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Aluminium (Al) levels of 90 food samples were investigated. Nineteen samples contained Al levels exceeding the tolerable weekly intake (TWI) for young children [body weight (bw): 16 kg] when consuming two servings/week. These samples were purchased multiple times at specific intervals and were evaluated for Al levels. Al was detected in 27 of the 90 samples at levels ranging from 0.01 (limit of quantitation) to 1.06 mg/g. Of these, the Al intake levels in two samples (cookie and scone mix, 1.3 and 2 mg/kg bw/week, respectively) exceeded the TWI as established by European Food Safety Authority, although the level in the scone mix was equivalent to the provisional TWI (PTWI) as established by Joint Food and Agriculture Organization of the United Nations/World Health Organization Expert Committee on Food Additives. The Al levels markedly decreased in 14 of the 19 samples with initially high Al levels. These results indicated reductions in the Al levels to below the PTWI limits in all but two previously identified food samples.  相似文献   
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Migration from multi-layer laminated film pouches intended for retort foods was investigated through HPLC analysis with a fluorescence detector, and measurements of residue on evaporation, consumption of potassium permanganate and total organic carbon. HPLC analysis revealed that the levels of migrants in oil and the water which were heated in the pouches (121 degrees C, 30 min) were ten times of those in the corresponding official simulants under the official conditions; n-heptane (25 degrees C, 60 min), and water (95 degrees C, 30 min). Bisphenol A diglycidyl ether and related compounds were found in the oil and the water heated in the pouches, as well as in the simulants. These compounds were thought to have been present in the adhesive between the laminated films, and migrated through the food-contact film of the package. Consumption of potassium permanganate and residue on evaporation of the heated water were ten times of those of the water simulant, while the total organic carbon level of the heated water was several-hold greater than that of the water simulant. In addition, migrant levels per surface area of the pouch were one-fourth of the concentrations per content volume of the pouch. Since compliance with the legal limits is evaluated based on the concentration per surface area, real migration into foods would be underestimated by a factor of another four.  相似文献   
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Herbicidins A and B, two new antibiotics with selective and contact herbicidal activity, were produced by a new species of Streptomyces designated as S. sagononensis. Among tested microorganisms, herbicidins indicated some activity against fungi in vitro and Xanthomonas oryzae in vivo. Their characteristic features were brought into relief by their selective and contact killing effect on many dicotyledonous plant as well as their inhibition of germination of the plant seeds, such as Chinese cabbage.  相似文献   
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The enzyme catalyzing conversion of N alpha-benzyloxycarbonyl-L-aminoadipic-delta-semialdehyde (N alpha-Z-L-AASA) to N alpha-benzyloxycarbonyl-L-aminoadipic acid (N alpha-Z-L-AAA) in Rhodococcus sp. AIU Z-35-1 was identified, and its characteristics were revealed. This reaction was catalyzed by a dehydrogenase with a molecular mass of 59 kDa. The dehydrogenase exhibited enzyme activity on not only N alpha-Z-L-AASA but also N alpha-Z-D-AASA and short chain aliphatic aldehydes, but not on aromatic aldehydes and alcohols. The apparent Km values for N alpha-Z-L-AASA, N alpha-Z-D-AASA and NAD+ were estimated to be 3.8 mM, 14.1 mM and 0.16 mM, respectively. The NH2 terminal amino acid sequence of this enzyme exhibited a similarity to those of a piperidein-6-carboxylate dehydrogenase from Streptomyces clavuligerus and a putative dehydrogenase from Rhodococcus sp. RHA 1, but not to those of other microbial aldehyde dehydrogenases.  相似文献   
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Interleukin (IL) 23 (p19/p40) plays a critical role in the pathogenesis of psoriasis and is upregulated in psoriasis skin lesions. In clinical practice, anti-IL-23Ap19 antibodies are highly effective against psoriasis. IL-39 (p19/ Epstein-Barr virus-induced (EBI) 3), a newly discovered cytokine in 2015, shares the p19 subunit with IL-23. Anti-IL-23Ap19 antibodies may bind to IL-39; also, the cytokine may contribute to the pathogenesis of psoriasis. To investigate IL23Ap19- and/or EBI3-including cytokines in psoriatic keratinocytes, we analyzed IL-23Ap19 and EBI3 expressions in psoriasis skin lesions, using immunohistochemistry and normal human epidermal keratinocytes (NHEKs) stimulated with inflammatory cytokines, using quantitative real-time polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), and liquid chromatography-electrospray tandem mass spectrometry (LC-Ms/Ms). Immunohistochemical analysis showed that IL-23Ap19 and EBI3 expressions were upregulated in the psoriasis skin lesions. In vitro, these expressions were synergistically induced by the triple combination of tumor necrosis factor (TNF)-α, IL-17A, and interferon (IFN)-γ, and suppressed by dexamethasone, vitamin D3, and acitretin. In ELISA and LC-Ms/Ms analyses, keratinocyte-derived IL-23Ap19 and EBI3, but not heterodimeric forms, were detected with humanized anti-IL-23Ap19 monoclonal antibodies, tildrakizumab, and anti-EBI3 antibodies, respectively. Psoriatic keratinocytes may express IL-23Ap19 and EBI3 proteins in a monomer or homopolymer, such as homodimer or homotrimer.  相似文献   
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It has been reported that saliva may play an important role in the prevention and development of enamel caries and that both lipids and protein contents in saliva may be relevant to this role. This study examined the lipid and protein levels in saliva from individuals differing in caries experience. Female subjects (20 to 21 years old) were used divided equally into two groups, caries-susceptible group (CSG) and caries-resistant group (CRG). Stimulated parotid saliva and stimulated whole saliva were collected from the subjects. After centrifugation, each saliva sample was analyzed for the concentrations of lipids and proteins and for the compositions of lipids and fatty acids. The lipid and protein contents in parotid saliva increased in proportion to increase of the flow rate. The lipid content was slightly correlated with the protein one (r = 0.33). Total lipid and protein concentrations were higher in the samples from CSG than those from CRG. The lipid composition was similar in the samples from the two groups; more than half in total lipids was neutral lipids, followed by glycolipids and phospholipids. Neutral lipids and free fatty acid and triacylglyceride concentrations were significantly higher in the samples from CSG than those from CRG (p<0.01 for each). Also stearic, linoleic and docosahexaenoic acids were significantly higher in the former group than the latter one (p<0.05 and p<0.01). In summary, the lipid concentrations in parotid saliva from caries susceptible subjects were higher than those from caries resistant ones, and the difference in fatty acid composition was detected between them. The variations in the lipid levels and fatty acid composition may be associated with those in caries development.  相似文献   
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Multiple current dipole estimation using simulated annealing   总被引:4,自引:0,他引:4  
A method for estimating electrical current distribution in the human brain using a multiple current dipole model is presented. A cost function for estimating multiple dipoles is proposed and a simulated annealing algorithm is used to obtain an acceptable solution. Computer simulation is used to evaluate the effectiveness of this method  相似文献   
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