Measurements of ambulatory blood pressure (ABP) and of home blood pressure (HBP) as an adjunct to casual/clinic BP (CBP) measurements are currently widely used for the diagnosis and treatment of hypertension. We have monitored a rural cohort of people from the population of Ohasama, Japan, with respect to their prognosis and have previously reported that ABP and HBP are superior to CBP for the prediction of cardiovascular mortality. We examined the prognostic significance of white-coat hypertension for mortality and found that the relative hazard for the overall mortality of patients with white-coat hypertension was significantly lower than that for true hypertension during 5-year observation period but observed that the development of sustained hypertension was more frequent in patients with white-coat hypertension than those with true normotension during 10-year observation period. Our results also confirmed that day-by-day variability as well as short-term blood pressure variability (as measured every 30 min) was independently associated with cardiovascular mortality. In addition, research has recently focused on isolated systolic hypertension and pulse pressure as independent risk factors for poor cardiovascular prognosis. The Ohasama study also clearly demonstrated that isolated systolic hypertension and increased pulse pressure, as assessed by HBP, were associated with an increase in the risk of cardiovascular mortality. Concerning diurnal blood pressure variation, the relative hazard for cardiovascular mortality increased in non-dippers and inverted dippers while that in extreme dipper did not. The Ohasama study also clearly demonstrated that nocturnal BP levels in hypertensive patients with extreme dipper were significantly higher than those in normotensive subjects. The Ohasama study showed that the level and variability of hypertension as assessed by ABP and HBP are independent predictors of cardiovascular morbidity and mortality. It also demonstrated an independent association between the prognosis of hypertension and each component of ABP and HBP, indicating the prognostic significance of these blood pressure measurements.
Methylmercury (MeHg) is an environmental pollutant with neurotoxic effects on the central nervous system. The major exposure route of MeHg to humans is via consumption of fish and shellfish which accumulate the chemical through the food web in an aquatic environment. We have been conducting a survey on hair mercury contents among general populations from different districts to estimate the current Japanese MeHg exposure level. In Japan, a provisional regulatory standard of mercury and MeHg in fish and shellfish was determined in 1973 based on the assumption of a safe intake limit of 0.17 mg/person/week (0.48 μg/kg/day). On the other hand, the US EPA issued a revised reference dose based on a cohort study conducted in the Faroe Islands. Recently, a provisional tolerable weekly intake (PTWI) of MeHg was revised to 1.6 μg/kg/week in 61st Joint FAO/WHO Expert Committee on Food Additives (JECFA), which was about half that of the Japanese standard. The distribution of hair mercury levels in Japanese populations currently obtained from 10 districts indicated that 25% of the Japanese females of child-bearing age were estimated to be exposed to MeHg over the PTWI level. This would reflect the high Japanese consumption of marine products. Not only mercury contamination, but also the nutritional benefit may have to be considered when discussing the risk involved in the current level of fish and shellfish consumption in Japan.
The CheckLite™ 250 Plus portable bioluminescence assay system for measuring bacterial adenosine 5'-triphosphate (ATP) was investigated for its performance with respect to the field detection of bacteria in bioterrorism incidents. Vegetative bacteria, Escherichia coli (E. coli), Bacillus subtilis (B. subtilis), Staphylococcus aureus, and Yersinia pseudotuberculosis gave considerably high luminescence in a dose-dependent manner with responses of 104-105 relative light units (RLU) per 107 cells, whereas spore forms of B. subtilis showed considerably low luminescence with 214 RLU per 109 spores. Typical white powder materials such as wheat flour, sugar, and bovine serum albumin at concentrations of 0.1 and 0.5% (w/v) gave only negligible luminescence (lower than 400 RLU), and did not change the luminescence of E. coli cells significantly (42-102% of the control). The luminescence of B. subtilis spores increased considerably to over 104 RLU per 107 spores by pretreatment consisting of 37°C incubation for 30 min in nutrient broth medium containing 4 mM L-alanine. The increased luminescence by this pretreatment was not changed considerably (42-145% of the control) in the presence of the above tested white powder materials (0.1 and 0.5%).
Vasodilatory compounds in the weak acidic fraction of a benzene extract of diesel exhaust particles (DEP) were fractionated by column chromatography through silica gel, and the chemical structures of these compounds were analyzed using GC-MS and 1H-NMR. The compounds in DEP that cause vasodilation — 3- and 4-nitrophenol, 2-methyl-4-nitrophenol, 3-methy-4-nitrophenol, and 4-nitro-3-phenylphenol — were isolated and identified. All five of these nitrophenols had vasodilatory activities (10-4 to 10-6 M) in rat thoracic artery assays, and 4-nitro-3-phenylphenol was the most potent vasodilator among these compounds. In addition, nine other alkylnitrophenols were isolated from the benzene extract of DEP and characterized.
In the Japanese Food Sanitation Law, the water content or loss on drying (LOD) value of standard materials for pesticide residue analysis is not officially designated. In the present study, to investigate the actual situation of the water content or LOD value of commercial pesticide standards, 40 pesticide standards were determined by the Karl-Fisher aquametry (KF) and 24 pesticide standards were done by a thermogravimetric analysis (TGA). Furthermore, the applicability of KF and TGA was also discussed. The water content or LOD values of most pesticides were within 1%, therefore they are regarded as having the negligible values within the limit of error for the residual pesticide analysis. However, since some pesticides, dichloropropionic acid sodium salt, sodium dimethyl dithiocarbamate, paraquat, diquat dibromide, formamidine hydrochloride, maneb, iminoctadine triacetate, mancozeb and monocrotophos, had relatively large amounts of water or LOD values, the water content and LOD value of such pesticides should be carefully considered during the pesticide residue analysis. For comparison of KF and TGA, there are differences in both the data for some pesticide standards. The reason seems that the pesticides interfere with the KF redox reaction.
The removal efficiency of NH3, (CH3)NH2, (CH3)2NH and (CH3)3N into woody charcoal carbonized at 500°C and activated carbon was determined by the attenuation of their concentrations in the 5 l bags at cool (5°C) and room temperature (20°C). A discussion follows on the deodorization performance against four gases with attention to the physical and chemical characteristics of adsorbent surfaces. It was found that the high acidity of woody charcoal surface was more suitable for the adsorption of NH3 and (CH3)NH2 gases than the activated carbon under both temperatures, and the activated carbon having larger micro, meso pore volumes following an increase in specific surface area showed higher capacity for (CH3)3N gas adsorption than the woody charcoal. Also the activated carbon is more suitable for (CH3)2NH gas adsorption than the woody charcoal at 5°C, but its removal efficiency using the activated carbon is lower than the woody charcoal at 20°C. Much acidic functional groups on the adsorbent has high adsorption potential just like chemical adsorption is necessary to enhancement of (CH3)2NH gas at 20°C.
The growth rate of metallothionein (MT)-null (MT-/-) cells was significantly lower than that of wild-type (MT+/+) cells, the cell cycle being arrested at the G2/M phase in MT-/- cells and endogenous reactive oxygen species (ROS) accumulating with the progress of the cell cycle. Exogenous ROS generated on treatment with H2O2 arrested the cell cycle of MT-/- cells at the G2/M phase more severely than that of MT+/+ cells. These observations suggest that MT maintains the normal cell cycle as an antioxidant against excessive endogenous ROS that are generated synchronously with the cell cycle and disturb the normal cell cycle.
Radiolabeled antibody has attractive features as a therapeutic agent or diagnostic reagent. However, it is difficult for radiolabeled antibody to enter the central nervous system (CNS). The purpose of this study was to develop a method of delivering radiolabeled single-chain Fv (scFv) antibody into the CNS with the transactivator of transcription (TAT), one of the protein transduction domains. Oligonucleotide encoding TAT was linked to the 5′-terminal of the scFv gene. The construct was subcloned into the pET-23b vector, and the recombinant protein was expressed as an inclusion body in Escherichia coli. After solubilization and purification, the recombinant protein was oxidatively labeled with 125I, and the radiolabeled recombinant protein was injected intraperitoneally into mice. Six hours later the brains were collected and homogenized, and the protein fractions were prepared by acetone precipitation. The radioactivity in the cerebrum was about 1.6-fold higher in mice administered TAT-scFv than in those administered scFv alone. The radiolabeled TAT-scFv antibody was delivered into the cerebrum more efficiently than radiolabeled scFv antibody without TAT, suggesting that TAT peptide could be a candidate tool for delivering radiolabeled scFv antibody into the CNS.
A biological specimen, urine, was prepared by the most simple sample preparation method, direct dilution, and determination of seven elements in the urine samples, Fe, Cu, Zn, Se, As, Cd, and Pb, was investigated by inductively coupled plasma mass spectrometry (ICP-MS). In addition, acid-decomposed samples were similarly investigated. Regarding the matrix effect of concomitant components, as the sodium hydrochloride concentration increased, the observed ion intensity of the measured element linearly decreased. Matrix interference by sodium hydrochloride could be fairly corrected by addition of internal standard elements excluding determination of Fe and Zn. On comparison of the measured values of samples prepared by direct dilution and acid-decomposition samples, the values were slightly lower in the samples prepared by direct dilution for many elements. For Zn and As, the analytical results of the human urine standard reference material were well consistent with the certified values.
Plasma vitellogenin (VTG) assay was developed using ovariectomized goldfish (Carassius auratus) for determining the estrogenic effects of endocrine-disrupting chemicals. In a laboratory study, we assessed the estrogenic activity of commercial fish diets by using a diet for ornamental carp (CD) and a casein-based formulated fish diet (FD), which was shown to not contain soybean or fish meal in a previous study. In ovariectomized fish, plasma VTG concentrations were significantly higher in the CD-fed group than in the FD-fed group. These results indicate that the estrogen activity of CD may be high enough to cause induction of plasma VTG in ovariectomized goldfish as previously observed in male goldfish. Moreover, the effect of estrogen on plasma VTG induction was confirmed by significant plasma VTG production following the exposure of FD-fed ovariectomized goldfish to a nominal estradiol-17β concentration of 100 μg/l for 31 days. Our data suggest that induction of plasma VTG using ovariectomized goldfish is a good tool for evaluating the estrogenic effects of endocrine-disrupting chemicals.
Diesel exhaust (DE) is a serious air pollution problem in big cities. Most suspended particulate matter (SPM) less than 2.5 μm in diameter consists of diesel exhaust particles (DEPs), which are reported to cause pulmonary carcinogenesis, allergic rhinitis, and bronchial asthma-like diseases. It has been recently reported that DE also affects the circulatory and reproductive systems. Yoshida et al. reported that mRNA expression of steroidogenic factor-1 (Ad4BP/SF-1) and of Müllerian inhibitory substance (MIS), which are essential for male gonadal differentiation, decreased significantly in male fetuses when maternal mice were exposed to DE at levels of 0.1 or 3.0 mg DEP/m3 for 8 hr per day between 2 and 13 days postcoitum (dpc). In this study, maternal mice were exposed to DE 0.1 mg DEP /m3 for 8 hr per day between 2 and 13 dpc. Expression levels of Ad4BP/SF-1 and MIS mRNA in female fetuses were not decreased. However, expression levels of bone morphogenetic protein-15, reported to be related to development of the oocyte, were significantly decreased in comparison with that in the control group. Our data suggest that female fetuses of pregnant mice exposed to DE in utero are less sensitive to the expression levels of mRNAs for Ad4BP/SF-1 and MIS compared with males and that DE may affect development of the oocyte in the female fetus.
Urban air particulate samples were collected on a quartz fiber filter with a High Volume Air Sampler, which was placed on the roof of the National Institute of Public Health, Minato-ku, Tokyo. Those samples were tested in both transformation assay using Bhas42 cells (Bhas assay) as a bioassay for cancer promoters and in the Ames microsuspension method as for initiators. Good dose-response relations were observed with both testing methods, and the samples showed mutagenicity and promoter activity. A comparison per particle weight between the samples collected in spring and autumn indicated that the value was higher in autumn samples, suggesting that mutagenic substances and cancer promoters might be polluting the air and be correlated with each other. Therefore, to monitor the carcinogenic-related activity of air pollutants, not only the mutagenicity assay but also bioassays for cancer promoters are required.
Particle size adjusting equipment was manufactured to determine the deposition ratio of airborne particles in the respiratory tract. This equipment is composed of an Andersen low-pressure impactor, one 100 l stainless steel tank, two filter holders, one Tedlar bag, one flow meter, and two pumps. We measured deposition ratios of benzo[a]pyrene (BaP) in size-fractionated particles in the respiratory tract using this equipment together with a Hans-Rudolph mask. BaP in particles was extracted using the sonication method and measured with the column concentration HPLC/spectrofluorometric detection method. BaP concentrations in PM0.52 (particles smaller than 0.52 μm) ranged from 0.025 to 0.193 ng/m3 (CV: 72%), and the CV of deposition ratios of BaP was 23%, (average 44.5%). Furthermore, we measured the deposition ratios of BaP in 6 different sized particles. While high deposition ratios of BaP were observed in PM3.9 air, PM2.5 air, and PM0.76 air, low deposition ratios were found in PM0.52 air, PM0.33 air, and PM0.13 air. We obtained similar results to the theoretical deposition ratio calculated from lung models.
We examined the effect of herbal teas (including black and green teas) on conjugation reactions within a human colon carcinoma cell line, Caco-2. After adding herbal tea to the culture medium of Caco-2 cells, accumulation of 1-naphthyl sulfate and glucuronide was determined within the medium by analytical HPLC prior to 24 hr. A reduction in sulfoconjugation (< 50% of the control value) was observed in cells treated with 5% solutions of green tea, jasmine tea or black tea. Mild induction of sulfoconjugation (20–30%) was detected in cells exposed to 5% solutions of hibiscus or lemongrass tea. In addition, a slight reduction (20–30%) in glucuronic acid conjugation (glucuronidation) was observed in cells treated with rose red, peppermint, lavender or St. JohnÕs wort. At low concentrations, ranging from 0.1–1.0%, several herbal teas resulted in weak but significant induction (10–20%) of both types of conjugation reactions. These results suggest that herbal teas modify conjugation reactions within intestinal epithelial cells, thereby potentially affecting the bioavailability and toxicity of therapeutic drugs and environmental chemicals.
A geniposide overlay method for the detection of genipin/geniposide-binding proteins was attempted using a specific anti-geniposide antiserum. The specific anti-geniposide antiserum that recognized the genipin moiety was obtained from rabbits immunized with geniposide-rabbit serum albumin (RSA) conjugate as antigen. The results of the overlay method revealed a major geniposide binding protein with a molecular weight about 170 kDa in the cytosolic fraction of rat brain cortex and PC12h cells. The major protein band was comparable with the protein band (about 170 kDa) detected by simultaneous Western blot analysis using anti-neuronal nitric oxide synthase (nNOS) antiserum. Furthermore, geniposide activated NOS activity in a concentration-dependent manner. These results indicate that the antiserum obtained was useful for the detection of a genipin/geniposide-target molecule and strongly suggested that direct binding to and activating of nNOS cause the neuritogenic activity of genipin/geniposide in PC12h cells.