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Biomedical subjects

J W Kim

Publications and source records attributed to J W Kim.

At least 19 recordsLinked to original sources
PubMed1995

Cloning and characterization of rat pancreatic beta-cell/liver type glucose transporter gene: a unique exon/intron organization.

Four overlapping lambda genomic clones encoding rat pancreatic beta-cell/liver type glucose transporter (GLUT2) have been isolated and characterized. The gene is about 35 kb long and contains 14 exons and 13 introns. Contrary to the exon 1 of the human or mouse counterpart, the rat GLUT2 gene has three additional noncoding exons which were identified by 5'-RACE and all four were designated exon 1a, 1b, 1c, and 1d. The intron sequences bordering the splice site junctions generally follow the GT/AG rule except for one intron which begins with GC. The exon sequences determined from genomic DNA sequencing showed some differences when compared to the published rat GLUT2 cDNA. Transcription initiation site was determined by primer extension and located 661 bp upstream of the ATG translation initiation codon. Several potential binding sites for transcription factors such as C/EBP, Sp1, AP1, HNF-5, and UPE were observed and they may be responsible for the regulation of GLUT2 gene expression. The promoter region of rat GLUT2 showed little homology when compared with those of human or mouse. However, striking sequence identity (84%) was found when the adjacent intron regions flanking exon 1c were compared with the -970/-721 region of the mouse GLUT2 promoter. A series of deleted mutant constructs of the putative promoter region linked to the CAT reporter gene showed promoter activity in the primary hepatocyte culture. The region containing -4542/+240 showed the highest CAT activity and further deletion of the region showed gradual decrease in CAT activity.

Alternative Splicing↗
PubMed1995

Establishment and characterization of a cell line (CUMC-3) derived from a human squamous carcinoma of the uterine cervix.

A new cell line, CUMC-3, has been derived from an invasive nonkeratinizing squamous cell carcinoma of the uterine cervix in a 32-year-old patient. It has been maintained in long-term culture for 59 months, and passaged over 310 times. Monolayer-cultured cells were polygonal in shape, showing a pavement-like arrangement and a tendency to pile up without contact inhibition. The epithelial nature of the cultured CUMC-3 cells was also confirmed by transmission electron microscopy which demonstrated the presence of desmosomes and tonofilaments. The cells were highly tumorigenic in nude mice and the transplanted tumors were poorly differentiated squamous carcinoma which closely resembled the original tumor. Cultured cells obtained from the CUMC-3-derived nude mouse tumor, CUMC-3N, also were studied for its characterization. Repeated chromosome analysis revealed a stable clone with the modal chromosome number of 78. The metaphase of this cell line had multiple structural aberrations of chromosomes 1, 3, 8, 10, 11, 20, and X and showed several markers of unknown origin. The results of isozyme analyses were distinct from the HeLa cell line. The identical genetic signature was demonstrated both in CUMC-3 and in CUMC-3N cells. Cultured CUMC-3 cells produced human chorionic gonadotropin beta-subunit and tumor antigen of squamous cell carcinoma (TA-4). Cytosol estrogen receptors were found in this cell line but progesterone receptors were not measured. HLA typing of CUMC-3 cells indicated the presence of DR4, DR8, DQw3, and DQw6. The result of oncogene analysis using Southern blotting technique revealed no amplification of oncogene c-myc. Analysis of the DNA samples extracted from the CUMC-3 cells showed the presence of human papillomavirus type 16 DNA. Using the single-strand conformation polymorphism technique, we have screened CUMC-3 cells for p53 mutation in exons 4 to 9. No mobility shift was observed in this cell line. This cell line may be useful in studying the in vitro and in vivo properties of human cervical carcinoma.

Adult↗
PubMed1995

Aberrations of the p53 tumor suppressor gene in human epithelial ovarian carcinoma.

Aberrations of the p53 gene in 26 surgical specimens of human epithelial ovarian carcinomas were examined by single-strand conformation polymorphism (SSCP) analysis of polymerase chain reaction (PCR) products. Seven (27%) of the tumors demonstrated a SSCP band shift in exons 4 to 9 of the gene, including 5 in the region encompassing exons 5 and 6, 1 in exon 7, and 1 in the region encompassing exons 8 and 9. Mutations were clustered in exon 5 in highly conserved regions of the p53 gene. All of the abnormal DNA fragments have been further characterized by direct DNA sequencing. These include five missense mutations (five transitions), a one-base-pair deletion introducing, by frameshift, a stop codon further downstream, and a two-base-pair insertion introducing a stop codon downstream by frameshift. Most mutations were base substitutions, and were clustered in exon 5 (71%), especially codons 175 and 179. The aberrations of the p53 gene were only found in tumors of FIGO stages III and IV. Histologic grading was also reviewed with respect to p53 aberrations. The aberrations were absent in well-differentiated carcinomas. The more undifferentiated the primary tumor, the more frequent p53 mutation (P < 0.05). Our results indicated that the aberrations of the p53 gene were common in epithelial ovarian cancers and p53 aberration may occur late during ovarian cancer evolution.

Base Sequence↗
PubMed1995

Comparative study of the patients with locally advanced stages I and II cervical cancer treated by radical surgery with and without preoperative adjuvant chemotherapy.

Ninety-two patients with locally advanced stages IB, IIA, and IIB cervical cancers, who had completed 4 years of follow-up after treatment with preoperative adjuvant chemotherapy prior to radical surgery, were compared with 138 patients in same disease status who were treated with radical surgery without preoperative adjuvant chemotherapy. In the patients treated with preoperative adjuvant chemotherapy (VBP scheme), the chemotherapeutic response was more favorable in squamous cell carcinomas (87%) than that in adenocarcinomas (38%). The detection rate of pelvic lymph node metastasis from the surgical specimens of radical operation was higher in the patients of radical surgery without preoperative chemotherapy (34%; 47/138) than that in the preoperative adjuvant chemotherapeutic patients (17%; 16/92, P = 0.005). Recurrence occurred in 50 of 138 patients (35.5%) who were treated by radical surgery without preoperative chemotherapy and in 17 of 92 patients (18.5%) who were treated with preoperative adjuvant chemotherapy followed by radical surgery. The difference of recurrence rate between two groups was statistically significant (P = 0.004). The tumor-free survival of preoperative adjuvant chemotherapeutic patients was significantly longer than those in the patients without preoperative chemotherapy (P = 0.0067). Tumor response to chemotherapy was a valuable prognostic factor in management of patients and preoperative adjuvant chemotherapy was beneficial in reducing pelvic lymph node metastases, reducing recurrences, and prolonging the survival of the patients with locally advanced cervical cancers, especially in stage IIA.

Adult↗
PubMed1995

Mandibular reconstruction with free vascularized fibular flap.

Although various sources of vascularized bone/composite tissue have been used for mandibular reconstruction, the vascularized fibular flap has been reported to have many advantages over the others and to be the most suitable for bridging a long-span mandibular defect. In this paper, positive experience of 14 consecutive cases in which a free vascularized fibular graft with or without a skin paddle has been used to reconstruct a long mandibular defect is reported. Half of the cases were primarily reconstructed, the rest secondarily. The average length of the fibula graft harvested was 16.7 cm, with a range of 12 to 22 cm. The number of wedge osteotomies ranged from 0 to 4, with an average of 1.67. In ten flaps, a peroneal skin paddle was included. The donor wound was typically closed directly, except in three cases, where a skin graft was used. Vein grafts were performed in five cases to lengthen the pedicle. In two cases, the skin partially necrosed. All scintigrams except one showed good bone viability. But there was no total flap failure. Postoperative facial appearances were fair to excellent, with mouth opening ranging from 21 to 50 mm. Although unusual serious donor wound rupture was experienced in one case, in general the donor site complications were minimal.

Adult↗
PubMed1995

The nucleotide sequence of cowpea mottle virus and its assignment to the genus Carmovirus.

The genome of cowpea mottle virus (CPMoV) is a positive ssRNA of 4029 nucleotides with six major open reading frames (ORFs). A non-coding region of 34 nucleotides precedes the first AUG. ORF1 encodes a 25 kDa polypeptide of unknown function and ORF2 encodes a 56 kDa putative RNA replicase. Like other members of carmoviruses, suppression of the amber termination codon of ORF1 would produce a readthrough polypeptide of 83 kDa. ORF3 and ORF4 encode two small proteins of 7.8 and 9.8 kDa, respectively. ORF5 encodes the 40 kDa capsid protein. ORF6 is located within ORF5 but is in a different frame and has no postulated function. CPMoV RNA is blocked at the 5' end and is not polyadenylated at the 3' end. Comparison of the physicochemical properties, genomic arrangement, and predicted amino acid sequences with those of other viruses justify the assignment of CPMoV to the genus Carmovirus, family Tombusviridae.

Amino Acid Sequence↗
PubMed1995

Characteristics of acromegalic patients with a good response to octreotide, a somatostatin analogue.

BACKGROUND AND OBJECTIVES: In GH-secreting pituitary tumours somatostatin receptor density has been correlated with octreotide responsiveness. Little is known about the other endocrine characteristics of patients with good responses to octreotide. The purpose of this study was to determine the characteristics of these patients. PATIENTS: We studied 30 patients with active acromegaly. Five had been treated with either transsphenoidal adenomectomy or conventional radiotherapy without cure of GH excess. DESIGN: Patients were divided into good or poor octreotide responders. Patients whose GH level decreased to less than 20% of basal and below 20 mU/I after a subcutaneous injection of 100 micrograms of octreotide were defined as good octreotide responders. We compared tumour size, basal GH secretory pattern, responses to TRH, GnRH and bromocriptine, and mutation of the alpha-subunit of stimulatory GTP-binding protein (G alpha s) between the two groups. MEASUREMENT: Tumour size was determined by CT or MRI. Basal GH level was measured hourly between 0800 and 1600 h. GH responses to TRH and GnRH were measured every 30 minutes for 2 hours, and the GH response to oral bromocriptine was measured hourly for 6 hours. The mutation of G alpha s gene between codons 184 and 251 was examined by direct sequencing using PCR in 5 patients of each group whose tumour tissues were available for the genomic DNA extraction. RESULTS: Seventeen patients (57%) were good octreotide responders (group I) and 13 (43%) were poor responders (group II). The mean age, sex, tumour size, tumour grade and the basal GH secretory pattern were not significant different between the two groups. Group I responded more frequently than group II to TRH (65 vs 25%). Fifty-three per cent of group I patients and none of group II were good bromocriptine responders. Forty-one per cent of group I patients responded to both TRH and bromocriptine. Three of 5 group I tumours had point mutations at codon 201 of the G alpha s gene, none of 5 group II tumours had mutations. CGT(Arg) was replaced with TGT(Cys) in two tumours and with AGT(Ser) in one. No mutations were found at codon 227. All three tumours with mutations were from patients responsive to TRH. Two of the three were also good bromocriptine responders. CONCLUSIONS: These data suggest that good octreotide responders are more likely to respond to TRH or bromocriptine. Good octreotide responders may include subgroups with different levels of TRH and dopamine receptor expression. A possible relation between octreotide response and the mutation of G alpha s gene should be investigated.

Acromegaly↗
PubMed1994

Limbic system fos expression associated with paternal behavior.

Axon-sparing lesions of the medial nucleus of the amygdala (MeA) decrease male parental behavior in the highly social prairie vole. To assess further the role of the amygdala in paternal behavior, male and female prairie voles were exposed to a pup or a non-social olfactory stimulus for 3 hours, and cells expressing Fos peptide were labelled using immunocytochemistry. Compared to controls, males exposed to a pup showed an increase in Fos expression in the MeA, as well as in several areas with connections to it: the accessory olfactory bulb, lateral septum, medial preoptic area, medial bed nucleus of the stria terminalis, nucleus reuniens and paraventricular nucleus of the thalamus. There was no increase in Fos immunoreactivity in the paraventricular nucleus of the hypothalamus or piriform cortex. The same pattern of Fos expression was found in female voles, with the exception of the thalamic paraventricular nucleus, where there was an increase in the pup-exposed group that was not statistically significant (P = 0.11). In addition, the magnitude of induction in females was markedly less than that in males in the medial preoptic area. These results provide further evidence that the MeA is involved in paternal behavior, and suggest certain other areas previously implicated in meternal behavior may also be involved in the control of paternal behavior in this species.

Animals↗
PubMed1994

The FeSII protein of Azotobacter vinelandii is not essential for aerobic nitrogen fixation, but confers significant protection to oxygen-mediated inactivation of nitrogenase in vitro and in vivo.

The FeSII protein of Azotobacter vinelandii has been proposed to mediate the 'conformational protection' of the molybdenum-dependent nitrogenase components against oxygen inactivation. We have cloned and characterized the structural gene for the FeSII protein (the fesII locus). Hybridization studies did not reveal the presence of fesII-like genes in a number of diverse species of well-studied nitrogen-fixing bacteria, with the exception of Azotobacter chroococcum. The fesII locus is transcriptionally expressed during both nitrogen fixing and non-nitrogen fixing conditions, although the level of its message is upregulated by approximately 2.5-fold during nitrogen fixation. The promoter region was identified by primer extension analysis, and is similar to other sigma 70-type promoters. Mutants devoid of the FeSII protein were constructed. These mutants possessed growth characteristics on a variety of carbon substrates during non-diazotrophic as well as diazotrophic growth that were essentially indistinguishable from the wild-type strain. Nevertheless, the nitrogenase activity in cell-free extracts is significantly more sensitive to irreversible oxygen inactivation in the mutants as compared with the wild type. When treated with 250 mM NaCl (a condition known to dissociate FeSII from nitrogenase components), the wild-type and mutant extracts were equally hypersensitive to oxygen inactivation. Upon energy starvation, conditions in which 'respiratory protection' is inoperable, the MoFe and Fe proteins of nitrogenase are degraded much more rapidly in vivo in the deletion mutants, compared to the wild type. Strains relying on either the vanadium or the 'iron-only' alternative nitrogenases exhibited similar growth rates irrespective of the presence or absence of the FeSII protein, and the in vitro inactivation of the vanadium nitrogenase components was not affected by the lack of the FeSII protein. All in all, these results are consistent with a model whereby 'respiratory protection' is the major physiological mechanism responsible for the protection of all three nitrogenases during energy-supplemented growth. Upon energy starvation, however, 'conformational protection', mediated by the FeSII protein is capable of temporarily protecting the conventional molybdenum nitrogenase components from inactivation and subsequent degradation.

Aerobiosis↗
PubMed1994

Bilateral primary pigmented nodular adrenocortical disease--a case of report describing a rare cause of Cushing's syndrome.

A case of Cushing's syndrome due to bilateral pigmented nodular adrenal disease in a 35-year-old male is presented. The adrenals showed multiple, black, variable sized nodules. Histologically the cells contained lipofuscin and either had a clear cytoplasm or an eosinophilic cytoplasm with a prominent nucleus. Lymphocytic infiltration and fatty metaplasia within the nodules are two of the prominent histological features. There is extreme internodular atrophy which suggests that primary pigmented nodular adrenocortical disease is a non-adrenocorticotropic hormone dependent condition. Since the disorder appears to involve primarily the cortex of both adrenals, the treatment of choice is bilateral adrenalectomy followed by steroid replacement. The characteristic clinicopathological manifestations that separate this diagnosis from other types of adrenal disease are also discussed. This is the first reported case in Korea to be documented with the pertinent clinicopathological findings.

Adipose Tissue↗
PubMed1994

The utilization of Doppler ultrasonography with color flow mapping in the diagnosis and evaluation of malignant trophoblastic tumors.

The Doppler ultrasound with color flow mapping image has been recently applied for the evaluation of gynecologic diseases, in particular, malignant trophoblastic tumors with the characteristic abundant blood flow. Doppler color flow mapping of uterine artery and intratumoral blood vessels was performed at a regular interval in all 26 patients including 3 cases of lost for follow up. Systolic/diastolic (S/D) ratio representing blood flow was measured in 19 cases of malignant trophoblastic tumors and 7 cases of hydatidiform mole diagnosed at the department of Obstetrics and Gynecology, Yonsei University, College of Medicine. The initial mean S/D ratio and standard deviation(SD) of uterine artery in 11 remitted and 5 non-remitted patients were 2.72 +/- 1.31 and 2.69 +/- 1.80, respectively. No significant difference was noted between two groups. However, the final S/D ratio of uterine artery in remitted group showed significantly higher values than non-remitted group, of which values were 6.23 +/- 2.38 and 3.08 +/- 1.54, respectively (P < 0.05). In aspect of blood flow changes in malignant trophoblastic tumors after chemotherapy, remitted group showed entirely disappeared blood flow, while non-remitted group had persistent blood flow. The mean S/D ratio and SD measured in hydatidiform mole patients were 5.43 +/- 1.65, of which value reflects higher resistance than malignant trophoblastic tumors. Also blood flow was not detected in all cases. This study suggests that color flow mapping Doppler ultrasound can be a useful method in diagnosing and monitoring the treatment in malignant trophoblastic tumors along with the conventional serum beta-hCG titration.

Adult↗
PubMed1994

Polymorphism of glucokinase gene in non-insulin dependent diabetes mellitus.

Several lines of evidence suggest a strong genetic component to NIDDM. To clarify the role of glucokinase gene in the development of NIDDM, restriction fragment length polymorphism (RFLP) of glucokinase gene and 3' microsatellite polymorphism analyses by polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) were performed in NIDDM and control subjects. Compared to NIDDM with 1.3 kb allele/Pvu I digestion of glucokinase, 10% of NIDDM did not demonstrate 1.3 kb allele and these patients were characterized by increased insulin secretion. In 3' microsatellite polymorphism analysis, autoradiography of PCR products revealed three different alleles, including Z, Z + 2 and Z + 4. Z was the most common allele in both NIDDM and nondiabetic controls. There was no significant allele associated with NIDDM. Frequency of the homozygote Z/Z genotype was significantly lower in NIDDM subjects (16.7%) compared to normal control (46.7%)(p < 0.05). There was no difference in clinical findings according to 3' microsatellite genotypes in NIDDM. These data suggest that there does not appear to be a significant glucokinase allele associated with NIDDM but Z/Z genotype may play a suppressive role in the pathogenesis of a certain type of NIDDM in Korea. Further studies may be required to identify the molecular basis of this association.

Base Sequence↗
PubMed1994

Clozapine therapy in refractory affective disorders: polarity predicts response in long-term follow-up.

BACKGROUND: To determine the efficacy and tolerance of long-term clozapine therapy in refractory affective illness. METHOD: Hospital records were reviewed for 193 treatment-resistant patients with a discharge diagnosis of bipolar disorder (N = 52), schizoaffective disorder (N = 81), unipolar depression (N = 14), schizophrenia (N = 40), or other disorders (N = 6) started on clozapine therapy as inpatients at McLean Hospital. An independent "best-estimate" diagnosis, based on DSM-III-R criteria, was established for each patient. Patients were contacted at least 6 months after clozapine initiation for structured follow-up interviews by raters blind to diagnosis. Patients were stratified by diagnosis, and a variety of patient characteristics and outcome measures were compared. RESULTS: Subjects were followed up a mean of 18.7 months after clozapine initiation. Bipolar manic and schizoaffective bipolar subjects had significantly better outcomes than unipolar, bipolar, and schizoaffective depressed patients on a variety of measures. One or more episodes of depression prior to clozapine predicted clozapine discontinuation (p = .01). Affective and schizoaffective subjects had baseline measures of social functioning similar to that of the schizophrenics but had significantly greater improvement in scores at follow-up. CONCLUSION: Clozapine is an efficacious and well-tolerated therapy for refractory affective illness. Manic symptomatology predicts a more favorable response than depression.

Adult↗
PubMed1993

Production and characterization of monoclonal antibody that simultaneously recognizes methamphetamine and its major metabolite.

A series of monoclonal antibodies (mAbs) that react with methamphetamine-bovine serum albumin (MA-BSA) were established by intrasplenic immunization method. Among established 36 clones, two typical mAbs, designated NK-1 and NK-2, were described. The inhibition assay of enzyme-linked immunosorbent assay (ELISA) analysis using methamphetamine analogs indicated that NK-1 showed considerable reactivity not only MA-BSA but also methamphetamine and its major metabolite, para-hydroxymethamphetamine (p-hydroxymethamphetamine). The cross-reactivity between NK-1 and the methamphetamine analogs with modified alkyl side chain, indicates that methyl groups of R5 and R7 in the methamphetamine molecules are important for the maximum affinity. The length of alkyl side chain on methamphetamine significantly affected the binding affinity of NK-1. The results may suggest that NK-1 will recognize not only methamphetamine but also the bridge part of the methamphetamine that binds the methamphetamine molecules to a carrier protein.

Animals↗
PubMed1992

Effect of genetic background on the developmental expression of c-fos and c-myc in chicken.

The developmental expression of the protooncogenes, c-fos and c-myc, in muscle and liver of 14- and 19-day embryos and 1-, 6-, 8- and 28-day-old chicks of Athens Canadian Random Bred (ACRB) Single Comb White Leghorn (SCWL) and Peterson X Arbor Acres commercial broiler (PXAA) was determined. For the three stocks of chicken, significant differences were found in c-fos and c-myc expression. For both muscle and liver, averaged across ages, abundance of c-fos RNA was highest in PXAA and lowest in ACRB with differences significant at the P less than 0.01 level. c-myc RNA levels were significantly higher (P less than 0.01) in PXAA than in ACRB or SCWL liver. Taken over the developmental period, expression of c-fos RNA in muscle increased at different rates between breeds from 14-day embryo levels to peak levels in 6- to 8-day-old chicks and declined in 28-day-old chicks. Levels of c-fos were much lower in liver and showed no consistent differences related to developmental stage. A steady decline in c-myc from 14-day embryo levels to 28-day-old chicks was found in both muscle and liver. This decline in c-myc levels generally parallels the decline in relative growth rates which occurs in all breeds over the developmental period. In liver, the fast growing PXAA had the highest levels of c-myc, c-fos, on the other hand, showed elevated levels in PXAA for both muscle and liver and distinctly different patterns between these two tissues over the developmental period, suggesting tissue-specific involvement in growth.

Animals↗
PubMed1992

Estrogen and progesterone receptor assay in carcinoma of the cervix with monoclonal antibodies.

The normal cervix has been shown to contain estrogen and progesterone receptors (ER and PR), but there have been controversial reports on the presence of these receptors in cervical carcinoma. Thus to explore the relationships between the steroid receptor status and cervical carcinoma, tissues of 34 patients with invasive cervical carcinoma prior to treatment and 30 cases of control who underwent hysterectomy due to benign gynecologic diseases at Yonsei Medical Center were analyzed for ER and PR using immunocytochemical assay with monoclonal antibodies and the results were compared with those of conventional steroid binding assay. ER and PR were positive in 65 and 71% of all tumors, respectively, and 59% of the cases were positive for both receptors simultaneously. No significant difference in receptor levels was noted when stratified according to menopausal status or clinical stage. With regard to tumor size, lesions greater than 3 cm had significantly lower receptor positivity when compared with the control. For the histological cell types, a statistically significant higher mean ER level was noted in adenocarcinoma compared to squamous cells. Even though the potential therapeutic significance of these findings is not yet known, they are consistent with the concept that steroid receptors can be used as a guide to endocrine therapy with respect to other prognostic parameters. However, the small number of advanced-stage carcinomas and the absence of data regarding survival rate in this study preclude any definite conclusions.

Adult↗
PubMed1992

Mapping and sequence analysis of the capsid protein gene of cowpea mottle virus.

Twelve cDNA clones were generated, covering approximately 95% of the cowpea mottle virus (CMeV) genome from the 3' end to near the 5' end. The entire capsid protein sequence of 1,104 nucleotides was contained in two clones located near the 3' terminus. The codons represented 367 amino acids (M(r) 39,611). The postulated amino acid sequence of CMeV capsid protein had 36% homology to turnip crinkle virus and 26% homology to carnation mottle virus in the arm and S domains, but western blots showed no serological relationship to either. On the basis of the organization and expression of its genome and its physicochemical properties, CMeV is assigned to the carmovirus group. Like other carmoviruses, CMeV generates three dsRNAs which are co-terminal at the 3' end in infected tissues, but CMeV differs from other carmoviruses in the absence of encapsidated subgenomic RNAs.

Amino Acid Sequence↗