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Biomedical subjects

Y C Kim

Publications and source records attributed to Y C Kim.

At least 91 records · Page 5Linked to original sources
PubMed2000

Repression of hspA2 messenger RNA in human testes with abnormal spermatogenesis.

OBJECTIVE: To evaluate the messenger RNA (mRNA) expression of hspA2 in testes of infertile men with azoospermia. DESIGN: Prospective study. SETTING: Center for Reproduction and Genetics, Pundang Je-Saeng General Hospital, Dae-Jin Medical Center, Korea. PATIENT(S): Azoospermic patients (n = 15) undergoing testicular biopsy for pathologic evaluation were selected. INTERVENTION(S): After pathologic evaluation, testicular biopsy specimens were subdivided into three groups: group 1, normal spermatogenesis (n = 5); group 2, spermatocyte arrest (n = 5); and group 3, Sertoli cell-only syndrome (n = 5). The levels of hspA2 mRNA expression were compared in testes of group 1, group 2, and group 3 with the use of a competitive reverse transcription polymerase chain reaction (RT-PCR) technique. MAIN OUTCOME MEASURE(S): Comparison of hspA2 mRNA levels in testes. RESULT(S): On competitive RT-PCR analyses for hspA2 mRNA, significant hspA2 expression was observed in group 1, whereas a very low level of hspA2 was expressed in groups 2 and 3. CONCLUSION(S): This study demonstrates that hspA2 gene expression is down-regulated in human testes with abnormal spermatogenesis, which in turn suggests that the hspA2 gene might play a specific role during meiosis in human testes.

Cell Cycle↗
PubMed2000

Neuroprotective phenylpropanoid esters of rhamnose isolated from roots of Scrophularia buergeriana.

Four phenylpropanoid esters of rhamnose, buergerisides A1, B1, B2 and C1 were isolated from roots of Scrophularia huergeriana MIQ. (Scrophulariaceae), and were characterized as 2-O-acetyl-3,4-di-O-(E)-p-methoxycinnamoyl-alpha-L-rhamnopyranosid e, 2-O-acetyl-3-O-(E)-p-methoxycinnamoyl-alpha-L-rhamnopyranoside, 2-O-acetvl-3-O-(Z)-p-methoxycinnamoyl-alpha-L-rhamnopyranosi de and 4-O-(E)-p-methoxycinnamoyl-alpha-L-rhamnopyranoside, respectively. In addition, six known phenylpropanoids were authenticated as: (E)-cinnamic acid, (E)-p-methoxycinnamic acid, (E)-p-methoxycinnamic acid methyl ester, (E)-p-coumaric acid, (E)-caffeic acid, (E)-ferulic acid and a phenylalcohol, 2-(3-hydroxy-4-methoxyphenyl)ethanol. These ten phenylpropanoids all attenuated glutamate-induced neurotoxicity when added to primary cultures of rat cortical cells in a dose-dependent manner. These results demonstrate that phenylpropanoids isolated from S. buergeriana may exert significant protective effects against glutamate-induced neurodegeneration in primary cultures of cortical neurons.

Animals↗
PubMed2000

Different cutoff values of Cyfra 21-1 for cavitary and noncavitary lung cancers.

STUDY OBJECTIVES: Cell lysis and tumor necrosis release cytokeratin, a tumor marker of lung cancer, into the serum. The serum cytokeratin level can also be elevated in benign cavitary lung diseases. The purpose of this study was to evaluate whether Cyfra 21-1 can differentiate malignant lung diseases from benign diseases with cavitary lesions. DESIGN: This study is a retrospective review of the case records of patients with lung lesions seen during a 4-year period from January 1993 to May 1996. SETTING AND PATIENTS: Serum Cyfra 21-1 levels were measured in 306 patients with lung cancer (n = 143) or benign lung disease (n = 163). The patients were grouped according to radiologic evidence of cavitary lung lesions. Lung cancer included both non-small cell (n = 123) and small cell (n = 20) lung cancers, and the benign diseases include tuberculosis (n = 87), abscess (n = 26), pneumonia (n = 4), and others (n = 46). MEASUREMENTS AND RESULTS: Although Cyfra 21-1 clearly differentiated cavitary lung cancer (15.0, 9.1-29.8 ng/ml, median and interquartile range, n = 39) from benign cavitary disease (P < 0.001), and noncavitary lung cancer from benign noncavitary disease (1.7, 0.9-2.6 ng/ml, n = 108, P < 0.001), it could not differentiate noncavitary lung cancer (5.0, 2.1-12.4 ng/ml, n = 104) from benign cavitary diseases (3.3, 1.4-8.3 ng/ml, n = 55, P = 0.45). CONCLUSIONS: Serum Cyfra 21-1 is a useful tumor marker for differentiating benign from malignant lung diseases. However, different cutoff values are needed, depending on the presence of cavitary lesions. We recommend cutoff values of 30 ng/ml for cavitary lung diseases and 6 ng/ml for noncavitary lung diseases. If there are no radiologic data, a cutoff value of 15 ng/ml is recommended.

Adult↗
PubMed2000

Polymethoxyflavonoids from Vitex rotundifolia inhibit proliferation by inducing apoptosis in human myeloid leukemia cells.

Three polymethoxyflavonoids from the fruit of Vitex rotundifolia, namely 2',3',5-trihydroxy-3,6,7-trimethoxyflavone (Vx-1), vitexicarpin (Vx-5) and artemetin (Vx-6), were tested for their antiproliferative activity in human myeloid leukemia HL-60 cells. They showed a dose-dependent decrease in the growth of HL-60 cells. The concentrations required for 50% inhibition of the growth (IC50) after 96 h were 4.03 microM, 0.12 microM and 30.98 microM for Vx-1, Vx-5 and Vx-6, respectively. Treatment of HL-60 cells with the flavonoids induced morphological changes that are characteristic of apoptosis. We judged the induction of apoptosis by the detection of DNA fragmentation in agarose gel electrophoresis and the degree of apoptosis was quantified by a double-antibody sandwich ELISA and by flow cytometric analysis. The C-3 hydroxyl and C-8 methoxyl groups were found not to be essential for the activity, but the C-3' methoxyl instead of hydroxyl group lowered the antiproliferative and apoptosis inducing activity. These results suggest that the polymethoxyflavonoids isolated from V. rotundifolia may be used as potential chemopreventive and chemotherapeutic agents.

Antineoplastic Agents, Phytogenic↗
PubMed2000

Pentoxifylline potentiates nitric oxide production in interleukin-1beta-stimulated vascular smooth muscle cells through cyclic AMP-dependent protein kinase A pathway.

In the present study, we observed that pentoxifylline (PTX) significantly augmented the nitric oxide (NO) production and the iNOS gene expression by interleukin-1beta (IL-1beta)-stimulated vascular smooth muscle cells (VSMCs). The enhancing effects of PTX on the IL-1beta-induced NO production was associated with an increased intracellular cyclic AMP (cAMP) levels, and the synergistic effects of PTX on the IL-1beta-induced NO production was blocked by cAMP-dependent protein kinase A (PKA) inhibitors. PKA inhibitors, KT5720 and H89, markedly decreased the augmented expression of iNOS gene whereas ODQ, a soluble guanylate cyclase inhibitor, did not affect the enhancing effect. In addition, the pretreatment with KT5720 or H89 abolished the increased translocation of the p65 subunit of NF-kappaB into the nucleus by PTX in the IL-1beta-stimulated VSMCs. These results suggest that enhancing effects of PTX on the iNOS gene expression in the IL-1beta-stimulated VSMCs is mediated predominantly through the activation of NF-kappaB via cAMP-dependent PKA pathway.

Animals↗
PubMed2000

Inhibitory effects of butanol fraction of the aqueous extract of Forsythia koreana on the nitric oxide production by murine macrophage-like RAW 264.7 cells.

The aim of this study was to investigate the effect of butanol fraction of the aqueous extract of Forsythia koreana fruits on the nitric oxide (NO) production and inducible nitric oxide synthesis (iNOS) gene expression in murine macrophage-like RAW 264.7 cells. Butanol fraction alone affected neither NO production nor iNOS gene expression in macrophage-like RAW 264.7 cells. However, the butanol fraction inhibited NO production and iNOS gene expression in RAW 264. 7 cells stimulated with interferon-gamma (IFN-gamma) and lipopolysaccharide (LPS). These findings suggest that inhibition of NO production by this butanol fraction in RAW 264.7 cells stimulated with IFN-gamma plus LPS was due to the suppression of iNOS gene expression.

Analysis of Variance↗
PubMed2000

Antihepatotoxic activity of bergenin, the major constituent of Mallotus japonicus, on carbon tetrachloride-intoxicated hepatocytes.

To determine the antihepatotoxic activity of bergenin from Mallotus japonicus, carbon tetrachloride (CCl4)-induced cytotoxicity in primary cultured rat hepatocytes has been adopted as an assay system. Bergenin significantly reduced the activities of glutamic pyruvic transaminase and sorbitol dehydrogenase released from the CCl4-intoxicated hepatocytes. The antihepatotoxicity of bergenin was also evidenced by elevating the activities of glutathione S-transferase and glutathione reductase, and content of glutathione in the CCl4-intoxicated hepatocytes. From these results, it is assumed that bergenin exerted antihepatotoxicity against CCl4-induced cytotoxicity through glutathione-mediated detoxification as well as free radical suppressing activity.

Alanine Transaminase↗
PubMed2000

Protective effects of bergenin, the major constituent of Mallotus japonicus, on D-galactosamine-intoxicated rat hepatocytes.

This study was designed to investigate the effects of bergenin against D-galactosamine-induced injury in primary cultured rat hepatocytes. Bergenin (100 microM) decreased the release of glutamic pyruvic transaminase and sorbitol dehydrogenase by 62 and 50%, respectively, into hepatocyte medium incubated for 14 h with 1.5 mM galactosamine. Decreased RNA synthesis by 1.5 mM galactosamine was recovered 2.5 times compared with that of control hepatocytes at 100 microM bergenin. Therefore, the present results suggest that bergenin show hepatoprotective effects against galactosamine-intoxicated rat hepatocytes by inhibiting the release of glutamic pyruvic transaminase and sorbitol dehydrogenase as well as by increasing RNA synthesis.

Alanine Transaminase↗
PubMed2000

Antiproliferative effects of alkaloids from Sedum sarmentosum on murine and human hepatoma cell lines.

The whole plant of Sedum sarmentosum (SS) has been traditionally used for the treatment of chronic viral hepatitis in China and South Korea. Certain hepatitis virus causes acute and chronic hepatitis and induces hepatocellular carcinoma (HC). In the present study, we examined whether the crude alkaloid fraction (CAF) of SS had any anticancer effects on hepatoma cell lines. Murine hepatoma (BNL CL. 2) and human hepatoma (HepG2) cell lines were cultured in the presence of CAF of SS at various doses (50-150 microg/ml) for 24 or 48 h. CAF caused a dose-dependent inhibition of cell proliferation without necrosis or apoptosis. Antiproliferative effects of CAF of SS were associated with an increase in the number of cells in the G1 phase of cell cycle. This study suggests that SS may improve survival of hepatoma patients via the inhibition of excessive growth of tumor cells.

Alkaloids↗
PubMed2000

Sedative activity of two flavonol glycosides isolated from the flowers of Albizzia julibrissin Durazz.

The flowers of Albizzia julibrissin are used as a sedative in oriental traditional medicine. The phytochemical study of this plant allowed the isolation of two flavonol glycosides, quercitrin (1) and isoquercitrin (2). The sedative activity of these compounds was evaluated, and both compounds 1 and 2 increased pentobarbital-induced sleeping time in dose-dependent manner in mice. These results support the use of the flowers of this plant as a sedative agent.

Animals↗
PubMed2000

Lavandulylflavonoids: a new class of in vitro apoptogenic agents from Sophora flavescens.

The root of Sophora flavescens has been reported to possess antitumor activity in Sarcoma 180, lymphoid leukemia 1210 and melanotic melanoma. We have isolated four cytotoxic flavonoids with a lavandulyl side-chain at C8 and tested for their effects on human myeloid leukemia HL-60 cells and human hepatocarcinoma HepG2 cells, in terms of inhibition of proliferation and induction of apoptosis. They showed potent antiproliferative effects with IC(50) values from 11.3 microM to 18.5 microM in HL60 cells and from 13.3 microM to 36. 2 microM in HepG2 cells. Treatment of HL-60 cells with the lavandulylflavonoids induced apoptosis in a dose-dependent manner. Apoptosis was judged by the detection of DNA fragmentation by agarose gel electrophoresis and the degree of apoptosis was quantified by a sandwich enzyme immunoassay. The hydration of C4"'C5"' double bond with or without C3 hydroxylation caused a complete loss of cytotoxicity. These results suggest that the lavandulyl side-chain is essential for the activity of the flavonoids isolated from S. flavescens which may be used as cancer chemotherapeutic and chemopreventive agents.

Apoptosis↗
PubMed2000

The effect of herpesvirus infection on the expression of cell adhesion molecules on cultured human dermal microvascular endothelial cells.

Cell-mediated immune response to herpes simplex virus (HSV) may be important in the pathogenesis of herpes keratitis, erythema multiforme or Behcet's disease. We examined whether herpesvirus infection regulates the expression of cell adhesion molecules on cultured human dermal microvascular endothelial cells (HDMEC) and the regulation of T-lymphocytes binding to HDMEC. The expression of intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), or E-selectin on HDMEC increased significantly after treatment with HSV-1, HSV-2, or measles virus on HDMEC. Anti-IL-1 alpha antibody or anti-TNF alpha antibody partially inhibited the expression of ICAM-1, VCAM-1, or E-selectin on HDMEC. The binding of T-lymphocytes to HDMEC increased significantly after the treatment of HSV-1 or measles virus on HDMEC. The binding of T-lymphocytes to HDMEC was significantly inhibited after 16 h of incubation following treatment with anti-ICAM-1 antibody, anti-IL-1 alpha antibody or anti-TNF alpha antibody to HDMEC. These study results suggest that HSV induces the increased expression of ICAM-1, or induction of VCAM-1 and E-selectin on HDMEC and that among these adhesion molecules, the expression of ICAM-1 on HDMEC mainly regulates the binding of T-lymphocytes to HDMEC. The data also suggest that IL-1 alpha or TNF alpha which was produced by HSV infected HDMEC may be related to these events.

Cell Adhesion↗
PubMed2000

Hepatoprotective diastereomeric lignans from Saururus chinensis herbs.

Two new diastereomeric sauchinones (2, 3), along with the known sauchinone (1), a phenylpropanoid (sarisan), and two known lignans (galbacin and saucernetin), were isolated from the n-hexane fraction of Saururus chinensis using reversed-phase HPLC. The stereostructures of the lignans, sauchinone A (2) and 1'-epi-sauchinone (3), were established by analysis of spectroscopic data. Incubation of cultured rat hepatocytes intentionally injured by CCl(4) with each of the compounds 1, 2, and 3 significantly reduced the levels of glutamic pyruvic transaminase released by the damaged hepatocytes.

Animals↗
PubMed2000

Cytotoxic lavandulyl flavanones from Sophora flavescens.

Two new lavandulylated flavanones, (2S)-2'-methoxykurarinone (1) and (-)-kurarinone (2), were isolated from the root of Sophora flavescens, together with two known lavandulyl flavanones, sophoraflavanone G (3) and leachianone A (4), and two known isoflavonoids, formononetin and l-maakiain. The structures of 1 and 2 were determined on the basis of optical rotation and spectral evidence and by comparison with known compounds. Compounds 1-4 exhibited cytotoxic activity against human myeloid leukemia HL-60 cells.

Antineoplastic Agents↗
PubMed2000

Nodular hidradenocarcinoma with prominent squamous differentiation: case report and immunohistochemical study.

We report the case of a 24-year-old woman with nodular hidradenocarcinoma on the scalp. While histopathology of the tumor showed a circumscribed, lobulated intradermal mass with prominent squamous differentiation, the immunohistochemical study with antibodies to cytokeratins, CAM 5.2 and 19, epithelial membrane antigen, carcinoembryonic antigen, S-100 protein and p53 all demonstrated positivity. These findings confirmed that the tumor was of eccrine sweat gland origin and it was thought to be a nodular hidradenocarcinoma differentiating toward the eccrine duct and/or secretory portions. She was treated with a wide local excision and no recurrence was observed 18 months after excision.

Adenocarcinoma↗
PubMed2000

Cyclic adenosine monophosphate inhibits ursolic acid-induced apoptosis via activation of protein kinase A in human leukaemic HL-60 cells.

This study was designed to investigate the effect of cAMP on ursolic acid-induced apoptosis of HL-60 cells. Ursolic acid decreased the viability of the cells in a dose-dependent manner, which was revealed as an apototic process characterized by ladder-pattern DNA fragmentation in agarose gel electrophoresis and segmented nuclei in DAPI-sulpharhodamin 101 staining. Ursolic acid-induced apoptosis of the cells was markedly inhibited by the addition of cAMP-elevating agents including DB-cAMP, CPT-cAMP, 8-Br-cAMP and forskolin. These results were further evidenced by the fact that inhibitors of cAMP-dependent protein kinase including H89 and KT5720 completely inhibited the cAMP-mediated rescue of HL-60 cells from ursolic acid-induced apoptosis. In addition, differentiating agents of the cells such as dimethyl sulfoxide and retinoic acid did not affect the ursolic acid-induced apoptosis of HL-60 cells. These results suggest that signaling pathway of cAMP-dependent activation of protein kinase A may affect the responsiveness of tumor cells upon ursolic acid.

Antineoplastic Agents, Phytogenic↗
PubMed2000

Granulomatous pyoderma gangrenosum: two unusual cases showing necrotizing granulomatous inflammation.

We present two cases of pyoderma gangrenosum (PG) with unusual histopathological findings. The main histopathological feature of PG is usually massive neutrophilic infiltration; the neutrophil is thus the cytologic hallmark of PG. The occurrence of vasculitis is controversial. In our patients, in contrast, biopsy specimens revealed extensive granulomatous inflammation with massive tissue necrosis throughout the entire dermis and subcutaneous tissue and vascular involvement simulating many other granulomatous diseases. However, there was no evidence of systemic disease. Our cases may therefore represent a histopathologically distinct subset of PG.

Adult↗