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21.
Kurauchi K Nakaguchi Y Tsutsumi M Hori H Kurihara R Hashimoto S Ohnuma R Yamamoto Y Matsuoka S Kawai S Hirata T Kinoshita M 《Environmental science & technology》2005,39(8):2762-2768
Detection of endocrine disrupting chemicals, in particular, environmental estrogens with living organisms, has many advantages if compared to chemical analysis. The screening of novel pollutants with meaningful endpoints, the integration of uptake, bioconcentration, and excretion as well as the evaluation of endocrine disrupting effects with respect to toxicity require in vivo biotests for estrogen-like substances (ELSs). Critical disadvantages of whole organism biotests are their low sensitivity and the need for laborious and time-consuming work. To overcome these problems, we have developed a transgenic medaka strain harboring the green fluorescence protein (GFP) gene driven by choriogenin H gene regulatory elements. Choriogenin H is an egg envelope protein induced by estrogens in the liver. With yolk sac larvae of this strain, GFP induction in liver was observed 24 h after onset of aqueous exposure to 0.63 nM 17beta-estradiol (E2), 0.34 nM ethynylestradiol, or 14.8 nM estrone. Furthermore, concentrated sewage treatment effluent induced GFP expression. Comparison of E2 equivalents estimated by GFP-induction in transgenic medaka, a YES assay, and GC/MS showed detection limits in the same order of magnitude. These results indicated that the sensitivity of the transgenic medaka strain was sufficient for application as an alternative model in monitoring environmental water samples for ELSs. 相似文献
22.
Tsuji S Nakanoi M Terada H Tamura Y Tonogai Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2005,46(3):63-71
Identification and determination of butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), nordihydroguaiaretic acid (NDGA), propyl gallate (PG) and tert-butylhydroquinone (TBHQ) by means of LC/MS and GC/MS were examined. These five phenolic antioxidants were detected as their pseudo-molecular ions [M-H]- by LC/MS using a Shim-pack FC-ODS column with drying gas. Moreover, BHA, BHT and TBHQ were detected based on their mass fragment ions by GC/MS. Decomposition of TBHQ, NDGA and PG during analysis could be prevented by the addition of L-ascorbic acid (AsA) to the extraction solvent. All five antioxidants were extracted from nikuman, olive oils, peanut butter, pasta sauce and chewing gum with a mixture of acetonitrile-2-propanol-ethanol (2:1:1) containing 0.1% AsA (AsA mixture), which had been cooled in a freezer and filtered. One part filtrate and 5 parts water were mixed and placed on a Mega-Bond Elut C18 cartridge, except in the case of chewing gum. Lipids in foods were removed on a C18 cartridge by washing with 5 mL of 5% acetic acid, and antioxidants were eluted with 5 mL of AsA mixture. The antioxidants spiked into nikuman, olive oil, peanut butter, pasta sauce and chewing gum were successfully identified and their concentrations determined by LC/MS, and GC/MS with good recoveries. 相似文献
23.
Masahiro Hatasa Sumiko Yoshida Hirokazu Takahashi Kenichi Tanaka Yoshihito Kubotsu Yujin Ohsugi Takaharu Katagiri Takanori Iwata Sayaka Katagiri 《International journal of molecular sciences》2021,22(7)
Periodontal disease is an inflammatory disease caused by pathogenic oral microorganisms that leads to the destruction of alveolar bone and connective tissues around the teeth. Although many studies have shown that periodontal disease is a risk factor for systemic diseases, such as type 2 diabetes and cardiovascular diseases, the relationship between nonalcoholic fatty liver disease (NAFLD) and periodontal disease has not yet been clarified. Thus, the purpose of this review was to reveal the relationship between NAFLD and periodontal disease based on epidemiological studies, basic research, and immunology. Many cross-sectional and prospective epidemiological studies have indicated that periodontal disease is a risk factor for NAFLD. An in vivo animal model revealed that infection with periodontopathic bacteria accelerates the progression of NAFLD accompanied by enhanced steatosis. Moreover, the detection of periodontopathic bacteria in the liver may demonstrate that the bacteria have a direct impact on NAFLD. Furthermore, Porphyromonas gingivalis lipopolysaccharide induces inflammation and accumulation of intracellular lipids in hepatocytes. Th17 may be a key molecule for explaining the relationship between periodontal disease and NAFLD. In this review, we attempted to establish that oral health is essential for systemic health, especially in patients with NAFLD. 相似文献
24.
Hiroshi Majima Toshio Izaki Sumiko Sanuki 《Metallurgical and Materials Transactions B》1985,16(2):187-194
The stripping of Fe(III)-loaded D2EHPA, which is known to be difficult, was studied in the presence of SO2. The stripping reaction of Fe(III) was greatly accelerated by the presence of SO2, generating Fe(II) as a stripped species. In the presence of SO2, the stripping of Fe(III) was favorable with all acids studied, including HC1, HC1O4, and H2SO4, and even with water. Among various factors, the partial pressure of SO2 was found to be the most important factor in controlling the rate of stripping as well as the rate of reduction of stripped
Fe(III) in the aqueous phase. The removal of SO2 dissolved in an organic phase was easily done by washing with aqueous H2O2 solution. 相似文献
25.
Hemimicropsia is a rare disorder of visual perception characterized by an apparent reduction of the size of objects when presented in one hemifield. We report two cases of hemimicropsia resulting from focal brain lesions. The first patient was an art teacher and could accurately depict his abnormal visual perception. He subsequently died and his brain was examined post mortem. In the second patient, micropsia was assessed by a quantified size comparison task. The size of a given object is normally perceived as constant across any spatial position. Hemimicropsia may thus be considered a limited violation of the size constancy principle. Behavioural and anatomical data are discussed in relation to the neural basis of visual object perception in humans. 相似文献
26.
Kohji Hizume Tonau Nakai Sumiko Araki Eloise Prieto Kenichi Yoshikawa Kunio Takeyasu 《Ultramicroscopy》2009
In order to reveal the roles of histone tails in the formation of higher-order chromatin structures, we employed atomic force microscopy (AFM), and an in vitro reconstitution system to examine the properties of reconstituted chromatin composed of tail-less histones and a long DNA (106-kb plasmid) template. The tail-less nucleosomes did not aggregate at high salt concentrations or with an excess amount of core histones, in contrast with the behavior of nucleosomal arrays composed of nucleosomes containing normal, N-terminal tails. Analysis of our nucleosome distributions reveals that the attractive interaction between tail-less nucleosomes is weakened. Addition of linker histone H1 into the tail-less nucleosomal array failed to promote the formation of 30 nm chromatin fibers that are usually formed in the normal nucleosomal array. These results demonstrate that the attractive interaction between nucleosomes via histone tails plays a critical role in the formation of the uniform 30-nm chromatin fiber. 相似文献
27.
Motoi Oshima Wataru Shimada Shunsuke Hashimoto Atsushi Tani Kazunari Ohgaki 《Chemical engineering science》2010,65(20):5442-5446
Recrystallization in a tetragonal tetra-n-butyl ammonium bromide (hereafter, TBAB) semi-clathrate hydrate system has been investigated in TBAB aqueous solutions of two different concentrations (stoichiometric mole fraction for tetragonal TBAB hydrate formation and lower mole fraction than stoichiometric one) by use of optical microscopy. The recrystallization of TBAB hydrate has been observed under milder condition than that of the initial crystallization in both concentrations. In particular, solution of the lower concentration is easily recrystallized. This is the first observation of memory effect in a semi-clathrate hydrate system. In addition, the recrystallization occurs in the vicinity of the place where the last piece of initial crystal was dissociated. This implies that a small amount of residual structures remain in the dissociated water, but unfortunately they cannot be confirmed with Raman micro-spectroscopy. 相似文献
28.
Sumiko Sanuki Katsuhiro Matsushita Motoya Nishiwaki Hiroshi Majima 《Metallurgical and Materials Transactions B》2000,31(1):5-13
The preparation of fine particles of Nd(III) carbonate from kerosene solution, from which Nd(III) was extracted with versatic
acid 10 (VA10) by a precipitation stripping technique using an aqueous NH3-(NH4)2CO3 solution as stripping medium, was studied.
In preliminary experiments, we were unable to recover simple Nd(III) carbonate from Nd(III)-loaded VA10 by CO2 gas bubbling, when water, (NH4)2CO3, NH4HCO3, NaHCO3, or NA2CO3 solution saturated with CO2 was used as the stripping solution.
To obtain simple Nd(III) carbonate, it is necessary to use more than the stoichiometric amount of NH3 compared to VA10 and about 10 times as much (NH4)2CO3 as Nd(III). The solution mixture of NH3-(NH4)2)CO3 acts as a pH buffer, an adductor for VA10, and a CO
3
2−
ion source. Although it was concluded that the precipitates are Nd2(CO3)3·xH2O (x⊧4), their X-ray pattern does not coincide with that quoted by JCPDS. By heating these precipitates, cubic Nd2O3 was obtained at 823 K, while, at 973 K, hexagonal Nd2O3 was formed. Since the stripping solution consisting of NH3-(NH4)2CO3 was highly alkaline, VA10 was also stripped in the aqueous phase. To use a closed-circuit system for the precipitation stripping
of Nd(III) carbonate from Nd(III)-loaded VA10, it is important to regenerate VA10 in the organic phase. For this purpose,
evaporation of NH3 by air bubbling was studied. By bubbling air into a stripping solution warmed at 333 K, almost all the VA10 can be transferred
to the organic phase. 相似文献
29.
The effect of turbulence on nitrifying biofilms was studied in five cylindrical PVC (polyvinyl chloride) reactors, each having ten biofilm sampling taps, over a period of 196 days. Bulk water in the reactors was stirred by paddles at 32, 92, 140, 278 and 500 rpm and the turbulent intensities measured at 10 mm from the wall were 0.6, 1.5, 2.6, 4.4 and 8.9 cm/s. Biofilms appeared as isolated colonies and continued to grow as filament-type biofilms. Higher turbulence resulted in higher NH4-N flux and higher areal biomass density. Turbulent diffusion of substrates and by-products in the vicinity of filament-type biofilms must have resulted in the above phenomena. Photographic observation of the biofilm surfaces on sampling taps showed uniform biofilm filaments at higher turbulent intensities and large variation in the height of filaments at low turbulent intensities. Substrate flux and biofilm structure (areal density, filament height and cross-sectional area of filament) are inter-related parameters and are strongly affected by turbulence near the biofilm. Substrate flux is expressed as a power function of turbulent intensity, volumetric density and substrate concentration for filament-type biofilm when substrates are non-limiting. 相似文献
30.
Pseudomonas aeruginosa, a gram-negative rod bacterium, is a causative agent of waterborne pneumonia and presents high tolerance against conventional disinfectants. The inorganic biocidal reagents, copper and silver, were applied to inactivate P. aeruginosa inoculated in a synthetic drinking water (SDW). Additionally, the relationship of the specific amount of accumulated copper and silver reagents (Cs) on P. aeruginosa with inactivation profile was elucidated in this study. Flow cytometry (FCM) following staining with SYTO 9 and PI was used for detection of bacterial viability and density. Individual copper and silver reagents, and their combination, exhibited excellent biocidal abilities even at the concentration of 0.05 mgCu/L and 0.005 mgAg/L. The critical amounts of accumulated disinfectant (Cs) were calculated at 2.82 x 10(-7) microgCu/cells and 5.13 x 10(-8) microgAg/cells; at an incubation of 70 h. Consequently, the role of disinfectant on the inactivation of P. aeruginosa and the assessment of biocidal ability of copper, silver, and their combination were successfully explained by evaluating the terms Cs and Cc. 相似文献