O-064 Recovery culture of human cryopreserved blastocysts with prolactin after warming improves trophoblast outgrowth

Study question

Does prolactin (PRL) treatment during recovery culture affect human blastocyst outgrowth?

Summary answer

PRL treatment for 120 min promoted trophoblast outgrowth in cryopreserved human blastocysts by upregulating the expressions of epithelial-to-mesenchymal transition (EMT) and focal adhesion-related genes.

What is known already

Human embryos express the PRL receptor at the morula and the blastocyst stages. This expression correlates with the blastocyst diameter and the time required for the embryos to reach the blastocyst stage. Treatment with PRL from cleavage to the blastocyst stage improves blastocyst outgrowth to fibronectin. However, whether PRL treatment after warming cryopreserved blastocysts cultured to the blastocyst stage without PRL influences outgrowth competence remains unknown. Furthermore, the optimal time for post-warming PRL treatment remains to be ascertained.

Study design, size, duration

A total of 374 discarded human vitrified blastocysts donated for research by consenting couples were used. The study was approved by the Institutional Review Board. The blastocysts were randomly allocated to two groups, to be cultured in medium either with PRL (n = 208) or without PRL (control; n = 166). The gene expression level, blastocyst adhesion, outgrowth area, and distance of trophoblast migration were compared between the groups.

Participants/materials, setting, methods

Vitrified human blastocysts were cultured for 120 min after warming. Some blastocysts were treated with PRL for 15–120 min during the recovery period. The blastocysts were plated on fibronectin-coated dishes and cultured to assess blastocyst adhesion and outgrowth. The expressions of PRL-interacting genes were assessed by quantitative RT-PCR 12 h after outgrowth culture. The migration distance at the outer edge of the trophoblast cells was examined using time-lapse systems.

Main results and the role of chance

The mRNA expressions of ezrin, radixin, and moesin, which regulate cell adhesion and invasion by controlling actin reorganisation during EMT, was stimulated by PRL treatment for 120 min. The expressions of EMT-related genes, transforming growth factor β1, snail1, and twist1 were also promoted by treatment with PRL for 120 min. The blastocysts treated with PRL also exhibited augmented expression of cadherin2 and transcriptional repression of cadherin1. Higher mRNA expressions of integrin-based focal adhesion-related genes, ITGA5 and ITGB1, were observed after treatment with PRL for 120 min compared to that in the other groups. PRL treatment for 120 min did not alter the rate of blastocyst adhesion to fibronectin-coated dishes 96 h after the outgrowth culture assay. However, multiple linear regression analysis revealed that the outgrowth area was significantly increased in blastocysts treated with PRL. The migration distance of trophoblast cells was significantly increased after PRL treatment. Furthermore, a more beneficial effect of prolactin treatment on blastocyst outgrowth was observed when the blastocysts were vitrified on day 5 compared to that when the blastocysts were vitrified on day 6. Moreover, the outgrowth area was increased by PRL treatment when the blastocyst diameter was larger than 180 µm.

Limitations, reasons for caution

The results may vary between in vivo and in vitro conditions. Further clinical studies are required to explore the clinical efficacy of PRL treatment.

Wider implications of the findings

This study showed that PRL treatment for 120 min improved trophoblast migration in cryopreserved human blastocysts. Therefore, recovery culture with PRL treatment post-warming followed by blastocyst transfer could improve pregnancy outcomes.

Trial registration number

not applicable

Pressure-induced reconstitution of Fermi surfaces and spin fluctuations in S-substituted FeSe

FeSe is a unique high-\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$T_c$$\end{document}Tc iron-based superconductor in which nematicity, superconductivity, and magnetism are entangled with each other in the P-T phase diagram. We performed \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{77}$$\end{document}77Se-nuclear magnetic resonance measurements under pressures of up to 3.9 GPa on 12% S-substituted FeSe, in which the complex overlap between the nematicity and magnetism are resolved. A pressure-induced Lifshitz transition was observed at 1.0 GPa as an anomaly of the density of states and as double superconducting (SC) domes accompanied by different types of antiferromagnetic (AF) fluctuations. The low-\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$T_{\mathrm{c}}$$\end{document}Tc SC dome below 1 GPa is accompanied by strong AF fluctuations, whereas the high-\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$T_{\mathrm{c}}$$\end{document}Tc SC dome develops above 1 GPa, where AF fluctuations are fairly weak. These results suggest the importance of the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$d_{xy}$$\end{document}dxy orbital and its intra-orbital coupling for the high-\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$T_{\mathrm{c}}$$\end{document}Tc superconductivity.

O-223 Fatty acid supplementation into warming solutions improve the developmental competence of mouse, bovine, and human oocytes and embryos after vitrification

Study question

Does fatty acid (FA) supplementation into vitrification and warming solutions influence the developmental competence of oocyte and embryo after vitrification and warming?

Summary answer

FA supplementation during the warming process improves the developmental competence of vitrified-warmed mouse oocytes and embryonic-morphologies after vitrification at the cleavage-stage in bovines and humans.

What is known already

Vitrified metaphase II stage oocytes exhibit a diminished ability to develop into blastocysts and live births. Previous studies have shown reduction in intracellular lipid content as one of the factors associated with reduced developmental competence of oocytes after vitrification as the intracellular lipid content of oocytes is affected by vitrification. FAs derived from break down of lipids are primarily transferred to the mitochondria, where it plays a crucial role in cellular metabolism. However, the effects of FA supplementation in warming solutions on the cytoplasmic lipid content and subsequent embryo development are unknown.

Study design, size, duration

A chemically defined FA mixture was added to the vitrification and/or warming solutions. Oocytes collected from C57BL6/N (n = 80) were randomly divided into three groups (fresh, n = 634; non-FA (control), n = 961; FA, n = 1,686), and were vitrified-warmed with/without FA. Lipid composition, developmental competence, and gene expression levels were compared among the groups. Bovine embryos (fresh, n = 420; control, n = 524; FA, n = 492) and discarded human day-2 embryos (control, n = 87; FA, n = 92) were used to examine the developmental competence of embryos.

Participants/materials, setting, methods

Lipids in the ooplasm were stained with Nile red and the fluorescence intensity was analysed. The developmental competence of mouse oocytes was examined by performing intracytoplasmic sperm injection. Expressions of FA metabolism-related genes were measured. The bovine embryos were vitrified at the four-cell stage and cultured to the blastocyst stage after warming. Cryopreserved discarded human embryos were warmed and cultured. The obtained blastocysts were then placed on fibronectin-coated dishes to examine the outgrowth formation.

Main results and the role of chance

Lipid content of mouse oocytes was significantly lower in the control group compared to that in the fresh group (P < 0.05). On the contrary, lipid contents of FA and fresh groups were comparable (P = 0.24). Blastocyst formation rate was significantly higher in the FA group than that in the control group (55.7% and 44.8%, respectively; P < 0.05). To examine the optimal timing for FA supplementation, FA was added to the vitrification solution (FAvit), warming solution (FAthaw), and/or both solutions (FAvit-thaw). Blastocyst formation rate was significantly higher in the FAthaw group than that in the control group (59.8% and 50.0%, respectively; P < 0.05). The mRNA expressions of Acaa2 and Hadha in mouse embryos were significantly higher in the FAthaw group compared to that in the control group (P < 0.05). Moreover, FA supplemented warming solutions significantly improved the blastocyst formation rate in bovines (control, 53.5%; FAthaw, 64.5%; P < 0.05). Developmental rate to the expanded blastocyst stage was slightly improved in human embryos (control, 53.7%; FAthaw, 63%; P = 0.38) and the proportion of Grade A in inner cell mass and trophectoderm was significantly higher in the FAthaw group than that in the control group (P < 0.05). There were no differences in the outgrowth abilities between the control and FAthaw groups.

Limitations, reasons for caution

Since the experiments of the current study on human embryos were performed in vitro using discarded embryos, in vivo developmental ability was not evaluated. Therefore, to validate the application of our findings in human assisted reproductive technologies, further clinical trials (ART) are warranted.

Wider implications of the findings

FA supplementation into the warming solutions improved the developmental competence of vitrified–warmed oocytes and cleaved embryos by activating the β-oxidation pathway. These results indicate that FA supplementation into warming solutions is a potential strategy to improve clinical outcomes in human ART.

Trial registration number

not applicable

Female dominance of both spatial cognitive dysfunction and neuropsychiatric symptoms in a mouse model of Alzheimer's disease

Alzheimer’s disease (AD) is a prevalent neurological disorder affecting memory function in elderly persons. Indeed, AD exhibits abnormality in cognitive behaviors and higher susceptibility to neuropsychiatric symptoms (NPS). Various factors including aging, sex difference and NPS severity, are implicated during in development of AD. In this study, we evaluated behavioral abnormalities of AD model, PDAPP transgenic mice at young age using the Morris Water Maze test, which was established to assess hippocampal-dependent learning and memory. We found that female AD model mice exhibited spatial learning dysfunction and highly susceptible to NPS such as anxiety and depression, whereas spatial reference memory function was comparable in female PDAPP Tg mice to female wild type (WT) mice. Spatial learning function was comparable in male AD model mice to male WT mice. Multiple regression analysis showed that spatial learning dysfunction was associated with NPS severity such as anxiety and depression. Furthermore, the analysis showed that spatial reference memory function was associated with status of depression, but not anxiety. Thus, these results suggest female dominance of spatial learning dysfunction in the AD model mice accompanying increased NPS severity. The understandings of AD model may be useful for the development of therapeutic agents and methods in human AD.

Dementia model mice exhibited improvements of neuropsychiatric symptoms as well as cognitive dysfunction with neural cell transplantation

Elderly patients with dementia suffer from cognitive dysfunctions and neuropsychiatric symptoms (NPS) such as anxiety and depression. Alzheimer’s disease (AD) is a form of age-related dementia, and loss of cholinergic neurons is intimately associated with development of AD symptoms. We and others have reported that neural cell transplantation ameliorated cognitive dysfunction in AD model mice. It remains largely unclear whether neural cell transplantation ameliorates the NPS of AD. It would be interesting to determine whether NPS correlates with cognitive dysfunctions before and after neural cell transplantation in AD model mice. Based on the revalidation of our previous data from a Morris water maze test, we found that neural cell transplantation improved anxiety and depression significantly and marginally affected locomotion activity in AD mice. A correlation analysis revealed that the spatial learning function of AD mice was correlated with their NPS scores both before and after cell transplantation in a similar manner. In contrast, in the mice subjected to cell transplantation, spatial reference memory function was not correlated with NPS scores. These results suggested the neural cell transplantation in the AD model mice significantly improved NPS to the same degree as cognitive dysfunctions, possibly via distinct mechanisms, such as the cholinergic and GABAergic systems.

Pressure-induced Lifshitz transition in FeSe$_{0.88}$S$_{0.12}$ probed via $^{77}$Se-NMR

Recently, FeSe$_{1-x}$S$_x$ systems have received much attention because of the unique pressure-temperature phase diagram. We performed $^{77}$Se-NMR measurements on a single crystal of FeSe$_{0.88}$S$_{0.12}$ to investigate its microscopic properties. The shift of $^{77}$Se spectra exhibits anomalous enhancement at $1.0~\mathrm{GPa}$, suggesting a topological change in the Fermi surfaces, so-called Lifshitz transition, occurs at $1.0~\mathrm{GPa}$. The magnetic fluctuation simultaneously changes its properties, which implies a change in the dominant nesting vector. Edited by: A. Goñi, A. Cantarero, J. S. Reparaz

Nuclear magnetic resonance on $LaFeAsO_{0.4}H_{0.6}$ at 3.7 GPa

A prototypical electron-doped iron-based superconductor $LaFeAsO_{1-x}H_x$ undergoes an antiferromagnetic (AF) phase for $x  \geq 0.49$. We performed NMR measurements on $LaFeAsO_{0.4}H_{0.6}$ at 3.7 GPa to investigate the magnetic properties in the vicinity of a pressure-induced QCP. The linewidth of $~^1H$-NMR spectra broadens at low temperatures below 30 K, suggesting that the ordered spin moments remain at 3.7 GPa. The coexistence of gapped and gapless spin excitations was confirmed in the ordered state from the relaxation time $T_1$ of $~^{75}As$. The pressure-induced QCP is estimated to be 4.1 GPa from the pressure dependence of the gapped excitation.   Edited by: A. Goñi, A. Cantarero, J. S. Reparaz

Relative abundance of Megamonas hypermegale and Butyrivibrio species decreased in the intestine and its possible association with the T cell aberration by metabolite alteration in patients with Behcet's disease (210 characters)

OBJECTIVES

We have previously demonstrated that the phylum Actinobacteria, the family Lactobacillaceae, and the genus Bifidobacterium increased in relative abundance of gut microbiota in patients with Behcet's disease (BD). The phylum Firmicutes and the class Clostridia were predominant in the feces of normal individuals. The class Clostridia includes short-chain fatty acid-producing bacteria, important for the balance between regulatory T cells and helper T type 17 (Th17) cells. It is possible that the bacterial compositional alteration causes low intestinal short-chain fatty acid concentrations, leading to skewed immune functions in patients with BD.

METHODS

To test the hypothesis, we examined species composition and gene functions from the 16S rRNA data by utilizing PICRUSt software.

RESULTS

We have shown that relative abundance of Eggerthella lenta, Acidaminococcus species, Lactobacillus mucosae, Bifidobacterium bifidum, Lactobacillus iners, Streptococcus species, and Lactobacillus salivarius increased significantly in patients with BD. Relative abundance of Megamonas hypermegale, Butyrivibrio species, Streptococcus infantis, and Filifactor species increased significantly in normal individuals compared with BD patients. In the functional annotation analysis by PICRUSt, we found prevalent gene functions of the pentose phosphate pathway and the inosine monophosphate biosynthesis in patients with BD. The data suggested that BD gut microbes altered nucleic acid and fatty acid synthesis.

CONCLUSIONS

These compositional and functional alterations of gut microbes may accompany unfavorable molecular exchanges between intestinal immunocompetent cells and gut microbes, and these interactions may have an association with the immune aberration in patients with BD.

Propionate-producing bacteria in the intestine may associate with skewed responses of IL10-producing regulatory T cells in patients with relapsing polychondritis

Relapsing polychondritis (RP) is an inflammatory disease of unknown causes, characterized by recurrent inflammation in cartilaginous tissues of the whole body. Recently, researchers have reported that, in mouse experiments, altered gut microbe-dependent T cell differentiation occurred in gut associated lymphoid tissues. Here, we investigated whether gut microbe alteration existed, and if so, the alteration affected peripheral T cell differentiation in patients with RP. In an analysis of gut microbiota, we found increased annotated species numbers in RP patients compared with normal individuals. In the RP gut microbiota, we observed several predominant species, namely Veillonella parvula, Bacteroides eggerthii, Bacteroides fragilis, Ruminococcus bromii, and Eubacterium dolichum, all species of which were reported to associate with propionate production in human intestine. Propionate is a short-chain fatty acid and is suggested to associate with interleukin (IL)10-producing regulatory T (Treg) cell differentiation in gut associated lymphoid tissues. IL10 gene expressions were moderately higher in freshly isolated peripheral blood mononuclear cells (PBMC) of RP patients than those of normal individuals. Six hours after the initiation of the cell culture, regardless of the presence and absence of mitogen stimulation, IL10 gene expressions were significantly lower in RP patients than those in normal individuals. It is well known that PBMC of patients with autoimmune and inflammatory diseases show hyporesponsiveness to mitogen stimulation. We suggest that, in RP patients, continuous stimulation of intestinal T cells by excessive propionate leads to the spontaneous IL10 production and a subsequent refractory period of T cells in patients with RP. The hyporesponsiveness of Treg cells upon activation may associate with inflammatory cytokine production of PBMC and subsequently relate to chondritis in RP patients.

Neuronal Cell Sheets of Cortical Motor Neuron Phenotype Derived from Human iPSCs

Transplantation of stem cells that differentiate into more mature neural cells brings about functional improvement in preclinical studies of stroke. Previous transplant approaches in the diseased brain utilized injection of the cells in a cell suspension. In addition, neural stem cells were preferentially used for grafting. However, these cells had no specific relationship to the damaged tissue of stroke and brain injury patients. The injection of cells in a suspension destroyed the cell–cell interactions that are suggested to be important for promoting functional integrity of cortical motor neurons. In order to obtain suitable cell types for grafting in patients with stroke and brain damage, a protocol was modified for differentiating human induced pluripotent stem cells from cells phenotypically related to cortical motor neurons. Moreover, cell sheet technology was applied to neural cell transplantation, as maintaining the cell–cell communications is regarded important for the repair of host brain architecture. Accordingly, neuronal cell sheets that were positive Forebrain Embryonic Zinc Finger (Fez) family zinc finger 2 (FEZF2), COUP-TF-interacting protein 2, insulin-like growth factor–binding protein 4 (IGFBP4), cysteine-rich motor neuron 1 protein precursor (CRIM1), and forkhead box p2 (FOXP2) were developed. These markers are associated with cortical motoneurons that are appropriate for the transplant location in the lesions. The sheets allowed preservation of cell–cell interactions shown by synapsin1 staining after transplantation to damaged mouse brains. The sheet transplantation brought about partial structural restoration and the improvement of motor functions in hemiplegic mice. Collectively, the novel neuronal cell sheets were transplanted into damaged motor cortices; the cell sheets maintained cell–cell interactions and improved the motor functions in the hemiplegic model mice. The motoneuron cell sheets are possibly applicable for stroke patients and patients with brain damage by using patient-specific induced pluripotent stem cells.

Novel reuterin-related compounds suppress odour by periodontopathic bacteria

OBJECTIVE

Halitosis is caused by volatile sulphur compounds including methyl mercaptan (CH₃ SH) in the oral cavity and is a serious problem that limits interpersonal social communication. The aim of study was to evaluate the effects of reuterin-related compounds (RRCs) on halitosis-related periodontopathic bacteria in vitro.

MATERIALS AND METHODS

RRC-01, RRC-02 and RRC-03 (32 and 64 μg ml^-1 ) in culture media containing Fusobacterium nucleatum JCM8523 and Porphyromonas gingivalis ATCC33277 were used. The effects of RRCs on CH₃ SH production and detectable odour by F. nucleatum and P. gingivalis were examined by CH₃ SH production assay and organoleptic test, respectively. The number of bacterial cells was also measured using an ATP assay. In P. gingivalis treated with RRCs, the expression of mgl gene, which is responsible for CH₃ SH production, was examined by qRT-PCR.

RESULTS

CH₃ SH production and the score of detectable odour from F. nucleatum and P. gingivalis culture media containing RRCs were significantly lower than that without RRCs (P < 0.05). The expression of mgl gene in P. gingivalis was significantly downregulated by RRC-01 (P < 0.01), but not by RRC-02 or RRC-03.

CONCLUSIONS

RRCs are potent oral care products for preventing halitosis via reducing CH₃ SH production.

Developmental Properties of the Hertwig’s Epithelial Root Sheath in Mice

Hertwig’s epithelial root sheath (HERS) plays an important role in tooth root formation. In this study, we examined root formation of the first molar in mice, focusing on cell proliferation, cell death, cell migration, and the expression patterns of the signaling molecules, including glycoproteins and proteoglycans between PN8 and PN26. The number of HERS cells decreased during root formation, although HERS retained total length until PN15. The migration of HERS cells did not occur during root formation. Moreover, the immunopositive reaction of laminin beta-3 and syndecan-1 in HERS indicates that both cell adhesion and cell proliferation are essential for HERS development. Bmp-2, Bmp-4, and Msx-2 were expressed in HERS cells during root formation. We also developed an in vitro culture system for investigating the periodontium and suggest that this system provides an excellent vehicle for full exploration, and hence improved understanding, of the development and regeneration of the periodontium. Together, our results provide a comprehensive model describing the morphogenesis of early root development in vertebrates.

Bifidobacteria Abundance-Featured Gut Microbiota Compositional Change in Patients with Behcet's Disease

Gut microbiota compositional alteration may have an association with immune dysfunction in patients with Behcet’s disease (BD). We conducted a fecal metagenomic analysis of BD patients. We analyzed fecal microbiota obtained from 12 patients with BD and 12 normal individuals by sequencing of 16S ribosomal RNA gene. We compared the relative abundance of bacterial taxa. Direct comparison of the relative abundance of bacterial taxa demonstrated that the genera Bifidobacterium and Eggerthella increased significantly and the genera Megamonas and Prevotella decreased significantly in BD patients compared with normal individuals. A linear discriminant analysis of bacterial taxa showed that the phylum Actinobacteria, including Bifidobacterium, and the family Lactobacillaceae exhibited larger positive effect sizes than other bacteria in patients with BD. The phylum Firmicutes and the class Clostridia had large effect sizes in normal individuals. There was no significant difference in annotated species numbers (as numbers of operational taxonomic unit; OTU) and bacterial diversity of each sample (alpha diversity) between BD patients and normal individuals. We next assigned each sample to a position using three axes by principal coordinates analysis of the OTU table. The two groups had a significant distance as beta diversity in the 3-axis space. Fecal sIgA concentrations increased significantly in BD patients but did not correlate with any bacterial taxonomic abundance. These data suggest that the compositional changes of gut microbes may be one type of dysbiosis (unfavorable microbiota alteration) in patients with BD. The dysbiosis may have an association with the pathophysiology of BD.

Cellular and molecular mechanisms of the restoration of human APP transgenic mouse cognitive dysfunction after transplant of human iPS cell-derived neural cells

Cholinergic neuronal loss is a common finding in patients with Alzheimer's disease (AD) and AD model mice. We previously transplanted neurons derived from human induced pluripotent stem (iPS) cells into the hippocampus of human amyloid precursor protein transgenic AD model mice. In the present study, we examined the cellular and molecular mechanisms involved in the alleviation of cognitive dysfunction in transplanted mice. After transplant, mice showed improvement in cognitive function, confirming our previous findings. Human choline acetyltransferase (ChAT)-positive cholinergic neurons were distributed throughout the cortex of the grafted mice. Human and mouse ChAT-positive neurons and alpha7 nicotinic acetylcholine receptor (α7nAChR)-positive neurons were significantly increased in the cortex and hippocampus of the grafted mice compared with the vehicle-injected mice. In addition, human and mouse vesicular GABA transporter (VGAT)-positive neurons were located mainly in the hippocampus and, though the number was small, human VGAT-positive neurons were observed in the cortex. In the grafted mouse cortex, the number of GABA receptor (GABAR)-positive neurons of both human origin and mouse origin were significantly increased compared with those in the vehicle-injected mouse cortex. The α7nAChR-positive and GABAR-positive neurons expressed phosphorylated Akt and c-fos in the cortex, suggesting that these receptor-expressing neurons were possibly activated by the neurotransmitters secreted from the grafted neurons. Collectively, the grafted and host neurons may form positive feedback loops via neurotransmitter secretion in both the cerebral cortex and hippocampus, leading to alleviation of cognitive dysfunction in dementia model mice.

Salvage chemoradiotherapy for locally advanced esophageal carcinomas

'Salvage chemoradiotherapy (CRT)' was introduced in 2005 to treat thoracic esophageal carcinomas deemed unresectable based on the intraoperative findings. The therapeutic concept is as follows: the surgical plan is changed to an operation that aims to achieve curability by the subsequent definitive CRT. For this purpose, the invading tumor is resected as much as possible, and systematic lymph node dissection is performed except for in the area around the bilateral recurrent nerves. The definitive CRT should be started as soon as possible and should be performed as planned. We hypothesized that this treatment would be feasible and provide good clinical effects. We herein verified this hypothesis. Twenty-seven patients who received salvage CRT were enrolled in the study, and their clinical course, therapeutic response, and prognosis were evaluated. The patients who had poor oral intake because of esophageal stenosis were able to eat solid food soon after the operation. The radiation field could be narrowed after surgery, and this might have contributed to the high rate of finishing the definitive CRT as planned. As a result, the overall response rate was 74.1%, and 48.1% of the patients had a complete response. No patient experienced fistula formation. The 1-, 3-, and 5-year overall survival rates were 66.5%, 35.2%, and 35.2%, respectively. Salvage CRT had clinical benefits, such as the fact that patients became able to have oral intake, that fistula formation could be prevented, that the adverse events associated with the definitive CRT could be reduced, and that prognosis of the patients was satisfactory. Although the rate of recurrent nerve paralysis was relatively high even after the suspension of aggressive bilateral recurrent nerve lymph node dissection, and the rate of the progressive disease after the definitive CRT was high, salvage CRT appears to provide some advantages for the patients who would otherwise not have other treatment options following a non-curative and residual operation.

Possible association of proinflammatory cytokines including IL1β and TNFα with enhanced Th17 cell differentiation in patients with Behcet's disease

We have reported that helper T type 17 (Th17) cells increased in patients with Behcet's disease (BD). It remains obscure how Th17 cells increase in the patients. We here analyzed whether T cells preferentially differentiate into Th17 cells in response to various inflammatory cytokines in patients with BD. Exogenous interleukin (IL)23 sustained the higher Th17 cell frequencies of CD4+CD45RO+ T cells after a 2-day culture in vitro in patients with BD, whereas the T cell subpopulation of normal individuals did not respond to IL23 to sustain/increase Th17 cell frequencies. IL23 receptor positive cell frequencies in freshly isolated BD CD4+CD45RO+ T cells correlated with Th17 cell frequencies assessed by intracellular cytokine staining. After a 2-day culture with IL23, BD CD4+ T cells retained the correlation between IL23 receptor expression level and extent of IL17 secretion (as indicated by Th17 cell frequencies), whereas such correlation was not noted in normal individuals. IL23 signals with its receptor were thus suggested to induce IL17 secretion (Th17 cell frequencies) in a short-time culture in patients with BD. We cultured CD4+CD45RO- T cells for 11 days with various inflammatory cytokines to study which cytokine associated with the enhanced Th17 frequencies in the patients. IL17 production by CD4+CD45RO- T cells of BD patients increased significantly by the supplementation of IL1β and tumor necrosis factor (TNF)α, in addition to IL23, compared with that of normal individuals. These results suggest that proinflammatory cytokines, such as IL1β, TNFα, and IL23, may associate with the expansion of Th17 cells in patients with BD. This study was registered with the University Hospital Medical Information Network-Clinical Trials Registry (UMIN000003806).

Restoration of spatial memory dysfunction of human APP transgenic mice by transplantation of neuronal precursors derived from human iPS cells

PDGF promoter driven amyloid precursor protein (PDAPP) transgenic mice were accompanied by age dependent amyloid β deposition and progressive spatial memory dysfunction which emerges within a few months of age. We conducted transplantation of neuronal precursors of cholinergic neuron phenotype which were derived from human iPS (hiPS) cells into bilateral hippocampus of PDAPP mice. We first generated neuronal precursors with cholinergic neuron phenotype from hiPS cells by culturing them with retinoic acid (RA), sonic hedgehog (SHH) and noggin-Fc (NOG). Spatial memory function of PDAPP mice was significantly impaired compared to that of nontransgenic littermates at age 8 weeks. After neuronal precursor transplantation, subsequent memory dysfunction of PDAPP mice was significantly improved, compared to that of vehicle injected PDAPP mice. We observed choline acetyltransferase (ChAT) positive cholinergic human neurons and vesicle GABA transporter (VGAT) positive GABAergic human neurons in PDAPP mouse hippocampus 45 days after the transplantation. Neuronal precursors with cholinergic neuron phenotype derived from hiPS cells survived in PDAPP mouse hippocampus and their spatial memory loss was improved. hiPS cells may become applicable for the treatment of patients with dementia.

CD72 Stimulation Modulates Anti-IgM Induced Apoptotic Signaling through the Pathway of NF-κB, c-Myc and p27Kip1

Engagement of mIgM induces G1 arrest and apoptosis in immature B cells. The biochemical mechanism(s) regulating the cell death process are poorly understood. Cross-linking of CD72 (a B cell co-receptor) with anti-CD72 antibody was shown to protect B cells from apoptosis. We investigated the molecular mechanism involved in apoptosis preventing signaling mediated by CD72 ligation using a derivative (WEHIdelta) of the WEHI231 cell line which is representative of immature B cells. Apoptotic WEHIdelta cells following cross-linking of mIgM demonstrate a dramatic loss of c-Myc protein after transient up-regulation. In contrast, pre-ligation of CD72 was able to sustain c-Myc expression after transient up-regulation. Cross-linking of mIgM of WEHIdelta cells causes accumulation of the Cdk inhibitor, p27(Kip1). CD72 pre-ligation was shown to inhibit the accumulation of p27(Kip1) protein. Moreover, NF-kappaB activity was not suppressed in WEHIdelta cells after mIgM cross-linking when the cells were pre-treated with anti-CD72 antibody. These results strongly suggest that the apoptosis preventing signal evoked by CD72 ligation is delivered through the pathway of NF-kappaB, c-Myc, p27(Kip1) and cyclin.

Detection of antiferromagnetic ordering in heavily doped LaFeAsO(1-x)H(x) pnictide superconductors using nuclear-magnetic-resonance techniques

We studied double superconducting (SC) domes in LaFeAsO(1-x)H(x) by using 75As and 1H nuclear-magnetic-resonance techniques and unexpectedly discovered that a new antiferromagnetic (AF) phase follows the double SC domes on further H doping, forming a symmetric alignment of AF and SC phases in the electronic phase diagram. We demonstrated that the new AF ordering originates from the nesting between electron pockets, unlike the nesting between electron and hole pockets, as seen in the majority of undoped pnictides. The new AF ordering is derived from the features common to high-Tc pnictides; however, it has not been reported so far for other high-Tc pnictides because of their poor electron doping capability.

Cell dynamics in cervical loop epithelium during transition from crown to root: implications for Hertwig's epithelial root sheath formation

BACKGROUND AND OBJECTIVE

Some clinical cases of hypoplastic tooth root are congenital. Because the formation of Hertwig's epithelial root sheath (HERS) is an important event for root development and growth, we have considered that understanding the HERS developmental mechanism contributes to elucidate the causal factors of the disease. To find integrant factors and phenomenon for HERS development and growth, we studied the proliferation and mobility of the cervical loop (CL).

MATERIAL AND METHODS

We observed the cell movement of CL by the DiI labeling and organ culture system. To examine cell proliferation, we carried out immunostaining of CL and HERS using anti-Ki67 antibody. Cell motility in CL was observed by tooth germ slice organ culture using green fluorescent protein mouse. We also examined the expression of paxillin associated with cell movement.

RESULTS

Imaging using DiI labeling showed that, at the apex of CL, the epithelium elongated in tandem with the growth of outer enamel epithelium (OEE). Cell proliferation assay using Ki67 immunostaining showed that OEE divided more actively than inner enamel epithelium (IEE) at the onset of HERS formation. Live imaging suggested that mobility of the OEE and cells in the apex of CL were more active than in IEE. The expression of paxillin was observed strongly in OEE and the apex of CL.

CONCLUSION

The more active growth and movement of OEE cells contributed to HERS formation after reduction of the growth of IEE. The expression pattern of paxillin was involved in the active movement of OEE and HERS. The results will contribute to understand the HERS formation mechanism and elucidate the cause of anomaly root.

Excessive CD4+ T cells co-expressing interleukin-17 and interferon-γ in patients with Behçet's disease

Excessive T helper type 1 (Th1) cell activity has been reported in Behçet's disease (BD). Recently, association of Th17 cells with certain autoimmune diseases was reported, and we thus investigated circulating Th17 cells in BD. CD4(+) CD45RO(-) (naive) T cells were cultured with Th0-, Th1-, Th2- and Th17-related cytokines and antibodies, and their mRNA was studied by real-time polymerase chain reaction (PCR). When naive CD4(+) T cells were cultured with Th1- and Th17-related cytokines, interferon (IFN)-γ mRNA and interleukin (IL)-17 mRNA were up-regulated, respectively, in BD patients. Naive CD4(+) T cells cultured in a Th17 cell-inducing condition expressed IL-23 receptor (IL-23R) mRNA excessively. IL-17 mRNA expression was induced only when naive CD4(+) T cells were cultured in the presence of IL-23. CD4(+) T cells cultured with Th17 cytokines expressed excessive RAR-related orphan receptor C (RORC) mRNA. Using intracellular cytokine staining, we found that CD45RO(+) (memory) CD4(+) T cells producing IL-17 and IFN-γ simultaneously were increased significantly. Memory CD4(+) T cells producing IFN-γ but not IL-17 decreased profoundly in BD patients. CD4(+) T cells producing IL-17 and IFN-γ simultaneously were found in BD skin lesions. Collectively, we found excessive CD4(+) T cells producing IL-17 and IFN-γ (Th1/Th17) cells in patients with BD, and possible involvement of IL-23/IL-23R pathway for the appearance of excessive Th1/Th17 cells.

Skewed TGFβ/Smad signalling pathway in T cells in patients with Behçet's disease

OBJECTIVES

Behçet's disease (BD) is a multi-systemic inflammatory disease, characterised by recurrent oral aphthosis, genital ulcers, skin lesions and uveitis. We have reported excessive Th1 cell activity in patients with BD. More recently, Th17 cells were suggested to associate with several autoimmune diseases. This study was designed to investigate the role of Th17 related cytokines and signalling molecules in patients with BD.

METHODS

We examined mRNA expressions of Th1 and Th17 related cytokines and related signalling molecules in PBMC of 12 patients with BD and 14 normal controls (NC) using quantitative RT-PCR. We studied expressions of the Th17 related cytokines in other four BD patients' skin lesions by immunofluorescence.

RESULTS

Major Th17 related cytokines were not detected in unstimulated PBMC in patients with BD. After stimulation, mRNA expressions of TGFβ receptor type 1, IL-12 receptor β2 and suppressor of cytokine signalling protein (SOCS) 1 on PBMC were significantly enhanced in patients with BD, as compared with NC (p<0.05). mRNA expression of RORC, a key transcription factor for Th17 cell differentiation, was comparable between BD and NC. CD4+ T cells infiltrating into BD skin lesion expressed TGFβ1 much more than those infiltrating into non-Behçet's disease erythema nodosum.

CONCLUSIONS

These findings suggest that TGFβ/Smad signalling pathway of T cells is overactive in patients with BD.

Hepatocyte growth factor stimulates root growth during the development of mouse molar teeth

BACKGROUND AND OBJECTIVE

It is well known that tooth root formation is initiated by the development of Hertwig's epithelial root sheath (HERS). However, relatively little is known about the regulatory mechanisms involved in root development. As hepatocyte growth factor (HGF) is one of the mediators of epithelial-mesenchymal interactions in rodent tooth, the objective of this study was to examine the effects of HGF on the root development of mouse molars.

MATERIAL AND METHODS

The HERS of mouse molars and HERS01a, a cell line originated from HERS, were used in this study. For detection of HGF receptors in vivo and in vitro, we used immunochemical procedures. Root development was assessed by implanting molar tooth germs along with HGF-soaked beads into kidney capsules, by counting cell numbers in HERS01a cell cultures and by performing a 5'-bromo-2'-deoxyuridine (BrdU) assay in an organ-culture system.

RESULTS

HGF receptors were expressed in the enamel epithelium of molar germs as well as in HERS cells. HGF stimulated root development in the transplanted tooth germs, the proliferation of HERS01a cells in culture and HERS elongation in the organ-culture system. Examination using BrdU revealed that cell proliferation in HERS was increased by treatment with HGF, especially that in the outer layer of HERS. This effect was down-regulated when antibody against HGF receptor was present in the culture medium.

CONCLUSION

Our results raise the possibility that HGF signaling controls root formation via the development of HERS. This study is the first to show that HGF is one of the stimulators of root development.

Genomic analysis of RAE-1 genes (35.30)

NKG2D is an activating receptor on NK cells and activated CD8 T cells that has been implicated in tumor immunity, viral immunity and autoimmunity. The ligands of NKG2D are tightly regulated stress-inducible molecules, whose expression is triggered by transformation or infection. In mice, these NKG2D ligands include the retinoic acid early inducible-1 (RAE-1) proteins. However, the mechanisms of transcriptional regulation in RAE-1 genes are poorly understood. We examined what transcription factors regulate RAE-1 expression. We found that RAE-1 delta has six exons and RAE-1 epsilon has seven exons. We isolated genomic DNAs of upstream from exon one which are thought of RAE-1 promoters in RAE-1 delta or RAE-1 epsilon. We found that consensus sequences of several transcription factors are present in RAE promoters. Therefore, these transcription factors may regulate RAE-1 expressions.

This work is supported by Grants-in Aid for Science Research from the Ministries of Education, Culture, Sports, Science, and Technology of Japan, Grants-in Aid for Science Research from the Ministriesof Health, Labor, and Welfare of Japan, Human Frontier Science Program CDA, The Mitsubishi Foundation, The Sumitomo Foundation, Takeda Science Foundation and Uehara Memorial Foundation.

Ligand-of-Numb protein X is an endocytic scaffold for junctional adhesion molecule 4

Junctional adhesion molecule 4 (JAM4) is a cell adhesion molecule that interacts with a tight junction protein, membrane-associated guanylate kinase inverted 1 (MAGI-1). Our previous studies suggest that JAM4 is implicated in the regulation of paracellular permeability and the signalings of hepatocyte growth factor. In this study, we performed yeast two-hybrid screening to search for an unidentified JAM4-binding protein and obtained one isoform of Ligand-of-Numb protein X1 (LNX1), LNXp70, that is an interactor of Numb. Ligand-of-Numb protein X1 is expressed in kidney glomeruli and intestinal epithelial cells, where JAM4 is also detected. Immunoprecipitation from kidney lysates supports the in vivo interaction of proteins. Biochemical studies reveal that JAM4 directly binds the second PDZ domain of LNX1 through its carboxyl terminus. Junctional adhesion molecule 4, LNX1 and Numb form a tripartite complex in vitro and are partially colocalized in heterologous cells. Ligand-of-Numb protein X1 facilitates endocytosis of JAM4 and is involved in transforming growth factor beta -induced redistribution of JAM4 in mammary epithelial cells. Experiments using dominant-negative constructs and RNA interference insure that Numb is necessary for the LNX1-mediated endocytosis of JAM4. All these findings indicate that LNX1 provides an endocytic scaffold for JAM4 that is implicated in the reorganization of cell junctions.

A novel avian homologue of CD72, chB1r, down modulates BCR-mediated activation signals

The avian B cell differentiation antigen chB1 is a C-type lectin membrane protein most homologous to mammalian CD72. Here, we report a new chB1-related gene, chB1r, that is located 18 kb away the chB1 gene. The cytoplasmic domain of chB1r protein contains two immunoreceptor tyrosine-based inhibitory motifs (ITIMs: ITIM1 and 2), which are identical to those found in CD72, whereas chB1 lacks the second ITIM2. Although chB1 expression is restricted to the bursa and an immature B cell line, chB1r is highly expressed in the bursa, spleen and both immature and mature B cell lines, a pattern that parallels CD72 expression. SHP-1 and Grb2 interact with phosphorylated tyrosine residues within chB1r ITIM1 and ITIM2, respectively. By contrast, ITIM1 of chB1 does not interact with SHP-1. Functional characterization using chB1r/chB1 double-deficient DT40 B cells demonstrated that ITIM1 in chB1r transduces a negative signal for BCR-mediated nuclear factor of activated T cells (NF-AT) activation and that ITIM2 attenuates this negative signal. This study has established chB1r as the genuine avian homologue of mammalian CD72, and revealed an opposing role for the two ITIMs through binding with SHP-1 and Grb2 for regulation of BCR-mediated NF-AT activation.

Targeting of MIST to Src-family kinases via SKAP55-SLAP-130 adaptor complex in mast cells

MIST (mast cell immunoreceptor signal transducer; also termed Clnk) is an adaptor protein structurally related to SLP-76-family hematopoietic cell-specific adaptor proteins. We demonstrate here that two major MIST-associated phosphoproteins expressed in mast cell lines are SLAP-130 and SKAP55, adaptors known to interact with the Src-homology (SH) 2 domain of Src-family protein tyrosine kinases (PTKs). MIST directly associated with SLAP-130 via its SH2 domain, and collaboration of SLAP-130 with SKAP55 was required for the recruitment of MIST to Lyn. Furthermore, MIST was preferentially recruited to Fyn rather than Lyn, which is regulated by higher affinity binding of SLAP-130 and SKAP55 with the Fyn-SH2 domain than the Lyn-SH2 domain. Our results suggest that the MIST-SLAP-130-SKAP55 adaptor complex functions downstream of high-affinity IgE receptor-associated Src-PTKs in mast cells.

Asymmetric transport due to spin injection into a Kondo alloy

Spin injection is found to have a significant effect on the transport properties of the Kondo alloy Cu(Fe). When a spin-polarized electron current flows from Co into Cu(Fe) wires through the Co/Cu(Fe) interface, the resistivity of the Cu(Fe) wire is suppressed near the interface, as distinct from the ordinary logarithmic increase in the resistivity at low temperatures. For the opposite current direction, no significant changes are observed. The asymmetry of the resistivity with respect to the current direction decays with a characteristic length of 1.5+/-0.4 microm at 2.5 K as the distance from the interface is increased. Possible mechanisms for the asymmetry are discussed.

Maturational change of parallel auditory processing in school-aged children revealed by simultaneous recording of magnetic and electric cortical responses

OBJECTIVES

To elucidate the maturational change of cortical auditory processing, we analyzed simultaneously recorded auditory evoked potentials (AEPs) and magnetic fields (AEFs) in school-aged children.

METHODS

Simultaneous recording of AEP and AEF were performed in 32 healthy children of age ranging from 6 to 14 years and 10 adults. Tone bursts of 1 kHz were presented to the left and right ears alternately with 3 different within-ear stimulus onset asynchronies (SOAs) (1.6, 3.0 and 5.0 s for each ear) under attention-distracted condition.

RESULTS

All subjects showed clear N100 and N100m peaks under the longest SOA condition (5.0 s). Under the shortest SOA condition (1.6 s), 4 out of 19 subjects under 12 years (21%) failed to show the N100m component. By contrast, N250 and N250m were observed in the majority of children (29/32: 91%) while those were detected in only 4 out of 10 adults (40%). The spatial distribution of N100 in children under 9 years differed from that in older subjects, whereas the dipole orientation of N100m was constant among age groups, suggesting that radially oriented sources might make additional contribution to the generation of N100 in early childhood. N250 was significantly larger in children than in adults. The strength of N250 was suppressed with longer SOAs, whereas that of N100 was enhanced. The dipole of N250m was located around Heschl's gyrus on the superior temporal plane which was significantly medial, anterior and inferior to that of N100m.

CONCLUSIONS

Dissociation of maturational change between the tangential and radial components of N100 suggests that auditory processing at around 100 ms consists of multiple parallel pathways which mature independently. Furthermore, a negative peak at around 250 ms specifically seen in children has different generators from N100 and might represent a special auditory processing which takes an active part until acquisition of the efficient cortical networks of the adult brain.

A mechanism for mercury oxidation in coat-derived exhausts

This paper evaluates an elementary reaction mechanism for Hg0 oxidation in coal-derived exhausts consisting of a previously formulated homogeneous mechanism with 102 steps and a new three-step heterogeneous mechanism for unburned carbon (UBC) particles. Model predictions were evaluated with the extents of Hg oxidation monitored in the exhausts from a pilot-scale coal flame fired with five different coals. Exhaust conditions in the tests were very similar to those in full-scale systems. The predictions were quantitatively consistent with the reported coal-quality impacts over the full range of residence times. The role of Cl atoms in the homogeneous mechanism is hereby supplanted with carbon sites that have been chlorinated by HCl. The large storage capacity of carbon for Cl provided a source of Cl for Hg oxidation over a broad temperature range, so initiation was not problematic. Super-equilibrium levels of Cl atoms were not required, so Hg was predicted to oxidize in systems with realistic quench rates. Whereas many fundamental aspects of the heterogeneous chemistry remain uncertain, the information needed to characterize Hg oxidation in coal-derived exhausts is now evident: complete gas compositions (CO, hydrocarbons, H2O, O2 NOx, SOx), UBC properties (size, total surface area), and the ash partitioning throughout the exhaust system are required.

Discrepancies in dietary intakes and plasma concentrations of fatty acids according to age among Japanese female dietitians

OBJECTIVE

To clarify the influences of age on dietary intakes and plasma concentrations of fatty acids (FAs) in Japanese female dietitians.

SUBJECTS AND METHODS

In autumn 1996, we estimated dietary FA intakes based on 7 day weighed diet records and analyzed plasma FA concentrations in 79 healthy Japanese female dietitians, and investigated their relationships with age, dividing into three age groups (young (32-42 y), middle-aged (43-50 y) and elderly (51-66 y)).

RESULTS

Dietary intakes of total FA, saturated FAs, monounsaturated FAs, n-3 polyunsaturated FAs (PUFAs) and alpha-linolenic acid (18:3n-3) were significantly highest in the middle-aged group, and lowest in the elderly. Similar trends were observed for dietary intakes of n-6 PUFAs and linoleic acid (18:2n-6), but there were no differences with regard to eicosapentaenoic acid (EPA; 20:5n-3), docosahexaenoic acid (DHA; 22:6n-3) and n-3 highly unsaturated FAs (HUFAs=EPA+22:5n-3+DHA). On the other hand, plasma concentrations of all FAs except for arachidonic acid (20:4n-6) demonstrated positive correlations with age. Moreover, plasma concentrations of EPA in all age groups, DHA in the elderly and n-3 HUFAs in the middle-aged and the elderly were all positively correlated with dietary intakes.

CONCLUSIONS

We should take into account the influence of age on dietary habit and lipid metabolism when interpreting associations between dietary FA intakes and plasma FA concentrations.

Optical imaging of excitation propagation evoked by stimulation to the trigeminal caudalis

The present study reports on a characteristic spatio-temporal propagation of differential fluorescent images in the rat brain stem slice by a high-speed optical imaging technique. Coronal or sagittal slices were stained with a voltage-sensitive dye RH-414, and the superficial layer of the trigeminal caudalis (Vc) was then electrically stimulated. The marginal layer and substantia gelatinosa showed larger rostrocaudal excitation than coronal, despite a lack of tract stimulation expansion in either direction. A perfusion of 0.5 micromol/l TTX, not 10 micromol/l CNQX suppressed these propagations. These findings suggest that the superficial layer of Vc has spatial differences in neuronal excitation propagation, as evidenced by morphological observations that dendrites in the superficial layers extend in the rostrocaudal direction.

Vasospastic total occlusion at the left main tract in a single coronary artery

A 64-year-old man was admitted to hospital under the suspicion of unstable angina pectoris. Coronary angiography showed that he has a single coronary artery originating from the right coronary artery (RCA) without significant fixed stenosis. Acetylcholine was superselectively infused into the left main coronary artery (LMCA), and confirmed the coronary vasospastic occlusion associated with chest pain and elevation of the ST-segment in the precordial leads. This is the first report of the induction of a totally occlusive spasm of the LMCA of a patient with a RCA type single coronary artery, and this case suggests that spasm of the aberrant coronary artery is a potential mechanism for sudden death in patients with a single coronary artery.

Dioxin and fly ash free incineration by ash pelletization and reburning

Dioxins (DXNs) in municipal waste incinerator fly ash were effectively reduced by pelletizing the mixture of ash, cement, and sodium phosphate and reburning the pellets in a laboratory scale bubbling fluidized bed (BFB) furnace. Three types of pellets--A, B and C, of various sizes and compositions were used in the experiments. The efficiency of DXN reduction in the pellet matrix was proportional to the incineration time, temperature, and degree of pellet incineration. At 700 degrees C and incineration time sufficient for a complete burnout, the efficiency of DXN reduction in the pellets of type A and C was found to be 99.9% and 99.7%, respectively. Correspondingly, the DXN concentration in the pellets decreased from 862 ng TEQ/kg to 0.9 ng TEQ/kg for pellets A and 2.2 ng TEQ/kg for pellets C. The residual concentration of coplanar polychlorinated biphenyls (coplanar PCBs) was below 0.2 ng TEQ/kg and 0.4 ng TEQ/kg, respectively. Assuming a tortuosity factor of tau = 3 and the reaction rate constants of 0.013 m/s (at 700 degrees C) and 0.025 m/s (at 800 degrees C), the experimental pellet incineration times were reasonably predicted by using the shrinking core model. Possible DXN evaporation from the pellets was also studied. The amount of DXNs in the flue gas captured by an impinger trap was less than 3% when the reactor was operated at 700 and 800 degrees C. The described method of fly ash pelletization and reburning seems to be a relatively easy and inexpensive way to reduce both the emission of DXNs and the amount of fly ash.

Kinetic modeling of homogeneous mercury oxidation: the importance of NO and H2O in predicting oxidation in coal-derived systems

This paper develops and evaluates an elementary reaction mechanism for homogeneous Hg0 oxidation that accounts for major interactions among Cl-species and other pollutants in coal-derived exhausts. Most importantly, interactions among NO and Cl-species were found to exert a strong and previously unrecognized impact on homogeneous Hg0 oxidation under some but not all conditions. The proposed oxidation mechanism is subjected to quantitative evaluations against all the available laboratory datasets that characterize homogeneous Hg0 oxidation when HCl is the primary chlorinated species. The simulations depict the reported extents of oxidation for broad ranges of HCl and temperature within useful quantitative tolerances without any heuristic parameter adjustments. The predicted pool of Cl-atoms was found to be governed by the chemistries of moist CO oxidation, Cl-species transformations, and NO production. However, an artificial initiation scheme was needed to depict the temperature dependence observed in one set of literature data. This indicates that either the kinetic mechanisms are incomplete or that heterogeneous initiation came into play under these test conditions. The evaluations further show that Hg oxidation is primarily through a Cl atom recycle process, with Cl and Cl2 concentrations both playing an important role. Oxygen weakly promotes homogeneous Hg oxidation, whereas moisture is a stronger inhibitor. NO can promote or inhibit homogeneous Hg oxidation, depending on its concentration. In the presence of NO, extents of Hg oxidation increased for progressively faster quenching. Conversely, without NO, extents of oxidation diminished for faster quenching.

Relative validity of a semi-quantitative food frequency questionnaire versus 28 day weighed diet records in Japanese female dietitians

OBJECTIVE

To assess the relative validity of a semi-quantitative food frequency questionnaire (SQFFQ) against 28 day weighed diet records (WDRs).

SUBJECTS AND METHODS

The SQFFQ was administered to 106 (21 male and 85 female) Japanese dietitians in Aichi Prefecture in autumn, 1996 and four-season consecutive 7 day WDRs were carried out during 1996-1997. We evaluated validity of intakes of 15 foods and 31 macro- and micro-nutrients based on the SQFFQ against those according to 28 day WDRs among 79 Japanese female dietitians.

RESULTS

Mean daily intakes of selected foods and nutrients determined by the SQFFQ were generally equivalent to those measured by 28 day WDRs. Pearson's de-attenuated correlation coefficients (CCs) with log-transformation and energy-adjustment between intakes of selected foods and nutrients quantified by the SQFFQ and 28 day WDRs (minimum-median-maximum) ranged from 0.17 (beverages)-0.52 to 0.74 (rice), and Spearman's rank CCs with energy-adjustment ranged from 0.28 (confectionery)-0.42 to 0.68 (rice). Respective Pearson's CCs for intakes of nutrients were 0.28 (PUFAs)-0.51 to 0.73 (magnesium), and Spearman's rank CCs ranged from 0.23 (n-3 PUFAs)-0.45 to 0.71 (magnesium). Favorably higher agreement for intakes of foods/nutrients was achieved along with lower disagreement.

CONCLUSIONS

Satisfactorily higher relative validity was attained in Japanese female dietitians with the SQFFQ. This calibrated questionnaire seems therefore appropriate for administration to Japanese dietitians to clarify associations between diet and health/disease.

SPONSORSHIP

A grant-in-aid from the Ministry of Education, Science, Sports and Culture (06454242).

Mycobacterial cord factor, but not sulfolipid, causes depletion of NKT cells and upregulation of CD1d1 on murine macrophages

Trehalose 6,6'-dimycolate (TDM, cord factor) has frequently been used as an adjuvant to stimulate antibody production. Although it also induces cellular immunity, detailed studies about the underlying events do not exist. To determine the kinetics of TDM-specific changes promoting a T helper 1 (Th1) response, we injected mice with TDM or 2,3,6,6'-tetraacyl trehalose 2'-sulfate (SL, sulfolipid), another mycobacterial trehalose-containing glycolipid without mycolic acid. TDM, but not SL, caused a strong increase in serum interferon-gamma (IFN-gamma) levels 2 days later, accompanied by expansion of natural killer (NK) cells. Subsequent TDM effects included depletion of normal-density CD4(+) NK1.1(+) TCRalpha/beta(intermediate) cells from day 7 on, upregulation of MHC class II and CD1d1 on macrophages (peaking on day 21), and an increased proportion of Th1 cells evident after 3 weeks. TDM, but not a similar glycolipid without mycolic acid, can therefore initiate a cascade of events starting with strong release of IFN-gamma and NK cell expansion, resulting in the appearance of macrophages activated for antigen presentation. Our data therefore provide the basis for optimized immunization schedules with TDM as the adjuvant component of a Th1 vaccine.

Roles of N-terminal active cysteines and C-terminal cysteine-selenocysteine in the catalytic mechanism of mammalian thioredoxin reductase

Mammalian thioredoxin reductase [EC 1.6.4.5], a homodimeric flavoprotein, has a marked similarity to glutathione reductase. The two cysteines in the N-terminal FAD domain (-Cys59-x-x-x-x-Cys64-) and histidine (His472) are conserved between them at corresponding positions, but the mammalian thioredoxin reductase contains a C-terminal extension of selenocysteine (Sec or U) at the penultimate position and a preceding cysteine (-Gly-Cys497-Sec498-Gly). Introduction of mutations into the cloned rat thioredoxin reductase gene revealed that residues Cys59, Cys64, His472, Cys497, and Sec498, as well as the sequence of Cys497 and Sec498 were essential for thioredoxin-reducing activity. To analyze the catalytic mechanism of the mammalian thioredoxin reductase, the wild-type, U498C, U498S, C59S, and C64S were overproduced in a baculovirus/insect cell system and purified. The wild-type thioredoxin reductase produced in this system, designated as WT, was found to lack the Sec residue and to terminate at Cys497. A Sec-containing thioredoxin reductase, which was purified from COS-1 cells transfected with the wild-type cDNA, was designated as SecWT and was used as an authentic enzyme. Among mutant enzymes, only U498C retained a slight thioredoxin-reducing activity at about three orders magnitude lower than SecWT. WT, U498C, and U498S showed some 5,5'-dithiobis(2-nitrobenzoic acid)-reducing activity and transhydrogenase activity, and C59S and C64S had substantially no such activities. These data and spectral analyses of these enzymes suggest that Cys59 and Cys64 at the N-terminus, in conjunction with His472, function as primary acceptors for electrons from NADPH via FAD, and that the electrons are then transferred to Cys497-Sec498 at the C-terminus for the reduction of oxidized thioredoxin in the mammalian thioredoxin reductase.