of the prostate.

An unusual adenosquamous carcinoma originating in the prostate of a 73-year-old man is described. The histological finding showed a well differentiated squamous cell carcinoma admixed in an adenocarcinomatous area. A transitional area of 2 carcinomatous elements was also noted. Seven months prior to the development of this lesion, a diagnosis of adenocarcinoma had been established by transurethral resection of the prostate and the patient had been treated with bilateral orchiectomy. This is the first case of adenosquamous carcinoma of the prostate reported in Korea. The pathogenesis and previous reports of this lesion will be discussed.

Aged↗
PubMed1999

The Korean collaborative study on 11,000 prenatal genetic amniocentesis.

Since amniocentesis made prenatal diagnosis feasible in 1967, the method has been remarkably instrumental in obstetrical practice. A recent study conducted between 1980 and 1997 collected 11,000 amniocentesis procedures done at 10 university hospitals and tertiary centers in Korea. The study indicated that the use of amniocentesis on patients has increased steadily since 1980; however, the number has increased sharply for patients in the mid 1990's. In the 1980's, amniocentesis had been used primarily for patients in advanced maternal age groups (at least 35 years or older). In 1995, amniocentesis had been implemented for the detection of abnormal serum markers (37.6%), and by 1997, amniocentesis was involved in such diagnosis even more frequently (44.8%). Of the total number of uses, 270 (2.5%) involved the detection of chromosomal anomaly. In autosomal disorders, 96 Down syndrome, 33 Edward syndrome, and 6 Patau syndrome were diagnosed. In sex chromosomal anomaly, 10 Turner syndrome, and 10 Klinefelter syndrome were diagnosed. Added to that, 83 translocations, and 15 mosaicisms were diagnosed. Of the 322 cases with abnormal ultrasonographic findings, 21 (6.5%) resulted in chromosomal anomaly. The use of genetic amniocentesis as a prenatal diagnostic test for Korean women has risen 10-fold between 1988 and 1998. As stated earlier, amniocentesis had earlier been used primarily for those in advanced maternal age groups. Today, maternal serum markers and highly sensitive ultrasonic technology can detect many fetal anomalies which eventually necessitate amniocentesis.

Adult↗
PubMed1998

Induction of differentiation of the human histocytic lymphoma cell line U-937 by hypericin.

Hypericin, a photosensitizing plant pigment, was found to be a potent inducer of differentiation of human myeloid leukemia U-937 cells. At a concentration of 0.2 microM, hypericin exhibited 50% growth inhibition. An effect on cell differentiation by hypericin was assessed by its ability to induce phagocytosis of latex particles, and to reduce nitroblue tetrazolium (NBT). Approximately 51% of 0.2 microM hypericin-treated cells were stained with NBT and 63% showed phagocytic activity. In order to establish whether hypericin induces differentiation of U-937 cells to macrophage or granulocyte, esterase activities and cell sizes were measured. When U-937 cells were treated with 0.2 microM and 0.15 microM of hypericin, the alpha-naphthyl acetate esterase activity was increased by 38.4% and 48.1%, respectively, but naphthol AS-D chloroacetate esterase activity was not influenced. The size of hypericin-treated cells in terms of cell mass was larger than that observed in untreated cells as determined by flow cytometry. Protein kinase C (PKC) inhibitor, NA-382, decreased the NBT reducing activity of hypericin, whereas a cAMP-dependent protein kinase A (PKA) inhibitor, H-89, did not show any influence on the differentiation. These results indicate that hypericin triggers differentiation toward monocyte/macrophage lineage by PKC stimulation.

Anthracenes↗
PubMed1998

Thymic epithelial tumor progression in an SV40T transgenic mouse model. Cortical thymoma-thymic carcinoma sequence.

There have been several reports that thymoma in human is a progressive disease, and that thymoma and thymic carcinoma form a continuum. We established a stable line of SV40T transgenic mice, which consistently produced thymic epithelial tumours progressing to thymic carcinoma within a predictable time span. Using this animal model and a morphological approach, thymic epithelial tumour progression was studied with reference to sequential changes at different time points in animals aged from 3 to 32 weeks. At all ages, SV40T was expressed in the nuclei of thymic epithelial cells; in these transgenic mice we observed the entire spectrum from cortical type thymoma to thymic carcinoma. Thymic size tended to increase with ageing in SV40T TG mice. While younger mice had predominantly cortical (organoid) or cortical thymoma, older mice had well-differentiated thymic carcinoma (WDTC) or poorly differentiated thymic carcinoma. When SV40T TG mice (248 line) reached a certain age, carcinoma of the thymus was present in all of them. Cortical-type thymoma became malignant within a predictable time span, suggesting a cortical thymoma-carcinoma sequence. When the mice were 9 weeks of age, the thymuses formed gross masses compatible with cortical thymoma. At 14 weeks of age, WDTC appeared against the background of cortical thymoma. Poorly differentiated thymic carcinoma was found after 15 weeks and affected all animals over 23 weeks of age. Most thymic carcinomas coexisted in varying proportions with cortical-type thymoma. Medullary thymomas did not develop in the mice, and no transition from medullary-type thymomas to thymic carcinomas was observed. In this SV40T transgenic mouse model, thymic carcinoma is clearly preceded by cortical-type thymoma. These transgenic mice may provide an interesting model for the progression from cortical thymoma to WDTC and/or high-grade carcinoma.

Aging↗
PubMed1998

Expression of heat shock protein 70 blocks thymic differentiation of T cells in transgenic mice.

Heat shock protein 70 (HSP70) is involved not only in protein folding, but also in processes of differentiation and cell-cycle progression. Recently, HSP70 has been implicated in mediation of functions of some immunosuppressive agents. To study the role of HSP70 in differentiation of haematopoietic cells, we generated transgenic mice using the human inducible hsp70 gene fused to the mouse H-2K promoter. These mice develop a T-cell deficiency that is characterized by thymic hypoplasia and a significant reduction in peripheral T cells. The total number of thymocytes is about 100-fold less than that in normal mice. The majority of the thymocytes are immature T cells that express neither CD4 nor CD8 molecules, indicating that T cells are affected at an early stage of thymic differentiation. Expression of the transgenic HSP70 was detected both in bone marrow cells and in thymocytes. Furthermore, injection of normal bone marrow cells into the T-cell deficient mice led to the generation of mature T cells indicating that the T-cell deficiency was caused by the action of HSP70 in T cells. The blockage of differentiation occurred only in T cells, both alphabeta- and gammadelta-T-cell receptor (TCR)-bearing cells, but not in B cells, granulocytes, and monocytes. The observations suggest that HSP70 may inhibit a cellular process that is essential for the differentiation of early stage T cells. Further experiments using this model system will widen our understanding of HSP70 and its function on a molecular level.

Animals↗
PubMed1998

Rocuronium versus succinylcholine: are they equally effective during rapid-sequence induction of anesthesia?

UNLABELLED: The purpose of our study was to assess the onset and quality of muscle paralysis and intubation conditions with succinylcholine (Sch) or rocuronium (Roc) during rapid-sequence induction. Patients were randomly assigned to receive thiopental (5 mg/kg) and Sch (1.5 mg/kg) or thiopental (5 mg/kg) and Roc (1.2 mg/kg). The anesthesiologists performing the endotracheal intubation were blinded by standing with their back to the patient. Thirty seconds after drug administration, laryngoscopy was performed. Intubating conditions were scored, the clinical onset of apnea was noted, and a train-of-four monitor recorded data. All patients were ASA physical status I-III and scheduled for emergency procedures; both groups were demographically similar. Thirteen patients received Roc and 13 received Sch. There was no significant difference between the two groups in the number of patients receiving excellent intubating scores (P = 0.41) or in the combined number of patients receiving good and excellent scores (P = 1.0). There was no significant difference in time of onset of apnea for Sch (22+/-13 s) versus Roc (16+/-8s). The return of the first twitch response was significantly faster with Sch (5.05+/-2.5 min) compared with Roc (17.3+/-21.7 min) (P = 0.0001). IMPLICATIONS: In pediatric patients scheduled for emergency surgery, thiopental 5 mg/kg and rocuronium 1.2 mg/kg provided conditions for the completion of intubation in <60 s comparable to those provided by thiopental 5 mg/kg and succinylcholine 1.5 mg/kg. We conclude that rocuronium is a reasonable substitute for succinylcholine in children for rapid-sequence intubation when a rapid return to spontaneous respiration is not desired.

Adolescent↗
PubMed1997

Binding of chimeric analogs of omega-conotoxin MVIIA and MVIIC to the N- and P/Q-type calcium channels.

Despite their high sequence homology, the peptide neurotoxins omega-conotoxin MVIIA and MVIIC selectively block N- and P/Q-type calcium channels, respectively. To study the recognition mechanism of calcium channel subtypes, two chimeric analogs of omega-conotoxin MVIIA and MVIIC were synthesized by exchanging their N- and C-terminal halves. Binding assay for both N- and P/Q-type calcium channels showed that amino acid residues restricted to the N-terminal half are important for the recognition of N-type channels, whereas essential residues for P/Q-type channel recognition are widely spread over the whole omega-conotoxin molecule.

Amino Acid Sequence↗
PubMed1997

Circular dichroism spectra of calcium channel antagonist omega-conotoxins.

The circular dichroism (CD) spectrum of omega-conotoxin GVIA is quite different from those of omega-conotoxin MVIIA and MVIIC, despite their distinct similarity in three dimensional structures. In order to characterize the unique CD spectrum of omega-conotoxin GVIA, we focused our attention on the aromatic chromophore and analyzed the CD spectra of three synthetic analogs, in which Tyr13, Tyr22, and Tyr27 were individually replaced by alanine. Replacement of Tyr27 caused a significant change in both the near- and far-ultraviolet CD spectrum of omega-conotoxin GVIA and resulted in the omega-conotoxin MVIIA/MVIIC-like pattern, suggesting that Tyr27 has a dominant contribution to the unique CD profile of omega-conotoxin GVIA.

Alanine↗
PubMed1997

The great Hanshin-Awaji earthquake aggravates blood pressure control in treated hypertensive patients.

A major earthquake (Hanshin-Awaji earthquake) struck Kobe on January 17, 1995. We had a unique opportunity to study the effect of tremendous psychological stress on blood pressure control in 221 hypertensive patients receiving antihypertensive medication. During the 4 weeks after earthquake, on average, the mean blood pressure increased significantly for both 105 patients who were exposed (living in the area of the very severe earthquake) and 116 patients who were not exposed (living in the surrounding area) (+4.2 +/- 1.0 mm Hg, P < .001, and +/- 2.4 +/- 0.7 mm Hg, P < .005, respectively). In the exposed group, the increase in mean blood pressure peaked in the first week (+6.7 +/- 1.6 mm Hg, P < .001), declined thereafter, and returned to the baseline within 6 weeks after the disaster. The earthquake related blood pressure elevation was, however, significantly attenuated (P < .02) in patients receiving beta-blockers compared with those receiving other drugs. The results indicate that acute psychological stress associated with a sudden natural disaster causes blood pressure elevation in treated hypertensive patients, and suggest the beneficial effect of beta-blockers on such a stress-associated high blood pressure.

Analysis of Variance↗
PubMed1997

Management of urinary calculi in pregnant women.

The incidence and predisposing factors of urinary calculi are generally the same in both pregnant and non pregnant women, but anatomic changes during pregnancy make diagnosis and treatment a more challenging issue. We reviewed 16 patients (22 stones) of urinary stone during pregnancy between 1986 and 1996 at Kyung Hee Medical Center. The most common symptom was flank pain, seen in 81.3% of patients, while 68.8% of patients were displayed microscopic hematuria. In all cases, diagnosis was made by abdominal ultrasound, there was no need for other harmful investigate procedures. Forty point nine percent of the total stones (9/22) were passed spontaneously, double J stenting was carried out in three cases because of persistent pain or urinary tract infection (UTI), ureteroscopic stone removal was performed in one case. Based on our experience and a review of the literature, abdominal ultrasound should be performed first and in all cases appears sufficient for the diagnosis of a stone. In case of persistent pain or urinary tract infection, a double J stent is more effective than percutaneous nephrostomy.

Adult↗
PubMed1996

Development of thymic carcinoma in transgenic mice expressing SV40 T antigen.

We produced transgenic mice using SV40 Tag gene under the control of its own enhancer and promoter. Three transgenic lines (SNU-SVT125, 127, 248) consistently developed thymic carcinoma as well as choroid plexus carcinoma and dysplastic renal tubule. In SNU-SVT248 line, SV40 Tag transgene was expressed at thymus, spleen and kidney. Thymic epithelium showed high level expression of SV40 Tag in immunohistochemistry. Histopathological and electron microscopic analysis revealed that poorly differentiated carcinoma was derived from type 2 to 4 thymic epithelial cell. Our transgenic mice would provide a model for studies on the pathogenesis of thymic carcinoma and on the regulation of thymopoiesis by epithelial cells.

Animals↗
PubMed1996

T cell lymphoma in transgenic mice expressing the human Hsp70 gene.

In the course of studying the role of hsp70 in the differentiation of pancreatic beta cells, transgenic founder mice were generated with the human hsp70 gene fused to the human insulin gene promoter. One resulted in a transgenic line that consistently developed diabetes mellitus, but unexpectedly three other independent transgenic founders developed generalized malignant lymphoma within 10 months after birth. Immunochemical and RT-PCR analyses revealed that the transgene was expressed in the lymphoma cells. Flow cytometric analyses revealed that the tumor was originated from T lymphocytes. Our results provide the first experimental evidence that hsp70 is involved in the tumorigenesis of T cells most likely through the blockage of apoptotic signals.

Animals↗
PubMed1996

Laser induced breakdown spectroscopy (LIBS) as an analytical tool for the detection of metal ions in aqueous solutions.

Laser induced breakdown spectroscopy (LIBS) is applied to analyze aqueous solutions of Li(+), Na(+), Ca(2+), Ba(2+), Pb(2+), Cd(2+), Hg(2+) and Er(3+) and suspensions of ErBa(2)Cu(3)O(x) particles (d=0.2 microm). An excimer (308 nm) pumped dye laser with laser pulse at 500 nm and pulse energy at 22+/-2 mJ is used to produce plasma in aqueous solution. Plasma emission lines of the elements are detected by a photodiode array detector. Detection limits of the metal ions are 500 mg/l for Cd(2+), 12.5 mg/l for Pb(2+), 6.8 mg/l for Ba(2+), 0.13 mg/l for Ca(2+), 13 microg/l for Li(+) and 7.5 microg/l for Na(+). No mercury and erbium emission can be detected, even at Hg(2+) and Er(3+) concentrations of up to the g/l range. On the other side, for Er in suspensions of ErBa(2)Cu(3)O(x) particles a more than 10(3) times higher sensitivity is found than for dissolved Er(3+). This result gives a possibility to analyze colloid-borne metal ions with an increased sensitivity.

Journal Article↗
PubMed1996

Effect of rifampin on the plasma concentration and the clinical effect of haloperidol concomitantly administered to schizophrenic patients.

We assessed the changes of plasma haloperidol concentrations and clinical responses repeatedly up to 4 weeks after coadministration or discontinuation of rifampin in 12 schizophrenic patients taking haloperidol alone (group I) and 5 patients taking haloperidol and antituberculotic drugs (group II). After coadministration of rifampin in group I, daily trough haloperidol concentrations rapidly decreased and reached 63% of baseline level by day 3, 41.3% by day 7, and 30% by day 28. On the other hand, after discontinuation of rifampin in group II, plasma haloperidol concentration increased to 140.7% of baseline level by day 3, 228.7% by day 7, and 329% by day 28. In this study, a 30% or greater change in the clinical rating scale was considered a positive clinical response of the drug interaction. Using this criterion, 50% of the group I subjects responded according to the Brief Psychiatric Rating Scale (BPRS) total score, and 25% responded according to the BPRS subscale for psychiatric symptoms. No positive responses were observed in group II patients. These results strongly suggest that rifampin interacts with the clinical effects as well as the plasma concentrations of coadministered haloperidol, and careful monitoring should be considered when coadministration or discontinuation of rifampin is needed in a schizophrenic patient taking haloperidol.

Adult↗
PubMed1995

Cloning of a novel crystal protein gene cry1K from Bacillus thuringiensis subsp. morrisoni.

A novel crystal protein gene cry1K has been cloned and sequenced from a Bacillus thuringiensis subsp. morrisoni BF190 isolated from phylloplane. The upstream promoter region of cry1K was almost identical with that of cry1B. The deduced amino acid sequence of Cry1K contains 1215 amino acid residues with an estimated molecular mass of 137 kDa. Comparison of the amino acid sequence of the Cry1K with that of Cry proteins revealed that Cry1K is most closely related to Cry1B and Cry1I. Cry1K has a high degree of identity with Cry1B in the region between initiator codon and conserved sequence block 1, and with Cry1F in the region between conserved block 3 and 5. Protein inclusion purified from a recombinant strain of B. thuringiensis expressing the cry1K gene was found to have a different insect-host specificity from Cry1B, Cry1I and Cry1F, Cry1K was found to be selectively toxic to Artogeia rapae and not active to Plutella xylostella.

Amino Acid Sequence↗
PubMed1995

Tyr13 is essential for the binding of omega-conotoxin MVIIC to the P/Q-type calcium channel.

An analog of omega-conotoxin MVIIC (Y13A-MVIIC) was synthesized by replacing Tyr13 with Ala to study the role of Tyr13 residue conserved in many omega-conotoxins. Y13A-MVIIC has an overall conformation similar to that of the native toxin, but an enormously reduced ability to displace 125I-omega-conotoxin MVIIC binding to rat cerebellar P2 membranes. These results suggest that Tyr13 is essential for the activity of omega-conotoxins at P/Q-type calcium channels.

Amino Acid Sequence↗