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Hepatocellular carcinoma (HCC) is one of the major malignancies worldwide and is associated with poor prognosis due to the high incidences of metastasis and tumor recurrence. Our previous study showed that overexpression of p21-activated protein kinase 1 (PAK1) is frequently observed in HCC and is associated with a more aggressive tumor behavior, suggesting that PAK1 is a potential therapeutic target in HCC. In the current study, an allosteric small molecule PAK1 inhibitor, IPA-3, was evaluated for the potential in suppressing hepatocarcinogenesis. Consistent with other reports, inhibition of PAK1 activity was observed in several human HCC cell lines treated with various dosages of IPA-3. Using cell proliferation, colony formation and BrdU incorporation assays, we demonstrated that IPA-3 treatment significantly inhibited the growth of HCC cells. The mechanisms through which IPA-3 treatment suppresses HCC cell growth are enhancement of apoptosis and blockage of activation of NF-κB. Furthermore, our data suggested that IPA-3 not only inhibits the HCC cell growth, but also suppresses the metastatic potential of HCC cells. Nude mouse xenograft assay demonstrated that IPA-3 treatment significantly reduced the tumor growth rate and decreased tumor volume, indicating that IPA-3 can suppress the in vivo tumor growth of HCC cells. Taken together, our demonstration of the potential preclinical efficacy of IPA-3 in HCC provides the rationale for cancer therapy.  相似文献   
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A separation and detection scheme is presented for the determination of free, esterified and total cholesterol in human serum. Separation is accomplished by reversed-phase high-performance liquid chromatography and the eluate is monitored by the laser-based optical activity detector. The method is simple, accurate and has the advantage of specificity and selectivity when compared with the many methods commonly used.  相似文献   
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We conducted a multicenter evaluation of the analytical and clinical performance of the automated Bayer Immuno 1 complexed PSA (cPSA) assay, and compared assay performance to the Bayer Immuno 1 PSA assay. We sought to determine whether measurements of cPSA could be of clinical utility in the management of patients with prostate cancer. Results of the 10-day imprecision across three evaluation sites produced total CV < 2.50% and an analytical sensitivity of 0.02 microgram/L. There was an increased trend in clinical sensitivity for prostate cancer with increasing stage of disease (71-86%). Clinical specificity for patients with benign urogenital disease was 74.8%, and for other nonprostate diseases ranged from 91.1-100%. Retrospective serial monitoring of 155 patients with prostate cancer demonstrated concordance of cPSA measurements to clinical status for 97% of the patients analyzed. Results from the clinical studies using the Bayer Immuno 1 cPSA assay were comparable to results obtained with the Bayer Immuno 1 PSA assay. The Bayer Immuno 1 cPSA assay demonstrates analytical performance and clinical effectiveness in the management of prostate cancer patients during the course of disease and therapy.  相似文献   
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An automated DNA synthesis protocol (FC3) has been optimized to decrease the cost of chemical consumption by two- to threefold. Anion-exchange chromatography at pH 12.5 in a Mono Q (Pharmacia) column was used to analyze the oligonucleotides we synthesized. From these analyses, we formulated the FC3 program and a procedure by which a DNA synthesizer designer or operator can use 18-base-long homopolymers of A, G, C, and T to optimize the reaction times, reagent concentrations, solvent wash conditions, and the many steps in the synthesis cycle.  相似文献   
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Severe adverse reactions to propylthiouracil occur in 1-5% of patients. Three major side effects, namely agranulocytosis, hepatotoxicity and drug-induced hypersensitivity, have been described though these syndromes are not distinct entities and there can be overlaps in the clinical manifestations. The drug-induced hypersensitivity may be an immune-mediated reaction with multiorgan involvement in which a combination of polyarthritis, cutaneous vasculitis and fever is common. We report a patient with propylthiouracil-induced hypersensitivity with an unusual combination of high spiking fever, migratory polyarthritis, reversible sensorineural deafness, normochromic normocytic anaemia, leucocytosis and hepatotoxicity associated with polyclonal activation of multiple autoantibodies. This case illustrates the highly variable clinical manifestations of the syndrome. The prompt recovery upon withdrawal of the drug indicates the importance of early diagnosis.  相似文献   
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Changes in the structural organization of the funiculus of Phaseolusvulgaris were correlated with mitochondrial respiration rates,including both cytochrome and alternative pathway activitiesand seed weight during development of the seed. After fertilization,vascular elements are still differentiating within the funiculus.The central core of the funiculus consists mainly of procambialcells together with a few mature xylem and phloem elements.As the seed gradually matures, more vascular elements beginto appear. Procambial cells in the upper region of the funiculusadjacent to the pod differentiate and result in xylem and phloemappearing as a convoluted, intertwining network of strands.In the lower part of the funiculus adjacent to the seed, fewervascular elements are present and they organize into a smallbundle prior to entering the seed. The funiculus is fully developedat the cotyledon stage judging from the size of the funiculusand the organization of the vascular tissues. At the early maturationstage, the seed begins to enlarge in both size and weight. Correlatedwith development of the funiculus tissue is a gradual decreasein total rates of respiration. Inhibitor studies using potassiumcyanide and/or salicylhydroxamic acid show that the CN-insensitive,or alternative pathway is the predominant route of electrontransport in funiculus mitochondria during the early stagesof development. This pathway declines in activity with age whereuponcytochrome pathway activity accounts for all of the respirationby the time vascular tissues are mature and the seed is rapidlyexpanding.Copyright 1994, 1999 Academic Press Funiculus, vascular tissue, cytochrome, respiratory pathway, alternative respiratory pathway, Phaseolus vulgaris  相似文献   
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