Biomedical subjects
Publications and source records attributed to H Okamura.
Six new xenicane diterpenes have been isolated from the acetone extract of the soft coral Xenia florida. Two of them are diterpenes containing a bicyclic [4.3.1] ring system. Three of them seem to be precursors for diterpenes possessing the bicyclic [4.3.1] ring system. One is a common monocarbocyclic diterpene with a cyclononane skeleton.
PURPOSE: To investigate the effect of understanding their own disease by patients with metastatic breast cancer on their survival potential after being informed by their physician. PATIENTS AND METHODS: Two hundred and fourteen women with metastatic breast cancer who participated in a multi-institutional, randomized phase III trial (Japan Clinical Oncology Group (JCOG) Study 8808) were asked whether they understood their own disease after being given information about the clinical trial. They were classified into two groups on the basis of whether they understood or not. We estimated their survival after the time of registration and derived relative hazard ratios from Cox's proportional hazards model. RESULTS: There were 190 patients in the 'better understanding' group and 24 in the 'poor understanding' group. Median survival times after registration were 28.3 and 16.1 months, respectively. The 'better understanding' group showed a significant difference from the 'poor understanding' group (p = 0.016). In multivariate regression analysis, patients who did not understand still showed poorer survival than those who understood (hazard ratio = 2.09; 95% confidence interval (CI) 1.16-3.78; p = 0.014). CONCLUSION: These results support the supposition that patients' understanding of information about their disease may influence their survival. Thus, it is important to evaluate patients' recognition about information even after obtaining their consent. However, further investigation is needed to clarify the exact nature of this relationship.
OBJECTIVES: To investigate the prevalence of and risk factors for psychological distress following first recurrences of breast cancer. PATIENTS AND METHODS: The sample was drawn consecutively from the inpatient and outpatient populations of the National Cancer Center Hospital in Japan during an 18-month period from July 1996 to December 1997. Of the 56 eligible patients, 55 women aged 30-73 year with recurrent breast cancer participated in the study. The prevalence of psychological distress, including major depressive disorder and adjustment disorders was evaluated according to the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Third edition-revised (DSM-III-R). Risk factors for psychological distress were analyzed with a logistic regression model. RESULTS: Of the 55 subjects, 42% met the DSM-III-R criteria for major depressive disorder or adjustment disorders. Major depressive disorder was seen in 4 (7%), and adjustment disorders in 19 (35%). Logistic regression analysis showed that a disease-free interval of less than 24 months significantly predicted a diagnosis of major depressive disorder or adjustment disorders (odds ratio 5.28, 95% confidence interval; 1.28-21.8, p = 0.02). CONCLUSIONS: These results suggest that it is important for all oncology staff to pay careful attention to the psychological health of patients who have been informed of their cancer recurrence, and that some psychosocial intervention is necessary for preventing distress in patients facing early recurrence.
Innate immune response to microbes sometimes determines the nature of the following specific immune response. Kupffer cells, a potent constituent of innate immunity, play a key role in developing the type 1 immune response by interleukin (IL)-12 production. Furthermore, Kupffer cells have the potential to induce liver injury by production of IL-18. Propionibacterium acnes-primed lipopolysaccharide (LPS)-challenged liver injury is the prototype of IL-18-induced tissue injury, in which IL-18 acts on natural killer cells to increase Fas ligand (FasL) that causes liver injury by induction of Fas-dependent hepatocyte apoptosis. LPS induces IL-18 secretion from Kupffer cells in a caspase-1-dependent manner. Indeed, caspase-1-deficient mice are resistant to P. acnes and LPS-induced liver injury. However, administration of soluble FasL induces acute liver injury in P. acnes-primed caspase-1-deficient mice but does not do so in IL-18-deficient mice, indicating that IL-18 release in a caspase-1-independent fashion is essential for this liver injury. Therefore, a positive feedback loop between FasL and IL-18 plays an important role in the pathogenesis of endotoxin-induced liver injury.
Overproduction of immunoglobulin E (IgE) and T helper cell type 2 (TH2) cytokines, including interleukin 4 (IL-4), IL-5 and IL-13, can result in allergic disorders. Although it is known that IL-4 is critical to the polarization of naïve CD4+ T cells to a TH2 phenotype, both in vitro and in many in vivo systems, other factors that regulate in vivo IL-4 production and TH2 commitment are poorly understood. IL-18, an IL-1-like cytokine that requires cleavage with caspase-1 to become active, was found to increase IgE production in a CD4+ T cells-, IL-4- and STAT6-dependent fashion. IL-18 and T cell receptor-mediated stimulation could induce naïve CD4+ T cells to develop into IL-4-producing cells in vitro. Thus, caspase-1 and IL-18 may be critical in regulation of IgE production in vivo, providing a potential therapeutic target for allergic disorders.
Precise temporal regulation of transcription is pivotal to the role of the mammalian pineal gland as a transducer of circadian and seasonal information. The circadian clock genes Per1 and Per2 encode factors implicated in temporally gated transcriptional programmes in brain and pituitary. Here we show that the nocturnal circadian expression of Per1 and Per2 in the rat pineal gland parallels that of serotonin N-acetyltransferase (NAT) mRNA, which encodes the rate-limiting enzyme of melatonin biosynthesis. This rhythm is dependent upon an intact sympathetic innervation. Increases in rPer1 (r indicates rat) and rPer2, as well as rNAT, expression during subjective night were blocked completely by superior cervical ganglionectomy (SCGX). In SCGX rats, the beta-adrenergic receptor agonist isoproterenol rapidly induced the rPer1 mRNA with dynamics very similar to its effect on rNAT mRNA. In contrast, isoproterenol was without effect on expression of rPer2 mRNA. These findings demonstrate that circadian pineal expression of both rPer1 and rPer2 is controlled by sympathetic afferent innervation, but whereas beta-adrenergic signalling regulates rPer1 and rNAT, an alternative route mediates sympathetic regulation over rPer2 expression.
Acute graft-versus-host disease (aGVHD) after allogeneic bone marrow transplantation (BMT) is mediated by grafted T lymphocytes after their polarization into type 1 T cells. Interleukin (IL)-18, a novel immunoregulatory cytokine, strongly stimulates type 1 T cells, therefore we postulated that IL-18 may be involved in the pathogenesis of aGVHD. Using an enzyme-linked immunosorbent assay (ELISA), we serially measured serum levels of IL-18 in 37 patients with haematological malignancy before and after allogeneic BMT. Patients with aGVHD had high levels of IL-18 that strongly correlated with the severity of aGVHD. We also found that they showed reduced serum levels of IL-18 after appropriate treatment or at a state of resolution. IL-18 levels were not affected by the pretransplant regimen, engraftment or bacterial infection. Compared with circulating interferon (IFN)-gamma or IL-12 levels, serum levels of IL-18 showed a more sensitive and specific correlation with the disease status of aGVHD. These findings suggest that IL-18 may play important roles in the pathogenesis of aGVHD and that measurement of serum IL-18 levels can be useful indicator of aGVHD.
The human chorionic gonadotropin (hCG) beta-core fragment (beta-CF) is a major molecular form of hCG beta subunit (hCGbeta) immunoreactivity in the urine of pregnant women and patients with trophoblastic disease. The majority of evidence supports the fact that the beta-CF is a degradative product of intact hCG and free hCGbeta in the kidneys. We found a beta-CF-like substance in the fluid of molar vesicles from a patient with complete hydatidiform mole. The molar fluid beta-CF (mbeta-CF) was indistinguishable from the beta-CF in the patient's urine (ubeta-CF) by immunoreactivity and by elution profile on gel chromatography. The binding study to lectins, however, showed that mbeta-CF contains a carbohydrate moiety that differs from that of ubeta-CF. Immunohistochemistry with anti-beta-CF antibody demonstrated a strong immunoreactivity in a large number of macrophages in the molar villous stroma. In vitro incubation of intact hCG with peritoneal macrophages showed a slow increase of intact hCG in the cell cytosol with the appearance of beta-CF-like substance in the cell supernatant. In conclusion, the source of beta-CF in molar fluid is likely to be macrophages existing in the villous stroma. Thus macrophages may ingest intact hCG and act as a local regulator of gonadotropic hormones.
We compared the structural and functional properties of three recombinant human interleukin-18 (rIL-18) preparations, commercially available (Pep rIL-18) and prepared in our laboratory (active and inactive, according to their ability to potentiate IL-12-mediated interferon-gamma [IFN-gamma] induction in lymphocytes). All three preparations showed multimer formation on SDS-PAGE/immunoblotting using monoclonal antibodies (mAb) against the inactive form of rIL-18. In contrast, only the 18-kDa bands were recognized in each sample by mAb against the active form of rIL-18. The amounts of multimers and the 18-kDa moiety of Pep rIL-18 resembled those of the inactive rather than the active form. Likewise, the reaction profile of Pep rIL-18 toward mAb was very similar to that of inactive but not active rIL-18 on sandwich ELISA. Pep rIL-18 potentiated IFN-gamma-inducing activity together with IL-12, but its potency was 100-fold less than that of the active rIL-18, and excess doses were required for its activity. The inactive rIL-18 showed virtually no IFN-gamma-inducing ability, but when reduced and reconstituted, it inhibited the IFN-gamma-inducing activity of active rIL-18. These results suggest that there are two categories of recombinant IL-18 that are structurally, functionally, and antigenically different, and the mAb 125-2H and 21 can discriminate these two IL-18 populations by recognizing the epitopes specifically expressed on active and inactive IL-18, respectively.
IL-18 is a proinflammatory cytokine that plays an important role in NK cell activation and T(h)1 response. IL-18 has a structural homology to IL-1, particularly IL-1beta. IL-18R, composed of IL-1R-related protein (IL-18Ralpha) and IL-1R accessory protein-like (IL-18Rbeta), belongs to the IL-1R family. Furthermore, IL-18R at least partly shares the signal transducing system with IL-1R. Thus, the IL-18-IL-18R system has a striking similarity to the IL-1-IL-1R system. For this reason, we regarded it important to investigate whether, like IL-18, IL-1beta synergizes with IL-12 in inducing IFN-gamma production from human T cells and plays an important role in the T(h)1 response. Here we show that IL-12 and IL-1beta synergistically induce T cells to proliferate and produce IFN-gamma without their TCR engagement. IL-12 stimulation induced an increase in the proportion of T cells positive for IL-18R. Then, IL-12-stimulated T cells responded to IL-18 or IL-1beta by their proliferation and IFN-gamma production, although levels of IL-1beta-induced responses were lower. CD4(+)CD45RA(+) T cells, although they constitutively expressed IL-18Rbeta mRNA, did not express IL-18Ralpha mRNA. Phytohemagglutinin (PHA) stimulation alone induced IL-18Ralpha mRNA without affecting the expression of IL-18Rbeta mRNA. T(h)1-inducing conditions (PHA, IL-12 and anti-IL-4) further increased this expression. We also show that T(h)1 cells but not T(h)2 cells have increased expression of IL-18R and IL-1R, and produce IFN-gamma in response to IL-18 and/or IL-1beta.
BACKGROUND: Major depression is a well-documented risk factor for suicide in cancer patients as well as in the general population. However, there are no data explaining why some cancer patients suffering from major depression have suicidal ideation whereas others with the same disorder do not. METHODS: We investigated the background differences between cancer patients suffering from major depression with and without suicidal ideation by analyzing consultation data on patients referred to the Psychiatry Division, National Cancer Center Hospital, Japan. RESULTS: Univariate analysis showed that poor performance status, advanced stage and severe depression were the risk factors for suicidal ideation in these depressive cancer patients. Multivariate logistic regression analysis indicated that older age and severe depression are the final significant risk factors. CONCLUSION: These preliminary findings suggest that severe major depression may be an important indicator of suicidal ideation among cancer patients, that patients' age should be given greater attention and that closer monitoring and more intensive intervention against major depression may be needed.
In this differential-display polymerase chain reaction-based study, four different primer sets generated cDNA fragments of ovarian carbonyl reductase genes that were uniquely expressed during the ovulatory process in eCG-primed immature rats. The temporal pattern of expression of this aldo-keto reductase gene was delineated by extracting ovarian RNA at 0, 2, 4, 8, 12, and 24 h after induction of ovulation via injection of the primed animals with hCG. The results showed that at least four homologous forms of this gene were transcribed during ovulation. Northern blot analyses indicated a 14-fold increase in ovarian mRNA for carbonyl reductase, with expression reaching a peak at 8 h after hCG treatment and then declining to negligible levels during the next 16 h. In situ hybridization revealed that most of the transcription was in the thecal connective tissue of the ovary and was absent from the granulosa layer of ovarian follicles. Treatment of the animals with ovulation-blocking doses of epostane (an inhibitor of progesterone synthesis) or indomethacin (an inhibitor of prostanoid synthesis) did not reduce the expression of ovarian carbonyl reductase. Nevertheless, the temporal pattern of expression of carbonyl reductase after the induction of ovulation suggests that this enzyme activity is at least indirectly associated with the ovulatory process.
In human chorionic villi, numerous macrophages, so-called Hofbauer cells, are located adjacent to trophoblasts. To determine the role of the macrophages in the proliferation and differentiation of trophoblasts, cytotrophoblast cells were cultured in serum-free culture-conditioned media of villous macrophages (VMCM), peritoneal macrophages (PMCM), and villous fibroblasts (VFCM). In VMCM, proliferation of cytotrophoblast cells was detected at 24 h by immunocytochemistry with Ki-67-antibody. A large number (P < 0.001) of multinucleated syncytia was formed in VMCM. In VMCM, cytotrophoblast cell fusion was completed by 96 h, which coincided with the peak of hCG secretion and initiation of human placental lactogen (hPL) release. Levels of hCG (P < 0.001) and hPL (P < 0. 001) secretion from syncytial cells were significantly higher in VMCM than in PMCM or in VFCM. Concentrations of macrophage colony-stimulating factor (M-CSF) and vascular endothelial growth factor (VEGF) analyzed by ELISA were greater in VMCM than in PMCM or in VFCM, whereas monocyte chemoattractant protein-1 (MCP-1) concentration was high in PMCM. The expression patterns of M-CSF, VEGF, and MCP-1 in villous macrophages and peritoneal macrophages by reverse transcriptase-polymerase chain reaction were similar to their secretion patterns. Thus, villous macrophages have a greater ability to stimulate hCG and hPL secretion than do peritoneal macrophages. This study suggests that macrophages within the villous stroma may stimulate the growth and differentiation of trophoblasts through their secreted substances.
The regulation of expression of cyclooxygenase 2 (COX-2) was investigated by treatment with PGE(2) in human endometrial adenocarcinoma cell line HEC-1B. One microM PGE(2) could stimulate the expression of COX-2 approximately twofold in this cell line. The same concentration of PGE(2) also stimulated activation of mitogen-activated protein kinase (MAP kinase) and protein kinase B (PKB). PGE(2)-induced MAP kinase activation was sensitive to a MAP kinase kinase (MEK) inhibitor, PD098059, and a protein kinase A inhibitor, H-89. PD098059 and H-89 also partially inhibited the expression of COX-2 stimulated by PGE(2). PGE(2) could stimulate the activation of PKB, which was sensitive to phosphatidylinositol-3-OH kinase (PI3K) inhibitor, wortmannin. Whereas wortmannin alone partially inhibited the expression of COX-2, a combination of wortmannin and PD098059 totally inhibited PGE(2)-mediated COX-2 expression. These results suggest that MAP kinase and PI3K pathways are stimulated with PGE(2), and that both of these pathways are involved in the expression of COX-2. In addition, they also suggest that protein kinase A remains upstream of PGE(2)-induced activation of MAP kinase in HEC-1B cells.
The ovulatory process in mammals begins when an endogenous surge in LH circulates to the ovary and couples with receptors in the plasma membranes of granulosa cells in mature ovarian follicles. This study provides evidence that the ovulatory stimulus includes induction of the gene for regulator of G-protein signaling protein-2 (RGS2). Immature Wistar rats were primed with 10 IU eCG s.c., and 48 h later the 12-h ovulatory process was initiated by 10 IU hCG (a homolog of LH) s.c. Ovarian RNA was extracted at 0, 2, 4, 8, 12, and 24 h after injecting the animals with hCG. The RNA extracts were used for reverse transcription-polymerase chain reaction differential display to detect gene expression in the stimulated ovarian tissue. Two of the amplified cDNAs that were upregulated within 2 h after the ovaries had been stimulated by hCG were homologous to segments of the mouse gene for RGS2. In situ hybridization indicated that the RGS2 mRNA was expressed in the granulosa layer of mature follicles. In conclusion, the gene for RGS2, which is known to regulate membrane signaling pathways, is transcribed in ovarian follicles in response to an ovulatory dose of gonadotropin.
Interleukin-18 (IL-18) is a proinflammatory cytokine that plays an important role in natural killer cell activation and the T helper 1 (Th1) cell response, particularly in collaboration with IL-12. Since Th1 cells play a pivotal role in the host defense against infection with intracellular microbes, such as Leishmania major, we investigated whether IL-18 is critically involved in protection against L. major infection by activation of Th1 cells. We administered IL-12 and/or IL-18 daily to L. major-susceptible BALB/c mice. Neither IL-12 (10 ng/mouse) nor IL-18 (1,000 ng/mouse) induced wound healing, while daily injection of IL-12 and IL-18 during the first week after infection strongly protected the mice from footpad swelling by induction and activation of Th1 cells. Furthermore, these mice acquired protective immunity. We also investigated a protective role of endogenous IL-18 by using anti-IL-18 antibody-treated C3H/HeN mice (an L. major-resistant strain) or IL-18 deficient (IL-18(-/-)) mice with a resistant background (C57BL/6). We found that in the absence of endogenous IL-18, these mice showed prolonged footpad swelling as well as diminished nitric oxide production. However, daily injection of IL-18 into IL-18(-/-) mice corrected their deficiencies, suggesting that these mice have Th1 cells that produce gamma interferon (IFN-gamma) in response to IL-18. Indeed, these mice had normal levels of Th1 cells. Thus, IL-18 is not responsible for inducing Th1 cells but participates in host resistance by its action in stimulating Th1 cells to produce IFN-gamma. Our results also indicate the high potentiality of IL-18 as a useful reagent for treatment as well as prevention against reinfection.
An earlier report (M. Sakaguchi et al., Vaccine 16:472-479, 1998) showed that recombinant Marek's disease virus type 1 (rMDV1) expressing the fusion (F) protein of Newcastle disease virus (NDV-F) under the control of the simian virus 40 late promoter [rMDV1-US10L(F)] protected specific pathogen-free chickens from NDV challenge, but not commercial chickens with maternal antibodies against NDV and MDV1. In the present study, we constructed an improved polyvalent vaccine based on MDV1 against MDV and NDV in commercial chickens with maternal antibodies. The study can be summarized as follows. (i) We constructed rMDV1 expressing NDV-F under the control of the MDV1 glycoprotein B (gB) promoter [rMDV1-US10P(F)]. (ii) Much less NDV-F protein was expressed in cells infected with rMDV1-US10P(F) than in those infected with rMDV1-US10L(F). (iii) The antibody response against NDV-F and MDV1 antigens of commercial chickens vaccinated with rMDV1-US10P(F) was much stronger and faster than with rMDV1-US10L(F), and a high level of antibody against NDV-F persisted for over 80 weeks postvaccination. (iv) rMDV1-US10P(F) was readily reisolated from the vaccinated chickens, and the recovered viruses were found to express NDV-F. (v) Vaccination of commercial chickens having maternal antibodies to rMDV1-US10P(F) completely protected them from NDV challenge. (vi) rMDV1-US10P(F) offered the same degree of protection against very virulent MDV1 as the parental MDV1 and commercial vaccines. These results indicate that rMDV1-US10P(F) is an effective and stable polyvalent vaccine against both Marek's and Newcastle diseases even in the presence of maternal antibodies.
Transcript levels of DBP, a member of the PAR leucine zipper transcription factor family, exhibit a robust rhythm in suprachiasmatic nuclei, the mammalian circadian center. Here we report that DBP is able to activate the promoter of a putative clock oscillating gene, mPer1, by directly binding to the mPer1 promoter. The mPer1 promoter is cooperatively activated by DBP and CLOCK-BMAL1. On the other hand, dbp transcription is activated by CLOCK-BMAL1 through E-boxes and inhibited by the mPER and mCRY proteins, as is the case for mPer1. Thus, a clock-controlled dbp gene may play an important role in central clock oscillation.