青枯病菌に感染するバクテリオファージの解析とバイオコントロールへの利用

広島大学(Hiroshima University)博士(理学)doctora

Lactobacillus Acidophilus Strain L-92 Regulates the Production of Th1 Cytokine as well as Th2 Cytokines

ABSTRACTBackgroundThere is growing interest in probiotics such as lactic acid bacteria (LAB), not only for treatment of T helper type (Th) 1-mediated diseases but also for Th2-mediated diseases, including allergic diseases, since lactic acid bacteria may be able to modulate the Th1/Th2 balance, in addition to having an immunomodulative effect through induction of Th1 bias.MethodsThe effect of oral administration of heat-killed Lactobacillus acidophilus Strain L-92 (L-92) on ovalbumin (OVA)-specific immunoglobulin (Ig)E production was investigated in BALB/c mice. L-92 was orally administered to mice for 8 weeks from 2 weeks after initiation of OVA-immunization. Patterns of cytokine and Ig production in splenocytes and cells from Peyer’s patches (PPs) from these mice were examined after restimulation with OVA in vitro.ResultsL-92 significantly suppressed serum OVA-specific IgE levels for a long period. Cytokines such as interferon (IFN)-γ, interleukin (IL)-4 and IL-10 and Igs such as total IgE and OVA-specific IgE were produced at significantly lower levels by splenocytes of L-92-treated mice, compared with those of control mice. In contrast, transforming growth factor (TGF)-β and IgA levels produced by PPs from L-92-treated mice were significantly higher than in those from control mice.ConclusionsOral L-92 administration regulated both Th1 and Th2 cytokine responses, suppressed serum OVA-specific IgE, and induced TGF-β production in PPs. TGF-β is known to be associated with activation of regulatory T (Treg) cells. These data suggest that LAB may have immunomodulative effect by Treg cells via TGF-β activity

ニュウインチュウ ノ ガクドウ ヲ モツ ハハオヤ ヘ ノ ケア ニ カンスル ケントウ ハハオヤ ノ キタイ ト カンゴシ ノ ニンシキ ノ サイ

原

Simple surrogate index of the fibrosis stage in chronic hepatitis C patients using platelet count and serum albumin level.

This study was conducted to develop a simple surrogate index comprised of routinely available laboratory tests to reflect the histological fibrosis stage. Clinical characteristics and laboratory data from 368 and 249 consecutive patients with chronic hepatitis C, a training cohort and a validation cohort, respectively, were retrospectively evaluated. Platelet (Plt) count and albumin (Alb) level contributed to the discrimination of the respective fibrosis stages. We derived the fi brosis index (FI), FI = 8.0-0.01 x Plt (10 multiply 3/microliter) - Alb (g/dl), from a multiple regression model. FI significantly correlated with the histological fibrosis stage in both the initial and validation cohort at p=0.691 and p=0.661, respectively (Spearman's rank correlation coefficient, p&#60;0.0001). The sensitivity and positive predictive value of FI at a cutoff value &#60; 2.10 for predicting fibrosis stage F0-1 were 66.8% and 78.8% in the initial cohort and 68.5% and 63.6% in the validation cohort, respectively. Corresponding values of FI at a cutoff value &#62;- 3.30 for the prediction of F4 were 67.7% and 75.0% in the initial cohort and 70.8% and 81.0% in the validation cohort. The fibrosis index comprised of platelet count and albumin level reflected the histological fibrosis stage in patients with chronic hepatitis C.</p

Glycine cleavage system in neurogenic regions

The glycine cleavage system (GCS) is the essential enzyme complex for degrading glycine and supplying 5,10-methylenetetrahydrofolate for DNA synthesis. Inherited deficiency of this system causes non-ketotic hyperglycinemia, characterized by severe neurological symptoms and frequent association of brain malformations. Although high levels of glycine have been considered to cause the above-mentioned problems, the detailed pathogenesis of this disease is still unknown. Here we show that GCS is abundantly expressed in rat embryonic neural stem/progenitor cells in the neuroepithelium, and this expression is transmitted to the radial glia-astrocyte lineage, with prominence in postnatal neurogenic regions. These data indicate that GCS plays important roles in neurogenesis, and suggest that disturbance of neurogenesis induced by deficiency of GCS may be the main pathogenesis of non-ketotic hyperglycinemi

Suppressive effects of transforming growth factor-beta1 produced by hepatocellular carcinoma cell lines on interferon-gamma production by peripheral blood mononuclear cells.

Transforming growth factor-beta1 (TGF-beta1) exerts potent immunosuppressive effects. In this study, we investigated the potential role of TGF-beta1 produced by hepatocellular carcinoma (HCC) cell lines in immunosuppression mechanisms. Using the Mv1Lu cell-growth inhibition assay and an enzyme-linked immunosorbent assay (ELISA), we detected optimal levels of TGF-beta1 in the culture supernatants conditioned by the HCC cell lines PLC/PRF/5, Hep3B, and HepG2. To determine the biological activity of TGF-beta1 in the supernatants, we examined the effects of the culture supernatants on the production of interferon (IFN)-gamma induced during the culture of peripheral blood mononuclear cells (PBMCs) stimulated with interleukin (IL)-12. IFN-gamma production of IL-12-stimulated PBMCs in the 1:1 dilution of the acid-activated conditioned medium of PLC/PRF/5, Hep3B, and HepG2 reduced to 14.7 +/- 0.8, 17.3 +/- 9.0, and 35.9 +/- 14.6%, respectively, compared with the value in the culture with control medium (complete culture medium). These results suggest that HCC cells producing TGF-beta1 may reduce the generation or activation of cytotoxic T lymphocytes (CTL) and natural killer (NK) cells, and thus could enhance their ability to escape immune-mediated surveillance.</p

Role of Survival Post-Progression in Phase III Trials of Systemic Chemotherapy in Advanced Non-Small-Cell Lung Cancer: A Systematic Review

BACKGROUND: In advanced non-small-cell lung cancer (NSCLC), with the increasing number of active compounds available in salvage settings, survival after progression to first-line chemotherapy seems to have improved. A literature survey was conducted to examine whether survival post-progression (SPP) has improved over the years and to what degree SPP correlates with overall survival (OS). METHODS AND FINDINGS: Median progression-free survival (MPFS) time and median survival time (MST) were extracted in phase III trials of first-line chemotherapy for advanced NSCLC. SPP was pragmatically defined as the time interval of MST minus MPFS. The relationship between MPFS and MST was modeled in a linear function. We used the coefficient of determination (r(2)) to assess the correlation between them. Seventy trials with 145 chemotherapy arms were identified. Overall, median SPP was 4.7 months, and a steady improvement in SPP was observed over the 20 years (9.414-day increase per year; p<0.001) in parallel to the increase in MST (11.253-day increase per year; p<0.001); MPFS improved little (1.863-day increase per year). Overall, a stronger association was observed between MST and SPP (r(2) = 0.8917) than MST and MPFS time (r(2) = 0.2563), suggesting SPP and MPFS could account for 89% and 25% of the variation in MST, respectively. The association between MST and SPP became closer over the years (r(2) = 0.4428, 0.7242, and 0.9081 in 1988-1994, 1995-2001, and 2002-2007, respectively). CONCLUSIONS: SPP has become more closely associated with OS, potentially because of intensive post-study treatments. Even in advanced NSCLC, a PFS advantage is unlikely to be associated with an OS advantage any longer due to this increasing impact of SPP on OS, and that the prolongation of SPP might limit the original role of OS for assessing true efficacy derived from early-line chemotherapy in future clinical trials