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Foxp3+Regulatory T cells (Tregs) play a critical role in the maintenance of colon homeostasis. Here we utilized photoconvertible KikGR mice to track immune cells from the caecum and ascending (proximal) colon in the steady state and DSS-induced colitis. We found that Tregs from the proximal colon (colonic migratory Tregs) migrated exclusively to the distal part of mesenteric lymph nodes (dMLN) in an S1PR1-dependent process. In the steady state, colonic migratory CD25+Tregs expressed higher levels of CD103, ICOS, LAG3 and CTLA-4 in comparison with pre-existing LN Tregs. Intestinal inflammation led to accelerated Treg replacement in the colon, bidirectional Treg migration from the colon to dMLN and vice versa, as well as increases in Treg number, proliferation and expression of immunosuppressive molecules. This was especially apparent for CD25 very high Tregs induced in colitis. Furthermore, colonic migratory Tregs from the inflamed colon included more interleukin (IL)-10 producing cells, and demonstrated greater inhibition of T-cell proliferation in comparison with pre-existing LN Tregs. Thus, our results suggest that Tregs with superior immunosuppressive capacity are increased both in the colon and dMLN upon inflammation. These Tregs recirculate between the colon and dMLN, and are likely to contribute to the downregulation of intestinal inflammation.

Foxp3+Regulatory T cells (Tregs) play a critical role in the maintenance of colon homeostasis. Here we utilized photoconvertible KikGR mice to track immune cells from the caecum and ascending (proximal) colon in the steady state and DSS-induced colitis. We found that Tregs from the proximal colon (colonic migratory Tregs) migrated exclusively to the distal part of mesenteric lymph nodes (dMLN) in an S1PR1-dependent process. In the steady state, colonic migratory CD25+Tregs expressed higher levels of CD103, ICOS, LAG3 and CTLA-4 in comparison with pre-existing LN Tregs. Intestinal inflammation led to accelerated Treg replacement in the colon, bidirectional Treg migration from the colon to dMLN and vice versa, as well as increases in Treg number, proliferation and expression of immunosuppressive molecules. This was especially apparent for CD25 very high Tregs induced in colitis. Furthermore, colonic migratory Tregs from the inflamed colon included more interleukin (IL)-10 producing cells, and demonstrated greater inhibition of T-cell proliferation in comparison with pre-existing LN Tregs. Thus, our results suggest that Tregs with superior immunosuppressive capacity are increased both in the colon and dMLN upon inflammation. These Tregs recirculate between the colon and dMLN, and are likely to contribute to the downregulation of intestinal inflammation.

Large numbers of fillet-welded cruciform joints are extensively employed at the connection zones of steel structural members because of their superiority from consideration of ease of construction and economy. Where this welded cruciform joint becomes a load-carrying type, the fatigue fracture starting point will be either at the weld toe zone, the root zone or both, so the fatigue behaviour becomes complex. In particular, when root fracture takes place, the fatigue strength is low compared with other welded joints and also it is difficult to detect by means of non-destructive inspection at the initial stage of crack occurrence; consequently there are some cases where fatigue becomes a problem.

Abstract:  An optimal packing problem of non-convex polygons on a sheet is considered and applied to a textile nesting problem. We propose a procedure of grouping objects and adaptive meta-heuristics. The grouping procedure classifies objects into groups which are then allocated on the sheet using adaptive meta-heuristics. As a result, effectiveness of the meta-heuristics is improved. The performance of the proposed method is compared with other meta-heuristics using simulation experiments. The result shows that the present method is superior to cases where adaptive meta-heuristics without grouping are used.

Abstract: The present study was designed to determine the frequency of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection in patients with hepatocellular carcinoma (HCC) in Nagasaki Prefecture, Japan. We examined the clinical features of 1019 patients with HCC who visited our hospitals between January and December 1999. The ratio of men to women was 709 : 310, and the peak incidence of HCC was in the seventh decade of life in both men and women. In the majority of the patients, HCC showed association with HCV infection (74%) compared with HBV infection (17%). HBV-associated HCC was more common in young patients, while HCV-associated HCC was more common in patients with a history as a "daily drinker", or with a history of blood transfusion, liver cirrhosis, and persistently high serum transaminases before the diagnosis of HCC. HCC was initially suspected by ultrasonography or computed tomography in 776 of the 874 patients for whom there was a history of mode of detection of HCC (89%). Tumor size at the time of diagnosis of HCC in patients who had been regularly followed up for liver diseases at our hospitals was significantly smaller than that in patients who were not followed up regularly before the diagnosis (P < 0.01). Our results indicate that the proportions of patients with HBV or with HCV infection among HCC patients in Nagasaki Prefecture are similar to those found in a nationwide survey in Japan, and there are some differences between the clinical manifestations of HBV- and HCV-associated HCC. Our results emphasize the importance of close follow-up for the high-risk group (i.e. those with HBV- or HCV-associated chronic liver diseases) for the early detection of HCC.

The solubilization of two water-insoluble dyes, o-(2-amino-1-naphthylazo)toluene (OY) and 1-pyrenecalbaldehyde (PyA), by complexes of anionic polyelectrolyte and alkyltrimethylammonium bromide (C12TAB, C14TAB, C16TAB) was examined using sodium poly(vinyl sulfate) (PVS) with different charge densities at 298.2 K. The change in the Gibbs function was estimated for this solubilization equilibrium. These complexes showed a larger solubilizing capacity for OY than for PyA. Their capacity for OY was larger than that of the corresponding surfactant micelles. The charge density of PVS influenced the solubilizing capacity in C12TAB and C14TAB solutions but had little effect in C16TAB solutions. PVS with a 40% charge density had the lowest solubilizing capacity. Bound short-chain surfactants are expected to have a smaller lateral interaction with neighboring surfactants bound to PVS with a lower charge density, thus forming a less hydrophobic complex with a lower solubilization capacity. The observed weak solubilization by PVS with a low charge density was ascribed to this less hydrophobic complex.

Alzheimer's disease is characterized by extensive cerebral amyloid deposition. Amyloid deposits associated with damaged neuropil and blood vessels contain abundant fibrils formed by the amyloid beta-protein (Abeta). Fibrils, both in vitro and in vivo, are neurotoxic. For this reason, substantial effort has been expended to develop therapeutic approaches to control Abeta production and amyloidogenesis. Achievement of the latter goal is facilitated by a rigorous mechanistic understanding of the fibrillogenesis process. Recently, we discovered a novel intermediate in the pathway of Abeta fibril formation, the amyloid protofibril (Walsh, D. M., Lomakin, A., Benedek, G. B., Condron, M. M., and Teplow, D. B. (1997) J. Biol. Chem. 272, 22364-22372). We report here results of studies of the assembly, structure, and biological activity of these polymers. We find that protofibrils: 1) are in equilibrium with low molecular weight Abeta (monomeric or dimeric); 2) have a secondary structure characteristic of amyloid fibrils; 3) appear as beaded chains in rotary shadowed preparations examined electron microscopically; 4) give rise to mature amyloid-like fibrils; and 5) affect the normal metabolism of cultured neurons. The implications of these results for the development of therapies for Alzheimer's disease and for our understanding of fibril assembly are discussed.

Pretreatment of human peripheral blood monocytes with a very low concentration (0.1 ng/ml) of Porphyromonas gingivalis lipopolysaccharides (LPS) resulted in a significant decrease of interleukin-6 (IL-6) production, but not IL-8 production, by restimulation of a high concentration (1 microg/ml) of the same LPS. In contrast, the same pretreatment with Escherichia coli LPS resulted in the enhanced production of both IL-6 and IL-8 after restimulation. The selective induction by P. gingivalis LPS tolerance of IL-6 production developed in a time-dependent manner during the primary culture. P. gingivalis LPS-pretreated cells were also refractory to a high-dose E. coli LPS restimulation in terms of IL-6 production. The expression of IL-6 mRNA decreased 10 h after restimulation of P. gingivalis LPS-pretreated monocytes. Furthermore, an up-regulation of anti-inflammatory cytokine IL-10 upon a second high-dose LPS rechallenge occurred at the same time point in the pretreated cells. We studied the role of IL-10 in the process of IL-6 down-regulation. Neutralization by an anti-IL-10 polyclonal antibody prevented IL-6 down-regulation in P. gingivalis LPS-pretreated monocytes, whereas IL-8 production was not affected. Addition of exogenous IL-10 during the high-dose LPS stimulation of untreated cells substituted for the LPS pretreatment and resulted in the inhibition of IL-6 production in a dose-dependent manner. A higher dose of IL-10 was required to suppress IL-8 synthesis from monocytes. Our data suggest that IL-10 mediates IL-6 down-regulation in P. gingivalis LPS-tolerant monocytes in an autocrine manner.

We detected and quantified tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) from monocytes/macrophages (M phi) in the peripheral blood of subjects from three different population groups, i.e., tuberculin-negative healthy subjects, tuberculin-positive healthy subjects, and patients with active pulmonary tuberculosis. TNF-alpha or IL-6 activity in the culture supernatant of these cells was determined by the cytotoxicity of murine L-929 cells or by enzyme-linked immunosorbent assay, respectively. Detection and enumeration of cells secreting either TNF-alpha or IL-6 were performed by an adaptation of the enzyme-linked immunospot assay. Monocytes/M phi from tuberculin-positive healthy subjects or patients with tuberculosis showed higher TNF-alpha- and IL-6-producing activities than those from tuberculin-negative healthy subjects. The number of TNF-alpha- and IL-6-secreting cells in either lipopolysaccharide- or muramyl dipeptide-stimulated mononuclear cells from tuberculin-positive healthy subjects and patients was significantly higher than that in cells from the tuberculin-negative healthy subjects.

Potentiometric and spectroscopic studies of a chlorophyll a (Chl)−copolypeptide of l-ornithine and l-tyrosine (poly(l-Orn, l-Tyr)) system in aqueous solutions of sodium dodecyl sulfate (SDS) were carried out. The cooperative binding of SDS to poly(l-Orn, l-Tyr) studied by the potentiometric measurement of the binding isotherm showed that coil to α-helix transition of the poly(l-Orn, l-Tyr)−SDS complex takes place with an increase in SDS concentration. An increase in the helix content of poly(l-Orn, l-Tyr)−SDS complex can be well interpreted in terms of the hydrophobic interaction among bound SDS ions. On the basis of theoretical analysis of the cooperative binding isotherm, it was concluded that the formation of a micelle-like cluster consisting of at least seven SDS ions is required for the stabilization of a surfactant-induced helical structure. Singlet excitation energy transfer between l-Tyr-containing copolypeptide and Chl was investigated with steady-state fluorescence spectroscopy, and the efficiency of energy transfer from l-Tyr to Chl was evaluated as a function of SDS concentration or the degree of binding of SDS ion to poly(l-Orn, l-Tyr). We also determined energy-transfer parameters such as critical transfer distance and effective mean distance between l-Tyr and Chl, based on the Förster theory. It was shown that the effective mean distance varies from 49 to 34 Å with an increse in SDS concentration or the degree of binding, and the effective local concentration of Chl acceptor is about 350 times larger than the analytical concentration (1.0 × 10^-5 M); thus it can be concluded that Chl molecules are highly concentrated in poly(l-Orn, l-Tyr)−SDS complexes and Chl and l-Tyr are located close to each other. Resonance Raman spectra of the Chl−poly(l-Orn, l-Tyr)−SDS system indicated that the keto-carbonyl at the 9-position of Chl interacts with phenol side chain of l-Tyr in poly(l-Orn, l-Tyr) via hydrogen bond. Therefore, it is reasonable to assume the formation of Chl−poly(l-Orn, l-Tyr) complexes in the presence of SDS. The present results on quantum yields of Chl fluorescence and energy transfer indicate that Chl molecules are incorporated into poly(l-Orn, l-Tyr)−surfactant complexes accompanying conformational change from the random coil to α-helix, and then the conformation-dependent energy transfer effectively occurs from l-tyrosine residue to Chl in the Chl−copolypeptide−surfactant system.