Preparation of polymer gel dosimeters based on less toxic monomers and gellan gum.

New polymer gel dosimeters consisting of 2-hydroxyethyl methacrylate (HEMA), triethylene glycol monoethyl ether monomethacrylate (TGMEMA), polyethylene glycol 400 dimethacrylate (9G), tetrakis (hydroxymethyl) phosphonium chloride as an antioxidant, and gellan gum as a gel matrix were prepared. They were optically analyzed by measuring absorbance to evaluate a dose response. The absorbance of the polymer gel dosimeters that were exposed to (60)Co γ-rays increased with increasing dose. The dosimeters comprising HEMA and 9G showed a linear increase in absorbance in the dose range from 0 to 10 Gy. The dose response depended on the 9G concentration. For others comprising HEMA, 9G and TGMEMA, the absorbance of the polymer gel dosimeters drastically increased above a certain dose, and then leveled off up to 10 Gy. The optical variations in these polymer gel dosimeters were also induced by x-irradiation from Cyberknife radiotherapy equipment. Furthermore, the exposed region of the latter polymer gel dosimeter exhibited a thermo-responsive behavior.

Cross talk between hedgehog and epithelial-mesenchymal transition pathways in gastric pit cells and in diffuse-type gastric cancers.

We previously reported hedgehog (Hh) signal activation in the mucus-secreting pit cell of the stomach and in diffuse-type gastric cancer (GC). Epithelial-mesenchymal transition (EMT) is known to be involved in tumour malignancy. However, little is known about whether and how both signallings cooperatively act in diffuse-type GC. By microarray and reverse transcription-PCR, we investigated the expression of those Hh and EMT signalling molecules in pit cells and in diffuse-type GCs. How both signallings act cooperatively in those cells was also investigated by the treatment of an Hh-signal inhibitor and siRNAs of Hh and EMT transcriptional key regulator genes on a mouse primary culture and on human GC cell lines. Pit cells and diffuse-type GCs co-expressed many Hh and EMT signalling genes. Mesenchymal-related genes (WNT5A, CDH2, PDGFRB, EDNRA, ROBO1, ROR2, and MEF2C) were found to be activated by an EMT regulator, SIP1/ZFHX1B/ZEB2, which was a target of a primary transcriptional regulator GLI1 in Hh signal. Furthermore, we identified two cancer-specific Hh targets, ELK1 and MSX2, which have an essential role in GC cell growth. These findings suggest that the gastric pit cell exhibits mesenchymal-like gene expression, and that diffuse-type GC maintains expression through the Hh-EMT pathway. Our proposed extensive Hh-EMT signal pathway has the potential to an understanding of diffuse-type GC and to the development of new drugs.

Effects of ultrasound on the proliferation and differentiation of cementoblast lineage cells.

BACKGROUND: The purpose of this study was to investigate the effects of low-intensity pulsed ultrasound (LIPUS) stimulation on the proliferation and differentiation of cementoblast lineage cells. METHODS: An immortalized human periodontal ligament cell line (HPL) showing immature cementoblastic differentiation was used. Cultured HPL cells were subjected to LIPUS exposure (frequency = 1 MHz; pulsed 1:4; intensity = 30 mW/cm(2)) or sham exposure for 15 minutes per day. Expression levels of alkaline phosphatase (ALP), type I collagen (Col-I), runt-related gene 2 (Runx2), bone sialoprotein (BSP), osteocalcin (OCN), and osteopontin (OPN) mRNA were analyzed with real-time polymerase chain reaction analysis. Furthermore, ALP activity, collagen synthesis, and protein level of Runx2 were examined after 6 days of LIPUS exposure. RESULTS: mRNA and protein levels of ALP, Col-I, and Runx2 were significantly increased by LIPUS exposure compared to controls, whereas BSP, OCN, and OPN mRNA expression could not be detected in HPL cells, irrespective of LIPUS exposure. CONCLUSION: LIPUS enhanced ALP activity, collagen synthesis, and Runx2 expression of HPL cells, which provides important insight into the promotion of early cementoblastic differentiation of immature cementoblasts.

Adenosine A2A receptor antagonists: blockade of adenosinergic effects and T regulatory cells.

The intensity and duration of host responses are determined by protective mechanisms that control tissue injury by dampening down inflammation. Adenosine generation and consequent effects, mediated via A2A adenosine receptors (A2AR) on effector cells, play a critical role in the pathophysiological modulation of these responses in vivo. Adenosine is both released by hypoxic cells/tissues and is also generated from extracellular nucleotides by ecto-enzymes e.g. CD39 (ENTPD1) and CD73 that are expressed by the vasculature and immune cells, in particular by T regulatory cell. In general, these adenosinergic mechanisms minimize the extent of collateral damage to host tissues during the course of inflammatory reactions. However, induction of suppressive pathways might also cause escape of pathogens and permit dissemination. In addition, adenosinergic responses may inhibit immune responses while enhancing vascular angiogenic responses to malignant cells that promote tumor growth. Novel drugs that block A2AR-adenosinergic effects and/or adenosine generation have the potential to boost pathogen destruction and to selectively destroy malignant tissues. In the latter instance, future treatment modalities might include novel 'anti-adenosinergic' approaches that augment immune clearance of malignant cells and block permissive angiogenesis. This review addresses several possible pharmacological modalities to block adenosinergic pathways and speculates on their future application together with impacts on human disease.

Increase of RP105-lacking activated B cells in the peripheral blood and salivary glands in patients with Sjögren's syndrome.

OBJECTIVE: To quantify the activated B cells in the peripheral blood and salivary glands of patients with Sjögren's syndrome (SS) by analyzing the expression of RP105 molecule on the B cells. METHODS: The expression of RP105 on the peripheral blood B cells of patients with SS (19 cases) was analyzed by flow cytometry. RP105-positive and negative B cells were sorted and cultured in vitro and the amount of immunoglobulins (IgG and IgM) produced in the supernatant was measured by enzyme-linked immunosorbent assay (ELISA). Salivary gland biopsy samples from 9 SS patients were histologically evaluated and the sequential frozen sections were separately immunostained by anti-RP105 and anti-CD20 monoclonal antibodies. RESULTS: A significantly higher proportion of peripheral blood RP105-negative B cells was found in SS patients than in healthy individuals. RP105-negative, but not positive, B cells from SS patients were capable of producing IgG and IgM spontaneously in vitro, which was enhanced by the addition of Staphylococcus aureus Cowan I strain (SAC) or IL-6. Salivary glands from 2 of 9 SS patients were found to have lymphoid follicles whose germinal centers consisted of RP105-negative B cells. Moreover, a larger proportion of B cells extensively infiltrating the area other than lymphoid follicles was also RP105-negative. CONCLUSION: RP105-negative B cells, a subset of highly activated and well differentiated B cells, which are increased in number in the peripheral blood and extensively infiltrate salivary glands, may be responsible for the production of class-switched immunoglobulin in SS. In addition, those cells might be associated with the inflammation and tissue damage of the salivary glands.

Hypoxia-dependent anti-inflammatory pathways in protection of cancerous tissues.

The evolutionarily selected tissue-protecting mechanisms are likely to be triggered by an event of universal significance for all surrounding cells. Such an event could be damage to blood vessels, which would result in local tissue hypoxia. It is now recognized that tissue hypoxia can initiate the tissue-protecting mechanism mediated by at least two different biochemical pathways. The central message of this review is that tumor cells are protected from immune damage in hypoxic and immunosuppressive tumor microenvironments due to the inactivation of anti-tumor T cells by the combined action of these two hypoxia-driven mechanisms. Firstly, tumor hypoxia-produced extracellular adenosine inhibits anti-tumor T cells via their G(s)-protein-coupled and cAMP-elevating A2A and A2B adenosine receptors (A2AR/A2BR). Levels of extracellular adenosine are increased in tumor microenvironments due to the changes in activities of enzymes involved in adenosine metabolism. Secondly, TCR-activated and/or tumor hypoxia-exposed anti-tumor T cells may be inhibited in tumor microenvironments by Hypoxia-inducible Factor 1alpha (HIF-1alpha) Hence, HIF-1alpha activity in T cells may contribute to the tumor-protecting immunosuppressive effects of tumor hypoxia. Here, we summarize the data that support the view that protection of hypoxic cancerous tissues from anti-tumor T cells is mediated by the same mechanism that protects normal tissues from the excessive collateral damage by overactive immune cells during acute inflammation.

The association of Behçet's disease with myelodysplastic syndrome in Japan: a review of the literature.

OBJECTIVE: [corrected] To determine the clinical characteristics of patients with myelodysplastic syndrome (MDS)-associated Behçet's disease (BD) in Japan. METHODS: 54 Japanese cases of MDS-associated BD obtained from the literature and from our own clinical experience were reviewed. The clinical features of MDS-associated BD were compared with those of the 1991 nationwide BD survey in Japan. RESULTS: In MDS-associated BD, the average age at onset was 42.6 years, which was 6.9 years later than for all BD patients; females developed disease more frequently than males (male: female ratio = 0.80). In MDS-associated BD cases, the occurrence of eye lesions was significantly lower, the frequency of intestinal lesions was markedly higher, and the rate of HLA-B51 positivity was lower than that in all BD. BD and MDS developed nearly simultaneously in 49.0% of cases; BD preceded MDS in 31.4% of the cases. The distribution of the age at BD onset showed two peaks, one in the 3rd decade and the other in the 6th decade. Females were more likely to develop younger-onset disease, while men were more likely to develop older-onset MDS-associated BD. Furthermore, in the older-onset group, BD was diagnosed together with or after the diagnosis of MDS, while half of the younger-onset group developed BD earlier than MDS. CONCLUSION: MDS-associated BD patients form a distinct subset of patients. There may, in fact, be two major groups of MDS-associated BD patients based on age, gender, and temporal relationship of the two diseases.

Impact of reproductive experience on women's smoking behaviour in Japanese nurses.

OBJECTIVES: The objectives of this study were to describe current and past smoking behaviour of female Japanese nurses, to examine factors associated with developing and stopping a smoking habit, and to examine how their reproductive experiences affect their smoking behaviour. STUDY DESIGN: A cross-sectional study. This study was a baseline survey of a prospective occupational cohort study. METHODS: A self-administered survey of 1748 female Japanese nurses aged over 20 years was conducted in Gunma prefecture, Japan, in 1999. RESULTS: Overall, 27.2% developed a smoking habit (current smokers, 19.8%; ex-smokers, 7.4%) and 72.2% were never smokers. Logistic regression analysis showed that the type of nursing certificate was statistically associated with developing a smoking habit. It also showed that the type of nursing certificate, work place, marital status and current pregnancy were statistically associated with smoking cessation. Currently pregnant women were more likely to stop smoking than non-pregnant women (adjusted odds ratio, 3.18; 95% confidence intervals, 1.25-8.06). For women aged 20-29 years, the proportions of current smokers, ex-smokers and never smokers among pregnant women were 11.5, 23.1 and 65.4%, respectively; among non-pregnant women of this age, the values were 22.3, 4.3 and 73.4%, respectively. There was a statistically significant difference in such proportions between the two groups (chi2=19.27; P<0.0001). More than half of the ex-smokers who were currently pregnant had stopped smoking in the last 12 months. Smoking behaviour showed no statistically significant difference between women who had had at least one delivery and women who had not. CONCLUSIONS: The results suggest that pregnancy provides a good opportunity for smoking cessation, but a large proportion of women who successfully quit smoking during pregnancy relapse after delivery.

Activation of the Ras-cAMP signal transduction pathway inhibits the proteasome-independent degradation of misfolded protein aggregates in the endoplasmic reticulum lumen.

Many kinds of misfolded secretory proteins are known to be degraded in the endoplasmic reticulum (ER). Dislocation of misfolded proteins from the ER to the cytosol and subsequent degradation by the proteasome have been demonstrated. Using the yeast Saccharomyces cerevisiae, we have been studying the secretion of a heterologous protein, Rhizopus niveus aspartic proteinase-I (RNAP-I). Previously, we found that the pro sequence of RNAP-I is important for the folding and secretion, and that Deltapro, a mutated derivative of RNAP-I in which the entire region of the pro sequence is deleted, forms gross aggregates in the yeast ER. In this study, we show that the degradation of Deltapro occurs independently of the proteasome. Its degradation was not inhibited either by a potent proteasome inhibitor or in a proteasome mutant. We also show that neither the export from the ER nor the vacuolar proteinase is required for the degradation of Deltapro. These results raise the possibility that the Deltapro aggregates are degraded in the ER lumen. We have isolated a yeast mutant in which the degradation of Deltapro is delayed. We show that the mutated gene is IRA2, which encodes a GTPase-activating protein for Ras. Because Ira2 protein is a negative regulator of the Ras-cAMP pathway, this result suggests that hyperactivation of the Ras-cAMP pathway inhibits the degradation of Deltapro. Consistently, down-regulation of the Ras-cAMP pathway in the ira2 mutant suppressed the defect of the degradation of Deltapro. Thus, the Ras-cAMP signal transduction pathway seems to control the proteasome-independent degradation of the ER misfolded protein aggregates.

Double-Switch operation for congenitally corrected transposition.

Double-switch operation was performed in 76 patients with congenitally corrected transposition of the great arteries at the Heart Institute of Japan, Tokyo Women's Medical University. Detailed surgical techniques of Mustard and Senning procedures for inlet switch, as well as arterial switch operation, pulmonary reconstruction by direct right ventricular-pulmonary arterial anastomosis, and external conduit repair for outlet switch are described in detail.

[Autoimmune hepatitis associated with mixed connective tissue disease: report of a case and a review of the literature].

A case is reported of a 29 year old female who had autoimmune hepatitis associated with mixed connective tissue disease (MCTD). The patient developed MCTD at the age of 19, and was treated with prednisolone. Liver dysfunction developed 7 years later, which exacerbated shortly after the patient suffered intrauterine fetal death during the second trimester of pregnancy. Laboratory data showed negative anti-hepatitis C antibody and hepatitis B antigen, but positive anti-smooth muscle antibody. A liver biopsy showed chronic active hepatitis. Referring to the criteria we diagnosed her as having autoimmune hepatitis. Although hepatomegaly is sometimes observed in MCTD patients, only 5 cases of autoimmune hepatitis associated with MCTD have been reported in the past. In our case, it is of note that autoimmune hepatitis developed while symptoms of MCTD were in remission, and that autoimmune hepatitis exacerbated with the emergence of anti-smooth muscle antibody following the termination of pregnancy.

Collagen-induced arthritis in TNF receptor-1-deficient mice: TNF receptor-2 can modulate arthritis in the absence of TNF receptor-1.

TNF is a potent proinflammatory cytokine important for the development of arthritis in human and animals. We have investigated the roles of TNF receptor-1 (TNFR1) and TNF receptor-2 (TNFR2) in collagen-induced arthritis (CIA) by inducing CIA in mice genetically deficient in TNFR1. TNFR1-/- mice developed arthritis with similar incidence and severity as TNFR1+/- littermates, indicating that TNFR1 is redundant for the development of CIA. Anti-type II collagen (CII) antibody levels and T cell responses to CII did not differ between TNFR1-/- mice and controls. Neutralization of TNF with soluble TNF binding protein suppressed the development of arthritis in TNFR1+/- mice but not in TNFR1-/- mice, indicating that TNFR2 cannot substitute for TNFR1 for the proinflammatory function. To further investigate the functions of TNFR2, TNFR1-/- mice were injected with murine TNF-alpha at different stages during the course of CIA. Repeated TNF-alpha injection during the early induction phase enhanced the development of arthritis, but inhibited arthritis when administered during the late progression phase. These results show that the engagement of TNFR2 by TNF is involved in the development of CIA in the absence of TNFR1 and that opposing signals can be transduced by TNFR2.

Smoking and mental health: cross-sectional and cohort studies in an occupational setting in Japan.

BACKGROUND: The relationship between smoking and mental health remains unclear. METHODS: We carried out a cross-sectional study and a cohort study on the possible association of smoking and mental health in 782 workers. Using a questionnaire including the 30-item General Health Questionnaire (GHQ-30) and items related to the smoking state, the association between smoking and mental health was evaluated separately in males and females. The subjects were classified into smokers and nonsmokers, and changes in the GHQ score during a 2-year follow-up period were evaluated. To control potential confounding factors, multiple regression analyses were performed. RESULTS: The cross-sectional study showed no difference in the GHQ score between smokers and nonsmokers among males but a significantly higher GHQ score for smokers than nonsmokers among females. This difference among females was confirmed to be significant by multiple regression analysis. The 2-year cohort study showed a decrease in the GHQ score in each group and no reduction in the difference in the GHQ score between smokers and nonsmokers among females. CONCLUSIONS: No difference was observed in mental health between smokers and nonsmokers in males. However, in females, smokers showed poorer mental health than nonsmokers, and this difference remained unchanged even after 2 years.

Role of G-protein-coupled adenosine receptors in downregulation of inflammation and protection from tissue damage.

Inappropriate or prolonged inflammation is the main cause of many diseases; for this reason it is important to understand the physiological mechanisms that terminate inflammation in vivo. Agonists for several Gs-protein-coupled receptors, including cell-surface adenosine purinergic receptors, can increase levels of immunosuppressive cyclic AMP in immune cells; however, it was unknown whether any of these receptors regulates inflammation in vivo. Here we show that A2a adenosine receptors have a non-redundant role in the attenuation of inflammation and tissue damage in vivo. Sub-threshold doses of an inflammatory stimulus that caused minimal tissue damage in wild-type mice were sufficient to induce extensive tissue damage, more prolonged and higher levels of pro-inflammatory cytokines, and death of male animals deficient in the A2a adenosine receptor. Similar observations were made in studies of three different models of inflammation and liver damage as well as during bacterial endotoxin-induced septic shock. We suggest that A2a adenosine receptors are a critical part of the physiological negative feedback mechanism for limitation and termination of both tissue-specific and systemic inflammatory responses.

Wild type ApoA-II gene does not rescue senescence-accelerated mouse (SAMP1) from short life span and accelerated mortality.

Biochemical and genetic data suggest that the Apoa2c allele of the apolipoprotein A-II gene causes severe senile amyloidosis (AApoAII) in SAMP1, a mouse model for accelerated senescence. We analyzed the effects of replacement of Apoa2c in SAMP1 mice with non-amyloidogenic Apoa2b on amyloidosis, lipoprotein metabolism, and progression of senescence using a congenic strain, P1.R1-Apoa2b, which has the Apoa2b chromosome region of SAMR1 in the genome of SAMP1. Age-associated amyloid deposition was not observed, but plasma concentrations of apoA-II protein and HDL-cholesterol decreased with age in P1.R1-Apoa2b. P1.R1-Apoa2b showed lower scores of senescence than did SAMP1. However, the life span and mortality rate doubling time were similar in P1.R1-Apoa2b and SAMP1. These results suggest that replacement of Apoa2c with non-amyloidogenic Apoa2b does not rescue SAMP1 mice from a short life span and accelerated mortality.

The critical role of Th1-dominant immunity in tumor immunology.

To investigate the precise role of antigen-specific Th1 and Th2 cells in tumor immunity, we developed a novel adoptive tumor-immunotherapy model using OVA-specific Th1 and Th2 cells and an OVA gene-transfected tumor. This therapeutic model demonstrated that both antigen-specific Th1 and Th2 cells had strong antitumor activity in vivo with distinct mechanisms. However, immunological memory suitable for the generation of tumor-specific cytotoxic T lymphocytes was induced only when tumor-bearing mice received Th1 cell therapy, but not Th2 cell therapy. Thus it was strongly suggested that Th1-dominant immunity is critically important for the induction of antitumor cellular immunity in vivo. We also proposed that several immunomodulating protocols using interleukin (IL)-12, IL-12 gene, the natural killer T cell ligand alpha-galactosylceramide, or Th1 cytokine-conditioned dendritic cells might be useful strategies for the induction of Th1-dominant immunity essential for the development of tumor-specific immunotherapy.

The interface between innate and acquired immunity: glycolipid antigen presentation by CD1d-expressing dendritic cells to NKT cells induces the differentiation of antigen-specific cytotoxic T lymphocytes.

In vivo administration of NKT cell ligand, alpha-galactosylceramide (alpha-GalCer), caused the activation of NKT cells to induce a strong NK activity and cytokine production by CD1d-restricted mechanisms. Surprisingly, we also found that alpha-GalCer induced the activation of immunoregulatory cells involved in acquired immunity. Specifically, in vivo administration of alpha-GalCer resulted in the induction of the early activation marker CD69 on CD4(+) T cells, CD8(+) T cells and B cells in addition to macrophages and NKT cells. However, no significant induction of CD69 was observed on cells from CD1d- or V(alpha)14 NKT-deficient mice, indicating an essential role for the interaction between NKT cells and CD1d-expressing dendritic cells (DC) in the activation of acquired immunity in response to alpha-GalCer. Indeed, in vivo injection of alpha-GalCer resulted not only in the activation of NKT cells but also in the generation of CD69(+)CD8(+) T cells possessing both cytotoxic T lymphocyte (CTL) activity and IFN-gamma-producing ability. Tumor-specific CTL generation was also accelerated by alpha-GalCer. The critical role of CD40-CD40 ligand (CD40L)-mediated NKT-DC interaction during the development of CD69(+)CD8(+) CTL by alpha-GalCer was demonstrated by blocking experiments using anti-CD40L mAb. These findings provide direct evidence for a critical role of CD1d-restricted NKT cells and DC in bridging innate and acquired immunity.

Indispensable role for TNF-alpha and IFN-gamma at the effector phase of liver injury mediated by Th1 cells specific to hepatitis B virus surface antigen.

We report the development and characterization of a novel model of severe hepatitis induced against hepatitis B virus surface Ag (HBsAg). HBsAg was successfully targeted into the liver in soluble form. Using this unique property of HBsAg, we established a liver injury model induced by HBsAg-specific Th1 cells. Severe liver injury was induced in C57BL/6 mice by injection of HBsAg together with HBsAg-specific Th1 cells. Histochemical examination demonstrated extensive necroinflammatory hepatic lesions in these animals. Application of this liver injury model to mutant or gene knockout mice enabled us to define the effector mechanisms of Th1 cells in fulminant hepatitis. When Fas-deficient lpr mice were used as recipients, a similar degree of liver injury was induced as in wild-type mice. Moreover, HBsAg-specific Th1 cells obtained from perforin-/- mice could induce severe liver injury in both wild-type and lpr mice. These results indicated that neither Fas ligand nor perforin are essential for Th1-mediated liver injury in this model. Pretreatment with anti-TNF-alpha mAb prevented liver injury, whereas severe liver injury was induced in TNF-alpha-/- mice. Moreover, IFN-gamma receptor-deficient mice were resistant to Th1-mediated liver injury. Therefore, TNF-alpha and IFN-gamma, which were produced by HBsAg-specific Th1 cells during the effector phase, appeared to be indispensable in the pathogenesis of fulminant hepatitis.