The aim of this study was to evaluate the prevalence of peripheral arterial disease (PAD) in Chinese type 2 diabetic patients, and to compare the different risk factors for the low and high ankle-brachial index (ABI). A total of 2040 patients (1001 men and 1039 women) aged 67.0 ± 10.7 years were recruited from 8 university hospitals. PAD was diagnosed by ABI < 0.9 on either leg. Thirty-four possible risk factors were analyzed. Univariate analyses were used to compare the different risk factors between three ABI groups (ABI < 0.9, ABI 0.9-1.3 and ABI > 1.3), and logistic regression analyses were used to identify the independent risk factors. The overall prevalence of PAD was 16.7%. Older age, female gender, history of coronary heart disease (CHD), cerebral infarction (CI), PAD, claudication, longer diabetes mellitus (DM) duration, high blood pressure (HBP), smoking, using diuretics and having a high level of uric acid (UA) were independently associated with low ABI (ABI < 0.9), and male gender and high body mass index (BMI) were associated with high ABI (ABI > 1.3).

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Epigallocatechin gallate (EGCG) is known to impair adhesion of various types of tumor cells to extracellular matrix proteins such as fibronectin and laminin by binding to fibronectin and laminin. However, it is not clear whether the direct binding of EGCG to tumor cells causes a similar impairment. In this study, we examined whether EGCG prevents tumor cells from adhering to fibronectin by binding to a fibronectin receptor, β1 integrin. Human fibrosarcoma HT-1080 cells were incubated with EGCG at various concentrations. After being washed with serum-free cell culture medium, they were plated onto fibronectin-coated wells, and the adhesion activity was examined. The results showed that the pre-treatment with EGCG inhibited cells from adhering to fibronectin in a dose-dependent manner. Cell extracts were then loaded onto an EGCG-immobilized agarose gel column and the bound fractions were examined by enzyme-linked immunoassay and Western blotting using anti-integrin β1 antibody. The results indicated that integrin β1 was bound by the column, demonstrating the interaction between integrin β1 and EGCG. These results suggest that EGCG prevents HT-1080 cells from adhering to fibronectin by impairing interaction between the cells and integrin β1.

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Imatinib is a specific inhibitor of c-KIT that has recently been approved for the treatment of chronic myeloid leukemia and gastrointestinal stromal tumor (GIST). Thapsigargin is an inhibitor of calcium transport to the endoplasmic reticulum (ER) and can inhibit protein maturation. In this study, we evaluated the synergistic cytotoxic effect of thapsigargin and imatinib on the GIST cell line, GIST-T1. Cell viability and cell death were determined by 3,-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry, respectively. In addition, the amount and activation of c-KIT on the cell surface were measured by flow cytometry and western blot analysis, respectively. Thapsigargin alone (for 5 hr incubation) was shown to decrease the amount of c-KIT on the GIST-T1 cell surface and to slightly inhibit the associated tyrosine kinase activity. Interestingly, thapsigargin significantly enhanced the cell death induced by imatinib compared with the effect of imatinib alone. The results further suggested that thapsigargin induced the increased cell death in GIST-T1 cells co-treated with imatinib, at least in part, via disrupting the translocation of c-KIT to the cell surface, and decreasing the activated c-KIT molecules.

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The objective of this study was to investigate L-cysteine influx and efflux in human erythrocytes. L-cysteine is an amino acid required for glutathione synthesis in erythrocytes. In addition to being incorporated into glutathione, the soluble antioxidant L-cysteine plays a role in the maintenance of a proper intracellular or extracellular redox status. Recent investigations have pointed out that L-cysteine may contribute to redox homeostasis in the plasma and in the periplasm of some bacteria. Thus L-cysteine availability in the plasma may influence the oxidized/reduced state of several other metabolites normally found in the plasma. Our L-cysteine uptake studies demonstrated that erythrocytes can respond to an increase in the L-cysteine concentration in the extracellular media and influx L-cysteine in a concentration dependent-manner. The L-cysteine efflux is also time and concentration dependent. Erythrocytes pretreated with higher concentration of L-cysteine displayed higher efflux rates. Erythrocytes pretreated with L-cysteine 1 mM displayed efflux and increased the free-SH concentrations up to 0.184 ± 0.010 mM in the incubation media in 1 hr. While this concentration reached 0.843 ± 0.012 mM in 10 mM-L-cysteine pretreated erythrocytes. Our results also showed that the L-cysteine efflux is partly mediated by the Alanine-Serine-Cysteine (ASC) system. The presence of alanine or serine in the incubation media decreased the rate of efflux by about 16%. Our results also showed that the L-cysteine efflux process is not a simple diffusion but a carrier-mediated process. When compared with N-acetyl-L-cysteine (NAC), which is known to diffuse through the membranes, L-cysteine displayed a higher efflux rate under the same conditions. Pretreatment of erythrocytes with L-cysteine 4 mM increased the free-SH concentration to 0.48 ± 0.005 mM whereas the same concentration of NAC brought the free-SH concentration to 0.36 ± 0.01 mM in the incubation media. Our results suggest that erythrocytes may contribute to redox and metabolite homeostasis of the plasma.

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Estrogens that originate from humans and animals are thought of as a factor of endocrine disruptors in the environment. We investigated their halogenated derivatives, which could be produced by chlorine treatment at a sewage treatment plant. The chlorinated derivatives of estrone (E1), 17β-estradiol (E2), estriol (E3), and 17α-ethynylestradiol (EE2) were produced by the reaction with hypochlorous acid in organic solvents and also brominated derivatives when bromide ions were present. The structures of chlorinated and brominated estrogens isolated were determined by MS and NMR spectroscopy. The estrogenic activities of the halogenated derivatives were measured by yeast two-hybrid assays incorporating the human estrogen receptor α (hERα) or medaka fish (Oryzias latipes) estrogen receptor α (medERα). Although the activities of 4-chloroestrone (4-ClE1) and 10-chloro-1,4-estradiene-3,17-dione were similar to those of E1, the activities of 2-ClE1 and 2,4-dichloroestrone (2,4-diClE1) were approximately 4/5 and 1/50 that of E1, respectively, in an agonist assay for hERα. No activity was detected in 2,4,16,16-tetrachloroestrone (2,4,16,16-tetraClE1). The estrogenicities of chlorinated derivatives of E2, E3, and EE2 showed a similar tendency to that of E1. The brominated derivatives showed slightly weaker activity than the corresponding chlorinated derivatives. However, many estrogens halogenated at the 2 and 4 positions still had activity that was approximately 10³-10⁴ times stronger than that of bisphenol A.

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Various branched isomers of 4-nonylphenol (NP) and, in addition, the other 4-alkylphenols (APs) were synthesized and their estrogenic activities were assessed using the yeast two-hybrid system. We investigated the relationships between the structure of the nonyl group of NP isomers and their estrogenic activities based on the following five factors: the length of the main alkyl chain, the degree of branching on the α-carbon, the degree of bulkiness, the position of the branch, and the cyclic structure in the nonyl group. An appropriate length of the main alkyl chain was essential for the estrogenic activity. A small effect of the branching on the α-carbon was observed. The importance of the bulkiness and position of the branch in the nonyl group was suggested from the results of the synthesized NP isomers possessing the high estrogenic activities. The bulkiness on the β-carbon was the most important factor for the high estrogenic activity. The investigation of the cyclic structure also indicated the significance of the bulkiness around the β-carbon. The bulkiness on the γ-carbon was also suggested to be an important factor. The metabolic effect of the synthesized APs on the estrogenic activity was also examined using a liver S9. The estrogenic activities of the selected APs were either reduced or lost. In addition, GC-MS analyses of the commercial NP and synthesized NP isomers revealed that the nine synthesized NP isomers were included in the commercial NP.

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The present study was designed to investigate the in vivo effects of nickel chloride [NiCl₂; 8, and 16 mg/kg body weight (b wt)] and/or Potassium dichromate (K₂Cr₂O₇; 5 and 10 mg/kg b wt) in the liver of adult mice. The beneficial effects of vitamin E (2 mg/kg) along with their combination were also studied. The antioxidative indices including oxidative lipid peroxidation (LPO) and antioxidative enzymes such as glutathione (GSH), total sulfhydryl (-SH) groups, total ascorbic acid (TAA), superoxide dismutase (SOD) and catalase (CAT) were evaluated in the hepatic tissue using well established techniques. Nickel and/or chromium treatments to mice revealed a significant decline in the levels of these antioxidant parameters as compared to control. Concomitantly a significant increase in lipid peroxidation was obtained. These data indicated that the treatment induced oxidative stress in the hepatic tissue of treated mice, which was more pronounced by combination of metal salts. But supplementation of vitamin E with NiCl₂ + K₂Cr₂O₇ to mice exerted no significant alterations in the liver antioxidant system as compared to control, thus indicating its ameliorative role. These findings suggest that vitamin E prevents LPO and protects the antioxidant system in the mouse liver.

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Luminescent and light absorption umu tests were used to investigate the genotoxicity of microbial volatile organic compounds (MVOCs), which have been reported to occur in conjunction with the growth of filamentous fungi. Investigation of 20 types of MVOC samples confirmed the SOS-inducing activity of 1-octen-3-ol, 2-methyl-1-propanol, 2-heptanone, 3-octanol, 1-pentanol, 1-butanol, 2-methyl-1-butanol, 3-methyl-1-butanol, 3-methyl-2-butanol, 3-octanone, 2-hexanone, 2-butanone, 3-methyl-2-butanone, 2-pentanol, ethyl isobutyrate, and terpinen-4-ol. Of these materials, 3-methyl-2-butanone and 3-methyl-2-butanol, which were positive in both the luminescent and light absorption umu tests, were clearly shown also to be mutagenic based on the results of the Ames test. Each of these 20 MVOCs is known to be produced by microorganisms commonly detected in indoor environments, and long-term exposure could be a health hazard.

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The effect of ethanolic extracts of Punica granatum (P. granatum) and Quercus infectoria (Q. infectoria) on cell surface hydrophobicity of 10 clinically isolated Helicobacter pylori strains were investigated using salt aggregation test. Both P. granatum and Q. infectoria significantly increased the hydrophobicity of all isolates, irrespective of their antibiotic resistance patterns. These two plant species were demonstrated to produce both bacteriostatic and bactericidal activities. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values were from 0.78 to 6.25 and 3.12 to 6.25 mg/ml for P. granatum, and from 3.12 to 6.25 and 3.12 to 12.5 mg/ml for Q. infectoria, respectively. Ethyl acetate and n-butanol fractions of both plants had values at least 10-fold lower than the MIC and MBC values of the ethanolic extracts. The results indicate no relationship of the increased cell-surface hydrophobicity with the MIC or MBC values.

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This investigation attempts to clarify the effects of the plastic monomer bisphenol A (BPA) and related chemicals on 3,3′,5-triiodothyronine (T₃)-induced and spontaneous anuran tadpole tail regression. T₃-induced tail regression was found to be suppressed by BPA and tetrabromobisphenol A (TBBPA), tetrachlorobisphenol A (TCBPA), and tetramethylbisphenol A (TMBPA). T₃-treated Rana rugosa tadpole tails displayed marked apoptotic features, including DNA fragmentation and ladder-like profiles, as opposed to essentially little or no fragmentation and ladder formation for BPA, TBBPA, TCBPA and TMBPA-treated tails. BPA and related compounds also inhibited Silurana tropicalis spontaneous metamorphosis controlled by endogenous circulating thyroid hormone (TH). These results indicate that BPA and related compounds are TH antagonists. In transgenic Xenopus laevis tadpoles carrying plasmid DNA containing TH response element (TRE) and 5′-upstream promoter region of the TH receptor (TR) bA1 gene linked to a green fluorescent protein (EGFP) gene, T₃ induced a strong EGFP expression in the hind limbs, while T₃ plus BPA, TBBPA, TCBPA or TMBPA suppressed the expression, suggesting BPA and related chemicals all act in preventing the binding of T₃ to TR, resulting in inhibition of TR-mediated gene expression.

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The antioxidant activity of the crude extract prepared from oregano (Origanum vulgare L.) and its antiinflammatory activities in mouse models of stress-induced gastritis and contact hypersensitivity were investigated. Oregano extract was a substrate for peroxidase, similar to phenol. Oregano extract exhibited iron-reducing activity, although its strength was approximately one-fifth of that of ascorbic acid. Oral administration of oregano extract significantly prevented mouse gastritis induced by cold-restraint stress. Percutaneous administration of oregano extract also significantly prevented mouse contact hypersensitivity induced by oxazolone. These antiinflammatory activities of oregano extract tended to be weaker than those of hydrocortisone. The antioxidant activities of oregano extract appear to contribute to its preventive effects against inflammatory diseases, such as stress-induced gastritis and contact hypersensitivity in mice.

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The effects of L-methionine (Met) on tissue distribution of methylmercury (MeHg) in mice were investigated and compared to those of other amino acids and amino acid analogues to determine whether Met could play special roles in distribution of MeHg. Three hr after the injection with MeHg-L-cysteine (Cys) (10 μmol/kg each), brain Hg concentration was suppressed by a co-injection with Met, L-phenylalanine (Phe), L-leucine (Leu) or 2-amino-2-norbornane-carboxylic acid (BCH), although the concentration was not affected by that with L-serine, α-aminoisobutyric acid or α-(methylamino)isobutyric acid. Hg concentration in liver was enhanced but that in the kidney was suppressed only by the co-injection with Met. Hg concentrations in blood and plasma were suppressed only by Met at least within 2 hr, but these differences disappeared at 3 hr. These results suggest that Met plays important and special roles in tissue distribution of MeHg in mice, at least in the liver and kidney, although MeHg distribution in the brain is similarly affected by not only Met but also other compounds such as Phe, Leu and BCH.

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The goal of this research was to assess the performance of serum creatine kinase (CK), creatine kinase MB (CKMB) [mass and activity], troponin I (TnI) and troponin T (TnT) in the diagnosis of acute myocardial infarction in patients admitted to the Coronary Care Unit at Queen Alia Heart Institute, Amman, Jordan, between March and July 2001. Blood samples collected for cardiac enzyme determination (CK, CKMB activity) were stored at -20°C for later determination of CKMB mass [Abbott Axsym, Ortho Clinical Diagnostics (OCD) ECi and Roche Elecsys], TnI (Abbott Axsym) and TnT (Roche Elecsys). The relative index (RI = CKMB mass/CK), for CKMB mass measurements, was calculated. Clinical notes and/or discharge diagnosis for each patient were reviewed to obtain the diagnosis of acute myocardial infarction. Fifty samples were from acute myocardial infarction (AMI) patients. Area under Receiver Operating Curve values were: CK 0.56, CKMB activity 0.72, percentage of CKMB activity 0.73, CKMB mass (Abbott) 0.76, CKMB mass (Roche) 0.77, CKMB mass (OCD) 0.78, RI (Roche) 0.83, RI (Abbott) 0.87, RI (OCD) 0.86, TnI 0.95, TnT 0.94. Sensitivity: TnI 88%, TnT 93%; specificity TnI 99%, TnT 99%. There was no significant difference in performance between TnI and TnT assays or between any of the CKMB mass measurements. Present results show that TnI and TnT are better cardiac markers than CK and CKMB, mass or activity.

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Phytoestrogens containing isoflavonoids are thought to exhibit preventative effects on estrogen-responsive diseases. Chemical modifications, such as prenylation, in biosynthetic processes enhance the structural variety of isoflavonoids and prompted us to carry out a structure-activity relationship study. We determined the estrogenic/anti-estrogenic activities and estrogen receptor (ER)-binding affinities of eight kinds of prenylated isoflavones isolated from Millettia pachycarpa (Leguminosae), and those of two kinds of non-prenylated compounds (genistein and daidzein). By comparing these compounds, the pharmacophores for estrogenic/anti-estrogenic activities were elucidated. None of the tested compounds (except genistein) were estrogenic on ligand-dependent yeast-two hybrid assay. On the other hand, 5 isoflavones showed distinct anti-estrogenic activity. Unexpectedly, the most potent antagonists, isoerysenegalensein E and 6,8-diprenylorobol, showed anti-estrogenic activity comparable to that of 4-hydroxytamoxifen, a typical ER antagonist. This suggests that genistein became an antagonist after prenylation and hydroxylation. The pharmacophores providing genistein with strong anti-estrogenic activity were as follows: prenyl groups of the 6- and 8-positions on the A-ring, hydroxyl group of the 6-prenyl moiety or the B-ring (catechol form), non-cyclization of the prenyl group with the A-ring, and non-hydroxylation of the 8-prenyl group on the A-ring. The ER-binding affinities of the isoflavonoids were not sufficiently high to explain their potent antagonistic activities, thus suggesting 17β-estradiol-non-competitive mechanisms.

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Objectives: To evaluate the observed cisplatin (CDDP) nephrotoxicity in adult cancer inpatients by using Clinical Data Warehouse (CDW). Methods: A historical cohort study was conducted in Osaka University Hospital. Adult cancer inpatients (2000/1/1-2004/12/31) whose sCr level on admission < 1.2 mg/dl were divided into three groups based on the exposure of CDDP, non-exposure of CDDP but with (Non-CDDP group) or without (Control group) other anticancer agents. Patients whose sCr ≥ 1.2 mg/dl at least once during hospitalization were considered as those having the occurrence of the nephrotoxicity and their sCr < 1.2 mg/dl on discharge as having recovered from the nephrotoxicity. After matching patients' characteristics through stratification and randomization, the rates of nephrotoxicity and the rates of recovery among the three groups were compared. Logistic regression was performed to investigate the CDDP doses — nephrotoxicity associations. Results: The rate of observed nephrotoxicity was 28.0% (127/454) in the CDDP group, 19.6% (89/454) in the Non-CDDP group and 19.4% (88/454) in the Control group, respectively (p = 0.002). The risk ratio (RR) was 1.43 (95%CI: 1.13-1.81), 1.44 (95%CI: 1.14-1.83) and 1.01 (95%CI: 0.78-1.41) between CDDP vs. Non-CDDP, CDDP vs. the control and Non-CDDP vs. the Control group. The recovery rate was 69.3% (88/127), 61.8% (55/89) and 69.3% (61/88) in the three groups, respectively (p = 0.903). The observed CDDP nephrotoxicity was dose associated (p = 0.037) but not total accumulated doses associated (p = 0.144). Conclusions: CDDP is a risk factor to the observed nephrotoxicity in our adult cancer inpatients. The observed nephrotoxicity was CDDP dose related and is considered to be reversible.

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