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Milk is used and processed under various environmental temperature, and its physicochemical properties are also strongly affected by temperature. Therefore, it is important to reveal the structure of milk at variable temperatures. In this study, the temperature dependence of the inner structure of bovine casein micelles in the temperature range of 10-40 °C was investigated by in-situ small-angle X-ray scattering (SAXS) method. The micelle size calculated from the SAXS profiles using a micelle model including water domains was almost independent of temperature. The water domain expanded and the distance between the colloidal calcium phosphates (CCP) decreased with increasing temperature. The number of CCPs in a micelle increased, because CCPs were newly formed by the transfer of calcium and inorganic phosphate from serum into the micelle. These structural changes occurred during the cooling process. Therefore, in the temperature range of 10-40 °C, the structure of the casein micelle varied sensitively with the temperature, and these structural changes were thermoreversible in nature.

Thickening agents are commonly used to prevent aspiration, a condition that can prove fatal in the elderly. However, no established indicators exist that show the extent to which sticky food reduces the risk of aspiration. VideoEndoscopy (VE) and VideoFluorography (VF) are the classic inspection methods used for evaluating the function of swallowing, but they are both have limited utility in that they are invasive. In this study, we propose a non-invasive method that exploits esophagus ultrasound videos to estimate the internal flow characteristics of foods, and facilitates quantitative evaluation of the swallowing function. The method combines optical flow with Maximally Stable Extremal Regions (MSER) to extract the movement velocity and position of the esophagus and bolus. The results suggest that movement velocity could be used as an indicator to quantify the internal flow characteristics of foods. The displacement of the esophagus indicates the esophageal opening and could be used as an indicator to evaluate swallowing.

Conversion of liquid milk to cheese curds is the first stage in cheese manufacture. Changing the rigidity of cheese curds through heating and pH control is an established method for preparing fresh curds, whereas a similar method to prepare fully coagulated curds is largely unknown. This study elucidated the effect of temperature variation on the viscoelastic moduli of fully coagulated curds under different pH conditions. The results showed that rennet curds treated at pH 4.8 exhibited drastic changes in the viscoelasticity at 43 degrees C, above which the degree of fluidity exceeded the degree of rigidity. The viscoelastic moduli exhibited exponential decay as a function of temperature, which was independent of pH., Comment: 4 pages, 2 figures, to appear in International Journal of Food Properties

The effect of fat content in cheese curds on their rheological properties was examined using dynamic shear measurements. Surplus fat addition to milk samples caused two distinct types of changes in the temperature dependence of the viscoelastic moduli of resultant curds. The first was a significant reduction in the moduli over a wide temperature range, which is attributed to the presence of liquefied fat globules within the milk protein network. The second was the excess contribution to the low-temperature moduli owing to the reinforcing effect of solidified fat globules. An upward shift in the sol-gel phase transition temperature driven by an increased fat content was also observed., 9 pages, 4 figures

Conditioned culture medium of rat small intestinal epithelial cells suppressed proliferation of spleen lymphocytes stimulated with concanavalin A (approx. 10% of its control [3H]thymidine incorporation) whereas conditioned phosphate-buffered saline of the epithelial cells did not. On the other hand, conditioned saline of the epithelial cells exposed to a mixture of total 22 amino acids at their concentrations in the culture medium suppressed the proliferation (approx. 45% of its control [3H]thymidine incorporation). Neither conditioned saline of the epithelial cells exposed to other medium components nor lysates of freshly harvested epithelial cells suppressed the proliferation. Thus, amino acids synergistically stimulated intestinal epithelial cells to produce substances with the ability to suppress lymphocyte proliferation.

Bovine milk lactoferrin suppressed proliferation of concanavalin A-stimulated rat spleen lymphocytes by absorbing mitogenic lectin activity. Culture media, conditioned by incubating allogeneic intestinal epithelial villus and crypt cells with or without lactoferrin, also suppressed the proliferation. Villus cells absorbed lactoferrin during preparation of conditioned medium and the medium lost a lactoferrin-dependent lymphocyte proliferation-suppressing activity. Although crypt cells did not absorb lactoferrin, its conditioned medium lost the activity. These conditioned media did not alter proliferation of lymphocytes stimulated with 12-O-tetradecanoylphorbol-13-acetate plus ionomycin. Serum proteins, albumin and transferrin, did not substitute for milk lactoferrin. Thus, intestinal epithelial cells modified the reactivity of milk lactoferrin to concanavalin A.

To synthesize nonreducing oligosaccharide derived from trehalose, enzymatic transgalactosylation was investigated using lactose and trehalose as substrates and a commercially available β-ga-lactosidase, which has a tendency to transfer the galactosyl residue to the C4 position of acceptor sugars, from Bacillus circulans. The galactosylation successfully resulted in the efficient production of O-β-D-galactopyranosyl-(1-4)-α, α-trehalose. This trisaccharide showed good stability against acidic treatment.

Pb-free solderable surface finishing is essential to implement Pb-free solder assembly in order to meet with the growing demand of environmental consciousness to eliminate Pb from electronic products. Two types of widely applicable Pb-free surface finishing technologies are developed. One is the multilayer-system including Pd with Ni undercoat. Heat-resistance of Pd enables whole-surface-plating on to leadframe before IC-assembling process. The other is the double-layer-system with low-melting-point-materials, for example, thicker Sn underlayer and thinner Sn-Bi alloy overlayer, dilutes Sn-Bi alloy’s defects of harmful reactivity along with substrate metal and mechanical brittleness with keeping its advantages of solder-wettability and no whisker.

Bovine milk lactoferrin (2 to 20 μg ml−1) changed enhancement of [3H]thymidine incorporation by phytohemagglutinin-stimulated rat spleen lymphocytes into suppression as their lactoferrin-withdrawal incorporation increased to greater than 10 000 cpm culture−1 under the present isotope-labeling conditions. The enhancement disappeared by 15-min delayed addition of lactoferrin after addition of lectin. There was no lactoferrin effect when the cells were stimulated with 12-O-tetradecanoylphorbol-13-acetate plus ionomycin. Thus, lactoferrin has a certain extracellular effect on lymphocyte proliferation in response to the lectin.

高濃度クリームを原料とするバターの製パイ特性を調べた結果,バター物性値(硬さ)との強い相関が判明した.また同バターの微細構造観察結果から,製パイ適性の良好であったバター組織は,微小結晶が多く,それら結晶間に液体脂肪を取り込んでいる構造と推定された.また同製造工程中での圧力付与によりその構造が変化し,形成された結晶塊が組織中に適度に分散しているものと推定された.

pH 4.9～6.0のストリングチーズ(延伸したモザレラチーズ)カードの貯蔵弾性率E',損失弾性率E''を測定した.測定温度の範囲は5～36°C,周波数は1～100Hzである.E'とE''の周波数依存性からマスターカーブを得た.シフトファクターのArrheniusプロットは,直線性を示した.このプロットから活性化エネルギーを算出した. pH 5.5と5.2のチーズカードのE'とE''は他のpHより高い値であった.これらのpH範囲はストリングチーズ製造の最適pH条件と一致した.パラカゼイン粒子間の相互作用は,これらのpH範囲で増加し,繊維状組織をもたらすものと考える.

An electron microscopic observation using anti-human lactoferrin (LF) and gold probe and a reverse hemolytic plaque assay using anti-LF serum were done with the aim of clarifying uptake of LF by B lymphocytes and its release from the cells. The electron microscopic observation clearly demonstrated the occurrence of LF inside of the B lymphocyte. The number of LF-secreting cells, measured by a reverse hemolytic plaque assay, varied with cell types; a human-human hybridoma 9P-13-2 showed the highest number, but the number was much lower with a mouse myeloma. The number of LF-secreting cells increased in proportion to the incubation period with LF. From these results, we concluded that B lymphocytes incorporated LF and then re-secreted it gradually to the extracellular medium.

SUMMARYBovine κ-caseinoglycopeptides (i.e. residues 106–169, CGP) were prepared from κ-casein digested with rennin and a commercial whey protein concentrate. CGP from whey protein concentrate was further divided into seven CGP fractions having different carbohydrate compositions using FPLC. Unfractionated CGP inhibited lipopolysaccharide (LPS)- and phytohaemagglutinin (PHA)-induced proliferative responses of mouse spleen cells and rabbit Peyer's patch cells. The unfractionated CGP also inhibited antibody responses to sheep red blood cells in mouse spleen cell cultures. However, seven CGP fractions having zero to fiveN-acetylneuraminic acid (NANA) residues had different inhibitory effects on both LPS- and PHA-induced proliferative responses of mouse spleen cells. The inhibitory effect on PHA-induced proliferative responses increased with increasing numbers of NANA residues, whereas that on LPS-induced proliferation was highest with the CGP fraction having two NANA residues. Both inhibitory effects decreased significantly after neuraminidase or chymotrypsin digestion. These findings indicate that both the carbohydrate (particularly the NANA residues) and the polypeptide portions are essential for inhibitory effects on LPS- and PHA-induced proliferative responses of mouse spleen cells.

(1993). Inhibition by κ-Casein Glycomacropeptide and Lactoferrin of Influenza Virus Hemagglutination. Bioscience, Biotechnology, and Biochemistry: Vol. 57, No. 7, pp. 1214-1215.

Inhibition from binding of Cholera toxin (CT) to Chinese hamster ovary (CHO)-K1 cells and ganglioside GM1 by lactoferrin (Lf) and kappa-casein glycomacropeptide (GMP) from cow's milk was examined. Both Lf and GMP effectively reduced the CT-derived morphological changes in CHO-K1 cells. The competitive binding assay demonstrated that both Lf and GMP inhibited the binding of CT to GM1, although their affinity for CT was lower than that of GM1. The inhibitory effect of Lf and GMP seemed to be attributed to their terminal sialic acid, although the sugar chain sequence only partially fitted to the CT-receptor.

Our previous studies demonstrated that B lymphocytes incorporated human lactoferrin (LF) and then released it to an extracellular medium. We did competition experiments for better understanding of the interaction between LF and B lymphocytes, using a reverse hemolytic plaque forming assay. Competition between human and bovine LF reduced the number of plaque forming cells (PFC), but human transferrin (TF) showed no inhibitory effect on the PFC counts. These suggested that the receptor on B lymphocytes to human LF did not share with TF but bovine LF. The competition between a synthetic N-terminal nonapeptide of human LF (Gly-Arg-Arg-Arg-Arg-Ser-Val-Gln-Trp) and human LF demonstrated reduced number of PFC dose-dependently. Mild tryptic human LF also reduced the human LFPFC counts, although removal of the C-terminal region did not affect the PFC counts. From these results, we concluded that highly cationic areas of human LF, such as N-terminal, accounted for the interaction with B lymphocytes.

(1992). Large-scale Preparation of κ-Casein Glycomacropeptide from Rennet Casein Whey. Bioscience, Biotechnology, and Biochemistry: Vol. 56, No. 1, pp. 140-141.

In order to determine the characteristics of the glassy-state relaxations of poly(bisphenol-A carbonate) which are closely overlapping each other, shear relaxation modulus was measured from 10 sec to 900 sec at temperatures ranging from ca. -180°C to 0°C. Three relaxations named β, γ and δ in the order of descending temperature were observed separately and master curves were determined by the method of reduced variables. The activation energies of the β, γ and δ relaxations were estimated to be ca. 30, 25 and 9 kcal/mol, respectively. Theoretical considerations suggest that the molecular motions for the β, γ and δ relaxations are the local-mode motion of main chain, the flip motion of a phenylene with a carbonate group, and the rotational motion of a pair of methyl groups belonging to neighboring chains and coupled by van der Waals force.