Changes in diet and lifestyle in recent years have led to unhealthy dietary patterns and inadequate physical activity, making it difficult to maintain an appropriate energy balance, which results in an increased prevalence of diet-related chronic diseases such as obesity, diabetes, cardiovascular disease, and certain types of cancer. The importance of the roles of lipids in these diseases is now recognized. Dietary fatty acids modulate inflammatory processes and contribute to the pathophysiological state of diet-related chronic diseases. Although there is insufficient evidence as to the involvement of monounsaturated fatty acids in inflammatory processes and limited evidence indicating a potential proinflammatory role of saturated and trans fatty acids, there is considerably stronger evidence suggesting that increasing the intake of n-3 polyunsaturated fatty acids brings about favorable antiinflammatory effects. Certain fatty acids may also produce therapeutic effects by modifying the activity of ghrelin, a growth hormone-releasing and appetite-stimulating peptide; such modification may yield reduction of food intake and enable clinical manipulation of energy metabolism.

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Excessive indoor air pollution can cause sick building syndrome (SBS), cases of which still occur in Japanese homes despite strict regulations on the value of indoor chemical substances established by the Ministry of Health Labour and Welfare. Idiopathic environmental intolerance (IEI), so-called multi-chemical sensitivity (MCS) has become another issue because it is caused by an extreme low concentration of chemical substances. These problems are discussed from the viewpoint of environmental hygiene in the present study. First, indoor air quality and its adverse effect on health is reviewed according to the history of sick buildings. Next, the factors concerning indoor air quality are indicated, and then measures to combat these problems are considered to improve the indoor environment. No ideal solution has been found: however, we summarize important knowledge on research to regain patient health as a result SBS and MCS.

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Tremendous progress in pathogenic role of cyclooxygenase-2 (COX-2) in diverse cancers triggering the cancer research in the direction of COX-2 inhibitors. Several experimental studies reported overexpression of COX-2 in cancer cells. Mechanisms mediating the pathobiology of COX-2 in cancer are still unclear and needs to be clarified. However, recent studies have shown that the levels of COX-2 isoenzymes are elevated in certain cancers like colo-rectal carcinoma, squamous cell carcinoma of head and neck and certain cancers of lung and breast. Our review article aims to summarize the role of COX-2 in various types of cancer and mechanisms emerged from recent research and their interaction with other cytokines. It seems mechanisms mediating COX-2 and its role in each cancer may be different. In general, possible signaling from the lipids (prostaglandins) can inhibit apoptosis and increase proliferation, motility, and metastatic potential. Furthermore, under certain conditions COX-2 can contribute to angiogenesis. Even, COX-2 is found in lung cancer cells that are responsible for suppressing patients' immune systems and therefore contributing to the growth of lung cancer. COX-2 inhibitors are already in clinical trials for the prevention of colorectal, oral, skin, esophageal and non-small-cell lung cancers and for the treatment of cervical, prostate, and metastatic breast cancers. Heightened role of COX-2 in cancer prompts the pharmaceutical research to design new and safer COX-2 inhibitors to minimize the cardiovascular side effects and improves the treatment of cancer.

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In the present study, we investigated the oxidative stress induced by arsenical compounds in mice. Catalase (CAT) activity in the liver was decreased significantly when an organic arsenical compound, diphenylarsinic acid (DPAA), was administered to mice for 7 and 28 consecutive days. Reduced glutathione (GSH) was decreased significantly in the blood of the mice treated for 7 days with another organic arsenical, phenylmethyl arsonic acid (PMAA), and an inorganic arsenical, Na₂HAsO₄, as well as DPAA. GSH was also decreased significantly in the brain of the mice treated for 28 days with DPAA. Arsenic concentrations in the brain of the mice administered DPAA for 7 or 28 days were 1.6-3.0 times higher than those in the livers of these mice. The levels were about 3.0-14 times higher than those in the brains of mice administered inorganic arsenicals, suggesting that organic arsenicals tended to be more highly accumulated in the brain than inorganic arsenicals. The Morris water maze test supported these results, i.e., the latency time of the mice administered DPAA was significantly longer than that of the mice administered Na₂HAsO₄ or NaAsO₂, as well as that of controls without arsenical. These results showed that DPAA decreased GSH in the blood, liver and brain, and that DPAA was more easily transferred to the brain. It was suggested that spatial learning ability was depressed by the accumulation of DPAA in the brain.

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N-methyl-D-aspartate receptors (NMDAR) belong to the ionotropic glutamate receptor subclass and are widely distributed in the vertebrate brain. Molecular cloning has revealed the existence of seven NMDAR subunits: one NMDAR1 (NR1), four different NMDAR2 (NR2A-D), and two different NMDAR3 (NR3A,B). Alternative splicing of the single NR1 gene generates eight isoforms with distinct functional properties. So far, the transcripts of the NR1 splice variants have been discriminated by Northern blot, in situ hybridization, or competitive polymerase chain reaction (PCR) methods all of which have their intrinsic limitations. In this study, we have developed a method to quantify the mRNAs of the NR1 splice variants by real-time PCR with the double-stranded DNA-binding dye SYBR Green I. The implementation of this assay will allow a better understanding of the regulatory mechanisms of the NR1 splice variants, and hence, their role in neuronal disease pathogenesis.

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Laccase is a polyphenol oxidase with the ability to oxidize a broad range of persistent organic pollutants, including benzo[a]pyrene, the most carcinogenic, mutagenic and teratogenic polycyclic aromatic hydrocarbons (PAHs). In this study, the reaction conditions for benzo[a]pyrene oxidation by laccase from Trametes versicolor were optimized in a liquid medium by a series of single factor experiments. The maximal benzo[a]pyrene oxidation rate was observed at 40°C, pH 4, 10% of acetonitrile and an incubation time of more than 24hr, and the benzo[a]pyrene oxidation was enhanced significantly by the addition of a mediator, 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonicacid) (ABTS). Laccase was also applied to aged PAHs polluted soil to examine the efficiency of enzymatic bioremediation. The results showed that the enzyme was still effective in the degradation of anthracene, benzo[a]pyrene and benzo[a]anthracene in soil. Moreover, the degradation rate of most PAHs increased by the addition of ABTS. Our results indicated that the bioremediation of PAHs contaminated soil using laccase is feasible but a suboptimal pH might be a limiting factor in the enzymatic treatment of soil.

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Sparassis crispa (SC), known as Hanabiratake in Japanese, is an edible mushroom with medicinal properties; however, its antidiabetic activity is not well established. In the present study, we examined the effects of dietary SC on diabetic mice. KK-Ay mice that were fed SC for 3 or 6 weeks showed pronounced increase of plasma levels of adiponectin. Significant decrease of blood glucose and insulin levels were also observed by 3 week-administration of SC. Moreover, mice that were fed the SC diet exhibited relatively decreased serum levels of triglycerides and total cholesterol. Although the SC diet had no effect on body and adipose tissue weights in KK-Ay mice, the size of the mesenteric adipose cells of SC group was smaller than control group though it was not significant difference. Thus, the SC diet might decrease the adipose cell size in order to increase plasma adiponectin levels. Considering the physiological significance of adiponectin in type 2 diabetes, insulin resistance, and cardiovascular diseases, these findings imply that dietary SC has the potential to ameliorate these diseases.

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An analytical method was developed for simultaneous determination of trace amounts of nine corticosteroids in sewage-treatment-plant (STP) samples. The compounds studied were prednisolone, dexamethasone, betamethasone, triamcinolone acetonide, fluocinolone acetonide, prednisolone acetate, hydrocortisone acetate, betamethasone valerate, and betamethasone dipropionate. The method involves concentration and purification of analytes by solid-phase extraction, subsequent separation by liquid chromatography, and detection by mass spectrometry. Quantitative analysis was performed by the standard addition method. Instrument detection limits were in the range 1.6-9.4 pg for the target compounds. Recoveries were 57.2-106.7% in the STP influent sample and 59.1-112.5% in the STP effluent sample with relative standard deviations of 8.7-19.2% and 7.3-17.1%, respectively. This method was used for the determination of these chemicals in STP samples from Takase (Funabashi, Japan); some corticosteroids were determined at levels as low as single nanograms per liter.

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The present study defined a simplified physiologically based pharmacokinetic (PBPK) model for 1,4-dioxane in humans based on in vitro metabolic parameters determined using relevant liver microsomes, coefficients derived in silico, physiological parameters derived from the literature, and a developed PBPK model in rats. The model consists of a chemical absorption compartment, a metabolizing compartment, and a central compartment for 1,4-dioxane. Evaluation of the rat model was performed by comparisons with experimental pharmacokinetic values from blood and urine obtained from rats in vivo after daily oral treatment with 1,4-dioxane (500 mg/kg, a no-observed-adverse-effect level) for 14 days. Elimination rates of 1,4-dioxane in vitro were established using data from rat liver microsomes and from pooled human liver microsomes. 1,4-Dioxane was expected to be absorbed and cleared rapidly from the body in silico, as was the case for rats confirmed experimentally in vivo with repeated low-dose treatments. These results indicate that the simplified PBPK model for 1,4-dioxane is useful for a forward dosimetry approach in humans. This model may also be useful for simulating blood concentrations of other related compounds resulting from exposure to low chemical doses.

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The present study defined a simplified physiologically based pharmacokinetic (PBPK) model for dichlorodiphenyltrichloroethane [1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane, DDT] in humans based on metabolic parameters determined in vitro using relevant liver microsomes, coefficients derived in silico, physiological parameters derived from the literature, and an established rat PBPK model. The model consists of an absorption compartment, a metabolizing liver compartment, and a central compartment for DDT. Evaluation of the rat model was performed by making comparisons between predicted concentrations in blood and in vivo experimental pharmacokinetic values obtained from rats after daily oral treatment with DDT (10 mg/kg, a no-observed-adverse-effect level) for 14 days. Elimination rates of DDT in vitro were established from data from rat liver microsomes and from pooled human liver microsomes. The ratio of intrinsic clearance values of DDT based on rat in vivo and rat in vitro experiments was used as the scaling factor for estimating in vivo hepatic intrinsic clearance in humans in the final human PBPK model. These results indicate that a simplified PBPK model for DDT is useful for a forward dosimetry approach in rats and/or humans and for estimating blood concentrations of other related compounds resulting from exposure to low chemical doses.

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N-Nitrosodialkylamines, activated metabolically by cytochrome P450, possess mutagenic and carcinogenic activity. In this study, the hydroxyl radical, generated from Fenton's reagent, was used as an oxidant for the activation of the N-nitrosodialkylamines. Ethyl acetate extract from the reaction mixture which included Fe²⁺-Cu²⁺-H₂O₂ and N-nitrosodialkylamines; N-nitrosodimethylamine (NDM), N-nitrosodiethylamine (NDE), N-nitrosodipropylamine (NDP), N-nitrosodibutylamine (NDB), N-nitroso-N-methylpropylamine (NMP), N-nitroso-N-methylbutylamine (NMB), were assayed for their mutagenicity in Salmonella typhimurium (S. typhimurium) TA1535 and Escherichia coli (E. coli) WP2 uvrA. Although Fenton's reagent (Fe²⁺-H₂O₂) alone did not activate NMB, the addition of the copper ion to the reaction with Fenton's reagent (Fe²⁺-Cu²⁺-H₂O₂) resulted in the production of mutagens. While the extracts of the reaction of NDM or NDE with Fe²⁺-Cu²⁺-H₂O₂ were not mutagenic, those of NMP, NDP, NMB, or NDB with Fe²⁺-Cu²⁺-H₂O₂ were mutagenic in both S. typhimurium TA1535 and E. coli WP2 uvrA. These results demonstrate that a direct-acting mutagen was formed from N-nitrosodialkylamines, with alkyl chains longer than propyl, by the oxidation in the Fe²⁺-Cu²⁺-H₂O₂ system.

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Genetic mutation is a trigger for the generation of malignant cells and an aberrant epigenetic status contributes to the maintenance of mutations and proliferation of mutated cells. Along with DNA methylation, histone modifications such as acetylation and methylation are significant to biological processes. Histone deacetylases (HDACs) are important epigenetic regulators of chromatin modifications and gene expression. Though several HDAC inhibitors are currently being tested in clinical trials, the roles of HDACs in malignant transformation remain unknown. Here, we showed that the expression of two forms of Hdac9, a full-length version (Hdac9FL) and a splicing variant lacking exon 7 (Hdac9Δ7), both class IIa HDACs, was up-regulated during chemically induced hepatocarcinogenesis. In addition, we found that HDAC9FL and HDAC9Δ7 are located in the nucleus and cytoplasm, respectively. We also found their nuclear localization and nuclear export signals to be encoded in exon 7 and exon 25, respectively. Though the two isoforms could not transform mouse NIH-3T3 fibroblasts, they promoted tumor cell anchorage-independent growth on soft agarose. The HDAC9 variants do not seem to cause cell transformation, but cytoplasmic and nuclear HDAC9 may contribute to the survival of malignant cells in the early stages of hepatocarcinogenesis.

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The immune response plays an important role in the development of allergic diseases. It is established that a complex network of various immunocytes such as Th2, non-Th2 (Th17), and regulatory T (Treg) participate in allergic reactions. In this study, we examined the frequencies of Th17 cells (IL-17-positive cells) and Treg cells (FOXP3-positive cells) in the peripheral blood and elucidated their participation in pediatric allergic diseases such as bronchial asthma and food allergies. Our study included 35 subjects, 27 with allergic diseases (19 with asthma and 8 with food allergies) and 8 were controls (without any allergic diseases); their age ranged from 1 to 13 years. The frequency of Th17 cells (IL-17-positive cells) among the CD4⁺T cells in the peripheral blood was 2.33±1.29% in patients with bronchial asthma, 1.53±1.34% in those with food allergies, and 1.50±0.809% in controls. These results indicated that only the patients with bronchial asthma had a trend towards a higher frequency of Th17 cells (p=0.1558). The ratio of Th17 cells to Treg cells did not show any statistical correlation among the patients with bronchial asthma. However, when we excluded the patients with a severe type of asthma, we could obtain an inverse trend between the ratio of Th17 cells to Treg cells (p=0.1655). This study suggested that Th17 cells and Treg cells participate in pediatric allergic reactions such as bronchial asthma.

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A rapid gas chromatography-mass spectrometry (GC-MS) method was developed and validated for the analysis of eperisone in serum using monolithic spin-column extraction. The linear concentration range for eperisone was 2-2500 ng/ml. The limit of detection was found to be 0.5 ng/ml. The average extraction recovery range was 92.8-96.0%. The intra- and interday relative standard deviations (RSDs) of the concentrations were less than 12.6% and 12.5%, respectively. The accuracy of this method ranged from 95.0% to 98.3%. We successfully used this assay to analyze serum samples from an eperisone-overdose patient. Our method has some analytical advantages compared with previously reported gas chromatography (GC) and GC-MS methods, such as higher selectivity and sensitivity than GC with nitrogen-phosphorus detection and the avoidance of nonspecificity, the ability to use a smaller sample volume than that required for the GC-MS method, and a shorter sample preparation time than the previous solid-phase extraction (SPE) method.

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We describe a simple and practical method for the analysis of phosphorus-containing amino acid-type herbicides and their decomposition products without derivatization by capillary electrophoresis/mass spectrometry using a chemically modified capillary having amino groups. The compounds were glyphosate (GLYP), glufosinate (GLUF), bialaphos (BIAL), aminomethylphosphonic acid (AMPA) and 3-methylphosphinicopropionic acid (MPPA). AMPA and MPPA are the decomposition products of GLYP and GLUF, respectively. The optimum running conditions were found to be 100 mM formic acid adjusted to pH 3.4 with 100 mM ammonia with an applied voltage of -30 kV using an amino capillary (FunCap-CE/Type A) and mass spectrometry. The five compounds were separately determined within 10 min. Relative standard deviations of the migration times of analytes were less than 0.52%. Total analysis time of the proposed method was 1/6 to 1/3 of that of gas chromatography/mass spectrometry methods. The method was applicable for the analysis of these compounds in soil and tea beverage samples. The decomposition rates of GLYP, GLUF and BIAL in soil are discussed.

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Lactoferrin (Lf) is a multifunctional protein that has inhibitory activity against microorganisms. In this study, the effects of Lf on the growth of human parainfluenza virus type 2 (hPIV-2) in LLCMK₂ cells were investigated. Lf inhibited cell fusion and hemadsorption induced by hPIV-2. However, virus RNA synthesis was only slightly inhibited by Lf. In addition, indirect immunofluorescence study showed that virus protein syntheses were not completely inhibited by Lf. Using a recombinant, green fluorescence protein-expressing hPIV-2 (rghPIV-2), it was found that virus entry into cells were considerably inhibited by Lf, but cell-to-cell spread was not inhibited. The number of viruses produced by the cells were determined, and it was found that Lf reduced the number of released viruses to about 1/300 compared with that of positive control. Lf bound to cell surface within 10 min at early phase of infection, it assembled gradually, and many aggregates were observed at 120 min. These results indicated that Lf considerably inhibited virus adsorption to the surface of the cells by binding to the cell surface and prevented hPIV-2 infection.

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Cationic and amphiphilic antimicrobial peptides (AMPs) such as α-defensins and cathelicidins are factors related to innate immunity. In the present study, we examined the protective effects of two AMPs, human neutrophil peptide-3 and α-defensin-5, against the opportunistic pathogen Enterococcus faecalis (E. faecalis). The α-defensins had dose-dependent bactericidal activity, whereas they showed no synergistic effect on the antimicrobial actions of antibiotics. Although AMPs often neutralize bacterial bioactive products, neither α-defensin reduced the proteolytic activity of GelE, a toxic protease from E. faecalis. On the other hand, the α-defensins were found to be fairly stable even in the presence of excess amounts of GelE. These results indicate that α-defensins may be defensive factors against E. faecalis in humans.

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