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991.
Clinical usefulness of human cytomegalovirus antigenemia assay after kidney transplantation 总被引:9,自引:0,他引:9
Kim CK Song JH Kim SM Peck KR Oh W Huh W Kim YG Kim SJ Joh JW Lee NY Park CG Hwang ES Cha CY Oh HY 《Transplantation》2003,75(12):2151-2155
BACKGROUND: Human (H) cytomegalovirus (CMV) infections are a major cause of morbidity and mortality among kidney transplants. We performed a prospective study to evaluate the clinical usefulness of HCMV antigenemia assay for preemptive treatment after kidney transplantation. METHODS: A total of 100 patients were followed up by HCMV antigenemia assay at posttransplantation weeks 1, 3, 5, 7, 9, 13, 17, and 21. Asymptomatic patients with positive antigenemia were observed without specific antiviral therapy. RESULTS: Most patients had been given cyclosporine A- and prednisolone-based immunosuppressive therapy (99.0%) and were HCMV seropositive before transplantation (99.0%). A positive antigenemia assay was detected in 41 patients among 97 eligible patients. Symptomatic CMV diseases were observed in 10 of 41 patients. HCMV infections were related to history of acute rejection and use of antithymocyte globulin. HCMV-related symptoms and signs were clearly correlated with the level of antigenemia. All patients who had an HCMV antigenemia titer of higher than 50 per 400,000 leukocytes developed HCMV-related symptoms and signs during the follow-up period. This criterion showed the highest positive predictive value and specificity in the development of symptomatic HCMV infection. CONCLUSIONS: Data suggest that HCMV antigenemia titer can be used as a useful guide to preemptive treatment of HCMV infection after kidney transplantation in HCMV-positive donor and recipient. 相似文献
992.
Park JO Lee SI Song SY Kim K Kim WS Jung CW Park YS Im YH Kang WK Lee MH Lee KS Park K 《Japanese journal of clinical oncology》2003,33(10):533-537
BACKGROUND: Objective tumor response is a common endpoint in daily practice as well as in clinical trials to evaluate the efficacy of anti-cancer agents. Traditionally, the standard World Health Organization (WHO) criteria has been adopted in these contexts. However, the recent development of new classes of anti-cancer agents and progress in imaging technology have required new methodology to evaluate response to treatment. Recently, the Response Evaluation Criteria in Solid Tumors Group (RECIST) proposed new guidelines using unidimensional measurement. Theoretically, the simple sum of the maximum diameters of individual tumors is more linearly related to cell kill than is the sum of the bidimensional products. To validate these new guidelines, we have compared the standard WHO response criteria with the new RECIST guidelines in the same patient population. METHODS: Data from 79 patients enrolled in eight prospective phase II studies at Samsung Medical Center were retrospectively re-analyzed to determine the concordance between the two response criteria. The two response criteria were applied separately, and the results were compared using the kappa statistic to test concordance for overall response rate. RESULTS: The overall response rate according to the WHO criteria was 31.6%. Using the RECIST criteria, nine patients were reclassified and the overall response rate was 30.4%. There was excellent agreement between the unidimensional and bidimensional criteria in 23 of 25 responses (92%). The kappa statistic for concordance for overall response was 0.91. CONCLUSIONS: We conclude that the new RECIST guidelines are comparable to the old response criteria in evaluating response in solid tumors. Moreover, the new guidelines are just as simple and reproducible in the measurement of response in daily practice as they are in clinical trials. 相似文献
993.
994.
The inhibition of histone deacetylase activity is known to induce morphological changes of transformed cells. In this study, we investigated the effect of the specific HDAC inhibitor, trichostatin A (TSA), on colon carcinoma cell lines. Treatment of human colorectal carcinoma cells, KM1214 and KM12SM, with TSA induced distinct morphological changes. Both cell lines, which normally piled up in layers without clear boundary, became more flattened, and formed monolayers with evident boundaries between cells, with concomitant increased actin filament organization. Cell-cell interaction was not affected much, based on expression level, membrane localization, and interaction of E-cadherin with beta-catenin. In contrast, syndecan-2 expression was dramatically reduced and it was correlated with the morphological changes of colon carcinoma cells. Consistently, downregulation of syndecan-2 expression by antisense cDNA clearly mimicked the morphological changes in KM12SM and reduced anchorage-independent growth of colon cancer cells. All these results indicate that reduced syndecan-2 expression correlates with TSA-induced morphological changes and reduced tumorigenic activity in colon carcinoma cells. 相似文献
995.
Secoiridoid glucosides with free radical scavenging activity from the leaves of Syringa dilatata 总被引:1,自引:0,他引:1
Activity-guided fractionation of the EtOAc and MeOH extract of the leaves of Syringa dilatata NAKAI furnished one free radical scavenger, the secoiridoid glucoside oleuropein together with ligstroside and an iridoid glucoside, syringopicroside. Oleuropein interacted with the stable free radical, 1,1-diphenyl-2-picrylhydrazyl (DPPH), and showed an IC(50) value of 40.4 microM. L-Ascorbic acid as a positive control showed an IC(50) value of 50.3 microM. 相似文献
996.
Oh H Kang DG Kwon TO Jang KK Chai KY Yun YG Chung HT Lee HS 《Phytotherapy research : PTR》2003,17(7):811-813
The bioassay-guided fractionation of the n-BuOH extract of Abeliophyllum distichum afforded acteoside (1), isoacteoside (2), rutin (3), and hirsutrin (4). Compounds 1-3 moderately inhibited the angiotensin I converting enzyme activity in a dose-dependent manner. Compounds 1-3 showed the 50% inhibitory concentration values of 228 micro g/mL, 290 micro g/mL, and 278 micro g/mL, respectively. 相似文献
997.
Inhibitory effects of the root cortex of Paeonia suffruticosa on interleukin-8 and macrophage chemoattractant protein-1 secretions in U937 cells 总被引:1,自引:0,他引:1
Oh GS Pae HO Choi BM Jeong S Oh H Oh CS Rho YD Kim DH Shin MK Chung HT 《Journal of ethnopharmacology》2003,84(1):85-89
In an effort to elucidate the mechanism of the anti-inflammatory effect of mudanpi, the root cortex of Paeonia suffruticosa Andrews (Ranunculaceae), we determined the effects of the methanolic extract of mudanpi (MEM) on the secretions of interleukin (IL)-8, a major mediator of acute neutrophil-mediated inflammation, and macrophage chemoattractant protein (MCP)-1, a major mediator of chronic macrophage-mediated inflammation, in human monocytic U937 cells stimulated with phorbol myristate acetate (PMA). MEM significantly inhibited PMA-induced secretions of IL-8 and MCP-1 proteins in a dose-dependent manner. The inhibition of these chemokines by MEM was due to its suppression of IL-8 and MCP-1 genes. In addition, 1,2,3,4,6-penta-O-galloyl-beta-D-glucose, one of major constituents isolated from MEM, inhibited PMA-induced secretions of IL-8 and MCP-1 proteins by its suppression of IL-8 and MCP-1 genes. Thus, one possible anti-inflammatory mechanism of mudanpi, an anti-inflammatory Chinese crude drug, may be to inhibit the secretions of inflammatory chemokines. 相似文献
998.
BACKGROUND: Attitudes toward the use of chemotherapy in patients with prostate carcinoma have changed as new therapeutics have demonstrated efficacy. This is important as randomized trials using chemotherapy are proposed. The authors used a questionnaire to investigate the attitudes of physicians in the New England area who care for patients with advanced prostate carcinoma. METHODS: A 15-question survey was developed and mailed in the year 2000. No monetary incentives were used to encourage return of surveys. Baseline demographic data were obtained, including type of practice and number of patients with prostate carcinoma seen. Urologists, radiation oncologists, and medical oncologists were asked whether they had recommended chemotherapy for patients with prostate carcinoma, what they perceived as the effectiveness of specific drugs, what concerns they had regarding chemotherapy, and the appropriateness of chemotherapy in three hypothetical patient scenarios. RESULTS: Of 1068 surveys that were delivered to practicing physicians, 232 surveys (22%) were returned and evaluable. Forty-six percent of respondents were urologists, 41% were medical oncologists, and 10% were radiation oncologists. Eighty-seven percent of respondents had recommended cytotoxic chemotherapy to their patients. Four agents were rated as moderately effective to very effective by 41-60% of respondents who rated effectiveness: estramustine, mitoxantrone, paclitaxel, and docetaxel. In three hypothetical patient scenarios of hormone-refractory prostate carcinoma, only one patient was judged as an appropriate candidate for chemotherapy. In a multivariate analysis, female physicians and physicians with practices comprised of > 25% patients with hormone-refractory prostate carcinoma were more likely to recommend chemotherapy. Concerns regarding severe toxicity and lack of benefit were among the most influential on respondent decisions to use chemotherapy. CONCLUSIONS: Most physicians who cared for patients with prostate carcinoma had recommended chemotherapy for patients with hormone-refractory disease. There were differences between specialties regarding the likelihood of recommending chemotherapy and clinical judgment regarding which patients were appropriate candidates for chemotherapy. 相似文献
999.
Kim IK Jung YK Noh DY Song YS Choi CH Oh BH Masuda ES Jung YK 《British journal of cancer》2003,88(6):910-917
TNF-related apoptosis-inducing ligand (TRAIL) is known to selectively induce apoptosis in various tumour cells. However, downstream-signalling of TRAIL-receptor is not well defined. A functional genetic screening was performed to isolate genes interfering with TRAIL-induced apoptosis using cDNA retroviral library. Bcl-X(L) and FLIP were identified after DNA sequencing analysis of cDNA rescued from TRAIL-resistant clones. We found that increased expression of Bcl-X(L), but not Bcl-2, suppressed TRAIL-induced apoptosis in tumour cells. Western blot and immunohistochemical analyses showed that expression of Bcl-X(L), but not Bcl-2, was highly increased in human breast cancer tissues. Exposure of MDA-MB-231 breast tumour cells to TRAIL induced apoptosis accompanied by dissipation of mitochondrial membrane potential and enzymatic activation of caspase-3, -8, and -9. However, SK-BR-3 breast tumour cells exhibiting increased expression level of Bcl-X(L) were resistant to TRAIL, though upon exposure to TRAIL, caspase-8 and Bid were activated. Forced expression of Bcl-X(L), but not Bcl-2, desensitised TRAIL-sensitive MDA-MB-231 cells to TRAIL. Similar inhibitory effects were also observed in other tumour cells such as HeLa and Jurkat cells stably expressing Bcl-X(L), but not Bcl-2. These results are indicative of the crucial and distinct function of Bcl-X(L) and Bcl-2 in the modulation of TRAIL-induced apoptosis. 相似文献
1000.
Trichostatin inhibits the growth of ACHN renal cell carcinoma cells via cell cycle arrest in association with p27, or apoptosis 总被引:5,自引:0,他引:5
Park WH Jung CW Park JO Kim K Kim WS Im YH Lee MH Kang WK Park K 《International journal of oncology》2003,22(5):1129-1134
We investigated the in vitro effect of trichostatin (histone deacetylase inhibitor) on cell proliferation, cell cycle regulation and apoptosis in renal cell carcinoma cell lines. Trichostatin significantly inhibited the proliferation of all six cell lines examined in dose-dependent manner with IC50 of about 125-250 nM. Trichostatin (72-h incubation) induced a G1 phase arrest in ACHN, Caki-1, Caki-2 and Renca cell lines and a G2-M phase arrest in A498 cells. When we examined the effects of this drug on ACHN cells, trichostatin decreased the levels of CDK4, CDK6, cyclin D1 and cyclin A proteins. p27 protein was increased by trichostatin. In addition, trichostatin markedly enhanced the binding of p27 with CDK2 and CDK4. Furthermore, the activities of CDK2, CDK4- and CDK6-associated kinase were reduced and the lack of the CDK activity was paralleled by increased hypophosphorylation of Rb protein. Trichostatin also induced apoptosis in all the renal cell carcinoma cell lines. Apoptotic process of ACHN cells was associated with the changes of Bcl-2, caspase-9, caspase-3, caspase-7 proteins as well as mitochondria transmembrane potential (deltapsim) loss. Taken together, these results demonstrate that trichostatin inhibits the growth of renal cell carcinoma cells via cell cycle arrest or apoptosis. 相似文献