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Biomedical subjects

Y K Kim

Publications and source records attributed to Y K Kim.

At least 91 records · Page 5Linked to original sources

Treatment of mandible fractures using low-profile titanium miniplates: preliminary study.

This study evaluated the short-term results of patients treated with low-profile titanium miniplates for fractures of the mandible. Thirty-one fractures of the mandible in 23 patients were treated by open reduction and internal fixation using thin, low-profile miniplates and 1.3-mm self-threading screws. Duration of intermaxillary fixation ranged from 0 to 25 days. Patients were evaluated for complications during a follow-up period ranging from 6 to 24 months. Seven patients (30.4 percent) experienced complications. These included infection (n = 1), premature occlusal contact (n = 1), wound dehiscence (n = 1), temporomandibular joint disorder (n = 1), and paresthesia (n = 3). All complications were minor and adequately managed with incision and drainage, medication, and elastic traction. Low-profile titanium miniplates can be adequately used for internal fixation in selective mandibular fractures. Advantages of these types of plates include comfort due to the thinness of miniplates and ease of application.

Adolescent↗

Salviae radix extract prevents cisplatin-induced acute renal failure in rabbits.

The present study was carried out to determine if salviae radix extract (SRE) exerts a beneficial effect against cisplatin-induced renal failure in rabbits. Rabbits were pretreated with SRE orally for 7 days, followed by cisplatin injection (5 mg/kg i.p.). Cisplatin injection caused a reduction in GFR, which was accompanied by an increase in serum creatinine levels. The fractional Na+ excretion was increased by cisplatin injection. PAH uptake by renal cortical slices was inhibited by the administration of cisplatin. Such changes were prevented by SRE pretreatment. Cisplatin injection increased lipid peroxidation, which was prevented by SRE pretreatment. The protective effect of SRE was supported by morphological studies. Cisplatin injection reduced renal blood flow that was not affected by SRE pretreatment. Cisplatin treatment in vitro in renal cortical slices increased LDH release and lipid peroxidation, which were prevented by 0.05% SRE. These results indicate that lipid peroxidation plays a critical role in cisplatin-induced acute renal failure. SRE exerts a protective effect against renal cell injury induced by cisplatin, and its effect may be attributed to its antioxidant action. However, the underlying mechanism by which SRE has antioxidant action remains to be defined.

Acute Kidney Injury↗

Tectorigenin, an isoflavone of Pueraria thunbergiana Benth., induces differentiation and apoptosis in human promyelocytic leukemia HL-60 cells.

Cytotoxic effects of six isoflavonoids, tectorigenin, glycitein, tectoridin, glycitin, 6''-O-xylosyltectoridin, and 6''-O-xylosylglycitin isolated from the flower of Pueraria thunbergiana Benth. together with genistein, a known differentiation and apoptosis inducer, were examined. Among these isoflavonoids, tectorigenin and genistein exhibited cytotoxicity against various human cancer cells; glycitein showed only mild cytotoxicity. These results suggest that the isoflavone structure and 5-hydroxyl group are crucial for the cytotoxic properties and that glycosides are inactive. Moreover, tectorigenin induced differentiation of human promyelocytic leukemia HL-60 cells to granulocytes and monocytes/macrophages, and caused apoptotic changes of DNA in the cells, as did genistein. Tectorigenin also inhibited autophosphorylation of epidermal growth factor (EGF) receptor by EGF and decreased the expression of Bcl-2 protein, with less activity than genistein. From these results, tectorigenin may be a possible therapeutic agent for leukemia.

Anti-Inflammatory Agents, Non-Steroidal↗

Effect of risperidone on serum cytokines.

A variety of cytokines are dysregulated in schizophrenia, and some antipsychotic drugs effect cytokines. In order to examine the effect of risperidone on plasma cytokines, we measured the serum level of IL-1b, IL-2, IL-6, IL-12, and INF-g during acute states of illness, and after 4 weeks of treatment with risperidone in 19 schizophrenic patients. The patients' psychopathology was assessed by PANSS. Plasma IL-12 levels increased significantly after 4 weeks of treatment (p = .002). Plasma IL-b, IL-2, IL-6, and INF-g levels were not significantly different before and after treatment. There were no significant correlations between the changes in cytokine levels and the changes in PANSS scores. Increased IL-12 may contribute to activation of immune responses during treatment with risperidone. IL-12 may play an important role in immune responses related to neuropsychiatry.

Acute Disease↗

Epidemiologic and clinical survey of Behcet's disease in Korea: the first multicenter study.

The prevalence of Behcet's disease is the highest in the East Asian and the Mediterranean countries. Behcet's disease is also distributed in the Asian countries, but the nationwide survey has not been performed in Korea yet. The Korean Study Group for Behcet's Disease, founded in 1999, conducted a multicenter, retrospective survey on epidemiologic and clinical features of the patients with Behcet's disease from 20 hospitals around the nation from 1997 to 1999. Of 3,497 patients, 1,527 were classified into complete or incomplete type of Behcet's disease according to the revised Shimizu's classification. The sex ratio was 1:1.75 with the female predominance. Geographical distribution showed the highest frequency in Seoul (38.5%). Clinically, 98.8% had oral ulcers, 83.2% had genital ulcers, 84.3% had skin lesions and 50.9% had ocular lesions. As for the minor clinical manifestations, articular symptoms were the most frequent. The pathergy test showed positive in 15.4% of patients and revealed a higher positive rate in males (20.2%) than in females (12.7%). In conclusion, we performed the first multicenter study on Behcet's disease in Korea and revealed the female predominance, higher frequency of ocular lesions, and lower positivity of pathergy test in the patients.

Adolescent↗

Acid secretion from a heterotopic gastric mucosa in the upper esophagus demonstrated by dual probe 24-hour ambulatory pH monitoring.

Heterotopic gastric mucosa in the upper esophagus is frequently found during endoscopic examination. Although most patients with heterotopic gastric mucosa of the upper esophagus, referred as inlet patch, are asymptomatic, symptomatic patients with complications resulting from this ectopic mucosa have also been reported. Acid secretion by the inlet patch has been suggested in some reports. We report a case of heterotopic gastric mucosa in the upper esophagus, with secretion of acid, demonstrated by continuous ambulatory pH monitoring, and the improvement of pharyngeal symptoms after the use of a proton pump inhibitor.

Adult↗

A case of hereditary angioedema associated with idiopathic hypoparathyroidism.

Hereditary angioedema is a rare autosomal dominant disease characterized by the edema of subcutaneous tissues, respiratory tract and bowel. It is caused by the deficiency of C1 esterase inhibitor. Hereditary angioedema may be associated with autoimmune diseases, such as systemic lupus erythematosus, rheumatoid arthritis, autoimmune thyroiditis and glomerulonephritis. We report a 34-year-old male patient with hereditary angioedema who developed idiopathic hypoparathyroidism. Autoimmunity seems to be an important basis of this association and it might be caused by the immune dysfunction due to decreased level of complements; nevertheless, a casual association could not be excluded. To our knowledge, this is the first report of hereditary angioedema in association with idiopathic hypoparathyroidism in the medical literature.

Adult↗

Linkage between bronchial responsiveness to methacholine and gene markers of IL-4 cytokine gene cluster and T-cell receptor alpha/delta gene complex in Korean nuclear families.

BACKGROUND: Several candidate genes have been reported to be linked to intermediate phenotypes of asthma in Caucasian populations. OBJECTIVE: To evaluate linkage between phenotypes of asthma and gene markers of high affinity IgE receptor-beta gene (D11S97), IL-4 cytokine gene cluster (IL-4R1), and T-cell receptor alpha/delta gene complex (D14S50) in Korean nuclear families. METHODS: Nuclear families (127 probands and their 130 siblings) for the linkage analysis were ascertained through asthmatic children. Linkages between total serum IgE response, skin responses to common aeroallergens, and bronchial responsiveness to methacholine were performed using a sib-pair approach. RESULTS: The square difference of the slope of the dose-response curve (DRS) between sib-pairs with two IL-4R1 identical alleles was smaller than with one or with neither IL-4R1 identical allele (P = 0.004). As for D14S50, the differences of DRS between sib-pairs with two identical alleles and with one identical allele were smaller than with neither identical alleles (P = 0.01). As for D11S97, no significant differences were observed among the groups with identical alleles of two, one or zero. With regard to total serum IgE levels, no significant linkage was found between this phenotype and the above three gene markers. As for skin responses to common aeroallergens, significant evidence was obtained to establish a linkage between this phenotype and the marker IL-4R1 (P = 0.01). However, no significant linkage was found between this phenotype and the markers D11S97 and D14S50. CONCLUSION: The expression of bronchial responsiveness to methacholine may be influenced by genetic factors in the IL-4 cytokine gene cluster and/or T-cell receptor alpha/delta gene complex, but the genetic influence of the FcepsilonRI-beta gene may be minimal in the expression of bronchial responsiveness in Korean nuclear families.

Adolescent↗

HLA-DRB1*07 may have a susceptibility and DRB1*04 a protective effect upon the development of a sensitization to house dust mite Dermatophagoides pteronyssinus.

BACKGROUND: IgE responses to house dust mite-derived allergens seem to be the most important in the development of atopic asthma and rhinitis, but it has been difficult to demonstrate genetic control of the IgE response to the allergens. OBJECTIVE: This study was undertaken to investigate the association between sensitization to house dust mite, D. pteronyssinus (DP), and genotypes of HLA-DRB1 alleles. METHODS: DNAs were extracted from two groups of unrelated Koreans: (1) 178 with sensitization to DP; and (2) 99 age-matched non-atopic controls. Genotypes of the HLA-DRB1 alleles were determined using polymerase chain reaction (PCR)-based methods. RESULTS: The frequency of HLA-DRB1*07 was significantly increased in the DP-sensitive subjects compared with the controls (15.7% vs 4.0%, P = 0.009). Conversely, the frequencies of HLA-DRB1*04 and *14 were decreased in the DP-sensitive subjects compared with the controls (27.5% vs 45.5%, P = 0.002; 13.5% vs 24.2%, P = 0.02). Of the DRB1*04 alleles, DRB1*0403 was significantly decreased in the DP-sensitive subjects compared with the controls (3.9% vs 13.1%, P = 0.005). No significant differences were found in the distributions of the other HLA-DRB1 alleles between the two groups. CONCLUSION: HLA-DRB1*07 may have a susceptibility, and DRB1*04 and DRB1*14 may have a protective effect, upon the development of a sensitization to DP.

Adolescent↗

Antiangiogenic effect of KR31372 in rat sponge implant model.

A rat sponge implant model was used to examine the antiangiogenic effect of KR31372. Topical administration of angiotensin II (AII, 100 ng, daily) into the sponges enhanced the basal sponge-induced neovascularization, leading to higher clearance of (99m)Tc, increased retention of dye in the vessels, and increased numbers of blood vessels. These AII-induced changes were significantly suppressed by oral administration of KR31372 (1 mg/kg for 7 days). Angiogenic effect of recombinant human VEGF(165) (200 ng) was modestly higher than that of AII, which was also significantly inhibited by KR31372. KR31372-mediated suppression of (99m)Tc clearance was reversed by glibenclamide. Levcromakalim showed a modestly suppressive effect on the AII-induced angiogenesis. In conclusion, KR31372 exerted a strong inhibitory effect on the sponge-induced neovascularization, in part, through mediation of glibenclamide-sensitive K(+) channel activation. It is suggested that it may have therapeutic potential in the treatment of angiogenic disorders.

Angiogenesis Inhibitors↗

Prodigiosin blocks T cell activation by inhibiting interleukin-2Ralpha expression and delays progression of autoimmune diabetes and collagen-induced arthritis.

Prodigiosin (PDG) was previously reported to be a T cell-specific immunosuppressant. Here we describe the mechanism of action of PDG in T cells and the effect of PDG on autoimmune diseases. PDG selectively suppresses concanavalin A (Con A)-induced T cell proliferation, but has little effect on lipopolysaccharide-induced proliferation of B cells and nitric oxide production of macrophages. Although PDG does not block interleukin (IL)-2 production, it efficiently inhibits interleukin-2 receptor alpha-chain (IL-2Ralpha) expression, and this results in a disruption of the IL-2/IL-2R signaling pathway, on which a great part of the regulation of T cell activation depends. PDG blocks T cell differentiation into effector helper T cells secreting interferon-gamma and IL-4 as well as into effector cytotoxic T lymphocytes expressing perforin, which is at least in part resulting from inhibition of the IL-2/IL-2R signaling. PDG indirectly blocks signal transducer and activator of transcription activation by inhibiting cytokine signalings in Con A-activated T cells, although it does not inhibit the activation of nuclear factor-kappaB, nuclear factor of activated T cells, and activator protein-1. As direct evidence of immunosuppression in vivo, we show that PDG markedly reduced blood glucose levels and cellular infiltration into the pancreatic islets in nonobese diabetic mice, and that it also delays the onset of collagen-induced arthritis in DBA/1 mice. In conclusion, our results demonstrate that PDG has a unique mode of action, namely, that it blocks T cell activation by inhibiting primarily IL-2Ralpha expression in the IL-2/IL-2R signaling, and show that this compound represents a promising immunosuppressant candidate for the treatment of autoimmune diseases.

Animals↗

[Social status and role of students entering Jejoongwon: focus on Kyum-Rae Lee].

This study considers the social class and social role of the entering students of Jejoongwon at that time in light of its very first medical graduate, Kyum-Rae Lee. Foremost, Kyum-Rae Lee was confirmed to have been from a middle-class family. However, unlike other chungin-class families, his family belonged to the minority. He seemed to have entered medical school to seek opportunity to move up in social class by taking advantage of special government provisions, which allowed him to learn English and Western medicine. Afterwards, he performed heroic services in the peasant-war, proceeded up to administration and participated in the modernization of Great Han Empire. With his knowledge of Western concepts, he became involved in numerous social activities, such as organizing the Enlightenment Society and leading the Enlightenment Movement. In much the same way, most early students were from low-class background with exceptional personal abilities and were able to pass aptitude examinations. Such achievements allowed them to apply for positions in the military and administrative management. Ten years later, medical education to train medical professionals was revived with changes in attitudes of people of Chosun Dynasty toward Western medicine and with creation of formal medical study.

Education, Medical↗

Association of castration-dependent early induction of c-myc expression with a cell proliferation of the ventral prostate gland in rat.

The protooncogene c-myc is known to be associated with both cell proliferation and apoptosis. The possible cellular affects of castration on the ventral prostate gland of rat as well as the relationship to a castration induced c-myc expression were examined. Levels of c-myc mRNA in the ventral prostate gland peaked at 6 h (early induction) and 48 h (late induction) after castration, respectively. Castration-induced DNA fragmentation was not observed at an early induction of c-myc mRNA. DNA fragmentation appeared to be testosterone-dependent. On the other hand, cellular DNA synthesis measured by [3H]thymidine uptake in the ventral prostate gland was increased to maximum at 6 h after castration. These results suggest that an early induction of c-myc mRNA in ventral prostate gland after castration is closely associated with cell proliferation of the gland.

Animals↗

Polypyrimidine tract-binding protein inhibits translation of bip mRNA.

Translation initiation of human Bip mRNA is directed by an internal ribosomal entry site (IRES) located in the 5' non-translated region. No trans-acting factor possibly involved in this process has as of yet been identified. For the encephalomyocarditis virus and other picornaviruses, polypyrimidine tract-binding protein (PTB) has been found to enhance the translation through IRES elements, probably by interaction with the IRES structure. Here, we report that PTB specifically binds to the central region (nt 50-117) of the Bip 5' non-translated region. Addition of purified PTB to rabbit reticulocyte lysate and overexpression of PTB in Cos-7 cells selectively inhibited Bip IRES-dependent translation. On the other hand, depletion of endogenous PTB or addition of an RNA interacting with PTB enhanced the translational initiation directed by Bip IRES. These suggest that PTB can either enhance or inhibit IRES-dependent translation depending on mRNAs.

5' Untranslated Regions↗

Enzyme modification of starch granules: formation and retention of cyclomaltodextrins inside starch granules by reaction of cyclomaltodextrin glucanosyltransferase with solid granules.

Cyclomaltodextrin glucanosyltransferase (CGTase) was adsorbed into starch granules and allowed to react at 37 degrees C. The reaction was conducted with the granules removed from an aqueous environment, but containing 50% w/w water inside the granule. Reaction for 20 h gave a maximum of 1.4%, w/w of cyclodextrins (CDs) inside the granule. Waxy maize and maize starches gave the highest amounts of CDs (1.3 and 1.4%, respectively), with tapioca and amylomaize-7 starches giving about 50% less (0.9 and 0.6%, respectively). Reaction of a combination of CGTase and isoamylase with solid starch granules gave a 2.6-fold increase in the formation of CDs, with a maximum yield of 3.4 and 100% retention inside waxy maize starch granules.

Adsorption↗

Relationships between interleukins, neurotransmitters and psychopathology in drug-free male schizophrenics.

It has been postulated that altered interleukin (IL) regulation may be involved in the pathogenesis of schizophrenia. We therefore investigated the relationships between interleukins, neurotransmitters, and psychopathology in schizophrenia. IL-1beta, IL-2, IL-6, homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5-HIAA) were measured in the plasma of neuroleptic-free male schizophrenics in comparison to age-matched healthy male controls (n=25 each). The patients' psychopathology was assessed by the Scale for the Assessment of Positive and Negative Symptoms (SAPS, SANS). The above variables were measured during acute states of illness and after eight weeks of treatment with haloperidol. The plasma levels of IL-2 and HVA were significantly higher in patients compared to controls. In schizophrenic patients, there were significant correlations between IL-2 and HVA, IL-2 and SAPS, and HVA and SAPS during the acute state of illness. The level of IL-6 was significantly correlated to SANS and duration of illness. In schizophrenic patients, the plasma levels of IL-2 and HVA were significantly lowered after treatment with haloperidol. Changes in IL-2 and HVA significantly correlated to those in HVA and SAPS, respectively. These results strongly suggest that the cytokines may modulate dopaminergic metabolism and schizophrenic symptomatology in schizophrenia.

Adult↗