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Notes: Wavelength conversion has been demonstrated using a distributed feedback side-injection light-controlled bistable laser diode with an input wavelength range of 1496–1597 nm. Insensitivity to input light wavelength and a large separation ratio of output from input (more than 30 dB) are advantageous for a wavelength converter.

Notes: We demonstrate optical response from a side-injection light-controlled bistable laser diode buried with semi-insulating InP using hydride vapor phase epitaxy. The buried surface around both the 〈110〉 and 〈−110〉 oriented mesas is flat. The bistable operation is obtained by applying control voltage to the saturable absorption region. After optimization of the device parameters, we obtained error-free operation at a bit rate as high as 2.5 Gbit/s. © 1997 American Institute of Physics.

Notes: Vertical-cavity surface-emitting laser (VCSEL) structures have been grown on GaAs (311)B substrates by metalorganic chemical vapor deposition. C-doped GaAs and AlAs layers with smooth surface morphology and a hole concentration of 1018 cm−3 were obtained by optimizing the growth conditions; these conditions contributed to high-quality p-type distributed Bragg reflectors (DBRs). The devices on the (311)B substrates exhibited a threshold current of 9.6 mA, voltage of 2.1 V, and maximum power of 4.1 mW at a 20 μm φ size; these characteristics are similar to those obtained on (100) substrates. The polarization was aligned to [2¯33¯]. © 1997 American Institute of Physics.

Notes: Cell therapy with antigen-specific T cells holds promise for various diseases including cancer and viral infections. The powerful enrichment procedure based on major histocompatibility complex (MHC)-tetramers, however, is of limited applicability so far. Therefore, the recently developed cell surface affinity matrix technology that allows direct identification and enrichment of life antigen-specific T cells based on cytokine secretion was evaluated in this respect. To this end, CD8+ T cells directed against the HLA-A*0201-restricted melanoma-associated peptide Melan-A (aa26–35) were generated by combining stimulation of peptide-pulsed autologous dendritic cells (DC) with antigen-independent expansion with anti-CD3/anti-CD28 monoclonal antibodies (MoAb). Antigen-specific cytotoxic T lympocyte (CTL) were detected based on stimulation-induced interferon (IFN)-γ and interleukin (IL)-4 secretion and enriched 〉 100-fold using the cell surface affinity matrix technology. The resulting IFN-γ- and IL-4-secreting CTL lines contained 〉 80% and 〉 70% cytokine positive T cells, respectively. They exhibited a cytotoxic activity against Melan-A expressing target cells that was significantly higher as compared to nonpurified CTL. Direct staining of enriched CTL with HLA-A2-Melan-A-tetramers revealed a high correlation between the results obtained from the cell surface affinity matrix technology and those obtained from tetrameric complexes. Altogether, our study demonstrates that cytokine-driven enrichment based on the cell surface affinity matrix technology enables selective isolation of functionally active antigen-specific CTL that may be used for an adoptive T cell transfer in immunotherapy.

Notes: Background Recognition of foreign substances by innate immunity through pattern recognition receptors (PRRs) regulates acquired immunity such as allergic reaction. Because PRRs recognize heterogeneous ligands, daily food intake can potentially regulate immune allergic reaction.Objective Elucidation of the effect of λ-carrageenan on allergic reactions was aimed.Method IFN-γ and IL-4 was measured in in vitro T cell-stimulated culture. Cytokine production from macrophages in response to λ-carrageenan was measured as indicator for innate immunity activation. Mice were immunized with OVA in alum to induce specific IgE, and then histamine release was induced by systemic injection of OVA.Results Activation of innate immunity by λ-carrageenan is dependent on Toll-like receptor-4 (TLR4) and MyD88, in which induction of pro-inflammatory cytokines such as TNF-α and IL-6 was largely impaired in macrophages from TLR4- and MyD88-deficient mice. Footpad oedema, a model for in vivo inflammatory reactions, was significantly reduced in these mice. Similar to recent evidence showing a preference for the stimulation of Th1 via TLR/MyD88 signalling, λ-carrageenan showed enhanced IFN-γ and decreased IL-4 in stimulated T cell cultures. Interestingly, increased IFN-γ production was still seen in TLR4- and MyD88-deficient splenocytes. Oral administration of λ-carrageenan to immunized mice successfully decreased OVA-specific IgE, and λ-carrageenan was also effective in previously immunized mice. Further, serum histamine release upon systemic challenge of OVA was significantly inhibited. Neither OVA-specific IgG1/IgG2a nor cytokine secretion from in vitro cultures were altered, suggesting the involvement of multiple PRRs as demonstrated by TLR4/MyD88-independent IFN-γ up-regulation. The simultaneous feeding of OVA with lipopolysaccharide abrogated oral tolerance, but λ-carrageenan was not only devoid of such an effect but was also found to promote oral tolerance in the absence of TLR4.Conclusion λ-Carrageenan was suggested to be a useful dietary supplement to ameliorate allergic reactions while maintaining oral tolerance-dependent intestinal homeostasis.

Notes: Plasma fibronectin (FN) of flounder Paralichthys olivacem was purified and characterized. Flounder FN was purified by a combination of affinity chromatography using Sepharose coupled with flounder gelatin and gel filtration on Superose 6. Flounder FN was found to be a disulphide-linked heterodimer of 220 and 230 kDa polypeptides. It had cell-spreading activity for baby hamster kidney (BHK) cells, which was inhibited by the synthetic peptide, Gly-Arg-Gly-Asp-Ser-Pro. In flounder explants, anti-flounder FN antiserum distinguished fibroblast-like cells from epithelial cells; indirect immunofluorescence showed that the fibroblast-like cells exhibited a fibrous staining to the antiserum, but that epithelial cells did not. These results suggest that flounder FN is a homologue of mammalian FN.The localization of FN during re-epithelialization at the site of a severed fin was investigated. When the top of the fin was cut, epidermal cells covered the surface of the wound within 1 h. FN is detected at the wound site during epidermal cell migration, suggesting that it serves as a cell-adhesion factor for prompt re-epithelialization at wound sites.

Notes: Hatchery-reared honmasu salmon Oncorhynchus rhodurus × masou parr released into the Yanagisawa River, Tochigi Prefecture on 24 June 1996 increased significantly in length and weight by November, while siblings retained in hatchery tanks did not. Plasma growth hormone (GH) levels of the released parr increased from 1 day after the release until 23 August, while the GH levels of the wild parr in the river did not increase. The released parr started to consume various natural prey organisms within a day after release. However, stomach fullness of the released parr was considerably lower than that of the wild parr during the first week following release. Trypsin activity in the released parr increased after 23 August, 2 months post-release. The results demonstrate that the released parr adapt to the natural river environment within weeks. Endocrine control by GH and exocrine pancreas activity appear to play important roles in the post-release adaptation processes.

Notes: Most fish have a diffuse exocrine pancreas located around the internal organs, but its exact structure is not well understood. In this study, we developed a method for analysing zymogen granules using anti-fish trypsinogen, and the structure of the flounder pancreas was examined by localizing pancreatic exocrine cells. Anionic trypsinogen was purified from eel pancreas by chromatography using DE-52-cellulose and Superose 12 columns. Rabbit antiserum (anti-eel trypsinogen antibody: anti-eTrg) was raised against purified trypsinogen. Immunoblotting analysis demonstrated that anti-eTrg recognized two isoforms of eel trypsinogens and trypsins. This antibody also reacted with flounder trypsin. Zymogen granules containing trypsinogen were visualized within pancreatic glandular cells of the flounder Paralichthys olivaceus by immunohistochemistry using anti-eTrg. The flounder exocrine pancreas was reconstructed from observations of serial sections of digestive tract. The exocrine pancreas cells were localized along the hepatic portal vein and the veins running to the portal vein from the intestine, stomach, pyloric appendage and spleen, forming a highly branched tissue. Interlobular ducts from pancreatic acini formed a pancreatic duct covered with smooth muscle at the point where it met (but did not join) the bile duct. The pancreatic duct opened into the intestinal lumen at the basal portion of the third pyloric appendage in parallel with the bile duct.