Distribution of a novel angiotensin I-converting enzyme inhibitory substance (2″-hydroxynicotianamine) in the flour,plant parts,and processed products of buckwheat

2″-Hydroxynicotianamine (HNA) is a recently discovered angiotensin I-converting enzyme inhibitory compound present in buckwheat which displays hypotensive activity. Here, HNA levels in buckwheat flour, plants, and products were quantified to examine the potential functionality of this food. The HNA content of buckwheat flour ranged from 16–28 mg per 100 g dry weight. When the content was evaluated by the milling stage, common buckwheat contained 24.3, 24.1, and 34.1 mg in the inner, middle, and outer layers, respectively, whereas tartary buckwheat contained 16.8, 30.5, and 51.8 mg of HNA, respectively. Comparison of the distribution of HNA within buckwheat plants revealed that HNA was predominantly localised in seeds (buckwheat flour). The residual HNA levels after cooking ranged from 21% to 41% in dried buckwheat noodles. This study clarified that buckwheat flour contains high levels of HNA and is a readily available source of HNA if incorporated into one’s diet, which may help reduce hypertension.     

Lactococcus strains treated with heat and hen-egg-white lysozyme induce abundant interleukin-12 production by J774.1 macrophages and murine spleen cells

The IL-12-inducing ability of lactic acid bacteria could be a critical index of immunomodulatory activity, especially in promoting T-helper-1 responses and in suppressing T-helper-2-mediated allergic responses. We aimed to develop a simple method for enhancing the IL-12-inducing ability of bacteria. We examined the in vitro effects of strains of lysozyme-modified Lactococcus (ML-LYS), prepared by heat treatment of the Lactococcus strain in the presence of lysozyme, on the ability of mouse macrophage-like J774.1 cells and spleen cells to produce IL-12. An IL-12-inducing ability greater than that of heat-killed bacteria was shown by 41 of 46 ML-LYS strains in J774.1 cells and by all 46 ML-LYS strains in mouse spleen cells. In contrast, bacteria modified by α-lactalbumin, β-lactoglobulin, or ovalbumin did not enhance IL-12 production in J774.1 cells. Microscopically, ML-LYS showed stronger resistance to lysozyme and macrophage digestion than did heat-killed bacteria or the other modified bacteria. Addition of chitotriose, a lysozyme inhibitor, enhanced IL-12 production by J774.1 cells stimulated with heat-killed bacteria. Therefore, enhancement of resistance to lysozyme may be a key factor in the strong IL-12-inducing ability of ML-LYS. These findings have important implications for the design of dairy products that have an immunomodulatory effect using the modified bacteria.     

High-resolution electron microscopy and low-temperature electron diffraction studies of a Bi2212 single crystal grown by the floating zone method

High-resolution electron microscopy of a Bi₂Sr₂CaCu₂O₈ (Bi2212) single crystal prepared by the floating zone method shows that the single crystal is of high quality; there is no intergrowth faulting in the layered structure along thec-axis. Low-temperature selected area diffraction and convergent beam electron diffraction (CBED) studies of this high-quality single crystal show that there is no detectable change for both the point group symmetry of the basic structure and the modulated structure from room temperature to about 15 K. However, a lattice anomaly around 215 K was suggested by measuring the temperature dependence of the ratio between the cross-point distances of the HOLZ lines in high-index CBED patterns. The presence of the lattice anomaly was further confirmed by low-temperature X-ray diffraction.     

Excellent reverse blocking characteristics of high-voltage 4H-SiCSchottky rectifiers with boron-implanted edge termination

Edge-terminated high-voltage Ti/4H-SiC Schottky rectifiers were successfully fabricated by using highly resistive layers at the periphery of Schottky contacts. The highly resistive layers were formed by B⁺ implantation followed by a heat treatment to improve the crystallinity of implanted layers. Utilizing these layers for the edge termination of 4H-SiC Schottky rectifiers, the reverse blocking characteristics were significantly improved in comparison with the rectifiers without edge termination, and a high-blocking voltage over 1100 V (the maximum: 1750 V) was achieved. The temperature dependence of the reverse-blocking characteristics was investigated, and high temperature operation even at 150°C was demonstrated with a blocking voltage over 1100 V     

High-voltage (>1 kV) SiC Schottky barrier diodes with lowon-resistances

Au/6H-SiC Schottky barrier diodes with high blocking voltages were fabricated using layers grown by step-controlled epitaxy. A breakdown voltage of over 1100 V was achieved for silicon carbide (SIC) Schottky barrier diodes. These high-voltage SIC rectifiers had specific on-resistances lower than the theoretical limits of Si rectifiers by more than one order of magnitude. The specific on-resistance increased with temperature according to a T^2.0 dependence. The diodes showed good characteristics at temperatures as high as 400°C     

Penile prostheses for the management of the neuropathic bladder and sexual dysfunction in spinal cord injury patients: long term follow up

During the last 10 years, 90 penile prostheses were implanted in 82 patients with spinal cord injury. Surgery was done 1 month to 25 years (average 4.8 years) after the injury. The follow up period ranged from 1 to 10 years (average 4 years). A prosthesis was implanted for urinary management in 51 patients (62%), for sexual dysfunction in 10 patients (12%) and for both purposes in 21 patients (26%). Ninety-three per cent of the patients who used the implant for urinary management and 64% of the patients who used it for sexual dysfunction were satisfactory. We experienced three extrusions and nine surgical removals due to pain, difficulty of catheterisation and infection (the complication rate was 13.3%). Generally speaking, a penile prosthesis improves the quality of life of patients with spinal cord injury significantly; however, extrusion and infection are still significant problems.     

Mouse germinal center B cells with the xid mutation retain responsiveness to antimouse CD40 antibodies but diminish IL-5 responsiveness

The germinal center (GC) develops in secondary lymphoid tissues in response to thymus-dependent (TD) antigens. To investigate the molecular mechanism of B cell differentiation in GC, we enriched GC B cells from spleen of TD antigen-immunized wild-type and X-linked immunodeficient (XID) mice, and examined the differentiation of GC B cells into antigen-specific IgG1 antibody-forming cells (AFC) in response to anti-CD40 mAb and cytokines. A significant proportion of freshly purified GC B cells expressed receptors for IL-4 and IL-5. Anti-CD40 mAb sustained the viability of GC B cells and IL-4 co-operated with anti-CD40 mAb for further enhancement of the cell viability. Anti-CD40 mAb and IL-4 were essential for inducing differentiation of GC B cells into antigen-specific IgG1-AFC and IL-5 efficiently enhanced their differentiation. GC B cells with the xid mutation responded for proliferation to CD40 ligation to a lesser extent and for the IgG1-AFC response to anti-CD40 mAb together with IL-4, but they showed impaired responsiveness to IL-5, regardless of enhanced expression of IL-5R in response to anti-CD40 mAb and IL-4. These results suggest that anti-CD40 mAb, IL-4 and IL-5 play a critical role in the differentiation of mouse GC B cells. The GC B cells from XID mice show a functional defect with respect to IL-5-mediated differentiation.     

Preoperative evaluation of hepatic functional reserve following hepatectomy by technetium-99m galactosyl human serum albumin liver scintigraphy and computed tomography

It is extremely important to have a good grasp of the acceptable limit of hepatectomy before operation because postoperative liver failure can take a fatal course; however, baseline data on the limit of hepatectomy have not been clearly defined. We therefore evaluated and compared the predicted remnant liver function obtained by computed tomography(CT) and technetium-99m diethylenetriamine penta-acetic acid-galactosyl human serum albumin (99mTc-GSA) liver scintigraphy in order to obtain precise data regarding remnant liver function before hepatectomy. We investigated 20 patients undergoing hepatectomy using the clearance rate of indocyanine green (KICG) as a parameter, and compared the predicted postoperative KICG obtained by CT and by transaxial single-photon emission tomographic (SPET) images acquired by 99mTc GSA liver scintigraphy before hepatectomy. In GSA studies, based on time-activity curves for the heart and liver, we compared HH15 (heart activity at 15 min divided by heart activity at 3 min), LHL15 (liver activity at 15 min divided by heart plus liver activity at 15 min) and KL (obtained from the time-activity curve for the liver) in 103 patients. In 58 patients without increased serum bilirubin, KL was compared with KICG. In four patients, occlusion of the right portal vein was performed with the aim of carrying out secondary hepatectomy, and changes in liver volume were compared between CT and 99mTc GSA liver scintigraphy. The correlation coefficient between the postoperative KICG predicted by CT and the actual postoperative KICG was rather poor, at r = 0.569 (P < 0.05); that between the postoperative KICG predicted by 99mTc GSA liver scintigraphy and the actual postoperative KICG was good, at r = 0.788 (P < 0.01); correlations between KL and HH15 and between KL and LHL15 in 103 patients were very good or good, at r = 0.906 (P < 0.001) and r = 0.807 (P < 0.001), respectively, and that between KL and KICG in 58 patients was very good, at r = 0.916 (P < 0.001). In all four cases of right portal vein occlusion, the remnant liver volume ratio was markedly increased after occlusion in GSA compared with CT, and the postoperative KICG predicted by GSA after occlusion was closer to the actual postoperative KICG than that predicted by CT. It is concluded that 99mTc GSA liver scintigraphy is useful for predicting remnant liver function before hepatectomy and for evaluating changes in regional liver function after occlusion of the portal vein unilaterally.     

Crystal structure of very small particles of chromium and iron

Very small crystals of chromium with diameters less than about 30 Å, formed by vacuum deposition onto a substrate at room temperature, gave rise to an electron diffraction pattern consisting of diffuse haloes. It was concluded that these haloes could not be interpreted in terms of the ordinary b.c.c. structure of chromium but could be interpreted in terms of the new modification of chromium called δ-Cr. This conclusion was drawn by comparing the observed intensity profiles of the diffraction haloes with those calculated from the scattering formula for gas molecules, assuming that the molecules had given numbers of atoms arranged in the δ-Cr structure. Particles of iron also showed similar halo patterns when the particles were very small. The iron and chromium particles all had their normal b.c.c. structures when their sizes exceeded 20 and 100 Å, respectively.