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Biomedical subjects

K Kim

Publications and source records attributed to K Kim.

At least 505 records · Page 28Linked to original sources
PubMed1990

Prospective study of early detection of hepatocellular carcinoma in patients with cirrhosis.

We prospectively monitored 140 cirrhotic patients for the development of hepatocellular carcinoma for 6 yr, using periodical screening by high-resolution convex-array ultrasonography and alpha-fetoprotein. Twenty-eight patients were positive for HBs antigen, 26 patients had received blood transfusions and were negative for HBs antigen and 26 patients had a history of heavy drinking. We detected hepatocellular carcinoma in 40 patients during this period. The overall cumulative incidence of hepatocellular carcinoma in the 6 yr was 39%; the cumulative incidence was 59% in patients with HBsAg, 53% in patients who had had blood transfusions and were negative for HBsAg and 22% in patients who had a history of heavy drinking and who were without HBsAg. Detection of the carcinoma in 85% of these 40 patients was based on results of ultrasonography. Twenty-six of the patients (65%) had a small hepatocellular carcinoma of 2 cm or less. alpha-Fetoprotein levels were lower than 100 ng/ml in 56% of these 40 patients. Patients with cirrhosis are at high risk of developing hepatocellular carcinoma, especially patients with HBsAg or with a history of blood transfusion who are negative for HBsAg. Periodic monitoring by use of ultrasonography in particular is recommended for early detection of hepatocellular carcinoma.

Adult↗
PubMed1990

Regulation of laminin gene expression in the expansion of mouse blastocysts.

This study aims to elucidate gene expression of laminin and its role in expansion of the blastocyst during mouse early embryo-genesis. The gene expression of laminin, in particular the B1 subunit and the synthesis of laminin polypeptides, was examined during the expansion of blastocyst by a RNA-blot hybridization with 32P-labeled laminin B1 cDNA and immunoprecipitation followed by a SDS-PAGE, respectively. Laminin B1 transcript was actively expressed in the blastocyst stage of embryos. The gene expression of laminin B1 and the synthesis of laminin protein were also increased when blastocyst was expanded. Treatments of cAMP analogue, isobutylmethylxanthine, forskolin, and cholera toxin, which are known to stimulate the blastocyst expansion, increased laminin B1 transcript levels and synthesis of laminin polypeptides. Treatment with retinoic acid, a known regulator of laminin gene expression, not only increased the gene expression of laminin but stimulated the blastocoel expansion without a significant increase in intracellular cAMP levels. These results indicate that laminin gene expression may play an important role in the process of blastocyst expansion in the mouse preimplantation embryos.

Animals↗
PubMed1990

Diagnosis of hepatocellular carcinoma by factor analysis.

We examined the usefulness of factor analysis for the diagnosis of hepatocellular carcinoma by analysis of the data obtained by radionuclide angiography. The data could be separated into two factors, a hepatic phase (hepatic artery and portal vein) and an arterial phase (aorta and kidney). In patients with hepatocellular carcinoma, the factor of the tumor is included in the arterial phase, so that the cancerous region could be differentiated from the noncancerous region. The ratio of the radioactivity of the cancerous region to the noncancerous region was used to estimate the blood flow of the tumor region.

Carcinoma, Hepatocellular↗
PubMed1990

Effects of cytokines on prostaglandin E and cAMP levels in human periodontal ligament fibroblasts in vitro.

The stimulation of PGE synthesis and cAMP production by cytokines have important physiological effects in many target tissues. The effects of interleukin-1 alpha and -1 beta, tumour necrosis factor-alpha and interferon-gamma on PGE and cAMP production by periodontal ligament fibroblasts were studied. Fibroblasts in the 4th-6th passage, grown and maintained in DMEM supplemented with 10% equine serum, were incubated with graded doses of the various cytokines for 0.25, 0.5, 1.2, 4, 24, 48 or 72 h. At the end of each incubation, PGE in the medium and the cellular content of cAMP were evaluated by a combined immunohistochemical microphotometric procedure, and conventional radiometric assays. The fibroblasts responded to all the cytokines with a dose- and time-related increase in the levels of PGE and cAMP. Such increases were inhibited by the inclusion of indomethacin in the medium. The addition of exogenous PGE reversed that inhibition in respect of cAMP production. Immunohistochemical localization showed PGE predominantly in the cytoplasm and cAMP in the nucleus. These findings indicate that: (1) human periodontal ligament fibroblasts respond to these cytokines by increased synthesis of PGE and the production of cAMP; and (2) the cAMP production is secondary to the PGE synthesis. They suggest that these cytokines may regulate the function of these fibroblasts in physiological remodelling of the periodontium, as well as in inflammatory reactions.

Biological Factors↗
PubMed1990

Identification and fine structure of proliferating hepatocytes in malignant and nonmalignant liver diseases by use of a monoclonal antibody against DNA polymerase alpha.

To analyze the process of liver regeneration and the initiation of hepatocellular carcinoma (HCC), we studied histochemically the morphologic features of proliferating parenchymal cells stained for DNA polymerase alpha (DPA), in 31 patients with various diseases, by use of a monoclonal antibody against DPA. In specimens from patients with acute viral hepatitis with confluent necrosis, most stained hepatocytes were small, with basophilic cytoplasm, and were located next to the necrotic areas. Under electron microscopy, stained granules were seen in the nucleus. Most stained hepatocytes had immature organelles. In specimens from patients with cirrhosis of the liver, the number of stained hepatocytes greatly differed in different pseudolobules. In specimens from patients with adenomatous hyperplasia, stained hepatocytes, mostly small and basophilic, were found diffusely; electron microscopy showed slightly indented nuclei with a few organelles and less condensed chromatin than normal. In specimens from patients with HCC, most stained cancer cells were small and basophilic; electron microscopy showed indented nuclei with a few organelles and less than normal condensed chromatin. Staining showed that during regeneration, immature hepatocytes reentered the cell cycle and repaired a large necrotic area. It was conceivable that in the initiation of HCC, some small hepatocytes with indented nuclei and less condensed chromatin might become HCC cells.

Antibodies, Monoclonal↗
PubMed1990

An incidence survey of battered children in two elementary schools of Seoul.

Among the 1,142 girls and boys aged 9 to 11 years, 8.2% were seriously battered, 58% were mildly battered and 33.8% were unbattered during the past year. Child battering was more serious in families in the lower social strata, with poor living conditions, in broken families such as those with stepparents or absent mothers, and where parents were unskilled workers or unemployed. Finally, child battering was closely related to all other forms of family violence.

Adaptation, Psychological↗
PubMed1990

Activation of intracellular pathways with forskolin and phorbol ester increases LHRH mRNA level in the rat hypothalamus superfused in vitro.

Two intracellular signal transduction mechanisms such as cAMP-protein kinase a and phosphatidylinositol (PI) turnover-protein kinase c are known to be dually involved in the regulation of luteinizing hormone-releasing hormone (LHRH) release. However, it is not yet evident that the activation of two intracellular pathways affects the LHRH gene expression. The present study aims, therefore, to determine whether the activation of two intracellular pathways affects changes in LHRH mRNA. To this end, we took advantage of an in vitro superfusion system, where rat hypothalamic tissues were superfused with media containing forskolin (FKN) and/or phorbol-12-myristate-13-acetate (PMA). Superfusates were collected at 10-min intervals and LHRH release was determined by radioimmunoassay. After a 2-h superfusion period, the post-superfusion hypothalami were recovered and poly (A) RNA fractions were isolated. Alterations in LHRH mRNA in response to FKN and/or PMA were determined by an RNA-blot hybridization assay using a 32P-end-labeled LHRH oligonucleotide (29-mer) probe. In vitro perfusion of hypothalamic fragments with PMA and/or FKN stimulated LHRH release as well as LHRH mRNA. The combined infusion of FKN and PMA did not produce an additive effect on the LHRH mRNA levels, but it was effective in synergistically increasing LHRH secretion in vitro. These data clearly demonstrate that the biosynthetic machinery of LHRH is influenced by activation of two intracellular pathways, both cAMP-protein kinase a and phosphatidyl-inositol turnover-protein kinase c, indicating the transsynaptic regulation of hypothalamic LHRH gene expression.

Animals↗
PubMed1990

Fatty liver change as a result of hepatic artery infusion chemotherapy.

Direct hepatic arterial infusion of floxuridine (FUDR) (Roche Laboratories, Division of Hoffman-LaRoche Inc., Nutley, NJ, U.S.A.) has been used extensively in the treatment of metastases of colorectal tumors to the liver. The effectiveness of infusion and tolerance of the chemotherapy has been improved utilizing a totally implantable infusion pump delivery system. However, unequal distribution of drug infusion may occur to different parts of the liver parenchyma as demonstrated by hepatic arterial infusion scintigraphy (HAPS). We present a case of such unequal perfusion in which fatty metamorphosis of the liver occurred in the overperfused liver segment after FUDR therapy. The liver parenchymal changes were followed by serial computerized tomography scans and proven by biopsy during a minilaparotomy. Serial HAPS examinations show redirection of subsequent infusion to the opposite liver lobe due to parenchymal damage and vascular sclerosis. The importance of uniform liver perfusion and a rare dose-related effect of FUDR on liver parenchyma are thereby demonstrated.

Colonic Neoplasms↗
PubMed1990

Open reduction and interfragment wire fixation of comminuted nasal fractures.

Manual reduction is the first choice for all types of acute nasal fractures; open reduction is the choice for fractures that do not respond to manual reduction or complicated fractures at the base of the nasal pyramid. From 1968 to 1986, 564 cases of nasal fractures were treated at the Department of Plastic and Reconstructive Surgery, Jikei University School of Medicine, Tokyo. Of these, 241 were acute nasal fractures, 52 of which were associated with facial bone fractures. Deviated types of fractures that cannot be correctly repositioned by manual reduction and some depressed fractures often require a surgical approach for reduction and fixation. In our series of 241 patients with acute nasal fractures, 43 (18%) were treated by open reduction and fixed with soft stainless steel wires.

Adolescent↗
PubMed1990

Depressive episodes and dysphoria resulting from conjugal bereavement in a prospective community sample.

Using three waves of interviews from the New Haven Epidemiologic Catchment Area Program, the authors contrast the extent and nature of depressive episodes and dysphoria between newly bereaved (N = 39) and married (N = 1,047) respondents age 45 and older. Bereavement greatly increased the risk of both conditions. This observation did not appear to be an artifact because psychosocial risk factors were similar for the bereaved and married groups. Bereavement increased the risk for a depressive episode more among respondents who reported no prior dysphoria than among those who did. Among those meeting criteria for depression, the bereaved reported symptoms similar to those of the married group except for significantly fewer reports of guilt.

Adult↗
PubMed1990

Carney's triad with recurrent gastric leiomyoblastoma.

The triad of gastric leiomyoblastoma, extra-adrenal paraganglioma, and pulmonary chondroma was first described by Carney in 1977. Fewer than 30 patients with this syndrome have since been reported. In most patients the initial lesion has been a gastric leiomyoblastoma. The patient we describe had recurrences of a gastric leiomyoblastoma 15 and 17 years, respectively, after the initial gastric resection. Subsequently, multiple pulmonary lesions were excised and confirmed to be chondromas, but no evidence of a paraganglioma has yet been identified. Gastric leiomyoblastomas in patients with Carney's triad frequently recur; however, the prognosis is quite favorable in contrast to that of sporadic cases. Whenever a patient with one of the classical lesions of Carney's triad is encountered, the possibility of this unusual syndrome should be considered. The evaluation and follow-up of these patients should include a search for the other two components.

Adult↗
PubMed1990

Study duration for clinical trials with survival response and early stopping rule.

A comparative clinical trial with built-in sequential stopping rules allows earlier-than-scheduled stopping, should there be a significant indication of treatment difference. In a clinical trial where the major outcome is time (survival time or response) to a certain event such as failure, the design of the study should determine how long one needs to accrue patients and follow through until there is a sufficient number of events observed during the entire study duration. This paper proposes a unified design procedure for group sequential clinical trials with survival response. The time to event is assumed to be exponentially distributed, but the arguments extend naturally to the proportional hazards model after suitable transformation on the time scale. An example from the Eastern Cooperative Oncology Group (ECOG) is given to illustrate how this procedure can be implemented. The same example is used to explore the overall operating characteristics and the robustness of the proposed group sequential design.

Biometry↗
PubMed1990

Anxiety disorders during acute bereavement: risk and risk factors.

Forty-four percent of bereaved spouses reported at least one type of anxiety disorder during the first year of bereavement in a survey of a representative sample composed of a subgroup (N = 48) assessed 6 months after bereavement and another subgroup (N = 54) assessed 12 months after bereavement. The bereaved spouses experienced 6-month prevalence rates for panic disorder and generalized anxiety disorders that were higher than community prevalence rates for the same metropolitan area (p less than .01). Past personal history of anxiety disorder was an independent risk factor (p less than .05), and anxiety disorders were associated with severe grief (p less than .01) and depression (p less than .05). The large overlap of anxiety disorders with major depression observed in this study indicates that the estimated rates of anxiety disorder are not independent of major depression in most cases and raises questions about whether the anxiety disorders of bereavement are prodromal, concomitant, or residual with respect to major depression.

Adult↗
PubMed1989

Unidirectional transfer of broad host-range plasmid R1162 during conjugative mobilization. Evidence for genetically distinct events at oriT.

A segment of R1162 DNA containing genes for conjugative mobilization (Mob) and the origin of transfer (oriT) was integrated into the Escherichia coli chromosome. Bacterial genes were transferred in a polar fashion during conjugative mobilization of the integrated segment by a self-transmissible plasmid vector. The direction of transfer, together with the properties of mutated derivatives of oriT, indicate that initial cleavage of oriT, and subsequent religation after transfer, entail different mechanisms that can be distinguished genetically.

Base Sequence↗
PubMed1989

Implications of hyperechoic lesions in small hepatocellular carcinoma.

Of 34 solitary small hepatocellular carcinomas (HCC) 2 cm in diameter or less, 13 with hyperechoic lesions were observed serially by sonography, and 11 of these were examined histologically. Serial examination showed that hypoechoic areas appeared at the periphery of or within, the hyperechoic tumor, and that these areas expanded more with tumor growth than the hyperechoic areas as if compressing or displacing the existing hyperechoic areas. Histologically, the hyperechoic lesions were composed mostly of well-differentiated cancer cells containing fat droplets, whereas the hypoechoic lesions were composed of cancer cells without fat droplets. In the two tumors that were formed almost completely of cancer cells showing fatty metamorphosis, cancer cells without fat droplets proliferated mainly in the periphery of the tumor. These findings suggest that, in hyperechoic HCC, cancer cells with fat droplets appear in the early stage of HCC, and probably change into concer cells without fat droplets by the time that a certain tumor size is reached, with gradual displacement by the latter type of cell during tumor growth.

Biopsy↗